EPA-460/3-74-027
JULY 1972
STATUS OF INDUSTRY
PROGRESS TOWARDS
ACHIEVEMENT OF THE 1975
FEDERAL EMISSION STANDARDS
FOR LIGHT-DUTY VEHICLES
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Waste Management
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
Ann Arbor, Michigan 48105
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EPA-460/3-74-027
STATUS OF INDUSTRY PROGRESS
TOWARDS ACHIEVEMENT
OF THE 1975 FEDERAL
EMISSION STANDARDS
FOR LIGHT-DUTY VEHICLES
by
W. U. Roessler, T. lura, and J. Meltzer
Aerospace Corporation
El Segundo, California
Contract No. 68-01-0417
EPA Project Officer: F. Peter Hutchins
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Waste Management
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
Ann Arbor, Michigan 48105
July 1972
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This report is issued by the Environmental Protection Agency to report
technical data of interest to a limited number of readers. Copies are
available free of charge to Federal employees. current contractors and
grantees, and nonprofit organizations - as supplies permit - from the
Air Pollution Technical Information Center, Environmental Protection
Agency, Research Triangle Park, North Carolina 27711; or. for a fee,
from the National Technical Information Service, 5285 Port Royal Road,
Springfield, Virginia 22161.
This report was furnished to the Environmental Protection Agency by
Aerospace Corporation, in fulfillment of Contract No. 68-01-0417. The
contents of this report are reproduced herein as received from Aerospace
Corporation. The opinions, findings, and conclusions expressed are
those of the author and not necessarily those of the Environmental Protection
Agency. Mention of company or product names is not to be considered
as an endorsement by the Environmental Protection Agency.
Publication No. EPA-460/3-74-027.
ii
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FOREWORD
This report, prepared by The Aerospace Corporation for the Environmental
Protection Agency, Division of Emission Control Technology, presents a
compilation and assessment of all available information pertaining to the
technological progress made by the automotive industry toward meeting the
1975 Federal emission standards for light-duty vehicles.
The status of the technology reported here is that existing at the time of the
EPA Suspension Request Hearings held in Washington, D. C. , between April
10 - 28, 1972. Important findings and conclusions are presented in the
Highlights and Executive Summary sections of the report. Material related
to candidate 1975 emission control systems is given in Section 2. An assess-
ment of emission control techniques and system components (engine modifi-
cations, EGR, oxidation catalysts, thermal reactors, and secondary air
supply) is presented in Sections 3 through 7. Engineering emission goals
and emission control system deterioration characteristics with mileage
accumulation are discussed in Section 8. The interim standards proposed
by the automobile manufacturers are summarized in Section 9 and mainte-
nance, cost, safety and production lead time aspects are briefly discussed
in Sections 10 and 11. Section 12 presents a brief status report of uncon-
ventional automotive engines, including the rotary (Wankel), diesel, gas
turbine, stratified charge, Rankine cycle, and Stirling cycle. Finally, the
highlights of the_ statements made at the EPA Suspension Request Hearings
of April 10 - 28, 1972 by witnesses who are not a part of the automotive
industry are presented in Appendix A.
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ACKNOWLEDGMENT
Appreciation is acknowledged for the guidance and continued assistance
provided by Mr. F. P. Hutchins of the Environmental Protection Agency,
Division of Emission Control Technology, who served as EPA Project Officer
for this study.
The following technical personnel of The Aerospace Corporation made
valuable contributions to the assessment performed under this contract.
J. A. Drake
L. Forrest
M. G. Hinton
D. E. Lapedes
P. P. Leo
W. M. Smalley
C. Speisman
K. B. Swan
U, U,
W. U. Roessler, Manager
Technology Assessment Study
Approved by:
Toru lura, Director
Pollution and Resources Programs
s'eph Meltzer, Gr
vironmental Pr
Director
ams Directorate
IV
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CONTENTS
FOREWORD iii
ACKNOWLEDGMENT iv
HIGHLIGHTS xv
EXECUTIVE SUMMARY 1
1. Introduction 1
2. Candidate 1975 Emission Control Systems 1
3. Unconventional Automotive Engines 8
4. Engine Modifications 9
5. Exhaust Gas Recirculation 10
6. Oxidation Catalysts 10
7. Thermal Reactors 22
8. Secondary Air Supply 23
9. Emission Goals 23
10. Interim Standards 29
11. Production Lead Time 34
12. Maintenance, Safety, and Cost 36
13. Regulatory Problem Areas 37
1. INTRODUCTION .* 1-1
2. CANDIDATE 1975 EMISSION CONTROL SYSTEMS 2-1
2. 1 Summary Discussion 2-1
2.2 Selected Systems--By Manufacturer : 2-8
2. 2. 1 American Motors 2-8
2.2.2 Chrysler 2-18
2. 2.3 Ford 2-31
2.2.4 General Motors 2-51
2.2.5 International Harvester 2-67
2. 2. 6 Alfa Romeo 2-75
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CONTENTS (Continued)
2.2.7 BMW 2-75
2.2.8 British Leyland Motor Corporation 2-75
2.2.9 Citroen 2-81
2.2. 10 Daimler-Benz AG (Mercedes-Benz) 2-81
2.2. 11 Honda Motor Company 2-91
2.2. 12 Mitsubishi Motors Corporation .2-93
2.2. 13 Nissan (Datsun) 2-95
2.2. 14 Renault 2-102
2.2. 15 Rolls-Royce Motors Limited 2-104
2.2. 16 Saab . 2-107
2.2. 17 Toyo Kogyo 2-115
2. 2. 18 Toyota . . 2-120
2.2.19 Volkswagen 2-125
2.2.20 Volvo 2-130
REFERENCES 2-141
3. ENGINE MODIFICATIONS 3-1
3. 1 Background 3-1
3.2 Modification Requirements for 1975 3-2
3.3 Carburetion System Modifications 3-4
3.3.1 General 3-4
3.3.2 Industry Status 3-5
3.4 Ignition System Modifications 3-8
3.4.1 General . .. 3-8
3.4.2 Industry Status 3-9
REFERENCES 3-13
VI
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CONTENTS (Continued)
4. EXHAUST GAS RECIRCULATION
4. 1 Background
4. 2 Requirements for 1975
4. 3 Industry Status
REFERENCES
5. OXIDATION CATALYSTS
5. 1 Summary Discussion
5. 2 Catalyst Types
5.2. 1 Typical Catalysts
5.2.2 Automotive Catalyst/Substrate
Combinations
5. 3 Specific Catalyst Features (By Company)
5. 3. 1 Air Products and Chemicals, Inc. -
(Houdry Division)
5. 3. 2 American Cyanamid
5. 3. 3 Chemico
5. 3.4 Engelhard Industries
5. 3. 5 W. R. Grace and Co
5. 3. 6 Matthey Bishop, Inc
5. 3. 7 Monsanto
5.3.8 Oxy-Catalyst, Inc
5.3.9 Union Carbide Corporation . .
5.3. 10 Universal Oil Products Company
5. 3. 11 Miscellaneous
5.4 Substrate and Converter Design Features
5.4. 1 Substrate Features (By Company)
4-1
... 4-1
, . . . 4-2
4-3
4-5
5-1
... 5-1
5-10
5-11
5-12
5-13
5-13
5-15
5-15
5-15
5-16
5-16
5-17
5-17
5-17
5-18
5-18
5-18
5-18
5.4.2 Converter Design Features (By Company) . . . 5-28
Vll
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CONTENTS (Continued)
5.5 Contamination and Deterioration Effects 5-36
5. 5. 1 Contamination Effects . . . 5-36
5.5.2 Deterioration Effects 5-45
5.6 Principal Problem Areas and Plans for Resolution . . . 5-49
5. 6. 1 Contamination Control 5-50
5. 6.2 Increased Catalyst Activity 5-50
5. 6. 3 Thermal Control 5-56
5. 6.4 Attrition Control 5-56
5.7 Emissions 5-59
5.7. 1 Air Products and Chemicals (Houdry)
Division) 5-60
5.7.2 American Cyanamid 5-67
5.7.3 Chemico 5-67
5.7.4 Engelhard 5-70
5.7.5 W.R. Grace 5-82
5.7. 6 Johnson-Matthey . 5-97
5.7.7 Monsanto 5-104
5.7.8 Oxy-Catalyst 5-104
5.7.9 Union Carbide 5-108
5.7. 10 Universal Oil Products 5-108
5.7. 11 Kali-Chemie 5-115
5.7. 12 Degussa . . . 5-115
5.8 Overtemperature Protection Systems 5-120
5.9 Projected Maintenance and Replacement
Procedures 5-126
REFERENCES 5-129
6. THERMAL REACTORS 6-1
6. 1* Summary Discussion 6-1
6.2 Special Design Features 6-3
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CONTENTS (Continued)
6.2. 1 American Motors
6. 2. 2 Chrysler
6.2.3 Ford
6.2.4 General Motors
6.2. 5 International Harvester
6. 2. 6 British Leyland
6.2.7 Daimler-Benz
6. 2. 8 Nissan
6. 2. 9 Saab
6. 2. 10 Toyo Kogyo
6. 2. 11 Toyota
6.2. 12 Volkswagen
6. 2. 13 Volvo
6. 2. 14 DuPont
6.2. 15 Esso
6. 2. 1 6 Ethyl
REFERENCES
7. SECONDARY AIR SUPPLY
7. 1 Summary Discussion
7.2 Selected Systems (By Manufacturer)
REFERENCES
8. EMISSION GOALS
8. 1 General
8.2 Deterioration Factor
8. 3 Prototype -to-P reduction Slippage Factor
8.4 Production Quality Control Factor
8. 5 Selected Prototype Emission Goals
.... 6-3
.... 6-4
.... 6-4
.... 6-5
.... 6-6
.... 6-7
.... 6-7
.... 6-7
.... 6-8
.... 6-10
.... 6- 11
.... 6-11
.... 6-12
.... 6-12
.... 6-14
.... 6-15
.... 6-18
.... 7-1
.... 7-1
.... 7-2
.... 7-4
.... 8-1
. . . . 8-1
.... 8-4
.... 8-5
. . . . 8-5
. . . . 8-8
IX
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CONTENTS (Continued)
8. 5. 1 American Motors -.-.-.
8. 5. 2 Chrysler
8. 5. 3 Ford Motor Company
8. 5.4 General Motors
8. 5. 5 International Harvester
8. 5. 6 British Leyland
8. 5. 7 Daimler-Benz
8. 5. 8 Mitsubishi . . .
8. 5. 9 Nissan
8. 5. 10 Saab
8. 5. 11 Toyo Kogyo
8. 5. 12 Toyota
8. 5. 13 Volkswagen
8. 5. 14 Volvo
8. 5. 15 Catalyst Manufacturers
REFERENCES
9. INTERIM STANDARDS
9. 1 Summary Discussions
9.2 Proposed Interim Standards
9.2. 1 American Motors
9.2.2 Chrysler
9.2.3 Ford Motor Company
9.2.4 General Motors
9.2.5 International Harvester
. 9. 2. 6 British Layland
9.2.7 Daimler-Benz
9.2.8 Mitsubishi
9. 2. 9 Nissan
8-8
8-12
8-13
8-21
8-26
8-27
8-29
8-29
8-30
8-31
8-33
8-34
8-34
8-35
8-36
8-39
9-1
9-1
9-4
9-4
9-8
9-9
9-12
9-12
9-13
9-14
9-14
9-15
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CONTENTS (Continued)
9.2. 10 Saab-Scania 9-15
9.2. 11 Toyo-Kogyo 9-16
9.2. 12 Toyota 9-16
9.2. 13 Volkswagen 9-17
9.2.14 Volvo . .. 9-17
9.2. 15 Chemico 9-17
9.2.16 Engelhard 9-17
9.2. 17 W. R. Grace 9-18
9.2. 18 Universal Oil Products 9-18
REFERENCES 9-19
10. MAINTENANCE, SAFETY, AND COST 10-1
10. 1 Maintenance 10-1
10. 2 Safety 10-3
10. 2. 1 General 10-3
10. 2. 2 Poor Passing Performance 10-3
10.2.3 Fire Hazard 10-3
10.2.4 Catastrophic Component Failures 10-5
10. 3 Costs 10-5
10. 3. 1 General 10-5
10. 3. 2 Increased Purchase Price 10-6
10.3.3 Maintenance Costs 10-7
10.3.4 Fuel Costs 10-8
REFERENCES 10-9
11. PRODUCTION LEAD TIME 11-1
11.1 Introduction 11-1
11. 1.1 Data Source 11-1
11. 1.2 Terminology 11-1
11. 1.3 Schedule Considerations 11-1
XI
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CONTENTS (Continued)
11.2 Pacing Items ..,; 11-2
11. 2. 1 American Motors 11-3
11.2.2 Chrysler 11-3
11. 2.3 Ford 11-4
11.2.4 General Motors 11-4
11.3 Automobile Manufacturers' Schedules for
Catalytic Converters 11-4
11.4 Catalyst Suppliers' Schedules 11-5
11.5 Contractual Commitments with Suppliers 11-8
11.6 Schedule Integration 11-8
11.7 Schedule Compression and Cost Interactions 11-10
REFERENCES 11-13
12. UNCONVENTIONAL AUTOMOTIVE ENGINES 12-1
12. 1 Wankel (Rotary) Engine ....'. 12-1
12. 1. 1 Ford 12-1
12. 1. 2 General Motors 12-2
12. 1.3 Daimler-Benz 12-3
12. 1.4 Toyo Kogyo . 12-3
12. 2 Diesel Engine 12-4
12. 3 Gas Turbine 12-5
12. 3. 1 General 12-5
12.4 Stratified Charge Engine 12-6
12.4. 1 General . . 12-6
12.4.2 Ford 12-7
12. 4. 3 General Motors 12-7
12.4.4 Chrysler 12-8
12. 5k Rankine Engine 12-8
12. 5. 1 Ford 12-8
XII
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CONTENTS (Continued)
12. 5. 2 General Motors 12-9
12. 5. 3 Chrysler 12-9
12. 6 Stirling Engine 12-9
12. 6. 1 Ford 12-9
12. 6. 2 General Motors 12-10
REFERENCES 12-11
APPENDIX: NONAUTOMOTIVE INDUSTRY TESTIMONY A-1
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HIGHLIGHTS
A review and evaluation was made of all available information pertinent to
the technological progress of the automotive industry in meeting the 1975
Federal emission standards for light duty vehicles. Assessment of the
status of the industry as of the time of the EPA Suspension Request Hearings
(April 10-28, 1972) resulted .in the following findings.
1. All but a small fraction of the 1975 model year light duty vehicle
production will utilise spark ignition reciprocating engines. The
typical 1975 first-choice emission control system is based on the
use of an oxidizing catalytic converter. Additional features of the
system include exhaust gas recirculation, improved carburetion
and ignition, and devices or techniques to promote fast warmup of
the induction system and catalytic converter.
2. In addition to spark ignition reciprocating engine systems, Toyo
Kpgyo will produce rotary engine vehicles and Daimler-Benz will
produce diesel engine vehicles for the 1975 U.S. market. The
Toyo Kogyo rotary engine emission control system consists only
of the addition of a thermal reactor. The Daimler-Benz diesel
vehicle (220D) is stated to be capable of meeting 1975 standards
without aftertreatment devices.
3. The Toyo Kogyo rotary engine emission control system has suc-
cessfully achieved the company's 1975 low mileage emission goals.
Toyo Kogyo expressed optimism that its system would be able to
meet the 1975 standards. However, this type of engine cannot be
produced in sufficient quantities by the automotive industry to
satisfv any significant fraction of the 1975 production requirements.
4. Daimler-Benz believes that a vehicle with a pre-chamber diesel
engine of the 2. 2-liter class can meet the 1975 standards without
the use of aftertreatment devices. It is unlikely that this type of
xv
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engine can meet the 1976 NO standards. The current low production
.X
rate of this engine cannot be increased substantially by 1975.
5. Although the emission potentials of the stratified charge, the gas
turbine, the Rankine, and the Stirling "engines look promising and
although substantial progress on them has been made in recent years,
they are still in the development stage and a number of technical
problem areas have yet to be resolved, including the development of
mass production techniques. Therefore, mass production of these
engines cannot be scheduled, at this time.
6. No manufacturer has yet demonstrated meeting the 1975 standards at
50, 000 miles. Many automobile and catalyst manufacturers have met
the 1975 standards at low mileage.
7. Only a limited number of test vehicles have been driven in extended
durability tests beyond 20, 000 miles. Johnson-Matthey has tested
a car equipped with a noble metal monolithic catalyst which had
emission levels below the 1975 standards through the 24, 000-mile test
duration to date. However, lead-sterile fuel was used. American
Motors, Chrysler, General Motors, and Volvo have longer mileage
accumulations ranging from 25, 000 to 50, 000 miles. Although these
tests were encouraging in that emission levels were below the stan-
dards at discrete mileage points, they must be viewed with caution
since in all cases there were some factors present which preclude
direct comparison of the emission data with the 1975 standards.
These include high emissions at intermediate mileage points, non-
standard driving cycles, obsolete test procedures, and/or use of fuel,
with a lead content below that anticipated for 1975.
8. The available emission data may reflect conservative emission levels
becaus , in most cases, the vehicles tested did not include all of the
emission control system components or improvements projected for
the 1975 systems. Current fleet tests, which in many cases include
prototypes of the proposed system components, should give an
xvi
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indication of the degree of emission reduction attributable to these
components.
9. Improved catalysts are being developed and tested by the catalyst
industry and have shown better emission performance and durability
characteristics. However, they have not yet been tested in con-
junction with the proposed 1975 vehicle/emission control system
configurations. Only after durability testing in 1975 prototype
vehicles can a quantitative assessment be made of the emission con-
trol potential of these improved catalysts.
10. The manufacturers' low mileage emission goals for 1975 prototype
emission control systems are substantially lower than the 1975 stan-
dards to allow for prototype-to-production design and performance
variations and to allow for anticipated deterioration in emission
control with mileage accumulation. With the exception of the Toyo
Kogyo rotary engine these low mileage goals have not been met.
11. Test data from some vehicles equipped with catalytic converters
indicate rapid emission degradation during the low mileage (0-4, 000
miles) period followed by either gradual or no deterioration as mileage
is accumulated. Other catalytic converter vehicle tests do not show
the initial rapid deterioration and exhibit a gradual emission deterior-
ation with mileage accumulation. Therefore, deterioration factors
determined from one type of vehicle/emission control system are not
necessarily applicable to other configurations. Available emission
data suggest that emission degradation is more severe for systems
with initially low emissions.
12. All manufacturers have requested adoption of interim standards less
stringent than the 1975 standards. The proposed interim standards
ran^? from values equal to the 1974 standards to approximately 40
percent of these values. Even this 40 percent value is still sub-
stantially higher than the 1975 standards. Most automobile manu-
facturers have proposed interim standards that can be met by means
xvii
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of engine modifications. Only Ford and International Harvester
selected interim standards which require the use of a catalytic
converter.
13. The catalytic converter is the most critical component in 1975 emis-
sion control systems because of the 50, 000-mile durability require-
ment. Oxidation catalysts have inherent performance degradation
and physical durability problems which to date have not been com-
pletely resolved. Loss of catalytic activity is caused by contamina-
tion from fuel and oil additives, such as lead, phosphorous, sulfur,
barium, and zinc, and by loss of catalytic surface area caused by
exposure to excessive temperature. The physical durability prob-
lems relate to thermal stresses, vibrational loads, and over-
temperature conditions which have caused mechanical failure of the
catalyst substrate and/or its conuuner.
14. Although catalyst development is proceeding on both noble and base
metal catalysts using monolithic or pellet substrates, most manu-
facturers are concentrating their efforts on noble metal/monolithic
catalytic converters. To date the lowest emission data at high
mileage were reported for a vehicle incorporating a noble metal/
monolithic catalyst.
15. Although quantitative relationships between lead content and emissions
have not yet been established it is the opinion of some automobile and
catalyst manufacturers that catalyst performance is strongly affected
by the lead content in fuel, even at lead levels below 0. 07 gm/gal.
If this effect is confirmed a maximum lead level should be established
which takes into consideration both catalyst performance as well as fuel
refinery and handling aspects at low lead levels.
16. With the - cception of Toyo Kogyo, thermal reactor-only systems are
not being considered by the automobile manufacturers as first-choice
systems. Although the thermal reactor has low emission degradation
and is relatively insensitive to fuel contamination, most automobile
XVlll
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manufacturers have reported such negative aspects as poor mechanical
durability, high underhood temperatures, and low fuel economy,, In
addition, 1976 NO standards cannot be met with the thermal reactor
3C
alone.
17. The catalytic converter is the pacing production development item that
impacts on the production lead time requirement for the mass pro-
duction of 1975 emission control systems. Based on information from
both the automobile manufacturers and catalyst suppliers, the overall
lead time for catalytic converter production ranges from 24 to 28
months (this requires a firm commitment in mid-1972). Some catalyst
suppliers have estimated that further schedule compressions can be
made, but with corresponding increases in unit costs. Sufficient
information was not available to allow a critical evaluation of schedule
compression possibilities and effects.
18. Several important issues which have a great effect on whether the
automobile manufacturers can meet the 1975 standards are still un-
resolved. These include emission averaging for certification and
assembly line vehicles, maximum allowable fuel contaminant levels,
clarification of maintenance procedures for all emission control
system components, and definition of warranty and recall procedures.
All these issues must be resolved before a quantitative evaluation of
the manufacturers' ability to comply can be made.
19. A number of automobile manufacturers have expressed the opinion that
the applicability of the EPA certification driving cycle to vehicles
incorporating a catalytic converter and/or thermal reactor should be
re-examined. The cycle may be too mild to adequately test the
emission performance and safety aspects of these systems.
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EXECUTIVE SUMMARY
1. INTRODUCTION
This report presents a compilation and assessment of all available information
pertaining to the technological progress made by the automotive industry
toward meeting the 1975 Federal emission standards for light duty vehicles
(HC = 0. 41 gm/mi, CO = 3.40 gm/mi, NOX = 3. 10 gm/mi).
The status of technology reported here is that existing at the time of the EPA
Suspension Request Hearings held in the period of April 10-28, 1972. Infor-
mation was taken from material in the manufacturers' applications for sus-
pension of the 1975 emission standards, testimony presented at the hearings,
and supplementary material provided by the hearing witnesses at the request
of the hearing panel. To supplement this information in certain areas, data
were used from previous responses by industry to EPA requests for
technology information.
Topics covered in this report include first-choice emission control systems,
possible alternate systems, unconventional engine designs, and emission con-
trol system components. Emphasis has been directed toward low and high
mileage emissions, component and system durability characteristics (in par-
ticular, catalytic converters), and factors affecting emission goals and
interim standards.
This section of the report summarizes the more pertinent information from
this assessment. Further details can be found in the main body of the report.
2. CANDIDATE 1975 EMISSION CONTROL SYSTEMS
The emission control systems projected for 1975 model vehicles are exempli-
fied by the following package of components and engine modifications:
Oxidizing catalytic converter
Air injection
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Exhaust gas recirculation (EGR)
Carburetor modifications
Ignition system modifications
t -
With the exception of Toyo Kogyo, which utilizes a thermal reactor on their
rotary engine, all of the manufacturers' first-choice systems incorporate an
oxidizing catalytic converter with air injection to promote the oxidation of
unburned hydrocarbons (HC) and carbon monoxide (CO) of the engine exhaust.
The catalytic converter type which appears most frequently among the
selected first-choice systems is the noble metal/monolithic catalyst exempli-
fied by the Engelhard PTX design. General Motors, International Harvester,
and a number of other manufacturers have selected the base metal/pelletized
type of converter as a first-choice design. In many cases, a firm decision
as to catalyst type has not been made and several systems are being tested
i
and evaluated concurrently.
Nearly all of the first-choice systems employ EGR for the control of oxides
of nitrogen (NO ). However, most British Leyland and the Toyo Kogyo and
Saab vehicles exported to the United States are reported to be capable of
meeting the 1975 3.10 gm/mi NOX standard without EGR.
In addition to the aftertreatment systems delineated above, a number of
manufacturers, including Chrysler, General Motors, and Ford, utilize a
partial thermal reactor in place of the conventional exhaust manifold, pri-
marily to provide rapid warmup of the catalytic converter under cold start
conditions.
Carburetion system modifications that have been identified for first-choice
systems range from complete redesigns, utilizing new concepts, to minor
improvements to the current conventional systems. These modifications are
generally directed toward improving the precision and stability of the air/fuel
ratio and also v :lude such features as altitude compensation, quick release
choke devices, and induction manifold heating. All of the domestic and sev-
eral of the foreign manufacturers propose, or have in development, electronic
(breakerless) ignition systems which are targeted for inclusion in their
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first-choice system. These systems generally provide an improvement in
spark-timing precision, consistency, and reliability.
The most pervasive problem in the industry relative to 1975 emission control
systems appears to be the lack of adequate durability in the catalytic conver-
ters currently under test. Catalyst durability is composed of two aspects:
physical durability and emission durability. For monolithic designs, the
physical aspect of the problem is symptomized by cracking and local melting
of the catalyst substrate, due to vibratory loads and overtemperature. For
pellet-type systems, the problem is exhibited as a loss of catalyst material
caused by brittleness of the pellets and/or deficiencies in the design and con-
struction of the support grids. Physical breakdown appears to be particularly
severe in 4-cylinder engine systems because of characteristically high vibra-
tions. Canister deformation and rupture failures have occurred with both
types of converter designs.
The emission durability is most strongly impacted by a loss of catalyst
efficiency with accumulated mileage without mechanical deterioration. The
problem has several causes, including poisoning of the catalyst due to small
quantities of lead, sulfur, or phosphorus in the fuel and/or loss of catalyst
surface area due to overheating. The overheating effect appears to be pri-
marily related to rich air/fuel operation and may be encountered under
various engine/vehicle operating conditions including acceleration, decelera-
tion, choking, high power operation, and malfunctions of different types.
In addition to the catalytic converter, durability problems with other 1975
emission system components are reported. Notable among these are EGR
valves and thermal reactors.
Other problems which appear to be characteristic of the 1975 emission
control systems are degradation of vehicle driveability, loss of vehicle per-
formance, and deterioration of fuel economy. Driveability problems reported
encompass the following: loss of cold start drive-away capability, stumbles,
stalls, inadequate acceleration, difficulty in hot starting, rough idle, surging,
-------
hesitation, and backfire. Power losses and losses in fuel economy (relative
to 1972 vehicles) range from 10 to 20 percent for both parameters.
With regard to the degradation of vehicle driveability, performance, and fuel
economy, improvements are being sought by modifying the design of the fuel
metering, induction, and ignition systems. Electronic engine control, which
integrates the adjustment of ignition timing, air/fuel ratio, and EGR flow rate
with respect to engine load and RPM, may provide the means to achieve an
optimized balance between exhaust emissions versus vehicle performance
and economy. Electronic engine control is a feature of the Chrysler first-
choice system.
The emission performance .of the 1975 systems is categorized in terms of
low and high (4000 ) mileage accumulation. Many of the manufacturers' low
mileage test results fall well within the 1975 standards; most of these systems
drift outside the limits of the standards at low levels of mileage accumulation.
In general, zero mileage vehicles do not meet the manufacturers' engineering
emission goals.
The status of high mileage emission level capabilities for 1975 first-choice
systems may be gauged from the summary of best high mileage emission
results presented in Table!. The emissions obtained at 32,000 miles from
an American Motors Javelin (3000-lb, 6-cylinder, 258-CID engine) equipped
with an AC-Delco base metal, pelletized catalytic converter (Car D17-11)
were below the standards. However, the HC emission level at 32, 000 miles
is above the standard when determined on the basis of a straight-line, least-
squares fit of all data points. This system is continuing to accumulate
mileage (EPA durability driving schedule).
Two other high mileage vehicles may be noted. One of these is an American
Motors 1970 production model Hornet (same vehicle weight "and engine as the
Javelin). Th 3 vehicle (Car DOO-24), equipped with an Engelhard PTX 423
noble metal monolithic catalytic converter, has completed 50, 000 miles of
durability testing and at this mileage a least-squares data fit indicates
-------
Table 1. First-Choice Systems, Summary of Best High Mileage Emission Results
Manufacturer
American Motors
American Motors
Chrysler
Ford
General Motors
International Harvester
Alfa Romeo
BMW
British Leyland
Citroen
Daimler-Benz
Honda
Mitsubishi
Nissan
Renault
Saab
Toyo Kogyo
Toyota
Volkswagen
Volvo
Test or Car No.
D17-11
DOO-24
698
Ford tfl
2222
Austin
R16
75-A
OB44085
First-Choice System Components
EM + EGR + AI + OC
EM + EGR + Al + OC
EM + EGR + AI + PTR + OC
EM + EGR + AI (+ TR) f OC
EM + EGR + AI + PTR + OC
EM + EGR + AI + OC
Not defined
EM + EGR + AI + OC
EM + AI + OC
Not defined
EM + EGR + AI + OC
Not defined
EM + AI (+ TR) + OC
EM + EGR + AI + OC
AI + OC
EM + AI + OC
(EM) + AI + TR
(+ OC for reciprocating)
EM + EGR + AI + OC
EM(+ EFI) + EGR + Alt TR + OC
EM + EGR + AI + OC
Mileage
32,000
50, 000
43, 000
8, 000
8,000
4,000
11,400
10,000
8,000
16, 000
8,000
25,3448
1975 CVS-CH
Emissions, gm/mi
HC
0. 39
(0. 32
(0. 16
0.25
0.32
0. 33
0.28
0.5
0.2
0. 32
0.27
0. 24
CO
3.04
4. 8
1.88
1.84
4.6
4. 7
2.73
3.9.
1.2
3.91
2.82
2.45
NO
1. 5
2. I)1
3.91)2
2.55
2.6
2.32
0. 78
1.69
1.29
1.82
Remarks
9, 12, Base OC
Noble OC
5, b, 12, NobleOC
9, 13, Noble OC
9, Base OC
3
6
6
7, Noble OC
6
6
6
3
14, Noble OC
4, 10, Noble OC
6, Noble OC
5,11, 14,NobleOC
6, Noble OC
5, 12, Noble OC
1. Least-squares fit to 1972 test results converted to 1975 test procedure; slow choke
2. 1972 CVS-C test procedure
3. No high mileage data met standards
4. Emissions package incomplete/uncertain
5. Converter subsequently failed (within 4000 miles)
6. No high mileage data provided
7. Exceeded standards below 17,000 miles
8. Converter miles
9. Test continuing
10. Average of two tests
11, After maintenance
12. Standards were exceeded at lower mileage points
13. Best of two tests
14. Non-standard maintenance schedule
AI Air Injection
EFI Electronic Fuel Injection
EGR - Exhaust Gas Recirculation
EM Engine Modifications
OC - Oxidizing Catalyst
PTR - Partial Thermal Reactor
TR - Thermal Reactor
-------
the emissions were 0. 32, 4. 8, and 2. 1 gm/mi for HC, CO, and NOX>
respectively. The 1975 CO standard of 3.4 gm/mi was exceeded at roughly
30, 000 miles. The other high mileage vehicle which is noteworthy is a
400-CID Chrysler car. This vehicle (Car 698), equipped with dual Engelhard
platinum/monolith converters which had been transferred from another vehi-
cle, developed a total converter mileage of 43,000 miles at emission levels
of 0.16, 1.88, and 3.91 gm/mi for HC, CO, and NOX, respectively. The
catalyst container failed mechanically at this point.
In addition to the two high mileage vehicles discussed above, the Volvo first-
choice emission vehicle might also be mentioned. This system accumulated
25,344 converter miles within standards. The catalyst failed mechanically^
at 29, 900 miles.
Though not included in Table 1, because no high mileage emission data were
provided, the Toyo Kogyo rotary engine with thermal reactor deserves special
mention. Toyo Kogyo states that this system has met its internal engineering
goals and is confident that it will achieve the 50, 000-mile emissions durability
requirement.
Summarizing the emissions performance indicated by the data in Table 1,
eight first-choice systems have met the standards at accumulated mileages
in excess of 4000 miles. None of these has achieved the 50,000-mile dura-
bility requirement; one system has met the standards at 32, 000 miles and is
still under test. A total of three systems have demonstrated the potential of
achieving 25,000 converter miles within standards; two of the converters
subsequently failed in test. A total of three catalytic converter failures
occurred among the eight test vehicles which met the standards at more than
4000 miles.
In the main, the alternate systems under investigation by the manufacturers
for potential u_e in 1975 model year vehicles incorporate different types or
designs of catalytic converters but are otherwise similar to the emission con-
trol packages selected as first-choice systems. A typical example is General
Motors, whose second- and third-choice systems substitute noble metal pellet
-------
and noble metal monolithic converter designs for the first-choice base metal
pellet converter design. Therefore, the discussion in the preceding para-
graphs, encompassing system descriptions, problems and plans for resolu-
tion, and fuel consumption and performance penalties, applies also to most
of the systems in the alternate systems category.
At least four manufacturers are experimenting with alternate 1975 emission
control systems which incorporate full-size thermal reactors. These
J*
are Ford, General Motors, International Harvester, and Nissan. The Ford
system is installed on their Group II test fleet vehicles which are equipped
with dual (series) noble metal catalytic converters, a thermal reactor, and
EGR. The General Motors system consists of a thermal reactor with EGR.
Durability data for these systems were not provided. The International Har-
vester system exceeds the standards at zero mileage.
The Nissan system comprises engine modifications, a thermal reactor, EGR,
and an oxidizing catalytic converter. Problems encountered with the Nissan
reactor may be represented as being typical of thermal reactors. These prob-
lems are reactor core deformation and durability, and the need to develop
inexpensive materials which will survive the high temperature, turbulent core
environment. The fuel consumption penalty for the Nissan system was quoted
as 10 to 15 percent relative to 1972 model year vehicles. The maximum mile-
age accumulated on this system was 32, 000 miles at emission levels ranging
from 0. 5 to 0.75 gm/mi HC, 11 to 13 gm/mi CO, and 0.75 to 1.1 gm/mi NO .
.X
This system may be under development for 1976.
It may be noted that Toyota is testing a thermal reactor system which also
appears to be targeted to the 1976 model year. This system incorporates
engine modifications, EGR, an oxidizing catalyst, and a reducing catalyst.
Two vehicles equipped with this system failed the CO standard before 8000
miles were accumulated.
The Toyo Kogyo thermal reactors are classified as first-choice devices.
-------
3. UNCONVENTIONAL AUTOMOTIVE ENGINES
Automotive engine candidates classified here as unconventional include the
Wankel, the stratified charge; the diesel, the gas turbine, and the Rankine
and Stirling engine systems. The continuous combustion engine types (gas
turbine, Rankine, Stirling) generally show encouraging emission results. .
However, the Rankine system is regarded by the automobile manufacturers as
being too complex and costly for widespread automotive application and all
three of these engine types are considered to be unavailable in sizeable pro-
duction quantities before the 1980"*" time period. The light duty diesel engine,
on the basis of anticipated test procedures and current test results, can meet
the 1975 standards without exhaust treatment devices; however, the 1976
NO requirement appears to be unattainable by the diesel even when incorpo-
rating the techniques (e.g., EGR, NO catalyst) presently under consideration
for internal combustion gasoline engines.
The Wankel rotary engine is being produced by Toyo Kogyo at a low production
rate of about 15,000 per month for the Mazda vehicle and is also under study
and development by Ford, General Motors, and Daimler-Benz. The untreated
exhaust contains somewhat more HC, approximately the same CO, and consid-
erably less NOX than the conventional reciprocating engine. In general, the
domestic manufacturers visualize the possible advantages of the Wankel to be
primarily in the areas of reduced size and weight, which could permit the util-
ization of some emission control systems not suited to the conventional engine
(e.g., large thermal reactor). Toyo Kogyo is confident that its rotary engine
system equipped with a thermal reactor will demonstrate the capability of
meeting the 50,000-mile emissions durability requirement. Nevertheless, the
prospects of developing this engine for high-volume industry-wide production
output in time for the 1975 or 1976 model year seem remote.
Another system offering the potential of low emissions is the stratified charge
engine which achieves satisfactory (no misfire) operation at high EGR rates
«
by providing a localized rich charge in the vicinity of the spark electrodes.
This engine type, which incorporates a thermal reactor, EGR, and
-------
oxidizing catalyst, may permit the achievement of very low NO emissions
without a NOX catalyst and with relatively good fuel economy. The develop-
ment of the stratified charge engine is being pursued by Ford, Texaco, and
Chrysler. A variation of this principle, embodying a prechamber device, is
being studied by General Motors. These systems are still under development
and are not expected to be available in production quantities for a number of
years.
Ford, General Motors, and Chrysler have passenger car gas turbine pro-
grams. Chrysler states that its engine would meet the 1975 emission
standards. However, the 1976 standards have not yet been demonstrated.
Major problem areas include poor fuel economy at part load and poor accel-
eration characteristics. All manufacturers indicate that sizable production
is not possible until the 1980 time period.
4. ENGINE MODIFICATIONS
Certain components of the 1975 emission control system, such as EGR and the
catalytic converter, impose demanding requirements on the design of the car-
buretion and ignition systems with respect to response, precision, flexibility,
and control characteristics. Accordingly, all of the major automobile manu-
facturers are actively pursuing the development of new or improved carbure-
tion, ignition, and control devices for the projected 1975 emission systems.
The principal carburetion system modifications include altitude and ambient
temperature compensation, and electrically heated chokes. At least three
domestic manufacturers, Chrysler, Ford, and General Motors, are conduct-
ing in-house development work on electronically controlled fuel injection sys-
tems. A number of the foreign manufacturers already have'these types of
systems in production. With regard to ignition system modifications, the
general industry trend appears to be toward the adaptation of electronic sys-
tems typified by Chrysler's breakerless, inductive design in which ignition
coil currejit is switched by an electronic control unit in response to timing
signals produced by a distributor magnetic pickup. The ultimate in projected
1975 engine system innovations is the electronic engine control system pro-
posed by Chrysler, which would integrate the regulation of ignition timing and
-------
EGR flow rate in response to engine speed, load, operating temperature,
and certain transient conditions.
In general,, the bulk of the durability emissions testing accomplished to date
has been conducted on systems which incorporate considerably less than a
full complement of the proposed engine modifications including innovative
devices discussed by the manufacturers for their projected 1975 systems.
The reason for this may be that many of these devices are still in the process
of development. It seems likely that these modifications and devices will
improve emission system performance and durability; however, it is not
possible at this time to predict the degree of improvement that might be
derived from their use.
5. EXHAUST GAS RECIRCULATION
The principal control of NOX emissions in 1975 emission control systems will
be accomplished by the use of exhaust gas recirculation (EGR), in which a
portion of the exhaust gas is recycled into the engine to lower the temperature
of combustion. All of the proposed 1975 EGR systems operate on the same
basic principle, although the designs of the different manufacturers differ in
a number of details. These include the location of the exhaust gas pick up, the
point of introduction of the recycled gas into the engine induction system, the
metering devices, and the signal source and associated control system.
While most manufacturers plan to continue with current types of EGR system
des:gns through 1975, problems have been encountered with the plugging of
orifices and/or sticking of the EGR flow control valves. These problems may
ultimately demand design modifications to the systems projected for use in
1975, depending upon EPA decisions concerning the allowable maintenance that
can be performed during certification testing.
6. OXIDATION CATALYSTS
With the exception of Toyo Kogyo, all of the manufacturers' first-choice sys-
tems incorporate an oxidation catalyst with air injection for the aftertreatment
of HC and CO emissions in the engine exhaust. Toyo Kogyo's first-choice
10
-------
systems utilize a thermal reactor device. The key to the achievement of the
1975 Federal standards, therefore, lies with the successful development of
an oxidation catalyst. However, many problem areas remain to be resolved,
such as durability, emission performance uncertainties, catalyst contamina-
tion, and safety. Industry's status with respect to these problems and plans
for their resolution will be discussed next.
6. 1 PROBLEM AREAS
6. 1. 1 Durability Problems
Oxidation catalysts pose fundamental durability problems due to inherent char-
acteristics associated with the pellet alumina substrate or the monolithic cer-
amic substrate with alumina wash coat.
Catalyst durability is composed of two separate but interrelated aspects:
emission durability and physical durability. Emission durability, or the
ability to continue oxidizing HC and CO to the required levels throughout
50, 000 miles, is most strongly impacted by decremental changes in catalytic
activity or efficiency caused by:
a. Contamination from fuel and oil additives or compounds
(e. g., lead, phosphorus, sulfur, etc.) resulting in "poisoning"
of the catalytic material.
b. Reduced alumina porosity due to phase change at excessive
temperature.
c. Alumina thermal shrinkage due to excessive temperature.
Physical durability, or the ability to maintain the substrate intact throughout
50, 000 miles, is most strongly impacted by:
a. Thermal expansion differences between monolithic ceramic
s.ubstrates and their supporting container.
b. Local melting of monolithic ceramic substrates due to
overtemperature.
c. Failure of pellet retaining screens due to overtemperature.
d. ' Cracking of monolithic ceramic substrates and break up of
pellet substrates due to vibratory loads.
11
-------
6. 1. 2 Emission Performance
Representative best examples of emission performance data for catalysts
produced by 12 different companies are shown in Table 2. These catalysts
?"
were tested in experimental systems which ranged from "conventional"
passenger cars (with the addition of a catalytic converter) to laboratory
prototype 1975 systems. Many catalysts (base metal or noble metal, pellet
or monolithic) achieved HC and CO levels far below 1975 standards when
fresh. However, when the catalysts are operated to extended mileages, the
HC and CO levels tended to rise to levels exceeding the 1975 standards.
While a number of these catalysts met 1975 HC and CO standards at greater
than 20, 000 miles, the variation of vehicle test procedures (AMA durability
runs, dynamometer runs, etc.) and the variation in test fuels and oils pre-
clude a systematic assessment of the true capability of a given catalyst under
projected EPA certification conditions. These conditions encompass the
50, 000-mile EPA certification test specifications and the use of fuel with
projected additive contaminant levels of 0. 05 gm/gal lead (max.), 0. 01 gm/
gal phosphorus (max.), and conventional lube oils. Such an assessment can
be made only with vehicles incorporating the full complement of 1975 emis-
sion control system components, tested in accordance with EPA certification
procedures.
6. 1. 3 Catalyst Contamination
Oxidation catalysts are very susceptible to contamination from sources which
can reduce or destroy catalytic activity. There is universal agreement that
the catalytic efficiency of current automotive catalysts can be lost or reduced
by reaction with, or blanketing by, lead, phosphorus, and sulfur in gasoline.
However, there is a scarcity of actual test data to establish the actual poison-
ing mechanism and the particular amount of efficiency degradation attributable
to a given contaminant level.
12
-------
Table 2. Catalytic Converter Vehicle Test Results (Representative Best Examples)
(»nd Type)
Houdry (BP)
Chemico (BP)
Engelhard (NM)
W.R. Grace (BP)
1 NMl
(IN M|
Matthey Bishop (NM)
Monsanto (BP)
Oxy -Catalyst (BP)
UOP (NP)
(NM)
(BP)
Kali-Chemie (BP)
Degussa (BP)
ICI (NP)
AC-Delco (BP)
Testing Co.
CM
EPA
Engelhard
Volvo
American Motors
CM
Ford
GM
Johnson -Matthey
Volvo
Saab
CM
CM
UOP
UOP
GM
Saab
Saab
Brit. Leyland
American Motors
Int. Harvester
Test/Car
No.
61318
1971 Olds
351 V8
351 V8
351 VB
913
1091
DOO-24
61319
17934
IA58D
1246
161
Avenger
467
9/385
61329
2541
71 Ford 351
71 Chev
933
7/301
12/301
Austin
Dll-3
D17-11
393
System Description
Noncatalyst Mods
or Components
EM+A1 + EGR
-
A!
AI * EGR
AI + EGR
EM + AI + EGR
EM + AI + EGR
EM t EGR + AI
EM + Alt EGR
AI
EM+AI+EGR + TR
EM+AI + EGR
AI
AI+EGR
AI
Elect. Inj. + AI
EM+AI+EGR
EM+AI + EGR
AI * EGR
Elect. Inj. + AI
Elect. Inj. * AI
AI
Alt EGR
AI + EGR
AI + EGR
Gatalyst
Destg.
1259 JX3-1X1
2 beds
PTX 433
STD PTX5
IMP PTX 5
PTX 416
PTX 416
PTX 423 -S
PTX -4
PTX 423 -S
PTX 5.35
PTX 5. 10
DAVEX 117
Spiral
Substrate
AEC 3A
AEC 3A
404
NBP-70194
PZ-195
PZM-7711
PZ-4-214-R-14
Emissions
Lo'*- Mileage
Test
Mileage
0
500
380
0
0
0
0
0
0
0
0
100
0
126
9
-
0
0
0
0
0
0
0
0
HC
C.25
C.15
0.16
0.32
0.22
0.11
0.09a
0. 13
0.23'
0.27
0 46
0. 11
0. 19
0.22
0.47
0. 17
-
0.38
0.19
0.. 22
0. 19
0. 19
0.23
._
0.35
CO
2.9
1.36
0.52
2. 1
0.28
K55
1.5*
1.9
3.11*
1.7
5 I
1.65
1.56
1.44
4.0
2.7
-
1.65
1.8
2.85
2.11
1.38
1.47
3.4
4.56
N0x
1.9
0.26
_
<3
<3
2.48
0.75"
1.3
1.27°
2.9
4 5
0.85
3.32
2.37
1.1
2.2
-
-
2.4
1.02
1.66
2.08
2.12
1.9
3. 11
, gm/mi
High Mileage
Test
Mileage
21,178
35,821
25,260
12,030
_
25,344
50,000
21.527
70, 000
25,000
1 6 000
24,000
9.750
5,550
10,245
21.933
-
46,301
5,900
2,580
9.200
_
32,000
20,000
HC
0.87
0.35
0.39
0.24
_
0.24
0.32a
0.55
0. 85
o!?5*
0 46
0.33
0.50
0.55
0.91
0.47
-
0.78
0.25
0.74
0.20
_
0.51a
0.51
CO
4.1
3.0
3.3
2.6
_
2.45
4.8*
5.5
8 7
7>
6 85
1.33
2.97
8.8
9.5
2.65
-
11.7
3.63
15.7
2.61
_
3.4*
8.76
NO
X
1.6
_
<3
2.2
_
1.82
2.1*
1.6
3. 5
K64°
4 0
2.01
2.87
1. 1
2.3
-
-
2.1
1.96
2.5
2.21
_
1.9*
3.0
Remarks
Test continuing
Lead-sterile fuel
over non-AMA
durability cycle
Catalyst failed at
29,900 mi
1970-type slow choke
Ford 1975 durability
program
Lead -sterile fuel
20% catalyst lost
Catalyst poisoned by
phosphorus in fuel
(4 PPM)
NOTES
2. Catalyst type symbol N = Noble metal; B = Base metal; P = Pellets; M = Monolithic
3. System mods or components; EM = Engine modifications; AJ = Air injection; EGR - Exhaust gas rscirculation
$
-------
6. 1. 3. 1 Lead Additives
The effect of lead contaminant level in the fuel on the efficiency of an
Engelhard PTX 3 catalyst is illustrated in Figure 1. Although trends between
the lead-free, 0. 035 gm/gal, and 0.07 gm/gal levels can be established, the
variability in the data precludes the establishment of an accurate correlation
of catalyst efficiency vs lead level and test duration. It should be noted that
these tests were conducted at constant engine speed and over a mild durability
cycle, and as a result the data may not be directly applicable to catalysts
installed in a vehicle and subjected to the EPA certification cycle. This
becomes evident when the data in Figure 1 are compared with the durability
data provided by other manufacturers, which generally indicate a rather
gradual degradation of catalyst/system performance with mileage accumula-
tion. This discrepancy points out the need for further systematic work in the
area of fuel contaminant effects on catalyst performance.
6. 1. 3. 2 Other Contaminants
Much less specific information is available concerning the deleterious effects
of phosphorus and sulfur on catalytic activity. Saab-Scania reports "catalyst
poisoning" with lead sterile fuel containing only 4 ppm phosphorus.
General Motors tests have been conducted with 0.02 gm/gal lead, 0. 005 gm/gal
phosphorus, and 0. 03 percent sulfur. They have seen no "significant" differ-
ences in the effects of these contaminants on base metal catalysts as opposed
to ? oble metal catalysts, although they feel that lead may be worse for base
metals. General Motors states that the temperature range of 900-1200 °F
normally seen in an automotive catalyst is the range where sulfur readily
deposits on the catalyst surface. If the converter could be designed to oper-
ate above 1300 °F all the time, sulfur problems would be alleviated. General
Motors feels that phosphorus effects are bad, regardless of the converter
operating temperature. General Motors bench test data of an Qxy-Catalyst
catalyst indicate that the sulfur build up on the catalyst is especially damaging
to carbon monoxide reactivity.
14
-------
80
o 60
-o--.£>
40
20
0
PTX3 0.2% PT
DATE COMPLETED 3-28-72
EVALUATION CONDITION
INL. CAT. TEMP. 800° F
ENGINE SPEED 1000 rpm
WITHOUT AIR
I
V V
FUEL:
Pb FREE
0.035 gm/gal Pb
0.07 gm/gal Pb
OIL: ASHLESS
DURABILITY CYCLE
MODE TEMP. TIME
1000° F
1200° F
1
2
3
4
1250° F
1200° F
14 min
15 min
6 min
7 min
I
200 400
TIME ON TEST, hr
600
Figure 1. Effect of Lead Additive on Catalyst Efficiency
-------
A chemical analysis by Ford of durability-tested catalysts revealed
contamination from lead and phosphorus in the fuel and lubricants; zinc from
lubricants; copper from an unknown source; and nickel, chromium, iron, and
manganese from a thermal reactor manifolQ liner. Engelhard durability tests
with unleaded gasoline (~0.03 gm/gal lead) resulted in. the catalyst picking up
substantial quantities of lead, zinc, phosphorus, and barium. Engelhard
associates the zinc and barium with motor oil.
Matthey Bishop feels the hydrocarbon efficiency deterioration of one of their
catalysts was due to phosphorus picked up from the engine oil.
6. 1.4 Safety
Physical failure of either monolithic or pellet catalytic converters due to
either overtemperature conditions or rupture of the canister could cause
vehicle fires, posing a serious vehicle safety hazard. Currently, there
are insufficient data available to evaluate safety aspects of catalytic
4
converters.
6. 1. 5 Technology Uncertainties
Oxidation catalyst technology is rapidly changing through intensive product
design modifications, as well as through comprehensive test and evaluation
programs, in both the catalyst industry and the automotive industry. Because
of these rapid changes, the emission data frequently reported as "latest"
results are based on catalyst materials and substrates which may in fact
bu "old technology" previously discarded by others. Due to the time delay
inherent in the relationship between the substrate-catalyst-converter sup-
pliers and the automakers themselves, it is not surprising that some prob-
lems reportedas "severe" by one company are treated as "solved" by others.
Some of the recent data presented by the catalyst makers with their latest
technology have indicated encouraging results at relatively high mileage;
however, it remains to be seen whether these catalysts can maintain good
performance when tested in a prototype emission package under realistic
driving conditions by the automobile manufacturers.
16
-------
6.2 INDUSTRY PLANS FOR RESOLUTION OF PROBLEMS
6. 2. 1 Contamination Control
The Administrator of EPA has proposed to limit the lead content of
gasoline to 0.05 gm/gal and the phosphorus content of gasoline to 0.01 gm/gal
for the unleaded grade of gasoline to be made available for automobiles utiliz-
ing catalytic converters. A similar regulation of the sulfur content in such
unleaded grade will also be promulgated if the auto companies can present
substantive evidence to establish the needed level.
All parties agree that zero levels of contaminants would be desirable, but
practical considerations, such as lead contamination in shipment, and the
need for phosphorus additives used in detergent or carburetor cleaning solu-
tions, dictate that trace levels of these contaminants will have to be "tolerated"
by the catalysts, at least in the immediate future.
The exact contribution of lubricating oil constituents to catalyst deactivation
is not evident. Ashless oils would certainly help to ensure minimization of
this contaminant but such oils have not been widely evaluated and could
adversely affect other engine parts. At present there is no clear picture of
whether or not to regulate lubricating oil composition. Therefore it would
appear that near-term automotive catalysts would have to tolerate conven-
tional lubricating oils.
6. 2. 2 Increased Catalyst Activity
An obvious approach to improving the ability of emission control systems
with oxidation catalysts to meet the 1975 standards is to increase the catalyst
activity. This is particularly true with regard to lowering the light-off tem-
perature, inasmuch as the sooner the catalyst is active after start up, the
lower the cold start emissions. It would be expected that all catalyst sup-
pliers would be actively pursuing such technological advancements to gain a
competitive advantage.
For example, in this area, Engelhard has recently related progress in
improving the catalytic activity and thermal stability of PTX-type monolithic
17
-------
catalysts. Comparison of standard versus improved PTX catalysts shows
the improved PTX catalyst has greatly increased retention of activity for
carbon monoxide and olefinic hydrocarbon oxidation even after severe thermal
aging. Johnson-Matthey, another proponent'of "noble metal/monolithic cata-
lysts, also has reported similar progress in improved catalytic activity and
high-temperature thermal stability. Both manufacturers report reductions in
light-off temperature of approximately 180-250 °F.
General Motors, currently a base metal/pellet proponent, has presented data
which indicate a basic difference in activity characteristics between base and
noble metal catalysts. They point out that the base metal catalyst starts con-
version at a lower temperature than the noble metal type and the level of
conversion gradually increases as temperature increases. On the other
hand, the noble metal catalyst exhibits a rapid increase in conversion effi-
ciency once a threshold temperature is reached (this is shown in Figure 2).
Engelhard, General Motors, and Matthey Bishop presented data showing that
prolonged exposure of noble metal catalysts to elevated temperature would
result in a gradual decrease of catalyst activity with increase in soak temper-
atures in the range of 1200-2000 °F. Similar data for base metal catalysts by
General Motors, however, indicate no significant deterioration in catalyst
activity in the temperature range between 1200 and 1500°F.
6. 2. 3 Overtemperature Protection Systems
Ovi rtemperature protection systems of several types are proposed to pre-
vent overheating of the catalyst bed, overheating of the vehicle structure,
and vehicle and external fires. Two basic approaches have been suggested by
the automotive industry and are under evaluation for providing the necessary
catalyst overtemperature protection. Both approaches employ a thermo-
couple signal to actuate the control device.
One method is to control the secondary air supply to the catalytic converter.
Without the'necessary oxidizing atmosphere, the catalyst would not function
efficiently and generate the normal temperature rise across the bed. The
18
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100
A HC
O CO
NOBLE METAL
BASE METAL
300
400
500
TEMPERATURE, °F
600
Figure 2. Conversion Characteristics of Base Metal and Noble Metal Catalysts
(Standard Bench Test Evaluation)
-------
other method is to completely bypass the exhaust gas around the catalytic
converter whenever a certain temperature, say 1500 °F, is exceeded. This
approach would fully protect the catalyst (if actuated in time), whereas the
first approach still exposes the catalyst to the gas temperature of the exhaust
flow. Current opinions of the various companies relative to the type of over-
temperature protection system proposed for 1975 vehicles vary widely.
Chrysler is developing a full by-pass system, Ford plans to have secondary
air control, Nissan is considering both approaches, General Motors plans to
incorporate a choke which fails in the open position, and Volvo and British
Leyland plan to have a warning system only.
In addition to these two protection system approaches, other refinements/
devices are also being considered, including placement of the converter fur-
ther downstream from the exhaust manifold to reduce inlet gas temperatures,
and the use of an air dump valve during periods of vehicle deceleration to
minimize the catalyst bed temperature.
With regard to vehicle structure protection, heat shields are proposed for
use between the converters and the vehicle. General Motors proposes insula-
tors on top and bottom of their converter to protect against vehicle overheat-
ing as well as grass fires.
6.2.4 Attrition Control
Advances in both catalyst substrate properties and canister design features
ar . required to meet the durability requirements of the 1975 emission
standards.
Early pellet substrates were subject'to severe breakup or attrition, as well
as thermal shrinkage. Data from a number of manufacturers indicate that
pellet attrition has been substantially reduced and further improvements may
be possible.
Similarly, Engelhard has described improved catalyst properties leading to
4
increased high-temperature activity which may result in improved durability
of the alumina wash coat of the monolith catalyst.
20
-------
The wide spectrum of catalytic converter mechanical failure types and modes
experienced to date illustrates clearly that the canister (or container) design
must protect the ceramic substrates (pellet or monolith) from excessive
vibratory loads and stresses. In view of the inherent fragility of ceramics,
such failure can be ascribed to deficiencies in the canister support design.
Aside from General Motors (AC-Delco) and Universal Oil Products (Mini-
Verter), most companies had exceedingly poor results with pellet converters.
For example, Chemico requires pellet addition (due to attrition) at 3000- to
8000-mile intervals.
General Motors claims that its horizontal-bed converter design, in combina-
tion with thermal shrinkage improvements in the pellet substrate, has solved
the attrition problem. If so, the internal pellet support arrangement (top and
bottom retaining screens, etc.) is such as to accommodate the relative ther-
mal expansion of the pellets, retainers, and canister shell while holding the
pellets in sufficiently close-packed proximity to prevent vibratory movement
of the pellets against each other.
Early monolithic converters apparently were little more than a sheet metal
canister, housing the ceramic core. In such an arrangement, it would be
expected that differential thermal expansion and vibratory loads would
severely damage the catalyst, as has been evidenced. A number of promis-
ing design approaches, however, have been advanced for solving these prob-
lems. These include shock mounting of the core in the canister, compensat-
ing for differential thermal expansion, and preventing axial movement between
core and canister.
6. 2. 4 Platinum Availability
The question of platinum availability has been an issue of concern for some
of the automobile and catalyst manufacturers. A recent study conducted
by Johnson-Matthey, which is associated with Rustenburg Platinum Mines,
Limited, a major producer of platinum in the Western world, has indicated
that sufficient platinum will be available to satisfy the combined demand of
21
-------
the automotive industry and all other platinum users. Engelhard has also
stated previously that adequate platinum supplies will be available to satisfy
the demands of the automotive industry provided that platinum from used cata-
lysts is recycled.
7. THERMAL REACTORS
The thermal reactor is a high-temperature chamber which replaces the con-
ventional engine exhaust manifold. Hot exhaust gases from the engine enter
the thermal reactor, which is sized and configured to increase the residence
time of the gases and permit further oxidation reactions, thus reducing the
HC and CO concentrations.
Whereas both rich and lean reactors have been considered and evaluated for
use in 1975 emission control systems, all of the reactors presently being
tested by the automobile manufacturers as potential 1975 candidate devices
are designed for fuel-rich engine operation. These systems require the addi-
tion of secondary air (usually injected at the engine exhaust port) to enhance
the oxidation reactions in the reactor.
With the exception of Toyo Kogyo, no manufacturer proposes to use a full-
size thermal reactor device as a first-choice system component for 1975.
The General Motors and Chrysler systems utilize a partial (i. e., a small,
simplified) reactor which serves primarily as a quick-heat device for rapid
warmup of their catalytic converter. The Toyo Kogyo reactor is a prime
emission control component of its rotary engine system; in addition, the
reactor is one of several systems being evaluated for use on its 1975 recipro-
cating engine. Several manufacturers are evaluating reactor devices as 1975
alternate system components.
Thermal reactor problems identified by the various manufacturers encompass
the following: lack of sufficient emission control capability, packaging diffi-
culties, excessive underhood temperatures, and lack of sufficient reactor
and secondary air injection system durability. In addition to these problems,
severe engine damage has been caused by reentry of metal oxide particles
22
-------
from the reactor core material through the EGR system into the engine
lubricating oil. A recent study by Ford implies that an incompatibility
may exist between thermal reactors and catalytic converters when used
together. Material deposits have been found in the catalyst which are thought
to originate in the reactor liner. These deposits may contribute to the exces-
sive deterioration observed in a number of thermal reactor/catalytic conver-
ter emission control systems.
8. SECONDARY AIR SUPPLY
Although secondary air injection at engine exhaust ports has been widely used
as an independent control device for the suppression of HC and CO emissions
since 1966, it is not being given serious consideration by any automobile man-
ufacturer as a sole system for meeting the 1975 standards.
In aftertreatment devices for HC and CO control, such as catalytic conver-
ters and thermal reactors, sufficient oxygen is needed to promote oxidation
of the pollutants. The oxygen required is provided by secondary air supplied
by an engine-driven air pump.
Generally, little more than passing mention of the use and type of air pump
was made by the automobile manufacturers in discussing their projected 1975
emission control systems. Pump durability and pump noise are frequently
identified as problem areas; the durability problem appears to be particularly
troublesome. However, no manufacturer classifies any part of the air injec-
tion system as critical for 1975.
9. EMISSION GOALS
9. 1 GENERAL
In order to comply with the 1975 emission standards on production vehicles at
50, 000 miles, the automobile manufacturers must demonstrate substantially
lower emission goals on low mileage engineering prototype vehicles to account
for a number of parameters affecting emission control system performance.
These parameters include the emission control system deterioration factor (DF)
23
-------
the prototype-to-production slippage factor (PPS), and, in case emission
averaging is not permitted, the production quality control factor (QCF).
Based on these definitions, the low mileage emission goals for engineering
prototype vehicles are computed from the following equation:
A, M , .
Mgoal = DF X PPS X QCF ' gm/mi
where M represents the 1975 HC, CO, and NOX emission standards and DF
represents the system deterioration factor between low mileage and 50, 000
miles. To minimize "green" engine/control-system effects, EPA has
selected the 4, 000-mile point as the low mileage reference value. It should
be noted that deterioration factors must be used with care. In general, deter-
ioration factors determined for one type of vehicle /emission control system
K
are only applicable to similar configurations.
The in-house emission goals established by the various manufacturers for
reciprocating spark ignition engine-powered vehicles are presented in
Table 3. Also shown are the emission goals selected by Toyo Kogyo and
Mercedes-Benz for rotary engine-powered vehicles. Mercedes-Benz has
stated that the 220D diesel vehicle will probably meet the 1975 standards but
did not provide emission goals for diesels. With the exception of one set of
numbers presented by General Motors, the emission goals established by the
automobile manufacturers are based on the emission averaging concept
(QCF = 1. 0). Another set of emission goals presented by General Motors is
listed in the table. This set is based on the assumption that 99..5 percent of
the production vehicles meet the 1975 standards at 50, 000 miles. This
assumption results in such extremely low HC and CO emission levels that it
is doubtful whether these values can be attained with current spark ignition
engine emission control system technology.
24
-------
Table 3. Summary of Low Mileage Emission Goals
for Projected 1975 Control Systems
Selected
Manufacturers
American Motors
General Motors
(No catalyst
change)
(Catalyst change,
25, 000 mi)
(99.5% of cars
meeting standard
at 50, 000 mi)
Foreign
Manufacturers
1C engine, catalyst
(and thermal
reactor)
1C engine, thermal
reactor (recipro-
cating and rotary)
Emission Control
System
EM+EGR+AI+OC
EM+EGR+AI+PTR+OC
Same
Same
EM( +EGR) +AI+(TR) +OC
EM(+EGR)+AI+TR
Emission Goals gm/mi
HC
0.10-0. 15
0.2
0.27
0.07
0. 14-0.2
0.26-0.29
CO
1.50-2.55
1.7
2.27
0.71
1.2-2.0
2.2-2.3
NOx
2.2
2.07
2.07
1.16
1.2-2.3
2.0-2.3
AI = Secondary air injection
EM = Engine modifications
EGR = Exhaust gas recirculation
TR = Thermal reactor
OC = Oxidation catalyst
PTR = Partial thermal reactor
Most manufacturers have assumed HC and CO emission deterioration factors
of 2.0 for systems incorporating catalytic converters. Based on the available
test data, this assumption appears too optimistic, although further improve-
ments in the carburetion, choke, and ignition systems, and in catalyst perfor-
mance might be achieved in time for use in 1975 vehicles. Toyo Kogyo has
selected a HC and a CO deterioration factor of 1. 3 for systems incorporating
a thermal reactor only. This is a lower factor than that selected for its
25
-------
systems incorporating a catalytic converter. NO deterioration factors
3t
assumed by the manufacturers vary between 1. 1 and 1. 8. It is believed that
these levels are attainable, although EGR system maintenance may be
required to accomplish this.
The emission goals presented by the automobile manufacturers are based on
the ground rule that catalyst replacement is not permitted during the 50, 000-
mile test. If catalyst replacement were permitted at intermediate mileage
points, the emission goals could be relaxed somewhat. The degree of relaxa-
tion is primarily determined by the shape of the emission-versus-mileage
curve which is generally different for different vehicle/control system com-
binations. General Motors is the only manufacturer that has provided emis-
sion goals for 25, 000-mile catalyst replacement intervals.
9. 2 DETERIORATION FACTOR
The deterioration factor (DF) of the emission control system is primarily
responsible for the manufacturer's stringent emission goals. This factor
accounts for the emission increase which results from the performance
degradation with mileage accumulation of all components utilized in the sys-
tem including the engine, the catalyst, and other aftertreatment devices. In
general, the catalytic converter is the critical component. Catalyst degrada-
tion is the result of poisoning of the active elements by lead, phosphorus,
sulfur, and oil additives, and of attrition and exposure to overtemperature
cond uons. Those manufacturers considering thermal reactor systems expect
their deterioration factors to be lower than those of catalyst systems.
Many of the high mileage tests of emission control systems incorporating a
catalyst indicate a rather gradual deterioration of emission performance with
mileage accumulation. This is illustrated by most of the HC and CO data pro-
vided by American Motors, General Motors, Engelhard, and Ford and by the
HC data presented by Matthey Bishop. These data suggest that deterioration
factors derived for a particular vehicle/control system are only valid for
similar configurations and operating conditions. For example, the
26
-------
deterioration factors derived from a catalyst system operated under
idealized conditions (lead-sterile fuel and moderate catalyst temperature)
are not necessarily applicable to similar vehicles which are subjected to
commercially available "lead-free" fuel and/or more severe durability or
customer driving patterns.
Test data provided by Ford from the 1974 California catalyst-only vehicle
fleet indicate rapid degradation of the emissions during the first few thousand
miles on two of the five vehicles. In both instances the emissions remained
essentially constant from this mileage point up to 50, 000 miles. This trend
is contradictory to other Ford durability data.
The deterioration factors derived from the high mileage emission data pro-
vided by the automobile manufacturers are summarized in Figure 3. Although
it is not possible to precisely correlate these data, it is apparent that the
degradation has generally been more severe for systems with low initial (low
mileage) emissions.
Since the emission control systems projected for use in 1975 vehicles will
incorporate improved carburetion, choke, and ignition systems as well as
improved (stabilized) catalytic converters, the emissions and the deteriora-
tion factors of these systems should be lower than currently indicated. It
appears that this assumption was included in the considerations made by the
automobile manufacturers in establishing their deterioration factors.
9. 3 PROTQTYPE-TQ-PRODUCTION SLIPPAGE FACTOR
The prototype-to-production slippage factor (PPS) is defined as the ratio of
the average emissions of production vehicles compared with the emissions of
identical engineering prototype vehicles. Based on past experience, the
emissions from production vehicles are on the average higher than those of
the prototype because of production tolerances and adjustments made in the
final desig"n and fabrication of certain components. Although these factors
are known for current vehicles, it is difficult to make accurate predictions
for future designs. Most of the manufacturers project PPS factors between
1. 1 and 1. 25.
27
-------
u *
u.
11 3
o 0
u. §
o m o
P
1|
LU
O
AMC (CVS-CH)
O CMC (CVS-CH,
D FORD (CVS-C)
0 IH (CVS-CH)
O
o
0
o
A
1
A MITSUBISHI (CVS-CH)
Bst) V NISSAN (CVS-C)
O MATTHEY BISHOP (CVS-CH)
6 HOUDRY (CVS-C)
0
0 D V
°Vo *°
° °8
0.2 0.4 0.6 0.8 1.0 1.2
HC EMISSIONS AT 4000 mi, gm/mi
o
ca
5« 2
o
u
O
1.4
D
O &
O
2 4 6 8 10 12
CO EMISSIONS AT 4000 mi, gm/mi
14
Figure 3. Deterioration Factors vs Emissions at 4000 Miles
28
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9.4 PRODUCTION QUALITY CONTROL FACTOR
The production quality control factor (QCF) accounts for the differences
between the average emissions of a certain vehicle model and the maximum
emissions of a specified percentage of the total vehicle population of that
model. The effect of the QCF on the emission goals is illustrated in
Figure 4, which shows the HC and CO emission distributions from 1971
General Motors production vehicles. Although these curves may not be
applicable to 1975 model vehicles, they are presented here to show trends.
As indicated, extremely low emission goals would be required if a high per-
centage of the vehicles would have to meet the standards. For example, a
QCF of approximately 2. 8 for HC and 3. 1 for CO would be required
to achieve compliance with 99. 5 percent of General Motors vehicles in
Figure 4. This results in correspondingly tighter emission goals. Con-
versely, if the emission averaging concept is adopted, the QCF has
no effect on the emission goals (QCF = 1. 0).
10. INTERIM STANDARDS
All thirteen automobile manufacturers appearing as witnesses at the EPA
Suspension Request Hearings have asked for a one-year suspension of the
1975 Federal emission standards and adoption of less stringent interim
standards. In justifying their request, the automobile manufacturers con-
tend that the technology is currently not available to achieve the 1975 stan-
dards on spark ignition reciprocating engine-powered production vehicles.
Furthermore, the automobile manufacturers are extremely reluctant to mass
produce a catalytic emission control system without having successfully
demonstrated vehicle/control system safety, performance, and durability.
To date, there are no data available that prove that mass-produced vehicles
can meet the 1975 emission standards at 50, 000 miles when operated under
conditions simulating customer driving patterns.
The interim standards proposed by the automobile manufacturers and a num-
ber of the catalyst suppliers are presented in Table 4. All of these interim
29
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4.0
3.0
HC EMISSION LEVEL
(GRAMS PER MILE)
2.2
2.0
1.3
1.0
LIMIT
95% OF CARS'
V-TESTED ARE
.BELOW LIMIT
5% OF CARS
TESTED
0 10 20 30 40 50 60 70 80 90 100
PERCENT OF CARS TESTED
60r
CO EMISSION LEVEL
(GRAMS PER MILE]
V ' :88%OFCARS
;ARE TESTED
' s 'iBELOW LIMIT
12% OF CARS
TESTED
0 10 20 30 40 50 60 70 80 90 100
PERCENT OF CARS TESTED
Figure 4. HC and CO Emission Levels from 1971 California Car Production
Audit (1473 Cars Tested) (GM Production Vehicles)
30
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Table 4. Interim 1975 Emission Standards Proposed by Manufacturers
Manufacturer
Emission Control
Concept
I. DOMESTIC AUTOMOBILE MANUFACTURERS
American Motors
Chrysler
Ford
General Motors
International Harvester
Engine Modification
Engine Modification
Oxidation Catalyst
Engine Modification
Oxidation Catalyst
II. FOREIGN AUTOMOBILE MANUFACTURERS
British Leyland
Daimler-Benz
Nissan
Saab-Scania
Toyo Kpgyo
Toyota
Volkswagen
Volvo
Engine Modification
Engine Modification
Diesel Engine
Without Catalyst
Engine Modification
Engine Modification
Engine Modification
Rotary Wankel Engine
With Thermal Reactor
Engine Modification
Engine Modification
Engine Modification
III. CATALYST MANUFACTURERS
Chemico
Engelhard
W. R. Grace
Universal Oil Products
Catalyst Addition
Catalyst
Catalyst
Catalyst
Emissions, gm/mi
HC
3.4
1. 5 to
2.0
1. 6
1.5
3.4
1. 0 to
1. 15
3. 4
1. 5
0. 41
3.4
3.4
-
(0.41)
3. 4
3.4
3/4
CO
39
20 to
25
19
19
39
12 to
20
39
20
3. 4
39
39
-
(3.4)
39
39
39
NO
X
3. 0
2. 5 to
2.0
2. 0
3. 1
3.0
3. 0 to
1.75
3. 0
1.5
3. 1
3.0
3.0
-
(3.1)
3.0
3. 0
3.0
Technology to meet 1975
standards available
1975 Standards or slightly
higher
0. 6 to
0. 8
0.96
7 to
10
7.99
-
Manufacturers' Remarks
1974 Standards
To be selected within that range
Some models possibly without
catalyst
1974 Standards
Either combination feasible
1974 Standards
Meets 1975 Standards
1974 Standards
1974 Standards
Not selected
Good chance to meet 1975 Standards
1974 Standards
1974 Standards
1974 Standards
No test data supporting claim
-------
standards are based upon the concept of emission averaging and, in the case
of Ford, upon the satisfactory resolution by EPA of several regulatory issues,
including fuel specifications, vehicle maintenance, and special allowances for
methane in the exhaust. Ford proposed that the hydrocarbon composition of
the exhaust should be considered in evaluating vehicle compliance with the
standard. The methane reactivity was specifically mentioned, since meth-
ane's role in the smog formation process is negligible. Methane conversion
efficiency of the catalyst is low, compared with other more reactive hydro-
carbons. If reactivity were considered, catalysts would appear to be more
effective in reducing hydrocarbons in the exhaust.
With the exception of Ford and International Harvester, which propose to use
oxidation catalysts, the remaining automobile manufacturers' suggested
interim standards -will be achieved by engine modifications, including im-
proved carburetion, choke, and ignition systems.
With the exception of Chrysler, Ford, International Harvester, and Daimler-
Benz, all automobile manufacturers have proposed to adopt the 1974 emission
standards for 1975 spark ignition reciprocating engine-powered vehicles,
primarily for the following stated reasons:
a. Promulgation of interim standards lower than the 1974 standards
has little effect on improving air quality, as shown by the National
Academy of Sciences.
b. Adoption of more stringent standards would tend to dilute current
emission control system development efforts because the auto-
, makers might then be inclined to select 1975 systems using
devices such as thermal reactors, which have little chance of
ever meeting the 1976 NOX standard.
c. Excessive risk and system cost.
The interim standards proposed by Chrysler and Daimler-Benz are of the
order of 50 percent of the 1974 standards. Both companies .would attempt to
achieve these levels by means of engine modifications only, possibly with the
use of secondary air injected into the exhaust manifold. This basic approach
is considered to be desirable because it minimizes the raw engine emissions.
32
-------
As a result, potential catalyst heat load problems will be reduced in future
systems incorporating catalysts.
Ford and International Harvester propose interim standards somewhat below
those recommended by Chrysler and Daimler-Benz. Both Ford and Inter-
national Harvester project the use of oxidation catalysts in their interim sys-
tem vehicles but Ford believes that the catalyst might be omitted on some
Ford models. In this case, catalytic systems could be introduced more grad-
ually to gain the required field experience and to minimize the risk. Since
the emissions from the Ford 1972 and 1973 development fleets and the raw
engine emissions from the Ford Riverside fleet are substantially lower than
the 1974 standards, the prospects appear favorable for this approach. To
further investigate this matter, a review was made of 1972-73 certification
test data from American Motors, Ford, General Motors, and Nissan. Adjust-
ments were then made to these data to account for emission deterioration,
production slippage and, where applicable, conversion to the 1975 test proce-
dure. Based on the resultant analysis, it appears that the following emissions
can be achieved with available 1972 technology without the use of a catalyst:
2.5 gm/mi HC, 2.5 gm/mi CO, and 3.0 gm/mi NOX, respectively.
With the likelihood of further emission reductions resulting from carburetor
and ignition system improvements, it is believed that emission standards
more stringent than the 1974 standards are feasible for 1975. Further emis-
sion reductions are possible by incorporation of catalysts currently under
development. Even with conservative estimates of catalyst efficiencies at
50,000 miles, the HC values shown above could be reduced by approximately
30 percent and the CO values by about 40 percent, respectively. This assumes
no replacement of the catalyst. If catalyst replacement at 25,000 miles is con-
sidered, the above percentage reductions would be changed to approximately
55 percent and 60 percent for HC and CO, respectively.
Catalyst replacement at 20,000 or 25,000 miles has been discarded by Ford
on the basis of data which lead it to believe that catalyst deterioration is
primarily confined to the low mileage range. However, the Ford position
33
-------
appears questionable in view of the vehicle durability test data submitted by
American Motors, General Motors, Matthey Bishop, and other data from
Ford. Most data from these manufacturers indicate a rather gradual emis-
sion and catalyst effectiveness deterioration with mileage accumulation.
None of the other manufacturers has provided information regarding cata-
lyst replacement between 0 and 50,000 miles.
11. PRODUCTION LEAD TIME
Each automobile manufacturer has identified one or more factors which con-
trol or define his lead time requirement for the development of production
tooling and facilities needed to mass produce 1975 emission control system
components. In each case, the most critical items cited were the fabrication
of the catalytic converter and the completion of durability tests currently
being conducted for the verification of the complete emission system design.
Since the catalytic converter appears to be a pacing production development
item with which all of the manufacturers must contend, it serves as a con-
sistent basis for examining and comparing production schedules and lead
times among the different manufacturers. The data available for this com-
parison are shown in Figure 5. In general, the agreement of the catalytic
converter production milestones among the various automobile manufacturers
is good; the overall lead time requirements range from 25 to 28 months.
If the lead time reference point is fixed at the date of firm commitment, it is
sei n that the lead times estimated to be required by the various catalyst sup-
pliers vary in a narrow range from 21 to 25 months. Allowing for the fact that
production catalysts must be available at the manufacturer's plant in advance
of first vehicle production, the automotive manufacturer's lead time require-
ment would be expected to be approximately 2 years. This is consistent with
the previously noted lead time requirements of 25 to 28 months cited by the
automobile manufacturers. Since the schedules of the automotive manufacturers
are in good general agreement, it is concluded that there are no gross
34
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Oo
(SI
AMERICAN MOTORS
CHRYSLER
FORD
GENERAL MOTORS
VOLVO
VOLKSWAGEN
CY 72 CY 7
2468 10 12 246
C
I
A C
I i
3 CY 74
6 10 12 2 4 68
F
D E F
i i
-^LEAD TIME REFERENCE POINT
ABC D E F
I^dZ '
A B
i i
E F
f T~ i
A C
i i
B
I
1 i i i i 1 i i i i
D E F
i i i
D F
i
i 1 iii i i
30
25 20 . 15 10
MONTHS TO VEHICLE PRODUCTION
A
B
C
PRODUCTION DESIGN PRELIMINARY
APPROVAL
TOOLING AND FACILITIES
PROGRAM APPROVAL
FACILITIES AND LONG LEAD TIME
PARTS/EQUIPMENT CONTRACT
START DURABILITY AND
CERTIFICATION TESTS
START VEHICLE PILOT PART
PROGRAM
D
E
F - START VEHICLE PRODUCTION
Figure 5. Significant Milestones for Catalytic Converter Production
(Data Supplied by Automobile Manufacturers)
-------
inconsistencies among or between the lead time specifications of the suppliers
and manufacturers.
Ford has contracted with Eng'elhard Industries for supplying catalysts to be
used in the Ford emission control system arid has provided financial backing
of up to $4.9 million for facilities and equipment. This relationship repre-
sents the only case to date of a contractual commitment between an automo-
bile manufacturer and a catalyst supplier for production facilities.
All manufacturers have indicated that their current schedules represent an
accelerated work effort in order to develop production facilities in time for
the 1975 model year. Additional schedule compression holds higher risks
for the automobile manufacturers because of the resulting major reductions
in the time allowance set for correcting problems in production hardware
design or assembly line operations; this effect is only correctable to a degree
through the use of labor on an overtime basis, which in turn raises product
cost. Some catalyst suppliers have estimated an ability to further compress
their schedules by 3 to 6 months, but with corresponding increases in unit
costs from 3 to 12 percent.
12. MAINTENANCE, SAFETY, AND COST
Recognizing that the 1975-1976 emission goals may never be effectively
achieved unless emission control systems maintain their efficiency in ser-
vice, EPA has indicated that they would consider approving increased mainte-
nance of the emission system components under certain guidelines. Difficulty
in meeting the 50,000-mile requirement has led to the consideration of per-
mitting more maintenance and repair over the durability test mileage, pro-
vided that failure or deterioration of the component would, by. appropriate
design, "induce" the car owner to have the defect remedied. This approach
is fundamentally difficult to implement because many types of emission con-
trol system failures tend to improve vehicle performance and driveability.
Proposed fail-open modes for the EGR valve are found to pose safety hazard
problems, while the cost of catalyst replacement tends to militate against the
36
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success of an approach permitting voluntary refurbishment of the system.
In summary, no effective approach has yet been found to ensure that emission
systems \vill continue to function properly in service.
Safety issues concerned with the 1975 emission control systems include poor
passing performance, increased fire hazard, and possible catastrophic fail-
ures of critical vehicle components due to increased underhood and exhaust
temperatures associated with the thermal reactor and/or catalytic converter.
The performance problem has led a number of manufacturers to consider
dropping low-power economy models in order to retain safe driveability
throughout their product line. Currently, no one using the overtemperature -
controlled catalytic converter by-pass valve is confident that it represents a
satisfactory solution to the fire hazard problem.
The major cost factors associated with the 1975 emission control system
package relate to increases in the purchase price of the car, increases in
vehicle lifetime maintenance costs, and increases in fuel costs. Projections
of sticker price increases for 1975 emission system cars (using a 1968 base-
line) range from $255 to $412 among the various domestic manufacturers.
13. REGULATORY PROBLEM AREAS
In developing engineering goals for the 1975 emission control systems, the
automobile manufacturers had to make a number of assumptions related to
vehicle durability and to certification test procedures. These assumptions,
which require action by EPA, include emission averaging for certification
and assembly line vehicles, fuel contaminant regulation, methane allowance,
and maintenance, warranty, and recall procedures.
All manufacturers have assumed that emission averaging will be permitted
by EPA for both certification and assembly line vehicles. It is the consensus
of the industry that meeting 1975 emission standards with every vehicle is not
practical because of variations in the production tolerances and the test data.
A number of manufacturers have recommended that the fuel contaminant
levels be limited to values below those permitted by the proposed EPA fuel
37
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additive regulations in order to prevent catalyst poisoning. In addition, the
establishment of maximum sulfur and other additive levels in fuel is con-
sidered desirable. Test data by General Motors indicate that catalyst dam-
age occurs with fuels containing more than 0. 02 gm/gal lead, 0. 005 gm/gal
phosphorus, and 0. 03 percent sulfur. Test fuel volatility is another impor-
tant issue which deserves consideration by EPA. As shown by General
Motors, modifications in the fuel volatility can result in substantial reduc-
tions of CO emissions during the cold start phase of the certification cycle
without adversely affecting vehicle driveability. Since methane is essentially
nonreactive, Ford proposes establishment by EPA of a methane allowance
in interpreting HC emission test data. This approach would be particularly
significant for control systems using platinum catalysts since the methane
conversion efficiency of these catalysts is generally low.
The question of what constitutes a meaningful certification cycle for vehicle/
control systems utilizing a catalyst has been raised by a number of automo-
bile manufacturers. Chrysler has stated that the catalyst temperatures
achieved during the EPA certification cycle are substantially lower than those
obtained under high-load and/or customer driving conditions. As a result,
vehicle/control system safety and catalyst durability cannot be adequately
evaluated with the current certification procedure.
38
-------
1. INTRODUCTION
The purpose of this report is to. present'.a.compilation and evaluation of all
available information pertaining to the assessment of the technological progress
by the automotive industry toward meeting the 1975 Federal emission standards
for light duty'vehicles. These 1975 standards are:
HC (hydrocarbons) 0.41 gm/mi
CO (carbon monoxide) 3.40 gm/mi
NO (oxides of nitrogen) 3.10 gm/mi
To fulfill the objectives of this study, the work effort was composed of two
areas: data compilation and data review, summarization, and evaluation.
A compilation was made of all information available from three sources:
(1) the manufacturers' applications for suspension of the 1975 emission
standards, (2) the testimony and supplementary material presented by the
witnesses at the April 10-28, 1972 EPA Suspension Request Hearings, and
(3) the documents submitted by industry in response to the September 1971
EPA technology survey questionnaire. A review, summarization, and evalua-
tion of all data acquired were performed. First-choice emission control
systems, possible alternate systems, unconventional engine designs, and
emission control system components were included in the study. Emphasis
has been directed toward low and high mileage emissions; component and
system durability characteristics--in particular, catalytic converters; and
factors affecting emission goals and interim standards. In addition, the
problem areas related to the emission control systems and components were
identified and the manufacturers' plans for resolution were evaluated.
The body of the report is based on information obtained from the automotive
industry, including domestic and foreign automakers, catalyst manufacturers,
and catalyst component suppliers. The appendix includes the highlights of
the statements made by nonautomotive industry witnesses at the April 10-28
EPA Suspension Request Hearings.
1-1
-------
2. CANDIDATE 1975 EMISSION CONTROL SYSTEMS
2. 1 SUMMARY DISCUSSION
The discussion of candidate 1975 emission control systems presented in the
following sections of this report is based on information from three sources:
the manufacturer's applications for suspension, the testimony and supple-
mentary material presented at the April 10-28 Washington, D. C. hearings,
and the material submitted in response to the September, 1971 EPA tech-
nology assessment survey questionnaire. The suspension applications were
a prime source of material on Ford, Chrysler, General Motors, Interna-
tional Harvester, and Volvo. The hearing testimony provided supplementary
data on these manufacturers, and, in addition, yielded information on the
first-choice systems for American Motors, British Leyland, Daimler-Benz,
Nissan, Saab, Toyo Kogyo, Toyota, and Volkswagen. The 1971 EPA survey
provided the data base for the other auto manufacturers discussed in this
section: Alfa Romeo, BMW, Citroen, Honda, Mitsubishi, Renault, and
Rolls-Royce.
The 1975 emission control system is exemplified by the following package of
components and engine modifications:
Oxidizing catalytic converter
Air injection
Exhaust gas recirculation (EGR)
Carburetor modifications
Ignition system modifications
With the exception of Toyo Kogyo which utilizes a thermal reactor, all of
/the manufacturers' first-choice systems incorporate an oxidizing catalytic
converter with air injection to promote the oxidation of unburned hydro-
carbons (HC) and carbon monoxide (CO) of the engine exhaust.y The catalytic
1 converter type which appears most frequently among the selected
Z-l
-------
first -choice systems is the noble metal /monolithic catalyst exemplified by
the Engelhard PTX design. General Motors, International Harvester, and
a number of other manufacturers have selected the base metal/pelletized
(AC-Delco) type of converter as a first-choice design. In many cases a
firm, decision as to catalyst type has not been made and several systems are
being tested and evaluated concurrently.
Nearly all of the first-choice systems employ EGR for the control of oxides
~\
of nitrogen (NO ). ) However, most British Leyland and the Toyo Kogyo and
x /
Saab vehicles exported to the U.S. are said to be capable of meeting the 1975
3.10 gm/mi NO standard without EGR.
ji
In addition to the aftertreatment systems delineated above, a number of
manufacturers, including Chrysler, GM, and Ford, utilize a partial thermal
reactor in place of the conventional exhaust manifold, primarily to provide
rapid warmup of the catalytic converter under cold start conditions.
ff
jfkDarburetion system modifications-thattha-ve-bTe'en identified for first "choice
range from complete redesigns, utilizing new concepts, to minor
improvements to the current conventional systems. These modifications
are generally directed toward improving the precision and stability of the
air /fuel raticraand also include such features as altitude compensation, quick
release choice devices, and induction manifold heating. All of the domestic
and several of the foreign manufacturers propose, or have in development,
V^-electronic (breakerless) ignition systems which are targeted for inclusion in
first-choice system. These systems generally provide an improvement
fh spark-timing precision, consistency and reliability.
The most pervasive problem in the industry relative to 1975 emission control
systems appears to be the lack of adequate durability in the catalytic con-
verters currently under test. Catalyst durability is composed of two aspects:
physical durability and emission durability. For monolithic designs, the
physical aspect of the problem is symptomized by cracking and local melting
2-2
-------
of the catalyst substrate, due to vibratory loads and overtemperature. For
pellet-type systems, the problem is exhibited as a loss of catalyst material,
caused by brittleness of the pellets and/or deficiencies in the design and
construction of the support grids. Physical breakdown appears to be partic-
ularly severe in 4-cylinder engine systems because of characteristically
high vibrations. Canister deformation and rupture failures have occurred
with both types of converter designs.
Einission durability is most strongly impacted by a loss of catalyst efficiency
with accumulated mileage without mechanical deterioration. The problem
has several causes, including poisoning of the catalyst due to small quantities
of lead, sulfur, or phosphorous in the fuel and/or loss of catalyst surface
area due to overheating. The overheating effect appears to be primarily
related to rich air/fuel operation and may be encountered under various
engine/vehicle operating conditions including acceleration, deceleration,
choking, high-power operation, and malfunctions of different types.
In addition to the catalytic converter, durability problems with other 1975
emission system components are reported. Notable among these are EGR
valves and thermal reactors.
Other problems which appear to be characteristic of 1975 emission control
systems are degradation of vehicle driveability, loss of vehicle performance,
and deterioration of fuel economy. Driveability problems reported encom-
pass the following: loss of cold start driveaway capability, stumbles, stalls,
inadequate acceleration, difficulty in hot starting, rough idle, surging, hesi-
tation, and backfire. Power losses and losses in fuel economy (relative to
1972 vehicles) range from 10 to 20 percent for both parameters.
The catalytic converter durability problem is being treated in several ways.
One of these is characterized by improvements in the basic design of the con-
verter (by the catalyst supplier); another technique involves improvements
in the precision control of the converter operating environment (by the
2-3
-------
auto manufacturer). Basic converter design innovations include the use of
stacked (layered) and extruded monolithic substrates having superior physical
properties to first-generation rolled or spiral designs, improved pellet con-
figurations and grid systems , and better shock-mounting and support arrange-
ments. Limit regulation of air /fuel mixtures, improved carburetion, and
converter by-pass overtemperature protection systems are some of the
techniques under development for controlling the quality of the exhaust flow
to the catalyst.
With regard to the degradation of vehicle driveability, performance, and fuel
economy, improvements are being sought by modifying the design of the fuel
metering, induction, and ignition systems. Electronic engine control, which
integrates the adjustment of ignition timing, air /fuel ratio, and EGR flowrate
with respect to engine load and RPM, may provide the means to achieve an
optimized balance of exhaust emissions versus vehicle performance and
economy. Electronic engine control is a feature of the Chrysler first-choice
system.
The emission performance of the 1975 systems is categorized in terms of
low and high (4000 ) mileage accumulation. Many of the manufacturers' low
mileage test results fall well within the 1975 standards; most of these sys-
tems drift outside the limits of the standards at low levels of mileage accumu-
lation. In general, zero-mileage vehicles do not meet the manufacturers'
nal engineering emission goals.
The status of high mileage emission level capabilities for 1975 first-choice
systems may be gauged from the summary of best high mileage emission
results presented in Table 2-1. The maximum mileage accumulated with all
three pollutants within standards was 32,000 miles, achieved by an American
Motors Javelin (3000-lb, 6-cylinder, 258-CID engine) equipped with an
AC-Delco base metal, pelletized catalytic converter (Car D17-11). This
system is continuing to accumulate mileage (EPA durability driving schedule).
2-4
-------
Table 2-1. First-Choice Systems, Summary of Best High Mileage Emission Results
Manufacturer
Test or Car N'o.
First-Choice System Components
Mileage
1975 CVS-CH
Emissions, ^m/
HC
CO
NO
Remarks
American Motors
American Motors
Chrysler
Ford
General Motors
International Harvester
Alfa Romeo
BMW
British Leyland
Citroen
Daimler-Benz
Honda
Mitsubishi
Nissan
Renault
Saab
Toyo Kogyo
Toyota
Volkswagen
Volvo
D17-11
DOO-24
698
Ford »1
2222
Austin
Rib
75-A
OB44085
EM + EGR + AI + OC
EM + EGR + AI + OC
EM + EGR + AI + PTR + OC
EM + EGR + AI (+ TR) + OC
EM + EGR + AI * PTR + OC
EM + EGR + AI + OC
Not defined
EM + EGR + AI t OC
EM + AI + OC
Not defined
EM + EGR + AI + OC
Not defined
EM + AI (+ TR) + OC
EM + EGR + AI + OC
AI + OC
EM + AI + OC
(EM) + AI + TR
C- OC for reciprocating)
EM + EGR -> AI + OC
EM (+ EFI) + EGR + AI + TR + OC
EM + EGR -f AI + OC
32,000
50,000
43,000
8, 000
8. 000
4.000
11, 400
10,000
8,000
16, 000
8,000
25, 3448
0. 39
(0. 32
(0..16
0. 25
0. 32
0. 33
0.28
0. 5
O.Z
0.32
0.27
0. 24
3.04
4. 8
1.88
i. 84
4.6
4.7
2.73
3.9
1.2
3.91
2.82
2.45
1. 5
a.U1
3.91)2
2. 55
2.6
2.32
0.78
1.69
1.29
1.82
9, 12, Base OC
Noble OC
5, 8, 12, NobleOC
9, 13, Noble OC
9, Base OC
3
6
6
7, Noble OC
6
6
6
3
14, Noble OC
4, 10, Noble OC
6, Noble OC
5,11, 14,NobleOC
6, Noble OC
5, 12, Noble OC
1. Least-squares fit to 1972 test results converted to 1975 test procedure; slow choke
2. 1972 CVS-C test procedure
3. No high mileage data met standards
4. Emissions package incomplete/uncertain
5. Converter subsequently failed (within 4000 miles)
6. No high mileage data provided
7. Exceeded standards below 17,000 miles
8. Converter miles
9. Test continuing
10. Average of two tests
11. After maintenance
12. Standards were exceeded at lower mileage points
13. Best of two tests
14. Non-standard maintenance schedule
AI Air Injection
EFI Electronic Fuel Injection
EGR Exhaust Gas Recirculation
EM Engine Modifications
OC Oxidizing Catalyst
PTR - Partial Thermal Reactor
TR Thermal Reactor
-------
Two other high mileage vehicles may be noted. One of these is an
American Motors 1970 production model Hornet (same vehicle weight and
engine as the Javelin). This vehicle (Car DOO-24), equipped with an
Engelhard PTX 423 noble metal monolithic catalytic converter, has com-
pleted 50, 000 miles of durability testing and at this mileage a least squares
data fit indicates the emissions were 0.32, 4.8, and 2. 1 gm/mi for HC, CO,
and NO , respectively. The 1975 CO standard of 3. 4 gm/mi was exceeded
"
at roughly 30,000 miles. The other high mileage vehicle is a 400-CID
Chrysler car. This vehicle (Car 698), equipped with dual Engelhard
platinum/monolith converters which had been transferred from another
vehicle, developed a total converter mileage of 43,000 miles at emission
levels of 0. 16, 1. 88, and 3. 91 gm/mi for HC, CO, and NO , respectively.
The catalyst container failed mechanically at this point.
In addition to the two high mileage vehicles discussed above, the Volvo
first-choice emission vehicle might also be mentioned. This system accu-
mulated 25, 344 converter miles within standards. The catalyst failed
mechanically at 29, 900 miles.
Summarizing the emissions performance indicated by the data in Table 2-1,
eight first-choice systems have met the standards at accumulated mileages
in excess of 4000 miles. None of these has achieved the 50, 000-mile dur-
ability requirement; one system has met the standard at 32, 000 miles and
is st;ll under test. A total of three systems have demonstrated the potential
of achieving 25,000 converter miles within standards; two of the converters
subsequently failed in test. A total of three catalytic converter failures
occurred among the eight test vehicles which met the standards at more
than 4000 miles.
In the main, the alternate systems under investigation by the manufacturers
for'potential use in 1975 model year vehicles incorporate different types or
designs of catalytic converters but are otherwise similar to the emission
control packages selected as first-choice systems. A typical example is
2-6
-------
GM, whose second- and third-choice systems substitute noble metal pellet
and noble metal monolithic converter designs for the first-choice base metal
pellet converter design. Therefore, the discussion in the preceding para-
graphs, encompassing system descriptions, problems and plans for resolu-
tion, and fuel consumption and performance penalties, applies also to most
of the systems in the alternate systems category.
At least four manufacturers are experimenting with alternate 1975 emission
control systems which incorporate full-size thermal reactors. These
are Ford, GM, International Harvester, and Nissan. The Ford system is
installed on their Group II test fleet vehicles which are equipped with dual
(series) noble metal catalytic converters, a thermal reactor, and EGR. The
GM system consists of a thermal reactor with EGR. Durability data for ttiese
systems are not provided.. The International Harvester system exceeds the\
standards at zero mileage.
The Nissan system comprises engine modifications, a thermal reactor, EGR,
and an oxidizing catalytic converter. Problems encountered with the Nissan
reactor may be represented as being typical of thermal reactors. These
problems are reactor core deformation and durability, and the need to
develop inexpensive materials which will survive the high-temperature,
turbulent core environment. The fuel consumption penalty for the Nissan
system was quoted as 10 to 15 percent relative to 1972 model year vehicles.
The maximum mileage accumulated on this system was 32,000 miles at
emission levels ranging from 0.5 to 0.75 gm/mi HC, 11 to 13 gm/mi CO, and
0.75 to 1. 1 gm/mi NO . This system may be under development for 1976.
It may be noted that Toyota is testing a thermal reactor system which also
appears to be targeted to the 1976 model year. The system incorporates
engine modifications, EGR, an oxidizing catalyst, and a reducing catalyst.
The Toyo Kogyo thermal reactors are classified as first-choice devices.
2-7
-------
Two vehicles equipped with this system failed the CO standard before
8000 miles were accumulated.
2.2 SELECTED SYSTEMS --BY MANUFACTURER .
2.2.1 American Motors
2.2.1.1 First-Choice System
2.2.1.1.1 Special Design Features
American Motors first-choice 1975 system includes EGR, secondary air
injection, an oxidizing catalytic converter, and extensive engine modifica-
tions. A final decision has not been made as to whether the catalytic con-
verter will be a noble metal monolithic type or a base metal pelletized type.
Designs which appear to be prime candidates are the Engelhard noble metal
system and the AC-Delco base metal system. The engine modifications
include changes in the carburetion, induction system, valve timing,
cylinder head design, ignition system, and combustion chamber configuration.
2.2. 1. 1.2 Problem Areas and Plans for Resolution
The problems delineated by American Motors include the following:
a. Vehicles tested to date are far from satisfactory in terms
of driveability and freedom from stalling and rough opera-
tion during the first few miles after a cold start. American
Motors is attempting to resolve these problems by revising
the design of the fuel metering, induction, and ignition
systems.
b. Emission control durability is difficult to achieve. Although
American Motors has tested several vehicles to extended
durability mileage, none has met their engineering goals beyond
4000 miles. This is attributed to durability deficiencies in
both the catalyst and the engine (valve and ignition) systems.
c. Major underbody changes are required to permit packaging
the emission control system. American Motors states that
a minimum lead time of 2 years is needed to effect the neces-
sary body changes.
2-8
-------
2.2. 1. 1.3 Emissions
2.2.1.1.3.1 Test Programs and Vehicle Description
American Motors is currently testing several prototype emission control
systems installed in a broad spectrum of 6- and 8-cylinder engine/vehicle
combinations, both with and without EGR. The test fleet encompasses three
different 6-cylinder engine sizes (199, 232, 258 CID) mounted in two different
inertia weight vehicles (3000, 3500 Ib), and two V-8 engines (304, 360 CID)
mounted in 3500- and 4000-lb inertia weight vehicles.
2.2.1.1.3.2 Test Procedures
Durability vehicles were tested using the AMA driving cycle. Emission
testing employed both the 1972 CVS-C and the 1975 CVS-CH Federal Test
Procedures. All tests were conducted with fuel containing less than 0.024
gm/gal lead (0.014 gm/gal typical), less than 0.001 gm/gal phosphorous, and
less than 0.04 percent by weight sulphur.
Emission levels on Vehicle DOO-24 were obtained using the 1972 CVS-C test
procedure throughout the 50,000-mile durability test. At 50,000 miles, this
vehicle was also tested using the 1975 CVS-CH test procedure and the ratio
of CVS-CH to CVS-C emission levels determined. This ratio, defined by
American Motors as the correlation ratio, was then applied to the CVS-C test
points over the entire 50,000 mile range to arrive at the "calculated" CVS-CH
emission data presented in Figures 2-1, -2 and -3.
2.2.1.1.3.3 Emission Data Summary
Emission data reported by American Motors (Refs. 2-1 and 2-2) are pre-
sented in Tables 2-2 and 2-3 and Figures 2-1 through 2-12. The test vehicles
indicated are equipped with various emission control devices including
catalytic converters. With the exceptions noted in Table 2-2, all vehicles
are equipped with EGR; other equipment is not delineated except as noted.
None of the vehicles represents a complete 1975 prototype system.
2-9
-------
Table 2-2. Low Mileage Emission Data--
American Motors First-Choice System
Car No.
DZ7-1
D21-4
DOO-12
D08-6
Dll-2
Dll-3
Buck I
D14-2
Buck II
Buck III
D20-6
Buck IV
Inertia
Weight, Ib
3500
4000
3000
4000
4000
3500
3500
3000
3500
3500
3500
3500
Engine
360-V8
304-V8
199-6
360-V8
360-V8
258-6
304-V8
232-6
304-V8
304-vs
304-V8
304-V8
Test
Mileage
0
0
0
4000
0
0
0
0
0
0
0
0
Test
Procedure
1975 CVS-CH
1972 CVS-C
1972 CVS-C
1975 CVS-CH
1975 CVS-CH
1975 CVS-CH
1972 CVS-C
1975 CVS-CH
1972-CVS-C
1972 CVS-C
1975 CVS-CH
1972 CVS-C
Emissions, gm/mi
HC CO NO
X
0.50 5.01 3.24
1.02 23. 10 1.49(2)
0.29 6.26 2.38
0.39 2.50 -3.20(2)
0.39 6.09 2.83(2)
0.23 1.47 2.12(2)
0.30 4.73 -
0.23 2.38 3.28
0.37 4.53 -
0.44 5.07 -
0.25 2.03 1.95
0.75 5.78 -
Remarks
AC base metal pellet
(1)
(1)
Without EGR;2 UOP
miniverter
AC base metal pellet
AC base metal pellet
(1)
Without EGR; AC base
metal pellet
(1)
(1)
(1)
(1)
(1) Catalyst type and manufacturer not specified.
(2) Contradictory data, Refs. 2-3 and 2-4.
Table 2-3. High Mileage Emission Data --
American Motors First-Choice System
Car No.
D17-11
DOO-24
DOO-25
D01-28
Inertia
Weight, Ib
3000
3000
3000
4000
Engine
258-6
232-6
232-6
360-V8
Test
Mileage
32,000
50,000
24, 000
12,000
Test
Procedure
1975 CVS-CH
1975 CVS-CH
1975 CVS-CH
1975 CVS-CH
Emissions, gm/mi
HC CO NO
X
0.39 3.04 1.50
0.45 6.46 2.05(1)
0. 32 4. 80 2. lo'2>
0.75 8.57 2.75(3)
1.21 16.94 4. 33(4)
Remarks
AC base metal catalyst.
Test continuing
Engelhard noble metal
PTX-423 catalyst.
Test completed
Engelhard noble metal
PTX-423 catalyst.
Test terminated
AC base metal
catalyst. Test
continuing.
(1) Test points at 50,000 miles from Figures 2-1 through 2-3.
(2) Least squares straight line calculated values at 50,000 miles.
(3) Before maintenance.
(4) After maintenance.
2-10
-------
T I I
ENGINE at CID NO VAC. SPARK ADVANCE
CAR!. IV
TRAHSMSSION - AUTOMATIC
OOr - HORNET
CATALT1T - ENGELHARD tnoM* nwtal) PTX-421
rUCL - UNLEADED 10.0M vn/rill. PHOS. (<0.OOSI
TUT PROCEDURE II»TS <& ada*M from
IIT» prtotira)
CORRELATION DATIO Hfl IMBI8H * ° **"
COHIIELATION RATIO WAS DCTERUNED AT THE
50.000 mil. POINT MING DATA FHOU VEMCLC
OX.14. THIS RATIO WAS THEN APPLIED TO ALL
OTHER POINTS OF ACTUAL DATA GATHERED USING
THE I9T2 PROCEDURE. THE POINTS PLOTTED ON
21X000 30,000
DISTANCE. >
EMISSIONS
HC
w
M
S »
5
5 4
ENGINE - 232 CIO NO VAC. SPARK ADVANCE
CARS IV
TRAMSM&SKW - AUTOMATIC
BODY - HORNET
CATALYST - ENGELHARD (noM* rratal) PTX-423
FUEL - UNLEADED |f "
TEST PROCEDURE 111
1*72 proc**.r*|
~ CORRELATION RATIO [jfj ftlHIoll} c °'443
CORRELATION RATIO WAS DETERMINED AT THE
SO, 000 mil* POINT USING DATA FROM VEHICLE
000-24. THIS RATIO WAS THEN APPLIED TO ALL
OTHER POINTS OF ACTUAL DATA GATHERED USING
THE I9T2 PROCEDURE. THE POINTS PLOTTED ON
THIS PACE REFLECT THE USE OF 1 HE RATIO
s.-
CO
20, 000 30,000
OISTMCC. mi
.1
J 4
ENGINE - 232 CID HO VAC. SPARK ADVANCE
CARS. IV
TRANSMISSION - AUTOMATIC
BOOT - HORNET
CATALYST - ENGELHARD (ncbl* mnal) PTX-423
FUEL - UNLEADED 0.016 «n/0H|, PHOS. (<0.005)
TEST PROCEDURE M9tt W(M> oolcutn^ from
N72 proc»dur»I
'«
CORRELATE «T»
CHCMLUMNCSCENCC EQUIVALENT
CORRELATION RATIO WAS DC TERM NED AT THE
SO.000 mil* POINT USING DATA FROM VEHICLE
DOO-24. THIS RATIO WAS THEN APPLIED TO ALL
OTHER POINTS OF ACTUAL DATA GATHERED USING
THE t«72 PROCEDURE. THE POINTS PLOTTED ON
THIS PACC REFLECT THE USE OF THE RATIO
NO
20,000 30.000
DISTMCE. «i
Figures 2-1, 2-2, 2-3. American Motors Durability Test Data Vehicle DOO-24
2-11
-------
1"
CJ
1°.'
EMISSIONS
ENGINE IS* CID W/IOK ECU
EXHAUST DEVICE AC CAT CONV. IbM mMII
FUEL - UNLEADED IO.OM vn/fri|. PHO. I<0.009I. SULFUR
TUT PROCEDURE - 1»TS
COIII. COEFF. O.M2
ITO. ERKOR 0. U9
DET. FACTOR Ikr
HC
20,000 JO, 000
DISTANCE. !
ENGINE 2M CIO W/IOX ECU
EXHAUST DEVICE AC CAT. CONV. (MM mMill
TEST PROCEDURE - I9TS
STD. tKKOK O.UT m/M
DET. FACTOR (by Isolation) 1. OS
FUEL: /9n'
UNLEADED 0. 016 gm/J.1 /
PHOS. I
-------
EMISSIONS
0.1
I
0.2 -
.L=
CATALYST - CNCELHAMD PTX-4Z3 |ne*ta mrall
IS* *&&&?."& "**> ""* l<°-"»1
HC
10,000 10.000
OISTIICE, !
(HUM 212 CIO
CAR*. IV
TMANM1UICM - AUTOMATIC
COT - HOKNET
CATALTIT - ENOELHAUD PTI-421 |noM« mMII
FU(L - UNLEADED JO. OH |m/g*l|.
PHO9. (Ml Mn 0.0051,
- PIlOCEOr
TEST
I
EDU*E I
I
I
CO
10.000 30,000
DISUICE, ml
ENGINE 232 CID
CADI. IV
TRANSUSSIOH - AUTOMATIC
MOOT - HOMNET
CATALYST - EHBELHAIID PTX-42] |noM> imMI
FUEL - UNLtAOEO 10.014 frJfH. PMOJ. I<0.b03l
TEST PDOCEOUIE - l*n
OET. FACTOR - O.M (by Mnpotatlail
r
-I__L° ZIL
i m.
NO,
20.000
OISTIICC.
Figures 2-7, 2-8, 2-9. American Motors Durability Test DataVehicle DOO-25
2-13
-------
EMISSIONS
0.4
0.1
ENOINE S40 CIO
CARB. 4V
TMKSMUIOM AUTOMATIC
CATALYST -
HC
MI ooo to.no
DUKRCl. ml
90,000
I 20
s
tf»
ENGINE MO CIO
CARB. 4V
TRANSMISSION - AUTOMATIC
OOY - HORNET
CATALYST * AC lbo» imMt)
FUEL - UNLCADCD O.OU gm/gal.
PHtB. < 0.009
TE9T PKOCtOUHE - I9R
CO
M. 000 10,000
OIS!«»Ct. HI
CNCINC . MO CID
CARS. 4V
TRANSMISSION - AUTOMATIC
BOOT - HORNET
NO,
20,000 )0,000
DISTMCE ,«l
Figures 2-10, 2-11, 2-12. American Motors Durability Test Data Vehicle D01-28R
2-14
-------
High mileage emission data are presented in Figures 2-1 through 2-12. The
data are summarized in Table 2-3 which shows emission results at the highest
mileage accumulated on each vehicle.
Referring to the high mileage emission results, there are two vehicles of
particular interest on the basis of performance. These are Vehicles DOO-24
and D 17-11. Vehicle DOO-24 is a 1970 production model 258-CID 6-cylinder
Hornet equipped with EGR, secondary air, and an Engelhard noble metal
(PTX 423) monolithic catalytic converter. The vehicle inertia weight is
3000 Ib. This vehicle has completed the 50,000-mile durability test with both
the HC and NO emission levels below the 1975 standards based upon the
least squares fit to the emission test results shown in Figures 2-lthrough 2-3.
The CO straight line value at 50,000 miles exceeded the standard by a factor
of approximately 40 percent.
The other vehicle of interest is D17-11 which to date has accumulated 32,000
miles, with all emission levels below the 1975 standards. This vehicle is a
258-CID 6-cylinder Javelin equipped with EGR (10 percent), secondary air,
and an AC-Delco base metal pelletized catalyst. The vehicle inertia weight
is 3000 Ib. Emission results achieved through 32,000 miles are shown in
Figures 2-4 through 2-7. Durability testing of this vehicle is continuing.
Two additional vehicles are undergoing EPA durability testing at American
Motors. These are vehicles DOO-25 and D01-28R. Vehicle DOO-25 is a
232-CID 6-cylinder Hornet equipped with EGR, secondary air, and an
Engelhard PTX-423 catalytic converter. The vehicle inertia weight is 3000 Ib.
American Motors states (Ref. 2-3) that this test was terminated at 20,000
miles because of high deterioration rates. However, the test mileage data
submitted in Ref. 2-3 indicates an additional test point at 28,000 miles as
shown in Figures 2-7 through 2-9. At the 24, 000 mile test point, both the
HC and CO emission levels were significantly higher than the 1975 standards.
2-15
-------
Vehicle D01-28R is a 360-CID V-8 Hornet equipped with EGR, secondary
air, and an AC-Delco base metal catalytic converter. The vehicle inertia
weight is 4000 Ib. Emission results achieved through 12,000 miles are
shown in Figures 2-10 through 2-12. Poor emission control has been
exhibited on this vehicle, with CO and NO exceeding the 1975 standards
from 0 miles and HC from 4000 miles. Extremely rapid deterio.ration of
the catalyst efficiency is also indicated by both the HC and CO data.
2.2.1.1.3.4 Best Emission Results
The best low and high mileage emission results reported to date by American
Motors (Ref. 2-4) are shown below in Table 2-4. It is of interest to note that
in each case this was achieved with the 258-CID 6-cylinder engine mounted
in the 3000- and 3500-lb inertia weight vehicles. Also shown in Table 2-4
are the American Motors engineering goals at 0 and 4000 miles. It will be
noted that Vehicle Dll-3 meets Lhe CO and NO engineering goals at 0 miles
but exceeds the HC goals at both 0 and 4000 miles.
Table 2-4. Best Emission Results -- American Motors
Item
Best High Mileage
Best Low Mileage
Engineering Goals
at 0 miles
at 4000 miles
Vehicle
D17-11
Dll-3
Engine
258-6
258-6
Miles
(1)
32,000
0
HC
0.39
0.23
0. 10
0. 15
CO
3.04
1.47
1.50
2.55
NO
1.50
2. 12
2.2
2.2
(1) Standards were exceeded at several mileage test points below 32, 000
miles.
2.2.1.1.3.5 Test Data Variability
Test data variability as reported by American Motors (Ref. 2-4) for seven
6- and 8-cylinder low mileage vehicles has been utilized to calculate the
coefficient of variation (tr/x, %) for consecutive CVS-CH tests, where
-------
Table 2-5. Range of Test Data Variability
for American Motors Low
Mileage Vehicles
(Coefficient of Variation, tr/x.%)
HC 6 - 21%
CO 11-21%
NO 1 - 10%
?c
2.2.1.1.4 Fuel Consumption and Performance Penalties
Fuel consumption penalties associated with 1975 model year vehicles were
not discussed in detail by American Motors beyond a. statement estimating
that the fuel consumption would increase by 8 to 18 percent over the 1972
vehicles (Ref. 2-4). Those portions of the 1975 emission control system
which would contribute to this increase in fuel consumption were not
discussed.
Specific reductions in performance were not presented by American Motors
other than to delineate it as one of the major unresolved problem areas
associated with the catalyst-EGR system being developed to meet the 1975
standards. General driveability was described as far from satisfactory
(Ref. 2-4), as was freedom from stalling and rough operation during the first
few miles after a cold start.
2.2.1.2 Alternate Systems
American Motors does not have an alternate 1975 system. They believe
their first-choice system is the only approach which has any chance for
success and that exploring alternative or second-choice systems would dilute
their primary effort (Ref. 2-4).
2-17
-------
2.2.2 Chrysler
2.2.2.1 First-Choice Systems
2.2.2. 1. 1 Special Design Features
Chrysler's first-choice 1975 emission control system incorporates the
following devices and modifications (Ref. 2-5, -6, -7):
Catalytic converter (platinum/monolith)
Exhaust gas recirculation (EGR)
Exhaust port air injection
Catalyst by-pass protection system
Partial exhaust thermal reactor
Engine modifications
Double wall exhaust pipe
Heated carbureter air intake
Carburetor mixture calibration with barometric pressure
control and electric assisted choke.
Electronic engine control
Chrysler's reasons for selecting this system maybe summarized as f ollows.
The selection of the catalytic converter was based on the success achieved
with this device in meeting the 1975 standards under zero-mileage laboratory
conditions. The monolithic noble metal converter design was preferentially
selected over pelletized systems on the basis of Chrysler's experience that
the noble monolith had higher activity at the lower engine temperatures .
Also, Chrysler's early development work with pebble-bed catalysts showed
pronounced deterioration problems. The converter utilizes a monolith
ceramic substrate coated with an Engelhard platinum catalyst-encased in a
304 stainless steel container. The device is positioned close to the engine in
the toeboard location, based on the need for fast warmup and adequate operat-
ing temperatures as well as the availability of space.
2-18
-------
The exhaust thermal reactor and the auxiliary air supplied to the exhaust
ports is employed to burn a major portion of the combustibles in the exhaust
during cold start and warmup and to increase catalyst temperature to an
effective operating level. EGR is employed to provide NO control. Sub-
stantial development of the EGR system is proceeding to provide flow control
and durability of all components involved. The double wall exhaust pipe
minimizes heat loss between the thermal reactor and the catalytic converter.
It thus helps in achieving a faster warmup of the catalyst to "light-off"
temperature.
Chrysler states that any temperature in excess of 1500 F can seriously
damage the effectiveness of the catalyst; therefore, a by-pass protection
against high exhaust gas temperatures is provided to route the exhaust gas
around the converter whenever the limiting temperature is exceeded.
2.2.2.1.2 Problem Areas and Plans for Resolution
Chrysler reports that while they have made encouraging progress to date, a
number of difficult problems remain to be resolved. The most pressing of
these are:
Material durability at high temperature
Vehicle driveability
50,000-mile durability of system components
Maintenance of emission levels for 50,000 miles
Fuel penalties
Reducing system cost
Chrysler's goal is to optimize the system as a whole to achieve the lowest
possible emission levels consistent with safe, dependable performance. The
fuel penalties are brought about by vehicles made heavier by the added safety
and emission control systems, decreased compression ratios, ignition spark
timing changes to achieve maximum emission control, EGR which requires
richer air/fuel ratios to retain acceptable and safe driveability, and by
increased exhaust backpressure.
2-19
-------
Durability of the subsystems is an area of great concern to Chrysler.
Catastrophic failure of the catalyst container has occurred, produced by such
events as ignition system failure under cruise conditions. A catalyst by-pass
jX.
and actuator device has been under development, but its success depends on
the development of a reliable sensor system. The location of the sensor is
very critical since any delay can result in temporary overtemperature condi-
tions. Low temperature switch settings can result in loss of emission control
at steady-state operating conditions. Lack of suitable sensors with adequate
response characteristics is delaying meaningful durability evaluations.
Although platinum monolith catalysts continue to be favored for emission
effectiveness and durability, recent progress reported by catalyst manu-
facturers with improved pebble catalysts is prompting Chrysler to re-evaluate
this type of system.
2.2.2.1.3 Emissions
2.2.2.1.3.1 Test Programs and Vehicle Descriptions
A fleet of eight 1973 Plymouth Furys are being used for "development testing
of the first-choice emission control system. This program has the code name
A-335 and was initiated in April 1971. The eight cars are equipped with a
360 CID V-8 engine, automatic transmission, power steering and brakes,
and air conditioning.
A schematic of the vehicle emissions package is provided in Figure 2-13.
Supplementary information on emission system components is being obtained
from research vehicles other than those in this eight vehicle test fleet. For
example, Chrysler Vehicle #333 (see Table 2-6) has provided considerable
information pertaining to catalyst durability. Other vehicles have been used
to establish the performance of the emission control package with different
engine sizes.
2-20
-------
N
tx)
ELECTRIC
CHOKE
MODIFIED
FRAME RAIL
ALTITUDE
COMPENSATING
CARBURETOR
MONOLITHIC CATALYST
CONVERTER
CATALYST
BYPASS VALVE
EXHAUST MANIFOLD
REACTORS
AIR PUMP
EXHAUST
GAS RECIRCULATION
ELECTRONIC
ENGINE
CONTROL
BY-PASS PIPE STANDARD MUFFLER
Figure 2-13. Chrysler A-335 Special Emission Car (System Features)
-------
2.2.2.1.3.2 Test Procedures
A major portion of vehicle test work is carried out at the Chrysler Proving
Ground in Chelsea, Michigan. This facility is used to test the emissions
control systems under a variety of operating conditions. Also conducted at
this location are the official certification activities and mileage accumulation
tests. A modified AMA schedule is generally used for mileage accumulation:
however, certain of the Chrysler durability vehicles were run on driving
schedules which were considerably milder than the modified AMA cycle.
Chrysler has used four different emission test procedures:
1975-CVS-CH 1975 Federal Test Procedure
(three bag cold/hot start
technique).
1972-CVS-C 1972 Federal Test Procedure
(one bag cold start technique).
1972-CVS-H Same as 1972 CVS-C except the
car does not have a cold soak and
is started in a warmed up
condition.
Hot 7-mode One hot cycle of the 1971 Federal
Test Procedure.
Most tests are being made with fuel containing 0.02 - 0.03 gm/gal of lead.
Chrysler believes that the catalyst durability might be cut in half using the
proposed Federal lead level of 0.05 gm/gal (max).
2.2.2. 1.3.3 Emission Data Summary
Chrysler's emissions results are presented in Tables 2-6 and 2-7. Low
mileage emission results are shown in Table 2-6. The cars listed have been
used not only to test the effectiveness of the first -choice subsystems but also
to test the effects of such engine adjustments as spark advance and EGR
flow rates. Two mileages are shown: one is representative of the accumu-
lated mileage on the defined system, the other is the total accumulated
mileage on the particular catalytic converter configuration being tested.
2-22
-------
Table 2-6. Chrysler Low Mileage Emissions
to
i
tv
Car No.
1 19
134
145
258
Engine CID
440
360
318
360
Mileage
Vehicle
396
671
1038
1268
157
183
265
431
913
987
1205
1489
1783
1969
2021
10
47
331
10
247
255
332
514
627
Catalyst
396
671
1038
1268
157
183
265
431
913
987
1205
1489
1783
1969
2021
0
37
321
0
237
245
322
504
617
Emissions,gm/mi
HC CO NOX
0.39 2.8 2.85
0.26 0.7 1.51
0. 13 1. 3 1.85
0.23 1.0 1.28
0.28 8.4 2.26
0. 15 3.4 2.25
0.22 4.9 1.66
0.29 4.3 1.54
0.20 1.5 1.78
0.45 9.8 2.09
0.21 7.2 1.14
0.17 2.0 2.28
0.40 5.9 2.24
0.20 0.6 1.90
0.21 0.3 1.84
1. 66 15. 0 2. 17
0.37 5.6 3.05
0.29 4.7 2.42
0.22 2.6. 1.54
0.39 1.4 2.92
0.02 0.1 2.95
1.49 5.7 4.52
0.21 1.0 3.70
0.23 0.9 5.44
Test
Procedures
1975-CVS-CH
1972-CVS-C
1975-CVS-CH
1975-CVS-CH
1972-CVS-C
1972-CVS-C
1972-CVS-H
1972-CVS-C
1975-CVS-CH
Converter or
Thermal Reactor (TR)
Engelhard Vert/Oval,
135 in3 (.2% Pt).
No TR
EngeLhard Toeboard,
90 in3 (.2% Pt).
No TR
Engelhard Oval-
Underseat. No TR
Engelhard Toeboard
(.35% Pt). No TR
Thermal reactor
Remarks
Air Pump 1. 25:1
Air Pump 1. 67:1
Choke mod: leaner A/F
Choke mod; high- flow
EGR valve
Air pump 1. 34:1
EGR on at coolant above
120°
Richer idle set
Air pump 1. 52: 1
A/F = 0. 064 (richer main
jet)
A/F = 0.072
New carburetor
High-flow EGR valve
New intake system;
large Venturi 4 bbl carb.
Larger Venturi thermo
quad.
Very rich choke
Repaired choke diaphragm
Air pump 1. 67: 1
Richer idle set
No EGR
Rerunning baseline
configuration
-------
Table 2-6. Chrysler Low Mileage Emissions (Cont. )
ro
Car No.
378
303*
306*
326
333
Engine CID
360
360
360
400-2V
360
Mileage
Vehicle
15
112
415
870
1238
1340
1446
370
728
998
1244
1334
624
1069
143
621
819
1058
1201
1300**
0
2107
Catalyst
0
97
400
855
1225
1325
1431
370
728
998
1244
1334
624
1069
143
621
819
1058
1201
1300**
0
2107
Emissions, gm/mi
HC CO NOX
0.22 3.3 2.3
0.32 5.6 1.54
0.06 0.6 2.81
0.17 2.2 3.26
0.21 3.6 4.85
0.43 4.1 3.91
0.14 1.2 3.69
0.37 6.7 1.79
0.50 3.4 1.83
0.12 3.9 1.55
0.46 3.4 1.70
0.46 14.5 1.55
0.24 2.2 6.69
0.38 4.3 5.31
0.72 6.2 4.53
0.52 3.1 3.63
0.57 4.8 2.52
0.36 3.9 1.87
0.48 2.3 2.40
0.30 1.2 4.00
0.41 2.48 1.49
0.38 2.37 1.45
Test
Procedures
1972-CVS-C
1975-CVS-CH
1972-CVS-C
1972-CVS-C
1975-CVS-CH
1972-CVS-C
Converter or
Thermal Reactor (TR)
Engelhard. PTR
Engelhard Oval
(0.2% Pt). PTR
Engelhard Oval
(0.2% Pt). TR
Engelhard Vert
Oval (0.27. Pt).
No TR
Twin Engelhard
Toeboard (0.2% Pt).
No TR
Remarks
Double wall exhaust
pipe
Auto spark advance
control (OSAC)
Standard exhaust
pipe
New carburetor;
double wall exhaust
pipe
Air pump 1. 34:1;
cast reactors
Tuneup, oil change
High- flow EGR
valve
Carburetor and EGR
valve mod
Baseline plus man-
flow EGR valve
Air pump l.B34:I;
cast reactors
New Carburetor
EGR above 115° F
water temp. Air pump
1.67:1
Carburetor mod
Tuneup and choke mod
Carburetor mod
Carburetor mod
Air pump 1. 7:1
-------
Table 2-6. Chrysler Low Mileage Emissions (Cont. )
ro
ro
un
Car No.
385
467*
467*
499*
585
650
683
Engine CID
360-2V
360
360
360
440
400
360
Mileage i Emissions, gm/mi Test
Vehicle
0
2000
96
189
215
4718
4889
107
0
35=5
3749
0
1000
3000
3000
0
3022
Catalyst
0
2000
96
189
215
0
171
107
0
359
3749
0
1000
3000
3000
0
3022
HC CO NO j Procedures
0.28 4. 3 2. 19
0.04 1.5 1.90
0.08 8.0 1.50
0.06 1.9 1.60
0. 24 4. 3 2.10
0.34 23.9 5.64
0. 12 6. 5 1.43
0.2 3.3 2.19
0, 73 2. ? 2.4!
0. 16 2. o 2. 07
0. 30 3. 7 1. 69
0. 12 1.51 -
0. 14 3. 65
0.47 2.2 1.75
0.75 1.44 5.03
0.03 3.80 3. SI
0.05 2.50 2.93
1972-CVS-C
1972-CVS-H
1972-CVS-C
197S-CVS-CH
1
1975-CVS-CH
1975-CVS-CH
1972-CVS-H
Hot 7 mode
1972-CVS-H
1972-CVS-C
1~'72-CVS-C
Converter or
Thermal Reactor (TR)
Engelhard Toeboard
(0. 35% Pt). No TR
Engelhard Oval
135 in3 (0.2% Pt).
PTR
New Englehard
converter (C. 2% Pt)
135 in3
Engelhard Horiz Oval
135 in3 0.2% Ptl.PTR
Engelhard Toeboard
Vert Oval 135 in3
(0. 2 To Pt). No TR
Dual Engelhard
Toeboard 107 in3
(0.2% Pt). 2-4
containers. No TR
Engelhard Vert Oval,
135 in (0.2% Pt).
No TR
Remarks
Air pump 1. 526:1
A/F changed
Air pump 1 . 52 : 1
Ne\v carburetor
New engine
Air pump 1. 52:1
Air pump 1. 25:1
Air pump 1 . 25:1
OSAC
Air pump 1. 52:1
i
A-335 program vehicle Mileage estimated
-------
Table 2-7. Chrysler High Mileage Emissions
Car No.
333
385
535
650
698
683
CID
360
Mileage
Vehicle
0
Catalyst
0
5030 5030
10121
10121
10318 ' 10318
i
360-2V
440
15117 | 15117
20327
20599
25336
32952
35712
35943
36094
0
5000
10000
15000
20000
257
3749
8462
13678
18330
! 21443
400
360
3000
8000
0
10000
20000
25000
30000
0
20327
20599
25336
32952
35712
35943
36094
0
5000
10000
15000
20000
257
3749
8462
13678
18330
21443
3000
8000
13000
23000
33000
38000
43000
0
I
3022 j 3022
8350 ' 8350
13284
13284
Emissions, gm/mi
HC CO N0x Test Procedure
0.41 2.48 1.49
0.62 5.41 1.72
0.40 4.1 1.54
0.32 2.2 1.52
0.38 3.9 2.25 j
1.1 11. 5 2. 76 1
1
0.73 5.4 2.51
0.45 6.0 3.20
0.42 5.3 2.72
0.21 4.5 1.43
0.36 4.7 0.78
0.33 4.1 1.56 i
0.28 4. 3 2. 19
0.26 6.8 1.30
0.47 2.0 1.15
0.28 2.38 1.55
0.26 2.84 1.56
0.20 2.4 2.46
0.30 3.7 1.69
0.35 2.6 1.55
0.44 2.1 1.5
0.39 1.9 1.10
.
0.75 1.44 5.03
0.04 12.7 4.73
0.11 3.9 1.84
0.39 1.7 2.55
0.53 2.19 4.30
0. 22 3.99 3.99
0.16 1.88 3.91
0.03 3.80 3.81
0.05 2.5 2.93
0.11 6.74 3.07
0.07 4.25 2.69
1972-CVS-C
1972-CVS-C
Thermal Reactor (TR)
Twin Engelhard Toeboard (0.2% Pt).
No TR
Engelhard Toeboard (0. 35% Pt)
(Improved catalyst, no TR)
Engelhard Toeboard Vert Oval
135 in3 (0.2% Pt). No TR
!
1975-QVS-CH
1972-CVS-H
1972-CVS-C
1972-CVS-C
Dual Engelhard PTX-423S
107 in3 Toeboard. No TR
Dual Engelhard PTX-423S
107 in3 Toeboard. No TR
Engelhard Vert Oval 135 in
Remarks
Air pump 1. 7:1
Catalyst temperature kept
below 1500 F
EGR mods, engine
tune -up
New air pump
Replace choke spring
Replace monolith wrapping
Still running
Air pump 1. 526:1
Catalyst container failed at
23,000 mi.
Air pump 1. 52:1
1
General endurance test
Catalyst failed
Air pump 1. 25:1
System transferred from
Car 650: General endurance
test; no Pb, no P in fuel
New Engine
Converter damaged
Air pump 1. 52:1
(0.2% Pt). No TR
General endurance test
Still running
ro
i
N)
-------
Reported high mileage emissions are listed in Table 2-7. Good emission
results were obtained with Vehicle 333 using a twin configuration Engelhard
converter (0.2 percent platinum on a spiral monolith substrate) in a toeboard
location. Vehicle 333 was driven on an AMA schedule modified so that the
catalyst temperature never exceeded 1500 F. This car was frequently tuned
up and parts replaced.
Vehicle 385 had an improved catalyst with higher platinum loading. However
it was driven on the Chrysler proving ground (a more severe test than that
above) and received only the customer-specified servicing. This catalyst
failed at 20, 000 miles. The failure was caused by abrasion of the catalyst;
container on the roadway. A similar test will be conducted in the near future
using a stacked monolith substrate.
2.2.2.1.3.4 Best Emission Results
Several of the tests showed emission levels within the 1975 standards. Three
first-choice-type systems have met the standards at high mileage.
The best low mileage emission results were obtained with Vehicle 119
3
(Model HP85, 440-CID engine with automatic transmission). A 135 in
Engelhard vertical oval converter was used. Emissions at 1268 miles were
0.23, 1.0, and 1.28 gm/mi HC, CO, and NO , respectively.
3C
The best high mileage emission results were obtained with Vehicle 385
(360-2V engine with automatic transmission). This car was driven on the
regular Chrysler proving ground and did not receive special servicing. The
converter was an Engelhard 0.35 percent platinum monolith in a toeboard
location. At 20,000 miles, the emission levels were well within 1975
standards at 0.26, 2.84 and 1. 56 gm/mi HC, CO, and NO , respectively.
Jt
However the catalyst container failed at 23, 000 miles.
Two systems have done well in Chrysler's durability testing. One of these,
Vehicle 333 (Plymouth Fury, 360 CID) utilized a converter designated by
Chrysler as "twin Engelhard toeboard converters" (0.2 percent platinum/
monolith). Mileage accumulation was accomplished using the AMA driving
cycle modified to lower acceleration rates above 50 mph to hold the catalyst
2-27
-------
bed temperature below 1500 F. The car was tuned up every 5000 miles. At
36,094 miles the emission levels per the 1972-CVS-C procedure were 0.33,
4.1, 1. 56 gm/mi for HC, CO, and NO , respectively. At this point it was
'^
noted that the monolith was loose in its container and was abrading. The other
system that performed well was run on Vehicles 650 and 698 (400 CID engine)
and utilized a converter designated by Chrysler as a "dual Engelhard toeboard
107 in converter" (0.2 percent platinum/monolith). This system accumulated
43,000 miles before a hole was burned in the side of one of the containers.
Per the 1972-CVS-C procedure, the emissions were 0.16, 1.88, 3.91 gm/mi
for HC, CO, and NO , respectively.
2.2.2.1.3.5 Test Data Variability
Chrysler reports that identical repeated 1975 CVS-CH tests within the same
laboratory produce results that vary by about plus or minus 25 percent.
Between laboratories, the variation is well over plus or minus 50 percent.
Calculations made on a limited sample of data taken from Vehicle 333 show
that three repeated tests in the same facility produce the following standard
deviations (in percent):
HC = ±28.8, CO = ±48.6, NO = ±12.3
2.2.2.1.4 Fuel Consumption and Performance Penalties
Chrysler reports that, depending on the speed,'the 1975 first-choice system
wquld have a fuel economy of 1 to 4 mi/gal less than the 1971 system. It is
also reported that in city traffic the fuel economy for the 1975 model will be
81 percent of 1968 model year values.
Chrysler states that to avoid stumbles, stalls, and inadequate acceleration,
engines with larger displacement, richer air/fuel ratios, and faster idling
speeds will have to be used. It is probable that the smaller engines in some
models will have to be discontinued in order to retain acceptable and safe
2-28
-------
drive ability. The expected performance penalty is not explicitly stated in
Chrysler's submittal.
2.2.2.2 Alternate Systems
2.2.2.2.1 Special Design Features
Several modifications to the Chrysler first-choice system are being pursued.
As of April 20, 1972 the final selection of the catalyst to be used in production
had not been made; a number of different catalytic converter systems are
currently being evaluated for possible use. The second-choice system seems
to center around the use of a pellet-type converter such as the UOP stabilized
spherical platinum (PTAS) catalyst. Other possible modifications to the first-
choice system include (1) deletion of the 30 percent thermal reactor and of the
double wall exhaust pipe (provided that cold start emissions can be brought
within manageable limits), and (2) elimination of the catalyst by-pass system
(provided that better exhaust gas temperature control is achieved or more
tolerant catalysts are found).
2.2.2.2.2 Problem Areas and Plans for Resolution
In the past, unacceptable deterioration observed in testing pebble catalytic
converters led to a decision by Chrysler to shelve these devices in favor of
the noble metal monolith catalytic converter. However, recently reported
advances in the technology has prompted Chrysler to re-examine the whole
class of pebble-type catalysts. Chrysler plans to resume testing of the pellet
systems using the performance achieved with the Engelhard PTX platinum/
monolith converter as a reference for comparison. It is believed that the
high temperature stability of catalysts such as UOP PX-4 might provide the
basis for eliminating the 30 percent thermal reactor and the catalyst by-pass
from the list of subsystems to be used on the 1975 model.
2.2.2.2.3 Emissions
The more advanced pebble-bed catalysts such as the UOP-PTAS type have
not yet been tested. Emission levels obtained with some of the early pellet-
type catalysts tested by Chrysler are shown in Table 2-8.
2-29
-------
Table 2-8. Chrysler Low Mileage Emissions (Alternate
Catalytic Converter Design)
Car No.
258
259
259
259
Engine
CID
360
360
360
360
Mileage
0
141
0
27
0
50
0
170
496
519
857
Emissions, gm/mi
HC CO NOx
0.66 4.1 5.93
0.66 4.8 5.29
0.30 4.5 1.39
0.34 3.5 1.34
0.04 0. 9 1. 15
0.25 5.6 2.06
0.23 3.6 1.21
0.17 3.6 1.83
0.40 3.1 1.41
0.47 2.9 1.33
1.62 39.4 0.41
Test
Procedure
1975-CVS-CH
1972-CVS-C
1972-CVS-C
1972-CVS-C
1975-CVS-CH
Converter or
Thermal Reactor (TR)
Davex 45-V toeboard
pebble bed, PTR
Monsanto EGA 302
pebble bed, PTR
Davex 137 pebble bed,
PTR
Houdry 1057 JX8-2X1
pebble bed, PTR
Remarks
-
Secondary air
mod
Air pump 1. 52: 1
New air pump;
A/F change
I
W
o
-------
2.2.3 Ford
2.2.3.1 First-Choice Systems
2.2.3.1.1 Special Design Features
Based upon currently available data, it is Ford's judgment that its first-
choice system for 1975 will consist of a single catalytic converter in con-
junction with EGR, secondary air injection, and engine modifications. A
single Engelhard PTX noble metal monolithic catalyst will be used on the
4-cylinder and 6-cylinder passenger cars and the V-8 F-100 pickup truck.
Two catalysts, one on either side, will be used on the V-8 engine passenger
cars.
This system is favored because the projected 50,000-mile emission per-
formance levels closely approximate the catalyst-thermal reactor system at
a substantially lower cost to the consumer. This projected cost differential
to the customer has been estimated by Ford to be $140 (Ref. 2-8).
2.2.3.1.2 Problem Areas and Plans for Resolution
A major problem area reported by Ford (Ref. 2-9) is the deterioration of
catalyst efficiency. No car that Ford has tested has successfully accumu-
lated 50,000 miles and maintained the emission levels within the 1975
standards. A 32-car test program was started in March 1972 at Riverside
as part of the effort to evaluate the performance of the catalyst and the
emission control system as a whole.
2.2.3.1.3 Emissions
2.2.3. 1.3. 1 Test Programs and Vehicle Description
The current Ford test program is a two-phase program utilizing 44 vehicles:
32 vehicles are being tested at Riverside, California and 12 vehicles at
Dearborn, Michigan. Phase I is a 50,000-mile durability study to determine
the system/component deterioration factors. Phase n is being conducted to
determine 4,000-mile emission levels which, in conjunction with the
2-31
-------
deterioration factors determined from Phase I, can be used to project
certification emission capabilities of the candidate systems.
Four groups of vehicles will be tested in Phase I at Riverside. Each group
of vehicles will consist of:
Two 460-CID Lincolns
Two 351C-CID Galaxies
Two 250-CID Mavericks (6 cylinder)
Two 360-CID F-100 pickup trucks
The Phase II tests to be conducted at Dearborn will consist of three of each
of the above vehicles.
Current production 1972 vehicles will be modified for the Phase I and II test
programs to include the appropriate exhaust system, heat shields, etc. , for
use with reactor manifolds and/or catalytic converters and will be equipped
\
as follows:
Secondary air injection
Induction-hardened valve seats
Breakerless ignition
Advanced carburetors and distributors
Exhaust gas recirculation
Group I vehicles will be fitted with a single PTX noble metal monolithic
catalyst on the 6-cylinder Mavericks and the F-100 pickup trucks. Two PTX
monolithic catalysts will be fitted, one on each side, to the Galaxies and
Lincolns. Group II vehicles will have a manifold reactor plus a second single
PTX catalyst in series with the converter configuration used on Group I
vehicles. Group III vehicles will consist of the dual (series) catalytic con-
verters without the thermal reactors. A decision on the components to be
used on Group IV vehicles is scheduled for late April 1972 and will be based
on an analysis of the results from Groups I through III to that date.
2-32
-------
2.2.3.1.3.2 Test Procedures
The vehicles at Riverside are being tested in accordance with the AMA
durability cycle. Emission test results are based on the 1975 CVS-CH test
procedure. In addition to the Riverside data, low mileage emission results
(CVS-CH) were also reported for a Mercury Marquis equipped with the
catalyst-only system. The driving cycle and vehicle mileage were not
specified for the Mercury.
2.2.3.1.3.3 Emission Data Summary
The low mileage emission data reported by Ford for the catalyst-only equipped
vehicles for both the Riverside and Dearborn.fleets are presented in Table
2-9. The data shown for the Riverside vehicles are the average of two con-
secutive tests for each vehicle at each of the reported mileage points. It
should be noted that of the Riverside vehicles, the Mavericks exceeded the
1975 standards for HC and NO " at 2000-4000 miles, and the Lincolns exceeded
X
the 1975 standard for HC at 0 miles and that for CO at 2,000 miles. The
F-100 exceeded the 1975 standards for HC and CO at 0 miles but the data indi-
cate a gradual reduction in HC and CO and at 4, 000 miles the standards are
met. The reasons for this were not clear to Ford (Ref. 2-9), but may be a
"green" engine effect.
The Dearborn Test Fleet data, also shown in Table 2-9, include the results
of two consecutive tests at each test mileage for each vehicle. The Dearborn
cars were reported as being equipped with catalysts similar to the Group I
vehicles at Riverside. Ford also reported (Ref. 2-10) that the Dearborn
vehicles "have higher CO levels than the durability cars running at Riverside
because of an effort to reduce NO emissions to levels somewhat more
X
typical of what would be required for a 1975 model. " No additional informa-
tion was provided by Ford, although the fact that, in general, the Dearborn
cars exhibit lower NO and higher HC/CO emissions than the Riverside fleet
X
would suggest that a lower air/fuel ratio setting and/or a higher EGR rate was
used on the Dearborn fleet.
2-33
-------
Table 2-9. Low Mileage Emission Results--Ford
(Group I) First-Choice System
Vehicle
Riverside Test Fleet^ '
Maverick #1
Maverick #2
Ford #1
Ford #2
F-100 #1
F-100#2
Lincoln #1
Lincoln #2
Development Vehicle
Mercury
Engine CID
250
250
351
351
360
360
460
460
429
Mileage
. '.
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
***
Emissions, gm/rrii*
HC CO NO
X
0.41 2.23 2.45
. 0. 58 3.28 2.96
0.63 3.56 3.48
0.32 0.95 2.92
0.35 1.37 4.20
0.42 3.19 3.04
0.19 1.91 2.34
0.43 3.17 2.47
0.25 1.91 2. 56
0.20 1. 75 2.46
. 0.22 2.32 2.75
0.32 2.29 2.89
0.55 4.42 2.30
0.47 3.82 2.55
0.38 4.40 2.47
0.49 2.83 2.45
0. 36 2.41 2. 81
0.33 2.11 2.74
0.63 3.21 2.36
0.54 3.52 2.25
0. 60 3.21 2. 35
0.43 2.88 2. 16
0. 54 3. 39 2. 31
0.70 4.43 2.51
0.23 1.03 1.14
^CVS-CH test procedure
Average of two consecutive tests at each mileage point
Reported only as "low mileage"
2-34
-------
Table 2-9. Low Mileage Emission Results --Ford (Group I)
First-Choice System (continued)
Vehicle
<-*' -',-
Dearborn Test Fleet
Maverick
Ford
F-100
Lincoln
Engine CID
250
351
360
460
Mileage
0
4000
0
4000
0
0
4000
o..
'*'"'
Emissions, gm/mi
HC CO NO
X
0.52 6.56 1.51
0.29 5.69 1.54
0.54 5.68 1.76
0.72 7.05 2.10
0.22 2.31 1.86
0.25 3.18 1.88
0.35 5.77 1.81
0. 38 6.44 2.00
0.29 0.83 2.54
0.20 1.44 2.37
0.23 2.53 1.69
0.56 7.04 1.52
0.38 3.72 1.75
0. 31 2.46 1.72
#
CVS-CH test procedure
Equipped with catalyst similar to Group I at Riverside. These vehicles
have higher CO levels than the durability cars running at Riverside because
of an effort to reduce NOX to levels somewhat more typical of what would be
required for a 1975 model.
2-35
-------
Only limited high mileage emission data are available from the Ford first-
choice system being tested at Riverside. These results are presented in
Table 2-10. It should be noted that the two Fords and the F-100 #2 are the
only Group I vehicles which continue to meet the 1975 standards at
8000 miles.
2.2.3.1.3.4 Best Emission Results
The best low mileage emission results (average of two tests), reported by
Ford for their first-choice test vehicles are presented in the table below.
All results are at zero or low mileage with the exception of the F-100 pickup
truck. For this vehicle, the best results were obtained at 4,000 miles.
Best Emission Results -- Ford First-Choice System
Vehicle Miles HC CO NO
Maverick #2
Ford #2
F-100 #2
Lincoln #2
Mercury
0
0
4,000
0
*
0.32
0.20
0.33
0.43
0.23
0.95
1.75
2.11
2.88
1. 03
x.
2.92
2.46
2.74
2. 16
1. 14
*
Reported only as "low mileage."
The best high mileage emission results achieved on a single test on the Ford
first-choice system were obtained on the Ford Galaxie #1 being tested at
Riverside. These results, at 8, 000 miles, were 0.25, 1.84, and2.55gm/mi
for HC, CO, and NO , respectively.
.X
2.2.3.1.3.5 Test Data Variability
Test data variability at the 1975-76 emission levels has been reported by
Ford (Ref. 2-8) in terms of the coefficient of variation, o-/x%, for test-to-test
variability, as follows:
2-36
-------
Table 2-10. High Mileage Emission Results Ford First-Choice
System (Riverside Test Fleet)
Vehicle
Maverick #1
Maverick #2
Ford #1
Ford #2
F-100 #1
F-100 #2
Lincoln #1
Lincoln #2
Eng.
CID
250
250
351
351
360
360
460
460 .
Mileage
8000
8000
8000
8000
8000
8000
8000
8000
;';
Emissions, gm/mi
HC CO NO
0.78 2.28 3.37
0.66 2.37 3.46
0.56 3.85 3.29
0.25 1.84 2.55
0.23 2.32 2.45
0.24 2.45 2.45
0.28 2.26 2.85
0.45 5.37 2.48
0. 31 2. 12 2.42
0.37 4.12 2.74
0.57 3.63 2.40
0.59 4.34 3.15
Remarks
1 test only
1 test only
1 test only
1 test only
'CVS-CH test procedure
2-37
-------
Ford Test Data Variability
(Coefficient of Variation, (r/x, %)
Emission -Test-to-Test
HC 20 - 26%
CO 19 - 34%
NO 10 - 23%
Although the small sample size of the data available from the Phase I dura-
bility tests on a given vehicle does not permit an accurate determination of
the coefficient of variation, evaluation of the spread in the Riverside data
indicates that the results to date are consistent with the test-to-test
variability reported by Ford.
2.2.3.2 Alternate Systems
2.2.3.2.1 Special Design Features
Two alternate emission control systems are currently being tested by Ford
at Riverside and Dearborn. These are the Group II (dual catalysts plus
thermal reactor) and the Group III (dual catalysts only) vehicles described in
detail in Section 2. 2 . 3 . 1. 3 . 1. A third system, designated Group IV, will
also be tested following a decision on the components to be used based on the
resuHs obtained from the Group I, n and III vehicles.
2.2.3.2.2 Problem Areas and Plans for Resolution
As previously stated, Ford's primary problem concerns the durability of
the emission control system. Accordingly, the Group II, III and IV vehicles
are also being evaluated on the AMA durability driving cycle to determine the
best combination of emission system components required to meet the 1975
emission standards over the 50,000-mile range.
2-38
-------
Ford indicates that they plan to continue the investigation of the catalyst plus
thermal reactor system vehicles as well as the thermal reactor-only system.
However, a project recently completed by the Ford Car Research Office
implies that a basic incompatibility may exist between reactor manifolds and
catalytic converters. Material deposits were found in the catalyst which were
thought to originate from the stainless steel liner of the reactor manifold.
Ford speculates that these deposits may contribute to the overall deterioration
of the combined system, thus causing it to deteriorate more rapidly than the
catalyst-only system. Investigations attempting to resolve this issue are
continuing.
2.2.3.2.3 Emissions
2.2.3.2.3.1 Test Programs and Vehicle Descriptions
AMA durability tests are being conducted at Riverside on Group II and III
cars. Similar durability tests will begin in the near future on Group IV cars
as part of the Ford Phase I program. Phase II (see Section 2.2.3. 1.3. 1)
emission testing is being done concurrently at Dearborn.
2.2.3.2.3.2 Test Procedures
All emission data is being obtained in accordance with the 1975 CVS-CH test
procedure.
2. 2. 3 . 2. 3 . 3 Emission Data Summary
Low mileage emission results for the Ford dual catalyst plus thermal reactor
system being tested on the Group n vehicles at Riverside and Dearborn are
shown in Table 2-11. It will be noted that only a few of the Riverside Group II
vehicles met the 1975 standards. These included the Maverick #1 through
2000 miles, Ford # 1 at 2000 miles only, the F-100 #2 at 4000 miles only, and
the Lincoln # 1 at 0 miles only. Of the Dearborn cars, only the F-1.00 pickup
truck met the standards at 0 and 4000 miles.
2-39
-------
Table 2-11. Low Mileage Emission Data--Ford Alternate
System (Group II)
Vehicle
Riverside Test Fleet
Maverick #1
Maverick #2
Ford #1
Ford #2
F-100 #1
F-100 #2
Lincoln #1
Lincoln #2
Engine CID
250
250
351
351
360
360
460
460
Mileage
0
2000
4000
0
2000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
0
2000
4000
*
Emission, gm/mi
HC CO NO
X
0.22 3.23 1.76
0.32 2.98 2.02
0.52 5.06 1.86
0.54 8.74 1.68
0.44 5.53 1.81
0.36 3.72 2.17
0.27 2.93 2.06
0.40 4.82 2.08
0.32 4.21 1.76
0.40 4.65 1.88
0.32 5.58 1.57
0.38 4.45 1.44
0.39 4.99 1.62
0.40 5.63 1.75
0.24 3.96 3.12
0.25 3.43- 2.55
0.26 3. 16 1.91
0.23 2.22 2.33
0.27 4.29 2.63
0.26 3.58 2.33
0.32 4.51 1.97
0.35 6.28 2.02
0.37 5.60 2.17
Remarks
1 test only
CVS-CH test procedure
Average of two consecutive tests at each mileage point unless otherwise
indicated.
2-40
-------
Table 2-11.
Low Mileage Emission Data--Ford Alternate
System (Group II) (Cont. )
Vehicle
Dearborn Test Fleet
Maverick
Ford
F-100
j
Lincoln
Engine CID
250
351
360
460
Mileage
0
4000
0
4000
0
4000
0
4000
*
Emission, gm/mi
HC CO NOx
0.49 2.59 1.55
0.48 3.31 1.94
0.43 2.90 1.95
0.28 3.98 2.15
0.39 4.74 2.21
0.33 5.85 2.33
0.22 4.44 1.95
0.16 0.72 1.81
0.10 0.68 1.40
0.23 0.92 2.14
0.21 2.04 1.72
0.57 7.00 1.59
0. 19 1.49 1.60
0.23 4.44 1.43
Remarks
1 test only
1 test only
CVS-CH test procedure
f Equipped with thermal reactor and extra catalyst similar to Group III at
Riverside. These vehicles have higher CO levels than the durability
cars at Riverside because of an effort to reduce NOX to levels somewhat
more typical of what would be required for a 1975 model.
2-41
-------
The primary problem with the Group II vehicles appears to be a general
inability to meet the CO standard of 3.4 gm/mi.
Low mileage emission results reported to date for the Ford dual catalyst-
only system, undergoing test at Riverside and Dearborn on the Group III
vehicles, are shown in Table 2-12. All of the Riverside Group III vehicles
met the 1975 standards at 0 miles with the exception of the Lincoln #2. How-
ever, only the Fords and F-100 pickup trucks continued to meet the standards
at 2000-4000 miles. None of the Dearborn Fleet Vehicles met the standards
at either 0 or 4000 miles.
No high mileage emission data have been reported for the Ford Group II and
III cars undergoing durability testing at Riverside. Approximately 12,000
miles have been accumulated on a Maverick/Comet 302 CID V-8 with an
emission control system similar to the Riverside Group III cars; i.e. , dual
catalysts in series without a thermal reactor. Results are shown in Table 2-13
It will be noted that although this vehicle continued to meet the NO standard
7C
over the mileage tested, HC and CO emission control deteriorated between the
3129-mile and 5803-mile test points; thereafter, the HC emissions exceeded
the 1975 standards.
Two of Ford's earlier high mileage test programs that are obliquely related
to the current durability evaluation may be mentioned. One of these, desig-
nated as the 1975 Durability Test Program, involved the test of six develop-
ment "Concept Emission System" vehicles equipped with thermal reactor,
catalytic converter, EGR, secondary air injection, and quick release choke.
These vehicles were tested over the AMA durability driving cycle; emission
results were obtained in accordance with the 1972 CVS-C test procedure.
Although these vehicles were tested up to 50,000 miles, this mileage value
does not represent the accumulated emission system mileage since numerous
system component failures occurred and replacements were made during the
course of the test. A representative set of failure incidents is given by the
2-42
-------
Table 2-12. Low Mileage Emissions--Ford Alternate
System (Group III)
Vehicle
Riverside Test Fleet ' '
Maverick #1
Maverick #2
Ford #1
Ford #2
F-100 #1
F-100 #2
Lincoln #1
Lincoln #2
Engine CID
250
250
351
351
360
360
460
460
Mileage
0
2000
4000
0
2000
0
2000
4000
0
2000
0
2000
0
2000
4000
0
2000
0
2000
Emissions, gm/mi '
HC CO NO
X
0.32 0.60 2.34
0.31 1.11 3.09
0.37 0.95 3.36
0.21 1.73 2.08
0.60 2.18 2.70
0.17 1.77 2.26
0.20 1.51 2.20
0.28 1.56 2.45
0.26 1. 53 2. 19
0.34 1.46 2.26
-0.34 4.71 2.05
0.40 4.01 1.98
0.32 1.71 2.09
0.44 1.23 1.95
0.34 2.22 2.35
0. 28 1. 59 2. 10
0.31 3.55 2.59
0.24 4.26 2. 18
0.31 5.68 1.99
CVS-CH test procedure
Average of two consecutive tests at each mileage point
2-43
-------
Table 2-12. Low Mileage Emissions--Ford Alternate
System (Group III) (continued)
Vehicle
;'c >'"
Dearborn Test Fleet' '
Maverick
Ford
F-100
Lincoln
Engine CID
250
250
360
460
Mileage
0
4000
0
4000
0
4000
0
4000
*
Emissions, gm/mi
HC CO NO
X
0.49 10.2 1.70
0. 56 11. 2 2. 12
0.62 14.5 2.32
0.58 12.9 1.69
0.31 4.61 1.81
0.35 6.00 1.87
0.28 6. 81 1. 17
0.28 3.92 1.86
0.25 0.67 2.46
0.40 3.78 1.63
0.44 5.90 1.46
0.66 5.24 1.70
0.62 9.44 0.94
0.69 11.70 1.01
0.99 17.43 0.89
1.06 15.99 0.99
CVF^CH test procedure
'-
i" _
Equipped with extra catalyst similar to Group III at Riverside. These
vehicles have higher CO levels than durability cars running at Riverside
because of an effort to reduce NOX to levels somewhat more typical of
what would be required for a 1975 model.
2-44
-------
Table 2-13. High Mileage Emission Data--Ford Alternate
System (Group III Type)
Vehicle
Maverick /Comet
302 CID
-
Miles
103
128
207
220
844
870
3035
3114
3129
5803
5821
5888
5928
5952
12060
12088
12108
Emissions, gm/mi
HC
0.22
0.20
0.26
0.26
0. 37
0.31
0. 35
0.53
0.35
0.62
0.56
0.88
0.63
0.73
0.76
0.80
0.59
CO
0.97
1.29
3.07
1.45
4. 18
2.39
3.07
2.57
1.90
3. 32
2.94
5.43
3.07
5.01
4. 71
4.51
2.84
NO
X
2.62
1.51
1.52
1.69
1.59
1.69
1.67
1.71
1.72
2. 12
1.92
2.39
2.22
1.94
1. 61
1.96
2.20
Remarks
EGR Increased
Change power
valves from 5. 5
to 3. 0 in Hg
Timing at 3° ETC.
Change oil & filter
Set timing back to
6° ETC
2-45
-------
test history for vehicle 12A90, a 1971 351-CID Ford. Emission system
components and component failures or malfunctions for this test vehicle are
described in Table 2-14; test emission results for HC and CO are shown in
Figure 2-14. (NO levels were below the 1975 standard throughout the test.)
The other earlier high mileage test program involved a developmental fleet
of five durability vehicles. The test program was started in mid>-1971 to
evaluate the possibility of meeting the 1974 California standards using a
catalyst-only system (without thermal reactor) in conjunction with EGR,
secondary air injection, and a quick-release choke. The use of this system
for the 1974 model year was abandoned when it was established that lead-free
fuel would not be available.
Basically, this fleet represents a developmental predecessor of the Group I
vehicles currently undergoing test at Riverside and Dearborn. Approximately
50,000 miles were accumulated on each vehicle over the AMA durability test
route. Emission results were obtained in accordance with the 1972 CVS-C
test procedure.
Durability testing of the 1974 California model year vehicle resulted in
numerous failures of emission components including catalytic converters,
overtemperature controls, EGR components, air injection system components,
carburetion, ignition, and engine components. Repairs and/or replacements
were made as required during the course of each test and, as a result, the
total vehicle durability miles do not represent emission control system
durability mileage.
Typical results obtained during this test are shown for Vehicle 1A97, a 1971
400-CID Ford, in Figure 2-15 (HC and CO) and Figure 2-16 (NO ). The HC
and CO emission levels exceeded the 1975 standards while that of NO
remained well below the standard throughout the test. Emission system
components and component failures or malfunctions for this test vehicle
are described in Table 2-15.
2-46
-------
Table 2-14. Durability Test Vehicle Specifications (Vehicle No. 12A90-D)
Type: 1971 400-2V A/T Ford
Test Program: 1975 AMA Durability
Emission System Components
Reactor cylinder heads with exhaust port liners
Phase III spacer EGR, pickup before muffler and through cooler, cold
lockout (125°F PVS)
19 in air pump with 1. 5:1 drive ratio. Replaced 1. 7:1 drive ratio
70F57 S. D. distributor @ 6° BTC initial with cold lockout of part
throttle advance (125°F PVS)
2100 2V GPD carburetor with ACE 39 calibration and 20 sec
Schmelzer quick choke and 5 sec. restrictor
Phase I type "H" reactors with core
Monolithic PTX 5.35 converters
Emission Component Failures or Malfunctions During Durability
30,000 Miles - Converters failed; installed new PTX 5.35 converter
- Air pump ratio changed from 1. 7:1 to 1. 5:1
35,000 Miles - Air pump failed; installed new pump
- Transmission failed; installed new transmission
Various mileages - Left hand reactor outlet gasket failed 9 times
during durability causing engine mount failure
at 26, 500 miles
1971 400-3V FORD I2A90-D
PTX 5.35 CONVERTERS-UEACTORS-EGR
HYDROCARBON
NEW
CONVERTERS-
CARBON MONOXIDE
NEW
CONVERTERS -
100
u 80
60
40
20
RT. CONVERTER
FAILED
EMISSIONS
NEW CONVERTERS
"^T
10 X 30
TEST MILES, 000
40
10 20 30
TEST MILES. 000
30
20
10 52
40
Figure 2-14. Ford AMA Durability Data
2-47
-------
Table 2-15. Durability Test Vehicle Specifications (Vehicle No. 1A97-D)
Type: 1971 400-2V A/T Ford
Test Program: 197.4 Model Year California
Durability
Emission System Components
Cylinder heads with port air injection
EGR into the carburetor, spacer, pickup before muffler and
through a cooler
19 in air pump with 1.37:1 drive ratio was used through the
30, 000 mile test. Changed to 1. 50:1 before the 35, OpO mile test
Single diaphragm distributor with production calibration.
Initial timing 6°BTC
Carburetor calibration No. ACE 39. Idle CO set to 2.5% at
an idle speed of 560 rpm
Monolithic PTX 5.2 converter used on left-hand side and monolithic
PTX 5. 35 used on right-hand side
Total Durability as of 4/20/72
50, 000 miles, test completed
Emission Component Failures or Malfunctions During Durability Period
EGR vacuum switch failed
Schmelzer valve found defective and replaced
Choke shaft replaced
Number of Emission Test Conducted
15 prior to start of durability
18 during the durability period
2-48
-------
1971 400-2V FORD-1A97
PTX-535 CONVERTERS
HYDROCARBON
CARBON MONOXIDE
10 20 30
TEST MILES, 000
20 30
TEST MILES, 000
Figure 2-15. Ford AMA Durability Data
1971 400-2V FORD 1A97
PTX-5.35 CONVERTERS-EGR
40
S 20
I I I
OXIDES OF NITROGEN
_ STD
I I
10 20 30 40
TEST MILES, 000
SO
Figure 2-16. Ford AMA Durability Data
2-49
-------
2.2.3.2.3.4 Best Emission Results
The best low mileage emission results for the Group II and III vehicles being
tested at Riverside are shown in the table below. Results are for zero miles
unless otherwise indicated. In addition to the Riverside test vehicles, data
are also shown under Group III (dual catalysts only) for the best emission
results achieved on a Maverick V-8 development car at approximately
125 miles.
Best Emission Results -- Ford Alternate Systems (Groups II and III)
Riverside
HC CO NO
x
Group II (Dual Cats, and Reactor)
Maverick, 6 cyl. 0.22 3.23 1.76
Ford 0.36 3.72 2.17
F-1002 0.32 4.21 1.76
Lincoln 0.23 2.22 2.33
Group III (Dual Cats. Only)
Maverick, 6 cyl 0.21 1.73 2.08
Ford 0.26 1.53 2.19
F-1002 0.32 1.71 2.09
Lincoln 0.28 1.59 2. 10
Maverick, V-8 0.20 1.29 1.51
Average of two consecutive tests
2At 2,000 miles.
2.2.3.2.3.5 Test Data Variability
The Riverside test data for the Ford dual catalyst plus thermal reactor
equipped vehicles (Group II), and the dual catalyst-only vehicles (Group III),
exhibit a greater spread than do the data from the Ford first-choice system
which employs the single catalyst. This is consistent with the Ford statement,
2-50
-------
(Ref. 2-9) that "systems with many specific control devices have greater
variability as each added device contributes its own degree of variability. "
The small data sample size does not permit a meaningful evaluation of the
coefficient of variation.
2.2.3.2.4 Fuel Consumption and Performance Penalties
Fuel consumption and performance penalties for the Ford alternate (Group II
and III) systems were not discussed. Some performance information was
provided for the 302-CID Maverick developmental vehicle. This vehicle is
equipped with the dual catalyst system and is comparable to the Group III
vehicle. At 5800 miles, the average driveability was reported as 6 (on a
scale of 10), ranging from 5 on light acceleration to 7 at WOT. Fuel con-
sumption penalties were not reported.
2.2.4 General Motors
2.2.4.1 First-Choice Systems
2.2.4.1.1 Special .Design Features
The General Motors first-choice system comprises the following subsystems
(Refs. 2-11 through 2-15):
Catalytic converter (base metal/particulate)
Secondary air supply (AIR)
Exhaust gas recirculation (EGR)
Engine modifications
Modified carburetor with altitude compensation and
fast acting choke
Modified intake system with quick heat manifold to produce
early fuel evaporation (EFE)
Modified exhaust system acting as a partial thermal
reactor
Electronic ignition system
Modified spark timing
2-51
-------
The system is illustrated in Figure 2-17. It was selected on the basis of the
following considerations:
a. 1975 emission levels were approached, at low mileage.
b. Many of the components use existing technology; the only
exception is the catalytic converter.
c. The system can be readily modified for 1976 NO control.
d. The system involves a minimum number of vehicle
compromises.
The base metal/particulate catalyst converter was selected over the noble
metal /monolithic catalyst converter for a number of reasons. General Motors
states that it is cheaper, more readily available, has better deterioration
and durability characteristics, and is less subject to poisoning. The light-off
(50 percent conversion efficiency) temperature is said to be about the same as
the monolithic type at zero miles.
With regard to change in light-off temperature with use, GM 24-hour soak
tests are reported to show that the light-off temperature of the noble metal
converter increases linearly with increasing soak temperature, whereas the
base metal catalyst retains its low light-off temperature at soak temperatures
as high as 1800 F. This is regarded as proof that the base metal pellet
system has greater ability to withstand overtemperature conditions. In addi-
tion, the GM data indicate that the activity of the base metal catalyst starts at
lower temperature.
Another GM consideration concerning the selection of the pelletized catalyst
was that the pellets might be readily and cheaply replaced, an advantage that
may be particularly significant if maintenance is authorized at mileage inter-
vals under 50,000 miles.
The EFE manifold is used on the first-choice system in conjunction with an
improved carburetor and choke components to improve the cold start emis-
sions. The electronic ignition system is included to permit engine operation
2-52
-------
-AIR INJECTION
PUMP
QUICK HEAT
MANIFOLD (EFE
IMPROVED CARBURETION AND CHOKE
ALTITUDE AND TEMPERATURE
COMPENSATION
ui
Oo
EXHAUST GAS
RECIRCULATION
MODIFIED SPARK
TIMING
CATALYTIC
CONVERTER
PCV VALVE
DOMED TANK
VAPOR SEPARATOR
-CARBON
CANISTER
-ELECTRONIC
IGNITION
Figure 2-17. General Motors First-Choice 1975 Emission Control System
-------
with leaner air/fuel mixture ratios while still retaining acceptable
driveability and improved reliability over the life of the vehicle.
2.2.4.1.2 Problem Areas and Plans for Resolution
Further development is said to be needed to improve the durability of the
catalytic converter and of the EGR valve. Testing of these systems is being
actively pursued. General Motors feels that physical durability of the pellets
is no longer a problem. Catalyst shrinkage has been limited to 10 percent
for a 24-hour soak at 1800 F. Sulfur poisoning, which is a very serious
problem at catalyst bed operating temperatures below 1300 F, has been
shown to be much milder above 1300 F. For this reason GM may decide
to operate their converter above 1300 F instead of the present nominal
operating temperature of 900 to 1200 F.
Durability of the EGR valve is still not adequate and design improvements
will be checked out during road testing under various loads. The EFE mani-
fold and the electronic ignition systems are still at the engineering prototype
level. More experimental work is required prior to committing a specific
design to production.
2.2.4.1.3 Emissions
2.2.4.1.3.1 Test Programs and Vehicle Description
According to GM, a total of 380 catalytic converter systems have been built
aad . osted during the last 2 years. Emission test results from 50 low mileage
experimental systems were included in the GM submission. These encompass
tests on a variety of catalytic converter types and makes, including base and
noble metal pellet and noble metal monolithic designs.
For certification, General Motors requires a minimum of 13 cars to meet
the 1975 Federal standards. In addition to the certification test fleet, GM
will pre-test 13 similar vehicles to verify the emissions and durability. A
concurrent test program will check out the cars from the standpoint of
2-54
-------
driveability, fuel consumption, safety, mechanical durability, etc. , under
customer driving and variable weather conditions. This will be done on the
GM proving ground. Because of the large number of models, engines, and
transmission options provided, the test program will be designed on a
statistical basis to verify satisfactory performance and operation over the
broad spectrum of hardware combinations. The number of cars to be tested
in this program have not yet been determined.
In addition to the above, GM is operating a baseline test fleet of 18 vehicles
to test the durability of the catalytic converter canister.
2.2.4.1.3.2 Test Procedures
All recent testing has been conducted using the 1975 CVS-CH Federal Test
Procedure. Durability testing is accomplished using a modified AMA driving
schedule.
2.2.4.1.3.3 Emission Data Summary
Low mileage emission data submitted by GM are shown in Table 2-16; high
mileage data are presented in Table 2-17. Each entry represents a single
test and should be viewed with due regard for the high degree of test-to-test
variability discussed in Section 2.2.4. 1.3.5.
For the most part, these data represent the experimental system vehicles
which are closest to GM's description of the total first-choice package required
for the 1975 model year vehicle. It will be noted that not all of the vehicles
are equipped with the full complement of components for the first-choice
system. Carburetor altitude compensation and electronic ignition components,
which are among the missing items, are stated by GM to have little impact
on EPA test emissions results. The quick heat EFE manifold is missing on
many cars because of the lack of advanced design engine components available
for experimentation. GM states that this is not particularly important in
evaluating the emission performance of these vehicles since they are not
equipped with the appropriate chokes for low CO EFE performance anyway.
2-55
-------
Table 2-16. General Motors Low Mileage Emissions
ro
i
Car
No. Car & CID
61336 Chev. 350
61341 Chev. 350
61340 Chev. 350
61355 Chev. 350
61358 Chev. 350
61317 Chev. 350
61318 Chev. 350
61319 Chev. 350
61339 Chev. 402
61329 Chev. 402
61324 Chev. 402
62504 Pont. 455
62505 Pont. 455
1938 Pont. 455
2586 Olds 350
2611 Olds 350
2541 Olds 350
Oxidizing Catalyst
Type' Supplier
BB Grace
Davex 117
BB Grace
Davex 117
BB Grace
Davex 117
BN Universal Oil
PZ-2-168 R-5
BN Universal Oil
PZ-2-168 R-5
BB Oxy-Catalyst
G-623-71 No Prom.
BB APCC
MN Engelhard PTX-4
BB Grace
Davex 117
BB Monsanto
NBP-701094
BB Grace
Davex 1 1 7
BB Universal Oil
PZ-1-224-1
BB APCC
BB Monsanto
ECA-125
BB APCC .
1259JX3-1X1
BB Universal Oil
PZ-1-224-1
BB Oxy-Catalyst
System Description
Mod.
AIR EGR Carb. EFE
XX X
XX X
XX X
XX X
XXX X
XX X
XX X
XX X
XX X
XX X
XX X
XX X
XXX X
XXX X
XX X
XX X
XX X
Test -Test Test
Weight Date Mileage
4500 7-71 800
4500 8-71 400
4500 8-71 150
4000 2-72 700
4500 1-72 80
4500 10-71 0
4500 12-71 0
4500 8-71 0
4500 10-71 100
4500 2-72 2,934
4500 6-71 1,000
4500 11-71 100
4500 4-72 6
4500 12-71 400
5000 2-72 42
5000 1-72 1
5000 3-72 9
1975 CVS-CH Emissions,
gm/mi(2)
HC CO NOX
0.30 7.0 1.3
0.50 7.0 1.1
0.60 10.0 1.4
0.30 2.7 0.8
0.33 2.4 0.9
0.47(89) 6.7(75) 1.4
0.25(76) 2.9(71) 1.9
0.13(84) 1.9(83) 1.3
0.37 12.8 0.8
0.55 3.8 1.0
0.36 4.1 0.9
0.34 2.4 0.9
0.20 0.8 1.4
0.41 5.4 1.5
0.28(83)* '7.3(67)* 3.7
0.24(82)* 9. 1(55)* 1.9
0. 17(88)* 2.7(82)* 2.2
Status
Co-op development
(Arvin)
Co-op development
(Norris)
Co-op development
( Walker i
System development
System development
Durability test
Durability test
Durability test
System development
Durability test
Crosscheck car
System development
System development
System development
Durability test
Durability test
Durability test
See notes on last sheet.
-------
Table 2-16. General Motors Low Mileage Emissions (Continued)
m
-j
Car
No. Car &c CID
61420 Olds 455
62403 Olds 455
62411 Olds 455
2826 Buick 455
2242 Buick 350
4231 Buick 350
62102 Buick 455
2827 Buick 455
62115 Skylark 455
9168 Buick 455
8245 Buick 455
61125 Buick 455
5274 Buick 455
8195 Buick 455
2828 Buick 455
Oxidizing Catalyst
Type Supplier
BN Universal Oil
PZ-2-168-R-5
BB APCC
1259 JX3-1X1
BB APCC
1259JX3-1X1
BB Degussa
OM56ET
BB APCC
1259JX3-1X1
BB Oxy-Catalyst
BB APCC
12591X3-1X1
BB Grace
Davex 142 SMR 7-388
BB APCC
1259JX3-1X1
BB Universal Oil
PZ-1-225-1
BB Universal Oil
PZ-4-214 R-14
BB Monsanto
ECA-125
BB Universal Oil
PZ-4-214 R-14
BB Universal Oil
PZ-4-214 R-14
BB Monsanto
ECA-141
System Description
Mod.
AIR EGR Carb. EFE
XX X
XX X
XX X
X X
XX X
XX X
XXX X
X X
1
XXX X
XX X
XX X
X X X
XX X
XX X
X X
Test Test Test
V.'eight Date Mileage
5000 12-71 100
1-72 275
1-72 400
2-72 860
2-72 874
3-72 1,126
3-72 1,134
4-72 2,257
5000 2-72 118
5500 1-72 240
5000 3-72 10
4500 3-72 0
4500 2-72 0
5500 2-72 1,689
5000 2-~2 88
4500 4-72 280
5000 3-72 650
5000 2-72 300
5000 2-72 2,500
5000 3-72 300
5000 3-72 1.644
5000 3-72 0
1°75 CVS-CH Emissions,
HC CO NOX
0.20 2.6 .0
0.40 5.2 .5
0.40 2.6 .0
0.27 3.9 .1
0.27 3.2 .1
0.26 2.1 1.2
0.25 2.9 1.0
0.3^ 3.2 1.1
0.45 -. } 1.0
0.52 5.0 0.9
0. 38(781* 3. 5(851* 3. 3
0.56 3.9 1.8
0.64 6.8 2.5
0.63 3.2 1.0
0.27(79)* 4. 2(71)* 3. 7
0.70 2.5 0.9
0.31 2.7 1.7
0.23(81)* 2. 8(911* 1. 4
1.00 7.6 0.9
0.44 2.3 1.5
0.25 2.5 1.0
0. 14(391* 3. 8(75)* 3. 1
Status
Durability test
System development
System development
Durability test
Durability test
Durability test
System development
Durability test
System development
System development
System development
System development
System development
System development
Durability test
See notes on last sheet.
-------
Table 2-16. General Motors Low Mileage Emissions (Continued)
NJ
1
Ul
00
Car
No. Car & CID
2822 Buick 455
2823 Buick-455
2824 Buick 455
2825 Buick 455
BAK Buick 455
934 Buick 455
933 Buick 455
61202 Cad 472
61206 Cad 472
61201 Cad 472
61203 Cad 472
1246 Cad 500
2222 Cad 500
1420 Opel 1.9 lit
1450 Opel 1.9 lit
Oxidizing Catalyst
Type Supplier
BB Oxy-Catalyst
G-1313
BB Grace
Davex 142 SMR 7-38£
BB Oxy-Catalyst
G-1313
BB Oxy-Catatyst
BB Universal Oil
PZ-4-214 R-14
BB Universal Oil
PZ-1-224-1
BB Oxy-Catalyst
BB Monsanto
ECA-125
BB Monsanto
ECA-125
BB Universal Oil
PZ-4-214 R-14
BB APCC
1259JX4-1X1
BB Grace
Davex 117
BB APCC
1259JX3-1X1
MN Engelhard PTX
BB Grace
Davex 117
System Description
Mod.
AIR EGR Carb. EFE
X X
X X
1
X X
X X
X X
X X
X X
XXX X
XXX X
XX X
XX X
XX X
XX X
X X . X
XX X
Test Test Test
Weight Date Mileage
5000 1-72 0
5000 1-72 0
5000 1-72 0
5000 3-72 0
5000 11-71 21
5000 1-72 0
5000 11-71 0
5500 2-72 1,000
55'0 2-72 1,200
5000 1-71 50
5500 2-72 300
5500 1-72 0
5500' 1-72 0
2500 2-72 0
2500 12-71 0
1975 CVS-CH Emissions,
em/m'{2)
HC CO NOX
0.41(67)* 5. 7(45)* 3. 5
0.20(84)* 4.7(51)* 2.9
0 33(81)* 3. 0(74)* 3. 7
0. 31(79)* 4.6(74)* 3. 3
0. 17(88)* 1.8(87)* 3. 7
0.25 2.7 2.0
0. 19 1.8 2. 4
0. 92 6. 8 0. 9
0.51 4.6 0.9
0.16 5.9 1.0
0.25 6.0 0.9
0.27 1.7 2.9
0.35 1.1 2.0
0.23 2.7 1.5
0.53 10.4 1.7
Status
Durability test
Durability test
Durability test
Durability test
Durability test
Durability test
Durability test
System development
System development
Durability test
System development
Syatem development
Durability test
System development
Durability test
Note: Emissions data reported for each vehicle represent one test only.
(1) Type: BB = Bulk base metal APCC = Air Products and Chemicals Co (Houdry)
BN = Bulk noble metal
MN = Monolith noble metal
MB = Monolith base metal
(2) Catalyst conversion efficiency shown in parentheses - %
* Efficiency calculated from with and without -converter tests not from simultaneous test.
-------
Table 2-17. General Motors High Mileage Emissions
N)
Car
No. Car tc CID
61319 Chev. 350
61318 Chev. 350
61317 Chev. 350
Dev. Chev. 400
61329 Chev. 402
2014 Olds 350
2611* Olds 350
2494b Olds 455
2823a Olds 455
2249a Olds 455
2850 Olds 455
Oxidizing Catalyst
Type"' Supplier
MN Engelhard
PTX-4
BB APCC
BB Oxy-Catalyst
G-623-71
BB Oxy-Catalyst
BB Monsanto
NBP-70194
BB Grace -Davex
142 SMR-7-3881
BB Universal Oil
PZ-1-224-1
BB Grace - Davex
142 SME 7-3881
BB Oxy-Catalyst
BB APCC
1259JX3-1X1
BB' Oxy-Catalyst
BB Oxy-Catalyst
System Description
Mod.
AIR EGR Carb. EFE
XX X
XX X
X X . X
X
XX X
X X
XX X
XXX
X
X X'
X X
X X
Test .Test .Test
Weight Date Mileage
4500 8-71 0
11-71 8,424
2-72 21,52,7
4500 12-71 0
4-72 Z1.178
4500 10-71 0
3-72 32,014
5000 12-71 0
3-72 5,544
4500 7-71 126
8-71 229
9-71 627
10-71 825
2-72 2,934
4-72 5.550
4500 2-72 20
3-72 3,034
4-72 6,436
5000 1-72 1
2-72 6,145
5000 2-72 0
3-7Z 6,337
4-72 12,022
5000 1-72 0
2-72 2,548
3-72 4,615
3-72 6,097
4-72 9,280
5500 1-72 10
1-72 3,336
2-72 8,927
4500 1-72 54
4-72 6,400
5500 1-72 0
2-72 3,235
2-72 6.447
3-72 12,257
4-72 18,000
. 1975 CVS-CH Emissions.
gm/mi(2)
HC CO NOX
0.13(84) 1.9(83) 1.3
0.51(65) 4.9(77) .4
0.55(76) 5.5(70) .6
0.25(76) 2.9(71) .9
0.87(58) 4.1(64) .6
0.47(89) 6.7(75) .4
1.20(73) 13.6(50) .4
0.19 2.0 5.9
0.51 5.4 5.3
0.47 4. 0 1.1
0.91 3.2 1.5
0.74 4.5 1.2
0.85 2.5 1.1
0.55 3.8 1.0
0.55 8.8 1.1
0. 59(71)* 11. 1(47)* 2. 1
0.70 11.6 2.0
0. 89(54)* 15. 5(10)* 2.9
0.24(82)* 9. 1(55)* 1.9
1.4 14.6 2.6
0.40(71)* 9. 0(39)* 2. 3
0.52 17.7 2.4
0.91 24.0 2.2
0.20(33)* 9.2(27)* 3.2
0.62 11.0 4.2
0.53 8.2 4.5
0.63 7.2 3.5
1.02 7.7 3.3
0. 34(72)* 10.7(16)* 2. 1
0.41 10.3 2.0
0.62(51)* 11.6(30)* 2.0
0. 27(7B)« 10.8(70)* 1. 7
0.48 11.9 1.3
0. 31(75)* 10. 5(-8)« 2. 0
0.34 9.7 2.6
0.55 7.8 1.2
0.53 9.2 2.6
0.53 7.4 2.7
Status
Test continuing
Test 'continuing
Test continuing
Test continuing
Test continuing
Test continuing
Terminated; catalyst
lost
Test continuing
Test continuing
Test continuing
Test continuing
Test continuing
See notes on last sheet.
-------
Table 2-17. General Motors High Mileage Emissions (Continued)
Car
No. Car & CID
2233 Olds 455
4231 Buick 350
62124 Buick 455
62125 Buick 455
62126 Buick 455
933 Buick 455
BAK Buick 455
931 Buick 455
2222 Cad. 500
1450 Opel 1.9 lit.
Oxidizing Catalyst
Type'1' Supplier
BB APCC
1259JX3-1X1
BB Oxy-Cataly«t
BB APCC
1259JX3-1X1
BB APCC
1259JX3-1X1
BB APCC
1259JX3-1X1
BB Universal
Oil Products
PZ-4-214-R-14
BB Universal
Oil Products
PZ-4-214-R14
BB APCC
1259JX3-1X1
BB APCC
1259JX3-1X1
BB Grace
Davex 117
System Description
Mol.
AIR EGR Carb. EFE
X X
XX X
X X
X X
X X
X X
X
X X
XX X
XX X
Test Test Test
Weight Date Mileage
4500 12-71 0
1-72 14,227
1-72 19,868
2-72 24,304
3-72 30,037
4500 2-72 0
2-72 1,600
3-72 4,200
4-72 7,600
5000 2-72 43
2-72 2,910
3-72 7,280
3-72 10,097
5000 2-72 32
2-72 3,201
3-72 7,198
3-72 10,469
5000 2-72 33
2-72 3,381
3-72 7,096
3-72 10,079
500o .11-71 0
12-71 7,798
1-72 19,106
2-72 27,161
2-72 38,661
3-72 43,179
4-72 46,301
5000 11-71 21
11-71 31
1-72 2,805
4-72 12,980
5000 12-71 0
1-72 7,544
5500 1-72 0
1-72 2,000
2-72 4,000
4-72 8,000
1500 12-71 0
1-72 12,000
2-72 23,000
1975 CVS-CH Emissions
gm/mi(2)
HC CO NOX
0.31(85)* 5.6(51)* 2. 1
0.48 10.7 1.6
0.52 11.7 1.6
0.56(10)* 8.6(18)* 1.9
0.73 10.6 2.3
0.64 6.8 2.5
0.76 7.7 4.2
0.66 8.2 3.7
0.81 9.5 3.7
0.38(75) 4.1(75) 5.6
1.08(48) 7.2(60) 5.3
0.43(68) 3.6(67) 4.9
0.98(43) 9.9(50) 5.9
0.64(67) 3.6(78) 5.7
0.72(52) 4.0(67) 5.7
1.16(44) 7.1(59) 5.8
1.24(36) 9.6(54) 5.7
0.54(78) 2.1(89) 6.0
0.65(56) 3.3(56) 5.5
0.67(58) 3.8(50) 4.9
0.71(59) 3.2(50) 5.1
0.19 1.8 2.4
0.36 4.4 2.8
0.44 4.3 2.0
0.51 5.6 2.2
2.71 9.3 2.6
0.90 7.5 2.3
0.78 11.7 2.1
0. 17(88)* 2.8(87)* 3.7
0.17 3.3 3.7
0.47 6.3 3.7
0.36 6.6 1.6
0.29 2.3 6.0
0.64 6.7 4.0
0.35 1.1 2.0
0.40 2.3 1.9
0.35 3.2 2.1
0.32 4.6 2.6
0.53 10.4 1.7
0.73 10.8 2.2
1.2 22.9 2.5
Status
Discontinued; high
deterioration
Test continuing
Catalyst being changed
Catalyst being changed
Catalyst being changed
Te'st stopped
Test continuing
Test stopped
Test continuing
Test continuing
Type: BB = Bulk base metal Efficiency calculated from with and without converter tests, not from simultaneous test.
MN - M^m^nnwVm,*.! APCC / Air ProducTs and Chemicals Co. (Houdry)
MB " Mono -h has tal Non-AMA Durability Schedules
MB - Monolith base metal a = K (provlng Gyroimd)> ReguUr Schedule
(2)Catalyst conversion efficiency shown in parentheses - %. b = Hill Schedule, Milford PC
Note: Emissions data reported for each vehicle represent one test only.
-------
Most of the vehicles shown in Tables 2-16 and 2-17 were equipped with base
metal/bead catalytic converters (designated BB). Included among these first-
choice system test results are GM data obtained for other catalytic converter
designs. These systems, which may be regarded as GM alternate system
candidates, include the platinum/bead system (designated BN) and the
platinum/monolith (Engelhard) system (designated MN).
Whereas GM stated in the suspension request hearing that zero mile emissions
were lower for the noble metal/monolith catalyst, but that the deterioration
factor is more severe than for its first-choice (base metal/bead) catalyst,
the test results shown in Tables 2-16 and 2-17 do not always support this
statement. For example, the emission levels for Vehicles 62505 and 933
(base metal/bead) are comparable to those for Vehicle 61319 (platinum/
monolith) at low mileage. At high mileage the emissions of Vehicles 933
and 61319 are similar.
From the data displayed in Table 2-16, GM observes that its first-choice
(BB) system shows the potential of achieving low mileage emission levels of
about 0.3 gm/mi HC, 2. 5 gm/mi CO, and 1. 5 gm/mi NO . However, GM
emphasizes that none of the systems tested has been built from production
machinery nor have attempts been made to duplicate these tests on different
vehicles. Vehicles with these initial levels are shown in Table 2-17 to exceed
the 1975 standards before 5000 miles are accumulated.
High mileage emissions are shown in Table 2-17. Vehicles appearing in this
list were driven over 4000 miles. It may be seen that all of the systems
which performed well at or below 4000 miles exceed the 1975 Federal speci-
fications at relatively low mileage.
As yet, none of the GM converters has achieved the 50, 000-mile durability
requirement. The maximum reported accumulated mileage for first-choice
systems was 46,301 miles, which was achieved with a 455-CID Buick equipped
with a UOP base metal/pellet catalytic converter designated PZ-4-214-R-14.
Emission levels at this point were 0. 78, 11.7, and 2. 1 gm/mi for HC, CO,
and NO , respectively; the test was terminated here.
5C
2-61
-------
One other high mileage data point, not included in Table 2-17 because infor-
mation concerning test procedures is lacking, may be mentioned. This data
point appeared in Attachment 2, Volume 1 of the GM supplementary material
submitted during the public hearings and was part of the data delineated in
the testimony of David Hawkins on April 26, 1972. The data concern GM
Test #472, which reports emission levels for a 455 CID, 1971 Buick as
0.37, 2.42, and 3. 44 gm/mi for HC, CO, and NO , respectively, at an
.X
accumulated mileage of 27,600 miles. The maximum mileage reported for
this vehicle was 45,300 miles, at which point the respective emissions were
0. 53, 3. 5, and 4. 0 gm/mi. General Motors states that these data are based
on the 7-mode test procedure. The vehicle emissions package included a
Monsanto ECA-125 catalytic converter. Other emissions equipment was not
specified.
2.2.4.1.3.4 Best Emission Results
Sixteen vehicles listed in Table 2-16 have all three pollutants (HC, CO, and
NO ) within the 1975 Federal standards at low mileage. The lowest overall
emission levels were obtained with car #62505 (Pontiac, 455 CID) equipped
with an Air Products base-metal/bead catalyst converter (HC = 0. 20 gm/mi,
CO -0.8 gm/mi, NO =1.4 gm/mi). Another first-choice catalyst type
X
which appears to be successful on a low mileage basis is the UOP base
metal/bead catalyst designated PZ-1-224-1. Other systems which show
promise include Oxy-catalyst and W. R. Grace (Davex 117) designs.
None of the high mileage results reported by GM meets the 1975 standard.
Good emission results at lower mileage levels were obtained with an Air
Products catalyst #1259JX3-1X1 (base metal/bead) mounted in a Cadillac
(500 CID). At 4000 miles the emissions were still within standards. At
8000 miles HC and NO emissions were still within standards (0. 32 and
x x
2. 6 gm/mi, respectively) but CO had exceeded the standard (4. 6 gm/mi).
2-62
-------
The best high mileage results, from the standpoint of mileage accumulated,
would appear to be the Test #472 data discussed in the previous section and
quoted as 0.37, 2.42 and 3.44 gm/mi for HC, CO, and NO , respectively,
Jt
at 27, 600 miles (7-mode). This test point, it may be noted, was fortuitously
selected from among other high mileage data which exceed the standards.
2.2.4.1.3.5 Test Data Variability
General Motors states that sixteen repetitive tests on one car showed a range
of 67 percent for HC measurements and 200 percent for CO measurements.
The following one-standard-deviation test-to-test variations are quoted by
General Motors: HC = ±8. 6 percent, CO = ±12. 4 percent, NO = ±15 percent.
Jt
The corresponding test cell-to-test cell variations are HC = ±24. 1 percent,
CO = ±20 percent, NO = ±15 percent. The data variability from car to car
X
of the same model is not given.
2.2.4.1.4 Fuel Consumption and Performance Penalties
The 1975 emission components and engine modifications cause an increase of
approximately 10 percent in fuel consumption.
Efforts to reduce cold start emissions have resulted in very marginal vehicle
driveability during cold operation. Frequent stalls after cold start and during
the warmup period have been encountered. The loss in power at full throttle
is not anticipated to be large unless high EGR rates must be used at full
throttle for NO control.
x
2.2.4.2 Alternate Systems
2. 2. 4. 2. 1 Special Design Features
General Motors states that a final selection of the first-choice system cata-
lytic converter design has not been made, and that evaluations are proceeding
on improved catalyst formulations as well as other catalytic converter
designs. Among the latter are noble metal pellet and monolithic types.
2-63
-------
General Motors claims that the design of its emission control package
permits an easy switch to the monolithic type of catalytic converter if
superior emissions performance and durability indicate the desirability of
such a change.
Another possible GM alternate system utilizes a thermal reactor for some
vehicles like the Vega (4-cylinder engine). Air/fuel conditions required for
reactor operation offer the advantage of less initial release of NO , thereby
.X
requiring less aftertreatment by reducing catalyst systems planned for 1976.
2.2.4.2.2 Problem Areas and Plans for Resolution
Two major problems encountered by GM with the noble metal /monolith
catalyst converter are high deterioration rates and susceptibility to overtem-
perature and to poisoning. Improved catalyst formulations continually are
being tested and will be used if found to be superior to the first-choice system.
Problems encountered with the manifold reactor are driveability and packaging.
The need of extensive insulation to maintain high oxidizing temperatures
(1500-2000 °F) affects the problem of engine compartment packaging. More
experience in the use of high efficiency insulation materials is said to be
needed. Air requirements for the thermal reactor exceed those for the
catalytic converter; a larger air pump is therefore required. Satisfactory
materials for manifold reactor durability have not yet been found.
2.2.4.2.3 Emissions
2.2.4. 2. 3. 1 Test Programs and Vehicle Description
The test program description provided in Section 2. 2.4. 1. 3. 1 js generally
applicable to the second-choice system. General Motor's experimental exhaust
manifold reactor vehicles were a 350-CID Chevrolet and a 140-CID Vega.
2-64
-------
2.2.4.2.3.2 Test Procedure
The 1975-CVS-CH Federal Test Procedure was used. Durability data for the
GM alternate systems are not provided except for the vehicle utilizing an
Engelhard platinum/monolith catalyst converter. This system was tested on a
modified AMA test track.
2.2.4.2.3.3 Emission Data Summary
The emission data reported by GM for alternate catalytic converter systems
of the noble metal bead and monolithic designs are included in Tables 2-16
and 2-17. Additional GM data covering the performance of the noble metal/
monolithic Engelhard PTX system were reported in the Engelhard submittal
and are presented in Table 2-18. Table 2-19 provides low mileage emission
data for the exhaust manifold reactor system.
2.2.4.2.3.4 Best Emission Results
The only data for the noble metal bead-type catalyst (BN) was reported for the
UOP PZ-2-168-R-5 design. This catalyst has accumulated 2287 miles within
standards (Car 61420 in Table 2-16). High mileage data for this system was
not provided.
The Engelhard platinum/monolith converter (Car 61319 in Tables 2-16 and
2-17) shows very good low mileage emission results: 0.13, 1.9, and 1.3
gm/mi for HC, CO, and NO , respectively. The 1975 standards were
3C
exceeded for HC at 4000 miles, for CO at 5500 miles, and for NO at 6000
miles. Referring to the GM data reported by Engelhard and shown in
j .v>] : 2-18, Car 17934, described as a 455-CID 1971 Buick Estate Wagon
.juipped with two Engelhard PTX-423S monolithic converters, is indicated
o have accumulated 24,630 miles at emission levels of 0. 34, 3. 09, and
2. 54 gm/mi for HC, CO, and NO , respectively. Engelhard further reports
3C
that this system accumulated a total of 70, 000 miles, at which point the
respective emissions were 0. 85, 8. 7, and 3. 5 gm/mi.
2-65
-------
to
Table 2-18. General Motors Mileage Emission Data Reported by Engelhard
(GM Alternate Systems)
Car No.
17934
Car and CID
Buick 455
Oxidizing Catalyst
Type"1
MN
Supplie r
Engelhard
PTY.d?^
I
Svsieni Description
AIR
X
EGR
X
Mod
Carb.
X
EFE
Test
Weight
5000
Test
Date
5M4'71
6/11/71
6'22/.71
7/1J71
T/16/71
2/27/72
Car
Mileage
13,092
24.527
28,721
33,252
37,722
Catalyst
Mileage
0
11.435
15,629
20, 160
24.630
70,000
1°72-CVS-C Emissions!
l>m:;v.i
HC CO NOX
0. 12 1. 88 2. 39
0.48 3.01 2.43
0.31 3.33 2.67
0.55 3.76 2.08
0.34 3.09 2.54
0.85<2>8.7(Z' 3.5(2)
Comments
High speed tire test at ;
perature during
emission run 1230°F -
After completion of
70.000 mi. tested on AC
Test Car 067 at Detroit
"'Type: MN = monolith/platinum (0. 2'.)
1975-CVS-CH test procedure: average of 2 tests.
Table 2-19. Exhaust Manifold Reactor System Vehicles (GM Alternate Systems)
Car
Chev.
Vega
Vega
Chev.
Chev.
Engine
CID
350
140
140
350
350
Emissions, gm/mi*
HC CO NO
x
0.1 3.9 0.8
0.2 2.8 0.39
0.24 3.0 0.39
0.28 1.1 0.6
0.1 1.2 1,2
System Description
Glass insulated, Air, EGR
Sand insulated, Air, EGR
Sand insulated, Air, EGR
Reducing catalyst converter, Air, EGR
(1976 System)
Reducing catalyst converter, Air, EGR
(1976 System)
"1975 CVS-CH Procedure
-------
Best low mileage emissions for the exhaust manifold reactor -system
(without reducing catalyst) were 0. 2, 2. 8, and 3. 9 gm/mi for HG^CO, and
NO , respectively. No high mileage emissions for the. exhaust manifold
?c
reactor system were provided.
2.2.4.2.3.5 Test Data Variability
The available data do not permit a statement to be mdde concerning test data
variability. Variations are expected to be. of the; same, order of magnitude
as described for the GM first-choice system in Section 2.2.4: 1.3. 5.
2.2.4.2^.4 Fuel Consumption and Performance Penalties
The second-choice catalytic converter system is expected to change the fuel
consumption and affect performance to the same degree reported for the first-
choice system in 2.2.4. 1.4. In the case of the exhaust reactor manifold
system, the fuel consumption penalty is expected to be more severe because
the engine must be operated with rich air/fuel ratios to sustain efficient
reactor operation. Operation at high EQR to Deduce NO seriously deteriorates
vehicle performance. Compared to the current production vehicle, the Vega
manifold reactor system shows a 50 percent increase in the time required to
accelerate from 0 to 60 mph.
2. 2. 5 International Harvester
2. 2. 5. 1 First-Choice Systems
2.2.5.1.1 . Special Design Features
The system presently envisaged by International Harveste.r as a first-choice
selection would consist of an oxidizing catalytic converter, advanced EGR, and
engine modifications, including advanced carburetion and a quick heat manifold.
The advanced EGR system utilizes EGR rate/load proportioning calibrations
as well as venturi signal proportional amplifiers. Neither the advanced EGR
nor advanced fuel systems are yet available in the form of production proto-
types; therefore, modifications to current hardware are being used (Refs.
2-16, -17) on all test vehicles for these items.
2-67
-------
The selection of a specific catalytic converter has not yet been ma.de by
International Harvester. Primary effort to date has concentrated on an AC-
Delco base metal/pelletized catalyst packaged by the Walker Manufacturing
Company, and an Engelhard noble metal monolithic catalyst, also packaged
by Walker. International Harvester does not plan to manufacture the catalyst
container but rather will procure it from an outside vendor.
2.,2. 5. 1.2 Problem Areas and Plans for Resolution
International Harvester has not yet met the 1975 emission standards, even
with zero mile vehicles. This is attributed to the low horsepower-to-weight
ratio of the International Harvester vehicles which results in high average
engine load factors with resulting high exhaust gas temperatures. Progress
in limiting maximum gas temperature entering the catalyst, while still main-
taining adequate chemical energy input during lighter load phases, has resulted
in increased cold start emissions.
2.2.5.1.3 Emissions
2. 2. 5. 1. 3. 1 Test Programs and Vehicle Description
International Harvester is continuing the evaluation of emission control
systems as components become available. New catalytic converters are
undergoing test as they are received from outside vendors. A Matthey Bishop
noble/metal catalyst on a Corning extruded monolithic substrate is one of the
confii urations being examined. Test results from this converter are not
reported. All high mileage emission data reported for the first-choice system
have been accumulated on the 5500-lb inertia weight Travelall vehicles,
equipped with either the AC-Delco base metal/pelletized converter, the
Engelhard noble metal/monolithic (stacked) converter, or the W.R. Grace
noble metal/monolithic (spiral wound) converter. All high mileage data have
been accumulated in accordance with the AMA durability schedule.
2.2.5.1.3.2 Test Procedures
Test data reported by International Harvester conform to the 1975 CVS-CH
test procedure.
2-68
-------
2.2.5.1.3.3 Emission Data Summary
First-choice system low mileage emission data reported by International
Harvester (Reference 2-16) was designated as a range of "representative"
emission levels as follows:
International Harvester First-Choice System--
"Representative " Emission Levels
HC 0.3-0.5 gm/mi
CO 4. 5 - 8.8 gm/mi
NO 2.4 - 3. 1 gm/mi
X.
AMA durability (high mileage) test results are reported for tests conducted
on two different 5500-lb inertia weight vehicles as shown in Table 2-20. In
no case has the 1975 standard for CO been achieved.
2.2.5.1.3.4 Best Emission Results
The best emission results reported by International Harvester for their first-
choice system were achieved at zero miles on Travelall Vehicle #1 shown in
Table 2-20. These were 0.35 gm/mi HC, 4.5 gm/mi CO, and 2.5 gm/mi
NO .
x
2.2.5.1.3.5 Test Data Variability
The material presented by International Harvester does not permit a statement
concerning data variability to be made.
2. 2. 5. 1.4 Fuel Consumption and Performance Penalties
International Harvester estimates that the fuel economy for 1975 vehicles will
be 10-15 percent below that of the 1972 vehicles (Ref. 2-16). To offset the
anticipated loss in vehicle driveability and power, an increase in engine dis-
3
placement of approximately 80 in. is estimated to be required. New engines
are in the development stage and are scheduled for production in the 1975 model
year vehicles.
2-69
-------
Table 2-20. High Mileage Emission Results International Harvester First-Choice System
i
-«J
o
Vehicle ;
.Travelall #1 392 CID
Manual Transmission
Travelall #2 392 CID
Automatic Transmis-
sion
Miles
0
4000
8000
12000
16000
0
4000
8000
12000
0
4000
8000
12000
16000
20000
Emissions, gm/mi
HC CO NO
X
0.45 4.4 3.0
0.46 10.4 4.2
0.77 12.7 2.3
0.83 12.4 2.5
0.83 11.4 2.6
0.35 4.5 2.5
0.63 8.8 2.4
0.63 10.3 2.5
0.68 9.2 2.3
0.35 4.6 3.1
0.33 4.7
0.49 5.7 2.5
0.53 7.5 3.6
0.69 11.7 4.7
0.51 8.8 3.0
Remarks
AC-Delco base metal converter
Inadvertent use of leaded fuel
suspected
Engine tuned, converter recharged
Test Continuing
AC-Delco base metal converter
O*
""1975 CVS-CH test procedure
-------
2. 2. 5. 2 Alternate Systems
2. 2. 5. 2. 1 Special Design Features
The system being evaluated by International Harvester on a second-choice
basis consists of a thermal reactor, EGR, and an advanced fuel system with
a fast heat manifold. Although the degree of control of HC and CO has not
been at all satisfactory to date, it is the opinion of International Harvester
that the thermal reactor represents a reliable system which is more suitable
to the heavy duty nature of its product.
An additional system being developed in a parallel program involves a
combination of the first- and second-choice systems; i.e., catalytic conver-
ter, thermal reactor, EGR, air injection, and engine modifications.
2.2.5.2.2 Problem Areas
Problems related to the International Harvester alternate systems were not
discussed in specific terms. Extremely poor CO control with the thermal
reactor system has been encountered, along with poor performance, drive-
ability, emission control durability, and fuel economy. As is the case with
the first-choice system, International Harvester is experiencing a great
deal of difficulty in achieving the 1975 CO standards.
2.2.5.2.3 Emissions
2. 2. 5. 2. 3. 1 Test Programs and Vehicle Description
All data reported for International Harvester are based on the 1975 CVS-CH
test procedure unless otherwise indicated.
2-71
-------
2. 2. 5. 2. 3. 2 Emission Data Summary
Low mileage emission data reported by International Harvester for their
second-choice system were designated in Ref. ,2-16 as a range of
"representative" emission levels as follows:
International Harvester Second-Choice System--
"Representative" Emission Levels
HC 0.37 - 1. 0 gm/mi
CO 14.8 - 22.3 gm/mi
NO 1.2 - 2.8 gm/mi
Ji
High mileage emission data were reported for two Travelall vehicles equipped
with the thermal reactor/EGR second-choice system. These data are shown
in Table 2-21. Vehicle 257, which had no overtemperature protection device,
was tested with 5 percent EGR. The reactor core was fabricated from 185R
chrome aluminum alloy. The thermal reactors were removed for inspection
at 24, 000 miles. The left reactor core runners were found to be eroded and
the core assembly severely warped. High underhood temperatures resulted
in premature ignition wire failures. Vehicle 399 was tested with 8 percent
EGR. This vehicle was equipped with an overtemperature protection system.
Test data were not reported at intermediate mileage points for this vehicle.
Reactor casting life was reported as unacceptable; cracking was observed at
2000-1000 miles.
Only limited emission data are available for the International Harvester
second alternate system (thermal reactor, catalytic converter, EGR, air
injection and engine modifications). "Representative" emission levels were
reported to be 0. 63 gm/mi HC, 3. 5 gm/mi CO, and 0. 77 gm/mi NO . No
X.
details regarding test mileage, converter type, or other specific information
were provided.
2-72
-------
Table 2-21. High Mileage Emission Data International Harvester Second-Choice System
Vehicle
Travelall #257
Travelall #399
Miles
0
4,000
8,000
1Z,000
16,000
20,000
20, 000
24,000
0
25,794
Emissions
gin/mi*
HC CO NO
X
0.41 22.3 1.78
0.66 22.8 2.20
1.42 18.9 2.83
0.52 21.7 2.81
0.37 15.7 2.76
4.84 86.2 1.27
0. 70 14. 0 2. 65
1.07 21. 1 1. 96
0.56 14.8 1.98
1.75 42.3 1.53
Remarks
5% EGR, 1972 distributor
Engine miss -fire noted
Recheck with new spark plugs and ignition wires,
carburetor cleaned.
'Miss -fire detected on first part of test.
8% EGR
V1975 CVS-CH test procedure
tv)
^1
oo
-------
2.2.5.2.3.3 Best Emission Results
The best emission results reported by International Harvester for its
alternate systems may be summarized-as follows:
International Harvester Alternate Systems --
Best Emission Results
Emissions, gm/mi
System Miles HC CO N°x
EGR + AI + TR 16,000 0.37 15.7 2.76
EM + EGR + AI + TR + OC Not specified . 0.63 3.5 0.77
2.2.5.2.3.4 Test Data Variability
No statement concerning test data variability can be made.
2.2. 5.2.4 Fuel Consumption and Performance Penalties
Fuel consumption and performance penalties for the alternate
International Harvester systems are not discussed.
2-74
-------
2. 2. 6 Alfa Romeo
2.2. 6. 1 First-Choice System
2. 2. 6. 1. 1 Special Design Features
Alfa Romeo did not identify a candidate 1975 system (Ref. 2-18). Test results
reported by UOP (Ref. 2-19) for a 4-cylinder 2.0 liter overhead cam engine
3
equipped with a 60 in PZ-216 UOP catalyst were 0.44, 2.69, and 1.83 gm/mi
for HC, CO, and NO respectively, by 1975 CVS-CH procedures (averages of
two tests). Mileage associated with these results was not specified.
2.2.7 BMW
2.2.7.1 First-Choice System
2. 2. 7. 1. 1 Special Design Features
The 1975 system projected for use by BMW will consist of engine modifica-
tions, EGR, air injection, and an oxidation catalyst. The lowest emission
data obtained, but not reported, approximate the 1975 standards (Ref. 2-18).
2.2. 8 British Leyland Motor Corporation
2.2.8. 1 First-Choice System
2. 2. 8. 1. 1 Special Design Features
British Leyland states that it is impracticable and uneconomical to select a
system suitable only for 1975; accordingly, it has made a major effort to
develop a 1975 emission control package which, with the add-on of a reducing
catalyst, would also serve for use in 1976 (Refs. 2-20, -21, -22).
The British Leyland first-choice system for 1975 comprises'an oxidizing
catalytic converter (type not selected, but probably a platinum monolith),
secondary air injection, and engine modifications. Thermal reactors have
been rejected as being unable to meet the 1976 standards and were not needed
for the 1975 standards. Exhaust gas recirculation (EGR) will not be used on
most models (possible exceptions include the Jaguar). The 1975 NO standard
2-75
-------
is being met with ignition timing retardation and by reducing engine
compression ratio to 8:1.
British Leyland has contracted with Imperial Chemical Industries (ICI) for
technical support in the development of suitable catalytic converter designs.
British Leyland plans to produce its own converter hardware. Both mono-
lithic and granular catalytic converter designs are being evaluated.
2.2.8.1.2 Problem Areas and Plans for Resolution
V a
Durability is a problem both for the engine and the catalyst. Valve recession
resulting from use of unleaded fuel has been difficult to cure, especially in
the smaller engines where there is little room for valve inserts. Mechanical
failure of the granular catalyst container, which results in the loss of catalyst
particulates, is a problem which has not yet been solved. Another problem
is catalyst poisoning due to fuel and oil contaminants. This problem is par-
ticularly difficult because the local fuel contains different amounts of sulfur
and other contaminants than in the U.S. British Leyland finds it impossible
to say when, or even if, a solution can be found to the problems of catalyst
poisoning, attrition, or mechanical failure.
Installation of the converter has presented packaging problems because of its
size and the heat generated and emitted to the local environment. In addition,
expansion between the metallic case and the ceramic core of the monolithic
converter design is a problem yet to be overcome. Data developed to date
strongly suggest that British Leyland catalysts will have to be replaced at
intermediate mileage points in order to maintain emission control for
50, 000 miles.
British Leyland does not believe that any of the problems are insurmount-
able, but they feel they are running out of time to develop a satisfactory
50, 000-mile catalytic converter.-
2-76
-------
2.2.8.1.3 Emissions
2. 2. 8. 1. 3. 1 Test Programs and Vehicle Description
Tests have been carried out on the following vehicles:
Austin Marina
MGB
Triumph GT6
Triumph Spitfire
Triumph TR-6
Jaguar XJ6
The gasoline used for testing has 0. 014 gm/gal of lead at 91 octane. British
Ley-land believes that the EPA specification for gasoline lead content will
ultimately be lov.-er than the 0. 05 gm/gal value currently projected for unleaded
fuel. Consequently they have not yet attempted to study the effect of higher
lead content on catalyst performance.
No mention is made of test conditions, or the number of cars involved in
British Leyland's test program.
2.2.8.1.3.2 Test Procedures
The 1975 Federal Test Procedures are being used for all tests. The driving
cycle for mileage accumulation was not specified.
2.2.8.1.3.3 Emission Data Summary
Emission data are shown in Table 2-22 for low mileage emissions and in
Table 2-23 for high mileage emissions. Some of the catalysts were identified
during the EPA hearing and these are designated in the tables.
2.2.8.1.3.4 Best Emission Results
The best (low mileage) emission results were obtained with a 110-CID Austin
Marina equipped with an Engelhard PTX monolithic catalyst. Emission levels
2-77
-------
Table 2-22. British Leyland Low Mileage Emissions
Type/
Car Engine CID Weight, Ib Mileage
Austin 110 Saloon 0
2500
Austin 110 Saloon 0
2500 4000
Austin 110 Saloon 0
2500
Austin 110 Saloon 0
2500
MGB 110 Sports 0
3000
Triumph GT6 113 Saloon 0
2500
Triumph Spitfire 80 Sports 0
2000
Triumph TR-6 152 Sports 0
2750
Jaguar XJ-6 258 Saloon 0
4000 4100
Jaguar XJ-6 258 Saloon 0
4000
*
Emissions, gm/mi
HC CO N°x
0.11 1.78 1.86
0.04 1.49 1.67
0.10 0.92 2.27
0.18 2.29 2.33
0.19 1.38 2.08
0.14 1.02 2.41
0.58 1.78 2.04
0.50 1.95 1.87
0.39 5.10 1.75
0.08 2.80 0.86
0.15 3.00 1.10
0.20 2.50 1.00
Oxidizer Catalyst
Engelhard PTX (Pt/monolith)
Engelhard PTX (Pt/monolith)
ICI noble metal/monolith
ICI noble metal/granular
Johnson-Matthey noble metal
Engelhard PTX (Pt/monolith)
Engelhard PTX (Pt/monolith)
Engelhard PTX (Pt/monolith)
Engelhard PTX (Pt/monolith)
Johnson-Matthey noble metal
Comments
Stacked monolith
Stacked monolith
With EGR
Without EGR
*1975 CVS-CH test procedure
ts)
I
-J
00
-------
Table 2-23. British Leyland High Mileage Emissions
Car
Austin
Austin
Austin
Engine CID
110
110
110
Type/
Weight, Ib
Saloon
2500
Saloon
Z500
Saloon
2500
Mileage
0
11400
11450
17000
0
6574
9200
13000
0
4500
5800
Emissions/gm/mi
HC CO N°x
0.11 1.78 1.86
0.28 2.73 2.32
0.34 2.08 1.65
0.63 4.65 1.32
0.18 2.29 2.33
0.45 3.00 1.97
0.20 2.61 2.21
No data provided
0.19 1.38 2.08
0.25 1.14 2.44
No data provided
Oxidizer Catalyst
Engelhard PTX (Pt/monolith)
ICI noble metal/monolith
ICI noble metal/granular
Comments
Stacked monolith
Valve recession
New head on engine
Catalyst was sent back
to supplier
Test in progress
Slight catalyst
deterioration
* 1975 CVS-CH test procedure
-------
were 0. 04 gm/mi HC, 1. 49 gm/mi CO, 1. 67 gm/mi NO . After 4000 miles
the emission levels were still within standards at 0. 1-0 gm/mi, 0. 92 gm/mi,
and 2. 27 gm/mi. Best high mileage results were achieved with the Austin
vehicle also using an Engelhard PTX catalyst; 11,450 miles were accumulated
with emissions still within standards at 0. 34 gm/mi HC, 2. 08 gm/mi CO,
1. 65 gm/mi NO . The plotted results indicate that HC exceeded the standard
at 12, 000 miles. The maximum mileage accumulated on this system was
17, 000 miles.
2.2.8.1.3.5 Test Data Variability
In answering questions from the Ford Motor Company, British Leyland stated
that the day-to-day repeatibility of data on one car is ± 15 percent. The
spread of results with mileage and on different examples of nominally identi-
cal vehicles has not yet been determined.
2.2.8. 1.4 Fuel Consumption and Performance Penalties
British Leyland states that the difference between a 1975 car marketed for
the U. S. and one for the home market will be a 13 percent increase in fuel
consumption coupled with reduced performance of about 10 percent.
Driveability will be slightly improved compared with 1972/73 models because
of the use of richer air/fuel ratios. However, driveability will be worsened
during the warmup period. Expected fuel consumption for a 1975 vehicle
with a 110-CID engine is 28. 7 mi/gal.
2. 2. 8. 2 Alternate Systems
2. 2. 8. 2. 1 Special Design Features
Every effort is being made to dispense with EGR on all models. The alternate
system would incorporate EGR on some models, including the Jaguar. In
addition, it may be necessary to add a catalyst overtemperature protection
system.
2-80
-------
2. 2. 8. 2. 2 Problem Areas and Plans for Resolution
No problems with the EGR and the catalyst by-pass system are defined.
2. 2. 8. 2. 3 Emissions
The 1975-CVS-CH Federal test procedure is used. The duty cycle for mile-
age accumulation was not specified. The test vehicle was a Jaguar XJ6.
Emission results obtained with and without EGR are shown in Table 2-22.
The maximum mileage accumulated was 4100 miles with HC - 0. 15 gm/mi,
CO = 3.0 gm/mi, and NO =1.10 gm/mi. No information on test data
j£.
variability specific to the alternate system is provided.
2. 2. 8. 2. 4 Fuel Consumption and Performance Penalties
British Leyland believes that better driveability is achieved without EGR. No
further information on fuel consumption or performance is given.
2. 2. 9 Citroen
2. 2. 9. 1 First-Choice System
2.2.9. 1. 1 Special Design Features
Citroen did not identify a candidate 1975 system (Ref. 2-18).
2.2.10 Daimler-Benz AG (Mercedes-Benz)
2.2.10.1 First-Choice System
2.2.10.1.1 Special Design Features
A first-choice 1975 emission control system is identified separately for the
Mercedes-Benz vehicles equipped with a gasoline engine and for vehicles
equipped with a diesel engine (Refs. 2-23, -24, -25).
2.2.10.1.1.1 Gasoline Engine
Mercedes-Benz vehicle equipped with a gasoline engine is projected to use
the following subsystems in 1975:
Noble metal /monolith oxidation catalyst converter
Secondary air injection
2-81
-------
Exhaust gas recirculation (EGR)
Engine modifications
Carburetor or fuel injection system changes
Retarded ignition and short c-h'dke operation
Reduced compression ratio (8:1)
Warmup of intake air
The bulk of promising low emission levels data has been obtained on
dynamometer testing with Engelhard PTX-4 noble metal/monolith catalytic
converters. Some good results have also been obtained with Matthey Bishop,
Kali-Chemie, and Degussa catalysts.
2.2.10.1.1.2 Diesel Engine
The Mercedes-Benz vehicle equipped with a light duty 4-cylinder diesel
engine of the 2.2-liter class is likely to meet the 1975 Federal emission
standards for HC, CO, and NO . However this is contingent upon the
promulgation of emission standards and test procedures applicable to diesel
engine vehicles. Only minor modifications to the fuel injection system will
be required provided the restrictions on exhaust smoke arid particulate con-
tent are not unduly severe.
2.2.10.1.2 Problem Areas and Plans for Resolution
2. 2. 10. 1. 2. 1 Gasoline Engine
According to Daimler-Benz, the success of its entire emission control
system hinges on the development of a successful oxidizing catalytic con-
verter. New catalyst formulations are tested on engine dynamometers as
soon as received. The major problems with the catalytic converters are
insufficient mechanical durability and high deterioration of conversion
efficiency. Daimler-Benz is very pessimistic about the resolution of the
catalyst deterioration problem and does not expect any technological
breakthrough in this area.
2-82
-------
2.2.10.1.2.2 Diesel Engine
Daimler-Benz states that an EPA ruling on smoke and particulate emissions
from dies el engines is urgently needed. In addition, pollutant measurement
techniques applicable to diesel engines must be defined.
Daimler-Benz believes it will be able to meet the 1975 Federal standards
with its light duty diesel engine by simple modifications to the fuel injection
system. However, it cautions that this will no longer be true if severe
smoke and particulate controls are instituted. This is a particular problem
during cold start. Daimler-Benz has achieved low levels of smoke and
particulate emissions (less than 1 gm/mi). Further reduction might force a
change in the engine combustion characteristics which could increase the
other pollutant levels.
2.2.10.1.3 Emissions
2. 2. 10. 1. 3. 1 Test Programs and Vehicle Description
The bulk of Daimler-Benz's test program is being run on dynamometers with
engines or experimental cars. As long as 50,000-mile durability cannot be
successfully completed on engine dynamometers, Daimler-Benz sees no need
for committing cars to road testing. Oxidizing catalytic converters are tested
on the 2.2-liter (134 CID) 4-cylinder engines used on Mercedes-Benz (MB)
220 vehicles, on the 2.8-liter, 6-cylinder engines with fuel injection used on
MB 250 vehicles, and on the 4. 5-liter (276 CID) V-8 engines with fuel injec-
tion used on MB 280 vehicles.
The experimental vehicles are as follows:
MB 220 V-25 (3500 Ib) mechanical shift
MB 220 VL-5 (3500 Ib) mechanical shift
MB 250 (3500 Ib) automatic shift
MB 250 CE (3500 Ib) automatic shift
MB 250 CE (4000 Ib) automatic shift
2-83
-------
MB 280 (4000 Ib) automatic shift
MB 450 (4000 Ib) automatic shift
MB W108 (4000 Ib) automatic shift
*'
No information is provided on the diesel test program.
2.2.10.1.3.2 Test Procedures
All emission level measurements on gasoline engines reported by Daimler-
Benz were made using the 1975'-CVS-CH Federal Test Procedure (Table
2-24). Diesel engine test procedures are not defined.
Catalytic converter durability tests are reported in Table 2-25. Those tests
with both hours and miles shown were run on engine dynamometers using the
Mercedes W3 test schedule (mild driving conditions) as follows:
Duration, hr RPM Load
1/4 idle
1/2 2000 1/2
1/2 3000 1/2
1/4 idle
1/4 3000 full
1/2 4000 1/3
2 1/4
The systems in Table 2-25 with only mileage shown were road tested in an
unspecified manner. The gasoline used for test contains less than 0. 01 gm/
gal of lead and less than 0. 03 percent of sulfur.
2. 2. 10. 1. 3. 3 Emission Data Summary
2.2.10.1.3.3.1 Gasoline Engines
The low mileage emission results obtained recently by Daimler-Benz are
listed in Table 2-24. The majority of catalyst converters shown were
manufactured by Engelhard (platinum/monolith). Sixty percent of the test
2-84
-------
Table 2-24. Daimler-Benz Low Mileage Emissions
Test
Date
12-9-71
12-10-71
12-16-71
1-31-72
10-27-71
10-29-71
11-3-71
11-4-71
11-11-71
11-11-71
11-12-71
11-12-71
11-15-71
11-10-71
11-10-71
11-16-71
11-18-71
11-24-71
12-8-71
12-9-71
12-10-71
Test
Number
1778
1788
1818
2032
1579
1591
1574
1611
1632
1636
1639
1640
1644
1655
1657
1679
1683
1710
1770
1780
1791
Car
Model
220V25
220V25
220V25
220VL5
250CE
250
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250
Vehicle
Mass, Ib
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
4000
4000
4000
3500
4000
3500
Emissions, gm/mi''"
HC
0. 38
0.25
0.41
0.23
0.75
0.24
0.30
0.36
0.51
0.22
0.35
0.27
0.36
0. 51
0.45
0.73
0.35
0. 56
0.36
0. 34
0. 30
CO
3.48
2.04
8. 19
2.84
5.43
1.85
1. 57
1.74
1. 13
1.85
2.09
2.69
2.69
3.69
1.83
1.73
3.50
4.39
3.06
3.52
3.04
NO
X
0.61
0.72
0.61
0.44
1.16
1.69
1.84
1.97
1.72
1.94
2. 15
1. 27
2.01
1.65
1.55
1.82
2.16
2. 12
1.82
2.20
1.89
Oxidizer Catalyst
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard
PTX-4.
4.5
2 PTX-4, PTX-5
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
PTX-4.
2 PTX-
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4, PTX-5
-------
Table 2-24. Daimler-Benz Low Mileage Emissions (Continued)
Test
Date
12-14-71
12-17-71
1-24-72
1-26-72
3-6-72
12-14-71
1-4-71
1-7-72
1-10-72
1-27-72
1-27-72
2-2-72
2-3-72
2-8-72
2-9-72
2-10-72
2-11-72
2-16-72
2-15-72
2-18-72
2-25-72
Test
Number
1805
1827
1997
2015
2208
1807
1873
1911
1912
2012
2020
2028
2057
2072
2076
2079
2084'
2085
2099
2110
2151
Car
Model
250
250CE
250CE
280
250CE
W108
W108
450
450
W108
W108
W108
W108
W108
W108
W108
W108
W108
W108
W108
W108
Vehicle
Mass, Ib
3500
4000
4000
4000
4000
4000
4000
4000
4000
4000
4000
4000
40.00
4000
4000
4000
4000
4000
4000
4000
4000
Emissions,
HC
0.33
0.33
0.31
0.68
0.33
0.47
0. 35
0. 20
0.31
0.40
0.48
0. 11
0.13
0.17
0.22
0. 16
0.19
0.12
0.14
0.13
0.22
CO
3. 18
3. 16
3. 99
7.21
7.66
3.99
4. 3Z
3.37
4. 09
3.62
1.49
3.42
2. 08
2.41
2.81
1. 88
1.90
. 2. 35
2.87
2.45
3.81
gm/mi
NO
X
1.36
1.88
2.97
2.24
2.95
1.60
1. 75
2.05
2.08
2.34
2.59
1.91
1.82
1.70
1.61
1.57
1.23
1.19
1. 18
1.35
l._17
Oxidizer Catalyst
Engelhard 2 PTX-4, PTX-5
Engelhard PTX-4. 4. 5
Engelhard PTX-4. 4. 5
Engelhard PTX-4. 4. 5
Engelhard PTX-4. 4. 5
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Engelhard
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Engelhard
Engelhard 4 PTX-4
Engelhard 4 PTX-4"
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Engelhard
ro
i
00
-------
Table 2-24. Daimler-Benz Low Mileage Emissions (Continued)
Test
Date
2-29-72
3-3-72
3-7-72
3-13-72
3-16-72
3-17-72
-
-
Test
Number
2180
2197
2204
2245
2258
2264
2324
2377
*1975 CVS-CH test
Car
Model
W108
W108
W108
W108
W108
W108
-
-
procedure
Vehicle
Mass, Ib
4000
4000
4000
4000
4000
4000
-
-
Emissions,
HC
0. 11
0. 13
0. 10
0. 13
0. 10
0.15
0. 10
0.14
CO
2.34
5.56
3.17
2.67
1.47
1.72
1.70
2.3
gm/mi'"
NO
X
1. 14
0.97
1.44
0. 81
1. 14
0. 88
0. 28
1.0
Oxidizer Catalyst
Matthey Bishop
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Matthey Bishop
Matthey Bishop
Matthey Bishop
Kali-Chemie
Degussa
i
oo
-------
Table 2-25. Daimler-Benz Catalyst Durability Tests
Company
Engelhard
1. PTX
2. PTX
3. PTX
4. PTX
5. PTX
6. PTX
7. PTX
8. PTX
9. PTX
10. PTX
11. PTX
12. PTX
13. PTX
Kali-Chemie
14. KG
15. KG
16. KG
17. KG
18. KG
19. KG
20. KG
Heraeus
21. H
22. H
23. H
24. H
Grace
25. G
Degussa
26. Dl
APC-Ceraver
27. APC
28. APC
Matthey Bishop
29. Ml
300 M
31. M
32. M
33. M
34. M
Serial No.
1212 638
1212 4461
1212 446F
1212 564
1212 425D
1212 446 A
1212 446B
1212 446C
1212 446D
1212 446E
1212 212L
1212 429B
1212 429C
101/4035
103/4035
1/3368
2/3368
3/3368
4/3368
5/3368
101/250
102/250
101/350
102/350
1
506E
1 RC6226
2 RC6226
1/3A
S/3A
9/3A
10/3A
11/3A
101/350/3A
Hours
330
140
60
30
45
4
50
50
50
55
(a)
51
65
54
32
18
(a)
(a)
(a) '
(a)
17
12
23
34
14
32
72
72
63
(a)
(a)
(a)
(a)
4
Miles
15500
6600
2820
1410
2100
188
2350
2350
2350
2580
1200
2390
3050
2530
1500
845
1300
1300
1300
1300
800
565
1080
1600
660
1500
3380
3380
2950
3700
3700
3700
3700
188
Status
Defective
Defective
Defective
Defective
Defective
Defective
Running
Running
Running
Running
Running
Running
Running
Defective
Defective
Defective
Running
Defective
Running
Running
Defective
Defective
Defective
Defective
Running
Defective
Defective
Defective
Defective
Defective
Defective
Running
Running
Defective
(a) = Road test
2-88
-------
data listed are within the 1975 Federal emission standards. Vehicles and
emission levels pertinent to the mileage accumulation data shown in
Table 2-25 were not specified.
2. 2. 10. 1. 3. 3. 2 Diesel Engines
Tests of the 220D (diesel) and 220 gasoline powered Mercedes automobiles
(1972 procedure) revealed that the diesel produces about 30 percent as much
HC, 5 percent as much CO, and 50 percent as much NO as the gasoline 220.
Based on PHS odor rating and opacity smokemeter measurements, it was
found that under certain driving conditions the odor was "as intense as old
style injector-equipped city buses." The smoke opacity rating was on the
order of 10 percent.
Table 2-26 gives emission results obtained with a single car. All emission
levels are within standards as measured by the 1972 CVS procedure using a
heated FID instrument for the HC. Daimler-Benz stated that the diesel
emission levels should not deteriorate significantly with accumulated mileage.
2.2.10.1.3.4 Best Emission Results
2.2.10.1.3.4.1 Gasoline Engine
The best (low mileage) emission results shown were obtained in Test #2324
with a Kali-Chemie catalyst: HC = 0. 10 gm/mi, CO = 1. 70 gm/mi, and
NO = 0.28 gm/mi. The highest accumulated mileage shown in Table 2-25 is
5C
15, 500 miles and was obtained on an engine dynamometer with an Engelhard
PTX catalyst converter. This test was terminated when some axial displace-
ment of the substrate was noted. The type of catalyst converter which
appears the most promising to date will be road tested as soon as more units
are received from Engelhard Industries.
2.2.10.1.3.4.2 Diesel Engine
From Table 2-26, the best results shown are: HC = 0.26 gm/mi (CVS-
continuous), CO = 1.55 gm/mi, and NO = 1.09 gm/mi.
2-89
-------
Table 2-26. Mercedes 220 Diesel 1972 Federal Test Results
J
Emissions, gm/mi
HC, SwRI FIA Heated3
CVS Bag
CVS Continuous
HC, Beckman FIAC
CVS Bag
CVS Continuous
CO, NDIR
NO NDIR
(as NO) Electrochem
Chemilum6
NOX Saltzman
(as NOp) Chemilum
Formaldehyde
Aliphatic Aldehydes
(as formaldehyde)
Acrolein
1
5/28/71
0.25
0.86
0. 27
0.28
i
1. 62
0.47
0. 73
1. 28
0. 014
0. 022
0. 012
a Heated lines and analyzer at 375 F
Run
2
6/1/71
0.26
0.82
0.27
0.38
1.61
0.59
1.07
1.J4
0.018
0.018
0. 010
Number and
- 3
6/2/71
0. 31
0. 92
0. 23
0. 30
1. 60
0.47
0. 29
1.46
0. 009
0.016
0. 019
Date
4
6/3/71
0. 25
0. 71
0. 18
0. 26
1. 55
0.46
0. 33
1. 09
0.018
0. 025
0. 019
5
6/4/71
0.36
1. 06
0. 18
0.23
1. 73
0.39
0.33
1.22
0.018
0.020
0. 013
Average
0.
0.
0.
0.
1.
0.
0.
0.
1.
1.
0.
0.
0.
29
87
22
29
62
47
55
42
27
83
015
020
015
b Entire 23-min run hand-integrated on 1-sec intervals.
c Model 400 heated analyzer at 100°F
d Envirometrics Faristor.
e Single run made 6/14/71 with new Thermo
Note: The diesel is not covered by the
Electron Instrument.
1972 Light-Duty Procedure.
2-90
-------
2.2. 10. 1.3. 5 Test Data Variability -- Gasoline Engines
Daimler-Benz reported that the spread of test results over the last six
months using the first-choice system on MB 220 vehicles is as follows:
HC CO NO..
Spread, gm/mi 0.23 - 0.41 2.04 - 8.19 0.44 - 0.72
Spread, % ±29 ±65 ±24
Average, gm/mi 0.31 4.70 0.59
2.2.10.2 Alternate Systems
2. 2. 10. 2.1 Special Design Features
If improved pellet noble metal catalysts are shown to be capable of better
durability than the monolithic noble metal catalysts they will be used for the
1975 model year vehicle. Daimler Benz has not yet tested these alternate
systems.
If the possibility of fire resulting from catalyst overtemperature is shown to
be a real danger, a safety subsystem will be added. Daimler-Benz is
developing the technology to prevent possible catalyst substrate overheating
through the use of either a by-pass system or an air pump cutoff.
2.2.11 Honda Motor Co. , Ltd.
2.2. 11. 1 First-Choice Systems
2.2. 11. 1. 1 Special Design Features
The latest Honda information available is derived from Reference 2-18,
dated October 28, 1971. As of this date, a first-choice emission control
system had not yet been selected. However, the best emission results
reported were obtained with a car equipped with an oxidizing catalytic con-
verter, air injection thermal reactor (AIR), exhaust gas recirculation (EGR),
and engine modifications.
2-91
-------
2.2.11.1.2 Problem Areas and Plans for Resolution
The main problem area outlined by Honda concerns the improvement of
methods for protecting systems from overtemperature conditions which
severely reduce the durability of the emission control system.
2. 2. 11.1.3 Emissions
No details, either on test cars or on test programs are provided. Emission
level measurements were made using the 1975 CVS-CH test procedure. The
best values indicated were HC = 0. 20 gm/mi, CO = 3.0 gm/mi, and
NO = 0. 8 gm/mi. No durability test results were provided. Test data
?£
variability is not given. An increase in pollutants by a factor of two is
expected for mass-produced vehicles compared to the prototypes.
2.2. 11. 1.4 Fuel Consumption and Performance Penalties
The fuel consumption penalty for urban driving is expected to be as high as
25-30 percent. Performance penalties are mentioned with regard to decreased
driveability caused by EGR. No data are provided.
2.2. 11.2 Alternate Systems
2.2.11.2.1 Special Design Features
Removal of the thermal reactor is considered by Honda to represent an
alternate system selection. The best emission levels given for this system
are HC = 0. 20 gm/mi, CO = 4. 0 gm/mi, and NO = 1.2 gm/mi. No dura-
5t
bility test data are available. The fuel consumption penalty is not as severe
as for Honda's first-choice system: for urban driving it is 10-15 percent; for
steady-state, 12 percent.
2-92
-------
2.2. 12 Mitsubishi Motors Corporation
2.2. 12. 1 First-Choice Systems
2. 2. 12. 1. 1 Special Design Features
The data on Mitsubishi are derived from the 1971 EPA technology assessment
survey response data October 1971 (Ref. 2-26), which identifies the
Mitsubishi first-choice emission control system as follows:
Oxidation catalyst
Air injection into the exhaust system
Exhaust gas recirculation (EGR)
Engine modifications
Improved carburetor and fast choke
Modified ignition system
Efforts have been made to reduce pollutants in the cylinder discharge to the
lowest possible levels. Pollutant levels were reported as HC =1.7 gm/mi,
CO = 23. 5 gm/mi, and NO = 1.43 gm/mi (1975 CVS-CH); very little margin
x.
is said to be available for further improvement.
The selection of the oxidation catalyst has not yet been made. However, it
would appear from the comments provided that a noble metal/monolithic type
is the preferred choice.
2.2.12.1.2 Problem Areas and Plans for Resolution
The major problem area is identified as catalyst deterioration. Variation of
engine raw emissions with mileage accumulation is also a problem and so is
the durability of the secondary air pump. The actual catalyst deterioration
factor was reported as 3. 0. It is hoped that this will be reduced to 2. 0 by 1975.
2-93
-------
2.2.12.1.3 Emissions
2.2. 12. 1. 3. 1 Test Programs and Vehicle Description
The Mitsubishi test program has involved more than 30 combinations of
different catalysts and converter designs, and encompasses 50 test vehicles
(the only car exported to the USA by Mitsubishi is the Dodge Colt). Whereas
the noble metal/monolithic appears to be the favored choice, both the noble
metal/pellet and the base metal/pellet are also being tested.
2.2.12.1.3.2 Test Procedures
The emission level measurements are made by the 1975 CVS-CH test pro-
cedure and durability testing is done using the AMA driving schedule.
2. 2. 12. 1. 3. 3 Emission Data Summary
Zero mile emission levels obtained with an Engelhard PTX-5 platinum
monolith catalytic converter were reported as HC = 0. 3 gm/mi, CO = 3.1
gm/mi, and NO = 1. 9 gm/mi. At 29,000 miles the emissions were quoted
3t
as HC = 0. 6 gm/mi, CO = 6. 0 gm/mi (NOX not given). Data submitted by
UOP at the EPA Suspension Request Hearings (Ref 2-19) from an unidentified
Mitsibushi vehicle (presumed to be the Dodge Colt) show the following
results:
Emissions, gm/mi
Mileage
600
4243
7000 0.25 4.33 - (screen failure
at about 8000 miles)
2.2.12.1.3.4 Test Data Variability
Mitsubishi'states that its emission data show variations as high as ±50 percent.
It is "compelled" to make several measurements at each test point to obtain
a reliable average emission value. Mitsubishi feels that this plurality of test
HC
0. 14
0. 19
0.25
CO
2.25
2.91
4.33
NO
X
-
-
- (
2-94
-------
measurements would create a serious problem if required for all production
vehicles.
2.2. 12. 1.4 Fuel Consumption and Performance Penalties
The fuel consumption penalty for the Mitsubishi 1975 catalyst-only system is
stated by Mitsubishi to be approximately 5 percent. Engine power penalties
could be as high as 20 percent. Mitsubishi comments that driveability has
deteriorated, but hopes that further development will provide adequate driving
characteristics by production time.
2.2.12.2 Alternate Systems
2.2.12.2.1 Special Design Features
Mitsubishi has been developing a partial (rich) thermal reactor. It could be
used in addition to an oxidation catalyst in combination with rich air/fuel
mixtures to improve NO emissions. For this combination of devices, the
following emission levels were measured: HC = 0. 23 gm/mi, CO = 4. 5
gm/mi, and NO = 0. 9 gm/mi. According to Mitsubishi the fuel consumption
X
penalty for the combined system is 25 percent. No other pertinent data on
alternate systems are provided.
2. 2. 13 Nissan (Datsun)
2. 2. 13. 1 First-Choice Systems
2. 2. 13. 1. 1 Special Design Features
The Nissan (Datsun) first-choice system will consist of an HC/CO noble
monolithic catalytic converter, EGR, air injection, and engine modifications.
A noble metal monolithic catalyst was selected for use in the first-choice
system because of the excessive attrition experienced with base metal
pellet type catalysts. Although efforts are continuing to evaluate catalysts
from some 21 different worldwide sources, Nissan indicates (Ref. 2-27) it
is currently testing Engelhard and Johnson-Matthey catalysts on its
first-choice system. It was stated in Ref. 2-28 that all of the test fleet
2-95
-------
vehicles use Engelhard catalysts on a stacked substrate. This is in
contradiction to the Phase litest results (Table 2-27) which show Car B-697
equipped with a UOP noble metal catalyst. Clarification is not provided in
the Nissan references.
The reasons for the selection of the first-choice system were not discussed.
2.2.13.1.2 Problem Areas and Plans for Resolution
Nissan reports (Ref. 2-29) that the primary problems continue to be lack of
catalyst durability and deterioration of catalyst conversion efficiency. It is
proceeding with the development and evaluation of new catalysts as they
become available. Nissan is working on several methods of accomplishing
catalyst overtemperature protection including the use of an exhaust by-pass
system, secondary air cut off, and/or precise air/fuel mixture control under
differing driving conditions to reduce the overall heating load on the catalyst.
Satisfactory performance, durability, and reliability of these systems have
not yet been obtained.
In addition to overall catalyst durability, Nissan also reports driveability
problems in terms of engine stall, hesitation on rapid acceleration, and
general engine roughness due to EGR, spark retard, and quick release choke.
Evaluation tests of vehicle driveability, with 12-18 percent EGR on both the
first- and second-choice systems, rate driveability at 2 (poor) on a scale of
5 (< .-ccellent). By comparison, the 1972 model year 97.4-CID vehicle is rated
as 4 (good).
2.2.13.1.3 Emissions
2.2.13.1.3.1 Test Programs and Vehicle Descriptions
The Nissan test program has been a two-phase effort. The main purpose of
Phase I (now terminated) was to establish catalyst durability. Phase II tests,
started in February 1972, are being conducted to test the entire vehicle
concept for 1975.
2-96
-------
Table 2-27.
Nissan First-Choice System
(Phase II Test Fleet)
Car No.
B-700
B-696
B-697
EMS
Automatic quick
released choke
with fast warm-
up device,
retarded ignition
and increased
throttle opening
Same as above
Same as above
Catalyst
PTX-416 Engelhard-
American Lava
(stack type) with
secondary air
PTX-419
(stack type)
UOP Noble metal-
pellet (2.4 liter)
EGR
18%
(Intake
manifold
entry)
18%
18%
Date
2/1/73
Z/14/7Z
Z/Z4/7Z
3/Z1/72
2/19/7Z
3/11/72
3/Z3/72
2/3/72
2/26/72
3/14/72
Mileage
0
4, 000
8, 000
12, 000
16, 000
0
4, 000
8, 000
0
4, 000
8, 000
Emissions, gm/mi
HC
0. 17
0.28
0.37
-
0.50
O.Z3
0.31
0.23
Q. 14
0.31
0.31
CO
0.99
2.4
2.6
-
3. 5
0.45
0.7Z
1.2
1.4
1.8
Z.8
NO
X
0.8Z
0.71
0.85
-
0.87
0.73
1.04
0.78
0.96
0.90
1.00
Remarks
--
Adjusted idle setting;
changed spark plug and
breaker points
Skipped
--
--
--
Adjusted idle setting;
changed spark plug and
breaker points
--
--
Adjusted idle setting;
changed spark plug and
breaker points
Notes: 1. All test results based on 1975 CVS-CH test procedure.
2. All tests are still running.
-------
Phase I test vehicles were 1972 model year cars with 1.6-liter engines,
manual chokes, and an EGR system which used air cleaner entry. The
Phase I test fleet comprised 2500-lb vehicles.
Phase II test vehicles are 1975 model year concept cars with 2. 0-liter
engines, quick release automatic chokes, fast warm up devices,-and an EGR
system which uses intake manifold entry. The Phase II test fleet was
reported to comprise 3000-lb vehicles representative of a special version
incorporating unspecified safety components.
2.2.13.1.3.2 Test Procedures
Emission results reported by Nissan for the Phase I test fleet equipped with
its first-choice systems were measured in accordance with the 1972-CVS-C
test procedure. Phase II results were obtained in accordance with the 1975
CVS-CH test procedure. The driving cycle used on the mileage accumulation
tests was reported as a modified AMA durability test route (Ref. 2-27).
2.2.13.1.3.3 Emission Data
Emission data reported by Nissan (Refs. 2-28 and 2-30) for the first-choice
system are presented in Table 2-28 for the Phase I test vehicles. The cur-
rent Phase II test program results are shown in Table 2-27. Phase I tests
were terminated in September 1971, because, in the opinion of Nissan, the
emission control deterioration rates were too high. Phase II tests are con-
tinuing. It will be noted that car No. B-700 exceeded the 1975 HC/CO
standards between 8000 and 16, 000 miles.
2.2. 13. 1.3. 4 Best Emission Results
The best emission results reported by Nissan for the Phase II first-choice
system were exhibited by car No. B-696 at zero miles. These results were
0.23 gm/mi HC, 0.45 gm/mi CO, and 0.73 gm/mi NO .
2-98
-------
Table 2-28.
Nissan First-Choice System
(Phase I Test Fleet)
Car No.
B-415
(Car 1)
B-263
(Car 2)
EMS
Manual choke
Manual choke
Catalyst
PTX-416 Engelhard-
American Lava
(stack type ) with
secondary air
PTX-516 (stack type)
EGR
13% (Air
cleaner
entry)
18%
Date
6/5/71
6/25/71
7/20/71
8/26/71
9/13/71
9/27/71
6/4/71
7/12/71
7/28/71
8/20/71
9/9/71
9/21/71
Mileage
0
4,000
8. 000
12, 000
17, 000
20, 000
0
4, 000
8, 000
12, 000
17, 000
20,000
Emission Data,
gm/mi
HC
0.40
0.75
0.83
1.05
0.95
1. 13
0.661
0.77
0. 83
1.22
1.27
1.24
CO
6. 1
6 1
7.1
7.6
8.7
8.6
5.7
6.5
6.5
7.4
7.9
7.4
NO
X
0.89
1. 15
1. 16
1.14
1. 13
1.24
0.87
1. 12
1.09
1.24
1.31
1.44
Remarks
-.
Changed EGR filter
Adjusted idle mixture;
changed EGR filter
Changed spark plugs,
breaker point, and
EGR filter
Adjusted valve clear-
ance; changed EGR
filter
Stopped the test
because too high
deterioration of
emissions
--
Changed EGR filter
Changed EGR filter
Changed spark plugs,
breaker point, and
EGR filter
Adjusted valve clear-
ance; changed EGR
filter
Stopped the test because
of too high deterioration
of emissions
Note: All test results based on 1972 CVS-C test procedure.
ro
i
vD
-------
Table 2-28. Nissan First-Choice System
(Phase I Test Fleet) (Continued)
Car No.
8D-463
(Car 3)
8D-388
(Car 4)
8D-452
(Car 5)
EMS
Manual choke
Manual choke
Manual choke
Catalyst
PTX-516 (Stack type)
PTX-516 (Stack type)
PTX-416 (Stack type)
EGR
20%
18%
22%
Date
3/20/71
4/20/71
5/25/71
6/20/71
7/20/71
4/16/71
6/15/71
7/1/71
5/1/71
6/2/71
6/25/71
7/25/71
Mileage
0
4,000
8,000
12, 000
16,000
0
4, 000
8,000
0
4,000
8,000
12,000
Emission Data,
gm/mi
HC
0.30
0.30
0.31
0.41
0.45
0.35
0.44
0.65
0.55
0.55
0.58
0.73
CO
2.8
3.0
2.6
2.6
2.9
3.2
5.7
4.9
2.8
3.5
3.4
2.9
NO
X
1.05
1.08
1.04
1. 12
0.85
1.05
0.75
0.78
1.05
1. 00
0.74
0.75
Remarks
_
--
Charged air cleaner
Adjusted idle setting;
changed spark plugs
Stopped the test because
of its seriously poor
driveability (rating
of 1.5)
..
Changed air cleaner
and carburetor
Stopped the test due to
HC/CO emissions
exceeding standards
--
--
Changed air cleaner
and EGR filter
Stopped the test due to
HC emission exceeding
standard
Note: All test results based on 1972 CVS-C test procedure.
ro
i
Hk
o
o
-------
2.2.13.1.3.5 Test Data Variability
No comment on Nissan test data variability can be made.
2. 2. 13. 1.4 Fuel Consumption and Performance Penalties
Fuel consumption penalties for the Nissan first-choice system are reported
to be 5-10 percent higher than the 1972 model year vehicle. Performance
penalties were not specifically referred to other than in terms of poor
driveability as discussed in Section 2. 2. 13. 1. 2. A statement was made that
vehicle acceleration capability is impaired.
2.2.13.2 Alternate Systems
2. 2. 13.2. 1 Special Design Features
The Nissan second-choice system uses a thermal reactor in addition to the
HC/CO catalytic converter, EGR, air injection, and engine modifications
employed in the first-choice system.
2.2.13.2.2 Problem Areas
Problems associated with the Nissan second-choice system encompass those
reported for the first-choice system plus specific problems associated with
the thermal reactor. Reactor core deformation and durability continues to
be a problem as does the development of a satisfactory insulating material
which will resist both mechanical vibration and high exhaust gas temperature.
Efforts are continuing to develop an inexpensive and easily workable core
material.
2.2.13.2.3 Emissions
2.2. 13.2. 3. 1 Test Programs and Vehicle Descriptions
Test programs and vehicle descriptions for the Nissan second-choice system
are the same as discussed in Section 2. 2. 13. 1. 3. 1.
2-101
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2.2.13.2.3.2 Test Procedures
Emission results reported by Nissan for the Phase I test fleet equipped with
the second-choice system were measured in accordance with the 1972 CVS-C
test procedure. Phase II results were obtained in accordance with the 1975
CVS-CH test procedure. The driving cycle used on the mileage accumulation
tests was reported to be a modified AMA durability test route (Ref. 2-27).
2.2.13.2.3.3 Emission Data Summary
Emission data for Nissan's alternate system are given in Table 2-29 for both
the Phase I and Phase II test results. The data were presented by Nissan
only as a range of emission levels. The most notable deterioration in emis-
sion is seen to occur in the CO emissions for both the Phase I and Phase II
test vehicles: Phase I vehicles show a fourfold increase in 32, 000 miles while
the level for Phase II vehicles doubles in 8, 000 miles.
2.2.13.2.3.4 Best Emission Results
The best emission results achieved by Nissan cannot be determined from the
data reported in Table 2-29.
2.2.13.2.3.5 Test Data Variability
Test data variability was not discussed by Nissan.
2.2. 13.2.4 Fuel Consumption and Performance Penalties
The fuel economy for the Nissan second-choice system was stated to be
10-15 percent below the 1972 model year vehicle.
2.2. 14 Renault
2.2. 14. 1 First-Choice Systems
2. 2. 14. 1.1 jxpecial Design Features
Reference 2-18 identifies two Renault emission control systems. One of
these comprises an oxidizing catalytic converter, air injection and EGR; the
other system utilizes a thermal reactor with air injection.
2-102
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Table 2-29 Nissan Second-Choice System
Type
Alternative
System
Emission
Control
Package
AB
System
Main
Components
EMS
Reactor,
HC/CO
Catalyst,
EGR
Phase I Test Fleet 197Z CVS-C
Number
of
Vehicles
Tested
8
2
Mileage
0
32, 000
Emission Levels,
gm/mi
HC
0. 13
to
0.44
0. 50
to
0.75
CO
2.0
to
4. 1
11
to
13
NO
X
0. 59
to
0.78
0.75
to
1. 1
Phase 2 Test Fleet 1975 CVS-CH
Number
of
Vehicles
Tested
1
1
Mileage
0
8, 000
Emission Levels,
gm/mi
HC
0. 27
0.47
CO
1.9
3.6
NO
X
0.73
0.92
Notes: 1. Weight of vehicles tested: Phase 1 test vehicle, 2, 500 Ibj Phase 2 test vehicle, 3, 000 Ib.
2. The lowest emission values shown above were not obtained on a given vehicle, i.e., the lowest value of HC was not obtained in
combination with the lowest value of CO or NO .
X
-------
2.2. 14. 1.2
Emissions
Emission results (1975 CVS-CH) for the two control systems identified in
Reference 2-18 are as follows:
Systems
AI (+ EGR) + OC
AI + TR
Emissions, gm/mi
HC
0. 6
1. 0
AI = Air injection
EGR = Exhaust gas recirculation
CO
3.5
6.0
OC = Oxidizing catalyst
TR = Thermal reactor
NO
2. 25
1.9
No additional information on these systems was furnished.
Results of a 16, 000 mile durability test of a Renault 1. 7-liter R16 vehicle
were reported by Engelhard (Ref. 2-13). These data cannot be identified
with a particular Renault system. Test results are shown in Table 2-30.
2.2.15 Rolls-Royce Motors Limited
2. 2. 15.1 First-Choice Systems
2.2. 15. 1. 1 Special Design Features
The latest information available from Rolls-Royce was submitted in response
to the EPA technology assessment survey questionnaire and is dated
4 November. 1971 (Ref. 2-31). The system most likely to be selected for
1975 model cars comprises an oxidation catalyst, manifold air injection,
modulated EGR, and engine modifications that include a new carburetor, new
choke (AED-Automatic Enrichment Device), retarded spark, and 7. 5:1 com-
pression ratio. Transmission-controlled spark and catalyst overtemperature
protection devices may also be added. Catalytic converters using both noble
and base metal catalysts are being investigated.
2-104
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Table 2-30. Emission Data, Renault 1.7-Liter R16
(Reported by Engelhard)
Mileage
0
1, 000
1, 000
4, 000
8, 000
8, 000
8, 000
8, 000
8, 000
12, 000
12, 000
16, 000
16, 000
Emissions, gm/mi
1975 CVS-CH test
procedure
HC CO NOX
0.08 1.01 1.46
0.23 1.72 1.57
0.11 1.75 1.63
0.15 2.55 1.50
0.31 12.57 0.86
0.36 12.0 0.85
0.33 11.11 1.09
0.26 6.20 1.77
0.15 2.67 1.93
0.48 4.60 1.38
0.27 3.28 1.79
0.33 3.31 1. 50
0.31 4.51 1.87
Remarks
65 primary idle jet
70 primary idle jet
New Beach air pump
Saginaw air pump fitted
Saginaw pump relief valve restricted
Before service
After service
Check test
2-105
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2.2.15.1.2 Problem Areas and Plans for Resolution
Rolls-Royce states that, due to installation problems, at least 6 feet of exhaust
piping will separate the catalytic converters from the engine. A major
redesign of the exhaust system could reduce the separation to 4 feet, which is
the closest possible with the existing vehicle design. This remoteness results
in a long warm-up time. Other major problems are durability and overheating
of the catalytic converter, developing a reliable overtemperature protection
system, and EGR valve plugging. No details of the continuing development
effort are given. Rolls-Royce states that "only by releasing straight from
the drawing board to production, with all the risks that this entails, could
a catalytic converter system be incorporated in 1975 model cars. "
2. 2. 15. 1. 3 Emissions
No details of Rolls-Royce's emissions test program are given. The emission
data quoted are measured per the 1971 Federal test procedure. With a
Johnson-Matthey platinum/monolithic catalyst, Rolls-Royce has obtained
these emission levels: HC = 0. 18 gm/mi, CO = 2. 53 gm/mi, and NO = 4. 15
IX
gm/mi. No durability test data were provided. No information on test data
variability was submitted.
2.2.15.1.4 Fuel Consumption and Performance Penalties
Rolls-Royce estimates that a fuel consumption penalty as high as 25 percent
is possible. Driveability problems are anticipated, but the performance
penalties, including those associated with the reduction of the compression
ratio from 9:1 to 7.5:1 and the addition of EGR, are not given.
2.2.15.2 Alternate Systems
2.2.15.2.1 Special Design Features
Alternate designs of exhaust manifolds and carburetors are being pursued.
To improve mixture preparation and distribution so that extremely lean
mixtures may be used, an auxiliary small bore induction manifold with
2-106
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extreme exhaust heating is being investigated. Rolls-Royce states that
the system appears promising.
2.2.16 Saab
2.2.16.1 First-Choice System
2.2. 16. 1. 1 Special Design Features
The final selection of a first-choice system has not yet been made by Saab.
However, according to testimony presented in Reference 2-32, Saab cur-
rently favors its Concept 2 system as a possible first choice. This system
consists of the following:
a. Zenith CD2 carburetor
b. Noble metal, monolithic catalyst
c. Air injection
The selection of a specific catalytic converter has not yet been made.
Exhaust gas recirculation does not appear to be necessary to meet the 1975
Federal standards for NO . No overtemperature protection device/system
has been tested to date, although Saab feels that such a system must be
developed to adequately control emission levels.
2. 2.16. 1. 2 Problem Areas and Plans for Resolution
The most significant problem encountered by Saab has been the lack of dura-
bility of the catalyst. Deactivation of the catalyst has been caused both by
lead poisoning and by overheating due to over-rich mixtures during cold start
and retarded spark timing. Mechanical cracking of the monolithic catalyst
support has also been experienced due to what Saab believes is improper
design of the container. The design does not provide sufficient allowance for
the differences in expansion between the container and the substrate.
Development of a satisfactory catalytic converter is continuing. Saab is con-
tinuing work in-house on container design and development as well as working
2-107
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with outside vendors. It has ordered but has not yet received the
Matthey Bishop catalyst on the Corning extruded substrate.
2.2.16.1.3 Emis sions
_. !*
2.2. 16. 1. 3. 1 Test Programs and Vehicle Description
Saab is currently conducting durability tests on the first-choice system over
the Saab MAR (Mileage Accumulation Route) driving cycle, which is its
EPA-approved vehicle certification driving cycle (Ref. 2-32).
Saab has conducted two tests to date on its first-choice system (see
Table 2-31). The first test (Test No. 4) utilized an oval Matthey Bishop noble
metal catalyst and was terminated after 995 miles when inspection revealed
that the catalyst insert was loose. The unit was returned to the manufacturer.
The second test (Test 5) was conducted on the same car equipped with a
Matthey Bishop catalyst of different but undefined configuration (Ref. 2-33).
2.2.16.1.3.2 Test Procedures
All test data reported by Saab are based on the 1975 CVS-CH test procedure.
Table 2-31. Low Mileage Emission Data -- Saab First-Choice System
Test No.
4
5
Car No.
311
311
Engine
2 liter
Catalyst
Mileage
0
995
0
1200
2520
3540
Emissions, gm/mi
HC
0. 30
0.21
0.21
0.21
0.32
0. 12
CO
1. 73
1.95
2. 32
1. 76
4.67
1.27
NOX
2. 23
2. 00
1.95
2. 02
1.75
1. 07
2-108
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2.2. 16. 1. 3. 3 Emission Data Summary
Results of two Saab low mileage tests of their first-choice system are shown
in Table 2-31. As previously indicated, Test 4 was terminated at 995 miles;
Test 5 is continuing. To date, approximately 3500 miles have been accumu-
lated on this vehicle.
When questioned about the high CO results at 2520 miles in Test 5, Saab
indicated (Ref. 2-32) that no adjustments were made to the vehicle between
the 2520 and 3540 mile test points and that they knew of no reason for this
other than test-to-test variation.
No high mileage emission data -were reported for the first-choice system.
2.2.16.1.3.4 Best Emission Results
The best (low mileage) emission results reported by Saab for its first-
choice system were obtained on Test 5, Car 311 at 3540 miles. These were
0. 12 gm/mi HC, 1. 27 gm/mi CO, and 1. 07 gm/mi NO .
X.
2.2.16.1.3.5 Test Data Variability
Reference 2-33 provides the following general comment on test data
variability: Saab does not believe that the lack of reproducibility in the test
results is caused by the test procedure. No other comment is provided.
2.2. 16. 1.4 Fuel Consumption and Performance Penalties
Fuel consumption penalties are not delineated by Saab. Only a general
statement is made (Ref. 2-33) that fuel consumption will be increased due to
richer air/fuel ratio, reduced spark advance, and lower compression ratio.
Fuel consumption for Tests 4 and 5 conducted on the first-choice system was
reported to be 22 mi/gal; no baseline fuel consumption value was reported.
A 6 percent power loss was reported for Tests 4 and 5 with driveability rated
at 7 on a scale of 10. A driveability rating of 5 is defined by Saab as border-
line; a rating of 6 and higher is classified as acceptable.
2-109
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2.2.16.2 Alternate Systems
2.2. 16.2. 1 Special Design Features
The Saab second-choice system, denoted as the Concept 3 system, will
consist of the following:
a. Bosch electronic fuel injection or Zenith CD-2 carburetor
b. Base metal pellet catalyst (Saab container)
c. Air injection
d. EGR (may be deleted)
Selection of a specific base metal pclletized catalytic converter has not yet
been made, although Saab has stated that its best results to date with the
base metal catalyst have been obtained with catalysts from Kalie-Chemie and
Monsanto. A final decision has not been made with regard to the use of EGR,
although Saab expressed the opinion that it would not be necessary to meet the
1975 standards.
Other systems being studied by Saab include, the Concept 1 and Concept 4
systems. The Concept 1 system incorporates electronic fuel injection or a
Zenith carburetor, noble metal/monolithic catalyst (Engelhard), and on-off
EGR (may be deleted). Three tests have been conducted on this system;
the mileage accumulated was 1770, 4550 and 7700 miles. All three tests
were terminated when the catalyst insert came loose.
The Saab Concept 4 system, consisting of a Zenith CD2 carburetor, on-off
EGR, and a base metal pellet catalyst (vendor-supplied container) is currently
undergoing test. To date, 4180 miles have been accrued, wit.h emission levels
of 0. 39 gm/mi HC, 4. 55 gm/mi CO, and 1. 53 gm/mi NO .
J\.
In addition to the preceding, several systems which include a thermal reactor
are being investigated. In general, these thermal reactor systems have not
been effective and are being investigated only as a back-up system in the event
2-110
-------
adequate durability cannot be obtained with a catalytic converter system.
Saab has not tested a thermal reactor/catalytic converter system (Ref. 2-32).
2.2.16.2.2 Problem Areas and Plans for Resolution
In addition to the general problem of catalyst durability discussed in Sec-
tion 2. 2. 16. 1. 2, Saab reports that catalyst attrition and loss of particulate
presents a serious problem associated with the base metal catalyst. Catalyst
poisoning with 4 ppm of phosphorous in the fuel was also experienced in
Test 12 on a car equipped with a Degussa catalyst.
2.2.16.2.3 Emissions
2.2. 16.2. 3. 1 Test Programs and Vehicle Description
A total of six tests have been reported by Saab on vehicles equipped with
its second-choice system. Of these, four (Tests 6, 7, 9, and 12) are or
have been run over the Saab MAR driving cycle, one (Test 8) is being con-
ducted over a "stop-and-go" driving cycle which consists of mixed city driving
with frequent cold starts, and one (Test 10) is being tested over the Saab
normal road driving cycle which is run 16 hours a day at an average speed of
44 mph and a maximum of 70 mph.
Test vehicles used for testing the Saab second-choice system include those
equipped with both 1. 85- and 2.0-liter engines, both automatic and manual
transmissions, and base metal, pellet-type catalysts from three different
manufacturers. Particular combinations employed are indicated together
with the emission results in Table 2-32.
2.2.16.2.3.2 Test Procedures
All test results were obtained in accordance with the 1975 CVS-CH test
procedure.
2.2.16.2.3.3 Emission Data
Low and high mileage emission results for the Saab second-choice system
tests are shown in Table 2-32.
2-111
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Table 2-32. Emission "Data--Saab Second-Choice System
Test No.
. 6
7
8
Car No.
301
301
314
Engine
Liters
1.85
'1.85
2.0
Fuel
System
EFI
EFI
Carb.
Catalyst Mfr
Kali-Chemie
Kali-Chemie
Monsanto
Mileage
0
3,410
4, 010
5,350
7,430
7,460
0
13
208
450
515
960
1,410
2, 170
2, 770
4, 310
5,930
7,360
0
60
110
160
Emissions, gm/mi
HC CO N°x
0.23 2.98 2.59
2.18 4.72 2.55
0.26 2.76 2.56
0.32 3.38 - 2.66
0.58 6.20 2.33
0.50 6.12 2.38
1.26 29.63 0.77
0.22 2.85 1.02
0.17 1.83 1.21
0.25 3.01 1.29
0.25 3.21 1.38
0.19 2.24 1.30
0. 20 1.90 - 0. 00
0.19 2.18 2.89
0.31 2.79 1.52
0.27 3.41 1.53
0.25 3.63 1.96
0.33 3.93 0.00
0.26 3.03 1.10
0.16 2.39 0.87
0.27 2.15 1.56
0.20 2.68 1.32
Remarks
MAR driving cycle
Test continuing
High CO unexplained; MAR cycle
NO unexplained
NOX unexplained; test terminated as
container cracked
With EGR; stop-and-go driving cycle
Test continuing
-------
Table 2-32. Emission Data--Saab Second-Choice System (Continued)
Test No.
9
10
12
Car No.
385
341
301
Engine
Liters
1.85
2.0
1.85
Fuel
System
EFI
EFI
EFI
Catalyst Mfr
Monsanto
Monsanto
Degussa
Mileage
0
43
185
195
208
592
764
2, 740
4, 210
6,380
8, 280
10,420
0
2, 170
2, 190
2, 300
0
20
615
630
1, 000
2,600
2,600
Emissions, gm/mi
HC CO N°x
0.07 0.34 1.52
0.10 0.75 1.10
0.18 0.93 1.54
0.22 1.75 1.99
0.21 1.57 2.14
0.24 1.18 2.07
0.22 1.44 2.37
0.22 1.33 2.54
0.23 1.18 2.59
0.19 1.40 2.10
0.29 1.34 2.14
0.50 2.97 2.87
0.31 1.61 1.75
1.09 8.89 1.31
0.61 4.16 1.58
0.79 6.81 1.49
0. 19 2. 11 1.66
0.21 0.95 1.75
0.37 5.44 2.01
0.32 5.81 1.81
0.16 6.22 2.00
0.74 15.66 2.52
1.64 30.72 3.09
Remarks
MAR driving cycle
Test continuing
Normal driving cycle
Test continuing
MAR driving cycle
Test terminated; catalyst poisoned
by 4ppm phosphorous
ts)
I
-------
2.2.16.2.3.4 Best Emission Results
The best low mileage emission levels reported by Saab for its second-
choice system without EGR were on Test 9 at zero miles. This vehicle was
h
equipped with a 1.85-liter engine, electronic fuel injection, secondary air
injection, and a Monsanto base metal catalyst. Emission levels achieved
were 0. 07 gm/mi HC, 0, 34 gm/mi CO, and 1. 52 gm/mi NO . "
5C
Only one vehicle has been tested using the Saab second-choice system with
EGR. This vehicle (Test 8) was equipped with a 2. 0-liter engine, a Zenith
carburetor, a Monsanto base metal catalyst, and metered EGR (rate not
specified). The best emission results achieved, at 60 miles, were 0. 16 gm/mi
HC, 2. 39 gm/mi CO, and 0. 87 gm/mi NO .
2.2.16.2.3.5 Test Data Variability
Test data variability is not discussed by Saab other than the general comment
reported in Section 2. 2. 16. 1. 3. 5.
2.2.16.2.4 Fuel Consumption and Performance Penalties
Fuel consumption penalties were not reported by Saab for its second-
choice system tests. Actual fuel consumptions ranged from 21 mi/gal on
Test 6 to 25 mi/gal on Test 9. Fuel consumption was not checked on Test 8
(the vehicle included EGR). Baseline fuel consumption was not reported.
A power loss of 5 percent was reported for all second-choice system tests
with the exception of Test 12; in this test a power loss of 3 percent was
reported.
Driveability was reported to have a rating of 5 (borderline) on the EGR-
equipped car used in Test 8, a rating of 6 on Tests 9 and 10, and a rating of
8 on Tests 6 and 7.'
2-114
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2.2.17 Toyo Kogyo
2. 2. 17. 1 First-Choice Systems
2.2. 17. 1. 1 Special Design Features
The system proposed by Toyo Kogyo for use on the rotary engine for model
year 1975 is currently planned to consist of a thermal reactor, improved
control of the secondary air injection system, and an improved induction
system. No EGR is. planned for use on the rotary engine for 1975. Toyo
Kogyo also indicates (Ref. 2-34) that a forced cooling system would be used
on the reactor for the rotary engine vehicle. This statement was not ampli-
fied further during the Toyo Kogyo testimony.
A first-choice system has not yet been selected by Toyo Kogyo for the
4-cylinder reciprocating piston engine. Development work is continuing on
three different systems for this engine. These include the thermal reactor
system, the HC/CO catalytic converter system, and a combination of the two.
No other details of these developmental systems were provided by Toyo Kogyo,
although it could be inferred from its testimony (Ref. 2-34) that EGR will
not be used on the 1975 model year reciprocating engine but rather is being
investigated on test bed engines for possible application to the 1976 model
year reciprocating engine emission control system.
2. 2. 17. 1. 2 Problem Areas and Plans for Resolution
The primary problem associated with the Toyo Kogyo rotary engine emission
control system is that the durability of the reactor has not yet been demon-
strated. Because of the increased reactivity required to meet the 1975
standards, the device is expected to operate at a core temperature approxi-
mately 130°F higher than the 1972 production model. The possible adverse
effects on underhood components of the vehicle caused by the increased tem-
perature are currently being investigated to determine whether it will be
necessary to make any modifications to the vehicle body structure or under-
hood components.
2-115
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With regard to the reciprocating engine systems, the major problem
encountered with the catalytic converter systems has been lack of adequate
durability. Details of the durability problem were not provided, nor were
the type or design of catalytic devices identified' Unsatisfactory results
were reported in efforts to devise a satisfactory catalyst overtemperature
protection system.
The thermal reactor device applied to the reciprocating engine has created
the usual problem of excessive heat in the engine compartment and, in addi-
tion, has created difficulties in compartment packaging. These problems
might require major modifications to the vehicle body structure and to the
layout of engine components.
2.2.17.1.3 Emissions
2. 2. 17. 1. 3. 1 Test Programs and Vehicle Description
The rotary engine test fleet consists of three 2750-lb vehicles equipped with
70-CID two-rotor rotary engines and manual transmission. Only low mileage
emission tests have been conducted. The reciprocating engine test vehicle
is equipped witha 110-CID engine. The test fleet consists of three vehicles
equipped with the thermal reactor system, two equipped with the catalytic con-
verter system, and three equipped with the thermal .reactor/catalytic con-
verter system. Emission tests of the reciprocating engine systems have also
been limited to low mileage.
Durability tests (50, 000 miles) are scheduled to start in May, 1972 and be
completed in September, 1972 for both the rotary and reciprocating engine
vehicles. The driving cycle to be followed was specified (Ref. 2-35) only as
"general durability testing of the vehicle-system combination on the road and
dynamometer to obtain the final design of the control system. "
2-116,
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2.2.17.1.3.2 Test Procedures
All emission test data reported by Toyo Kogyo were obtained in accordance
with the 1975-CVS-CH test procedure.
2.2. 17. 1.3. 3 Emission Data Summary
Emission levels achieved at low mileage on the rotary engine equipped with a
thermal reactor were 0. 17 gm/mi HC, 2. 2 gm/mi CO, and 0. 93 gm/mi NO .
These values represent the average of 18 tests obtained from three vehicles,
each of which had accumulated from 300 to 1000 miles. Individual test results
were not reported.
Low mileage emission results for the conventional engine with each of three
emission control systems are shown in Table 2-33. All results represent the
average emissions obtained from the indicated number of vehicles and indi-
vidual tests as reported by Toyo Kogyo. All tests were conducted on a 110-
CID engine. As was the case for the rotary engine vehicles, individual test
results were not reported.
2.2.17.1.3.4 Best Emission Results
Best overall emission results were achieved with the rotary engine as
reported above. For the reciprocating engine, the best results were achieved
with the thermal reactor-only system, which yielded average values of 0. 15
gm/mi HC, 2.6 gm/mi CO, and 2.3 gm/mi NO , as shown in Table 2-33.
X.
2.2.17.1.3.5 Test Data Variability
Test data variability was reported by Toyo Kogyo (Ref. 2-35) in terms of a
1 sigma standard deviation for each engine/emission control system. This
has been converted to the coefficient of variation, cr/x, %, for ease of com-
parison with data variability presented by other manufacturers, as shown in
the following table.
2-117
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Table 2-33. Toyo Kogyo Reciprocating
Engine Emission Results
Control System
Thermal Reactor
, (Type A)*
HC/CO Catalyst
(Type X)*
Thermal Reactor
(Type B)* plus
Catalyst (Type Y)'"
.
No. of Vehicles
Tested
2
2
3
Not otherwise identified
No. of Tests
Averaged
6
6
9
Emissions,
gm/mi, CVS-CH
HC CO N°x
0. 15 2.6 2.3
0.29 2.8 2.6
0.25 2.9 2.5
Mileage
When Tested
300 - 1100
400 - 500
500 - 600
v
oo
-------
Toyo Kogyo Test Data Variability
(Coefficient of Variation, cr/x)
Coefficient of
N t Variation, tr/x,%
Engine Control System Tests HC CO
Rotary Thermal Reactor 18 17.6 10.9
Recipr. Thermal Reactor 6 16.7 11.5
Recipr. Catalytic Converter 66 13.8 8.9
Recipr. Reactor plus Converter 12. 0 9. 7
2.2.17.1.4 Fuel Consumption and Performance Penalties
The fuel consumption penalty for the rotary engine was reported by Toyo
Kogyo to be 5 percent below the 1972 model year vehicle which is also
equipped with a thermal reactor. The reported 5 percent loss in fuel
economy is due to (unspecified) changes in the air/fuel ratio (Ref. 2-35).
Driveability of the 1975 rotary engine vehicle is rated by Toyo Kogyo as
"fair, " as is the 1972 model year vehicle.
The fuel consumption penalties are reported for the reciprocating engine
emission control system as 10 percent for the thermal reactor system and
5 percent for both the catalyst and reactor/catalyst systems when compared
to the 1972 model year production vehicle. Driveability is rated as "fair"
for all three emission control systems.
2.2. 17.2 Alternate Systems
No second-choice system is planned by Toyo Kogyo for use on the 1975 rotary
engine vehicle. At the present time, it plans to continue with the reactor
core fabricated from 20-percent chrome, 3-percent aluminum sheet metal
stock. They did indicate, however, that they might have to go to a reactor
core material with some nickel content if the results of the durability tests
so indicate.
2-119
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None of the previously described emission control systems being developed
by Toyo Kogyo has been designated as a second-choice system and will not
be reviewed in this section.
2. 2. 18 Toyota
2.2.18.1 First-Choice Systems
2.2.18.1.1 Special Design Features
The Toyota first-choice system, designated System 75rA, comprises an
oxidizing catalytic converter, air injection, EGR, and engine modifications
(Refs. 2-36, 2-37). The catalytic converter is a pelletized noble metal design
utilizing palladium as the catalyst agent (the source of the catalyst materials
was not specified; Toyota plans to develop and manufacture its own con-
tainer). The engine modifications include redesign of the induction system to
improve warm-up characteristics (low thermal inertia intake manifold),
carburetor improvements, and lean choke operation. Toyota also is investi-
gating a possible change in combustion chamber configuration to reduce HC
and NO emissions.
?c
Toyota states that the selection of System 75-A was based on the following
considerations:
a. The catalytic converter was essential to the goal of meeting
Federal emission standards for 1975.
b. EGR looked promising as a means of achieving the California
1974/75 NOX standards, and was in an advanced state of
development.
c. The engine modifications selected were based on improve-
ments under development and in use for a number of model
years.
The selection of palladium for the catalyst was a cost consideration
(palladium is one-third the price of platinum). The pelletized configuration
was selected in preference to a monolith structure partly because Toyota
believed the monolithic version tended to be poisoned by lead easier than the
larger volume pelletized design.
2-120
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2.2.18.1.2 Problem Areas and Plans for Resolution
In general, the performance and durability of the 75-A system are
unsatisfactory. Low mileage emission results meet the 1975 standards but
fail to meet Toyota's low mileage engineering goals. The possibility of
improving catalyst warm-up characteristics by mounting the converter closer
to the engine is under consideration; however, this poses a potential problem
of converter overheating.
With regard to other system problems, Toyota is still working to achieve
and maintain an optimum air/fuel ratio which would permit both the catalyst
and EGR system to operate at best efficiency.
Component problems in the Toyota system include catalyst durability, con-
verter case deformation and rupture, and carburetor icing and throttle valve
freezing in cold weather due to EGR (the Toyota system introduces recircu-
lated gas between the carburetor venturi and throttle valve). Although no
data were available to support this claim, Toyota feels that 0. 05 gm/gal lead
content gasoline will be unsatisfactory; some toxification of the catalyst is
suspected even with the 0. 02 gm/gal gasoline that currently is being used in
the test vehicles. High fuel consumption and degraded performance were
additional problems associated with the first-choice system.
With regard to the air/fuel problem, Toyota plans to make carburetor
improvements, including the addition of altitude compensating devices. It
also is considering the use of fuel injection.
With regard to catalyst system durability, Toyota is working on the develop-
ment of a stronger catalyst carrier and is studying new designs for the
structure and suspension of the case. Monolithic systems are also being
investigated.
2-121
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The EGR problems are being approached in several directions, including
coating the throttle shaft with a special protective material, controlling EGR
gas temperature, and terminating the recirculating flow at a minimum engine
temperature. -
2.2.18.1.3 Emissions
2.2.18.1.3.1 Test Programs and Vehicle Description
Toyota's testing of its complete emissions package is limited. Only one
vehicle durability run of the first-choice 75-A system has been made. One
more first-choice vehicle test was started recently. The test vehicle is
equipped with a 96. 9-CID, 4-cylinder engine and an automatic transmission.
The vehicle has an inertia wheel rating of 2500 Ib.
2.2.18.1.3.2 Test Procedures
Durability mileage accumulation was accomplished using the prescribed EPA
driving cycle and emission tests were conducted using the CVS method. It
was not specified that 1975-CVS-CH procedures were used. The test program
deviated from nonstandard practice in that maintenance was performed at
each4000-mile test interval (the maintenance was described as "engine adjust-
ments"; no further description was provided).
2.2.18.1.3.3 Emission Data Summary
Data from the single durability test of the first-choice system are shown in
Table 2-34. Toyota's low mileage emission goals of 0. 19, 1. 5, and 1. 9
gm/mi, respectively, for HC, CO, and NO are exceeded for the HC and CO
X.
pollutants at zero miles. Two entries are shown for each 4000-mile test
point. These are the emission results obtained before and after conducting
the maintenance mentioned above. At or near the 12, 000-mile point it was
observed that the converter case had broken and that the catalyst was
scattered. The test was then terminated.
2-122
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Table 2-34. Toyota First-Choice System Durability
Test Emission Results
Emission
Control
System
75-A
Mileage
0
4, 000
8, 000
12, 000
1975 CVS-CH Emissions, gm/mi
HC
0.21
0.39
0. 29*
0. 51
0. 27*
0.46
0.36*
CO
2.60
2.67
2. 13*
2.56
2. 82*
4.13
2. 55*
NO
X
1.16
1. 30
1.36*
1.47
1.29*
1.39
1.25*
^Engine adjusted.
Note: Catalytic converter damage found at 12, 000 mi.
-------
2.2.18.1.3.4 Best Emission Results
Best results are represented by the data shown at zero miles; that is,
0.21 gm/mi HC, 2.60 gm/mi CO and 1. 16 gm/mi NO .
3£
2.2.18.1.3.5 Test Data Variability
Toyota states that tests of its prototype 1975 emission package vehicles
showed variations in HC, CO, and NO emissions of 50, 30, and 30 percent,
X
respectively, about the mean values.
2.2. 18. 1.4 Fuel Consumption and Performance Penalties
When operated over the driving schedule of the 1975 Federal test procedure,
the 75-A system showed an increase in fuel consumption of 10 percent.
The following performance problems were observed in the driveability test
vehicles: power loss of 10-20 percent, torque loss at lower engine speeds of
20-50 percent, engine overheating, run-on, difficulty in hot restarting, tip-in,
rough idle, engine stalling, surging, hesitation, back-fire, poor acceleration
(especially with EGR operation), and vibration.
2.2.18.2 Alternate Systems
2.2.18.2.1 Special Design Features
Toyota does not have an alternate system for the 1975 model year. Two other
systems are currently under development. These systems, designated 76-A
and 76-B, appear to be targeted toward the 1976 model year application. The
76-A system incorporates engine modifications, EGR, an oxidizing catalyst,
and a reducing catalyst. The 76-B system contains the same components as
the 76-A and, in addition, incorporates a thermal reactor.
2-124
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Durability test results for these systems are limited; the data presented
show that neither system met the 1976 standards at zero miles. Both sys-
tems failed the 1975 CO standard at relatively low mileage: 76-A at or before
4000 miles and 76-B at or before 8000 miles. Additional information on these
systems may be found in Reference 2-37.
2.2.19 Volkswagen
2.2.19.1 First-Choice System
2.2.19.1.1 Special Design Features
Using the building-block approach, Volkswagen is developing its 1975 system
so as to permit the add-on of a reducing catalyst (or catalyst bed) for the 1976
model year vehicle (Refs. 2-38, 2-39, 2-40, 2-41). Two first-choice 1975 systems
are identified. Both use a thermal reactor, an HC/CO converter, and EGR.
One system employs carburetion, the other employs "conventional EFI
(Electronic Fuel Injection). "
The thermal reactor serves principally as a warm-up device for the catalytic
converter. The opposed-piston Volkswagen engine poses special problems in
this regard because two reactors are required in order to effect a close
engine mounting arrangement. The catalytic converter is a monolithic type
(the Johnson-Mathey AC-8 noble metal design is preferred). A ceramic
monolithic substrate manufactured by American Lava is used.
In addition to the above systems which are designed for the opposed-piston
air-cooled engines, Volkswagen delineated another first-choice system which
is designed for the water-cooled in-line engine used in the Audi vehicle. This
emission system basically comprises an HC/CO converter with EGR.
A component/feature description for each of the systems discussed above is
provided in Table 2-35.
2-125
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Table 2-35. Volkswagen First-Choice Systems Description
Air-Cooled Engine (VW)
Water-Cooled Engine (Audi)
Concept 1 (EFI)
Concept 2 (Carburetion)
Concept 4
EFI
EGRa
Air Injection0
Thermal Reactor
Catalytic Converter
(HC/CO)
Converter Overtemperature
Diverter System
Low Thermal Inertia
Exhaust Manifold
Modified Carburetor
EGRb
Air Injection0
Thermal Reactor
Catalytic Converter
(HC/CO)
Converter Overtemperature
Diverter System
Low Thermal Inertia
Exhaust Manifold
Modified Carburetor
EGRb
Air Injection
Extreme Spark Retard
during warm-up.
Catalytic Converter (HC/CO)
Converter Overtemperature
Diverter System
Low Thermal InertiaV
Exhaust Manifold
Upstream throttle entry, effective after warm-up
Upstream carburetor entry at low load, downstream at high load; effective after warm-up
Into exhaust ports and thermal reactor on warm-up; thereafter into thermal
reactor only
I
nto exhaust ports on warm-up; thereafter into HC/CO converter
-------
2.2.19.1.2 Problem Areas and Plans for Resolution
The problems discussed by Volkswagen include the following: (1) increased
fuel consumption, (2) decreased engine performance, (3) mechanical stabil-
ity of the catalyst support monolith, (4) potential of fire due to the high
temperature operation of the converter, and (5) maintaining emission con-
trol system adjustment. In addition to these problems, Volkswagen identi-
fies major design problems in the following areas: (1) sealing and lubricating
the exhaust by-pass valve; (2) EFI system performance; (3) carburetor air/
fuel balance; and (4) mechanical durability, reactivity loss, and start-off per-
formance deficiencies in the catalytic converter.
Volkswagen sees no possibility of improving the fuel consumption behavior of
the control system in the foreseeable future. Some improvement in drivea-
bility might be achieved by substituting "special reactor devices" (not further
identified) for the currently used lean choke operation. The performance loss
problem is stated to be intractable except by the device of increasing engine
displacement or mean effective cylinder pressure. Both of these solutions'
would require a major engine redesign.
2.2.19.1.3 Emissions
2.2.19.1.3.1 Test Programs and Vehicle Description
Volkswagen asserts that it has conducted 250 emission tests in the course
of developing and improving Volkswagen control systems. These tests were
performed exclusively on low mileage vehicles using air-cooled engines with
displacements of 1.6 and 1. 7 liters and water-cooled engines of 1.6 liter
displacement. While Volkswagen has operated durability test cars and has
accumulated 15,000 kilometers on at least one of its first choice systems,
this program is being conducted solely for the purpose of evaluating mechanical
durability and has not been interrupted to measure emissions.
2-127
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2.2.19.1.3.2 Test Procedures
Volkswagen (low mileage) emission results were obtained using 1975 test
procedures.
2.2.19.1.3.3 Emission Data Summary
Low mileage emission data for the Volkswagen first-choice emission systems
are shown in Table 2-36. The data represent mean values for several tests
of different vehicles having less than 600 miles accumulated. Included in the
emissions package reflected by the data is a NO reducing catalyst.
X
Volkswagen's basic plan is to delete the reducing catalyst for the 1975 system
if sufficient NO control can be achieved by other means.
5C
2.2.19.1.3.4 Best Emission Results
The best overall emission results for each of the Volkswagen first-choice
systems are included in Table 2-36. It may be seen that the air-cooled engine
does considerably better in CO control with the Volkswagen thermal reactor
included in the system. Concept 4 (water-cooled engine without thermal reac-
tor) appears to accomplish satisfactory CO control by the warm-up extreme-
spark-retard technique. The best data for both engine types are exemplified
by the following emission values for Concept 1: HC = 0.25, CO = 2. 2, and
NO = 0. 39 gm/mi.
X.
2.2.19.1.3.5 Test Data Variability
Data needed to evaluate variability were not provided.
2.2.19.1.4 Fuel Consumption and Performance Penalties
The emission control systems which Volkswagen has under development for
meeting 1975 standards increase fuel consumption by at least 20 percent over
1974 models, decrease engine performance by 10 to 25 percent, and adversely
affect driveability by causing hesitation during acceleration and cruise,
particularly if the engine is operated at lower than normal temperature. The
loss of performance is stated to be the direct consequence of modifying the
2-128
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Table 2-36. Low Mileage Emission Data Summary--Volkswagen
First-Choice Systems (with NO Converter)
Concept No.
and
(Engine )
1
(Air Cooled)
1
(Air Cooled)
2
(Air Cooled)
4
(Water
Cooled)
Emissions, gm/mi
(Mean)
HC CO N°x
0.38 2.2 0.64
0.46 5.54 0.5
0.49 4.9 0.46
0.82 4.04 0.57
No. of
Vehicles
3
3
1
4
No.
of
Tests
10
6
9
10
Emissions, gm/mi
(Overall Best Value)
HC CO N°x
0.25 2.2 0.39
0.49 4.78 0.42
0.39 2.8 0.46
0.62 3.35 0.29
Test
Procedure
1975-CVS-CH
1975-CVS-CH
1975-CVS-CH
1972-CVS-C
Remarks
With NO converter
X
With NOX converter,
without thermal
reactor
With NO converter
X
-------
combustion process to reduce emissions. Volkswagen provides little hope
for overcoming these difficulties without a major redesign of the engine.
2.2. 19.2 Alternate Systems
2.2. 19.2. 1 Special Design Features
The Volkswagen alternate 1975 system comprises an advanced EFI (Electronic
Fuel Injection) device, EGR, a low thermal inertia exhaust manifold, an
HC/CO oxidation catalyst, and a catalyst overtemperature protection system.
Few details concerning this alternate system were provided in the Volkswagen
submittal or testimony transcript. Ten tests (1975 CVS-CH) of a single (air-
cooled engine) vehicle equipped with this system, including the NO catalyst
bed, yielded the following results:
Emissions, gm/mi
Values HC CO NO
x
Mean Value 0.35 1.36 0.31
Best Overall Value 0.20 2.01 0.11
2.2.20 Volvo
2.2.20.1 First-Choice Features
2.2.20.1.1 Special Design Features
The Volvo first, choice system comprises the following subsystems
(Refs. 2-42, -43, -44, -45):
Catalytic converter (platinum/monolithic)
Secondary air supply
Catalyst protection warning system
Exhaust gas recirculation
Engine modifications
Fuel injection system
Modified intake system
2-130
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Both Engelhard and Johnson-Mathey platinum catalytic converter designs
are being evaluated for use in this system. The fuel injection system is being
developed by Bosch, Germany, and features a feedback device which senses
the quantity of exhaust gas recirculated to the engine intake.
Volvo has worked with thermal reactors and catalytic converters since early
1970. Its selection of a monolithic, noble metal catalytic converter for the
first-choice system is stated to be based on a number of considerations includ-
ing the following: (1) emission results (low mileage) met engineering
standards, (2) fuel economy and driveability were favorable compared to
other systems, (3) installation and attrition problems were minimized,
(4) mechanical failures were reduced, and (5) the device offered the best
possibility for incorporation into a complete emissions package which could
meet the 1975 standards.
2.2.20.1.2 Problem Areas and Plans for Resolution
Like other automobile manufacturers experimenting with catalyst systems,
Volvo has been unable to demonstrate satisfactory durability of the catalytic
converter and has experienced problems in catalyst attrition, mechanical
failure overheating, noise, and rapid deterioration in conversion efficiency.
According to Volvo, the last problem is due in part to the use of 0. 05 gm/gal
lead content fuel. More recent testing has been accomplished with 0. 015
gm/gal fuel which appears to provide better performance with mileage
accumulation.
Maximum mileage achieved with the Volvo first-choice system was
accomplished with an Engelhard PTX 416 converter which, .according to
testimony presented at the Volvo recall hearing on April 24, 1972, failed
at 29, 000 miles (see Table 2-37). By way of attacking the durability problem,
Volvo has ordered and intends to test other Engelhard PTX converter designs.
One type has a layered, as opposed to a rolled, substrate structure. Another
2-131
-------
Table 2-37. Volvo First-Choice System High Mileage Emissions
Test
No.
601
641
679
715
756
766
851
941
1020
1073
1080
1086
1091
Car Reg. No.
OB 46234
(Volvo 144,
engine B20F,
automatic
transmission)
OB 44085
(Volvo 144
engine B20F)
x f-i a
Mileage
at test
0
1, 600
3,864
5,815
8, 138
9,370
9,415
14, 283
18, 221
22,875
22,900
22,950
25,344
29,900
% Excess
Fuelb
C
.
£
Emissions, gm/mi
~~ TT~ NO
CO HC -x
2.17 0.21 1.31
1.33 0.28 1.60
0.94 0.27 2.35
0.91 0.31 1.79
6.14 0.48 1.76
9.55 0.45 1.59
2.08 0.18 1.82
0.88 0.18 2.07
1.34 0.46 1.78
2.67 0.51 2.18
4.33 0.35 2.05
3.70 0.20 1.76
2.45 0.24 1.82
Catalytic
Converter
Engelhard
PTX-416
(Spiral
Wound )
Converter
from car
OB 46234
Remarks
With EGR
Engine
problems
With EGR
EGR valve
changed.
d
-
Failure
aTotal mileage accumulated on catalytic converter
Referenced to an unspecified nominal setting
CA11 tests use 1975 CVS-CH procedure
Fuel injection nozzle changed (poor driveability)
-------
type with the layered structure uses a new improved catalyst coating. Ten
of these new designs will be installed in durability test cars; others will be
used in low mileage cars for testing different aspects of the first-choice
emission system operation.
2.2.20.1.3 Emissions
2.2.20.1.3.1 Test Programs and Vehicle Description
Durability testing of the Volvo system has been conducted primarily on a
subsystem basis; complete system vehicle testing had just been started as
of the date of the Suspension Request Hearing.
The vehicle test program to date has been performed with Volvo vehicle
models 142 and 144 fitted with engine-type B20F (4-cylinder engine with
electronically controlled fuel injection).
The test fleet consists of about 15 cars fitted with emission control systems
in various development and engineering phases. Both Engelhard and Johnson-
Mathey noble metal monolithic catalytic converter systems are being tested
for the first-choice system; other catalysts (including AC-Delco, UOP, and
Grace base metal types) are being tested on a second-choice basis.
Wherever low mileage results are promising, the Volvo testing procedure
is to continue to accumulate mileage on those vehicles and systems that dis-
play good performance. The high mileage test fleet, therefore, comprises
those vehicles that have demonstrated good, low mileage test performance.
2.2.20.1.3.2 Test Procedures
The 1975 Federal test procedure (three-bag cold/hot start technique) is being
used in the test program. The driving cycle for mileage accumulation was
not specified.
2-133
-------
2. 2. 20. 1. 3. 3 Emission Data Summary
Low mileage emission results for Volvo's first-choice systems incorporating
EGR were not provided in the submission data or the hearing testimony
available at this writing. Low mileage results without EGR and for different
catalytic converter devices are shown in Table 2-38.
High mileage emission results for car OB 46234 are shown in Table 2-37.
It is noted that the vehicle is equipped with EGR. The jump in CO emission
level for Tests 756 and 766 was stated by Volvo to be due to a faulty thermostat
which caused excessive choking. The catalytic converter used was installed
in another vehicle (see Table 2-37) and accumulated 25, 344 miles with
emission levels of 0.24, 2.45, and 1.82 gm/mi ,for HC, CO, and NO ,
3C
respectively. The Volvo recall testimony of April 24 reports that this catalyst
failed mechanically at 29,900 miles.
2.2.20.1.3.4 Best Emission Results
The maximum low mileage achievement shown in the Table.2-38 data is for
Vehicle OB 46232 which accumulated 2030 miles with emission levels of 0. 28,
1.59, and 2. 9 gm/mi for HC, CO, and NO , respectively, using the Engelhard
.X
PTX 416 converter.
According to Table 2-37, the maximum high mileage achieved within standards
was accomplished with Vehicle OB 44085 using an Engelhard converter trans-
ferred from another vehicle. Emission levels at a total (converter ) accumu-
lated mileage of 25, 344 miles were 0. 24, 2. 45, and 1. 82 gm/mi for HC, CO,
and NO , respectively.
3c
2.2.20.1.3.5 Test Data Variability
The variability of the test data at low mileage is best expressed in terms of
the range in the emission results at test mileages under 600 miles as follows.
The fuel setting in these tests was varied between 0 and -6 percent.
2-134
-------
Table 2-38. Volvo First-Choice Emission System--Low Mileage Emissions
CO
(Jl
Test
No.
433
508
542
445
468
499
520
550
524
549
628
680
711
757
776
467
475
Car Reg. No<
OB 46234
(Volvo 144
engine B20F
automatic
transmission)
OB 46232
(Volvo 144
engine B20F
manual
transmission)
OB 44448
Mileage
at test
0
205
600
25
160
185
0
155
12
146
855
1,410
1,790
2, 030
2,610
100
200
1300
% Excess
Fuela
0
0
0
-4
-4
-4
0
0
-4
-4
-4
-4
-4
-0
-4
-4.5
-6
' -6
Emissions, gm/mi
CO HC N0x
2.18 0.12 2.12
1.04 0.15 3.23
1.33 0.29 3.82
1.60 0.03 2.64
0.66 0.10 2.82
0.61 0.19 3.44
1.92 0.43 2.60
1.59 0.15 3.07
1.12 0.26 2.81
1.49 0.26 3.24
0.89 0.22 3.24
0.60 0.27 2.22
0.85 0.32 2.20
1.59 0.28 2.90
1.54 0.58 2.23
1.56 0.19 3.32
1.16 0.14 2.87
4.28 0.72 3.65
Catalytic
Converters
Engelhard
PTX-416
(Spiral
Substrate)
Engelhard
PTX-416
(spiral
Substrate)
Johnson-
Matthey
AEC 3
Remarks
Without EGR
Automatic transmission
Same reactor unit
Without EGR
Manual transmission
Same reactor unit
Without EGR
Automatic transmission
With reference to an unspecified nominal setting
All tests with 1975 CVS-CH test procedure
C100% catalyst attrition at next test.
-------
Range of Emission Results, gm/mi
HC CO NO
x
0.03-0.43 0.60-2.18' 2.12-3.82
The high mileage data on the first-choice system does not permit a statement
concerning variability to be made.
Tests carried out on the same car and with the same test equipment are
reported by Volvo to produce results which vary up to about 50 percent above
and below the mean value.
2. 2. 20. 1.4 Fuel Consumption and Performance Penalties
Volvo states that the increased backpressure created by the catalytic reactor,
along with the power loss due to the air pump, reduces engine performance.
The sum of these losses is stated to be about 10 percent for the Engelhard
converter on engine type B20E and accounts for a fuel consumption increase
of about 20 percent.
2.2.20.2 Alternate Systems
2. 2. 20. 2. 1 Special Design Features
The Volvo second- and third-choice systems differ from the first-choice
system only in the design of the catalytic converter. Instead of the noble
metal monolithic device used in the first-choice system, the second- and
third-choice systems utilize base metal pelletized converters. The second-
choice system employs a UOP "mini" reactor which mounts directly to the
engine exhaust manifold. The third-choice system employs floor-mounted
base metal catalysts of UOP and AC-Delco design.
The Volvo fourth-choice system comprises a thermal reactor, EGR, and a
rapid warm-up device. This system is described in further detail in Sec-
tion 6, Thermal Reactors. The discussion that follows addresses the Volvo
second- and third-choice catalytic converter systems.
2-136
-------
2. 2. 20. 2. 2 Problem Areas and Plans for Resolution
The general problem of attrition, performance deterioration, converter over-
heating, noise, and heat emission to the local environment as discussed in
connection with the first-choice monolithic system appear also to apply to
Volvo's base metal catalyst systems. Vibrations from pulsations in the
exhaust and from second-order inertia forces in the 4-cylinder engine have
resulted in severe attrition and breakdown of the UOP mini systems. Three
of these converter units are reported to have failed.
Presumably, additional testing of the base metal catalytic converter systems
will be conducted. Specific solutions applicable to second- and third-choice
system problems are not discussed in the Volvo submittal.
2.2.20.2.3 Emissions
2. 2. 20. 2. 3. 1 Test Programs and Vehicle Description
As described in the discussion of Volvo's first-choice system, the vehicle
test program to date has been performed with Volvo vehicle models 142 and
144 fitted with engine type B20F (4-cylinder engine with electronically con-
trolled fuel injection). The total test fleet consists of about 15 cars fitted
with emission control devices in various stages of development.
2.2.20.2.3.2 Test Procedure
The 1975 CVS-CH Federal test procedure is used. The duty cycle for mileage
accumulation was not specified.
2. 2. 20. 2. 3. 3 Emission Data Summary
Emission results achieved on low mileage cars for the second-choice close-
coupled UOP "mini" converter, along with low mileage results for the
third-choice, floor-mounted AC-Delco system, are shown in Table 2-39. One
high mileage test has been performed with the second-choice UOP system.
The results from this test are shown in Table 2-40.
2-137
-------
Table 2-39. Volvo Alternate Systems--Low Mileage'Emissions
Test
No.
200
215
247
269
273
479
489
498
516
525
528
732
Car Reg.
OA 34293
OA 34293
OB. 44448
OB 50430
Mileage
at test
125
210
275
350
375
1, 630
1, 650
1, 690
1, 720
1, 760
1, 800
130
120
% Excess
Fuela
0
0
0
0
0
-9.5
-2.5
-8
-7
-7
-9.5
0
0
Emissions, gm/mi
CO HC NOX
1.23 0.11 2.20
1.10 0.14 2.39
2.10 0.25 2.29
1.19 0.13 2.29
1.62 0.12 2.15
1.24 0.23 1.16
2.72 0.28 1.64
2.64 0.40 1.73
2.49 0.30 1.60
2.60 0.36 1.72
1.16 0.21 1.68
2.74 0.36 3.70
2.43 0.24 3.14
Catalytic
Converter
UOP '
UOP
UOP
UOP
UOP
UOP
UOP
UOP
UOP
UOP
UOP
AC-Delco
AC-Delco
(new pellet
type)
Remarks
Without EGR
With EGR
(second-
choice
system)
Without EGR
3. '
Referenced to an unspecified nominal setting
b!975 CVS-CH test procedure
00
00
-------
Table 2-40. Volvo Alternate Systems--High Mileage Emissions
Test
No.
602
647
692
733
Car Reg.
OB 44085
Automatic
transmission
Mileage
at test
0
1, 600
4, 093
5, 852
7, 000
% Excess
Fuela
-8
-8
-5
-5
Emissions, gm/mi"
CO HC N0x
1.69 0.12 1.24
0.66 0.24 1.58
0.56 0.47 1.76
6.24 0.18 1.26
Catalytic
Converter
UC
'
>P
Remarks
With EGR
(second-choice
system)
Reactor
breakdown
Referenced to an unspecified nominal setting
b!975 CVS-CH test procedure
to
-------
2. 2. 20. 2. 3. 4 Best Emission Results
The Table 2-39 data show that the second-choice (UOP) system was well
within the limits of the 1975 standards at 1800-miles, with emission levels of
0.21, 1.16, and 1. 68 gm/mi for HC, CO, and NO , respectively. The
Ji
maximum mileage accumulated on this system was 7000 miles, at which
point reactor breakdown occurred (see Table 2-40). The CO standard was
exceeded at a mileage between about 4000 and 5800 miles.
2. 2. 20. 2. 3. 5 Test Data Variability
The variability of the data is typified by the Table 2-39 results for the
second-choice system (with EGR). In the mileage range shown, that is,
from 1630 to 1800 miles, the data vary about the mean by 42 percent for HC
and 85 percent for CO.
2.2. 20. 2. 4 Fuel Consumption and Performance Penalties
These performance parameters are not discussed for the second- and third-
choice Volvo systems.
2-140?
-------
REFERENCES
2-1 American Motors Corporation, Technical Data Submittal provided by
AMC at the request of the EPA Suspension Request Hearing Panel,
20 April 1972.
2-2 American Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, B.C., 11 April 1972.
2-3 American Motors Corporation, Technical Data Submittalprovided by
AMC at the request of the EPA Suspension Request Hearing Panel,
25 April 1972.
2-4 American Motors Corporation, Letter to Mr. William D. Ruckelshaus,
Administrator, Environmental Protection Agency, 4 April 1972.
2-5 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the Clean
Air Act," March 1972.
2-6 Chrysler Corporation, Technical Data Submittal provided by Chrysler
at the request of the EPA Suspension Request Hearing Panel,
25 April 1972.
2-7 Chrysler Corp'oration, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C. ,
20 April 1972.
2-8 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards," Volumes I and II, 5 April 1972.
2-9 Ford Motor Company, Technical Data Submittal provided by Ford at
the request of the EPA Suspension Request Hearing Panel, 26 April
1972.
2-10 Ford Motor Company, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C. ,
19 April 1972.
2-11 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
2-12 General Motors Corporation, Technical Data Submittal provided by
GM at the request of the EPA Suspension Request Hearing Panel,
21 April 1972.
2-141
-------
REFERENCES (continued)
2-13 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, "Technical Appendix to Summary Statement of Engelhard,
Addendum II," 24 April 1972.
2-14 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 17 April 1972.
2-15 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, B.C., 26 April 1972 (recall).
2-16 International Harvester, "Request for One-Year Suspension of 1975
HC and CO Light-duty Emission Standards Submitted to EPA,
Washington, D. C. , " 29 March 1972.
2-17 International Harvester Company, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, B.C., 14 April 1972.
2-18 Automobile Emissions Control - A Technology Assessment as of
December 1971, Mobile Source Pollution Control Program, Office
of Air Programs, Environmental Protection Agency, 1 January 19V2.
2-19 Universal Oil Products, Technical Data Submittal provided by UOP
at the request of the EPA Suspension Request Hearing Panel,
21 April 1972.
2-20 British Leyland Motors, Inc. , "EPA Hearing of Volvo Application
for Deferment of Emission Legislation Applicable to 1975 Model
Year Vehicles," March 1972.
2-21 British Leyland Motors, Inc., Technical Data Submittal provided by
British Leyland at the request of the EPA Suspension Request Hearing
Panel, 14 April 1972.
2-22 British Leyland Motors, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D.C. ,
11 April 1972.
2-23 Daimler-Benz, "Statement of Daimler-Benz AG before the Environ-
mental Protection Agency, Washington, D. C. , " April 1972.
2-142
-------
REFERENCES (continued)
2-24 Daimler-Benz AG, Technical Data Submittal provided by Daimler-Benz
at the request of the EPA Suspension Request Hearing Panel,
19 April 1972.
2-25 Mercedes-Benz Company (Daimler-Benz AG), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental
Protection Agency, Washington, D. C. , 19 April 1972.
2-26 Mitsubishi Motors Corporation, "A Status Report of Emission Control
for 1975 and 1976 Light-Duty Vehicles, " October 1971.
2-27 Nissan Motor Corporation in U.S.A. (Datsun), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental Protection
Agency, Washington, D. C. , 11 April 1972.
2-28 Nissan Motor Company, Ltd. , (Datsun), Technical Data Submittal
provided by the Nissan Motor Company at the request of the EPA
Suspension Request Hearing Panel, 24 April 1972.
2-29 Nissan Motor Company, Ltd. , (Datsun), "Summary Statement of
Information," 5 April 1972.
2-30 Nissan Motor Company, Ltd. , (Datsun), Technical Data Submittal
provided by the Nissan Motor Company at the request of the EPA
Suspension Request Hearing Panel, 27 April 1972.
2-31 Rolls-Royce Motors Limited, "Emission Control for 1975 and 1976
Light-Duty Motor Vehicles -- Status Report, " 4 November 1971.
2-32 Saab-Scania, Inc., Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C. ,
12 April 1972.
2-33 Saab-Scania of America, Inc. and Saab-Scania AB, "Information
Submitted in Response to Subpoena dated March 17, 1972 of
Environmental Protection Agency, Washington, D. C. "
2-34 Toyo Kogyo Company, Ltd. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, B.C., 21 April 1972.
2-35 Toyo Kogyo Company, Ltd. , "Statement of Toyo Kogyo Company, Ltd. , "
April 1972.
2-143
-------
REFERENCES (continued)
2-36 Toyota Motor Company, Ltd., "A Summary of Toyota's Technology
and Processes for Meeting the 1975 Federal Emission Standards, "
5 April 1972.
2-37 Toyota Motor Company, Ltd. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
.B.C., 13 April 1972.
2-38 Volkswagen of America, Inc. , "Information and Documentary Materials
Relating to Volkswagen's Emission Research and Design Effort to
Meet 1975 Federal Emission Goals, " 10 April 1972.
2-39 Volkswagen of America, Inc. , Technical Data Submittal provided by
VW at the request of the EPA Suspension Request Hearing Panel,
28 April 1972.
2-40 Volkswagen of America, Inc. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 10 April 1972.
2-41 Volkswagen of America, Inc. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 11 April 1972.
2-42 AB Volvo, "Request for Suspension of the 1975 Emission Standards, "
9 March 1972.
2-43 AB Volvo, "Supplement to Request for Suspension of the 1975
Emissions Standards, " 15 April 1972.
2-44 Volvo, Inc., Transcript of Proceedings -- Auto Emissions Extension --
Environmental Protection Agency, Washington, D. C. , 10 April 1972.
2-45 Volvo, Inc., Transcript of Proceedings -- Auto Emissions Extension --
Environmental Protection Agency, Washington, D. C., 24 April 1972
(recall).
2-144
-------
3. ENGINE MODIFICATIONS
3. 1 BACKGROUND
With the establishment of the California automobile emission regulations in
1966, and the recognition that more stringent standards would probably evolve,
the automobile manufacturers initiated major development efforts directed
toward significantly reducing engine exhaust emission levels. These efforts
are typified by such programs as the Improved Combustion System (IMCO)
by Ford, the Controlled Combustion System (CCS) by General Motors, the
Cleaner Air System (CAS) by Chrysler, and by other supporting activities
such as the Inter Industry Emission Control (IIEC) program involving six
major petroleum manufacturers and five automobile manufacturers.
The above efforts, in conjunction with other research projects, have addressed
the more than 100 vehicle characteristics or components that affect exhaust
emission levels and have resulted in a large number of modifications to the
basic engine and its components. These include major refinements in the
ignition and carburetion systems, changes in the combustion chamber design,
changes in the compression ratio and valve timing, and changes in the exhaust
manifold including the addition of air injection.
As a result of all the modifications that have been applied to the 1972 auto-
mobiles, or those scheduled for inclusion in the 1973 models, exhaust emis-
sion levels have been substantially improved. HC and CO emissions have
been reduced by approximately 80 percent and NO emissions by approximately
Ji
40 percent compared to those from uncontrolled automobiles prior to 1966.
(Although the potential is available for making improvements in NO emissions
.X
that are similar, but smaller, to those for HC/CO, the performance penalty
that would be incurred in meeting even lower standards has prevented this
potential from being realized.)
3-1
-------
Presented in Table 3-1 are the average emission levels obtained from
American Motors (Ref. 3-1) certification tests and Ford (Ref. 3-2) develop-
ment fleet tests. Included for comparison are the typical emissions from
pre-1966 automobiles.
Table 3-1. American Motors Certification Data
and Ford Development Fleet Data
Emission
HC
CO
NO
X
Pre-1966
*i*
Uncontrolled
17
125
5
Ford
1972* 1973*"
2.37 2.09
24.2 17.15
2.22 2.42
Amer. Motors
1972** 1973
2.45 1.51
22.4 14.9
2.83 2.78
Reduction
Average, %
87
84
48
*1972 CVS-C Procedure
"1975 CVS-CH Procedure
While still further improvement in emission levels might be achieved by
additional modifications to the basic engine it is not reasonable to expect that
these gains would be very significant.
3.2 MODIFICATION REQUIREMENTS FOR 1975
In the past, emission improvements by basic engine modifications have kept
pace with the evolution of new and more severe standards, but the situation
for 1975 is significantly different. Emission level standards can no longer
be satisfied by improving the basic engine; compliance requires the addition
of aftertreatment devices. Further, the engine and any engine modifications
3-2
-------
required for compatibility with the 1975 system must also be compatible with
the components of a system which is capable of meeting the 1976 standards.
The oxidation catalyst, generally accepted as necessary to meet the 1975 HC
and CO standards, imposes new requirements on basic engine emissions as
well as engine performance in order to ensure satisfactory system emission
levels and, at the same time, provide acceptable driveability, economy,
durability, and safety. These new requirements result from limitations in
the catalyst warm-up time period, the conversion capability, and the temp-
erature tolerances of the catalyst. The EGR system, although previously
incorporated to meet 1973-74 NO standards, imposes additional new require-
ments which also relate to the basic engine emissions and performance.
These new EGR requirements result both from 1975 system interactions and
the projection of increased EGR flow rates and/or inclusion of a reducing
catalyst to meet the 1976 standards.
The EGR system and the oxidation catalyst primarily impact the carburetion
and ignition systems and impose demanding requirements with respect to their
response, precision, flexibility and control. Since the existing carburetion
and ignition systems have already been refined to their practical limits, it is
obvious that new types of these systems, with their associated sensors and
controls, are needed for any advanced emission control system. All of the
major automobile manufacturers are actively pursuing such new systems.
Undoubtedly, the new designs also will improve the basic engine exhaust
emissions: however, these designs have not been finalized and, therefore,
it is not possible to predict the level of improvement that might be achieved.
Other engine modifications may be required on the 1975 emission control
systems . but no automobile manufacturers have identified any which might
significantly influence emissions or performance of the basic engine.
3-3
-------
3.3 CARBURETION SYSTEM MODIFICATIONS
3.3.1 General
Carburetion systems of the conventional type in current production are, for
the most part, incompatible with the emission control systems proposed for
meeting the 1975 standards for the following major reasons:
a. To satisfy the condition for satisfactory emission control and
acceptable vehicle performance requires a significant improve-
ment in the preparation and distribution of the air/fuel
mixture.
b. To minimize emissions during the cold start period, before
the catalyst is sufficiently active, improvements are required
in the predictability and response of the choke system. In
addition, induction system improvements are required to
promote early fuel evaporation in order to reduce the period
of choke operation consistent with acceptable driveability.
c. To protect the durability of the catalytic converter and to
maximize its conversion efficiency, improvements are
required in the precision and response of the fuel metering
system to optimize the air/fuel mixture for the complete
range of operating modes and ambient conditions.
d. To provide the best balance between fuel economy, drive-
ability and power, improvements are required in the flexibility
of the fuel metering system. In addition, improvements are
required to provide for controllability to optimize the integra-
tion of variable ignition timing and EGR flow rates.
Achieving such a combination of all required improvements by modifying
existing designs is recognized to be impractical. Although a new type of
carburetion system is a major change requiring extensive development, it is
apparent that most of the automobile manufacturers are actively pursuing this
approach. Their motivation is primarily to obtain a competitive advantage,
for it is in this area that the technology is indeed well understood. This
technology can be exploited to offset the degradation in driveability,
.performance, and economy that would otherwise occur in 1975 vehicles.
3-4
-------
Because of the competitive advantage aspect, detailed progress in the
development of new carburetion systems is most likely regarded as classi-
fied information: therefore, progress reported by the automobile manufacturers
is probably general by intent and should be viewed accordingly.
3.3.2 Industry Status
All of the automobile manufacturers are actively engaged in some type of
development program to achieve a carburetion system that will provide
satisfactory performance and compatibility with their 1975 emission control
systems. These programs range from the improvement of the quality control
of existing carburetors to the development of completely new carburetion
systems of the conventional fuel metering (venturi) or timed fuel injection
types. Since these involve concurrent development of alternate systems,
most of the automobile manufacturers have not committed a particular design
for inclusion in their 1975 systems. This is particularity true for the foreign
automobile manufacturers. As a result, the industry status in this area is
presented only for the American automobile manufacturers and is based on
the material provided in References 3-3 through 3-7.
3.3.2.1 American Motors
To improve carburetor performance for its 1975 emission control system,
American Motors has applied refinements to the conventional carburetor
including altitude compensation, ambient temperature compensation, staged
power enrichment, an improved accelerator pump, and a modulated exhaust
gas recirculation system. In addition, the control of carburetor fuel flow
characteristics has been improved and the allowable fuel flow band tolerance
has been reduced.
The requirement for improved choke performance is recognized by American
Motors and a number of choke features are being investigated. These include
a staged choke pull down, choke plate offset, electrically heated chokes with
ambient temperature compensation, and a thermostatically controlled choke
heat by-pass system. Although the exact choke requirements have not been
3-5
-------
defined, American Motors states that new choke designs, unknown at this
time, will be required for their 1975-76 emission control system.
Currently, no in-house development programs for fuel injection systems are
underway at American Motors; however, the Bendix fuel injection system
developments are being monitored.
3.3.2.2 Chrysler
To provide better fuel metering, Chrysler is developing a number of carbure-
tor modifications, including modulated power valves, altitude compensation,
and improved lean mixture preparation.
An electrically assisted choke is a part of the Chrysler 1975 emission control
system. This type of choke -was developed and has been released for incor-
poration in 1973 models and is currently being improved for application in
1975 vehicles.
An electronic fuel metering system is under development at Chrysler. The
fuel injected is controlled by direct measurement of the air and fuel flows by
use of pulse-generating flow meters. Effects of intake air temperature and
barometric pressure are compensated for by electronic circuits. The fuel
flow control unit is operated by the metering electronics to provide pro-
grammed air/fuel ratios. This system would be compatible with the Chrysler
electronic engine control, which would then combine the ignition timing and
fuel metering functions. Development of this system has not progressed to a
point where it can be programmed for any specific Chrysler model year
vehicles.
3.3.2.3 Ford
A new concept carburetor system has been designed and development has
progressed to the production engineering phase. This new system, which
employes a variable venturi concept, is planned for limited application in
3-6
-------
some 1974 models and is targeted for inclusion in all 1975 emission control
systems. The salient features of this new design include the following:
a. Reduced metering system complexity and reduced number
of manufacturing variables that affect the carburetor-to-
carburetor statistical variation.
b. Improved hot fuel handling capabilities.
c. Elimination of the "off-idle to main system" transfer problem.
d. Improved metering stability and air/fuel mixture preparation.
e. Effective altitude compensation and cold enrichment.
Development of a predictable choke system is continuing at Ford. The current
"best system" features an electrically heated bimetal control which has the
potential to eliminate the dependence of the current choke system on manifold
vacuum for rapid release. In addition, a totally electronically programmable
choke system which uses a thermister sensor and servometer activators for
increased precision is also being investigated. These devices are currently
being screened prior to incorporation into Ford's new carburetor system.
Ford is also pursuing the development of an electronic fuel injection system.
A number of major problems have been uncovered during the development
program which require resolution before this type of system can be committed
to production.
3.3.2.4 General Motors
Three types of major conventional carburetors are planned as a part of the
General Motors basic 1975 emission control systems. These carburetors
include a modified one-barrel, a new plain tube two-stage progressive two-
barrel, and a modified four-barrel. A new type of air valve carburetor, in
place of the new but conventional two-barrel carburetor, is also being con-
sidered. Current plans are to continue with the present four-barrel carbure-
tor and improve it to achieve optimum overall emission control system per-
formance. These modifications include altitude compensation, improved
choke operation, improved metering accuracy, and revised evaporation
control provisions.
3-7
-------
General Motors considers that its present choke system is marginal and does
not have the potential for the improvement required to satisfy the 1975 emis-
sion control system requirements. A new system is being developed and
durability testing is in progress. An electronic fuel injection system is also
under development. To date, the performance of this system is not signi-
ficantly better than that of the General Motors conventional carburetor systems
and a number of areas require resolution before it could seriously be considered
for production.
3.3.2.5 International Harvester
International Harvester, in conjunction with its supplier, is planning to make
improvements in the carburetion system to be included in its 1975-76 emis-
sion control system. The progress of International Harvester's development
program, however, has been compromised by the unavailability of test-
specimens of advanced carburetor designs from its suppliers.
3.4 IGNITION SYSTEM MODIFICATIONS
3.4.1 General
The emission control systems proposed for 1975 require a high degree of
precision, reliability and flexibility of the ignition system to ensure satis-
factory emission levels and acceptable vehicle performance and driveability.
To promote early catalyst warm-up during a cold start and to optimize drive -
ability, performance, and economy within the constraints of NO control by
EGR requires modifications to the existing ignition systems to provide a
flexible and programmable spark timing control. In addition, the durability
of the catalyst requires high ignition reliability since it is intolerant to the -
high temperatures resulting from plug misfire or incomplete ignition.
/
The breaker point type of ignition systems in current production have inherent
limitations which preclude complete satisfaction of the requirements for the
1975 emission systems. Further, these systems are not compatible with
projected requirements for the sensing and control of the engine variables.
3-8
-------
Consequently, most of the automobile manufacturers are actively pursuing
the development of electronic ignition systems. This type of system not only
has the potential for the required precision reliability and control flexibility
but also provides a higher and more constant voltage output which would mini-
mize misfiring under certain engine operating conditions. In addition, it
eliminates the maintenance requirements associated with breaker point systems.
3.4.2 Industry Status
All of the American automobile manufacturers are considering the use of
electronic ignition systems of the breakerless type as a part of their 1975-76
emission control systems. While some of the foreign automobile manufac-
turers are also considering a change to electronic ignition systems, others
are not convinced of its necessity or benefits. Since the information available
from the foreign manufacturers on their ignition system development programs
or plans is very meager and inconclusive, the industry status is presented
for the American manufacturers only, and is based on the material provided
in References 3-1 through 3-5.
3.4.2.1 American Motors
Ignition systems of the breakerless inductor type and unitized designs are
being investigated by American Motors to obtain improved ignition reliability,
reduced maintenance, and extended useful life. To date, each of two systems
has been operated over 5, 000 vehicle miles and several additional installations
in vehicles are planned. Incorporation of this type of system is targeted for
1975-76 vehicles.
3.4.2.2 Chrysler
Chrysler Corporation has developed an electronic ignition system which is now
available on most 1972 vehicle/engine combinations. This is a breakerless
inductive system in which ignition coil current is switched by an electronic
control unit in response to timing signals produced by a distributor magnetic
pickup. To achieve more accurate and flexible control of spark timing at all
3-9
-------
engine operating conditions an improved version of this system is being
developed and is planned as a part of Chrysler's 1975 emission control system.
In conjunction with the above type of ignition system, Chrysler also proposes
an electronic engine control system for its 1975 vehicles. This control
system combines the operating logic of several systems into one control unit.
Input signals are received from the electronic distributor, ambient tempera-
ture sensor, engine coolant, carburetor spark port, and catalyst temperature
sensor. The desired spark advance is computed as a function of engine speed
and load, operating temperatures, and in response to certain transient con-
ditions. In addition, the unit shuts off exhaust gas recirculation for some
operating modes, controls the catalyst by-pass protection system, and pro-
vides warning if malfunction causes the catalyst temperature to exceed
1600 °F.
3.4.2.3 Ford
Improved ignition systems have been under investigation by Ford for a number
of years and this has resulted in the design and preliminary testing of an
electronic ignition system which includes a breakerless type distributor.
Test results have been encouraging and major system components have
successfully undergone extreme stress testing without failure. In addition, a
20 percent improvement in available spark voltage during cold start cranking
has been obtained. This system also provides increased spark voltage to
improve ignition system performance, and indirectly, to reduce exhaust
emission levels.
Current efforts are aimed at confirming initial reliability test results, com-
pleting production cost studies, and determining effects on the emission per-
formance of normally maintained vehicles. Additional studies are being
conducted to explore the use of new magnetic materials and components.
Two systems currently under study are a Ferrosonant capacitor discharge
ignition system and a pulse RF ignition system. Investigations are also
3-10
-------
underway to explore the effect of various spark plug parameters with the
objective of improving the misfire limit at leaner air/fuel ratios.
If its engineering development programs are successful, and if the potential
advantages of this type of system are substantiated by subsequent tests, Ford
plans to incorporate an electronic ignition system of the breakerless type in
future emission control systems.
3.4.2.4 General Motors
General Motors is continuing the development of optimum centrifugal and
vacuum spark calibration and on-off spark timing controls such as those
currently used in production vehicles. An improved electronic ignition system
is also being developed. This system is similar to those currently available
on some models of the 1972 Pontiacs, except that it will have a higher capacity
to allow a wider spark plug gap and a long-duration spark for improved
ignition of lean mixtures. Currently, this improved system is in the
experimental design stage.
Current plans are to phase in the new high-energy electronic ignition system
for full production in the 1975 model year.
3.4.2.5 International Harvester
International Harvester is considering the inclusion of an electronic ignition
system as a part of its future emission control systems. Development in
this area, however, is lagging because of the lack of experimental hardware
from its suppliers. The earliest date anticipated for production is 1976.
3-11
-------
REFERENCES
3-1 American Motors Corporation, Letter to Mr. William D. Ruchekshaus,
Administrator, Environmental Protection Agency, 4 April 1972.
3-2 Ford Motor Company, Technical Data Submittal provided by Ford
at the request of the EPA Suspension Request Hearing Panel,
26 April 1972.
3-3 American Motors Corporation, "Emission Control for 1975-76
Model Years - Light-Duty Vehicles," Status Report, October 16, 1971.
3-4 Chrysler Corporation, "Progress Report to the Environmental
Protection Agency on the Technical Effort Aimed at Compliance
with 1975-76 Emission Standards, Established by the Clean Air Act
of December 1970, " 20 October 1971.
3-5. Ford Motor Company, "1975/1976 Light-Duty Vehicle Emission
Control Program, " Status Report to the EPA, October 18, 1971.
3-6 General Motors Corporation, "1975-76 Emis sion Control System
Status," 11 November 1971.
3-7 International Harvester Company, "Summary of Efforts Directed
Towards Compliance with Clean Air Act as Pertaining to
Automotive Emission," November 1971.
3-12
-------
4. EXHAUST GAS RECIRCULATION
4.1 BACKGROUND
The amount of NO produced by internal combustion engines is related to the
Ji
combustion temperature in the cylinder. At the high combustion temperatures
associated with optimum engine performance, the uncontrolled NO emissions
are typically in the range of 4-6 gm/mi. Within the limitations of acceptable
driveability and fuel economy, this quantity can be reduced appreciably by
the introduction of an inert gas into the combustion chamber to absorb heat
and thereby lower the temperature during combustion. Since the engine
exhaust is a convenient source for an inert gas, systems employing exhaust
gas recirculation (EGR) are generally proposed for the reduction of NO
3C
emissions to the 2-3 gm/mi level.
The lower combustion temperature resulting from the use of EGR causes a
reduction in power output (at the same spark advance setting) which effectively
translates into a fuel economy loss. A fuel consumption penalty of 3 to 5
percent is typical of the loss incurred for the EGR flow rates needed to reduce
the NO emission to the 3.0 gm/mi level required by the 1973-74 and 1975
Federal standards.
EGR also effects vehicle driveability. Concurrent with the reduction in com-
bustion temperature is a loss in pressure, a delay in the initiation of combus-
tion and a decrease in flame speed resulting in a retarded pressure peak. The
net effect is a more pronounced cycle-to-cycle pressure (and torque) variation
which affects the smoothness of operation and/or response ("driveability").
Other noticeable performance effects can be rough idle, stumble during part-
throttle operation, surge at certain cruise speeds, and an increase in full
throttle acceleration time. In general, all of these effects increase in
severity with an increase in EGR flow rate.
4-1
-------
While all of the EGR systems operate on the same basic principle, the desings
of the different manufacturers differ in a number of details. These include
the location of the exhaust gas pick up, the amount of exhaust gas cooling, the
point of introduction of the recycled gas into the engine induction system, the
metering devices, and the modulation signal source and associated control
system. Operational variables include recycle rates and "on-off" program-
ming of EGR to achieve the required emission levels and to accommodate
certain engine operating conditions. >
4.2 REQUIREMENTS FOR 1975
The Federal NO requirements for 1975 are essentially unchanged from those
Jt
of 1973-74 (3. 1 versus 3.0 gm/mi, respectively). The difference, simply
reflects the change in the 1975 test procedures which apply a weighted average
of the hot and cold start emissions. Consequently, most of the automobile
manufacturers plan to continue the production of their current types of EGR
system designs at least through 1975.
To ensure satisfactory performance of the emission control system proposed
for 1975, it is expected that major changes will be made in the carburetion
and ignition systems and their associated controls. These systems signifi-
cantly affect the basic engine characteristics and thus interact, in a complex
fashion, with the emission control systems. These anticipated changes, there-
fore, might well affect the EGR system performance and/or requirements.
Improved carburetion and ignition systems are being developed by most of
the automobile manufacturers, but production versions are not yet available.
As a result, the 1975 emission control system development tests, for the
most part, have been conducted with carburetion and ignition systems cur-
rently in production. The results from these tests, therefore, cannot be
extrapolated to accurately predict the performance of the 1975 EGR-equipped
production systems when all of the engine modifications are included.
4-2
-------
In general, the type of carburetion and ignition system improvements that are
expected should benefit the EGR system. These benefits could be in the form
of improved fuel economy or driveability, which accrue through reduction of
EGR flow rate requirements, or of improved NO emissions at the EGR flow
rates currently employed by some manufacturers. Additional development,
however, will be required to achieve the optimum balance in the projected
1975 emission control systems.
4. 3 INDUSTRY STATUS
At the present time, the 1973 model year vehicles, most of which incorporate
EGR systems, are undergoing or have completed emission control certification.
A common problem that has been experienced during these tests is the limited
durability of the EGR systems. This problem is associated with the plugging
of orifices in the system and/or sticking of the EGR flow control valves.
To alleviate this problem, periodic EGR system maintenance during the 1973
certification tests has been allowed (References 4-1 and 4-2).
The clarification of the allowable maintenance that can be performed on the
EGR system during certification tests will undoubtedly require modifications
to the current EGR system designs of many of the automobile manufacturers.
However, there is no information available at this time to indicate the extent
of the modifications that are being considered.
4-3
-------
REFERENCES
4-1 Aerospace Corporation Report No. TOR-0172(2787)-2, "An
Assessment of the Effects of Lead Additives in Gasoline on Emission
Control Systems which Might Be Used to Meet the 1975-76 Motor
Vehicle Emission Standards," 15 November 1971.
4-2 Letter from E. O. Stork, Director, Mobile Source Pollution Control,
to Dr. F. W. Bowditch, General Motors Engineering Staff,
November 19, 1971.
4-3 Letter from E. O. Stork, Director, Mobile Source Pollution Control,
to Dr. F. W. Bowditch, General Motors Engineering Staff,
December 9, 1971.
4-4
-------
5. OXIDATION CATALYSTS
5. 1 SUMMARY DISCUSSION
*
Emission control systems incorporating catalytic converters containing an
oxidation catalyst are, with one exception (Toyo Kogyo with thermal reactor),
considered by the automotive industry as the "best" or "first-line" approach
for meeting the 1975 Federal HC and CO emission standards for light-duty
spark ignition 1C engine vehicles. Despite intensive experimental evaluation
programs, no one has yet demonstrated that he can meet the 1975 50, 000-
mile emission standards. However, one or more catalyst changes at lower
mileage could permit the manufacturers to meet the 1975 standards.
The problem of meeting the HC and CO standards for a duration of 50, 000-
mile distance is a severe one when viewed from considerations of the inher-
ent characteristics of oxidation catalysts. The alumina substrate or ceramic
substrate with alumina wash coat which supports the active catalytic material
requires a high degree of thermal and mechanical protection to guard against
loss of alumina porosity (essential for high catalytic activity) and against
failure of the ceramic substrate. The catalysts also are very sensitive to
contamination from sources which can reduce or destroy catalytic activity
(e.g., "poisons" such as lead, phosphorus, sulfur, etc.). Despite such
inherent characteristics, several oxidation catalysts have been developed
which merit consideration for integration into 1975-type emission control
systems.
Table 5-1 summarizes typical best emission levels obtained with oxidation
catalysts at low mileage, where the effects of excessive temperature or
contamination have not yet significantly impaired catalyst performance.
Catalysts from 13 different companies are included; the experimental vehicle
systems range from conventional passenger cars to laboratory prototype
1975 systems. As can be noted, many catalysts (base metal or noble metal,
pellet or monolithic) achieve HC and CO levels far below 1975 standards when
5-1
-------
Table 5-1. Summary of "Representative-Best"
Mileage Catalyst Data
Catalyst Mfr. /
Type
APCC (Houdry)
(Base/Pellets)
Am. Cyanamid
(Base/Pellets)
Chemico
(Base/Pellets)
(Noble/Mono)
Testing Co.
Chrysler
Test/
Car No.
259
62505
61318
EPA (Ann Arbor)
Car and/or CID
360
Pontiac 455
Chevrolet 350
System Description
AI
x
x
X
1971 Oldsmobile-350
i
Engelhard
Chrvsler
21/119
351-V8
x
351-V8
351-V8
X
440 x
35/258 GD57E41/360
Volvo j 913/
Am. Motors
GM
Brit. Leyland
SAAB
Ford
OB 54821
DOO-24
61319
3/271
EGR
Mod.
Carb. EFE
X | X
x ! x x
X j X
1
TR
Test
Catalyst Mileage
1975 CVS-CH Emissions
HC
1
30ro Size 1057 JX8-2X1 0 0.23a
1259JX3-1X1
6
! 1259JX3-1X1 0
0. 20/
0.25
: j Two beds j 0. 15
;
x
X
PTX-433 500 . 0. 16
Std. PTX-5 380 0.32
Imp. PTX-5
I
x : 0. 2rc Pt; Oval; 135 in?
x x ; i 0. 35To Pt; Oval
0 0. 22
1268 i 0.23
627
0.23
Model 144; Engine B20B x x PTX-416 0 0.11
232-6
Chevrolet 350
Austin Marina, 110 CID
1.85 Liter
351 Ford- 1, Group I
1A58-D
351 Ford-1, Group III
1971 351 W-2V
x
X
X
X
X
X
X
j
1
PTX-423-S I 0 0.09b
i i
x | x j
X
X
X
X
PTX-4 0 0. 13
| PTX (stackedl | C ; 0. 04
x
x
X
1
Type H
' 0
(2) PIX-5.35 0
(2) PTX- 5. 35, 0
1 PTX-7.35
PTX-5. 35 IRHI
PTX-5. 10 (LH)
0
0
0.43
0. 19
0. 17
' 0.23a
0.1 Oa
a!972 CVS-C test procedure
Least-squares straight line value
CO
3.6a
0.8/
2.9
1.36
0.52
2. 1
0. 28
1.0
0.9
1. 55
1.5°
. '1.9
1.49
2.99
1.91
1.77
3. lla
1.41a
gm/mi
1.21a
1.4
1.9
Remarks
.0.26
Lead Sterile fuel
and ashless lube
oil
<3.0 Lead Sterile, fuel
and ashless lube
oil
<3.0 Lead Sterile fuel
and ashless lube
oil
1.28
5.44 EGR off
2.48
0. 75 1970 type slow
choke
1.3
1.67
0.96
2. 34 Riverside
program
2.26 Riverside
1.27a
program
Cold ^ Ford
emis- 1975
sions Dura-
0.99a
,. bilitv
Hot _
emis- _
Program
sions > B
5-2
-------
Table 5-1. (Continued)
Catalyst M.'r./
Type
W.R. Grace
(Base/Pellets)
W.R. Grace
(Noble/Mono)
Matthey Bishop
(Noble/Mono)
Monsanto
(Base/Pellets)
Oxy-Catalyst
(Base/Pellets)
UOP
(Noble/Pellets)
UOP
(Noble/Mono)
Testing Co.
W.R. Grace
CM
W.R.Grace
Chrysler
Int. Harvester
Johnson- Matthey
Brit, Levland
Volvo
Daimler-Benz
Saab
Saab
GM
GM
UOP
Toyota
Saab
Mitsubishi
Volvo
UOP
Toyo Kogyo
Test/
Car No.
275
2823
1246
300
2/117
161
06B '44443
2180
5/311
9/385
2828
61329
933
2541
602/
OB 44085
Car and/or CID
1970 Impala-350
Buick-455
Cadillac- 500
1971 Chevelle-350
360
1100 D Travelall; V-345
1972 Avenger;
1500 CC Cricket Engine
MGB, 110 CID
1972 Model 144; Engine B20F
W-108
2. 0 liter
1.85 liter
Buick 455
Chevrolet 402
Buick 455
Oldsmobile 350
1971 Chevrolet 350
Toyota 1. 600 liter
Saab 99E; 1.85 liter
1971 Ford 351
1971 Chevrolet 350
Mazda 1.600 liter
System Description
AI
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
EGR
X
X
X
X
Mod.
Garb. | EFE
I
i
I
j
i i
X
X
X
X
X
X
i
j
Elect.
Inject.
X
X
TR
SO"". Size
Catalyst
Test
Mileage
Da vex- 1.42
(300 in."1)
Davex 142
(SMR 7-38811
Davex 117
Davex 502
(51 in.3)
Davex 47V
(2) 3 x 3-1/4 in. Discs
Spiral substrate
AEC 3A
AEC 3A
404
ECA-141
XBP-70194
G-1313
PZ-224-M1
PZ-224-8605
PZ-214
PZ-216
PZ-226
2294-165
PZM-7711
PZM-17122
0
0
126
0
0
0
100
1350
0
2520
0
0
126
0
Q
0
0
0
403
0
0
0
0
1975 CVS -CH Emissions, grr./mi
HC
0. 17
0.20
0.27
0.21
0.40
0.46
0. 11
0. 14
0:72
0. 11
0. 21
0.32
0. 22
0. 14
0.47
0. 19
0. 17
0. 17
0. 07
0.21
0. 19
0. 05
0. 12
0.69
0.38
0.53
CO
3.24
4. 7
1.7
1.70
8.3
5. 1
1.65
1.02
1. 56
4.28
2.34
2. 32
1.44
3.3
4.0
1.8
2.7
0.90
0.73
2.69
3. 15
1.04
1.69
2. 10
1.65
5.00
X0x
2.9
1.01
4. 51
0.85
2.41
3. 32
3:65
1. 14
l.°5
1. 75
2.37
. 1
1. 1
2.4
2. 2
3.77
1.24
Remarks
Lead-Sterile
fuel
Converters empty
at next test
(4-3/4 x 1.7 in.)
Mitsubishi converte
Estimated 1975
CVS-CH orocedure
5-3
-------
Table 5-1. (Continued)
Catalyst Mfr. /
Type
UOP
(Base/Pellets)
Kali-Chemie
(Base/Pellets)
Degussa
(Base/Pellets)
1C!
(Noble/Pellets)
(Noble/Mono)
AC-Delco
(Bass/Pellets)
Testing Co.
UOP
CM
Saab
Daimler- Benz
Saab
Daimler- Benz
CM
British Leyland
British Leyland
AM Motors
Volvo
Int. Harvester
Test/
Car No.
932
61420
7/301
2324
12/301
2377
2826
-
-
Dll-3
732/
OB 50430
393
Car and/or CID
1971 Chevrolet 351
1971 Chevrolet 350
Buick 455
Oldsmobile 455
1. 85 liter
1.85 liter
Buick 455
Austin Marina, 110 CID
Austin Marina, 110 CID
258-6
1972 Model 144
1110 Travelall; V-392
System Description
AI
X
X
X
X
X
X
X
X
X
X
EGR
X
X
X
X
Mod.
Carb.
X
Elect.
Inject.
Elect.
Inject.
X
EFE
TR
Catalyst
PZ-1-214-3
PZ-1-214L- 1
PZ-4-214-R-14
PZ-2-168-R-5
OM 56 ET
Test
Mileage
0
0
0
100
0
0
2580
10
0
0
0
120
0
1975 CVS-CH Emissions, gm/mi
HC
0. 14
0. 04
"0.19
0. 20
0. 22
0. 10
0. 19
0.74
0. 14
0.38
0. 19
0. 18
0.23
0. 24
0.35
CO
1.21
1.00
1.8
2.6
2.85
1.70
2. 11
15.66
2.3
3.5
1.38
'2.29
1.47
2.43
4.56
NO
X
3. 53
2.41
2.4
1.0
1. 02
0.28
1.66
2.52
1.0
3.3
2.08
2.33
2. 12
3. 14
3.11
Remarks
GM converter
GM converter
a!972 CVS Test Procedure
5-4
-------
fresh. However, when the catalysts are operated to extended mileages, the
HC and CO emissions tend to rise to levels exceeding the 1975 standards.
Table 5-2 summarizes typical best high-mileage or durability emission
test data for the same catalysts shown in Table 5-1 at low-mileage conditions.
The emission levels shown in these tables should be read with caution to pre-
vent misinterpretation of the data. Emission test procedures included the
seven-mode, 1972 CVS-C and 1975 CVS-CH procedures, which give different
results and are difficult to correlate for different catalyst systems. Also,
several data points which appeared on the table were based on "hot" test
cycles which give considerably lower values than the corresponding "cold
start" test. The method of accumulating durability mileage also varied,
making any simple comparison difficult. Finally, many of the tests were run
on catalyst test-bed vehicles, while others were run on laboratory prototype
1975 systems.
While a number of these catalysts met 1975 HC and CO standards at greater
than 20,000 miles, the variation of vehicle test procedures (AMA durability
runs, dynamometer runs, etc. ) and the variation in test fuels and oils pre-
cludes a systematic assessment of the true capability of a given catalyst
under projected EPA certification conditions. These conditions encompass
the 50, 000-mile EPA certification test specifications and the use of fuel with
projected additive contaminant levels of 0. 05 gm/gal lead (max. ), 0. 01 gm/
gal phosphorus (max. ), and conventional lube oils. Such an assessment can
be made only with vehicles incorporating the full complement of 1975 emission
control system components, tested in accordance with EPA certification
procedures.
Catalyst durability is composed of two separate but interrelated aspects:
emission durability and physical durability. Emission durability, or the
ability to continue oxidizing HC and CO to the required levels throughout
5-5
-------
Table 5-2. Summary of "Representative-Best" High
Mileage Catalyst Data
Catalyst Mfr./
Type
APCC (Houdry)
(Base/Pellets}
AM Cy ana mid
(Base/Pellets)
Chemico
(Base/Pellets)
Engelhard
(Noble/Mono)
Testing Co.
CM
No data
No data
Engelhard
Chrysler
Volvo
Am. Motors
CM
Brit, Leyland
Ford
Test/
Car Xo.
61318
2233
20X333
12/385
13/698
1091/
OB 44085
DOO-24
61319
17934
1A58-D
Car and/or CID
Chevrolet 350
Oldsmobi'e 455
351-V8
Torino- 351
351-V8
360
360
400
1972 Model 144; Engine B20F
232-6
Chevrolet 350
1971 Buick. 455
Austin Marina, 110 CID
1971 351 W-2V
System Description
AI
EGR
X X
X
X
X
X
X
X
X
X
X
X
;:
x
X
X
X
X
X
Mod.
Carb. -
X
X
X
X
EFE
TR
I
Type H
Catalyst
12S9 JX3-1>11
1259 JX3-1X1
PTX-433
(2) PTX-433-S
Imp. PTX-5
0. 2% Pt; twin
0. 35To Pt
0. ZTo Pt; two 4 in.
PTX-416
PTX-423-S
(0.27o Pt)
PTX-4
(2) PTX-423-S
PTX (stackedl
PTX-5. 35 (RH)
PTX-5. 10 (LH)
Test
Mileage
21, 178
30, 037
35,821
48, 300
12,030
35,943
20, 000
43,000
25, 344
50, 000
21, 527
70, 000
17,000
25,000
1975 CVS-CH Emissions, gnVmi
HC
0.87
0.73
0.35
23 ppm
0.24
0.36a
0.26a
0. 16a
0. 24
0.32b
0.55
0.85
0.63
0.75*.
0.58a
CO
4. 1
10.6
3.0
40 ppmd
2.6
4.7a
2.84a
1.88a
2.45
4.8"" '
5.5
8.7
4.t5
7.97a
7.81a
X
1.6
2.3
<2.2
0.78a
1.56a
3.91a
1.82
* ML
1.6
3.5
1.32
' 1.64a
l.-28a
Remarks
Test continuing
Test discontinued
Lead-free fuel and
ashless lube oil
Commercial lead -free fuel and
standard lube oil
ashless lube oil
Lead-sterile fuel and
ashless lube oil
Replaced monolith wrapping;
temperature kept below 1500°F
Catalyst failed
Converter damaged X.
Catalyst failed at 29, 900 mi
(used 0. 015 gm/gal lead)
1970 type slow choke
70, 000 mi high speed tire test
run at Arizona track
Cold Emissions 1 Ford 1975
I Durability
8
5-6
-------
Table 5-2. (Continued)
Catalyst Mfr. /
Type
W.R. Grace
(Base/Pellets!
(Noble/Mono)
Matthey- Bishop
(Noble/Mono)
Monaanto
(Base/Pellets)
Oxy-Catalyst
(Base/Pellets)
UOP
(Noble/Pellets)
(Noble/ Mo no)
UOP
(Base/Pellets)
Testing Co.
CM
Int Harvester
Johnson-Matthey
Saab
CM
CM
UOP
Mitsubishi
UOP
UOP
CM
Test/
Car No.
1450
161
9/385
61329
472
61317
2850
2541
933
BAK
Car and/or CID
Opel 1. 9 liter
1100 D Travelall; V-345
1972 Avenger
1500 CC Cricket engine
1.85 Liter
Chevrolet 402
Buick 455
Chevrolet 350
Oldsmobile 455
Oldsmobile 350
1971 Ford 351
1971 Ford 351
1971 Chevrolet 351
Buick 455
Buick 455
System Description
AI
X
X
X
X
X
X
X
X
X
X
X
EGR
X
X
X
X
X
X
X
Mod.
Carb.
X
Elect.
Inject.
X
X
X
*
EFE
TR
Catalyst
Davex 117
Spiral substrate
AEC 3A
404
NBP-70194
ECA-125
G-623-71
PZ- 195 (in 2 mini-
verters; 4-3/4 x
1.7"; 30 in.Vbank)
PZ-216
2294-165
PZ-1-214-3
PZ-4-214-R-14
PZ-4-214-R-14
Test
Mileage
23, 000
16,000
24, 000
9, 750
5, 550
27,600
45,500
32,014
18,000
10, 245
21,933
25, 086
7, 000
8, 000
12, 500
7, 180
7. 722
15, 875
46,301
12.980
1975 CVS-CH Emission, gm/mi
HC
1.2
CO
22.9
0.46 6.85
0.33
0.50
0.55
0.37C
0.53C
1.20
0. 58
0.91
0.47
0.74
0.25
1.07
0. 15
0.06
0.30
0.73
0.36
1. 33
2.97
8.8
2.42C
3.52=
13.6
7.4
9.5
2.65
2.46
4.33
1.59
5.25
1.15
2.90
11.7
6.6
NO
X
2. 5
3.99
2.01
2.87
1. 1
3.44C
4.0C
1.4
2.7
2.3
2.52
2.48
3.00
' 2. 1
1.6
Remarks
Lead-Sterile
fuel
Est. 1975 CVS-CH
20-257« catalyst lost
Hot only
Screen failure
Hot only
After 1550 °F
recycling of bed
temperature
More recycling
5-7
-------
Table 5-2. (Continued)
Catalyst Mfr./
Type
Kali Chemie
(Base/Pellets)
1C I
(Noble/Pellets)
(Noble/.Mona)
AC-Delco
(Base/Pellets)
a!972 CVS Test F
Testing Co.
Saab
Brit. Leyland
Brit. Leyland
Am. Motors
Int. Harvester
Test/
Car No.
7/301
D17-11
393
Car arid/or CID
1.85 Liter
Austin Marina, 110 CID
Austin Marina, 110 CID
Z58-6
1110 Travelall; V-392
System Description
Al
X
X
x
EGR
X
x
Mod.
Carb.
Elect.
Inject.
EFE
b c d
q f
TR
Catalyst
Test
Mileage
5,900
9,200
4,500
32,000
20, 000
1975 CVS-CH Emissions, gm/mi
HC
0.25
0.20
0.25
0.51b
0. 51
CO
3.63
2.61
1. 14
3.4b
8. 76
NO
X
1.96
2.21
2.44
1. 9b
3. 00
Remarks
5-8
-------
50, 000 miles, is most strongly impacted by decremental changes in
catalytic activity or efficiency caused by:
a. Contamination from fuel and oil additives or compounds
(e.g., lead, phosphorus, sulfur, etc.1) resulting in
"poisoning" of the catalytic material
b. Reduced alumina porosity due to phase change at excessive
temperature
c. Alumina thermal shrinkage due to excessive temperature
Physical durability, or the ability to maintain the substrate intact throughout
50, 000 miles, is most strongly impacted by
a. Thermal expansion differences between monolithic ceramic
substrates and their supporting container
b. Local melting of monolithic ceramic substrates due to
overtemperature
c. Failure of pellet retaining screens due to overtemperature
d. Cracking of monolithic ceramic substrates and breakup of
pellet substrates due to vibratory loads
*
In addition to loss of emission control, physical failure of either monolithic
or pellet catalytic converters due to either overtemperature conditions or
rupture of the canister can cause vehicle fires, posing a serious vehicle
safety hazard.
A number of solutions to the above oxidation catalyst problem areas are
currently under active consideration or development by the Federal Govern-
ment, the catalyst suppliers, and the auto makers, as follows.
a. Fuel additive regulation. The Administrator of EPA is
currently proposing to regulate the level of lead (0. 05 gm/gal
max. ) and phosphorus (0. 01 gm/gal max. ) in gasoline to
reduce the effects of these catalyst "poisons" to hopefully
tolerable levels.
b. Qvertemperature protection. Various methods of thermal
control are being developed by the auto makers.to protect the
catalyst from overtemperature conditions. In one system,
5-9
-------
control is effected by precise regulation of engine exhaust
conditions at the inlet to the catalyst bed. In another pro-
posed system, control is effected by bypassing the catalyst
bed when the exhaust gas HC and/or CO level or temperature
is excessive. ' ' "'
c. Improved catalyst properties. The catalyst suppliers are
improving both the physical strength and activity of their
catalysts.
d. Improved catalyst containers. Both catalyst suppliers and
auto makers are developing catalyst containers with improved
de&ign features to overcome thermal differential expansion
and vibration effects.
The proposed innovations and development activities described above reflect
a technology that is rapidly changing through intensive product design modi-
fications, as well as through comprehensive test and evaluation programs in
both the catalyst industry and the automotive industry. Because of these
rapid changes, the activity and durability data frequently reported as latest
results are based on catalyst materials and substrates which may in fact be
"old technology" previously discarded by others. Due to the time delay
inherent in the relationship between the substrate-catalyst-converter suppliers
and the auto makers themselves, it is not surprising that some problems
reported as severe by one company are treated as solved by others. Some
recent data presented by the catalyst makers with their latest technology have
indicated encouraging results at relatively high mileage; however, it remains
to be seen whether these catalysts can maintain good performance when
tested in a prototype emission package under realistic driving conditions by
the auto manufacturers.
5.2 CATALYST TYPES
A catalytic converter is a device containing a catalyst material
which promotes chemical reactions which would otherwise occur
very slowly. Those catalysts which promote the oxidation of HC and
CO into carbon dioxide (CO2) and water (H.,0) are referred to as "oxidation
catalysts, " "HC/CO catalysts, " or "HC/CQ oxidation catalysts. " A great
5-10
-------
effort has gone into developing this type of catalyst for automotive application
and literally hundreds of combinations have been tested, including base
metals, precious metals, and combinations of both. The HC/CO oxidation
catalysts, as the name implies, require excess oxygen (air) to convert the
HC and CO to H?O and CO?. This can be accomplished by operating the
engine at lean air-fuel mixtures or by adding secondary air to the engine
exhaust upstream of the catalyst. To date the latter approach has been used
almost exclusively.
Both base metal and noble metal catalysts are under intensive evaluation and
development by the automobile industry. Specific configurations of catalysts
and catalytic converters vary widely. One approach is to use a monolithic
coated substrate contained in a cylindrical shell. Another approach is to use
a pelletized form of catalyst held in place by interior louvered members,
within an outer container. In general, the specific structural and chemical
formulations are considered trade secrets by the catalyst suppliers. Neces-
sary attributes for catalytic converters for automotive use include sufficient
chemical activity, long life, resistance to mechanical shock, and high-
temperature capability.
5.2.1 Typical Catalysts
Hundreds of catalyst types have been examined for possible use in controlling
automotive emission of HC and CO. Usually, these catalysts were first tested
in laboratory-scale experiments, with the more promising ones then tested
in engine dynamometer tests and, finally, in vehicle road tests.
5.2.1.1 Base Metal Catalyst
Base metal catalysts employ metals or oxides of metals from the transitional
group of the Periodic Table of Elements which includes vanadium (V),
chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper
(Cu), and zinc (Zn). Several metals and their oxides are usually combined to
form a catalyst (e.g., Cu-Cr, Cu-Mn). Supports such as alumina
5-11
-------
and/or silica (SiO,,) are used to provide structural strength. Notice that a
few base metal catalysts also incorporate trace amounts of noble metals such
as platinum (Pt) or palladium (Pd).
5.2. 1.2 Noble or Precious Metal Catalysts
The noble or precious metal catalysts that have been tested are primarily Pt
and Pd. They are deposited on Al-O,, SiCU, or cordierite supports (see
Section 5.4) and are characterized by relatively low concentrations of active
metal (approximately from 0. 1 to 0. 6 percent by weight). In general, an
alumina or promoted-alumina "wash coat" is applied to the substrate prior to
the deposition of the noble metal on monolithic cordierite substrates.
5.2.2 Automotive Catalyst/Substrate Combinations
Most catalyst suppliers and/or automotive users refer to a catalyst type by.
substrate (or support) type, in addition to the type of catalytic material
involved. The substrate is the material on which the active catalyst compo-
nent (and wash coat, when used) is coated, and can be either a pellet, or a
monolithic structure.
The pellet (or bead, or particulate) type of substrate consists of small
individual alumina (A1_O,) pellets which can be of a variety of shapes ranging
from spheres to elongated cylindrical rods. They are generally small in
cross-section or diameter (approximately from 1/8 to 3/16 inch), thus
requiring many such pellets for a catalytic converter.
The monolithic type of substrate refers to a single unit structure or package,
generally of honeycomb configuration to provide the necessary surface area
for chemical reactions. While referred to as monolithic, the structure may
in fact be composed of layers of corrugated material stacked together to
comprise the entire monolithic unit. Such structures are usually composed
of cordierite materials.
5-12
-------
The following catalyst/substrate combinations are those reported to be of
principal interest for automotive HC/CO oxidation catalytic converters: base
metal/pellets, noble metal/pellets, and noble metal/monoliths.
A fourth possible combination, base metal/monolith, apparently is not under
active development or consideration. General Motors has stated that a
suitable base metal/monolith catalyst has not been made available by catalyst
suppliers. ; , ; '
5.3 SPECIFIC CATALYST FEATURES (BY COMPANY)
The follpwing sections briefly describe the known characteristics or design
features of specific catalysts supplied to the automotive industry by the
various catalyst suppliers for evaluation. Such definitions are limited to the
extent disclosed in the recent EPA 1975 Suspension Hearings or as disclosed
in communications between the catalyst manufacturers and the Division of
Emission Control Technology, EPA, Ann Arbor, in April 1972.
Table 5-3 is a brief summarization of the catalyst suppliers and their
products, as discussed below.
5. 3. 1 Air Products and Chemicals, Inc. (Houdry Division)
The Houdry Division of Air Products and Chemicals, Inc. has been principally
concerned with developing base metal/pellet catalysts .(Ref. 5-1). It has
supplied four different catalysts of this type (designated A, B, C, D) to the
AC-Delco Division of General Motors and two other catalysts (E and F) to
Chrysler Corporation. .
While its catalysts are designated base metal, sorrie are promoted with small
concentrations of precious metal.
It is not clear whether Houdry fabricates the pellet or hot. It apparently has
been involved in a program of improving the pellet durability properties,
however this could relate to thermal and other treatments instead of direct
pellet fabrication from raw materials.
5-13
-------
Table 5-3. Potential Catalyst Suppliers
Company
UOP
Oxy- Catalyst
Matthey- Bishop
W.R. Grace
Engelhard
Monsanto
American Cyanamid
Chemico
APCC (Houdry)
Union Carbide
Kali-Chemie
Degussa
ICI
Products
Base
Metal
Pellets
X
X
-
Davex 142
-
X
X
X
X
Noble Metal
Pellets
X
-
-
-
-
Monoliths
-
X
Davex 502
(PTX Series)
Catalytic metal choice unknown.
Support would be flexible fibers
in various forms (tow, yarn,
felt, monoliths)
X
X
Supplied To
U.S. auto companies and many
foreign manufacturers (includ-
ing Volvo), GM (and others)
4 U.S. and 20 foreign auto
manufacturers
GM, Ford, Chrysler, and
foreign manufacturers
Most auto companies
Saab, Chrysler, GM
GM
None (Tests at GM)
AC-Delco (A, B, C, D)
Chrysler (E, F)
"
Saab, Daimler-Benz
Saab, Daimler-Benz, GM
Brit. Leyland
Remarks
Noble metal pellet
(spherical) is UOP's
first choice
Under supply contract
to Ford
Claim recent thermal and
attrition improvements
Consultant role only
Some promoted with
small amounts of
precious metals
Not targeted for- 1975 use
(developmental only)
Noble metal pellet or
monolith.
-------
5.3.2 American Cyanamid
Automotive catalyst development efforts of American Cyanamid have been
concentrated on base metal/pellet catalysts (Ref. 5-2). It is known to have
supplied such catalysts to General Motors, and may have supplied others.
Cyanamid claims to have made recent improvements in thermal stability and
attrition characteristics of their catalysts.
Cyanamid has no real position in the monolithic catalyst area.
5. 3. 3 Chemico
Chemico is not a commercial producer of catalysts (Ref. 5-3). However,
it has been developing an emission control system which incorporates a base
metal/pellet catalyst. Its position is that it is trying to develop a technology
and would plan to market that technology to other companies as a consultant.
Chemico has had discussions with the four major domestic automobile manu-
facturers and with a number of suppliers. To date, Chemico has signed
testing agreements with GM, Chrysler, and Ford.
5.3.4 . Engelhard Industries
Engelhard's principal automotive oxidation catalyst product is the exhaust gas
purifier tradenamed "PTX" (Ref. 5-4). In brief, PTX is a noble metal
(platinum)/monolith catalyst. As supplied in the past it is cylindrical,
although there is no reason it could not be (and may be) provided in other
shapes (e. g. , oval, square, etc. ). The monolithic substrate utilized to date
has been the corrugated ceramic produced by American Lava (tradenamed
"ThermaComb") in both stacked (laminated) and spiral (rolled-up) configura-
tions. Again, the Corning monolithic substrate (designated W-l) could be
used as well.
Engelhard has supplied PTX automotive catalysts to a number of domestic
and foreign auto manufacturers for evaluation. In general, most of these
5-15
-------
have been of the standard PTX design (e.g., PTX-433, PTX-433S, PTX-5,
PTX-423S, etc.)- Engelhard also claims an improved PTX catalyst which
has better high temperature stability and light-off temperature characteristics,
' " .*' '
Englehard is currently under contract to Ford for PTX catalyst supply (with
the American Lava "ThermaComb" substrate).
5.3.5
W.R. Grace and Co.
W.R. Grace and Co. has developed two oxidation catalyst types and supplied
them to automobile manufacturers for evaluation (Ref. 5-5). One is a base
metal/pellet catalyst (Davex 142) that employs an alumina support material
not commercially available (fabricated by Grace). The other is a noble metal/
monolith catalyst (Davex 502) which employs a unitary ceramic support. The
monolith supports used by Grace to date have been those commercially avail-
able from American Lava and Corning, and developmental supports provided
by an outside supplier and an internal Grace research program.
Grace has supplied catalyst samples to GM, Ford, Chrysler and a number of
foreign manufacturers.
Grace indicates the costs for their products shown in the following table:
Code Name
Type Catalyst
Cost to Automotive Companies
Davex 142
Base Metal Pellet
Davex 502
Noble Metal Monolithic
(2)
$1 - $1.25/lb
@ -7-1/2 Ib
$7.50 - $9.50 per unit(1)
$11 - $13 per unit(3)
(1).
(2)
(3)
one unit per car
0. 026 oz Pt and 0.026 oz other noble metal per converter.
two units per V-8 engine, one for 6-cyl engine.
5.3.6
Matthey Bishop, Inc.
Matthey Bishop is a wholly owned subsidiary of Johnson-Matthey & Co. , Ltd.
Its principal automotive catalyst product is a noble metal (platinum)/monolith
5-16
-------
developed by the Matthey Bishop Research Laboratories, Malvern and the
Corporate Research Center, Wembley, England (Ref. 5-6). Its most recent
catalyst product is designated the "AEC 3A" oxidation catalyst. It is collab-
orating with four US auto manufacturers and twenty British, European, and
Japanese manufacturers.
Matthey Bishop feels its noble metal /monolith unit does not use excessive
platinum (0.04 oz/unit; two units required for a V-8 engine) and would have
reasonable cost ($ 10-$ 15/unit without container) to automobile manufacturers.
5.3.7 Monsanto
It is known that Monsanto has provided base metal/pellet catalysts to some
auto makers. However, no information from Monsanto was available for
consideration.
5.3.8 Oxy-Catalyst, Inc.
Oxy-Catalyst has manufactured and installed many thousands of catalytic
exhaust purifiers on all types of industrial vehicles powered by 1C engines
(forklift trucks, etc.). Its principal products were OC-100 (the tradename
for their pellet purifier) and Oxy-Cat (their platinum/monolith unit).
For automotive application it is most seriously considering base metal/pellet
catalysts and has been supplying GM through the AC Spark Plug Division. It
has supplied 76 of the 368 base metal pelleted formulations tested by GM
(Ref. 5-7).
Oxy-Catalyst has given GM a price quotation of about $1 per Ib (6 Ib/converter).
The pellet alumina substrate is obtained from outside vendors from among
Reynolds, Kaiser, Alcoa, and Pechiney.
5.3.9 Union Carbide Corporation
Union Carbide is in the developmental stage of automotive catalysts employing
a proprietary ceramic fiber as a catalyst support (Ref. 5-8). These flexible
fibers can be prepared in a multitude of forms, such as yarn, felt, tow, and
5-17
-------
various monolithic structures. Union Carbide has not identified any choice or
restriction as to base or noble metal catalytic material.
Union Carbide does not expect to have a viable catalyst entry until 1976;
therefore, it is not a contender for 1975 systems.
5.3.10 Universal Oil Products Company
The Purzaust group of UOP has developed three different oxidation catalyst
candidate's for use in 1975 (Ref. 5-9). They are base metal/pellets, noble
metal/pellets, and noble metal/monolith.
Currently UOP has working programs with the U.S. and many foreign auto-
mobile manufacturers on the development of catalysts and catalytic converters,
One new UOP development is the Mini-Verter. This is a small (30 in ),
simple, and reportedly inexpensive converter charged with a small quantity
of highly active catalyst material designed to operate at elevated tempera-
ture levels. Universal Oil Products Co. believes the noble metal spherical
pellet catalyst offers the most promise in automotive application.
5.3.11 Miscellaneous
A number of other potential catalyst suppliers (e.g. , Kali-Chemie, Degussa,
ICI, etc.) have products which are not described herein due to a lack of
detailed information.
5.4 SUBSTRATE AND CONVERTER DESIGN FEATURES
5.4. 1 Substrate Features (By Company)
The following sections briefly describe the known characteristics or features
of specific catalyst substrates supplied to the catalyst suppliers by the sub-
strate producers. Such definitions are limited to the extent disclosed in the
recent EPA 1975 Suspension Hearings or as disclosed in communications
between the substrate manufacturers and the Division of Emission Control
Technology, EPA, Ann Arbor, in April 1972.
5-18
-------
Table 5-4 is a brief summarization of substrate suppliers and their products,
as discussed below.
5.4.1.1 Alcoa
Alcoa has supplied alumina pellet substrates to catalyst manufacturers for
catalyst preparation (Ref. 5-10). Alcoa both mines and processes alumina ore.
Alcoa already manufacturers pellets for nonautomotive catalyst preparations
and has supplied these and modified pellets to various catalyst manufacturers.
Alcoa has contacted 13 firms with whom it has been working. To date, Alcoa
has not produced a satisfactory catalyst substrate and has been unsuccessful
in obtaining Low density, High thermal stability, Pellet strength, and Effective
catalyst life.
Alcoa does not feel that it can produce a successful substrate pellet although
it has been trying to do so for 18 months. Alcoa feels the catalyst companies
will make their own pellet. However, Alcoa does hope to supply alumina
powder to catalyst manufacturers to make their own pellets. Alcoa could
also play a role in supplying whatever alumina was needed for ceramic
monolith substrates.
5.4. 1.2 American Lava Corporation
American Lava has produced honeycomb and split-cell type corrugated
ceramic catalyst supports (tradenamed "ThermaComb") for ten years
(Ref. 5-11). ThermaComb substrates, until the very recent availability of
the Corning W-l substrate, have been the principal monolithic substrates used
in noble metal/monolith catalysts evaluated for automotive application (e. g. ,
Engelhard, Matthey Bishop catalysts).
The two ceramic compositions_xurrently available in corrugated structures
(R i iR I
are alpha alumina, Al Si Mag>'614 and 776, and cordierite, Al Si Mag\_y795.
The two alumina bodies differ only in the porosity level and physical properties
that are affected by porosity as shown in Table 5-5 (Ref 5-11).
5-19
-------
Table 5-4. Potential Catalyst Substrate Suppliers
Product
Company
UOP
Union Carbide
Reynolds
Kaiser
W. R. Grace
Corning
American Lava
Alcoa
Raw
Materials
Ceramic
Tow, yarn, felt
fibers
(flexible)
Alumina
powders
Alumina
powders
Pellets
X
X
(Alumina)
X
(Alumina)
X
(Alumina)
Monoliths
X
X
-
-
(Development
item)
X
(Cordierite)
X
(Cordierite)
Remarks
For own catalyst use only
Not targeted for 1975 use
(developmental only)
Can supply in quantity at
$0.41/lb
Would supply both raw
materials and pellets
For own catalyst use only
Recent entry in monolith
substrate field
Principal substrate used to
date for noble metal /monolith
catalysts
Will not manufacture sub-
strate - suppliers of raw
materials only
-------
Table 5-5. Alumina Body Physical Properties
Materials:
Property
Water Absorption
Safe Operating
Temperature
Specific Gravity of
Material Web
Specific Heat
Coefficient of
Thermal Expansion
Thermal Shock
Resistance
Compressive Strength
(Parallel to Passages)
Modulus of Rupture
Thermal
Conductivity
Unit
%
%
Btu/lb. °F.
in. /in. /°F.
70-1400°F.
Psi (5c/in. SC)
0.016 Thick Web
Psi (4 in. Centers,
1 in. x 1 in. Beam,
5c/in. SC)
Solid Ceramic @ 570°
Btu in. /hr. ft. Z °F.
Alsimag 614
Alsimag 776
Dense 96% Alumina Porous 96% Alumina
Highest mechanical
strength. Good
corrosion resistance.
0
1538
2800
3.65
0.21
4. 4 x 10'6
Fair
15,500
2,800
F. 119.0
For catalyst
carriers and
special applications.
17
1200
2192
2.5
0.21
3.9 x.10"6
Good
8,500
1,500
85.0
Alsimag 795
Cordierite
Good thermal shock
resistance. Excellent
as catalyst carrier.
25-30
1200
2192
1.7
0. 19
2. 1 x 10"6
Excellent
2,750
1,800
10
(Jl
-------
Cordierite is the mineralogical name for the ternary oxide 2 MgO-2Al._O,' 5
/R\
SiO_ and this compound is the primary constituent in Al Si MagV_y795.
The basic differences between the split cell and honeycomb structures are
shown in Figure 5-1. Also pictured is the cross-flow split cell design,
the crisscross split cell, and the crisscross honeycomb.
Two basic forming methods are used to make the corrugated products,
stacking and rolling. They are illustrated in Figure 5-2. The rolled struc-
(R i
tures are available only in Al Si MagV^/795, split cell configuration.
The stacked structures were those first used by the catalyst makers in
developing noble metal/monolith units, then rolled structures were utilized.
More recently, the catalyst makers (e.g. , Engelhard, Matthey Bishop) have
reverted to the use of the stacked structures.
American Lava will be one of the monolith suppliers for Ford (via Engelhard),
and has been in contact with Matthey Bishop, W. R. Grace, and Universal
Oil Products.
5.4. 1.3 Corning Glass Works
Corning Glass Works has concentrated on the development of a monolithic
multicellular ceramic substrate for use as a catalyst carrier (Ref. 5-12). It
has invented a process which allows it to form the ceramic substrate in a
wide variety of shapes. The product is truly monolithic, since it is made all
at one time, and it is made by a process that is fast and precisely controllable.
This product, called W-l, was introduced to catalyst and automobile manu-
facturers in December 1971. Catalyst companies have been able to apply
catalysts to this substrate without difficulty. To date, tests have shown that
catalytic activity and durability are equal to that of other acceptable supports.
Coming's cordierite ceramic monolithic substrate material is different from
conventional monoliths. It may be easier to make and the cross-sectional
shape of the monolith can be easily varied. Corning is quoting between 5£
5-22
-------
: ' SC SPLIT CELL (Note Separator)
Nfe H".
xxsc
CRISS-CROSS,
SPLIT CELL'
'Note separators
.and. corrugations
* at 45°
CRISS-CROSS,
HONEYCOMB
with corrugations
at 45°
Note there is no
separator.
Figure 5-1. Corrugated Structure Types
5-23
-------
RpUJID. STRUCTURES
Figure 5-2. Stacked and Rolled Corru-
gated Structures
5-24
-------
and 5-l/2£ per cubic inch for this material to Chrysler and Ford, and assumes
that approximately 100 cu in. per vehicle will be sufficient for a total sub-
strate cost of $5.00 to $5. 50. The cost of the substrate is somewhat influ-
enced by volume; less so, within limits, by its shape. Limited durability data
are available from Corning. The automotive manufacturers also have this
data. Corning feels their material has mechanical properties superior to that
of their competition.
Corning claims that the material from which it makes the substrate will
present "absolutely no supply problems. " The Corning substrate is
being considered for use by one or more of the following catalyst
firms: Johnson Matthey, Engelhard, Grace, Monsanto, Houdry,
and/or Universal Oil Products.
Information provided by Johnson-Matthey (Ref. 5-13) on Corning W-1
substrate properties is given in the following listing:
Designation Corning W-l
Composition Cordierite
Type Glass Ceramic
Configuration Rectangular Grid
Wall Thickness (in) 0.009
Open Area (percent) 74
2 3
Superficial Surface Area (ft /ft ) 720
Bulk Density (lb/ft3) 28
Expansion Coefficient (per F x 10 ) 12.2
Axial Crush Strength (psi) 7000
Porosity (percent) 31
Max. Service Temperature (°C) 1200
Wash Coat Yes
Metal Area (m /gm Total Metal 0. 17
+ Wash Cost + Support)
o
Surface Area (m /gm Total Metal 18-20
+ Wash Coat + Support)
5-25
-------
5.4. 1.4 W.R. Grace
As mentioned in Section 5.3-5, W.R. Grace manufactures its own alumina
pellet for their Davex 142 base metal/pellet catalyst. Grace also has an
in-house developmental monolithic support which may be used for its Davex
502 noble metal/monolith catalyst (Ref. 5-5).
5.4.1.5 Kaiser Chemicals
Kaiser Chemicals is a producer of basic alumina materials and a supplier
of formed (or beaded) pellet catalyst substrates (Ref. 5-14). Three Kaiser
products have now undergone various stages of performance evaluation;
namely, catalyst substrate alumina powder, type "sa", catalyst substrate
alumina spheres, type "sas", and catalyst substrate alumina spheres, type
"sp". Both the "sa" and the "sas" materials are now being produced on a
commercial scale. The type "sp" material is still in a developmental stage
in that it has not been produced in plant scale equipment. This new product ,
if satisfactory, offers cost savings compared to types "sa" and "sas"
substrates.
5.4.1.6 Reynolds Metals Company
Reynolds is a major producer and marketer of chemicals generally associated
with the production of aluminum metal. Although aluminum melts at 1200 F,
the oxide of aluminum (Al_O,, or alumina) is a very stable substrate material
capable of withstanding 3500°F temperatures while remaining relatively
chemically inert. It can be heat treated so that it has a large interior surface
area, which is a necessary attribute for pellet substrates.
Reynolds Aluminum Research Division has developed supports which are of
interest to several of the catalyst manufacturers (Ref. 5-15).
5-26
-------
Reynolds to date has two major pellet candidates which have adequate
durability and attrition resistance as determined by bench scale testing.
Reynolds feels its pellets are performing satisfactorily in vehicle durability
tests. However, Reynolds recognizes that subsequent treatment of its pellets
by the catalyst manufacturers changes physical durability characteristics of
the pellet. These changes make durability data supplied by the automobile
or catalyst manufacturers more meaningful than data from Reynolds. Reynolds,
therefore, cannot state whether the durability of its support is sufficient for
an acceptable catalyst.
Reynolds does have the ability to supply these supports in necessary quantities
and has quoted price estimates of $0.41/lb.
Reynolds has supplied samples to the firms with which they have active
working agreements. These are W. R. Grace, Engelhard, Air Products and
Chemicals, Monsanto, and Oxy-Catalyst.
5.4.1.7 Union Carbide
As mentioned in Section 5.3.9, Union Carbide is developing a proprietary
ceramic fiber for catalyst support application. These flexible fibers can be
prepared in a multitude of forms, such as tow, yarn, felt, and various
monolithic structures. This material would be applicable to both base and
noble metal catalysts. These supports are not expected to be sufficiently
well developed for 1975 oxidation catalyst use, but may be a 1976 support
contender.
5.4.1.8 Universal Oil Products
Universal Oil Products (UOP) has conducted research and development of both
spherical pellet substrates and monolithic substrates (Ref. 5-9). If UOP
produced such substrates, presumably it would be for its own finished
catalyst product and not for supply to other catalyst makers.
5-27
-------
5,4.1.9 Miscellaneous
Matthey Bishop has reported (Ref. 5-13) that it has examined some alternatives
to the ThermaComb and W-l monolith substrates, including the following:
a. A reaction bonded silicon nitride (Si,N.) honeycomb similar
in configuration to ThermaComb. It does not require a wash
coat (to promote at least short term activity) and has a higher
light off temperature and lower conversion efficiency than
ThermaComb or W-l. The material is also stated to be too
expensive for other than experimental use.
b. A rigid fibrous form of alumina, Fibral 80, which does not
require a wash coat. Although Fibral 80 is remarkable for
an ultra-low light off temperature, it suffers from relatively
low conversion. The conversion problem is attributed to an
ineffective configuration which the manufacturer is currently
modifying.
c. Monoliths recently have become available in development
quantities from Champion Spark Plug, Hexcel Corporation,
. and Owens-Illinois. No data on these designs are yet
available.
5.4.2 Converter Design Features (By Company)
5.4.2. 1 AC Division, General Motors
In the recent EPA Suspension Hearing testimony, GM (Ref. 5-16) indicated
that its AC Division had primary responsibility for catalysts and that the
Oldsmobile Division was the lead division for converter development. How-
ever, other companies utilizing or testing such GM-supplied catalytic con-
verters refer to them as AC or AC-Delco converters.
The AC converter is comprised of a pancake-shaped canister, shown in
Figure 5-3, which houses pelletized catalysts. The exact mechanical
interior features are not specified, but would necessarily include either a
louvered interior pellet-holder or a screen-retainer arrangement for holding
the pellets.
5-28
-------
AIR INJECTION
PUMP
QUICK HEAT
MANIFOLD (EFE)
IMPROVED CARBURETION AND CHOKE
ALTITUDE COMPENSATION
DECEL THROTTLE CRACKER
EXHAUST GAS
RECIRCULATION
TRANSMISSION
CONTROLLED
SPARK
-CATALYTIC
CONVERTER
PCV VALVE
UNITIZED
IGNITION
Figure 5-3. AC Pancake Converter Installation
-------
General Motors indicates the canister will be fabricated of a new
nonnickel-containing steel, GM-6125-M, which was developed by the steel
companies expressly for GM.
5.4.2.2 Chrysler
Chrysler (Ref. 5-17) has utilized a number of converter types in evaluating
catalysts, including the GM (AC or AC-Delco) pebble-bed converter, a
cylindrical monolith converter, a dual cylinder monolith converter, and an
oval monolith converter.
The cylindrical monolith converter is shown in Figure 5-4; the dual cylinder
monolith converter in Figure 5-5; the oval monolith converter in Figure 5-6.
In general, all have metal (stainless steel) containers which house the
monolithic catalyst element and any retaining or support elements; e.g. ,
wire support mesh between monolith and container.
Chrysler has tested a number of pellet type catalysts with the "GM pebble -
bed" converter, including W. R. Grace Davex 45 V, Monsanto EGA 302,
W. R. Grace Davex 137, Houdry (Air Products & Chem. ) 1057JXB-2X1, an
American Oil Co. Catalyst, and a UOP Three-Way Catalyst.
Cylindrical monolith converter tests have utilized Engelhard PTX and
W. R. Grace Davex 47 V catalysts.
Oval monoliths have apparently been limited to Engelhard PTX catalysts.
At least one of these incorporated the new Corning W-l substrate, in that
it was referred to as "extruded" substrate.
5.4.2.3 Engelhard
In addition to providing the bare monolithic catalyst core element (i.e. , PTX
element), Engelhard also will provide a canister for containment of this
element. Engelhard has a patented proprietary core containment device or
arrangement to provide mechanical support for the ceramic core element
5-30
-------
I
UJ
Figure 5-4. 'Chrysler Cylindrical Monolothic Converter
-------
Ul
Ji
N
*
CAR # 385
23,000 MI. @ P.G.
A. M. A. ENDURANCE TEST
ENGELHARD PT. CATALYST
.35% LOADING
4 BISCUITS 4.00 O.D. X 3'
REMOVED 11/24/71
Figure 5-5. Chrysler Dual Cylinder Monolithic Converter
-------
304 STAINLESS
STEEL CONTAINER
EXHAUST GAS
FROM ENGINE
MONOL FHIC CATALYST
ATALYST
MPERATURE
SENSOR
EXHAUST GAS TO
BYPASS VALVE
304 STAINLESS STEEL
WIRE SUPPORT MESH
SECTION THRU CONVERTER
Figure 5-6. Monolithic Catalytic Converter
-------
(Ref. 5-18). Presumably this involves the use of wire mesh and/or crimped
wire located between the core and the canister.
A more recent addition is the use of a small pin extending through the stain-
less steel canister into the mesh which goes around the core element to
prevent rotation of the core within the canister housing (Ref. 5-18).
5.4.2.4 Ford
Ford has tentatively selected the Engelhard PTX (noble metal/monolithic)
catalyst for initial use, employing the American Lava ThermaComb substrate
(Ref. 5-19). UOP, Matthey-Bishop, and W. R. Grace are other contending
catalyst suppliers.
In all cases, it would appear that Ford would retain responsibility for pro-
duction of the catalyst container. No details have been provided concerning
canister design, materials, or ceramic core support techniques. In outward
appearance, however, the design would resemble the Engelhard cylindrical
PTX units.
Ford has also utilized test converters provided by Arvin Industries for
pelletized catalysts. Arvin is also designing containers for monolith converter
evaluations.
The Walker Manufacturing Company has also provided Ford with converters
of the radial flow and downflow types for pelletized catalysts. Converter work
with Walker is continuing.
5.4.2.5 Johns on-Matthey
Johnson-Matthey, in addition to producing noble metal/monolith catalysts
has also supplied the converter outer shell or canister to the auto industry
for limited test purposes (Ref. 5-13).
5-34
-------
Johnson-Matthey originally produced a rectangular canister box containing
two ceramic blocks, each 3-inches long. The canister had the edge seams
welded. This type of catalyst core containment was discontinued due to weld
seam cracking and attrition between the interfaces of the two ceramic blocks.
Johns on-Matthey now provides converters with the following design features.
a. Six-inch deep ceramic blocks
b. A ceramic tape cemented to the exterior of the catalyst block
c. A fire hardened cement at the periphery of the inlet and exist
faces to prevent attrition on the securing frames.
d. Crimped wire mesh to secure the catalyst within the reactor
to give a resilient mounting which compensates for the dif-
ferential expansion of the ceramic/metal interface
e. A stainless steel reactor constructed by conventional muffler
techniques in liaison with a UK exhaust system manufacturer
The ceramic core and container can be constructed in either cylindrical or
oval cross section. The latest catalytic converter (AEC 3A), which is being
evaluated on the Johns on-Matthey 1975 Concept Vehicle (see Section 5. 7. 6).
is oval. Although Johns on-Matthey does not propose to supply such containers
commercially, container designs and resultant characteristics are a part of
the state-of-the-art technology.
5.4.2.6 Universal Oil Products
Universal Oil Products has developed a small cylindrical container for its
pellet catalysts, the combination of which (container plus noble metal/pellets)
is called the Mini-Verter (Ref. 5-9). It is similar to the Engelhard PTX
container in shape; no design details are available.
5.4.2.7 Miscellaneous
As noted in Section 5.4.2.4, both Arvin Industries and the Walker Manu-
facturing Company have been and will continue working with the Ford Motor
Company on catalytic converter development, primarily in canister or
5-35
-------
catalyst containment. Presumably these companies and others also cooperate
with other automotive or catalyst companies and are a potential supplier of
converter canisters.
5.5 CONTAMINATION AND DETERIORATION EFFECTS
A basic problem with catalysts, to date, is their unacceptable deterioration
of conversion efficiency with mileage accumulation. This deterioration results
from a variety of sources, including contamination effects and thermal and
mechanical deterioration factors. The following sections summarize and
discuss the more important considerations as disclosed by recent testimony
and data submitted in support of the EPA Suspension Hearings.
5.5. 1 Contamination Effects
5. 5. 1. 1 Fuel Additives
There is universal agreement that the catalytic efficiency of current auto-
motive catalysts can be lost or reduced by reaction with or blanketing by lead,
phosphorus, and sulfur in gasoline. However there is a scarcity of actual
test data to establish the actual poisoning mechanism and the particular amount
of efficiency degradation attributable to a given contaminat level.
5. 5. 1. 1. 1 Lead Additives
With regard to lead additives, the early recognition of the deleterious effects
on catalyst efficiency with accumulated mileage or test time (as reported in
the recent Aerospace Corporation Lead Cost-Benefit Study, Ref. 5-20) resulted
in the automobile companies conducting more recent catalytic converter
evaluations with either lead sterile gasoline (less than 0.0002 gm/gal) or
gasoline containing relatively low levels of lead (approx. 0.02 to 0.03 gm/gal).
In response to this recognition and additional evidence concerning the deleteri-
ous effects of phosphorus, the Administrator of EPA has promulgated pro-
posed rules (Ref. 5-21) to limit the lead content of gasoline to a maximum of
0. 05 gm/gal and the phosphorus content to a maximum of 0. 01 gm/gal; the
maximum content of sulfur may be regulated upon submission of supporting
evidence to establish the required level.
5-36
-------
The actual lead levels used by the various companies differs widely, as
shown in the following listing of test fuel lead levels.
a. AMC -- <.024 gm/gal (Ref. 5-22)
b. British Leyland -- 0.014 gm/gal (0.02 gr/gal in one
occasion) (Ref. 5-23)
c. Chrysler -- 0.02 - 0.03 gm/gal (all tests to date) (Ref. 5-24)
d. Engelhard -- lead sterile (0.0002 gm/gal) and Amoco Prem-
ium (0.02 - 0.03 gm/gal) (Refs. 5-24 and 5-25)
e. Ford -- primarily 0.03 gm/gal (Ref. 5-19)
f. GM -- primarily 0.02 gm/gal (Ref. 5-16)
g. Matthey Bishop -- <0.0006 gm/gal (Ref. 5-13)
h. Saab-Scania -- 20 ppb (Ref. 5-26)
. i. Toyota -- 0.01 -0.02 gm/gal (Ref. 5-27)
j. Volvo -- 0.015 gm/gal (recent vehicle tests) 5 ppm (some
test fuels) 15 ppm (some bench tests) (Ref. 5-28)
k. VW -- 5-10 ppm (Ref. 5-29)
General Motors stated (Ref. 5-16) that tests were also made with gasoline
containing 0.01 gm gal of lead, but GM could not notice much difference
between these tests and those made with 0.02 gm/gal. Matthey Bishop
(Ref. 5-30) reports that in a 100-hour static engine test run with 0.05 gm/gal
there was only a very slight difference between "zero lead" (<0. 0006 gm/gal)
and 0. 05 gm/gal. Chrysler (Ref. 5-24) believes that catalyst activity degrada-
tion with mileage varies directly with lead content at the lower levels (in the
range of 0.05 gm/gal). Nissan (Ref. 5-31), in consonance with the Chrysler
opinion above, feels that 0.01 gm/gal is preferable to 0.02 gm/gal.
It is evident, therefore, that the specific relationship between catalyst
efficiency degradation and lead level is an elusive one. This is well
illustrated by the Ford data of Figure 5-7, showing durability tests
of an Engelhard PTX converter with ashless oil. As can be noted, although
5-37
-------
I
CO
00
O
oc
80
-O £_
60
40
20
PTX3 0.2% PI
DATE COMPLETED 3-28-72
EVALUATION CONDITION
INL. CAT. TEMP. 800° F
ENGINE SPEED 1000 rpm
WITHOUT AIR
V
FUEL:
Pb FREE
0.035 gm/gal Pb
0.07 gm/gal Pb
OIL: ASHLESS
DURABILITY CYCLE
MODE TEMP. TIME
1000° F
1200° F
1250° F
1200° F
1
2
3
4
14 min
15 min
6 min
7 min
1
200 400
TIME ON TEST, hr
600
Figure 5-7. Effect of Lead Additive on Catalyst Efficiency
-------
definite trends between the lead-free, 0.035 gm/gal, and 0.07 gm/gal levels
can be established, variability in the data would make comparisons between
discrete levels; e.g., between 0.01 gm/gal and 0.03 gm/gal; exceedingly
difficult. Also, since these data were based on engine dynamometer tests
run on nonrepresentive cycles, the relationships may not hold when mileage
is accumulated on systems subjected to representative driving cycles. The con-
clusion that the lesser the amount of lead the better (within practical limits,
of course) is an obvious one. Ford points out (Figure 5-7) that the catalyst HC
efficiency decreases from 90 percent for the lead free case to 80 percent for
lead levels as low as 0. 03 gm/gal, and that this doubled the HC emissions for
the Engelhard catalyst tested (Ref. 5-19).
While there may be some doubt as to whether the effect of lead is a "reactive"
one or one of "mere coating" of the catalyst surface and pores, UOP has pre-
sented test evidence (Ref. 5-32) to illustrate that catalysts have a tolerance
to occasional doses of lead (i.e., have a regenerative property). This is
shown in Figure 5-8, showing lead effects on emissions for a car operated
alternately on "lead-free" and leaded gasoline. Dxiring the early stages of the
test, fuel was alternated between lead-free fuel with about 0.03 gm/gal and
fuel containing 2.5 gm/gal lead. Catalyst recovery when operated on lead-
free fuel is shown for both HC and CO emissions. At about 19,000 miles,
the EPA's proposed regulation on fuels (Ref. 5-21) was published and the
vehicle was switched to fuel containing 0.05 gm/gal lead and 0.01 gm/gal
phosphorus. Catalyst activity, as indicated by the emission levels of HC and
CO remained relatively constant over the balance of the 25,000-mile run.
Universal Oil Products ascribes this regenerative phenomenon to the opinion
that the deleterious effect of lead is one of surface-covering and pore-clogging,
not an irreversible chemical reaction. Further, UOP hypothesizes that
there is an equilibrium-solution relationship between the engine exhaust gas
and lead. With normal concentrations of lead (e.g. 2-3 gm/gal) the amount
of lead is in excess of the amount the exhaust gas can accommodate (at the
catalyst surface and gas temperatures existing in the converter) and therefore
5-39
-------
171
I
CO
00
O
I
CO
in
r*»
O)
E
fcfl
E
bO
1.8 gm/gal
'0.043 gm/gal
'0.01 gm/gal
0. 023 WT
0.01-0.03 gm/gal
0.01 gm/gal
0.01 WT %
0. 04 WT %
__10 15
VEHICLE TEST MILES, in thousands
Figure 5-8. Lead Effects on Emissions During UOP 25,000-Mile Test
-------
the lead deposits continuously out on the catalyst surface, thereby reducing its
active surface area. Conversely, when the engine exhaust gas contains very
low amounts of lead (e.g., approximately 0.03 gm/gal), the exhaust gas can
accommodate more lead in solution and actually picks up lead volatized from
the catalyst surface if it has been previously exposed to higher fuel lead
concentrations.
Notice that this 25, 000-mile UOP test was conducted on a noble metal/pelleted
catalyst which may have operated at temperature levels somewhat higher than
anticipated or used by the automobile manufacturers in some of their tests.
It would be expected that the regenerative phenomenon disclosed by UOP data
is temperature dependent; i.e. , the higher the temperature the lower the lead
deposition rate (with leaded fuels) and/or the higher the lead vaporization
rate from catalyst surfaces.
Therefore, engine systems designed to minimize "raw" exhaust emissions
entering the catalytic converter (lower HC and CO, lower inlet gas tempera-
tures) would appear to be more adversely affected by lead concentrations in
the fuel than engine systems designed to rely on the catalytic converter for
more HC and CO oxidation (higher HC and CO levels to converter).
With regard to pellets versus monolithics, Oxy-Catalyst (Ref. 5-7) indicates
its experience reveals that pellets are more resistant to lead (and other
contaminants) than monolithics. Oxy-Catalyst OC-100 purifiers (using
platinum pellet catalysts) operate effectively for at least 300 hr on regular
leaded gasoline while its monolithic or honeycomb type of purifier is rendered
quite ineffective after only 25 to 50 hours of operation on the same gasoline.
5. 5. 1. 1.2 Phosphorus and Sulfur Additives
Much less specific information is available concerning the deleterious effects
of phosphorus and sulfur on catalytic activity. Saab-Scania (Ref. 5-33) reports
"catalyst poisoning" with fuel containing only 4 ppm phosphorus. The fuel
used in this test had only 20 ppb of lead.
5-41
-------
General Motors tests (Ref. 5-16) have been conducted with 0.02 gm/gal Pb,
0.005 gm/gal phosphorus and 0.03 percent sulfur. It has seen no "significant"
differences in the effects of these contaminants on base metal catalysts as
opposed to noble metal catalysts. General Motors feels that lead may be
worse for base metals, but it cannot prove it. General Motors states
(Ref. 5-34) that if a vehicle is driven with a catalytic converter at tempera-
tures of 900-1200 F (where GM's operates most of the time) this is a temp-
erature range where sulfur readily deposits on the catalyst surface. If the
converter could be designed to operate above 1300 F all the time, then sulfur
problems would be alleviated. General Motors feels that phosphorus effects
are bad regardless of the converter operating temperature (inferring an
irreversible reactive poisoning effect).
Oxy-Catalyst (Ref. 5-7) has provided GM bench test data of their baae metal/
pellet catalyst material HN-1429-1. These data on conversion temperature
and contaminant buildup vs engine running times are shown in Figures 5-9,
5-10, 5-11, 5-12, 5-13, and 5-14, and illustrate the effects of varying contents
of lead, phosphorous and sulfur in the test fuel. While interactions are pos-
sibly involved, the data indicate that sulfur buildup on the catalyst appears
to be especially damaging to carbon monoxide reactivity. This effect is des-
cribed in the figures as the increase in the 50-percent conversion tempera-
ture, or "light-off" temperature, with endurance or running time. Increase
in "light-off" temperature causes increase in emissions when tested under
cold start conditions. These figures also indicate the build-up of lead on the
catalyst with increasing lead content, as discussed above in Section 5. 5. 1.1.1.
No clear phosphorus effects are noted on the figures for the concentrations
tested.
5. 5. 1.2 Oil Additives and Miscellaneous Effects
A recent chemical analysis by Ford (Ref. 5-35) of a catalyst which had been
durability tested revealed contamination from the following sources: lead and
phosphorus from fuel and lubricants; zinc from lubricants; copper from an
unknown source; and nickel, chromium, iron and manganese from the reactor
5-42
-------
£ 900
4*
S
TEST CU MS MATERIAL HN-142t-l
> 2lj) COKVEKTK J» ENGINE - 1
|| FUEL. Pk<.009. P.121. S.05
i L_J 1^
S *°°
z'
100 190 200 290
[CUE lummc TIM. ii
TEST CM-955 MATERIAL HN-MM-1
CONVEHTEII-3SI ENGINE - 2
FUEL. Pb<. 005. P.07, S.
I J __l I
100 ISO 200
EICIII IUNHIK6 TIME, kr
S no
TEST CU-555 M»Tt»l»L m-1429-1
COHVE»TE«-353 ENGINE - 3
FUEL. Pb.5, P<.m, S.04«n/l>l
Figures 5-9, 5-10, 5-11. Oxy-Catalyst Fuel Effects Data
5-43
-------
s rao
i
»
s
5 soo
COMVERTEH-944 ENGINE - 4
FUEL. Pb.OI. P<.005. S.02gm/gol~
i
s
S MO
if
S
2 500
TEST CU-SS3 MATERIAL HN-1429-1
CONVERTER-IS* ENGINE - 5
FUEL. Pb.0». P<.0«. S.04cWcil
100 1U 200
HtlK IUMIM TIME, hi
50 100 150 MO
EKGIIE lUKIIIS TIIK. kr
X
s-
I
« TOO
M
m
I
0 600
*»
m
S soo
-«o.«KH
TEST CM-S5S MATERIAL HN-I4W-1
0.2 |f-/ CONVERTER-352 ENGINE - 6
/ FUEL. Pt><.oos, P<.OOS, S.M \
300' 0
100 in 200
U6I»[ RUKIIK TIKE, hi
Figures 5-12, 5-13, 5-14. Oxy-Catalyst Fuel Effects Data
5-44
-------
manifold liner. Ford feels that further work must be done on reducing
contaminant levels in fuels and lubricants. The metal contaminants are of
particular concern since they could have a serious bearing on the suitability
of a reactor/catalyst combination.
Engelhard has reported a 50,000-mile durability test for their PTX catalyst
(Ref. 5-36). The test was conducted with an unleaded gasoline having a lead
content of approximately 0.03 gm/gal. The catalyst picked up substantial
quantities of Pb, Zn, P, and Ba during the test. The Zn and Ba are con-
taminants that Engelhard associates with motor oil. Engelhard's present
position is that the most probable cause of PTX catalyst deterioration are
metal poisons that may be present in the fuel and lubricating oils.
Matthey Bishop expressed the opinion (Ref. 5-30) that the HC efficiency
deterioration of their catalyst was due to phosphorus pickup from the engine
oil.
5.5.2 Deterioration Effects
5.5.2.1 Thermal Effects
5.5.2.1.1 Alumina Phase Changes
Automotive catalyst pellet substrates are composed of activated alumina
material, as noted in Section 5.2.2. Monolithic substrates also have a
wash-coat of alumina (or promoted alumina) on the honeycomb ceramic
substrate to provide the porosity and high surface area to volume charac-
teristics essential for high catalytic activity.
Although the alumina (pellet or monolith wash coat) does not melt until a
temperature of approximately 3600 F is reached, it does undergo a phase
change from gamma alumina to alpha alumina at approximately 1750°F.
Chrysler states that the effect is one of crystal agglomeration which reduces
the porosity of the alumina to a point where the catalyst reactivity is
significantly reduced. Chrysler states that such an overtemperature exposure
5-45
-------
of only from 1 to 2 seconds is sufficient to result in significant catalyst
deactivation (Ref. 5-24).
5.5.2.1.2 Thermal Shrinkage
Pellet substrates (alumina) are also subject to shrinkage in physical volume
with increased temperature. The effect of such thermal shrinkage is to
reduce the catalyst efficiency via reduced surface area and to cause a
"loosening" of the pellets in the converter canister (in the absence of mech-
anical design features which compensate for the volume loss).
General Motors reported that in early designs excessive shrinkage occurred
at a temperature of 1400 F. It feels that current pellets exhibit satisfactory
thermal shrinkage properties at temperatures up to 1800 F. General Motors
current pellet specifications allow 10-percent shrinkage when exposed to
1800°F for 24 hours (Ref. 5-34).
5.5.2. 1.3 Thermal Differential Expansion
Both pellet and monolithic substrates have thermal expansion coefficients
different from the converter canisters housing them. Upon bed warm-up,
the pellets can become looser in the bed than originally packed. Monolith
catalyst elements also can become "loosened" with respect to the container.
Both may then be subject to mechanical attrition effects as discussed in
Section 5.5.2.2.
5.5.2.1.4 Melting
Although the alumina material (pellet and wash coat of monolith) does not
melt until about 3600 F, the cordierite material used for monolithic sub-
strates (e.g. American Lava ThermaComb and Corning W-l) has a melting
point of approximately 2500-2600 F. Even though the overall bed temperature
is below this level, local zones have been subject to overtemperature
conditions and have melted. Engelhard reports (Ref. 5-18) that this is a self-
limiting phenomenon in that it is local in nature and does not affect the overall
monolith or the canister metal. Toyota (Ref. 5-37) also refers to monolith
melting damage due to local overtemperatures. American Lava (Ref. 5-38)
5-46
-------
confirms the partial internal melting characteristic which reduces the overall
catalyst efficiency but does not necessarily "fail" the entire unit.
A related problem with regard to pellet catalysts is referred to by UOP
(Ref. 5-39). There have been instances wherein pellet catalyst have been
exposed to overtemperature conditions to the point where the pellet retaining
outlet screen burned out (screen melts at 2600°F). The result was that the
catalyst pellets blew out the tailpipe; however, they were cool enough to
handle by the time they left the tailpipe. Also, Nissan (Ref. 5-31) refers to
a test in which a pellet catalyst (of Japanese manufacture) "burned and
stacked together (fused)" under conditions of full-load at 60 mph.
5.5.2.2 Vibration Effects
The catalytic converter is subjected to vibratory inputs from a number of
sources, including road shocks, induced mechanical loads from mounting to
the engine exhaust system (exhaust manifold and/or pipe extending therefrom),
and gas dynamic loads from the pulsating exhaust gas flow.
With regard to induced mechanical loads there is some evidence that second-
order rotational vibrations associated with 4-cylinder in-line engines may be
more severe than 6-cylinder or V-8 engines.
5.5.2.2.1 Pellet Catalysts
In pellet catalysts the principal effects of excessive vibratory forces are
pellet breakup or "attrition". Volvo (Ref. 5-40) reports that in a test run
in March 1972 with an AC-Delco converter the pellets broke up and resulted
in an empty container in approximately 5000 miles. Volvo had similar pellet
breakup with UOP noble metal catalysts. Toyota and Mercedes-Benz
(Daimler) (Ref. 5-41) report similar pellet rupture experience. Chemico
(Ref. 5-3) indicates that pellet attrition requires refill or topping off in
approximately 3000-mile intervals for their current design to maintain 1975
emission levels. They project refill intervals of approximately 8000 miles
for an advanced design.
5-47
-------
On the other hand, GM (Ref. 5-16) states that it currently has no physical
durability problems with their pellet catalysts. It acknowledges pellet
attrition problems prior to early 1970, but claims its converter design has
solved the problem.
5.5.2.2.2 Monolith Catalysts
Nearly all monolith catalysts tested to date have utilized American Lava
substrates of either the spiral (rolled) or stacked (parallel-layered structure)
types as shown in Figure 5-2. Originally, stacked type designs were utilized;
then the spiral type was used. Current monoliths with American Lava sub-
strate are of the stacked type because of severe mechanical cracking problems
with the spiral type. Monolithic catalysts were originally cylindrical in cross-
section; however, oval shapes are also being evaluated.
Volvo (Ref. 5-42) reports a number of monolith mechanical failures, espe-
cially in conjunction with 4-cylinder engine operation. This failure mode is
attributed to characteristically high second-order rotational vibratory
forces. Three Johnson-Matthey oval converters have failed mechanically in
low-mileage tests at Volvo. One of these broke in pieces at 700-800 miles.
Volvo's longest durability test to date (with an Engelhard PTX unit) was
recently ended at 29,900 miles with a failure of the substrate. The substrate
was extruded out of the converter housing; there was no indication of
overheating (Ref. 5-28).
VW (Ref. 5-29) feels that the principal cause of mechanical failure of spiral
and stacked monolithic substrates is the differential thermal expansion bet-ween
the substrate and the container housing which then allows the vibrating move-
ments between the ceramic core and the housing. Saab-Scania (Ref. 5-26)
concurs in this regard. American Lava (Ref. 5-38) feels that the spiral type
of substrate is more susceptible to this type of damage; this is why it has
reverted to the stacked substrate design.
5-48
-------
In an early converter design in which two [end-to-end] ceramic pieces were
used to comprise the catalyst core, Johnson Matthey reports that movement
between the two pieces resulted in mechanical failure (Ref. 5-30).
Chrysler (Ref. 5-17), GM (Ref. 5-16), and Daimler-Benz (Ref. 5-41) also
report mechanical failure problems with monolithic substrates.
Engelhard (Ref. 5-18) claims to have solved the monolithic differential thermal
expansion problem with a patented proprietary design (including wire mesh
between ceramic and container). Matthey Bishop (Ref. 5-13) claims the
problem is solvable by use of improved support materials, insulation between
the ceramic and the canister, and crimped wires between ceramic and the
canister.
5.6 PRINCIPAL PROBLEM AREAS AND PLANS FOR RESOLUTION
Based on the information discussed in Section 5. 5, it would appear that the
primary problem areas associated with the use of oxidation catalysts include
catalyst contamination, inadequate catalyst activity, thermal deterioration,
and catalyst attrition.
The following sections discuss each of these basic problem areas and indicate
the plans underway or proposed for resolving them. Notice that the automo-
tive catalytic converter technology is rapidly changing as a result of intensive
product design, test, and evaluation programs in both the catalyst supplier and
automotive industries. Therefore, the activity and durability data reported by
various companies as their latest results are based often on catalyst mate-
rials and substrates which may be in fact old technology previously discarded
by others. Due to the time-lag inherent in the relationship between the
substrate-catalyst-converter suppliers and the auto makers themselves, it is
natural that some instances reported as "severe problems" by one company
are treated as "solved problems" by others.
5-49
-------
5. 6. 1 Contamination Control
As mentioned in Section 5. 5.1.1, the Administrator of EPA has proposed
(Ref. 5-21) to limit the lead content of gasoline to 0. 05 gm/gal and the phos-
phorus content of gasoline to 0.01 gm/gal for the unleaded grade of gasoline
to be made available for automobiles utilizing catalytic converters. A similar
regulation of the sulfur content in such unleaded grade will also be promul-
gated if the auto companies can present substantive evidence to establish the
needed level.
All parties agree that zero levels of contaminants would be desirable, but
practical considerations such as lead contamination in shipment, and the need
for phosphorus additives used in detergent or carburetor cleaning solutions,
dictate that trace levels of these contaminants will have to be "tolerated" by
the catalysts, at least in the immediate future.
The exact contribution of lubricating oil constituents to catalyst deactivation
is not evident. Ashless oils would certainly help to assure minimization of
this contaminant but such oils have not been widely evaluated and could
adversely affect other engine parts. At present there is no clear picture of
whether or not to regulate lubricating oil composition. Therefore it would
appear that near-term automotive catalysts would have to "tolerate"
conventional lubricating oils.
5. 6. 2 Increased Catalyst Activity
An obvious approach to improving the ability of emission control systems
with oxidation catalysts to meet the 1975 standards is to increase the catalyst
activity. This is particularly true with regard to lowering the light-off
temperature, inasmuch as the sooner after startup that the catalyst is active
the lower the cold start emissions. It would be expected that all catalyst
suppliers would be actively pursuing such technological advancements to gain
a competitive advantage.
5-50
-------
For example, in this area Engelhard (Ref. 5-4) has recently related progress
in improving the catalytic activity and thermal stability of PTX-type mono-
lithic catalysts. Overall progress is demonstrated in Figure 5-15 where all
catalysts shown were thermally aged and evaluated in a bench scale adiabatic
catalyst screening unit. Comparison of data for standard versus improved
PTX show the improved PTX catalyst has greatly increased retention of '
activity for CO and olefinic hydrocarbon oxidation even after, severe thermal
aging.
Johnson-Matthey (Ref. 5-13), another proponent of noble metalAnonolith catalysts,
also has reported similar progress in improved catalytic activity and high
temperature thermal stability. For example, Figure 5-16 illustrates the
low light-off temperature characteristics of its most advanced catalyst,
AEC 3A, and compares it to some of their other noble metal/monoliths and a
base metal (copper chromite) catalyst. The effects of thermal aging on the
AEC 3A catalyst are shown in Figure,5-17. As can be noted, the effects are
similar to the "improved PTX" characteristics of Figure 5-15 in terms of the
50-percent conversion temperature. The figure'shows that exposure to
elevated temperatures increases the catalyst light-off temperature. After
aging at 970 C (1778 F) the 50-percent conversion (or light-off) temperature
is approximately 275 C which compares to a 50-percent conversion tempera-
ture of approximately 280 C for the Engelhard improved PTX cataly.st when
exposed to the same aging temperature (Figure 5-15).
General Motors, currently a base metal/pellet proponent, confirms the basic
difference in activity characteristics between base and noble metal catalysts.
However, GM (Ref. 5-34) points out that the base metal catalyst starts conver-
sion at very low temperatures and the level of conversion gradually increases as
temperature increases. This is shown in Figure 5-18. On the other hand,
the noble metal catalyst does little conversion until a threshold temperature
is reached. The conversion characteristic of the base metal at lower tem-
peratures can be an advantage if the application results in temperatures in
the lower range.
5-51
-------
450
CM
O
400
I S
I %
I S
350
C9
I 300
CO
o
CO
ce.
o
250
CO
200
ID
150
_L
T
95% CONFIDENCE
LIMITS (±2
-------
i
Ul
OJ
100
C/5
50
A EC 3 A
(most
advanced
catalyst)
150
A EC 8 A
CO
HC
I
200 250
INLET TEMPERATURE, C
300
Figure 5-16. Johnson Mathey Catalyst Light-Off Temperatures
-------
100
50
0
200
! I
INITIAL TEST
650-750° C
840-970° C
- 1100° C
300
INLET TEMPERATURE, C
400
STATIC ENGINE DURABILITY TEST:
EFFECT OF TEMPERATURE OVER
A 24-hr TEST ON AEC 3A
Figure 5-17. Effects of Thermal Aging on AEC3A Catalyst
5-54
-------
Ui
A HC
O CO
NOBLE METAL
BASE METAL
300
400
500
TEMPERATURE, °F
600
700
Figure 5-18. Conversion Characteristics of Base Metal and Noble Metal Catalysts
(Standard Bench Test Evaluation)
-------
General Motors also presented data to show how prolonged exposure to
elevated temperature affects catalyst activity toward hydrocarbons and CO.
Figure 5-19 shows how a typical noble metal catalyst deteriorates when
subjected to temperatures in the range of 1200 to 2000 F.
Figure 5-20 shows similar data for a typical base metal catalyst. In the
temperature range between 1200 and 1500 F, there is no significant increase
in the 50-percent conversion temperature and so there is no significant
deterioration in catalyst activity if this temperature range is not exceeded.
(general Motors concludes that these characteristic differences can be
optimized for either catalyst type. In GM's system application, considering
cold start engine operation and catalyst operation at lower temperatures,
these differences tend to be optimized in favor of the base metal catalyst.
With a different physical application of the catalyst, the advantages of the
noble metal catalyst could be optimized.
5.6.3 Thermal Control
Thermal control devices or techniques are required to protect the catalyst
and provide for vehicle safety. The catalyst protection is required to prevent
thermal-associated activity degradation and durability degradation. The
vehicle safety requirement involves protection against overheating problems
which might result in vehicle fires or external fires caused by contact with
hot catalytic converter surfaces. Most devices or techniques -which protect
the catalyst also provide for vehicle safety. However, some vehicle safety
provisions (e.g., heat shields between converter and body floor) do not aid in
catalyst protection. Thermal control devices or techniques are separately
discussed in Section 5.8.
5.6.4 Attrition Control
Advances in both catalyst substrate properties and canister design features
are required to meet the durability requirements of the 1975 emission
standards.
5-56
-------
900
SCO
700
v> 600
500
A HC
O CO
I
I
I
I
1200 1300 1400 1500 1600 1700 1800
24 HOUR SOAK-FURNACE TEMPERATURE, °F
Temperature at which 50% of HC or CO is converted
1900 2000
Figure 5-19. Soak Temperature Effects on Catalyst Activity
(Noble Metal Catalyst)
900
1200 1300 1400 1500 1600 1700 1800
24 HOUR SOAK-FURNACE TEMPERATURE, °F
. 'Temperature at which 50% of HC or CO If converted
1900 2000
Figure 5-20. Soak Temperature Effects on Catalyst Activity
. (Base Metal Catalyst
5-57
-------
5^6.4. 1 Substrate Properties Improvement
Early pellet substrates were subject to severe breaking-up or attrition
a^s well as thermal shrinkage problems. As evidenced by GM's (Ref. 5-34)
cfurrent specification requirements (10-percent shrinkage for 24 hours at
1800°F) and American Cyanamid's statement (Ref. 5-43) that they have
"whipped" the 1800°F and attrition problem, substantial improvements in
p:ellet attrition durability characteristics have already been achieved.
further improvements may be possible.
t
Similarly, the improved catalyst properties described by Engelhard
(Section 5.6. 2) leading to increased high-temperature activity, may result
in improved durability of the alumina wash coat of the monolith catalyst.
5.6.4.2 Canister Design Features
The wide spectrum of catalytic converter mechanical failure types and modes
shown in Section 5. 5. 2. 2 illustrate clearly that the canister (or container)
design must protect the ceramic substrates (pellet or monolith) from exces-
sive vibratory loads and stresses. In view of the inherent fragility of
ceramics, such failures can be ascribed to deficiencies in the canister
support design.
5> 6. 4. 2. 1 Pellet Converters
Aside from GM (AC-Delco) and UOP (Mini-Verter), most companies had
exceedingly poor results with pellet converters. For example, Chemico
(Ref. 5-3) requires pellet addition (due to attrition) at 3000- to 8000-mile
' J.
intervals.
£
t '
General Motors (Ref. 5-16) claims that its horizontal-bed converter design,
in combination with thermal shrinkage improvements in the pellet substrate,
has solved the attrition problem. If so, its internal pellet support arrange-
ment (top and bottom retaining screens, etc. ) is such as to accommodate
5-58
-------
relative thermal expansions of pellets, retainers, and canister shell while
holding the pellets in sufficiently close-packed proximity to prevent vibratory
movement of the pellets against each other.
5. 6. 4. 2. 2 Monolith Converters
Early monolith converters apparently were little more than a sheet-metal
canister housing the ceramic core. In such an arrangement it would be
expected that differential thermal expansion and vibratory loads would severely
damage the catalyst, as has been evidenced.
A number of promising design approaches, however, have been advanced for
solving these problems. For example:
a. Engelhard has a potential proprietary method of
compensating for the differential thermal expansion
between the ceramic core and the stainless steel canister
(wire mesh between them). It also has provided a pin
(extending through canister and wire mesh) to prevent
axial movement between core and canister. (Ref. 5-18).
b. Volkswagen has proposed a spring-loaded sleeve between
the core and canister. (Ref. 5-44).
c. Volvo has proposed the use of rubber mounts for the
converter. (Ref. 5-42)^
d. Johnson-Matthey (Ref. 5-13) claims the problem is
solvable by use of improved support materials, insulation
between ceramic and the canister, and crimped wires
between the ceramic and the canister.
5. 7 EMISSIONS
The following sections summarize pertinent results as to the emission
characteristics of the various catalysts proposed for use. No attempt is
made to summarize all of the existing data; rather, the approach used is to
select those data considered most representative of the current state of the
art of automotive oxidation catalyst technology.
5-59
-------
5. 7. 1 Air Products and Chemicals (Houdry Division)
Houdry has submitted base metal/ pellet catalysts to General Motors,
Chrysler, and other automotive companies. Houdry does not perform vehicle
emission tests and therefore relies on auto company data, (Ref. 5-1).
5. 7. 1. 1 Low Mileage Emissions
Tables 5-6 and 5-7 indicate the properties of four catalysts supplied to GM
(Ref. 5-1) and two catalysts supplied to Chrysler (Ref. 5-1) together with low
mileage emission data as provided by the auto companies to Houdry. Notice
that all six catalysts were well below the 1975 HC standard, but two catalysts
exceeded the CO standard, even at low mileage.
5. 7. 1. 2 High Mileage Emissions
An early Houdry catalyst was evaluated in a 50, 000-mile durability test by
AC but demonstrated declining performance (Ref. 5-1). The results of this
evaluation are shown in Figure 5-21. It was discovered at the conclusion of
the test that 40 percent of the volume of the catalyst and 20 percent of the
initial weight had been lost, indicating substantial shrinkage and attrition.
It was not until the fall of 1971 that catalysts with sufficient physical strength
has been prepared by Houdry to justify extensive durability tests by AC. The
results of these later AC durability tests and of Chrysler durability tests are
not yet available to Houdry.
5. 7. 1.3 Comparison with Auto Company Data
Pertinent recent test data from General Motors (Ref. 5-45) and Chrysler
(Ref. 5-17) are shown in Table 5-8. Notice that no tests at extended mileage
meet the 1975 standards.
5-60
-------
Table 5-6. Emission Data From Air Products and
Chemicals Corp. (Houdry)a
Catalyst A B '
50% conversion
fresh condition
CO (°F)
HC (°F)
50% conversion
1800°F-24 hr. aging
CO (°F)
HC <°F)
Shrinkage after 1800°F
24 hr. aging, vol. %
Attrition after 1800°F
24 hr. aging, wt. % loss
402 390
442 423
407 443
664 598
18.4 5.0
8. 7 2. 7
C D
402 421
418 424
470 438
565 ' 467
3.2 .2.0
2.3 1.5
Car Test Results (AC)
1975 CVS-CH Emissions
HC, gm/mi
CO, gm/mi
aCatalysts supplied to AC
0.27 0.32
3.3 3.2
Div. of GM (Ref. 5-1)
0.28 0.30
3.3 3.8
5-61
-------
Table 5-7. Emission Data From Air Products and
Chemicals Corp. (Houdry)a
Catalyst E ,_, F
50% conversion
fresh condition
CO (°F)
HC (°F)
50% conversion
1800°F-24 hr. aging
CO (°F)
HC (°F)
Attrition after 1800°F
24 hr. aging, wt.%loss
Chrysler dynamometer
(Car 259)
gm/mi
1
Catalysts submitted to
b!700°F-16 hr. aging
C1800°F-24 hr. aging
396 390
454 423
355 443
359 598
3. 6b 2. 7C
test
Run No. HC CO HC CO
(73) 0.23 3.6 0.26 3.4
(74) 0.20 2.8
(75) 0.28 4.9
(76) 0.20 3.6
(77) 0.19 3.5
(78) 0. 17 3.6
Avg. 0.21 3.65
Chrysler Corp. (Ref. 5-1)
r
x
5-62
-------
U1
I
OJ
1.8
1.6
1.4
1.2
CO
§ 1.0
oo
0.8
0.6
0.4
0
AC CM714 260 cu in. CONVERTER
INDOLENE CLEAR FUEL
350 CHEVROLET 2 BBL CAR 60328
1970 B WITH AIR
HC DETERIORATION FACTOR = 2.19
10,000
20 E
CO DETERIORATION FACTOR = 1.77
1972 CVS-C TEST PROCEDURE
15
10
E
tao
V)
20,000 30,000
AMA DURABILITY, mi
40,000
O
50,000
Figure 5-21. Durability Data for Houdry Base Metal Catalyst PIN 1269
-------
Table 5-8. APCC (Houdry) Catalysts (Auto Co. Data)
C«r No.
Chrysler
259
CM
62403
62411
62102
62115
61203
61322
61318
62505
2586
Car and/or CIO
360
Oldsmobile 455
Oldsmobile 455
Buick 455
Skylark 455
Cadillac 472
Chevrolet 350
Chevrolet 350
Pontiac 455
Oldimobile 350
Test
Weigh!
5000
5500
5500
4500
5500
4500
4500
4500
5000
Telt
Date
2/72
1/72
2/72
4/72
2/72
2/72
3/72
12/71
4/72
2/72
2/72
4/72
4/72
2/72
J/72
System Description
AI
X
X
X
X
X
X
X
X
X
X
EGR
X
X
X
X
X
X
X
X
X
X
Mod.
Carb.
X
X
X
X
X
X
X
X
X
X
EFE
X
X
X
TR
30%
Siae
Catalyst
Base/Pellet
(1057 JX8-2X1)
Baie/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX4-1X1)
Baie/Pellet
(1259 JX3-1X1I
Base/ Pellet
Base/Pellet
Bate Pellet
(1259 JX3-1X1I
cvs
Teat
Proc.
1972
1975
1975
1975
1975
1975
1975
1975
1975
1975
Test '
Mileage
0
170
118
240
1.689
280
300
0
1, 158
0
21, 178
6
1.465
1.914
3.778
42
1. 168
Emissions, gm/mi
HC
0.23
0. 17
0.45
0.52
0.63
0.70
0.25
0.44
0.66
0.25
0.87
0.22
0.57
0.36
0.5J
0.28
0.71
CO
3.6
3.6
5.4
5.0
3.2
2.5
6.0
3.2
10.3
2.9
4.1
0.9
2.4
1.3
1.75
7.3
12.5
N0x
1.21
1.83
1.0
0.9
1.0
0.9
0.9
0.2"
0.2"
.9
.6
.4
.4
.1
.0
3.7
3.8
Remarks
System Development
System Development
System Development
System Development
System Development
Catafyst changed;
Excessive Deterioration
Test continuing
Discontinued; high
deterioration
Overtemperature
*NO catalyst in system
-------
Table 5-8. (Continued)
Car N'o
2823
18504
2233
2590
2539
2878
2242
62124
62125
62126
62127
ar an /or
Oldsmobile 455
Oldsmobile 455
Oldsmobile 455
Oldsmobile 455
Oldsmobile 455
Oldsmobile 455
Buick 350
Buick 455
Buick 455
Buick 455
Buick 455
Test
Weiizht
5500
5500
4500
5000
5000
5500
4500
5000
5000
5000
5000
Test
ate
1/72
1/72
2/72
3/72
3/72
12/71
1/72
1/72
2/72
3/72
2/72
3/72
2/72
3/72
1/72
1 l~f
_/ i L
3/72
3/72
2/72
2/72
3/72
3/72
2/72
2/72
3/72
3/72
2/72
2/72
3/72
3/72
2/72
2/72
3/72
3/72
System Description
AI
X
X
X
X
X
EGR
x
x
X
Mod.
Carb
X
X
X
X
X
X
X
X
X
X
EFE
TR
Base/Pellet
(12J9 JX3-1X1)
Base/Pellet
(1259 JX3-1X1J
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(12 59 JX3- 1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
11259 JX3-1X1)
Test
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
Test
10
3, 336
8 927
91
487
0
14.227
19.668
24,304
30.037
47
1.418
1
1, 139
0
2 460
0
3,950
43
2,910
7, 280
10, 097
32
3,201
7. 198
10,469
33
3,381
7,096
10,079
17
3, 342
7, 111
10, 006
Emissions gm/mi
HC
0.34
0.41
0 62
0.25
0.26
0.31
0.48
0.52
0.56
0.73
0.42
0.61
0. 30
1.04
0.22
0.51
0.56
0.74
0.38
1.08
0.43
0.98
0.64
0.72
1. 16
1.24
0.54
0.65
0.67
0.71
0. 56'
0.91
0.93
0.99
CO
10.7
10.3
11 6
3.0
1.8
5.6
10.7
11.7
8.6
10.6
7.0
7.9
4.6
11.0
1 c
5.9
5.7
4. 1
7. 2
3.6
9.9
3.6
4.0
7. 1
9.6
2. 1
3.3
3.8
3.2
3.9
9.3
9. 5
10. 1
NO
X
i. 1
2.0
2 n
3. 1
1.4
2. 1
1.6
1.6
1.9
2.3
2.3
3.5
2.3
2.4
3.8
Si
. 0
1.8
1. 5
5.6
5.3
4.9
5.9
5.7
5.7
5.8
5.7
6.0
5.5
4.9
5. 1
5.7
5. 1
5. ;
Remarks
.
Test continuing
Teat discontinued
Over temperature
Over temperature
Test continuing
Changing catalyst
Changing catalyst
Changing catalyst
6. 5 Changing catalyst
(Jl
I
Ul
-------
Table 5-8. (Continued)
Car No.
62129
62128
62130
62115
931
2222
Car and/or C1D
Buick 455
Buick 4SS
Buick 455
Buick 455
Buick 4SS
Cadillac 500
Test
Weight
5000
5000
5000
4500
5000
5500
Test
Date
2/72
3/72
4/72
2/72
2/72
3/72
3/72
2/72
3/72
3/72
1/72
3/72
12/71
1/72
1/72
1/72
2/72
4/72
System Description
AIR
X
X
X
X
X
X
EGR
X
X
X
Mod.
Carb.
X
X
X
X
X
EFE
X
TR
Catalyst
Base/Pellet
(1259 JX1-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(125S JX3-1X1)
Base/Pellet
(1259 JX3-1X1)
Base/Pellet
(1259 JX3- 1X1)
Base/Pellet
(1259 JX3-1X1I
Telt
Proc.
1975
1975
1975
1975
1975
1975
Test
Mileage
48
3,400
7,401
48
2,660
7,079
10, 104
39
3,405
7,362
323
876
0
7,544
0
2,000
4, 000
8,000
Emissions, gm/mi
HC
0.48
0.60
0.80
0.52
0.75
1.08
1.00
0.53
0.65
0.86
0.60
1.25
0.29
0.64
0.35
0.40
0.35
0.32
CO
3.0
3.5
6.7
4.2
6.6
8.8
9.7
4. 1
5.9
7.6
3.0
5.5
2.3
6.7
1.1
2.3
3.2
4.6
NO
X
5.8
5.0
i. 1
6.2
4.5
5.3
5. 1
4.4
4.8
3.7
1.3
1.3
6.0
4.0
2.0
1.9
2. 1
2.6
Remarks
Test continuing
Changing catalyst
Test continuing
Changing catalyst
Test discontinued
Test continuing
-------
Table 5-10. Emissions Data From Chemico for Federal Clean Car Incentive Program
Test
Date
3/7/72
3/8/72
3/9/72
3/10/72
3/16/72
3/25/72
3/27/72
3 / ?Q /7 >
J 1 £-7 f 1 ft
3/30/72
3/31/72
4/6/72
4/7/72
4/11/72
Test Mileage
. Accumulated
1,495
1, 505
1, 517
1, 529
1, 588
1, 677
1, 790
6 595
6,607
2, 019
2, 556
2, 567
2, 784
Vehicle
Tested
(A)
(A)
(A)
(A)
(A)
(A)
(A)
/O V
\°)
(B)
(A)
(A)
(A)
(A)
System Configuration
Mach VIII
Mach VIII
Mach VIII
Mach VIII
Mach VIII
Mach VIII
Mach VIII
Standard production car
Mach VIII
Mach VIII
Mach VIII
Mach VIII
lot Bed
Catalyst
A
A
A
A
A
A
A
None
A
A
A
A
2nd Bed
Catalyst
A
A
A
A
A
A
A
None
A
A
A
A
\1975 CVS-CH
Tent Procedure
NO
HC CO N0x
0.23 3.32 0.33
0.1.5 1.36 0.26
0.29 2.63 0.32
0.19 2.29 0.31
0.18 1.50 0.24
0.19 1.12 0.29
0.28 1.67 0.43
3/V4 An ft ] i Q ?
, \Mt %U. U 1 J , 7 <-
2.35 30.26 2.85
0.38 2.18 '0.30
0.46 1.81 0.30
0.63 2.06 0.36
0.37 1.27 0.32
Fuel
Consumption,
mi/gal
10.6
11.0
9.91
9.95
9.98
12.9
9.48
UQ
. 7
10.9
9.97
9.75
10.40
9.97
Remarks
Meets 1976 standards
Meets 1976 standards
Meett 1976 standards
Meets 1976 standards
Meets 19.76 standards
Meets 1976 standards
Meets 1976 standards
Meet B 1972 stan da rds-
Meeta 1972 standards
Meets 1976 standards
Distributor points burned
Distributor points burned
Points replaced
Meets 1975 standards
Vehicle Tested: (A) 1971 Oldsmobile - Delta 88 - 350 cubic inch displacement - Test Inertia Weight: 4500 Ib
(B) 1972 Oldsmobile - Delta 88 - 350 cubic inch displacement - Test Inertia Weight: 4500 Ib (Avis Rental Car)
Tester/Location: Environmental Protection Agency - Ann Arbor, Michigan
-------
In September 1971, CHEMICO's car was tested at GM Tech Center and again
the emissions were below the 1976 emission levels.
In February 1972, CHEMICO's car was tested at Scott Research Laboratories,
Plumsteadville, Pa. This car was submitted to EPA for evaluation under the
Federal Clean Car Incentive Program. Early results from this EPA evalu-
ation are presented in Table 5-10. All test data shown are for low mileage
(less than 1500 miles) and with fresh catalyst. Considerable catalyst attrition
was evident even below 1000 miles.
5.7.3.2 High Mileage Emissions
CHEMICO has no high mileage emission data.
5.7.4 Engelhard
Engelhard has been very active in performing tests to demonstrate the
applicability of noble metal/monolith catalysts for automotive use.
5.7.4. 1 Low and High Mileage Emissions
5. 7.4. 1. 1 Durability on Dynamometer
As a baseline for durability of standard PTX-433, a test -was run on an engine
dynamometer using the mileage accumulation schedule shown in Figure 5-22
(Ref. 5-4). With this schedule inlet temperatures to PTX purifiers are
approximately 900-1000 F. This particular catalyst was first tested on a car
using lead sterile fuel. The car was involved in an accident at 4156 catalyst
miles. One of the two purifiers on that V8 vehicle was damaged. The purifier
which was intact was removed and installed on an engine dynamometer, and
an additional 31,665 miles were accumulated with lead-free fuel and ashless
lubricating oil. The results are shown in Figure 5-23.
After a total of 35, 821 miles, the emissions were 0. 35 gm/mi for hydro-
carbons and 3. 0 gm/mi for carbon monoxide.
5-70
-------
20
10 -
20 40
60 80 100
TIME IN CYCLE, sec
720 740
Figure 5-22. Englehard Mileage Accumulation Cycle for
Engine Dynamometers
5-71
-------
HC
GRAMS
PER
MILE
2.5"
2f\m
1.5«
1.0*
0.5«
1.9 1975-76 Standard
..
1.6
1
i
i
0.16
Eli!
1
1
i
0
0.13
R2E1
.41
1.2
rrsj
1
i
gro
^
ms per mile
' 0.35
1
j|j(
Baseline 500 Baseline 4,156 Baseline 35,821
0 (3) (3)
MILEAGE
30*
25-
co20'
GRAMS 15i
PER
MILE10'
5*
t
Z5.<
1
1
1
1
^
1
3
1
0.52
1
1
c?S
I
2.4
EHJ
i
IS:
si
^
1
1
1
1
i
vk
1
^
Sr
.
1975-76
3.4 grams per mile
V 3.0
i
SSi
i
Baseline 500 Baseline 4,156 Baseline 35,821
(!) 0) (3)
MILEAGE
O^DYNAMOMETER:
351 C.I.D. VB Engine
Equipped with Air Pump,
NoEGR
NOTES
1
Up to 4,156 miles accumulated
on car (350 C.I.D. V8, air
pump, A.I.R., no EGR) with
lead sterile fuel and ashless
lubricating oil, 500 miles
test on this car.
2. 4,156-35,821 miles accumu-
lated on engine dynamometer
with lead free fuel and
ashless lubricating oil.
3. CMS Test on car
351 C.I.O. VQ, air pump,
Thermactor, no EGR.
4. All data per 1975 CVS-CH
Test Procedure .
Figure 5-23. Engelhard PTX-433 Catalyst Durability Test
5-72
-------
5. 7. 4. 1. 2 Standard PTX Catalyst Durability Data
5. 7. 4. 1. 2. 1 FTP Hot Cycle Emission Data
A 50, 000-mile durability test was conducted (Ref. 5-25) for a standard PTX
catalyst on a Ford Torino station wagon equipped with a 351 C. I. D. V8 engine,
automatic transmission, no air pump, and no EGR. Each bank of the engine
has a PTX-433S catalyst located about 18 inches downstream of the manifold
under the front floor board. Commercially available lead-free fuel and
standard lubricating oil were used. A city-suburban driving cycle was used
for mileage accumulation with an average speed of 28 mph. This cycle con-
sisted of driving on rural, city, and turnpike roads. The FTP hot cycle
emission results for one of the PTX catalysts are shown in Figure 5-24. The
catalyst maintained a high level of activity throughout the test period.
5.7.4.1.2.2 1975 CVS-CH Emission Data
To establish activity durability of the present PTX catalyst using 1975 CVS
test procedures, a 25,000-mile test (Ref. 5-25')f wa-s conducted with a 1975
prototype exhaust emission control system which included an air pump, an
exhaust gas recirculation (EGR) system, and two PTX-5 catalytic converters
on a V-8 engine. A city-suburban driving cycle was used for mileage
accumulation; Engelhard does not have a test track to allow strict compliance
with the EPA Certification Test. Emission tests were conducted at approxi-
mately 4000-mile intervals. The data from this test are presented in
Figure 5-25 in terms of HC and CO concentrations and catalyst system effi-
ciencies. Catalyst deactivation during the 25,000-mile test was minimal for
HC. The CO emissions increased by about 50 percent but were still below
the 1975 standards.
5.7.4. 1. 3 Durability Test by Automotive'Company
Engelhard has a close working relationship with substantially all of the
domestic and foreign automotive companies. Figure 5-26 presents durability
data reported by American Motors to Engelhard (Ref. 5-4). The test car
5-73
-------
a.
O
u
* Con version efficiency
86%
2084
286
74%
2676
^
696
92%
2650
210
96%
2080
1
82%
3590
1
630
96%
3590
97%
1230
1
570
4.852
11.106 16.393
24,657
33,500
36,641
48,300
MILEAGE
5
a.
'Conversion efficiency
96%
217
8
81%
185
82%
236
^
88%
295
1
35
78%
199
43
I
43
I
79%
165
36
79%
165
34
82%
130
23
570 4,852 11,106 16,393 24,657 33,500 36,641 48,300
MILEAGE
Figure 5-24. Engelhard Federal Test Procedure Hot Cycle
Emission Data for a PTX-433-S Catalyst (Ford
Torino - 351 CID Engine)
5-74
-------
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
1975-76 STANDARD
0.41 grams per mile
. 38 - -OJJ 0.37- _ 0.40 _ o. 39 _ _
n n n n n
BASELINE 380 4125 8247 12,54019,53225,26025,268
(1) (1)(2) BASELINE
MILES
35
30
25
20
15
10
30.2
-1975-76 STANDARD
3.4 grams per mile
-2. 1"2. 15i.g- 2.0--2.2--W--
n FI n n n 11
BASELINE 380 4125 8247 12,54019,53225,26025,268
(1) (1)(2) BASELINE
MILES
ON CAR - 351 C.I.D. V8 ENGINE
PTX-5 (8 corr. per in.)
CAR EQUIPPED WITH 1975
PROTOTYPE SYSTEM - EGR,
AIR PUMP, PLATINUM
CATALYST CONVERTER
NOTES:
1. Manifold to catalyst insulated.
Air pump output partially diverted
after cold start.
2. Catalyst annul us insulated to
'prevent bypassing
3. No other adjustments to
engine during test
4. Lead sterile fuel and ashless
' lubricating oil
5. 1975 CVS-CH test procedure used
6. City/suburban driving cycle
BASELINE - CAR WITHOUT CATALYST
level less than 3.0 grams per mile)
Figure 5-25. Englehard PTX-5 Catalyst Durability Test
5-75
-------
(All
* CYLINDER CAR
except » indicated are '72 CVS-C test. '75 emission
are Hated in terms of '72 CVS-C tests.)
CRAMS
MR
Mill
0.70
0.4A
fcJAV
0.40
o.ao
0.10
0.10
9f
m*t-
**«
ri
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AM
7
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A4».A. MILIACI IN THOUSANDS
«*
is.
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CRAMS '
Mi t,
Mill
* ' ' A.
'
:: : " ' >', ;, '
..'* '; :
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W75-7* STANPARD
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:j ':>'"''' "
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,A,M,A, MILIAOI IN THOUSANDS
' 1.S-2-0 gram* per mile)
1975 CV8-CH
Figure 5-26. American Motors Durability Test of Englehard
Catalyst
-------
was new, but was not equipped with the improved chokes and carburetors
projected for use in 1975 cars. The AMA driving cycle was used for mileage
accumulation and, generally, emission tests were made at 4000-mile intervals
using the 1972 CVS-C procedure. At 50, 000-miles, a test was made using the
1975 CVS-CH procedure. As shown in Figure 5-26, the hydrocarbon emissions
were 0.38 gm/mi and carbon monoxide emissions were 6.46 gm/mi.
According to AMC, most of the carbon monoxide was emitted during the cold
start portion of the test and that the projected 1975 choke and carburetor
modifications might be expected to improve the system performance.
5.7.4.1.4 Retrofit Fleet Test of Durability
In addition to working with automotive manufacturers, Engelhard Industries
has cooperated with fleet owners who are interested in retrofitting their cars
or trucks with catalytic devices. One of these has involved the evaluation of
PTX units by the city of New York on Police Department patrol cars
(Ref. 5-4). The cars are 1971, six cylinder vehicles which has been using
commercially available unleaded fuel prior to catalyst installation. However,
since at some time the cars could have been inadvertently filled with leaded
gasoline, the fuel and oil systems were drained and refilled with commer-
cially available unleaded fuel and 10W30 engine oil (1. 2 percent sulfated ash).
The cars are not designed to meet 1975 emission standards and have slowly
acting chokes. In one instance, the choke did not fully open until 200 seconds
after the start of the test. The retrofit consisted of an air pump and a PTX-5
catalyst. Mileage was accumulated in the normal service of police work, and
there have been no unfavorable comments on driveability by the Police
Department.
These tests are still in progress; the most recent data furnished by the city
of New York using the 1972 CVS-C procedure are presented in Figure 5-27.
As shown in this figure, the reduction of hydrocarbons and carbon monoxide
emissions is significant.
5-77
-------
Equipment - 1971 Special Police Model (6 Cylinder) Equipped With
PTX-5 & Air Pump No NOX Control
Fuel: Amoco Unleaded Lube Oil: 10W3O (l.2%Sulfated A»h)
Te«t Precedure..1972 CVS C Procedure (Single Bag) Te»t Every 4,OOO Miles
HC
GRAMS
MIL!
CO
GRAMS
PER
MILE
7.0-
6.0'
5.0-
4.0'
3.0-
2.0'
l.O-
4. 55
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9.S7
POUCI CAI NUMMI 1693 1866 2351 378 476
MILES ON CATALYST 16,469 15,289 10,496 2,294 1,6O8
70.'
60.-
50.'
40.<
3O.<
20.-
10.'
47.5
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1.56
poiici CAR NUMtii 1693 1866 2351 378 476
MILES ON CATALYST 16,469 15,289 10,496 2,294 1,608
BASELINE Eiian^a OUTLET
(Car without catalyst)
Figure 5-27. Emission Data on New York City-Owned Police
Cars Equipped with Engelhard PTX-5 Catalyst
5-78
-------
According to Engelhard, the emission data for cars 1693, 1866, 2351, and
378 indicate a deficiency of required secondary air in some parts of the test
cycle. Engelhard feels that a proper balance of,raw emissions and secondary
air would improve efficiency.
5. 7.4. 1. 5 Activity for Removal of Reactive Hydrocarbons
Engelhard stresses (Ref. 5-25) that although the activity of a catalyst in use
generally decreases with time, the PTX converter retains a high activity for
the conversion of photochemically reactive hydrocarbons--olefins and
aromatics--commonly recognized as being smog precursors. This is
illustrated in Figure 5-28 which compares the activity (at steady state 30 MPH)
of a PTX catalyst after 500 and 50, 000 miles.
According to Engelhard, the significance of this finding is that there need be
no stringent limits on olefin and aromatic content of lead free fuel when the
PTX converter is used for automobile exhaust gas purification.
5. 7.4. 1. 6 Improved PTX-Type Catalyst Durability Data
The data presented in Figures 5-23 through 5-28 were obtained with the
standard PTX designed for automotive use. However, Engelhard (Ref. 5-4)
feels that improvements can be made and expects to accomplish these prior
to the 1975 model year. The improvement potential of Engelhard "second-
generation" catalysts is indicated by its laboratory and engine dynamometer
tests, but general durability confirmation has just started.
Figure 5-29 presents durability data for one of these improved catalysts which
was tested with the air pump output partially diverted after cold start. Lead-
sterile fuel and ashless lubricating oil were used. Prior to the 8550-mile
test, the distributor points were replaced and the,ignition readjusted.
Figure 5-29 shows that the hydrocarbon emissions for the improved PTX-5
at 8550 miles were 0. 26 gm/mi as compared with the standard PTX-5 with
0.41 gm/mi at 8247 miles in Figure 5-25. The carbon monoxide emissions
5-79
-------
00
o
FRESH PTX AGED PTX
(after 500 mi) (after 50,000 mi)
SMOG PRECURSORS
% REMOVAL OF HYDROCARBONS
ACETYLENES 100.0 100.0
OLEFINS
AROMA TICS
99.1
99.1
93.7
93.4
OTHER HYDROCARBONS
OTHER PARAFFINS 93.9 36.8
METHANE 11.3 9.6
TOTAL HYDROCARBONS 97, 1 81.4
(carbon basis)
DECREASE IN TOTAL REACTIVITY 99.2 91.9
OF EMITTED HYDROCARBONS
Figure 5-28. Engelhard Test Results (Steady State 30 MPH) - Removal of
Olefins and Aromatics After 50, 000 Miles
-------
HC
GRAMS
PER
MILE
3.5-
3.0.
2.5,
2.0.
1.5.
1.0.
.5.
ON
1351 C.I. D.
2.4
(
- u:
1 L
1 , "
r
! -1,
J l>
J_
' t -L
CAR
V8 ENGINE)
. Car oquippad with 1975 prototype
syst0m--EGR, air pump and
catalytic converter.
"°'22~ 0.18-
BSSJS1^^ ^WTfMRl
BASELINE 0 513
1975-76 STANDARD
O.41 grams per mil*
0.23 0.26
«M»; IMNTOl '
5350 8550
CO
GRAMS
PER
MILE
30-
25..
20-
15..
10..
5..
26.0
; ..r.
iii'-'iJHS'lii
.r:..;-p
Bill
F" '?.;!
'". !-'--.i:. .:'r^
"..: '*'.
Pii
1975-76 STANDARD
3.4 grams p»r mil*
1
2.10 "2.30
BASELINE O 513 5350
(NOx'*vtl Uss tkoi 3.0 gn« / nil*)
8550
Figure 5-29. Engelhard Imoroved PTX-5 Catalyst Durability Test
5-81
-------
for the improved PTX-5 after 8550 miles were approximately the same as
the standard PTX at 8247 miles (See Figure 5-10).
5. 7. 4. 2 Comparison with Auto Company Test Data
Representative auto company test data for Engelhard catalysts are presented
in Tables 5-11 through 5-17.
5.7.5 W. R. Grace
W. R. Grace uses two 350-cu-in. Chevrolet automobiles in its test work: the
first, a 1970 Impala; the second, a 1971 Chevelle (Ref. 5-5). These are
regular production cars to which they have added an air pump which injects
air into the exhaust manifold.
5. 7. 5. 1 Low Mileage Emissions
Table 5-18 summarizes typical results obtained with Grace oxidation catalysts
in the fresh condition. The circled values represent values at or below 1975
standards. In this tabulation, the catalysts designated as "D-" are materials
which have been supplied to automobile manufacturers for test; those desig-
nated "R-" are still experimental materials. The emission levels of these
cars, when operated with air injection in the manifold and no catalyst, are of
the order of magnitude specified with regard to hydrocarbons and CO by the
State of California for 1974.
As of the present time, Grace feels that two of its catalysts are candidates
for commercial production. These are Davex 142, a base metal pellet
catalyst, and Davex 502, a noble metal monolith catalyst.
Davex 502 was s.elected on the basis of data from Runs No. 221, 300, and 383
in Table 5-18. Notice that Davex 142 (Run No. 487 in Table 5-18) does not
meet the 1975 standard with respect to carbon monoxide. However, it has
been reported to Grace by the A-C Division of General Motors that tests with
the Davex 142 catalysts have resulted in low mileage emission levels of
0. 20-0. 25 gm/mi of hydrocarbons and 2. 0-2. 5 gm/mi of carbon monoxide.
5-82
-------
Table 5-11. Engelhard Catalyst Data- -Chrysl
Test
Xo.
1
21
1
6
30
2
1
35
1
30
1
27
7 '
24
1
20
21
1
1
12
Car Xo.
119
134
145
258
278
303
306
326
333
376
385
Model and/or CID
440
GP57H43/360
318
CD57E41/360
GD57-41/360
CP57H43/360
GP57H43/360
HD63-M-41/400-2V
360
HV24/225
360- 2V
Test
Weight
Test
Date
Sys em Description
AI
EGR
X 1
X
X
x
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Mod.
Garb.
X
EFE
TP
30rc
Size
Cast
Reactors
Cast
Reactors
i
Catalyst
Xoble/Mo-,o
0. 2rj Pt; Oval
Test
Proc.
1972
1975
135 ir,.3 i
Xoble/Mono
0.2~:, Pt;
5 in. o. d.
90 in. 3
Noble. 'Mono
Oval (under seat)
Xoble/Mono
0.35^ Pt.
Noble/Mono
Xoble/Mono
0. 2"i Pt; Oval
Xoble/Mono
0.2r, Pt; Oval
135 in. 3
Xoble/Mono
0. 2T» Pt; Oval
Xoble/Mono
0.2% Pt ; twin
Xoble/Mono
PTX 523
Xoble/Mono
O.SS0"; Pt.
1972
Test
Mileage
Emissions, gm/mi
KC
0 0. 51
1,263
0. 23
0 : 0. 13
1972 133 0.15
1972
1*75
1972
1?75
1972
1975
1.7:2 0.40
0
CO
3.C
l.n
4. 3
3.4
5. 9
1.66
10 0.22
627 0.23
15 0.22
1,446
0. 14
i
1972
1972
1972
1975
1972
1972
1972
1975
1?72
1972
0
1, 294
1.030
1, 201
0
35,943
36,094
0
0
20, COO
0.37-
0. 24
0. 12
0.48
0.41
0.36
0. 33
0. 35
0.28
0.26
15.0
.:O
3. 5
1.28
Remarks
Xo EGR
EGR added; choke
modification
4.41 Xo EGR
2. 25
2. 24
EGR above 120UF
2. 17 Yerv rich choke
!
2.6 1.54
0.9
3.3
1.2
4. 3
8.0
5. 7
2.3
2.48
4.7
4.1
4. :
4.3
:.34
5. 44
2. 3
3. 6;
4.05
1.67
. 54
2.4
1.49
0. 78
1. 56
2. 24
2. 19
1. 56
EGR off
Xo EGR: double wall
exhaust pipe added
Double wall exhaust p;
Baseline with EGR
Replaced mono wraupi
Catalyst failed
5-83
-------
Table 5-11. (Continued)
Test
No.
10
3
1
14
3
4
5
6
1
3
1
5
Car No.
467
499
585
624
650/698
683
Model and /or CID
HP57P43/.360
HP57/360
440
400
400
360
Test
Weight
Test
Date
A!
x
x
!
1 X
'
X
EGP.
x
x
Sys
Mod.
Carb.
om ilJvi s c
ETE
,
r-i'-Xion
TR
Cast
Ke actors
30Tt Cast
Reactors
Catalyst
Noble/ Mono
0. 2T. Pt; Oval
Noble/Mono
0. 1*1 Pt; Oval
Noble/Mono
0. i*i Pt; Oval
Noble /Mono
O.i"'-. Pt; 5 in.
o.d.
Noble/Mono
0.2T» Pt; Two
4 in. diam units
Noble/Mono
0. 2"; Pt; Oval
Test
Pvoc.
1575
197;
1V75
1972 Hot
Hot
7-rr.^de
1°72 hot
1972
1972
Test.
Mileaje
171
107
0
13,676
.0
381
i;l°4
0
43. 000
n
8, 350
ErrisEi&r.s, gm/rr.i
HC CO NOX
0.12 6.5 1.43
0.2 3.3 2ilv
0. 73 2. 3 2.41
0.44 2.1 1,. 50.
0.10 5.9 3.12
0.37 3.2 4.49
0.20 2.8 '4.26
0.12 4.6 3.66
0. 12 1. 51
0. 16 1.88 3.91
0.03 3.8 3.31
0.11 6.74 3.07
Remarks
[ Leaded fuel used
I Unleaded fuel used
Converters damaeed
Double wall exhaust J
EGR above 120°F
5-84
-------
Table 5-12. Engelhard Catalyst Data--Volvo, International
Harvester, American Motors, and General Mot
Test
Xo.
520
776
433
913
1099
601
1091
Car No.
OB 46232
OB 46234
OB 54821
OB 46234
and
OB 44083
161
DOO-24
DOO-25
61319
1420
17934
Car and/or CID
'72 Model 142 E; Engine B20F
Model 144; Engine B20F
Test
Weight
'
Model 144; Engine B20B
'72 Model 144; Engine B20F
1100 D Travelall: V-345
232-6
232-6
Chevrolet 350
Opel 1.9 liter
'71 Buick - 455
3000
3000
4500
2500
Test
Date
12/10/71
2/15/72
11/29/71
3/3/72
4/7/72
1/10/72
4/7/72
1/20/72
2/26/72
3/26/72
8/71
11/71
2/72
2/72
2/72
1 |
System Description
AI
X
X
X
X
X
X
X
X
X
X
ECR
X
X
X
Mod.
Carb.
!
EFE ' 7R Catalyst
Xoble/Mo:io
1 ' PTX-416
i
! ! Xoble/Moao
Emissions, sm/mi
Test Test '
Proc. Mileaae KC
1975 i 0
CO
0.43 ' 1.92
2. 030 0. 23 ' 1. 59
1975
0
0.12 2. IS
; i PTX-416 | ' 600 0.29 1.33
Xoble/Mono
; PTX-416
Noble/.\!T.io
! - PTX-416
: | '
l
Noble/Mono
i
X
X
)
{Stacked Substrate)
Noble/Mono
PTX-4 '
Xoble/Mono '
PTX
1 Xoble/Mono
PTX-423S (2)
. (0. 2iro Pt) . .
1975 0 ! 0. 11
['75
2, vOO i 0. 36
1.55
2.13
0 0.21 2 17
25, 344
i
197 =
197:
1975
1975
1975
1975
0
8, 000
10. 353
50, 000
24, 000
0
8, 424
21, 527
0
70, 000
C. 24
0.29
0.35
0.323
0. 75
0. 13
0. 51
0. 55
0.23
0.85b
2.45
4. 10
3. 93
4.803
8. 57
1.9
4.9
5. 5
2.7
8.7b
i
0. 15
1.3
aLeast squares straight line value Average of two tests ' ' g
NO
X
2.60
.2.90
2. 12
3.82
2.48
0.79
1. 31
1. 82
3.82
3.79
1.45
2.75
1. 3
1.4
1.6
1. 5
3.5b
3.3
P err.arks
Volvo {Ref. 5-40, 5-46)
1
Int. Harvester (Ref. 5-471
Loose substrate
AM. Motors (Ref. 5-48)
Gen. Motors (Ref. 5-45)
After completion of high
speed tire test 70,000-mi
run at Arizona track.
Same car - Fresh
PTX 423S catalysts
5-85
-------
Table 5-13. Engelhard Catalyst DataBritish Ley-land
Car
Austin Marina (A)
Austin Marina (A)
Triumph GT-6 (C)
Triumph Spitfire (D)
TR-6 (E)
Jaguar XJ-6 (F)
Mileage
0
ll,400b
11,450
17, 000b
0
4, 000
0
0
0
0
4, 100
EGR
No
No
No
No
No
No
No
No
No
Yes
Yes
Emissions, gm/mia
HC CO NOX '
0.11 1.78 1.86
0.28 2.73 2.32
0.34 2.08 1.65
0.63 4.65 1.32
0.04 1.49 1.67
0.098 0.92 2.27
0.58 1.78 2.04
0.50 1.95 L.87
0.39 5.10 1.75
0.08 2.80 0.86
0.15 3.00 1.10
a!975 CVS-CH test procedure
Valve recession; new head fitted after test
-------
Table 5-14. Engelhard Catalyst Data--Saab Scania
Test
No.
1
2
3
Vehicle
No.
340
340
271
Fuel
System
El. Inj.
El. Inj.
Carb.
Air
Injection
Yes
Yes
Yes
EGR
No
No
On - Off
Driving
Cycle
Normal
Normal
MARC
Mileage
0
4, 550b
0
l,770b
0
7, 700b
Emissions, gm/mia
NO
HC CO x
0.61 5.72 1.46
1.22 17.7 1.48
0.33 4.32 1.12
0.95 16.51 1.34
0.43 2.99 0.96
0.87 15.12 0.95
a!975 CVS-CH test procedure
Catalyst insert loose
Mileage accumulation route (ave. speed = 32 mph, highest speed = 55 mph, 16 hr/day)
Ui
I
oo
-------
Table 5-15. Engelhard Catalyst D'ata--Dairnler Benz
Test
Date
12-9-71
12-10-71
12-16-71
1-31-72
10-27-71
10-29-71
11-3-71
11-4-71
11-11-71
11-11-71
11-12-71
11-12-71
11-15-71
11-10-71
11-10-71
11-16-71
11-18-71
11-24-71
12-8-71
12-9-71
Test
No.
1778
1788
1818
2032
1579
1591
1574
1611
1632
1636
1639
1640
1644
1655
1657
1679.
1683
1710
1770
1780
Car
Model
220V25
220V25
220V25
220VL5
250CE
250
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE
250CE "-
250CE
250CE
250CE
License
Plate
114E73
S-J8529
114E73
114E73
114E73
114E73
114E73
114E73
114E73
114E73
114E73
S-J8191
114E73
114E73
114E73
114E73
f
Emissions, gm/mi
HC
0. 38
0.25
0.41
0.23
0.75
0.. 24
0.30
0.36
0.51
0.22
0.35
0.27
0. 36
0.51
0.45
0,73
0. 35
0.56
0.36
0. 34
CO
3.48
2.04
8.19
2.84
5.43
1.85
1.57
1.74
1.13
1.85
2.. 09
2.69
2.69
3.69
1.83
1.73
3.50
4.39
3.06
3.52
NO
X
0.61
0.72
0.61
0.44
1.16
1.69
1.84
1.97
1.72
1.94
2.15
1.27
2.01
1.65
1.55
1.82
2.16
2.12
1.82
2.20
Oxidize r Catalyst
Englehard
Engelhard
Engelhard
Engelhard
Engelhard PTX-4.4.5
Engelhard 2 PTX-4,
PTX-5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4.4.5
Engelhard PTX-4
Vehicle
Mass
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
3500
4000
4000
4000
3500
4000
I
00
00
-------
Table 5-15. Engelhard Catalyst Data--Daimler Benz (Continued)
Test
Date
12-10-71
12-14-71
12-17-71
1-24-72
1-26-72
3-6-72
12-14-71
1-4-71
1-7-72
1-10-72
1-27-72
1-27-72
2-2-72 -
2-3-72
2-8-72
2-9-72
2-10-72
2-11-72
2-16-72
2-15-72
Test
No.
1791
1805
1827
1997
2015
2208
1807
1873
1911
1912
2012
2Q20
2028
2057
2072
2076
2079
2084
2085
2099
Car
Model
250
250
250CE
250CE
280
250CE
W108
W108
450
450
W108
W.1.08 .
W1.08.
W108
W108
W108 .
W108
W108
W108
W108
License
Plate
S-J8529
S-J8191
114E73
114E73
S-J8191
114E73
E60
E60
. E60
. ~. .
*fr
Emissions, gm/mi'
HC
0, 30
0, 33
0. 33
0. 31
0,68
0.33
0.47
0.35
0.20
0.31
0.40
.0.48
0. 11
0.13
0. 17
0.22
0.16
0. 19
0.12
0. 14
CO
3.04
3. 18
3. 16
3.99
7.21
7.66
3.99
4.32
3.37
4.09
3.62
, 1.49
3,. 42
2.08
2.41
2.81
1.88
1.90
2.35
2.87
NO
X
1.89
1.36
1.88
2.97
2. 24
2.95
1.60
1.75
2.05
2.08.
2.34
. 2. ..5.9
1.91
1.82
1.70
1.61
1.57
1.23
1.19
1. 18
Oxidizer Catalyst
Engelhard 2 PTX-4,
PTX-5
Engelhard 2 PTX-4,
PTX-5
Engelhard PTX-4
Engelhard PTX-4
Engelhard PTX-4
Engelhard PTX-4
Engelhard
Engelhard
Engelhard
Engelhard
Engelhard 4 PTX-4
Engelhard 4. PTX-4
Engelhard 4 PTX-4
Engelhard
Engelhard 4 PTX- 4
Engelhard 4 PTX-4
Engelhard
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Engelhard 4 PTX-4
Vehicle
Mass
3500
3500
4000
4000
4000
4000
4000
4000
4000
4000
4000
.4000 ..
4000
4000 -.
4000
4000
4000
4000
4000
4000
-------
Table 5-15. Engelhard Catalyst Data--Daimler Benz (Continued)
Ul
I
vO
o
Test
Date
2-18-72
2-'25-72
3-3-72
3-7-72
Test
No.
2110
2151
2197
2204
Car
Model
W108
W108
W108
W108
License
Plate
E60
$
Emissions, gm/mi
HC
0.13
0. 22
0^13
6.10
CO
2.45
3'. 81
5. 56
3.17
NO
X
1. 35
1. 17
0.97
1.44
Oxidizer Catalyst
Engelhard 4 PTX-4
Engelhard
Engelhard 4 PTX-4
Engelhard PTX-4
Vehicle
Mass
4000
4000
4000
4000
* 1975 CVS -CH test procedure
-------
Table 5-16a. Engelhard Catalyst Data - Ford Riverside Program
(Group I Single Catalyst) (Ref. 5-35)
.Vehicles
250 Maverick -1
(1) PTX-6. 35
250 Maverick -2
351 Ford -1
(2) PTX-5. 35
351 Ford -2
360 F-100 -1
(1) PTX-7. 35
360 F-100 -2
460 Lincoln -1
(2) PTX-6. 35
460 Lincoln -2
Average:
\
0 Miles
HC CO NO
X
0.41 2.23 2.45
0.32 0.95 2.92
0.19 1.91 2.34
0.2 1.75 2.46
0.55 4.42 2.30
0.49 2.83 2.45
0.63 3.21 2.36
0.43 2.88 2.16
0.40 2.52 2.43
2000 Miles
HC CO NO
X
0.58 3.28 2.96
0.35 1.37 4.2
0.43 3.17 2.47
0.22 2.32 2.75
0.47 3.82 2.55
0.36 2.41 2.81
0. 54 3. 52 2. 25
0. 54 3. 39 2. 31
0.44 2.91 2.79
4000 Miles
HC CO NO
X
0.63 3.56 3.48
0.42 3.19 3.04
0.25 1.91 2.56
0. 32 2. 29 2. 89
0. 38 4. 4 2. 47
0.33 2.11 2.74
0.6 3.21 2.35
0.7 4.43 2.51
0.45 3.14 2.76
0-4000 Mile
Deterioration Factor
HC CO NO
X
1.5 1.68 1.52
1.34 3.53 1.03
1 . 49 0. 9 1 . 09
1.65 1.29 1.17
0.69 0.93 1.07
0.65 0.74 1.12
0.96 1.0 0.95
1.13 1.55 1.14
1.18 1.45 1.14
Note: Emission values (in grams per mile) are the average of two consecutive 1975 CVS-CH Tests.
I
sO
-------
Table 5-l6b. Engelhard Catalyst Data Ford Riverside Program
(Group II, Extra Catalyst with Reactor) (Ref. 5-35)
Vehicles
250 Maverick -1
(Z) PTX-6.35
250 Maverick -2
351 Ford -1
(2) PTX-5. 35
(1) PTX-7. 35
351 Ford -2
360 F-100 -1
(2) PTX-7. 35
360 F-100 -2
460 Lincoln -1
(2) PTX-6. 35'
(1) PTX-7. 35
460 Lincoln -2
Average:
0 Miles
HC CO NO
X
0.22 3.23 1.76
0.54 8.74 1.68
0.36 3.72 2.17
0.32 4.21 1.76
0.38 4.45 1.44
0.24 3.96 3.12
0. 23 2. 22 2. 33
0,32 4.51 1.97
0. 33 4. 38 2. 03
2000 Miles
HC CO NO
X
0.32 2.98 2.02
0.49 9.79 1.83
0.27 2.93 2.06
0.4 4.65 1.88
0.39 4.99 1.62
0. 25 3. 43 2. 55
0. 27 4. 29 2. 63
0.35 6.28 2.02
0.34 4.92 2.08
4000 Miles
HC CO NOx
0.40 4.82 2.08
0.32 5.58 1.57
0.4 5.63 1.75
0.26 3.16 1.91
0. 26 3. 58 2. 33
0.37 5.6 2.17
0. 34 4. 62 2. 09
0-4000 Mile
Deterioration Factor
HC CO NO
X
1.07 1.03 1.23
1.13 1.51 1.0
1.17 1.22 1.11
1.12 1.25 1.11
Note: Emission values (in grams per mile) are the average of two consecutive 1975 CVS-CH tests.
(Jl
I
ru
-------
Table 5-16c. Engelhard Catalyst Data Ford Riverside Program
(Group III, Extra Catalyst) (Ref. 5-35)
Vehicles
250 Maverick -1
(2) PTX - 6. 35
250 Maverick -2
351 Ford -1
(2) PTX - 5. 35
(1) PTX - 7. 35
351 Ford -2
360 F-100 -1
(2) PTX - 7. 35
360 F-100 -2
460 Lincoln -1
(2) PTX - 6. 35
(1) PTX - 7. 35
460 Lincoln -2
Average:
0 Miles
HC CO NO
0.32 0.6 2.34
0.21 1.73 2.08
0.17 1.77 2.26
0.26 1.53 2.19
0.34 4.71 2.05
0.32 1.71 2.09
0.28 1.59 2.1
0.24 4.26 2.18
0.27 2.24 2.16
2000 Miles
HC CO NO
X
0.31 1.11 3.09
0.6 2.18 2.7
0.2 1.51 2.2
0.34 1.46 2.26
0.40 4.01 1.98
0.24 1.08 2.24
0.31 3.35 2.59
0.31 5.68 1.99
0.36 2.59 2.35
4000 Miles
HC CO NO
X
0.37 0.95 3.36
0.28 1.56 2.45
0-4000 Miles
Deterioration Factor
HC CO NO
1.02 1.71 1.59
Note: Emission values (in grams per mile) are the average of the consecutive 1975 CVS-CH tests.
Ul
I
U)
-------
Table 5-l6d. Engelhard Catalyst Data Ford Riverside Program
(Group I, Single Catalyst)
Vehicle
250 Maverick C-l
(1) PTX - 6. 35
250 Maverick C-2
(1) PTX - 6. 35
351 Ford C-l
(2) PTX - 5. 35
351 Ford C-2
(2) PTX - 5. 35
360 F-100 C-l
(1) PTX - 7. 35
360 F-100 C-2
(1) PTX - 7. 35
460 Lincoln C-l
(2) PTX - 6. 35
460 Lincoln C-2
(2) PTX - 6. 35
HC
0.66
0.59
0. 33
0. 36
0,20
0. 30
0. 37
0. 26
0.62
0. 32
0. 34
0. 38
0.47
0. 61
0.94
0.46
CO
4000 Mile
3.36
3.76
2000 Mile
1. 12
1. 61
4000 Mile
1.69
2. 12
4000 Mile
2. 44
2. 13
2000 Mile
4. 37
3. 26
2000 Mile
2. 10
2. 72
2000 Mile
3. 22
3.82
4000 Mile
4.46
4. 39
Note: Emission values (in grams per
consecutive 1975 CVS-CH tests
NO
X
3.77
3. 19
3. 70
4.69
2.52
2. 60
2.77
3. 00
2.86
2.24
2.76
2. 85
2. 27
2. 23
2. 61
2.41
HC
0. 78
0.66
0. 41
0. 42
0. 25
0. 23
0. 24
0. 41
0. 34
0. 32
0. 33
0. 57
0. 63
0. 57
mile) are the ave
CO
8000 Mile
2. 28
2.37
4000 Mile
3. 60
2. 67
8000 Mile
1.84
2. 32
8000 Mile
2.45
4000 Mile
4. 21
4. 59
4000 Mile
2. 12
2. 09
4000 Mile
2.93
3.49
8000 Mile
3.63
rage of two
NO
X
3. 37
3. 46
3. 05
3.02
2. 55
2. 45
2.45
2.47
2. 46
2.72
2.76
2. 26
2. 44
2. 40
5-94
-------
Table 5-17. Engelhard Catalyst Data-Ford "1975 Durability Test Program" (Ref. 5-35)
Engine /Vehicle
Combination
12A90-D
1P38-D
1971 2.0L-2V A/T Pinto
IA58-D
1971 351W-2V A/T Ford
17A54-D
1971 351W A/T Ford
1L27-D
1971 460V A/T Lincoln
Syitem Description
AJ
X
X
X
X
X
CCR
X
X
X
X
X
Mod.
Garb.
X
X
X
X
TR
Type H
Phase I;
No core
Type H
Type H
Phase I
No core
Catalyst
PTX 5.35 (2)
PTX 5.35 (1)
PTX 5. 35 (R-Side)
PTX 5. 10 (L-Side)
PTX 5.35 (R-Side)
PTX 5.2 (L-Side)
PTX 6. 35 (2)
AMA
Durability
Mileage
0
1, 500
16, 500
0
25.000
25,000
0
45,000
0
35.000
Cold Emitiionf, gm/mi
HC
0.41
0. 17
0.23
3. 10
1.24
0.29
0.83
0.25
0.53
CO
4.68
6.84
3. 11
12. 13
11.48
8.36
15.09
3.82
3.66
X
0.70
1. 52
1.27
1.42
1.62
0.86
1.43
0.88
1.59
Hot Emissions, gm/mi
HC
0.28
0.07
0. 11
0. 10
3.08
0.67
0. 17
0.81
0.05
0.46
CO
1.39
0.23
7.25
1.41
9.43
5.66
2.61
6.98
2.70
3.61
NO
X
0.81
1.29
1.09
0.99
0.35
0.95
0.83
0.63
0.68
1.52
Remarks
Three port linera failed
After valve job
Reworked left reactor;
new head linen
U|»972-CVS-C test procedure
-------
Table 5-18. Grace Vehicle Emission Data (1975
CVS-CH Test Procedure)
Run No.
88
18
270
93
239
245
275
280
487
250
286
221
300
383
414
Catalyst
Designation
D45
D-45V
D-115
D-117
D-135
D-138
R-9119
D-139
D-142
D-501
R-9109
D-502
D-502
D-502
D-602
Vehicle
1970
1970
1971
1970
1970
1971
1971
1971
1970
1971
1971
1971
Catalyst Type
Pellet, Base
Pellet, Base
Pellet, Base
Pellet, Base
Pellet, Base
Pellet, Base
Pellet, Base
Pellet, Mix
Pellet, Base
Monolith, Base
Monolith, Mix
Monolith, Noble
Monolith, Noble
Monolith, Noble
Monolith, Noble
Catalyst
Volume,
in-^
300
300
300
300
300
300
300
300
300
70
70
51
51
36
36
Emissions,
Km /mi
HC
dS>
CQ» 2g^P
cgTjTD
cO£>
CUD
(QI^
(grrp
(§TFD
dP
d£>
dD
cs>
CjD
dz>
cGD
CO
5.90
4. 70
5. 37
6,41
3.99
4.94
CO3>
dTTp
3. 87
3.77
cO£>
SB>
COD
C2TjL>
3HP
Note:
Pellet Nominal 1 /8-in dia ball or extrudate
Monolith Ceramic (Cordierite) structure
Base Base metal catalytic agent
Noble Main catalytic agent of noble metal
Mix Main catalytic agent of base metal promoted by more than
trace quantity of noble metal
d_^) Values at or below 1975 emission standards
5-96
-------
5. 7. 5. 2 High Mileage Emissions
The only data received by Grace from automobile companies are results
reported by GM on two catalysts. One of these, Davex 45V, was aged for
50, 000 miles by the AMA durability procedure and the emission levels
determinedby the 1972 CVS-C procedure. The other catalyst, Davex42, was
aged for 50, 000 miles; however, no emission data were provided by Grace.
A standard 1970 vehicle -with a 350 cubic inch engine was used in these tests.
Figures 5-30 and 5-31 show the GM results translated to 1975 CVS-CH values
using a correlation developed by Grace for pellet catalysts (Ref. 5-5).
The 50,000 mile, 1975 CVS procedure levels for this catalyst are 0.6 gm/mi
hydrocarbons and 11 gm/mi carbon monoxide. Grace stated that it had
specified a temperature limit of 1600 F for this catalyst, but the catalyst
was exposed to temperature excursions as high as 2000 F and operated a
substantial portion of the time above 1600 F during the first 3000 miles. By
the end of the test the catalyst had undergone substantial shrinkage (but no
weight loss) and there was possible bypassing or channeling in the container.
To the best of Grace's knowledge, the 1970 vehicle used in this test was not
specially provided with low emission hardware other than air injection into
the exhaust manifold.
5. 7. 5. 3 Comparison with Auto Company Test Data
Applicable auto company data from Chrysler (Ref. 5-17), International
Harvester (Ref. 5-47), and General Motors (Ref. 5-45) are shown in Table 5-19.
The maximum mileage reported is 23, 000 miles.
5.7.6 Johnson-Matthey
Johnson-Matthey, the parent company of Matthey Bishop, has reported
(Ref. 5-13) results from a vehicle configured to demonstrate its catalytic
converter concept (noble metal/monolith). The test vehicle is a Chrysler
Avenger with a 1.5 liter GL, Plymouth Cricket engine designed to meet 1972
5-97
-------
14 i
M
t/m
O
ISSI
CD
MO
CO DETERIORATION FACTOR 1.32
ACEO ON AMA DURABILITY SCHEDULE
TESTED BY 1972 CVS-C PROCEDURE
DATA CONVERTED TO 1975 EQUIVALENTS
BY GRACE
10
20 25 30
MILES, thousands
35
40
45
50
Figure 5-30.
General Motors Durability Evaluation of Davex
45-V Catalyst (CO Emissions)
,
O
g/m
P
SSI
p
Ok
j
10
*
HC DETERIORATION FACTOR 1.38
AGED ON AMA DURABILITY SCHEDULE
TESTED BY 1972 CVS-C PROCEDURE
DATA CONVERTED TO 1975 EQUIVALENTS
BY GRACE
1 II II
20 25 30
MILES, thousands
35
40
45
50
Figure 5-31.
General Motors Durability Evaluation of Davex
45-V Catalyst (HC Emissions)
5-98
-------
Table 5-19. W.R. Grace Catalyst Data
5-105
Test No.
2
36
Car
No.
Car and/or CID
Chrysler
117
258
360
GD57E41/360
Int. Harvester
161
HOOD Travel.ll: V-345
General Motors
61336
61341
61340
61330
61324
2827
2823
1246
2014
2611
2484
1450
Chev 350
Chev 350
Chev 350
Chev 402
Chev 402
Buick 455
Buick 455
Cad 500
Old. 350
Old. 350
Old! 455
Opel 1.9 Liter
Test
Weight
4500
4500
4500
4500
4500
5000
5000
5500
4500
5000
5000
1500
Test
Date
7/71
8/71
8/71
10/71
6/71
2/72
1/72
1/72
2/72
3/72
4/72
2/72
3/72
4/72
2/72
3/72
12/71
1/72
2/72
System Description
AI
X
X
X
X
X
X
X
X
X
X
X
X
EGR
X
X
X
X
X
X
X
X
X
X
X
3C
Mod.
Garb.
X
X
X
X
X
X
X
X
EFE
X
TR
30T. Site
Catalyst
Noble/Mono Davex 47V
3 x 3-1/4 in. Discs (21
Base/Pellet Davex 45V
Noble /Mono {Spiral
Substrate!
Base/Pellets (Davex 1171
Base/Pellets (Davex 1171
Base/Pellets (Davex 1171
Base/Pellets (Davex 117)
Base/Pellets (Davex 1171
Base/Pellets Davex 142
SMR 7-3881
Base /Pellets Davex 142
SMR 7-3881
Base /Pellets Davex 117
Base/Pellet Davex 142
SMR-7-3881
Base /Pellet Davex 142
SMR-7-3881
Base/Pellet Davex 142
SMR-7-3881
Base/Pellet Davex 117
Test
Free.
1972
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
Test
Mileage
0
459
0
0
16.000
800
400
150
100
1,000
88
0
0
20
3.034
6.436
0
6.337
12.022
2
1,000
0
12,000
23,000
Emissions, gm/mi
HC
0.40
0.60
0.66
0.46
0.46
0.30
0.50
0.60
0.37
0.36
0.27
0.20
0.27
0.59
0.70
0.89
0.40
0.52
0.91
0.33
0.34
0.53
0.73
1.2
CO
8.3
5. 1
4. 1
5. 1
6.85
7.0
7.0
10.0
12.8
4.1
4.2
4.7
1.7
11.1
11.6
15.5
9.0
17.7
24.0
6.5
6.4
10.4
10.8
22.9
NOX
1.01
1.41
5.93
4.51
3.99
1.3
1. 1
1.4
0.8
0.9
3.7
2.9
2.9
2. 1
2.0
2.9
2.3
2.4
2.2
3.9
3.2
1.7
2.2
2.5
Remarks
(Arvin co-op)
(Norria co-op)
(Walker co-op)
vD
-------
emission regulations, equipped with Stromberg CD2SE low emission
carburetor and vacuum advance-retard distributor. It is modified to a low
compression engine (8:1) with improved valve seats for use with lead-free
fuel. The modifications include an EGR system, and a manifold air oxidation
system designed by Ricardo & Company Engineers, Limited, equipped with a
3
Lucas AP1F air pump (4 ft /min at 850 rpm running at 1:1 engine speed) and
a Smith air dump valve for deceleration modes.
An AEC3A catalyst is used in the current test program. It has ceramic
monolith supports for low pressure drop, high thermal and mechanical shock
resistance, low attrition loss, and low thermal mass. The support is treated
with a proprietary -wash coat to increase the area available for deposition of
the active catalyst. The catalyst formulation is based on promoted platinum
metals for increased effectiveness.
Johnson-Matthey reports that with these engine modifications vehicle
driveability is not significantly impaired; however, performance of the vehicle
decrease marginally due to the use of EGR and the pressure drop in the
catalyst unit. The fuel penalty incurred is not expected to be more than
5 percent, and possibly less than 3 percent. The gasoline used for the
endurance test has a reported lead content of 0. 000563 gm/gal.
The vehicle has been tested according to the 1975 CVS-CH test procedure.
The breakdown of CVS tests is quoted for reference, giving the total emissions
(in grams) for the three exhaust bags: cold transient (first 505 seconds^cold
stabilized (rest of driving cycle),and hot transient (second 505 seconds).
Johnson-Matthey intends to continue this road test until 50, 000 miles have
been completed or until the level of emissions exceeds 1975 standards.
5.7.6. 1 Durability Test Results
The emissions over the 1975 CVS-CH Test procedure for the first 24,000
miles of the durability run are presented in Table 5-20. A complete breakdown
of emissions for the three bags is presented in Table 5-21. The CO and NO
5-100
-------
Table 5-20. Johnson-Matthey Avenger Durability Results
(Catalyst EC 3A/4 - E/BA25/90
Miles
0
500
1,000
2,000
3,000
4,000
6, 000
8,000
10,000
12,000, preservice
12,000, post-service
16,000
20,000
24,000, preservice
He'1'
0. 11
0. 09
0. 106
0. 16
0. 15
0. 15
0. 19
0. 17
0. 19
0. 21
0. 21
0. 30
0. 26
0. 33
'1975-CVS-CH test procedure; emissions
co(l)
0. 85
0.58
1. 03
0. 75
0. 88
0.91
0.91
0. 73
0. 51
0. 74
0. 71
0. 74
1. 06
1. 33
in gm/mi.
NO ^*
X
1.65
1.93
2. 16
2. 07
1.84
1.81
2. 10
2.09
2. 03
1.77
1. 50
2. 04
1.76
2.01
5-101
-------
Table 5-21. John son-Matthey Avenger Durability Complete
Bag Results for Catalyst EC 3A/4 - E/BA25/90
Miles
0
500
1,000
2,000
3,000
4, 000
6,000
8,000
Emissions
HC
CT
cs
HT
sw
CT
CS
HT
sw
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
sw
CT
CS
HT
sw
CT
CS
HT
SW
1.
0.
0.
0.
0.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
40
15
19
11
81
19
24
09
06
19
25
106
36
37
4
16
40
29
42
15
47
25
38
15
78
41
44
19
25
43
61
17
11
1
0
0
7
1
0
0
11
2
1
1
10
1
0
0
11
0
1
0
12
0
1
0
12
1
0
0
8
1
1
0
CO
.70
.01
.61
. 85
.01
.00
.59
. 581
.73
.02
. 18
.03
.00
.01
.6
. 75
. 54
.99
. 17
. 88
. 05
.99
. 16
.91
.77
.00
.59
.91
.8
.01
. 19
.73
NOX
6.
4.
8.
1.
8.
5.
8.
1.
8.
6.
10.
2.
9.
6.
9.
2.
7.
5.
8.
1.
8.
5.
7.
1.
8.
6.
9.
.2.
9.
6.
9.
2.
60
96
08
65
38
77
93
93
98
28
65
16
7
1
2
7
49
72
53
84
7
5
66
81
95
53
43
10
15
49
22
09
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
gm
gm
gm
gm /mi
gm
gm
gm
gm /mi
gm
gm
gm
gm
gm
gm
gm
gm/mi
gm
gm
gm
gm /mi
gm
gm
gm
gm /mi
5-102
-------
Table 5-21. Johnson-Matthey Avenger Durability Complete
Bag Results for Catalyst EC 3A/4 - E/BA25/90
(Continued)
Miles
10,000
12,000, preservice
12,000, post-service
16,000
20,000
24,000, preservice
Emissions
HC
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
SW
CT
CS
HT
SW
CT Cold transient
CS Cold stabilized
HT Hot transient
SW Sum weighted
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
0.
0.
1.
0.
1.
0.
1.
0.
0.
0.
2.
0.
0.
0.
06
55
80
19
72
46
73
21
66
46
74
21
79
90
03
30
89
66
88
26
52
85
95
33
CO
4.
1.
1.
0.
8.
1.
1.
0.
8.
1.
1.
0.
8.
1.
1.
0.
13.
0.
1.
1.
18.
1.
1.
1.
83
04
22
51
86
02
2
74
37
03
21
71
22
01
77
74
91
99
75
06
43
02
80
33
NOX
9.
6.
8.
2.
7.
6.
6.
1.
8.
6.
8.
1.
9.
6.
8.
2.
7.
5.
8.
1.
8.
6.
9.
2.
01
45
67
04
92
21
48
77
83
08
93
49
03
38
91
04
10
55
14
76
28
33
13
01
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
gm
gm
gm
gm/mi
5-103
-------
emissions are relatively constant over the test run whereas HC emissions
are rising. The cause of increased HC emission is currently under investi-
gation. These data trends are shown graphically in Section 3. 1. 7.
5. 7. 6. 2 Comparison with Auto Company Test Data
Applicable auto company test data for Johnson-Matthey catalysts are shown
in Table 5-22 for British Leyland (Ref. 5-23), Volvo (Ref. 5-46), Daimler-
Benz (Ref. 5-49), and Saab-Scania (Ref. 5-33). The maximum mileage
reported is 2520 miles (Saab).
5.7.7 Monsanto
Monsanto was not a participant in the Suspension Hearings and did not
provide background information to EPA.
Chrysler (Ref. 5-17), Saab-Scania (Ref. 5-33), and General Motors (Ref. 5-45)
did provide emission test data for Monsanto base metal/pellet catalysts they
had evaluated. The data are summarized in Table 5-23.
5.7.8 Oxy-Catalyst
Oxy-Catalyst does not perform vehicle emission tests and therefore relies
on auto company data. The tests conducted on their catalysts by the automobile
manufacturers consist of engine dynamometer performance tests, car
performance tests, and durability tests.
5. 7. 8. 1 Low Mileage Emissions
Oxy-Catalyst's latest catalyst (HN-1429) performance data (Ref. 5-7) are
tabulated in Table 5-24.
5. 7. 8. 2 High Mileage Emissions
The latest test results on durability received from GM (Ref. 5-7) for the
HN-1429 catalyst show that after 4600 miles, the emissions have increased
to 3.8 gm/mi CO and 0. 36 gm/mi HC. On earlier generations of catalyst,
5-104
-------
Table 5-22. Johnson-Matthey Catalyst Data
Test No.
467
616
1020
ioei
1102
2180
2245
2264
4
5
Car No.
OB44448
OB50424
OBS0840
Ml
311
Car and/or CID
MGB
Jaguar XJ-6
1072 model 144: engine B20F
1972 model 144: engine B20F
1072 model 144: engine B20F
WI08
WI08
W108
2.0 liter
2.0 liter
Test
Weight
4000
4000
4000
Teit
Date
12/2'71
1/11/72
3/17/72
3/20/72
4/10/72
2/20/72
3/13/72
3/16/72
System Description
A!
X
X
X
X
X
X
*
EGR
X
Mod.
Carb.
EFE
TR
Catalyst
Noble /Mono: JM
Noble /Mono: JM
Noble /Mono: JM AEC 3 A
Noble/Mono: JM AEC 3A
Noble /Mono: JM AEC 3 A
Noble /Mono: JM AEC 3 A
Noble/Mono. JM AEC 3A
Noble /Mono: JM
Noble/Mono: JM
Noble /Mono: JM
Noble /Mono: JM
Noble /Mono: JM
Test
Proe.
1975
1975
1975
1975
1975
1975
1975
1975
1075
1975
Test
Mileage
0
0
100
1.300
0
750
0
0
995
0
2.520
Emissions, gm/mi
HC
0. 14
0.20
0. 19
0.72
0.17
0. 17
0.31
0. 11
0. 13
0. 15
0.30
0.21
0.21
0.32
CO
1.02
2.50
1.56
4.28
1.52
1.25
3.28
2.34
2.67
1.72
1.73
1.95
2.32
4.67
NOX
2.41
1.00
3.32
3.65
2.46
2.41
O.S
1. 14
0.81
0.83
2.23
2.00
1.95
1.75
Remarks
Brit. Leyland
Brit. Leyland
Volvo
Honeycomb Broken
Volvo
Honeycomb Broken
Volvo
Daimler-Benz
Daimler-Benz
Daimler-Benz
Saab
Catalyst Loose
Saab
Catalyst Loose
o
U1
-------
Table 5-23. Monsanto Catalyst Data
i
H*
O
Test No.
1
2
8
9
10
Car No.
259
314
385
341
1938
61125
2828
61206
61329
61201
Or and /or C1D
360
2.0 liter
1.85 liter
2.0 liter
Pontiac 455
Buick 455
Buick 455
Cadillac 472
Chevrolet 402
Cadillac 472
Test
Weight
4500
5000
5000
5500
4500
5500
Ten
Date
12/71
2/72
3/72
2/72
7/71
4/72
zm
3/72
System Description
AI
x
X
X
X
X
X
X
X
X
EGR
X
X
X
X
X
X
»
X
Mod.
Carb.
Elect.
Inject
Elect.
Inject
X
X
X
X
X
EFE
X
X
X
TR
30% Slie
Catalyst
Base/Pellet (ECA 302)
Base /Pellet
(Monsanto 404)
Base/Pellet
Bate /Pellet
Base/Pellet (ECA-125)
Base/Pellet (ECA-125)
Base /Pellet (ECA- 141 1
Base/Pellet (ECA-125)
Base /Pellet (NBP-701941
Base /Pellet (ECA. 1251
Test
Proc.
1972
1975
1975
1975
1975
1975
1975
1975
1975
1975
Test
Mileage
0
27
0
248
0
9.750
0
2,050
400
2.500
0
1,200
126
5.550
1.000
1.500
Emissions, gm/mi
HC
0.30
0.34
0.26
-
0.22
0.50
0.31
0.61
0.41
1.0
0. 14
0.51
0.47
0.55
0.92
1.80
CO
4.5
3.5
3.03
-
1.44
2.97
1.61
4.16
5.4
7.6
3.8
4.6
4.0
6.8
6.8
8.8
NO,
1.39
1.34
1.10
-
2.37
2.87
1.75
1.58
1.5
0.9
3.1
0.9 .
1. 1
1.1
0.9
0.8
Remarks
Chrysler
Saab
Teat Continuing
Saab
Test Continuing,
Mar Cycle
Saab
Test Continuing
CM
CM
CM
CM
CM
CM
-------
Table 5-24. GM Evaluation of Oxy-Catalyst Catalyst
(Low Mileage Emissions Data)'a)
TestNo.(b)
1
2
3
4
5
6
7
8
9
10
11
12
Average
Emission results with
(0 mi) are:
Catalyst
1
2
3
3
4
5
6
7
(a) Prototype vehicle
Emissions,
HC
0.28
0. 20
0. 28
0.38
0.32
0.34
0. 29
0.41
0. 34
0.33
0.33
0.33
0.32
different fresh catalyst
Emissions,
HC
0. 30
0. 30
0. 30
0. 26
0.34
0.20
0.23
0. 20
without EGR
gm/mi
CO
1.7
1.6
3.0
1.7
2.2
2.1
3.3
2.4
2.4
2.5
5.4
3. 5
2.68
formulations
gm/mi(c)
CO
5.0
2.7
3. 5
2. 5
3.9
3.2
2.3
1.9
(b) These were repeat tests made with a fresh HN- 1429
catalyst
(c) 1975 CVS-CH
5-107
-------
durability tests of up to 33, 000 miles indicate catalyst hot cycle efficiencies
decline from 98 percent initially to an average stable level of about 60 percent
within the first 15, 000 miles (see Figure 5-32). The fuel used in testing con-
tained 0. 02 gm/gal lead, 0. 004 gm/gal phosphorus, and 0. 04 percent by
weight sulphur.
5. 7. 8. 3 Comparison with Auto Company Test Data
Data submitted by General Mx>tors (Ref. 5-45) concerning its vehicle test
evaluations of Oxy-Catalyst catalysts are shown in Table 5-25.
5.7.9 Union Carbide
Union Carbide did not provide catalyst emission data; no auto company
evaluations of Union Carbide catalysts are reported.
5.7. 10 Universal Oil Products
5.7. 10. 1 Emission Data - Low and High Mileage
Universal Oil Products has performed many vehicle tests incorporating
catalyst systems. Universal Oil Products (Ref. 5-50) believes that a noble
metal pelleted catalyst is one of their best candidates. A durability test of
this catalyst on a 1971 vehicle gave the following results:
Estimated 1975 CVS-CH
Emissions, gm/mi
Mileage HC CO
8,000 0.36 1.46
16,500 0.28 0.81
21,933 0.47 2.65
This catalyst failed to meet the emission standards after about 20, 000 miles.
Universal Oil Products feels this catalyst failed to meet the standards
because of attrition from over-temperature conditions. It has since improved
the stability of this catalyst which it predicts should reduce this type of
attrition.
5-108
-------
Ul
I
100
90
S 80
70
60
50
40
AMA DURABILITY, CLEAR FUEL
CONVERSION EFFICIENCY
1972 CVS-C WITH EGR
f
5 10 15 20 25 30 35 40 45 50
MILES, 000
Figure 5-32. General Motors Durability Test of Oxy-Catalyst P-623
-------
Table 5-25. Oxy-Catalyst Catalyst Data
Tcit No.
Car No.
2822
2824
2825
933
61317
Dev
2541
2494
2249
2850
4231
Car and/or CID
Bulck 455
Buick 455
Bulck 455
Buick 455
Chevrolet 350
Chevrolet 400
Oldimobile 350
Oldsmobile 455
Oldimobile 455
Oldimobile 4S5
Buick 350
Test
Weight
5000
5000
5000
5000
4500
5000
5000
5000
4500
5500
4500
Teit
Date
1/72
1/72
3/72
11/71
10/71
3/72
12/71
3/72
3/72
4/72
1/72
4/72
1/72
4/72
1/72
4/72
2/72
4/72
SyBtem Description
AI
X
it
X
X
X
X
X
X
EGR
X
X
X
X
X
X
X
X
X
Mod.
Carb.
X
X
X
X
X
X
EFE
TR
Catalyit
Baie/Pellet (G-13131
Baie/Pellet [G. 13131
Baie/Pellet
Baie /Pellet
B.ie/Pellet (G-62J-711
Baie /Pellet
B»»e /Pellet
Baie /Pellet
Baie/Pellet
Baie/Pellet
Baie /Pellet
Teit
Proc.
1975
1915
1975
1975
1975
1975
1975
1975
1975
1975
1975
Teit
Mileage
0
0
0
0
0
32.014
0
5.544
9
3,103
0
9,280
54
6.400
0
18,000
0
7.600
Emiuioni, gm/mi
HC
0.41
0.33
0.31
0. 19
0.47
1.20
0. 19
0.51
0. 17
0.46
0.20
1.02
0.27
0.48
0.31
0.58
0.64
0.81
CO
5.7
3.0
4.6
1.8
6.7
13.6
2.0
5.4
2.7
7. 1
9.2
7.7
10.8
11.9
10.5
7.4
6.8
9.5
NO,
3.5
3.7
3.3
2.4
1.4
1.4
5.9
5.3
2.2
2. 1
3.2
3.3
1.7
1.3
2.0
-4
2.7
2.5
3.7
Remarks
-------
Universal Oil Products has also developed a noble metal monolithic oxidation
catalyst on which they reported no emission data. Ford is reportedly
interested in this catalyst.
The third candidate UOP has developed is a base metal pelleted catalyst on
which the following data were reported (Ref. 5-51):
1975 CVS-CH gm/mi
Baseline emissions* Zero miles 1500 miles 7722 miles
HC 1.12 0.14 0.19 0.08
CO 12.62 1.21 3.90 1.15
During this test, the CO did rise above the standard at about 1500 miles due
to, UOP feels, low temperature sulfur poisoning. Universal Oil Products
reduced the air/fuel ratio of the engine at 7180 miles to increase the catalyst
temperature. This reversed the deactivation and lowered the CO emissions
below the standard.
Table 5-26 summarizes representative emission data for various UOP
catalysts, as determined from tests performed by UOP (Ref. 5-51).
5.7.10.2 Catalyst Durability Road Test
Road tests to 25,000 miles on two cars equipped with the noble metal, pelleted
cataly.st system were recently completed in an EPA sponsored test conducted
by Olsen Laboratories (Ref. 5-9). The results of these runs are shown in
Table 5-27.
5.7.10.3 Retrofit Applicability
In low mileage tests (under 4000 miles) conducted by UOP (Ref. 5-39), 82
vehicles had emissions which represent an 85-percent reduction of the 90-
percent reduction required to meet the 1975 standards. Seven vehicles
actually met the 1975 standards. Data for these vehicles are shown in
Table 5-28.
^Vehicle without catalyst
5-111
-------
Table 5-26. Summary of Representative Catalyst Test
Data (from UOP Tests of UOP Catalysts)
Test
No.
Car
No.
Car and/or CID
1972 Buick Le Sabre
1971 Chev 350
1971 Chev 350
1971 Chev 550
1971 Chev 350
1»71 Ford 551
1971 Ford 351
1971 Ford 351
1972 Dat«un 510
19' 1 Chev 350
191 1 Chev 350
Alfc Romeo Z. 0 liter
14 cyl.l
197: Capri - 1.6 liter
1971 Capri . 1.0 liter
1971 Flat 1.6 liter
1971 Chev 151
1971 Chev 350
Test
Weight
Test
Date
' '72
12/71
10/71
11/71
11/71
12/71
12/71
2/72
3/72
3/72
3/72
3/72
3/72
4/72
4/72
System Description
A I
X
X
X
X
X
X
X
EGR
Mod.
Carb.
|
Fuel
rich
ETE
TR
Catalyst
PZ-214
:
PZ-224-M1
Tsst | Tel'.
Proc . : Mileage
1975 *SI
-..
known
!»75 eit ] 0 hr
12 hrs
PZ-224-M2 i T 0 hr
PZ-224.8605
PZ-1-214-2
PZ-I-215-1
PZ-1-221-M1
PZM-11711 J5' ODx3- long,
.PZM-7711 :5 OD x !" long,
PZM-9711 i5" OD x 3 ' long'
PZM-10711 15" OD x 3" long.
PZ-H5 (in 2 L'OP mini-
Jo inJ/banki
2294-163
1»7; ei!
107- e«t
1Q75 cst
0 hr
!2 hn
C- hr
Ohr
12 hrs
3 hr
0
rlr-.!.ssions , gtr./.T.i
X i CO i NO,
5.21 | 2.22 2.<>1
, i
5. P 0.90
0.2= 2.1?
0.-- i 1.35
o.o-
0.20
0."3
:.3S I
Rem&rkt
CM ccr.vr>r:«r
i
0.15 1.77 i CM converter i75'> air-
O.U-C.19 ' O.S8-1.36 i
'J.24-C.3S i 2.0-3.54
0.27 j 1.13
O.o= 5.51
0.:-9 1.65
0. f3
; 0.4"
19T= cst i i. 1?
^033 0. 36
1^,503 0.23
i 21.933
25.9S6
197? est
C
2200
12. =00.
2294-165 1=7? e.t 0
1
PZ-195
PZ-216
PZ-226
PZ-1-2I4L-1: aged or.
1971 Ford Calaxie
2441-112
P7.-Z14
PZ.|05
PZ-168
PZ.ZI6
PZ.1-Z16-M2
PZ-216
PZ-l'S
PZ.m
PZ.m
PZ-1-J14-): aj.d
2424-1CC
2424-SS
1»75 est
1975
1»75
12.50C.
0
4670
4 70
0
1200
1975 est
|
19T5 !
197! est 0
1.35
2.60
1.45
1. 46
0.31
0.47 I 2.65
0. 74
0.32
0.65
1.19
0.6 =
1.07
0.25-C.28
0. 16-C.24
0.04
0. 14
0.14
0.02
0.11
0.54
0.38
0.58
0.42
0.50
I
1«TS |
i
l»7f
0
0
0
0
3.»!
0.30
o.zo
0.45
0.14
'liC | 0.1!
7722 ; 0.06
j I'.JTf 0.30
Iciest 0 O.S-
i
2.46
1.07
1.7E
1.59
2. 10
1.59
0.54-2.1!
0.9°-2.0
1.00
4.91
2 03
0.84
2. 39
2.45
4.29
5.78
2.60
0.«9
5. SO
0.51
0.57
0.§6
1.21
-.25
1.1!
2.00
!.=
2.6-3.7
2.41
.2.33
1 °0
'2.63
2.4&
1.96
2.25
1.52
J.74
2.23
:.J?
"Monolithic
"Cold" only
Xoblf 'pellets
20-253". c«t»lv*t Ion
"Hot11 only
'Monolith - 'hot' only
"Monolith"
'Hot'1 only
VOP mini -verier
CM converter
1500°F for 30 min
CM convener
SO In' converter
60 In3 convener
;1> MIM-verter
t4O/4- K 1.7-1
i2> Mir.t-vtrtfrt
(4-J/4 H 1.4"1
<1. Mlni-vetier
'4.3/4' t.T'-
CN! converter
2.52
2.48
!.OC
i"»C . C.C4 f.5? 1 ?.47
o ; o.'o
rOOO 0.63
i.-2
-.5$ '.5^
After IMO°F recvclirtf
of b*^ temperature
More recycl.ni
Vcno i! OD« 3
per bank
Mono t? ' CD x ">"
per bank1
5-112
-------
Table 5-27. 2.5, 000 Mile Durability Tests of UOP Mini-Verier with
PT-A-S Catalyst (2-1965 Chevrolets, 327 CID)
Car and Mileage Point
Car #21b
0 Miles - Base
With Converter
- Emissions Removed
20, 000 Miles0- Base
- With.' Converter
- Emissions Removed
Car #22d
a
b
c
d
0 Miles - Base
- With Converter
- Emissions Removed
25, 000 Miles - Base
- With Converter
- Emissions Removed
Emissions,
HC
9.1
1.9
7.2 (79%)
16.7
5.6
11.1 (66%)
7.9
1.45
6.45 (82%)
26.85
5. 2
21.65 (81%)
1972 CVS-C test procedure
Unleaded fuel
Test concluded at 20, 500 miles. Total vehicle miles were
and vehicle deterioration made continuation impractical.
10 percent of miles on leaded fuel
/ -a
gm/rm
CO
92. 1
2.7
89.4
199.5
92.8
106.7
65.0
2.3
62.7
86.2
16.9
69.3
over
(97%)
(53%)
(96%)
(80%)
100, 000
5-113
-------
Table 5-28. UOP Summary of Emission Results
for Retrofitted Vehicles (Mileage
Less Than 4000 Miles)
Vehicle
Fiat 85
Fiat 1600b
Subaru FF-1
Datsun
71 Chevrolet
65 Chevrolet
71 AMC
Catalyst
216
216
195
216
214
226
195
Emissions, gm/mi
HC
0.40
0.36
0.21
0.22
0. 14
0.32
0.32
CO
1. 20
0. 57
2.74
0.77
1.21
0.58
1.3Q
a!975 CVS-CH Test Procedure bAverage of two tests
5-114
-------
5.7.10.4 25, 000 Mile Durability Tests
Five 25, 000-mile tests are currently being conducted by UOP; one of these
has been completed (Ref. 5-32). The results of this test are shown in
Figure 5-8. During the early stages of this test, fuel was alternated between
lead-free fuel at about 0. 03 gm/gal lead and fuel containing 2. 5 gm/gal lead.
Good catalyst recovery when operated on lead-free fuel is shown for both HC
and CO emissions. At about 19f000 miles, the vehicles were switched to
fuel containing 0. 05 gm/gal lead and 0. 01 gm/gal phosphorus. Catalyst
activity, as indicated by emission levels of HC and CO, remained virtually
constant over the balance of this 25, 000-mile run.
This test indicates the ability of this catalyst to remain active in spite of
occasional contamination from fuel additives and with continued operation on
fuel at the lead and phosphorus levels suggested in the recent proposed EPA
fuel additive regulations (Ref. 5-21).
5. 7. 10. 5 Comparison with Auto Company Test Data
A number of auto companies have provided UOP with the results of testing
UOP catalysts. These data are summarized in Table 5-29. Additional
emission test data are available from submissions made by the auto companies
during the Suspension Hearings. These data are summarized in Table 5-30.
5.7.11 Kali-Chemie
Kali-Chemie was not a participant in the EPA Suspension Hearings. A
limited amount of test data for its catalysts are available from Saab-Scania
(Ref. 5-33) and Daimler-Benz (Ref. 5-49), as shown in Table 5-31.
5.7. 12 Degussa
Degussa was not a participant in the EPA Suspension Hearings. A limited
amount of test data for their catalysts are available from Saab-Scania
(Ref. 5-33), Daimler-Benz (Ref. 5-49), and General Motors (Ref. 5-45), as
shown in Table 5-32.
5-115
-------
Table 5-29. Summary of UOP Catalyst Data (Received
by UOP from Automakers'! (Re:. 5-51)
Test
No.
Car
No.
Car and/or CID
1972 Isuzu; 110 CID
(PA 30D; 4 cyl)
Subaru FF-1; 1. 3 liter
Toyota; 1. 6 liter
Mitsubishi Colt
Saab 99EA; 1. 85 liter
Mazda 1.6 liter
Saab
Toyo Kogyo Capella
1.6 liter
Mitsubishi
Toyota; 1. 86 liter
Mitsubishi
Test
Weight
Test
Date
2/72
1/72
2/72
12/71
2/72
1/72
12/71
4/72
12/71
10/71
4/72
System Description
AI
X
K
X
X
X
X
EGR
X
X
Estimated
Mod.
Carb.
EFE
pTR
1 Er.-.issior.s . gm/rr.i :
Test | Test : | :
Catalyst Proc. Mileage : HC CO ! NOX Remarks
x ' PZ-165 19~?:: ; 0 ; C.24 ".61 i : ;."O? low-cro:ile converter: -.veic crack at 25CO rr.:U =
| 1975 i 1400 0.55 4.72 ,
PZ-226 ' 1Q75
0 ".il 2.6 ' 3.5f . -; rc,r:-f-'!-r
! ! i i i
PZ-214 j 1975
PZ-l-214-2 i 1°72
FZ-216 1975
PZM-17121 i 1975"
PZM-17122
5;1 V. 59 r. 4o i i Mitsubishi converter
3000 1. 34 23. 7 j j
0.67 ". !": ; 0.~4 i UOP lo\v-Dro:'ile conx-erter, best carburetor setting
0. Q5 ?. 1? 1 . 3t 12r; leaner setting
403 j 0. 1° i. 1: ', 3. "7 VOP n-.i.-.i-verter .4-?'4 ' x 1.71".
1142 ,\23 2.01 5.45 ;
0.90 6.15 i Monolith
0.53 5.00 .\:onolith
PZ-226 1975 O.S7 7.C Tovo Kogvo container
PZ-214
PZ-195 1975"
PZ-216 1975
PZ-226
f Toyo converter 'i
PZ-226 1975
PZ-226 1975
PZ-226 1975':
PZ-216 1975
: ?.90 10.3 I Toyo Koeyo container
0 0.1° 4.2 i i Mini-vert'er (In in3!
0 0.16 2.77 0.QS Mini-verier 15-3/4" x 1.4"!
4180 0.39 4.55 1.53
0 0.48 1.34 i Hot CVS onlv
0 . 1.39 15. 2 Cole CVS only
0 0.05 1.04 Mitsubishi converter
0 j 0.33 3.57 j Toyota converter; 0.32 err..' gal lead
600 0.14 2.25 1 Mitsubishi converter
i 7000 i 0.25 4.3J ' Screen :aih:re at 3000 mi
i i i
.
5-116
-------
Table 5-30.
Summary of UOP Catalyst Data Submitted by
Auto Makers During Hearings
Test
No.
4
Q14
*f 14
080
200
602
692
Car No.
637
D08-6
OA34293
OB44065
Car and/or CID
Chrysler (360)
IRef 5-17)
AM. Motors (360-V8I
{Ref. 5-48)
IRef. 5-46)
Volvo IRel. 5-46)
Volvo (Ref. 5-46)
General Motors (Ref. 5-45)
61355
61358
62504
9168
8245
5274
8195
61201
2014
2611
61420
934
933
BAK
Chev 350
Chev 350
Pont. 455
Buick 455
Buick 455
Buick 455
Buick 455
Cad 472
Olds 350
Olds 350
Olds 455
Buick 455
Buick 455
Buick 455
Test
Weight
4000
4000
4500
5000
5000
5000
5000
5500
4500
5000
5000
5000
5000
5000
Test
Date
2/72
11/71
3/72
2/72
3/72
3/72
1/71
2/72
2/72
1/72
2/72
12/71
4/72
11/71
3/72
11/71
4/72
11/71
4/72
System Description
AI
x
x
X
X
X
X
X
»
X
»
X
X
ECR
X
X
X
X
X
X
X
X
X
X
x
X
X
Mod.
Carb.
X
X
X
X
X
X
X
X
x
X
EFE
X
pTR
.10*-. Sine
X
X
X
X
X
X
X
X
x
X
x
X
X
C»taly»t
UOP
(2, UOP mini-verter»
UOP noble Delict*
UOP
UOP
PZ-2-168 R-5 (Base/Pellets)
PZ-1-224-1 (Base/Pellets)
PZ-1-225-1 (Base/Pellets)
PZ-4-214 R-14 {Base/Pellets)
PZ-4-214 R-14 (Base/Pellets)
PZ-4-214 R-14 (Base/Pellets)
PZ-4-214 R-14 (Base/Pellets)
PZ-1-224-1 (Base/Pellets)
PZ-1-224-1 (Base/Pellets)
PZ-2-168-R-5 (Noble/Pellets)
PZ-1-224-1 (Base/Pellets)
PZ-4-2I4-R-I4 (Base/Pellets)
PZ-4-214-R-14 (Base/Pellets)
CVS
Te»t
Proc.
1972
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
1975
Test
Mileage
4000
195
125
375
0
5852
7000
700
80
100
650
300
300
1644
50
85
4552
1
6145
100
2287
0
18132
0
46.301
21
12980
Emissions, gm/mi
HC
0.8
0.39
0 13
0.19
0. 11
0.12
0.12
0.18
0.30
0.33
0.34
0.31
0.23
0.44
0.25
0. 16
0.52
0.95
0.24
1.4
0.20
0.17
0.25
1.49
0.19
0.78
0. 17
0.36
CO
2.9
2. SO
2 74
3.52
1.23
1.62
1.69
6.24
2.7
2.4
2.7
2.8
2.8
2.5
5.9
12.0
12.0
9. 1
14.6
2.6
3.2
2.7
14.7
1.8
11.7
2.8
6.6
NO,
3.0
3.20
3 62
3.23
2.20
2.15
1.24
1.26
0.8
0.9
0.9
1.7
1.4
1.5
1.0
1.0
2.3
2.4
1.9
2.6
1.0
1. 1
2.0
2.1
2.4
2. 1
3.7
1.6
Remarks
Couldn't control A/F
Reactor breakdown
Discontinued
Lost catalyst
Backfire damaged
mu er
Test stopped
(SI
I
-------
Table 5-31. Kali-Chemie Catalyst Test
(Base Metal/Pellets)
Auto
Co.
Saab
Saab
Daimler
Benz
Test
No.
6
7
2324
Vehicle
No.
301
301
Fuel
System
El. Inj.
El. Inj.
Air
Injection
Yes
Yes
EGR
No
No
Mileage
Type
MAR
MAR
Mileage
0
5,350b
0
5, 900°
Emissions, gm/mi
HC CO N°x
0.23 2.98 2.59
0.32 3.38 2.66
0.22 2.85 1.02
0.25 3.63 1.96
0.10 1.70 0.28
a!975 GVS-CH test procedure
Test continues
Container cracked
oo
-------
Table 5-32. Degussa;Catalyst Test Data
Base :Metfal/Pellets)
Auto
Co.
Saab
Daimler
Benz
GM
Test
No.
12 .
2377
2826
Vehicle
. ^ No.
301
Buick
455d
Fuel
System
El. Inj. .
Injectioti
Yes "'
Yes
EGR:
r No .'..
Yes
Mileage
- Type ;-
;" MAR;-.
-"
Mileage
;0 :
2, 58 Ob
10
*i
Emissions, g-m/mi
HC CQ : N°x
"o. 19 2±ll" 1.66
'0.74 15.;66"; 2. 52
0. 14 2.3 1.0
0.38 3.5 3.3
a!975 CVS-CH test procedure
Catalyst poisoned by phosphorus (4 ppm) in fuel
Mileage accumulation route
Degussa catalyst OM 56 ET . .
-------
5.7. 13 Imperial Chemical Industries
Imperial Chemical Industries was not a participant in the EPA Suspension
Hearings. However, British Leyland (Ref. 5-23) did provide emission test
data for ICI catalysts, as shown in Table 5-33.
5.7.14 AC-Delco
A number of auto companies presented emission test data results they
obtained when using AC-Delco converters containing base metal/pellet
catalysts. It is not known who supplied the pellets originally. The test data
are summarized in Table 5-34.
5.8 OVERTEMPERATURE PROTECTION SYSTEMS
Overtemperature protection systems of several types are proposed to provide
against overheating of the catalyst bed, overheating of the vehicle structure,
and causing fires. Catalyst bed temperatures normally run in the 1200-1400 F
range during normal operation. These temperatures can rise to 1700-1800 F
(Chrysler, Engelhard) during high speed driving and when pulling trailer loads.
Chrysler points out that catalyst overtemperature can result from a variety
of conditions, including, spark plug misfire, turning key off during deceler-
ation, high speed driving, pulling trailer loads, stuck choke, plugged air
cleaner, low carburetor float, and fuel boiling due to protracted idling.
Two basic approaches have been suggested by the automotive industry and are
under evaluation for providing the necessary catalyst overtemperature
protection. Both approaches employ a thermocouple signal to actuate the
control device.
One method is to control the secondary air supply to the catalytic converter.
Without the necessary oxidizing atmosphere, the catalyst would not function
efficiently and generate the normal temperature rise across the bed.
5-120
-------
Table 5-33. British Leyland Test Data
for ICI Catalysts
Car
f+
Austin Marina (A)
Austin Marina (A)
Mileage
0
6, 574
9, 200
0
4, 500
EGR
No
No
No
No
No
Emissions, gm/mi
HC CO N°x
0. 18 2. 29 2. 33
0,45 3,00 1.97b
0.20 2.61 2.21
0. 19 1.38 2.08
0.25 1.14 2.44
a!975 CVS test procedure CNoble /monolith
Valve recession, new head fitted after test Noble/pellets
-------
Table 5-34. AC-Delco Converters -- Emission Test Data Summary
Ul
i
ro
Tell
No.
806
852
732
809
C»r No.
American
D17-11
D27-1
nu. z
Dll-3
DI4-2
OOI-2B
Car and/or CID
Motort (Ref. 5-481
258-6
360-V8
360-V8
258-6
232-6
360-V8
Volvo (Ref. 5-461
OB44448
OBS0430
1972 Model 144
1972 Model 144
International Harveater (Ref. S-47)
156
393
MOOD Tr.v.Ull V-392
II 10 Travelall V.J92
Teat
Weight
3000
3500
4000
3500
3000
4000
Teit
Date
2/72
2/72
2/72
2/72
9/71
11/71
1/72
4/72
int.
4/71 '
System Deaeription
AI
X
X
X
X
X
X
K
«
"EOR
X
X
X
X
X
X
t
I
Mod.
Carb.
EFE
TR
Catalyat '
Baae/pelleta
Baae/pellett
Baie /pellet i
Baae /pellet*
Baae /pellet!
Bate /pellet!
Baie /pellet!
Baae /pellet!
Baae /pellets
Bate/pellet!
Bait /pellet!
BMe/ptlletl
B***7f*Hni
Teat
Proc.
197S
1975
1975
1975
1975
1975
1975
1975
197!
197!
.)>»
Teat
Mileage
32.000
0
0
0
0
12,000
150
339
120
3340
0
16.000
0
11.000
0~
1C. 000
Emiaiioni, gm/mi
' HC
0.39
0.50
0.39
0.23
0.23
1.21
0.39
0.38
0.24
0.39
0.45
0.83
0.3S
0.68
0.3S
O.SI
CO
3.04
5.01
6.09
1.47
2.38
16.94
3.50
2.40
2.43
5.75
4.4
11.4
4. 53
9.18
4.J6
8.76
NOx
1.50
3.24
2.83
2.12
3.28
4.33
4.54
4.57
3.14
3.47
2.96
2.59
2.49
2.29
j.h
3.00
Remark!
Actual teat point!
40% pellet Ion
30% pellet Ion
Suapeetcd inadvertent uae of
leaded fuel at 4000 milei
Converter recharged
Still in progreit
-------
The other method is to completely bypass the catalytic converter with the
exhaust gas. This approach would fully protect the catalyst (if actuated in
time), whereas the first approach still exposes the catalyst to the gas tem-
perature of the exhaust flow. Figures 5-33 and 5-34 illustrate one such
bypass system arrangement, as denoted by Chrysler for their A335 emission
control system (Ref. 5-17). It is designed to route exhaust gases around the
converter whenever 1500 F is exceeded.
In addition to these two protection system approaches, other refinements/
devices are also required. Electronic ignition systems are proposed to help
eliminate plug misfiring. The converter proper can be located sufficiently
far away from the exhaust manifold to reduce inlet gas temperatures. How-
ever, the farther away it is, the slower is the warmup of the bed under cold-
start conditions. Johnson-Matthey (Ref. 5-13) suggests the use of an air
dump-valve during periods of vehicle deceleration to minimize the catalyst
bed temperature.
With regard to vehicle structure protection heat shields are proposed for use
between the converters and the vehicle. General Motors (Ref. 5-16) proposes
insulators on top and bottom of its converter to protect against vehicle over-
heating as well as "grass fires".
The following illustrates current opinions of various companies relative to
the types of overtemperature protection systems proposed for 1975 vehicles:
a. Volvo prefers a warning system only; no bypass (Ref. 5-40).
b. VW has made no selection; a warning system (optical or
audible) may be included with perhaps an interlock to
prevent starting the car (Ref. 5-52).
c. Nissan is considering both bypass and secondary air control
(Ref. 5-53).
5-123
-------
Ui
i
ro
ELECTRIC
CHOKE
MODIFIED
FRAME RAIL
ALTITUDE
COMPENSATING
CARBURETOR
MONOLITHIC CATALYST
CONVERTER
CATALYST
BYPASS VALVE
EXHAUST MANIFOLD
REACTORS
AIR PUMP
EXHAUST
GAS RECIRCULATION
ELECTRONIC
ENGINE
CONTROL
BY-PASS PIPE STANDARD MUFFLER
Figure 5-33. Chrysler A-335 Special Emission Car (System Features)
-------
IR VALVE IN CATALYST POSITION:
ENGINE SPEED BELOW 2500 R.P.M.
CATALYST TEMPERATURE BELOW 1500° F.
FROM CATALYTIC CONVERTER
EXHAUST BYPASS
VACUUM CONTROL
TO MUFFLER
ACTUATOR
Figure 5-34. Chrysler Catalyst By-pass Valve
-------
d. British Ley-land prefers not to use bypass (although it
has used an experimental system); it utilizes thermo-
couples, warning lights and buzzers (Ref. 5-54).
e. GM has no bypass in its present plans; it incorporates a
choke which fails in the open position; it may use devices
in fuel metering and air flow devices to solve downhill
coast problems (Ref. 5-34).
f. Ford prefers to cut off the air supply to the converter
(using thermocouple for signal) (Ref. 5-35).
g. Chrysler has discarded air cut-off or air bypass to a
certain extent; it is developing a full bypass system
(Ref. 5-17).
5. 9 PROJECTED MAINTENANCE AND REPLACEMENT
PROCEDURES
Engelhard reports (Ref. 5-18) that its converters are presently designed to
be welded into the exhaust system. Firm details on other systems have not
been provided by other companies. Potential users of monolithic catalyst
beds have envisioned converter designs which enable simple cartridge-type
replacement of the monolithic bed.
In the past, potential users of converters incorporating pelletized catalyst-
beds projected the eventual possibility of being able to withdraw used pellets.
from the converter (by vacuum means, etc. ) and insert fresh or new pellets.
CHEMICO (Ref. 5-3) has now proposed the "topping off" of a converter
which has a reservoir of pellets above the pellets actually in use (similar
to hydraulic brake fluid reservoir); the topping-off would be accomplishedtat
regular servicing intervals.
UOP states (Ref. 5-39) that the spherical pellets used in their Mini-Verter
can be removed and replaced in a matter of minutes (comparable to an
oil change).
5-126
-------
In all cases, these are mere projections at the moment, with demonstrated
automotive application capability lacking. The exact method of catalytic
converter replacement* or refurbishment must await final selection of catalyst
material, final design of the converter canister, and evaluation of
replacement or refurbishment alternatives.
5.127
-------
REFERENCES
5-1 Air Products and Chemicals, Inc., Houdry Division, "Progress in
the Development of Automotive Emission Control Catalysts,"
13 April 1972.
5-2 American Cyanamid Company, "Statement by American Cyanamid
Company, Suspension Request Public Hearing, Environmental
Protection Agency, " Washington. D.C. , April 1972.
5-3 Chemical Construction Corporation (Chemico), "Statement to the
Environmental Protection Agency, Suspension Request Hearing,
Motor Vehicle Pollution Control," 21 April 1972.
5-4 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, "Summary Statement for EPA Hearings o* Volvo Application
for One-year Suspension of Auto Emission Standards, " 10 April 1972.
5-5 W. R. Grace and Company, "Presentation to the Environmental
Protection Agency Auto Exhaust Hearings," 5 April 1972.
5 -6 Matthey Bishop, Inc., "Testimony Presented to Environmental
Protection Agency, Washington, D.C. (with Technical Appendix), "
12 April 1972.
5-7 Oxy-Catalyst. Incorporated, "Testimony Presented to the
Environmental Protection Agency," 17 April 1972.
5-8 Union Carbide Corporation, Union Carbide letter to EPA regarding
information on emission control, 4 April 1972.
5-9 Universal Oil Products Company, "Summary of Data Pertinent to
Volvo's Request for Suspension of the 1975 Hydrocarbon and Carbon
Monoxide Standards for the Environmental Protection Agency, "
4 April 1972.
5-10 Aluminum Company of America, "Summary Statement to Environ-
mental Protection Agency," 11 April 1972.
5-11 American Lava Corporation, "Presentation to the Environmental
Protection Agency," Ann Arbor, Michigan, 3 April 1972.
5-12 Corning Glass Works, "Summary Statement for the Administrator,
Environmental Protection Agency," 20 March 1972.
5.128
-------
REFERENCES (continued)
5-13 Matthey Bishop, Inc. , Technical Data Submittal provided by
Matthey Bishop at the request of the EPA Suspension Request
Hearing Panel, 17 April 1972.
5-14 Kaiser Aluminum and Chemical Corporation, Kaiser Chemicals
Division, "Alumina Substrates for Auto Exhaust Emission Control
Catalysts," 30 March 1972.
5-15 Reynolds Metals Company, Technical Data Submittal provided by
Reynolds at the request of EPA, Ann Arbor, Michigan, April 1972.
5-16 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 17 April 1972.
- . i
5-17 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the
Clean Air Act, " March 1972.
5-18 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, Transcript of Proceedings -- Auto Emissions Extension --
Environmental Protection Agency, Washington, D. C. , 12 April 1972.
5-19 Ford Motor Company, Transcript of Proceedings -- Auto Emissions
Extensions -- Environmental Protection Agency, Washington, D. C. ,
19 April 1972.
5-20 Aerospace Corporation Report No. TOR-0172(2787)-2, "An
Assessment of the Effects of Lead Additives in Gasoline on Emission
Control Systems which Might Be Used to Meet the 1975-76 Motor
Vehicle Emission Standards," 15 November 1971.
5-21 Federal Register, "EPA - Regulation of Fuels and Fuel Additives -
Notice of Proposed Rule Making," Vol. 37, No. 36, Part III,
23 February 1972.
5-22 American Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 11 April 1972.
5-23 British Leyland Motors, Inc. , Technical Data Submittal provided by
British Leyland at the request of the EPA Suspension Request Hearing
Panel, 14 April 1972.
5-129
-------
REFERENCES (continued)
5-24 Chrysler Corporation, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D.C.,
20 April 1972.
5-25 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, "Technical Appendix to Summary Statement of Engelhard,
Addendum I, " 19 April 1972.
5-26 Saab-Scania, Inc., Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D.C.,
21 April 1972.
5-27 Toyota Motor Company, Ltd. , "A Summary of Toyota's Technology
and Processes for Meeting the 1975 Federal Emission Standards, "
5 April 1972.
5-28 Volvo, Inc. , Transcript of Proceedings -- Auto Emissions Extension -
Environmental Protection Agency, Washington, D. C. , 24 April 1972
(recall).
5-29 Volkswagen of America, Inc., Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 10 April 1972. , . .
5-30 Matthey Bishop, Inc., Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D.C. ,
13 April 1972.
5-31 Nissan Motor Corporation in U. S. A. (Datsun), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental
Protection Agency, Washington, D. C. , 11 April 1972.
5-32 Universal Oil Products Company, UOP Statement, EPA Hearings
on Proposed Lead Regulations, Los Angeles, California, 3 May 1972.
5-33 Saab-Scania of America, Inc. and Saab-Scania AB, "Information
Submitted in Response to Subpoena dated 17 March 1972 of Environ-
mental Protection Agency, Washington, D. C. "
5-34 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
5-130
-------
REFERENCES (continued)
5-35 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II,
5 April 1972.
5-36 Engelhard Industries, Inc. , Engelhard letter to the Aerospace
Corporation, October 1971.
5-37 Toyota Motor Company, Ltd., Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 13 April 1972.
5-38 American Lava Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 14 April 1972.
5-39 Universal Oil Products Company, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D.C., 18 April 1972.
5-40 AB Volvo, "Request for Suspension of the 1975 Emission Standards,"
9 March 1972.
5-41 Daimler-Benz AG, "Statement of Daimler-Benz AG Before the
Environmental Protection Agency, Washington, D. C. ," April 1972.
5-42 Volvo, Incorporated, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C. ,
10 April 1972.
5-43 American Cyanamid Company, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 18 April 1972.
5-44 Volkswagen of America, Inc. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 11 April 1972.
5-45 General Motors Corporation, Technical Data Submittal provided by
GM at the request of the EPA Suspension Request Hearing Panel,
21 April 1972.
5-46 AB Volvo, "Supplement to Request for Suspension of the 1975 Emissions
Standards," 15 April 1972.
5-131
-------
REFERENCES (continued)
5-47 International Harvester Company, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 14 April 1972.
5-48 American Motors Corporation, Technical Data Submittal provided by
AMC at the request of the EPA Suspension Request Hearing Panel,
20 April 1972.
5-49 Daimler-Benz AG, Technical Data Submittal provided by Daimler-
Benz at the request of the EPA Suspension Request Hearing Panel,
19 April 1972.
5-50 Universal Oil Products Company, "UOP Position Statement for EPA
Hearings on One-year Suspension of 1975 Automobile Emissions
Standards," 17 April 1972.
5-51 Universal Oil Products Company, Technical Data Submittal provided
by UOP at the request of the EPA Suspension Request Hearing Panel,
21 April 1972.
5-52 Volkswagen of America, Inc., "Information and Documentary Materials
Relating to Volkswagen's Emission Research and Design Effort to Meet
1975 Federal Emission Goals, " 10 April 1972.
5-53 Nissan Motor Company, Ltd. (Datsun), "Summary Statement of
Information, " 5 April 1972.
5-54 British Leyland Motors, Inc. , "EPA Hearing of Volvo Application
for Deferment of Emission Legislation Applicable to 1975 Model
Year Vehicles," March 1972.
5-132
-------
6. THERMAL REACTORS
6.1 SUMMARY DISCUSSION
The thermal reactor is a high-temperature chamber which replaces the
conventional engine exhaust manifold. Hot exhaust gases from the engine
enter the thermal reactor, which is sized and configured to increase the
residenc.e time of the gases and permit further oxidation reactions, thus
reducing the HC and CO concentrations.
In general, the thermal reactor embodies a double-walled insulated configura-
tion, with exhaust port liners to conserve the sensible heat in the exhaust gas
and to direct" the flow to the inner-core section of the reactor. In some
instances, baffles and/or swirl plates are used to promote mixing. Illustra-:
tions of two reactor designs, the DuPont Type V and the Esso RAM are
shown in Figures 6-1 and 6-2.
Whereas both rich and lean reactors have been considered and evaluated for
use in 1975 emission control systems, all of the reactors presently being
tested as potential 1975 candidate devices are designed for fuel-rich engine
operation. These systems require the addition of secondary air (usually
injected at the engine exhaust port) to promote the oxidation reactions in the
reactor.
With the exception of Toyo Kpgyo, no manufacturer proposes to use a full-size
thermal reactor device as a first-choice system component for 1975. The
General Motors and Chrysler systems utilize a partial (i.e. , a small,
simplified) reactor which serves primarily as a quick-heat device for rapid
warm-up of a catalytic converter. The Toyo Kogyo reactor is a prime
emission control component for this manufacturer's rotary engine system; in
6-1
-------
EXHAUST GAS
OUTER SHELL
RADIATION CORE
SHIELD
TO EXHAUST SYSTEM
Figure 6-1. DuPont Type V Thermal Reactor
EXHAUST
EXHAUST
EXHAUST
EXHAUST
FLAME
HOLDER
EXHAUST
Figure 6-2. Esso Rapid Action Manifold (RAM)
Reactor
6-2
-------
addition, it is one of several systems being evaluated for use on the Toyo
Kogyo 1975 reciprocating engine. Several manufacturers are evaluating
reactor devices as 1975 alternate system components.
Thermal reactor problems identified by the various manufacturers encompass
the following: (a) lack of sufficient emission control capability, (b) packaging
difficulties, (c) excessive underhood temperatures, and (d) lack of sufficient
reactor durability. In addition, durability problems continue to plague the
secondary air injection system. Numerous air pump replacements have been
reported by a number of manufacturers during the course of reactor durability
testing.
Severe engine damage has been caused by reentry of metal oxide particles
from the reactor core material through the EGR system into the engine lubricat-
ing oil. Such a problem was encountered in the DuPont test vehicle fleet
assigned to the California Air Resources Board for evaluation. DuPont is
currently investigating improved reactor core materials. A recent study by
Ford implies that a basic incompatibility may exist between thermal reactors
and catalytic converters when used together. Material deposits have been
found in the catalyst which are thought to originate in the reactor liner. These
deposits may contribute to the excessive deterioration observed in a number of
thermal reactor/catalytic converter emission control systems.
6.2 SPECIAL DESIGN FEATURES
6.2.1 American Motors
The use of a thermal reactor has been investigated by American Motors as a
possible alternate system. However, this manufacturer was unable to reach
the low level of emissions achieved with the catalytic converter system. This
fact, in combination with the major revisions to the vehicle front end that
would be required to accommodate the device, has resulted in a decision to
confine the 1975 development effort to a catalytic converter system (Refs. 6-1,
6-2).
6-3
-------
6.2.2 Chrysler
Chrysler has abandoned thermal reactors as a prime first- or second-choice
emission control system primarily because of lack of emission control poten-
tial and high-temperature material problems. The 1975 first-choice system
will utilize a partial thermal reactor which will function primarily to accele-
rate the warm-up of the catalytic converter under cold start conditions. The
Chrysler partial reactor is approximately one-third the volume of a full-size
DuPont-type system; further oxidation reactions are sustained in the down-
stream catalytic converter. The reactor design incorporates stainless steel
liners to help maintain high exhaust gas temperature and to promote mixing
and burning of the combustibles with the secondary air injected into the
exhaust ports.
Chrysler is looking for new lower cost core alloy materials with less nickel
content, but believes that it is two or three years away from a demonstration
of 50, 000-mile durability (Refs. 6-3, 6-4, 6-5).
6.2.3 Ford
Initially, Ford's first-choice system for 1975 was a combined thermal reactor/
catalyst system. Based on work during the past year, however, Ford believes
that the first-choice system ultimately will be a catalyst-only type. Emission
results with this system are nearly as good as those for the combined reactor-
catalyst system. The slight advantage in emission performance which the
reactor-catalyst system may provide is not considered commensurate with
the cost increase involved. A final first-choice system selection will be made
on completion of the Riverside test program when additional data on comparative
system performance will be available (Ref. 6-6).
/
The test series of 32 vehicles being conducted at Riverside includes eight
vehicles (Group II) that incorporate exhaust manifold reactors which function
primarily as preheaters for the catalytic converter. The Group II tests are
scheduled for completion in October 1972. Data for 4000 miles reported for
the Group II vehicles to data are presented in detail in Section 2.2.3.
6-4
-------
The effect of long-time exposure of components and materials to the thermal
reactor environment is being evaluated. A recent Ford experimental investiga-
tion identified material deposits which are thought to originate in the stainless
steel liner of the reactor. Investigations are under way to resolve this issue.
Ford speculates that a basic incompatibility may exist between thermal reactors
and catalytic converters used in combination.
Development reactors tested on six vehicles in the Ford 1975 model year
durability test program exhibited four failures at mileages ranging from 5000
to 30,000 miles (Ref. 6-6).
6.2.4 General Motors
Problems of temperature, space, and durability, as well as unsatisfactory
emission performance, have led General Motors to discard the thermal reactor
as a primary system for meeting the 1975 standards. Possible applications of
the thermal reactor to some specific vehicle models are being evaluated.
Limited studies on combinations of a. manifold reactor and catalytic converters
have been conducted. General Motors reports that a few experimental systems
show promise of low emissions at levels at or below 1975 standards. These
systems are not ready for production because of problems related to both
subsystems which remain to be solved.
General Motors reports that the primary potential application of the thermal
reactor system is the Vega vehicle. Emission levels obtained with a Vega
equipped with a thermal reactor and EGR were reported to range from 0. 2 to
0. 24 gm/mi HC, 2. 8 to 3. 0 gm/mi CO, and 0. 39 gm/mi NO (see Section 2. 2. 4).
2t
Problems encountered with the General Motors manifold reactor concern
driveability and packaging. The need for extensive insulation to maintain high
oxidizing temperatures (1500 to 2000°F) affects the problem of engine compart-
ment packaging. More experience in the use of high-efficiency insulation
6-5
-------
materials is said to be needed. Air requirements for the thermal reactor
exceed those for the catalytic converter; a larger air pump is therefore
required. Satisfactory materials for manifold reactor durability have not
yet been found.
When questioned on its emission test results with a thermal reactor on a
rotary engine, General Motors was unable to provide any reason why emissions
achieved by Toyo Kogyo were significantly lower (Refs. 6-7, 6-8).
6.2.5 International Harvester
International Harvester is considering the use of a thermal reactor on two
alternate-choice systems for 1975. The first consists of a thermal reactor,
EGR, and advanced fuel system with fast-heat manifold. All development
testing has been carried out on the 5500-lb inertia weight Travelall vehicle.
Representative CVS-CH emission levels for this vehicle were reported to be
(in grams per mile):
HC 0.37 to 1.0
CO 14. 8 to 22. 3
NOx 1.2 to 2.8
Durability testing of this system was conducted to 24, 000 miles , at which time
the reactor was removed for inspection. The left reactor core runners were
found to be eroded and the core assembly severely warped. High underhood
temperatures resulted in ignition wire failures at 20,000 miles. Detailed
emission levels at intermediate mileage points for this vehicle are shown in
Section 2.2.5 (International Harvester alternate-choice systems).
A second vehicle, also durability-tested to approximately 26,OQO^niles (see
Section 2.2.5) with the thermal reactor system, exhibited deterioration in CO
emission control at 25,794 miles (from an initial value of 14.8 gm/mi to a final
6-6
-------
value of 42.3 gm/mi). The reasons for this are currently being investigated.
Intermediate mileage points were not reported. It was concluded by Inter-
national Harvester that the CO control with thermal reactors was inadequate.
Reactor casting life was reported as "unacceptable" (cracking at 2000 to
4000 miles).
Another alternate system, composed of a thermal reactor, catalytic converter,
EGR, air injection, and engine modifications, was tested on the Travelall
vehicle. International Harvester reported "representative" emission levels
of 0.63 gm/mi for HC, 3.5 gm/mi for CO. and 0.77 gm/mi for NO . No
J\.
details regarding test mileage, converter type, or other specific information
were provided (Refs. 6-9, 6-10).
6.2.6 British Leyland
British Leyland's approach has been directed toward the development of a
1975 emission control package which, with the add-on of a reducing catalyst,
would meet the standards for 1976. A thermal reactor was considered but was
rejected when it was concluded from experimental investigations that a thermal
reactor/EGR system would be unable to meet the 1976 NO standards. British
Leyland indicated, however, that thermal reactor work is being pursued in
conjunction with Associated Octel and with Engineering Research and Applica-
tion, Ltd, (Ref. 6-11).
6.2.7 Daimler-Benz
Development effort with thermal reactors, both singly and in conjunction with
oxidation catalysts, was conducted by this manufacturer in three of seven
systems under consideration. However, thermal reactors are not used in its
first-choice or alternate 1975 candidate systems, and no details on thermal
reactors were provided (Ref. 6-12).
6.2.8 Nissan
The Nissan second-choice system uses a thermal reactor in addition to an
HC/CO catalytic converter, EGR, air injection, and engine modifications.
6-7
-------
Reactor deformation and core damage have been encountered frequently.
An inexpensive and easily workable core material possessing a good corrosion
characteristic and high-temperature strength has not been found. An
acceptable insulating material and the proper configuration to retain it intact
has not been developed.
CVS-CH emission levels for the Nissan thermal reactor system were reported at
8000 miles as 0.47, 3.6, and 0.92 gm/mi for HC, CO, and NO , respectively
ji
(see Section 2.2. 13 and Ref. 6-13).
6.2.9 Saab
To date, Saab has tested thermal reactors of the early DuPont-type, the Esso
RAM-type, and a Saab-Scania design.
Saab states that although the emission-reducing potential of the thermal reactor
does not seem to be adequate to meet the 1975 standards, the durability problems
may be easier to solve than with the use of the catalytic converter. Saab,
therefore, is continuing development work in this area as a backup, but is not
planning to combine the thermal reactor with an HC/CO catalytic converter.
A proprietary thermal reactor developed by Saab which shows promise will be
fitted to a fuel injection engine to determine the potential of such a combination.
Emission results reported by Saab for thermal reactor-equippe.d vehicles are
shown in Table 6-1. It should be emphasized that although a total of 12,992
miles was reported by Saab for Test 14, this mileage actually represents
vehicle mileage and not reactor mileage, since the reactor was "stripped
and refurbished" by Zenith Carburetor five times during the reported mileage
period.
6-8
-------
Table 6-1. Saab Thermal Reactor Systems
Test
No.
13
14
15
16
Car
No.
209b
209C
427
22 lb
Reactor
Type
DuPont
DuPont
Esso RAM
Saab -Scania
Reactor
Mileage
0
3400
0
12992
160
0
1500
Emissions, gm/mi
HC CO NOX
0.20 3.6 1.3
0.41 14.56 1.23
0.26 13.27 3.03
0.12 3.24 1.32
0.65 7.82 1.03
Remarks
No EGR. 7% power loss.
Emissions reported unchanged
from 0 mile results.
No EGR. 7% power loss.
Frequent cracking and leak-
age. Plug wires burned.
Test continuing*^.
Best result, optimization
testing. Use of EGR not
specified. Durability test to
be started.
No. EGR, Electr. fuel injection
Not tested, tremendous
cracking and sealing
problems .
a!975 CVS-CH test procedure.
Normal driving cycle.
MAR driving cycle.
Reactor stripped and rebuilt at frequent intervals. Air pump replaced at 12, 992 miles.
-------
Specific problem areas itemized were: (a) failure to achieve reduction of
CO to required levels, (b) thermal expansion (reactor-to-cylinder block),
(c) high fuel economy loss of 10 to 15 percent, (d) power loss up to 10 percent,
(e) overheating of the reactor, and (f) high temperatures in the vicinity of
the reactor (Ref. 6-14).
6.2.10 Toyo Kogyo
Toyo Kogyo is fairly optimistic that the 1975 standards can be met with a
thermal reactor system similar to the design currently installed on their
rotary engines. It plans to establish final production design specifications
for 1975 vehicles in October 1972.
Three vehicles with 70-CID rotary engines have been tested at low mileage
(300-1000 miles). Emission data based on the average of 18 tests on the three
vehicles, using the 1975 Federal test procedure, were 0. 17 gm/mi HC,
2.2 gm/mi CO, and 0.93 gm/mi NO . This is discussed in greater detail in
3C
Section 2.2. 17 as the Toyo Kogyo first-choice system for the 1975 rotary
engine vehicle. General Motors has indicated that its emission test results
with a reactor-equipped rotary engine were significantly higher than those
of Toyo Kogyo.
Because the 1975 reactor will operate at a temperature about 130 F higher
than the 1972 production model, durability of the 1975 reactor must be con-
firmed. The possible adverse effects of the thermal environment on various
underhood components must be determined.
It is anticipated that fuel consumption will increase by about 5 percent over the
1972 models. Fuel with lead concentrations currently on the market is not
considered to pose severe durability problems, although, in general, the lower
lead content fuel is preferred from the durability standpoint.
6-10
-------
With its reciprocating piston engine, Toyo Kogyo is conducting development
work on a thermal reactor system, a catalyst system, and a combination
system of the two. These are discussed in greater detail in Section 2.2. 17
as candidate first-choice systems for Toyo Kogyo.
Recent data on two test vehicles with 110-CID reciprocating piston engines
equipped with thermal reactors and tested between 300 to 1100 miles achieved
average emission levels of 0. 15 gm/mi HC, 2.6 gm/mi CO, and 2.3 gm/mi
NO , based on an average of six tests on the two vehicles.
Use of the thermal reactor is seen as having particularly severe under hood
effects as compared with the rotary engine, because the reciprocating engine
occupies a larger volume in the engine compartment (Refs. 6-15, 6-16).
6.2.11 Toyota
No thermal reactor is envisioned for 1975. A thermal reactor is planned for
installation ahead of an HC/CO catalytic converter for 1976.
Toyota indicated that the thermal reactor performance goals (unspecified)
have nearly been met, but major unresolved problem areas remain, including
poor material durability and heat resistance and the need for further develop-
ment of the secondary air control system to prevent reactor overheating.
Toyota also felt that heat from the thermal reactor may cause vapor lock in
the brake system (Refs. 6-17, 6-18).
6.2.12 Volkswagen
Volkswagen indicates that it has had numerous problems with thermal reactors.
Due to the horizontally opposed cylinder arrangement of the Volkswagen engine,
the system requires two reactors or, alternately, extremely long exhaust port
extensions.
6-11
-------
Volkswagen's recent test results indicate that the 1975 emission standards
cannot be attained with thermal reactors alone. Therefore, the reactors are
being used principally to provide faster warmup of the catalytic converters
used as a component in the Volkswagen emission control systems (Ref. 6-19).
6.2.13 Volvo
Volvo's fourth choice for a 1975 system includes a thermal reactor for HC/CO
control. A turbulent reactor designated as Type 4 (modified) has been selected
for vehicle evaluation and the best (low mileage) results obtained are shown in
Table 6-2.
The problems reported by Volvo for the thermal reactor system are high fuel
penalty (about 50 percent increase in fuel consumption), poor driveability, loss
of performance, and mechanical failures (Ref. 6-20).
6.2.14 DuPont
The DuPont reactor is a conventional cylindrical design consisting of a cast-
iron outer shell which houses a tubular core and shield to reduce heat loss.
The latest design configuration, referred to as the Type VUI reactor, recently
was designed for the V-8 engine and is the same physical size as the older
Type V version but external insulation is used, instead of internal heat shielding,
to maintain high reactor temperatures. The Type V reactor is illustrated in
Figure 6-1.
The DuPont emission control concept comprises the thermal reactor types
described above, along with EGR and a trapping system to remove lead
particulates from the exhaust gas. Recent emission tests of this system
installed in 4- and 8-cylinder engine vehicles were reported in Refs. 6-21
and 6-22. The data, which were based on the 1975 CVS-CH procedure, are
summarized in Table 6-3. It may be seen that the system does not meet the
1975 standards for CO.
6-12
-------
Table 6-2. Volvo Thermal Reactor (VFM 80)
Emission Results
Test
No.
656
721
744
752
1000
Car Reg. No.
OB 48503
Automatic
Transmission
Air /Fuel
Setting
Percent
+ioa
-noa
+ ioa
+ioa
+ 10a
Reactor
Mileage at
Test (Miles)
0
100
140
170
590
Emissions, gm/mi
CO HC NOX
1.92 0.29 2.13
4.09 0.20 1.58
2.61 0.09 1.92
2.09 0.19 2.40
1.58 0.12 1.36
Test
Procedure
Year
1975
CVS-CH
Remarks
Without
EGR
Air pump
ratio
1.26
Air pump
ratio 1. 5
With EGR
aCold start enrichment disconnected at 600°C exhaust temperature from reactor.
Full load enrichment disconnected.
Table 6-3. DuPont Reactor System Emission Results
Engine Type
4-Cylinder(2)
V-8(2>
Emissions, gm/mi
HC CO NOX
0.29 5.2 0.6
0.32 5.2 0.55
0.18 4.7 0.58
0. 18 4.7 0.70
0.20 6.0 0.70
0.18 7.2 0.52
0.22 7.1 0.58
Remarks
Average of DuPont tests
Outside lab - 2-Test Average
EPA Test average
^1975 CVS-CH test procedure.
'unidentified U.S. manufactured cars.
6-13
-------
DuPont states that the V-8 fuel economy was decreased by 14 percent and the
4-cylinder's by 17 percent compared to standard production models when
driven over the road in a mixed city suburban course. Full-throttle per-
formance of the V-8 was not affected relative to the standard production
model; acceleration of the 4-cylinder engine vehicle was impaired by the
necessity of using EGR at full throttle to achieve low NO emissions.
x
With regard to emissions durability, DuPont states that thermal reactors have
been shown to control HC and CO with essentially no change in emission levels
for the life of the vehicle.
The physical durability of systems equippped with the DuPont reactor is a
question that apparently is not yet resolved. A six-vehicle test program con-
ducted by the State of California in 1970 was terminated at 20,000 miles because
of excessive wear of the timing chain and valve train caused by metal oxide
particles from the reactor core being taken through the EGR system into the
lubricating oil.
Based on engine dynamometer tests, DuPont believes that reactor cores
fabricated of Inconel 601 would be more oxidation-resistant than 310 stainless
steel and would operate satisfactorily for the lifetime of the car. However,
DuPont has not yet tested Inconel 601 on vehicles.
It was indicated that damage has been observed in electrical and plastic com-
ponents under the hood due to the heat generated by the thermal reactors
(Refs. 6-21, 6-22).
6.2.15 Esso
The most recent Esso thermal reactor development is referred to as RAM
(Rapid Action Manifold). The reactor (Figure 6-2) consists of a torus made
of Type 310 stainless steel. Connecting arms lead exhaust gases from the
engine to the torus. The gases flow around the torus and exit through a slot
6-14
-------
into a central plenum and then into the exhaust pipe. The slot is positioned
so that the gases must flow at least half-way around the torus before they can
exit, and so that a portion of the circulating gases flows completely around
the torus to mix with the entering engine exhaust. Air is injected into each
engine exhaust port and is aimed toward the valve. Most of the thermal
reaction takes place as the gases swirl through the reactor. Flameholders
are located at the exit of each engine exhaust port; they act to stabilize the
flame at the exhaust port outlets during start-up, when the engine is choked.
Esso results for the RAM system are quoted as follows (Ref. 6-23):
1972-CVS-C Emissions, gm/mi
HC CO NOx
Without EGR 0.07 4.2 1.89
WithEGR(l2%) 0.08 3.7 0.72
These and other Esso tests of the modified RAM concept were intended to
be demonstrative only; no durability tests have been made. If this concept
were tested for durability, a more adaptable material than the Type 310
stainless steel used in the demonstrator model would be required.
6.2.16 Ethyl
The Ethyl Corporation has been actively pursuing the development of lead-
tolerant emission control devices. This effort has evolved a combination of
emission control devices referred to as the Ethyl Lean Reactor System, which
includes a full-size lean thermal reactor for HC and CO control, an EGR
system for NO control, and advanced carburetion for engine'operation at the
selected lean air-fuel ratio (approximately 17.5) provided by a specially
developed, high-velocity carburetor. Spark advance characteristics in the
Ethyl system are tailored to provide the best compromise among fuel economy,
driveability, and low emissions.
6-15
-------
Ethyl has demonstrated this approach with vehicle tests. All test work
reported has been done with fuel containing approximately 3 gm/gal of lead.
With use of this fuel, the Ethyl Lean Reactor System avoids fuel economy
penalties incurred by lowering compression ratio to accommodate low-octane
fuels. Ethyl states that the retention of a high-compression ratio also
makes it possible to operate with satisfactory driveability at leaner mixtures
than otherwise would be the case, and minimizes problems of EGR with respect
to vehicle driveability effects.
The most advanced versions of the Ethyl Lean Reactor System are embodied
in several Pontiacs and one 1971 Plymouth. Emissions of two of these cars,
based on the single-bag CVS test procedure, are shown in Tables 6-4 and 6-5.
Similar data obtained with the CVS-CH test procedure for the 1971 Plymouth
are compared with the single-bag data in Table 6-4. As can be seen, the
HC and CO emissions exceed the 1975 standards. The NO emissions are
well below the 1975 standard.
Further improvements proposed by Ethyl which could reduce HC and CO
emissions include moderation of the amount of air injected during the first few
minutes of warm-up operation to increase exhaust oxidation during the choking
period; design changes to improve heat conservation in the exhaust ports
and exhaust port liners; improvements in the intake manifold to promote .
quicker warm-up; alterations in transmission characteristics to accelerate
warm-up; use of higher compression ratio to permit still leaner mixtures
and better utilization of EGR; and use of charcoal absorber traps to reduce
HC exhausted during engine startup.
These are logical technical approaches, but until they are incorporated and
demonstrated, this concept is considered deficient with regard to meeting the
1975 HC and CO standards (Ref. 6-24).
6-16
-------
Table 6-4. Ethyl Lean Reactor--Emission Data
for 1970 Pontiac (Vehicle 766)
Vehicle Description
1970 Pontiac LeMans
400 CID Engine
Automatic Transmission
Power Steering
Power Brakes
1972 CVS Procedure
Run Date
4-5-71
4-6-71
4-19-71
4-20-71
4-21-71
4-22-71
6-3-71
6-24-71
Avg.
12-18-70
1970 7-Mode Procedure
Run Date
4-8-71
4-13-71
4-14-71
Avg.
Equivalent gm/mi
Modifications
3-Venturi Carburetor
EGR System
Exhaust Manifold Reactor
Exhaust Port Liners
Evaporative Loss Controls
Exhaust Cooler Units
Particulate Trapping Device
Air-Injection Pump (Operates During
Choking Period)
Transmission Modifications
(Modulator and Governor)
HC CO NOx
(gm/mil (gm/mi) (gm/mil
0.74 7.3 .40
0.75 7.0 .60
0.74 5.3 .70
0. 78 6. 2 . 70
0. 84 6.2 . 48
0.82 5.9 .45
0.88 6.5 1.45
0.73 6.8 1.40
0.79 6.4 1.52
0.64 9.1 1.09
HC CO NO
(ppm) (%) (ppm)
19 0.21 226
20. 0.20 200
.23 0.21 197
20.7 0.21 208
0.26 5.0 0.81
Table 6-5. Ethyl Lean Reactor--Emission Data for
'.. 1971 Plymouth (Vehicle 18M-448)
Vehicle Description
1971 Plymouth Fury HI
360 CID Engine
Automatic Transmission
Power Steering
Power Brakes
Air Conditioning
1972 CVS Procedure (Single -bag tests)
HC
Run Date gm/mi
2-26-71 .1.00
3-2-71 0.74
3-8-71 0.92
3-24-71 0.82
4-8-71 1.00
Avg. 0. 89
1975 CVS Procedure (Three-bag tests)
0.52
Modifications
3-Venturi Carburetor
EGR System
Exhaust Manifold Reactor
Exhaust Port Liners
Evaporative Loss Controls
Exhaust Cooler Units
CO
gm/mi
8.0
7.3
7.6
10.0
10.0
8.6
6.2
gm/mi
1.6
1.7
0.86
1.5
1.23.
1.37
1.37
-------
REFERENCES
6-1 Automobile Emissions Control - A Technology Assessment as of
December 1971, Mobile Source Pollution Control Program, Office of
Air Programs, Environmental Protection Agency, 1 January 1972.
6-2 American Motors Corporation, Technical Data Submittal provided by
AMC at the request of the EPA Suspension Request Hearing Panel,
20 April 1972.
j
6-3 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the Clean
Air Act, " March 1972.
6-4 Chrysler Corporation, Technical Data Submittal provided by Chrysler
at the request of the EPA Suspension Request Hearing Panel,
25 April 1972.
6-5 Chrysler Corporation, Transcript of Proceedings -- Auto Emissions
Extension-- Environmental Protection Agency, Washington, D. C. ,
20 April 1972.
6-6 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II, 5 April 1972.
6-7 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
6-8 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
D. C., 26 April 1972 (recall).
6-9 International Harvester, "Request for One-Year Suspension of 1975
HC and CO Light-duty Emission Standards Submitted to EPA, Washington,
D. C., " 29 March 1972.
6-10 International Harvester Company, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
D. C., 14 April 1972.
6-11 British Leyland Motors, Inc. , "EPA Hearing of Volvo Application for
Deferment of Emission Legislation Applicable to 1975 Model Year
Vehicles, " March 1972.
6-12 Daimler-Benz, "Statement of Daimler-Benz AG before the Environmental
Protection Agency, Washington, D. C.," April 1972.
6-19
-------
REFERENCES (continued)
6-13 Nissan Motor Corporation in U.S.A. (Datsun), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental Protection
Agency, Washington, D. C., 11 April 1972.
6-14 Saab-Scania of America, Inc. and Saab-Scania AB, "Information Sub-
mitted in Response to Subpoena dated March 17, 1972 of Environmental
Protection Agency, Washington, D. C. "
6-15 Toyo Kogyo Company, Ltd., "Statement of Toyp Kogyo Company, Ltd., "
April 1972.
6-16 Toyo Kogyo Company, Ltd., Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
D. C., 21 April 1972.
6-17 Toyota Motor Company, Ltd., "A Summary of Toyota's Technology and
Processes for Meeting the 1975 Federal Emission Standards, "
5 April 1972.
6-18 Toyota Motor Company, Ltd., Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
D. C., 13 April 1972.
6-19 Volkswagen of America, Inc., "Information and Documentary Materials
Relating to Volkswagen's Emission Research and Design Effort to Meet
1975 Federal Emission Goals, " 10 April 1972.
6-20 AB Volvo, "Request for Suspension of the 1975 Emission Standards, "
9 March 1972.
6-21 E. I. DuPont De Namours and Company "Statement for Presentation to
the Environmental Protection Agency at a Hearing on the Request by
Volvo, Inc. , for a One-Year Suspension of the 1975 Light-Duty Vehicle
Emission Standards," April 10, 1972.
6-22 E. I. DuPont De Namours and Company, Technical Data Submittal
provided by DuPont at the Request of the EPA Suspension Request Hearing
Panel, 28 April 1972.
6-23 R. J. Lang, "A Well Mixed Thermal Reactor or System for Automotive
Emission Control" SAE Paper No. 710608, June 1971.
6-24 The Ethyl Lean Reactor System, Ethyl Corporation Research
Laboratories, Detroit, 1 July 1971.
6-20
-------
7. SECONDARY AIR SUPPLY
7. 1 SUMMARY DISCUSSION
Although secondary air injection at engine exhaust ports has been widely used
as an independent control device for the suppression of HC and CO emissions
since 1966, it is not being given serious consideration by any automobile
manufacturer as a prime system for meeting 1975 standards.
In aftertreatment devices for HC and CO control, such as catalytic converters
and thermal reactors, sufficient oxygen is needed to promote oxidation of the
pollutants. The oxygen required is provided by an engine-driven air pump.
The production hardware for the current air injection system typically con-
sists of an engine-driven air pump, hoses, steel tubing manifolds to deliver
the air to each exhaust port, and a series of valves to prevent backfiring and
backflowing and to provide relief to the pump when the engine is operating at
high speeds and peak loads. In most systems, the belt-driven air pump pro-
vides air flow modulation solely on the basis of engine RPM and neglects the
demand variation due to throttle setting. A number of manufacturers are
investigating the use of fully modulating electric drives or air by-pass tech-
niques for advanced control systems.
Generally, little more than passing mention of the use and type of air pump
drives was made by the automobile manufacturers in discussing their pro-
jected 1975 emission control systems. Pump durability and pump noise are
frequently identified as problem areas; the durability problem appears to be
particularly troublesome. However, no manufacturer classifies any part of
the air injection system as critical for 1975.
Fuel economy and power-loss penalties associated with the operation of air
injection systems are negligible.
7-1
-------
In the following paragraphs, the absence of an entry for a given manufacturer
indicates that specific information concerning air injection system components
was not provided.
7. 2 SELECTED SYSTEMS, BY MANUFACTURER
7. 2. 1 Chrysler Corporation
The Chrysler system for 1975 includes an oxidation catalytic converter and a
partial thermal reactor (Ref. 7-1). The secondary air is supplied by a
26-cubic-inch-per-revolution air pump. The previously used 19-cubic-inch
pump was required to operate at a speed too high for satisfactory pump life.
A drive ratio of 1. 52:1 has been used in the Chrysler integrated system tests.
7. 2. 2 Ford
Secondary air will be used with Ford's current first-choice system, which
utilizes a catalytic converter (Ref. 7-2). In 1971, Ford conducted high-
mileage tests of six vehicles equipped with 1975-type air injection systems.
Secondary air pump failures occurred in four of these vehicles at mileages
ranging from 5000 to 35,000. However, Ford does not regard the air pump
as a significant problem component.
7. 2. 3 General Motors
General Motors has used a 19-cubic-inch-per-revolution pump extensively in
production vehicles and feels it has demonstrated satisfactory performance
and reliability. All current installations are driven directly by the engine
through a conventional V-belt arrangement. Most applications have a drive
ratio of about 1. 2:1 (Ref. 7-3).
The catalytic converter requires approximately 30 percent more air than is
currently delivered. Use of the 19-cubic-inch pump would require drive
ratios of approximately 2:1. Durability at speeds in excess of 6000 RPM,
which would be needed, is limited. In addition, new noise problems are
introduced at high speeds. The approach considered for 1975 includes a
larger displacement pump with drive ratios which could differ for particular
vehicle applications.
7-2
-------
Air will continue to be introduced near the exhaust ports. The prior experience
of General Motors with its Air Injection Reactor System (AIR) has shown this
to be the optimum location, and experiments with oxidation catalysts have not
established a more desirable location.
7. 2. 4 Volvo
The use of secondary air is contemplated for all four of Volvo's alternate
1975 systems (Ref. 7-4). A program to develop a secondary air supply sys-
tem was initiated in 1970. The system may include a temperature sensor in
the converter or reactor and a valve for shutting off or by-passing the secon-
dary air. The research and development phase is reported to be 80 percent
completed and engineering testing is in the initial stages.
Pump noise and deterioration of air flow control due to wear of valves and
seals, as well as failure of the temperature sensors caused by vibration, are
the main problems in Volvo's air supply system.
7. 2. 5 British Leyland
British Leyland will use air injection systems similar to those installed in
its 1972 model year vehicles. The existing air pump capacity is insufficient
for the 1975 catalytic converter systems, and modified designs are being
investigated (Ref. 7-5).
7. 2. 6 Daimler-Benz
Daimler-Benz1 first-choice system includes an oxidation catalyst, air injec-
tion, and EGR. This manufacturer is having air pump durability problems and
has recently engaged a new supplier who is working to improve durability
(Ref. 7-6).
7. 2. 7 Saab-Scania
Saab-Scania reports that AC-Delco or Lucas rotary vane-type secondary air
supply pumps with V-belt drives are being investigated. Tests have shown
that injection of air as close as possible to the exhaust valves yields the best
results. Engine power and fuel economy losses associated with the pump are
slight (Ref. 7-7).
7-3
-------
REFERENCES
7-1 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the Clean
Air Act, " March 1972.
7-2 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II, 5 April 1972.
7-3 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
7-4 AB Volvo, "Request for Suspension of the 1975 Emission Standards, "
9 March 1972.
7-5 British Leyland Motors, Inc., "EPA Hearing of Volvo Application for
Deferment of Emission Legisl- Uon Applicable to 1975 Model Year
Vehicles, " March 1972.
7-6 Daimler-Benz, "Statement of Daimler-Benz AG before the Environmental
Protection Agency, Washington, D. C. ," April 1972.
7-7 Saab-Scania of America, Inc. and Saab-Scania AB, "Information Sub-
mitted in Response to Subpoena dated March 17, 1972 of Environmental
Protection Agency, Washington, D. C. "
7-4
-------
8. EMISSION GOALS
8. 1 GENERAL
In order to comply with the 1975 emission standards on production vehicles
at 50, 000 miles, the automobile manufacturers must demonstrate substanti-
ally lower emission goals on low-mileage engineering prototype vehicles to
account for a number of parameters affecting emission control system per-
formance. These parameters include the emission deterioration factor (DF)
of the control system, the prototype-to-production slippage factor (PPS), and,
in case emission averaging is not permitted, the production quality control
factor (QCF). Based on these definitions, the low-mileage emission goals
for engineering prototype vehicles are computed from the following equation
,, M , .
Mgoal = DF x PPS x QCF ' gm/mi
where M represents the 1975 HC, CO, and NO emission standards and DF
represents the system deterioration factor between low mileage and 50, 000
miles. To minimize "green" engine/control-system effects, EPA has
selected the 4000-mile point as the low-mileage reference value. It should
be noted that deterioration factors must be used with care. In general,
deterioration factors determined for one type of vehicle/emission control
system are only applicable to similar configurations.
The in-house emission goals established by the various manufacturers for
reciprocating spark ignition engine-powered vehicles are presented in Table
8-1. Also listed in this table are the emission goals selected by Toyo Kogyo
and Daimler-Benz for rotary engine-powered vehicles. Daimler-Benz
8-1
-------
Table 8-1. Low Mileage Emission Goals (Averaging Permitted)
Projected 1975 Control Systems
oo
i
Manufacturer
I. DOMESTIC
American Motors
Chrysler
Ford
General Motors
II. FOREIGN
British Ley land
Daimler-Benz
Mitsubishi
Nissan
Saab-Scania
Toyo Kogyo
Toyota
Volkau-agen
Volvo
Emission
Control Concept
EM + EGR + AI + OC
EM t EGR T AI + OC
EM + EGR + AI * PTR + OC
EM + EGR + AI + PTR+ OC
Catalyst change at 23, 000
miles
°Q. 5% of cars meeting
standards at 50,000 miles
EM * EGR + AI -f(TR) + OC
EM + AI OC
EM t EGR * AI 4 OC
Diesel engine (no catalyst1
Rotary engine 4EGR4AI4OC
EM t AI 4 (TRI * OC
EM * AI 4 TR
EM . AI + EGR 4 OC
EM « AI 4 OC
EM * AI + OC
EM * AI * TR
Rotary engine 4- AI 4- TR
EM t AI t EGR 4 OC
EM 4 (EFK t AI * EGR 4
TR 4- OC
EM 4 AI + EGR * OC
Emission Goals,
gnn/mile
HC CO NOx
0.15 2.55 2.2
0.10 1.50 2.2
Not specified
0.20 1.7 2.07
0.27 2.27 2.07
0.07 0.71 1.16
0. 16 1.36 1. 5
0.20 2.0 2.0
Not specified
0.20 2.0 2.0
0. 14 1.2 1.4
0.26 2.2 2.0
0. 18 1. 50 0. %
0.20 1.7 1.5S
0. 19 1.5 2. 3
0.29 2.3 2.3
0.29 2.3 2.3
0.19 1.5 1.9
0. 17 1.4 0. 12<
0.20 1.7 1.2
Reference
Mileage
4000
<10
-
-
Low
Low
Low
Low
_
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Selected Control
System
Deterioration
Factor
HC CO NOX
2.0 - 1.1
1.1
-
2.0 2.0 1.5
1.5
_
18 18 18
2.0 2.0 1.7
_
_ _
2.0 2.0
-
2.0 2.0 1.4
2.0 2.0 2.0
2.0 2.0 l.Z
1.3 1.3 1.2
1.3 1.3 1.2
2.0 2.0 1.5
_
_
Prototype-To-
Production Slippage
Factor
Remarks
-1.25
1.25
-
-
_
l.Z
-
_
-
-
1. 1
-
1. 1
1. 1
1. 1
1. 1 - 1.2
<1.3
_
Catalyst replacement may be
required
Selection of goals not pnssi-
maintenance)
bility characteristics
Best estimate of goals: lack
of durability data
vehicles
Goals may have to be lowered
further
Will meet 1975 emission
standards
Goals may not be stringent
enough (<0.02 gm/gal Pb)
Preliminary estimate
Toyo Kogyo believes that they
can meet these goals
Preliminary estimates
Catalyst replacement at
20,000 mi1
Preliminary goals: insufficient
data
"1976 NOx GOAL
EM = Engine Modifications TR = Thermal Reactors
EGR = Exhaust Gas Recirculation OC = Oxidation Catalyst
-------
has stated that the 220D diesel vehicle will probably meet the 1975 standards
but did not provide emission goals for diesels. With the exception of one set
of numbers presented by General Motors, the emission goals established by
the automobile manufacturers are based on the emission averaging concept
(QCF = 1. 0). Another set of emission goals presented by General Motors is
listed in Table 8-1. This set is based on the assumption that 99. 5 percent of
the production vehicles meet the 1975 standards at 50, 000 miles. This
assumption results in such extremely low HC and CO emission levels that it
is doubtful whether these values can be attained with current spark ignition
engine emission control system technology.
Most manufacturers have assumed HC and CO emission deterioration factors
of 2. 0 for systems incorporating catalytic converters. Based on the avail-
able test data, this assumption appears too optimistic, although further
improvements in the carburetion, choke, and ignition systems, and in catalyst
performance might be achieved in time for use in 1975 vehicles. Toyo Kogyo
has selected a HC and a CO deterioration factor of 1. 3 for systems incor-
porating a thermal reactor only. This is a lower factor than that selected for
its systems incorporating a catalytic converter.
NO deterioration factors assumed by the manufacturers vary between 1. 1
3C
and 1. 8. It is believed that these levels are attainable, although EGR system
maintenance may be required to accomplish this.
The emission goals presented by the automobile manufacturers are based on
the ground rule that catalyst replacement is not permitted during the 50, 000-
mile test. If catalyst replacement were permitted at intermediate mileage
points, the emission goals could be relaxed somewhat. The degree of relax-
ation is primarily determined by the shape of the emission-versus-mileage
curve which is generally different for different vehicle/control system com-
binations. General Motors is the only manufacturer that has provided emission
goals for 25, 000-mile catalyst replacement intervals.
8-3
-------
8.2 DETERIORATION FACTOR
The deterioration factor (DF) of the emission control system is primarily
responsible for the manufacturer's stringent emission goals. This factor
accounts for the emission increase which results from the performance
degradation -with mileage accumulation of all components utilized in the
system including the engine, and the catalyst and other aftertreatment
devices. In general, the catalytic converter is the critical component. As
discussed in Section 5.5, catalyst degradation is the result of poisoning of
the active elements by lead, phosphorus, sulfur, and oil additives, and of
attrition and exposure to overtemperature conditions. Those manufacturers
considering thermal reactor systems expect their deterioration factors to be
lower than those of catalyst systems.
Many of the high mileage tests of emit-.ion control systems incorporating a
catalyst indicate a rather gradual deterioration of emission performance with
mileage accumulation. This is illustrated by the HC and CO data provided by
American Motors, General Motors, Engelhard, and Ford and by the HC data
presented by Matthey Bishop. These data suggest that deterioration factors
derived for a particular vehicle/control system are only valid for similar
configurations and operating conditions. For example, the deterioration
factors derived from a catalyst system operated under idealized conditions
(lead-sterile fuel and moderate catalyst temperature) are not necessarily
applicable to similar vehicles which are subjected to commercially available
"lead-free" fuel and/or more severe durability or customer driving patterns.
Test data provided by Ford from the 1974 California catalyst-only vehicle
fleet indicate rapid degradation of the emissions during the fir-st few thousand
miles on two of the five vehicles. In both instances the emissions remained
essentially constant from this mileage point up to 50,000 miles. This trend
is contradictory to other Ford durability data.
8-4
-------
The deterioration factors derived from the high mileage emission data
provided by the automobile manufacturers are summarized in Figure 8-1.
Although it is not possible to precisely correlate these data, it is apparent
that the degradation has generally been more severe for systems with low
initial (low mileage) emissions.
Since the emission control systems projected for use in 1975 vehicles will
incorporate improved carburetion, choke, and ignition systems as well as
improved (stabilized) catalytic converters, the emissions and the deterior-
ation factors of these systems should be lower than currently indicated. It
appears that this assumption was included in the considerations made by the
automobile manufacturers in establishing their deterioration factors.
8.3 PRQTOTYPE-TO-PRODUCTION SLIPPAGE FACTOR
The prototype to production slippage factor (PPS) is defined as the ratio of
the average emissions of production vehicles compared with the emissions
of identical engineering prototype vehicles. Based on past experience, the
emissions from production vehicles are, on the average, higher than those of
the prototype because of production tolerances and adjustments made in the
final design and fabrication of certain components. Although these factors
are known for current vehicles, it is difficult to make accurate predictions
for future designs. As indicated in Table 8-1, most manufacturers project
PPS factors between 1. 1 and 1. 25.
8.4 PRODUCTION QUALITY CONTROL FACTOR
The production quality control factor (QCF) accounts for the differences
between the average emissions of a certain vehicle model and the maximum
emissions of a specified percentage of the total vehicle population of that
model. The effect of the QCF on the emission goals is illustrated in
Figure 8-2, which shows the HC and CO emission distributions from 1971
General Motors production vehicles. Although these curves may not be
8-5
-------
210 2
I
I I I I I I
AMC (CVS-CH) A MITSUBISHI (CVS-CH)
O CMC (CVS-CH, est) V NISSAN (CVS-C)
D FORD (CVS-C) O MATTHEY BISHOP (CVS-CH)
0 IH (CVS-CH) G HOUDRY (CVS-C)
O
n v
O
A O O
8
E 3
I" 2
O
D
o
246 8 10 12
CO EMISSIONS AT 4000 mi, gm/mi
0.2 0.4 0.6 0.6 1.0 1.2 1.4
HC EMISSIONS AT 4000 mi, gm/mi
14
Figure 8-1. Deterioration Factors vs Emissions at 4000 Miles
8-6
-------
4.0
3.0
HC EMISSION LEVEL
(GRAMS PER MILE)
2.2
2.0
1.3
1.0
CO EMISSION LEVEL
(GRAMS PER MILE]
LIMIT
95% OF CARS
TESTED ARE
BELOW LIMIT
5% OF CARS
TESTED
0 10 20 30 40 50 60 70 80
PERCENT OF CARS TESTED
90 100
;-/:::'>:88%OFCARS
:
-------
applicable to 1975 model vehicles, they are presented to show trends. As
indicated, extremely low emission goals would be required if a high percen-
tage of the vehicles would have to meet the standards. For example, QCF's
of approximately 2.8 for HC and 3, 1 for CO would be required to achieve
compliance -with 99.5 percent of General Motors vehicles in Figure 8.2. This
results in correspondly tighter emission goals. Conversely, if the emission
averaging concept is adopted, the QCF has no effect on the emission goals
(QCF = 1.0).
8.5 SELECTED PROTOTYPE EMISSION GOALS
8. 5. 1 American Motors
The following prototype emission goals have been established by American
Motors for its 1975 first-choice system, which consists of engine modifi-
cations, oxidation catalysts, and EGR (Ref. 8-1).
Reference Mileage 1975 CVS-CH Emissions, gm/mi
HC
0. 15
0. 1
CO
1.35
- -
NOX
2.2
2.2
4000
Less than 10
These numbers are based on the use of 4000-mile to 50, 000-mile emission
deterioration factors of 2. 0 for HC and CO and 1. 1 for NO , and a prototype-
to-production slippage factor of 1.25. Since the HC and CO deterioration
factors demonstrated by American Motors to date are significantly higher,
catalyst replacement maybe required during the 50, 000-mile period. Ameri-
can Motors forsees no difficulty in meeting the NO standard over the 50, 000-
jC
mile range without EGR maintenance. Substantially lower HC and CO emission
goals were selected for "zero mileage" vehicles to account for "green system"
effects.
8-8
-------
Emission control system durability data from two American Motors Hornet
vehicles (Vehicles DOO-24 and DOO-25) equipped with an Engelhard PTX-423
catalyst and operated on fuel containing 0. 016 gm/gal lead and less than
0.005 gm/gal phosphorus are presented in Figures 8-3 through 8-8. As
indicated in these figures, the emission deterioration is approximately
linear with mileage accumulation. The deterioration factors derived from
these data are shown below. For Vehicle DOO-25, the factors are based on
a linear extrapolation of the data from 24, 000 to 50,000 miles.
Vehicle DOO-24 Vehicle DOO-25
DF
HC
CO
NOX
Miles
0-4000
-
1.95
1.13
Miles
4000-50,000
2. 72
2.41
2. 38
Miles Miles
0-4000 4000-50,000
3.66
1.27 3.20
1.0 1.00
The HC and NO emissions of Vehicle DOO-24 were within the standard at
x
50, 000 miles, while the CO standard was exceeded at approximately 30, 000
miles. As indicated by Engelhard (Ref. 8-2), the CO emissions on that
vehicle should be reduced with use of a 1975-type advanced carburetor.
Although the 4000-50, 000 mile deterioration factors for HC and CO Vehicle
DOO-25 are only slightly higher than those of Vehicle DOO-24, the standards
are exceeded at very low mileage. This illustrates that the system specific
deterioration factor must be coupled with the system specific low mileage
emissions when projecting emission control system performance to high
mileage.
The lead and phosphorus levels of the fuel used in these tests were of the
order of 50 percent of those allowed by the proposed EPA fuel additive regu-
lations. Since fuel contaminants affect catalyst durability, the emission
deterioration factors computed from the American Motors data may be
8-9
-------
O.I
£
M
8 o.e
I I I
ENOW Ett cio NO vie. SPARK ADVANCE
TRAHSMStlON - AUTOMATIC
BOOT - HORNET
CATALTST KMOCLHAJID IMM« n«M| PTX-423
rUIL - UNLEADED (O.OM Bn/rH. PHD). 1.««
CORRELATION RATIO WAS DETERMNED AT THE
SO. 000 mil. POINT USINO DATA FROM VEHICLE
DOO-M. THIS RATIO WAS THEN APPLIED TO ALL
OTHER POINTS OF ACTUAL DATA GATHERED USNC
THE \m PROCEDURE. THE POINTS PLOTTED OH
TMS PACE REFLECT THE USE OF THE RATIO
20. 000 90,000
OISTAKU, III
CO
e'
'
ENGINE - 232 CID HO VAC. SPARK ADVANCE
CAHB. IV
TRANSMISSION - AUTOMATIC
MOT - HORNET
CATALTST - ENOELHARD l~»l« TOOI) PTX-421
FUEL - UNLEAKD 0.016 >n/gQl). PHOS. (<0, 005)
TEST PROCEDURE IIVT9 voluM cakuloM from
CO..EL.TK* .A
CHEULUMINESCENCE EOUVALENT
CORRELATION RATIO WAS DETERUMEO AT THE
VI030 mill POINT USING DATA FIOU VEHICLE
000-24. THIS RATIO WAS THEN APPLIED TO ALL
OTHER POINTS OF ACTUAL DATA GATHERED USIKC
THE Kn PROCEDURE. THE POINTS PLOTTED ON
TMS PACE REFLECT THE USE OF THE RATIO
NO
x
20,000 30.000
DISTAMI. ai
Figures 8-3, 8-4, 8-5. American Motors Durability Test Data--Vehicle DOO-24
8-10
-------
.
FUCL UNLCAOCO '0.916 «miT>lf4|
T*JT ownceoijBr i«»s
E MISSIONS
HC
e MCI we 23? -n
CA»B. IV
TRANSUIUtON AIJTOM*
GOT HO*MEr
C»r«Lf*T . CMGCLHAMD
FUCL tJNlfAOC9 10.0'6
PHfM ((» »wn (1.008).
TEST - P4nCCOtJ« I9T1
J _ , ,i_
», mo in wm
OISTMCI- *!
CO
.-..J
w. ono
tifnuA rJNLEADCD '0. 116 pr*/*ali. »**OS
TfST PttOCEDUDC t»^
OCT **CTON O.M ibv vtrionlatlan)
in. oao «. aon sa aoo
Figures 8-6, 8-7, 8-8. American Motors Durability Test Data--Vehicle DOO-25
8-11
-------
optimistic. Conversely, incorporation of "second-generation" improved
catalysts may actually result in a reduction of the deterioration factors. At
this time there is insufficient information available for a meaningful assess-
ment of these parameters.
It should be noted that Vehicle DOO-24 was tested in accordance with the
1972 Federal test procedure. The data was then adjusted by American Motors
by a factor which was determined from 1972 and 1975 test procedure data
taken at the 50, 000-mile point. This approach is considered an approximation
only.
The emission goals selected by American Motors include a factor of 1. 25 to
account for prototype-to-production slippage. Although current test data
indicate slippage factors of 1. 3 to 1. 3T, American Motors expects by 1975 to
approach the value of 1. 25 through use of improved production, inspection,
and calibration procedures. Test-to-test variability considerations -were
neglected and the concept of emission averaging was assumed for new vehicles
and for vehicles in the field.
8.5.2 Chrysler
The engineering goal of the Chrysler Corporation for 1975 emission control
is to develop a system which will achieve the emission standards through
50, 000 miles of normal operation while at the same time exhibit safe, accept-
able driving characteristics. Chrysler recognizes that emission control
systems suffer deterioration as mileage is accumulated. In past model years,
the emission deterioration at 50C000 miles has been of the order of 33 percent
(Ref. 8-3). However, these factors are not applicable to 1975-type emission
control systems utilizing catalysts with currently unknown durability and
deterioration characteristics.
Chrysler states that several questions have to be answered by EPA before
meaningful emission goals can be established which will ensure that mass-
produced vehicles will meet the 1975 emission standards for their useful
8-12
-------
life. These questions are related to emission averaging procedures, vehicle/
emission control system maintenance, and assembly line testing (Ref. 8-3).
In addition, catalyst operating temperature and fuel contaminant levels,
inciting load, sulfur, and phosphorus, affect emission control system :.
durability to a degree that cannot be determined by Chrysler at this time ;
(Ref. 8-4).
Chrysler provided high mileage emission test data from Cars 333 and 698.
Both vehicles incorporated Engelhard PTX catalysts, and were operated with
fuel containing 0. C2-0.03 gm/gal lead. Car 333 was operated under controlled
conditions, with the maximum catalyst temperature limited to 1500 F. Fre-
quent tuneups were made for the purpose of establishing the potential of
catalytic control systems under "mild" operating conditions. Since higher
catalyst temperatures may be reached in customer vehicles, this test is not
considered representative by Chrysler with respect to the performance and
safety characteristics of its projected 1975 control system.
The HC and CO emissions from Car 333 (1972 CVS-C procedure) arc pre-
sented in Figures 8-9 and 8-10. As indicated, the data are rather erratic but
the emissions are encouraging and the average deterioration factors are low.
Similar results were obtained from Car 698.
8. 5. 3 Ford Motor Company
In their application for suspension (Ref. 8-5), Ford states that current
uncertainty in the deterioration factors of 1975-type vehicles precludes at
this time the establishment of meaningful emission goals. Initially, Ford's
engineering objectives for its principal ("kitchen sink") 1975 control system
were based on the optimistic belief that the average emission levels would
increase by no more than 100 percent for HC and CO and 40 percent for NO ,
from zero to 50,000 miles (Ref. 8-5). In addition, Ford assumed a factor of
1. 1 to account for production slippage between development and certification
vehicles. Although based on very preliminary projections rather than actual
8-13
-------
1 0
'i
"^0.8
E "
ba
C/»
z
0 0 6
C/>
V)
X
UJ
o 0.4C
a:
09
0
I I, I
CAR 333 (360 CIO engine)
TWIN ENGELHARD TOEBOARD CONVERTERS
1972 TEST PROCEDURE
MILD DURABILITY CYCLE
0NEW AIR
UPUMP
0 n
O
> n
-o 0 8 o
0
|
-.LOOSE IDLE
° SCREW
O
°1_
^~ NEW CHOKE
0 SPRING
10,000
20, 000 30, 000
TEST MILES
40, 000
50, 000
Figure 8-9. Chrysler Durability Test Data (HC Emissions)
12
10
E
at
CAR 333 (360 CID engine)
TWIN ENGELHARD TOEBOARD CONVERTERS
1972 TEST PROCEDURE
MiLD DURABILITY CYCLE
O
0NEW AIR
UPUMP
.LOOSE IDLE
'SCREW
Poo
.NEW CHOKE
'SPRING
10,000
20,000
30,000
40,000
50, 000
TEST MILES
Figure 8-10. Chrysler Durability Test Data (CO Emissions)
8-14
-------
test experience with the 1975 system, these objectives provided an initial
target for Ford's development and engineering programs.
Based on further experimental work on six combined thermal reactor/catalyst
vehicles, the average emission deterioration factors projected by Ford for
these systems are 2. 2 for HC, 1. 8 for CO, and 1. 1 for NO between zero
and 4000 miles, and 1.8, 2.0, and 1.3, respectively, between 4000 and
50, 000 miles. The emission data from two of these vehicles are presented
in Figs. 8-11 through 8-14. Considering test data variabilities, there
seems little justification for using different deterioration rates for the low
and high mileage regimes. The data from the remaining vehicles show similar
trends. In all cases the 1975 HC and CO standards were exceeded at low
mileage. The NO emissions were always below the 1975 standard. Ford
3C
attributes the rapid performance deterioration to component failures and mal-
adjustments, as well as catalyst degradation.
Deterioration factors derived from these data by linear extrapolation are as
follows:
Vehicle 12 A 90 Vehicle 17 A 54
DF
HC
CO
NO
Miles
0-4000
2.1
1.69
1.57
Miles
4000-50,000
2.21
4.9
2. 28
Miles Miles
0-4000 4000-50,000
2.41 2.86
1.20 2.80
1.28 1.55
X.
Additional high mileage test data were provided by Ford from the 1974 Calif-
ornia catalyst-only vehicle fleet which was designed to meet the less stringent
1974 California emission standards. As discussed in Section 9, the deterior-
ation factors derived from these data were used to establish the interim
8-15
-------
1971 400-2V FORD 12A90
PTX 5. 35 CONVERTERS-REACTORS-EGR
HYDROCARBON
CARBON MONOXIDE
NEW
CONVERTERS
v>
u)
^ 100
. 80
60
"» 40
o
NEW " 20
CONVERTERS
j- NEW
ff CONVERTERS
RT. CONVERTER
FAILED
1 30
20
EMISSIONS
I
rNEW _
\CONVERTERS
V.
JE
fit
10 52
10 20 30
TEST MILES, 000
40
10 20 30
TEST MILES, 000
40
40
I I I I
OXIDES OF NITROGEN
0 10 20 30 40 SO
TEST MILES, 000
Figures 8-11, 8-12. Ford AMA Durability Test Data (1975 System)
8-16
-------
1971-351-W FORD 1TAS4
PTX-5. 35 CONVERTERS-REACTORS-EGR
HYDROCARBON
CARBON MONOXIDE
100
280
O" "^EFFICIENCY
\ EFFICIENCY
\
REACTOR
FAILED
-I 30
20
EMISSIONS
NEW
REACTOR
fOR-J
I I
10 52
10 20 30
TEST MILES, 000
10 20 30 40 50
TEST MILES, 000
T i i r
OXIDES OF NITROGEN
10 20 30 40
TEST MILES, 000
SO
Figures 8-13, 8-14. Ford AM A Durability Test Data
8-17
-------
standards proposed by Ford for 1975. The HC and CO emissions from two
of these vehicles are presented in Figures 8-15 and 8-16. As indicated in
Figure 8-15, the HC and CO emissions increase very rapidly during the first
2000 miles and remain essentially constant to 50, 000 miles. Data from three
other vehicles in this fleet show similar trends. However, on one of these
three vehicles only 7-mode data were provided by Ford for the low mileage
region and leaded fuel was used on one of these vehicles between 12, 000 and
14,000 miles. Conversely, the data in Fig. 8-16 show a more gradual
degradation.
Ford is in the process of developing additional data from several potential
emission control systems. Although low mileage data from the Ford River-
side test program indicate a reduced rate of deterioration for the first 4000
miles. Ford is not revising its i-mis^on goals on the basis of this preliminary
information. The average zero-to-4000-mile HC, CO, and NO deterioration
X.
factors of the Riverside Group I vehicles are 1. 18, 1.45, and 1. 14, respec-
tively. Over the same interval, the average catalyst deterioration factors are
1.67 for HC and 1. 25 for CO, indicating "green engine" effects and/or measure-
ment variabilities. These values are considerably lower than those from
the catalyst-only and thermal reactor/catalyst vehicle fleets discussed above,
and Ford is very encouraged by these results. Similar results were obtained
from the Group II and Group III vehicles. The average zero to 4000-mile
deterioration factors computed from the Dearborn fleet are comparable to
the Riverside fleet data, although the CO levels are generally higher and the
NO levels somewhat lower for the Dearborn fleet.
Jf
Another important subject related to establishing emission goals is the
ability to accurately measure emissions at the low 1975 levels. Although
considerable progress has been made in the past few years, a number of
testing problems remain unresolved which have a significant impact upon
selection of and compliance with realistic emission goals. These problems
concern data variability, correlation, instrumentation, and vehicle operation.
8-18
-------
1971 351-C 2V COUGAR 1W10
PTX-5.35 CONVERTERS-EGR
HYDROCARBON
CARBON MONOXIDE
NEW CONVERTERS
oo
i
h'
sD
E
E"
CO
CO
. O
NEW CONVERTERS
EFFICIENCY
20 30 40
TEST MILES, 000
20 30 40
TEST MILES, 000
E
E^
M
co~
CO
CO
Figure 8-15. Ford AMA Durability Test Data
-------
1971 351W-2V FORD - 17A53O
PTX 5.1 CONVERTERS - NO REACTORS - EGR (Phase III)
HYDROCARBON
CARBON MONOXIDE
00
I
10 20 30
TEST MILES, 000
10 20 30 40
TEST MILES, 000
I 30
E
M
00
09
09
Figure 8-16. Ford AMA Durability Test Data
-------
The effect of these emission testing-related problems on the emission goals
is illustrated in the following table:
HC CO NOX
Standard - gm/mi 0.41 3.4 0.4
Typical Allowance for 42.7 55.9 37.8
Variability - %
Correlation Allowance -% 15.0 15.0 15.0
Total Uncertainty in % 57.7 70.9 52.8
Total Uncertainty in gm/mi 0.24 2.4 0.21
Required Objective* 0. 17 1. 0 0. 19
Does not include system deterioration
The net effect is the equivalent of a 50-to-70-percent reduction in the 1975
emission standards due to emissions testing variabilities. By comparison,
as discussed in Section 9, Ford used a factor of only 1.2 in computing its
proposed interim standards. Ford believes that this factor can be achieved'
through improvements in test equipment, instrumentation, testing techniques,
and emission averaging.
8.5.4 General Motors
General Motors states that it currently is not in a position to establish
accurate engineering emission goals for 1975 model vehicles because of a
lack of reliable control system deterioration factors and uncertainty whether
emissions averaging and/or catalyst change at intermediate mileage points
will be allowed by EpA. In addition, it feels that the questions of fuel con-
taminant levels, and vehicle recall and warranty must be fully resolved
(Ref. 8-6).
8-21
-------
As indicated by the General Motors 1972 certification data, the performance
degradation of the 1975 emission control systems was rather mild. For
instance, the 4000- to 50,000-mile deterioration factor for HC was only 1. 13.
However, on current systems incorporating catalytic converters and EGR the
deterioration factors observed are substantially higher. Based on the limited
data available to date, General Motors has selected deterioration factors of
2.0 for HC and CO and 1.5 for NO as the most optimistic estimate for 1975-
5C
type systems. This does not include an allowance for potential problems
resulting from short-trip driving. It should be noted that the selected HC
and CO deterioration factors have not yet been achieved by General Motors
on any system approaching the 1975 emission levels.
Based on the selected deterioration factors, General Motors has established
the following emission goals for 1975 systems:
Catalyst Change
No Catalyst Change at 25, OOP Miles
Emission
Averaging
Emissions,
gm/mi
HC
CO
NO
Emission
Averaging
0.2
1.7
2. 07
99. 5% of Cars
Meeting Standards
0.07
0.71
1. 16
X
0. 27
2.27
2. 07
The first and third columns in the above table show the emission levels that
must be achieved in low mileage experimental cars if the average car is to
meet the standards for 50,000 miles. For comparison, the second column
shows the low mileage targets if 99. 5 percent of the individual cars are to
meet those values at 50, 000 miles. In this case, the emission goals for HC
and CO are less than 40 percent of the values computed on the basis of
emission averaging.
8-22
-------
At the request of the EPA Suspension Hearing Panel, General Motors has
provided AMA durability test data from two vehicles operated with base metal
catalytic converters for more than 30, 000 miles and tested in accordance
with the 1975 test procedure. These data, which are presented in Figures
8-17 through 8-19, indicate almost linear HC and CO emission deterioration
with mileage accumulation and somewhat erratic NO emission distributions.
3C
Also presented in these figures are test data from Car 61319, utilizing an -
Engelhard PTX-4 catalyst. Although the emissions appear to level off on
Car 61319 after 5000 to 10, 000 miles, the data sample is inadequate to draw
meaningful conclusions with respect to emission deterioration.
The following deterioration factors were established from Figures 8-17 to
8-19:
Car 933 Car 2233
DF
HC
CO
NOX
Miles
0-4000
1.3
1.45
1. 00
Miles
4000-50,000
3.54
4. 11
0. 96*
Miles Miles
0-4000 4000-50,000
1.16 2.56
1.18 2.50
'very erratic data
As indicated, the 4000- to 50,000-mile deterioration factors of Car 2233 are
significantly lower than those of Car 933, but the emissions on that car are .
higher. This illustrates again that the deterioration factor alone is not a meaning-
ful criterion for evaluating performance of emission control systems.
t
High mileage data from vehicles operated at constant speed (50 mph) were pro-
vided by the AC Spark Plug Division of General Motors. The data from two
of these vehicles are depicted in Figures 8-20 and 8-21 (1975 CVS-CH test pro-
cedure). Again, the emissions increase approximately linearly as mileage is
8-23
-------
1.2
t.O
. 0.8
I I I
+ CAR 2233, OLDS 455, APCC - CATALYST
-O CAR 933, BUICK 455, UOP PZ-4-2I4-R-14 CATALYST
A CAR 61319, CHEV 350, ENGELHARD PTX-4
1975 TEST PROCEDURE
0.2
10,000
CAR 2233
CAR 933
20,000 30,000
TEST MILES
I
40,000
A -
50,000
EMISSIONS
HC
10.000
a CAR 2233, OLDS 455, APCC
A CAR 933. BUICK 455, UOP PZ-4-214-R-14
+ CAR 61319, CHEV 350. ENGELHARD PTX-4
1975 TEST PROCEDURE
20.000 30.000
TEST MILES
40.000
50.000
CO
3.0
2.5
_ I t
E
.- 2.0
,L
0 [
DCAR 2233, OLDS 455, APCC
ACAR 933, BUICK 455, NDP PZ-4
+ CAR 61319. CHEV 350, ENGELHARD PTX-4
10,000
20, 000 30,000
TEST MILES
40,000
50,000
NO
x
Figures 8-17, 8-18, 8-19. General Motors Test Data
8-24
-------
E
M
tn
1.2
i.o
0.8
0.6
0.4
0.2
+ TEST No. 636 OPC 932
O TEST NO. 638 DPC 933
50-mph TIRE TESTS
1975 EMISSION TEST PROCEDURE
TEST No. 638-
OPC 933
TEST No. 638
OPG 932
10,000 20,000 30,000
TEST MILES
40,000
50,000
Figure 8-20. General Motors (AC Division) Durability Test
Data (HC Emissions)
12
10
O TEST No. 638 OPO 933
50-mph TIRE TEST
1975 EMISSION TEST PROCEDURE
10,000
20,000 30,000
TEST MILES
40,000
50,000
Figure 8-21. General Motors (AC Division) Durability Test
Data (CO Emissions)
8-25
-------
accumulated, except for CO on Car 638 DPG 932 which decreases from
18.4 gm/mi at zero mile to 4. 73 at 50, 000 miles. While this CO change
phenomenon was not explained by AC it may have resulted from faulty choke
operation. Since these data are from constant-speed tests, no efforts were
made to derive deterioration factors. The data are presented primarily to
illustrate that substantial system deterioration can occur even under mild
operating conditions.
The high mileage data from AC Spark Plug Test 472 are not considered here
because of uncertainties with respect to the test procedure. According to
General Motors (Ref. 8-7), these data are based on the 7-mode test procedure,
but this is not evident from the test log sheet.
As requested by the EPA Suspension Request Hearing Panel, General Motors
has provided emission data at 4000 miles and 50,000 miles from 11 additional
vehicles equipped with either noble or base metal bulk catalysts (Ref. 8-8).
Many of these vehicles have high emissions initially (under 4000 miles). The
deterioration factors computed from those data are included in Fig. 8-1.
8. 5. 5 International Harvester
The emission goals (in grams per mile) established by International Harvester
for low mileage certification vehicles using catalysts are:
HC = 0. 2
CO =1.7
N0x = 1.5
These values are based on assumed deterioration factors of 1. 2 for the
engines and 1. 5 for the catalyst, and a factor of approximately 1. 1 to account
for production variations, with the assumption that the averaging concept will
be permitted for production vehicle emissions (Ref. 8-9). Furthermore,
periodic catalyst replacement is being considered by International Harvester
to meet the selected catalyst deterioration factor of 1.5.
8-26
-------
International Harvester has provided limited AMA durability data from
Travelall vehicles equipped with base metal catalysts and operated on com-
mercially available "unleaded" fuel. In all cases, the emissions at low
mileage were approaching or exceeding the 1975 standards. The data from
Vehicle 2, which was tested in accordance with the 1975 test procedure, are
shown in Figure 8-22. The emission deterioration on this vehicle is approxi-
mately linear with mileage. If these data are extrapolated, the following
deterioration factors are obtained:
Miles Miles
0-4000 4000-50,000
1.18 2.90
1.35 3.93
Excessive data scatter
8.5.6 British Leyland
The 1972 emission goals (in grams per mile) for low mileage engineering
prototypes are:
HC = 0.16
CO = 1.36
NO = 1.50
Ji
These values are based on an assumed system deterioration factor of 2. 0,
a 20-percent allowance to account for production variations, and on the
assumption that emission averaging will be allowed for production vehicles
(Ref. 8-10). However, test data provided by British Leyland indicate that
the emission deterioration of current systems is significantly higher. For
example, the HC and CO emissions obtained from an Austin Marina vehicle
8-27
-------
TRAVELALL VEHICLE No. 2
AC DELCO BASE METAL CONVERTER
1975 TEST PROCEDURE
0.2
E
^
o
HYDROCARBON EMISSIONS
CARBON MONOXIDE EMISSIONS
,000 20, 000
TEST MILEAGE, mi
Figure 8-22. International Harvester Emission Data
8-28
-------
equipped with an Engelhard stacked PTX catalyst are 0. 11 gm/rrii and 1. 78
gm/mi, respectively, at zero mile, and 0. 63 gm/mi and 4. 65 gm/mi at
17, 000 miles. The NO emissions decreased during that period from 1. 86
gm/mi to 1. 32 gm/mi. Although the data sample is too limited to draw firm
conclusions, the HC and CO emission deterioration in the range tested
increases gradually with mileage accumulation. In the past the prototype-
to-production slippage factor on British Leyland vehicles has varied between
1.0 and 1.25. However, these slippage factors may not be applicable to the
catalytic systems projected for use in 1975.
8. 5. 7 Daimler -Benz
The low mileage prototype emission goals (in grams per mile) established by
Daimler-Benz for both reciprocating and rotary spark ignition engines are:
HC = 0.20
CO = 2.0
NO = 2.0
x
These values include assumed allowances for catalyst deterioration, prototype-
to-production slippage, and measurement inaccuracies (Ref. 8-11). Con-
sidering the test data presented by Daimler-Benz, these goals appear rather
optimistic.
t
Low mileage goals for diesel-powered vehicles were not specified. However,
according to Daimler-Benz the 220D vehicles will probably meet the 1975
standards for HC, CO, and NO .
ji
8.5.8 Mitsubishi
Although the extent of additional catalyst improvements cannot be predicted
by Mitsubishi at this time, it considers the following emission goals (in grams
per mile) to be reasonable estimates for 1975 catalytic and thermal reactor *
systems (Ref. 8-12).
8-29
-------
Catalyst Thermal Reactor
HC 0. 14 0. 26
CO 1.2 2.2
NO ' 1.4 2. 0
.X
The values for the catalyst system are based on assumed HC and CO deter-
ioration factors of 2. 0 and a production quality control factor of 1. 5 to account
for production variations. If emissions averaging is permitted, the QCF
factor becomes unity and the emission goals will be relaxed accordingly.
Based on data provided by Mitsubishi from an unidentified vehicle tested with
an Engelhard PTX-5 catalyst and unleaded fuel, the following deterioration
factors were derived.
Miles Miles
DF 0-4000 4000-50,000
HC 1.60 1.37
CO 1.33 1.88
NO data were not presented by Mitsubishi. Over the range of data shown
3C
(zero to 29, 000 miles), CO emissions increase gradually with mileage while
HC increases rapidly in the first 2000 miles and very slowly thereafter. More
rapid emission degradation was observed with a pelletized catalyst. In all
cases, the emission standards were exceeded at very low mileage.
8.5.9 Nissan
In an effort to meet the 1975 emission standards, Nissan has established the
following emission goals (in grams per mile) for engineering prototype
vehicles (Ref. 8-13).
8-30
-------
HC = 0. 18
CO =1.50
NO = 0. 96
X.
These goals are based on unleaded gasoline (less than 0. 02 gm/gal Pb) and
utilization of the emission averaging concept. The selected NO goal is
sufficiently low to satisfy both the 1975 Federal and proposed California
emission standards.
Deterioration factors of 2. 0 for HC and CO and 1.4 for NO were assumed,
Jt
and a prototype-to-production slippage factor of 1. 1 was used for ail pollutants.
The slippage factor was derived from 1971 and 1972 model year data. Deter-
ioration factors derived from Nissan 1971 and 1972 certification vehicles
are approximately 1. 15 for HC and CO and 1. 0 for NO . Although these
.X
factors are not directly applicable to 1975 vehicles, they provide an indication
of the engine contribution to the deterioration over 50, 000 miles.
As illustrated in Figure 8-23, the data obtained by Nissan indicate substan-
tially higher HC emission degradation. The following deterioration factors
are obtained by linear extrapolation of these data:
Vehicle B-263 Vehicle B-415
DF
HC
CO
Miles
0-4000
1. 18
1.09
Miles
4000-50,000
2.85
1.90
Miles Miles
0-4000 4000-50,000
1.82 2.53
1.10 2.08
8. 5. 10 Saab
In preparing for the 1975 Federal emission standards, Saab-Scania has
established emission goals for low mileage prototype vehicles of 50 percent
or less of the 1975 standards. These goals were selected on the basis of
8-31
-------
CO
4
o
o
n
D CAR B-263; PTX 416, 18% EGR
O CAR B-415; PTX 516, 18% EGR
1972 CVS-C TEST PROCEDURE
10,000
TEST MILEAGE, mi
Figure 8-23. Nissan Durability Test Data
20, 000
8-32
-------
information extracted from the open literature and from extrapolation of Saab
test data. Since the durability data provided by Saab is limited to less than
11, 000 miles, derivation of meaningful deterioration factors is not possible
at this time (Ref. 8-14).
Prototype-to-production slippage factors for the 1975 systems are currently
not known. It is expected that this factor will be lower for catalyst systems
than for thermal reactor configurations which are generally more sensitive
to air/fuel ratio variations. Also, application of fuel injection systems is
expected to result in lower slippage factors compared with vehicles using
carburetors.
8.5.11 Toyo Kogyo
In order to meet the 1975 Federal emission standards, Toyo Kogyo has estab-
lished the following emission goals (in grams per mile) for rotary and reci-
procating spark ignition engines (Ref. 8-15):
System HC CO NO
'x
Rotary Engine, Thermal Reactor 0.29 2.3 2.3
Reciprocating Engine, Thermal Reactor 0.29 2.3 2.3
Reciprocating Engine, Oxidation Catalyst 0. 19 1.5 2. 3
Reciprocating Engine, Thermal 0. 19 1.5 2. 3
Reactor + Oxidation Catalyst
The emission goals of the thermal reactor systems were established on the
basis of a 50,000-mile prototype-to-production slippage factor of 1. 1, HC and
CO deterioration factors of 1. 3 each, and a NO deterioration factor of 1. 2.
j£
The selected deterioration factor for HC and CO is based on the experience
gained on 1970-72 model-year rotary engine vehicles using a thermal reactor.
8-33
-------
Lower goals were set for the catalyst systems, primarily because of a lack
of sufficient test data and experience with this type of system. The IIEC
targets were used as a guideline in setting the goals.
8. 5. 12 Toyota
Toyota has tentatively selected the following low-mileage emission goals (in
grams per mile) (Ref. 8-16).
HC = 0.19
CO = 1.5
=1.9
These goals were established by assuming emission averaging and perfor-
mance deterioration over the life of the system. In addition, a prototype-to-
production slippage factor of 1. 1 to 1. 2 was assumed. Although it has been
difficult for Toyota to predict accurately the deterioration rate of oxidation
catalysts over 50, 000 miles, factors as high as 3. 0 for HC and 2. 5 for CO
are indicated from Toyota bench test data for 25, 000 miles, using fuel with
a lead level of 0.01 to 0. 02 gm/gal. Toyota is optimistic with respect to
future reduction of these factors by means of improved catalysts. The NOT
-A.
deterioration factor is estimated to be approximately 1. 5.
8.5.13 Volkswagen
As stated by Volkswagen (Ref. 8-17), the following emission goals (in grams
per mile) have been selected for 1975 prototype vehicles:
HC - 0.17
CO = 1.4
NO = 0.12
x
8-34
-------
The NO goal was established on the basis of utilizing a reduction catalyst
as part of the Volkswagen emission control system which is being developed
to meet both the 1975 and 1976 emission standards. Although the reduction
catalyst will not be used on 1975 model vehicles (Ref. 8-18), NO emission
goals were not provided by Volkswagen for their 1975 system.
The emission goals are based on catalyst replacement at 20,000-mile inter-
vals and include an allowance for catalyst deterioration and laboratory test
variabilities. Prototype-to-production slippage was not taken into account
because of a lack of applicable production experience on systems of this
type (Ref. 8-18).
Volkswagen states that accurate prediction of system deterioration is currently
not possible. However, recent test data indicate that the catalyst reactivity
decreases in 20,000 miles by approximately 40 percent for HC and CO and
55 percent for
8.5.14
Since first-choice system durability data are currently not available, Volvo
has established the following emission goals (in grams per mile) on the basis
of very limited catalyst bench and vehicle test data (Ref. 8-19):
HC = 0.2
CO = 1.7
N0x = 1.2
These goals will be adjusted as more data become available from the 1975
emission control system test program. Data from one vehicle utilizing an
Engelhard PTX-416 catalyst indicate low HC and CO emissions and deterioration
factors. However, catalyst failure occurred at 29,900 miles.
8-35
-------
8.5.15 Catalyst Manufacturers
None of the catalyst manufacturers has established emission goals for 1975
vehicle/control systems. However, a number of these manufacturers have
provided encouraging emission durability data from a number of test vehicles.
The highlights from these programs are briefly discussed here.
The Houdry Division of Air Products has provided AMA durability data from
an early base metal catalyst which was tested in accordance with the 1972
CVS-C test procedure (Ref. 8-20). The emission data from this test are
depicted in Figure 8-24. As indicated in the figure, the emissions increase
approximately linearly with mileage. The average 4000- to 50, 000-mile
deterioration factors are 2. 19 for HC and 1.77 for CO. The 1975 standards
are exceeded at zero mileage.
Engelhard has provided high mileage emission data from a vehicle equipped
with a PTX-5 catalyst and driven over a city suburban route. The test data,
which are included in Section 5. 7.4, indicate very low HC and CO emissions
and deterioration factors. Although the vehicle has not completed 50, 000
miles and was not tested on the AMA cycle, the data are encouraging.
Data from New York police cars equipped with PTX-5 catalysts were also
provided by Engelhard (Ref. 8-21). The catalyst conversion efficiencies
computed from these data are presented in Figure 8-25. The HC conversion
efficiency decreases linearly with mileage, while the CO efficiency appears
to level off at approximately 10, 000 miles. Since the vehicles have not
accumulated sufficient mileage, these data should be used with caution.
Matthey Bishop has provided emission data for a subcompact Chrysler (U.K. )
Avenger vehicle tested by Johnson Matthey with an AEC-3A catalyst and lead-
sterile fuel (Ref. 8-22). The emissions from this vehicle are plotted in
Figures 8-26 to 8-28. As indicated, there is essentially no deterioration in
the CO and NO emissions. The high CO value at 24,000 miles (pre-service)
Ji
is attributed to choke problems. By linear extrapolation of the HC data, the
4000- to 50,000-mile HC deterioration factor is 3. 88.
8-36
-------
HOUDRY HN 1269 BASE METAL CATALYST
AC CMT14 260 cu.in. CONVERTER
INOOLENE CLEAR FUEL
350 CHEVROLET 2 bbl CAR 60328
1970 B WITH AIR
4972 FEDERAL TEST PROCEDURE (EPA)
HC DETERIORATION FACTOR = 2.19
CO DETERIORATION FACTOR =1.77
10,000
20.000 30,000
TEST MILES
40,000
50,000
Figure 8-24. Houdry Durability Test Data
1.0
I 0.1
I0'4
I 0.4
CJ
!M
S VEHICLE! EQUIPPED WITH
ENGELHARD PTJC-5 CATALYSTS
6-CYLINDER VEHICLES
5000
10,000
TEST MILES
IS, 000
10,000
Figure 8-25. New York Police Car Fleet Data
8-37
-------
0 I 1 1 1 1 I 1 1 1 1 1 1 1 1 ill 111
EMISSIONS
HC
AVENGER VEHICLE
1975 TEST PROCEDURE
20.000
CO
3
AVENGER VEHICLE
W5 TEST PROCEDURE
5.000
10.000
TEST MILES
15.000
20,000
NO
x
Figures 8-26, 8-27, 8-28. Johnson-Mathey Durability Test Data
8-38
-------
REFERENCES
8-1 American Motors Corporation, Letter to Mr. William D. Ruckelshaus,
Administrator, Environmental Protection Agency, 4 April 1972. '
8-2 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, "Technical Appendix to Summary Statement of Engelhard,
Addendum II, " 24 April 1972.
8-3 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the Clean
Air Act, " March 1972.
8-4 Chrysler Corporation, Technical Data Submittal provided by Chrysler
at the request of the EPA Suspension Request Hearing Panel, >
25 April 1972.
8-5 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II, 5 April 1972.
8-6 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
8-7 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency, Washington,
D. C., 26 April 1972 (recall).
8-8 General Motors Corporation, Technical Data Submittal provided by
GM at the request of the EPA Suspension Request Hearing Panel,
21 April 1972.
8-9 International Harvester, "Request for One-Year Suspension of 1975 HC
and CO Light-duty Emission Standards, " Submitted to EPA, Washington,
D. C., " 29 March 1972.
8-10 British Leyland Motors, Inc. , "EPA Hearing of Volvo Application for
Deferment of Emission Legislation Applicable to 1975 Model Year
Vehicles, " March 1972.
8-11 Daimler-Benz, "Statement of Daimler-Benz AG before the Environmental
Protection Agency, Washington, D. C.," April 1972.
8-12 Mitsubishi Motors Corporation, "A Status Report of Emission Control
for 1975 and 1976 Light-duty Vehicles," October 1971.
8-39
-------
REFERENCES (continued)
8-13 Nissan Motor Company, Ltd. (Datsun), "Summary Statement of
Information, " 5 April 1972.
8-14 Saab-Scania of America, Inc. and Saab-Scania AB, "Information
Submitted in Response to Subpoena dated March 17, 1972 of Environ-
mental Protection Agency, Washington, D. C. "
8-15 Toyo Kogyo Company, Ltd., "Statement of Toyo Kogyo Company,
Ltd. , " April 1972.
8-16 Toyoto Motor Company, Ltd., "A Summary of Toyota's Technology
and Processes for Meeting the 1975 Federal Emission Standards, "
5 April 1972.
8-17 Volkswagen of America, Inc., "Information and Documentary
Materials Relating to Volkswagen's Emission Research and Design
Effort to Meet 1975 Federal Emission Goals, " 10 April 1972.
8-18 Volkswagen of America, Inc., Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 10 April 1972.
8-19 AB Volvo, "Request for Suspension of the 1975 Emission Standards, "
9 March 1972.
8-20 Air Products and Chemicals, Inc. , Houdry Division, "Progress in
the Development of Automotive Emission Control Catalysts, "
13 April 1972.
8-21 Engelhard Minerals and Chemicals Corporation, Engelhard Industries
Division, "Summary Statement for EPA Hearings on Volvo Application
for One-year Suspension of Auto Emission Standards, " 10 April 1972.
8-22 Matthey Bishop, Inc., Technical Data Submittal provided by Matthey
Bishop at the request of the EPA Suspension Request Hearing Panel,
17 April 1972.
8-40
-------
9. INTERIM STANDARDS
9. i SUMMARY DISCUSSION
All thirteen automobile manufacturers appearing as witnesses at the EPA
Suspension Request Hearings have asked for a one-year suspension of the
1975 Federal emission standards and adoption of less stringent interim stan-
dards. In justifying their request, the automobile manufacturers contend
that the technology is currently not available to achieve the 1975 standards
on spark ignition, reciprocating engine-powered production vehicles.
Furthermore, the automobile manufacturers are extremely reluctant to
mass produce a catalytic emission control system without having success-
fully demonstrated vehicle/control system safety, performance, and
durability. To date, there is no data available that proves that mass-
produced vehicles can meet the 1975 emission standards at 50,000 miles
when operated under conditions simulating customer driving patterns.
The interim standards proposed by the automobile manufacturers and a
number of the catalyst suppliers are presented in Table 9-1. All of these
interim standards are based upon the concept of emission averaging and, in
the case of Ford, upon the satisfactory resolution by EPA of several regula-
tory issues, including fuel specifications, vehicle maintenance, and methane
allowance. The methane allowance is proposed by Ford to account for the
fact that, while the methane conversion efficiency of the catalyst is low, the
reactivity of the CH. hydrocarbon in the smog formation process is negligible.
With the exception of Ford and International Harvester, who propose to use
oxidation catalysts, the remaining auto manufacturers' suggested interim
standards will be achieved by engine modifications, including improved
carburetion, choke, and ignition systems.
9-1
-------
Manufacturer
Emission Control
Concept
I. DOMESTIC AUTOMOBILE MANUFACTURERS
American Motors
Chrysler
Ford
General Motors
International Harvester
Engine Modification
Engine Modification
Oxidation Catalyst
Engine Modification
Oxidation Catalyst
II. FOREIGN AUTOMOBILE MANUFACTURERS
British Leyland
Daimle r - Benz
Nissan
Saab-Scania
Toyo Kogyo
Toyota
Volkswagen
Volvo
Engine Modification
Engine Modification
Diesel Engine
Without Catalyst
Engine Modification
Engine Modification
Engine Modification
Rotary Wankel Engine
With Thermal Reactor
Engine Modification
Engine Modification
Engine Modification
III. CATALYST MANUFACTURERS
Chemico
Engelhard
W. R. Grace
Universal Oil Products
Catalyst Addition
Catalyst
Catalyst
Catalyst
Emissions, gm/mi
HC
3. 4
1. 5 to
2.0
1.6
1.5
3.4
1. 0 to
1. 15
3. 4
1. 5
0.41
3.4
3.4
(0.41)
3. 4
3. 4
3.4
CO
39
20 to
25
19
19
39
12 to
20
39
20
3. 4
39
39
-
(3.4)
39
39
39
N0x
3.0
2. 5 to
2.0
2.0
3. 1
3. 0
3. 0 to
1.75
3. 0
1. 5
3. 1
3.0
3.0
-
(3.1)
3.0
3. 0
3.0
Technology to meet 1975
standards available
1975 Standards or slightly
higher
0. 6 to
0.8
0.96
7 to
10
7.99
-
Manufacturers' Remarks
1974 Standards
To be selected within that range
Some models possibly without
catalyst
1974 Standards
Either combination feasible
1974 Standards
Meets 1975 Standards
1974 Standards
1974 Standards
Not selected ;
Good chance to meet 1975 Standards
1974 Standards
1974 Standards
1974 Standards
No test data supporting claim
-------
Daimler-Benz is optimistic with respect to meeting the 1975 standards
with the diesel-powered 220D vehicle. Toyo Kogyo expressed confidence
that the standards could be met with the rotary engine version of the
Mazda vehicle. However, both engine types cannot be produced in suffi-
cient quantities to create an impact on air quality in 1975-76. Further-
more, the excessive cost, the unfavorable prospects for meeting the 1976
NO standards, and the potential aldehyde (odor) problem are inherent dis-
x f
advantages of the diesel engine.
Two catalyst manufacturers, Engelhard and Chemico, are optimistic in terms
of meeting the 1975 standards, although neither one has demonstrated the
required emission control system durability over 50, 000 miles on the EPA
certification cycle. This optimism is based on the contention that further
improvements in the substrate, wash coat, and catalyst formulation are
likely to occur in time to be incorporated into 1975 emission control systems.
It should be recognized that suppliers would be favorably inclined toward the
establishment of standards which demand the use of catalytic converters.
With the exception of Chrysler, Ford, International Harvester, and Daimler-
Benz, all automobile manufacturers have proposed to adopt the 1974 emission
standards for 1975 reciprocating, spark ignition engine-powered vehicles,
primarily for the following stated reasons:
a. Promulgation of interim standards lower than the 1974 stan-
dards has little effect on improving air quality, as shown by
NAS (Ref. 9-1).
b. Adoption of more stringent standards would tend to dilute
current emission control system development efforts because
the automakers might then be inclined to select 1975 systems
using devices such as thermal reactors, which have little
chance of ever meeting the 1976 NO standard.
c. Excessive risk and system cost.
The interim standards proposed by Chrysler and Daimler-Benz are of the
order of 50 percent of the 1974 standards. Both companies would attempt to
achieve these levels by means of engine modifications only, possibly
9-3
-------
with the use of secondary air injected into the exhaust manifolds. This basic
approach is desirable because it minimizes the raw engine emissions. As a
result, potential catalyst heat-load problems will be minimized in future sys~
terns incorporating catalysts.
Ford and International Harvester propose interim standards somewhat below
those recommended by Chrysler and Daimler-Benz. Both Ford and Inter-
national Harvester project the use of oxidation catalysts in their interim sys-
tem vehicles, but Ford believes that the catalyst might be omitted on some
Ford models. In this case, catalytic systems could be introduced gradually
to gain the required field experience and to minimize the risk. Since the
emissions from the Ford 1972 and 1973 development fleets and the engine
emissions from the Ford "Riverside" fleet are substantially lower than the
1974 standards, the prospects appear favorable for this approach.
Catalyst replacement at 20,000 or 25, 000 miles has been discarded by Ford
on the basis of data which lead them to believe that catalyst deterioration is
primarily confined to the low mileage range. However, the Ford position
appears questionable in view of the vehicle durability test data submitted by
American Motors, General Motors, Matthey Bishop, and Ford. As discussed
in Section 8, most data from these manufacturers indicate a rather gradual
emission and catalyst effectiveness deterioration with mileage accumulation.
None of the other manufacturers has provided information regarding catalyst
replacement between 0 to 50, 000 miles.
9. 2 PROPOSED INTERIM STANDARDS
9. 2. 1 American Motors
American Motors considers compliance with the 1975 Federal emission stan-
dards to be technically unfeasible and recommends that the 1974 standards
and test procedures be continued through model year 1975 (Ref. 9 = 2),,
9-4
-------
This conclusion is based on the contention that the American Motors'
candidate catalytic converter system for 1975 is not sufficiently developed to
be released for production within the short time remaining before critical
production-related decisions have to be made. American Motors recommends
that selection of interim standards be based on the degree of control that can
be achieved with systems without catalytic converters. Furthermore,
American Motors states that the engineering efforts currently under way on
the 1975 system would be diluted if more stringent interim standards were
selected for 1975 and, therefore compliance with the 1975-76 emission stan-
r
dards would be further delayed.
Although one American Motors vehicle (Section 8) has met the 1975 HC and
NO standards for 50, 000 miles (CO was above the standard) American
X,
Motors does not believe that the adoption of these standards can be justified
on the basis of a single successful vehicle durability test over the relatively
"mild" EPA route. Furthermore, American Motors points out that on that
test, fuel was used with a lead and phosphorus contamination level of only
approximately 50 percent of the maximum allowed by the proposed EPA fuel
additive regulation.
Since the lowest HC and CO emissions achieved by 1972 and 1973 American
Motors certification vehicles are substantially below the 1974 standards
(Ref. 9-3), it appears that American Motors might be able to meet more
stringent requirements than the proposed 1975 interim standards at least on
some models. The data base for this judgment is presented in Figures 9-1
to 9-3 for a Matador 1972 certification vehicle (304CID, automatic, engine
modifications) and in Figures 9-4 to 9-6 for a Hornet 1973 certification
vehicle (232 CID, automatic, engine modifications). The data plotted in these
figures are adjusted to the 1975 test procedure. The curves drawn represent
an estimated fit to the data points. As indicated, the HC and CO emissions of
the 1972 vehicles increase by a factor of approximately 1.4 between 4,000
and 50, 000 miles, while NO remains essentially constant. While at 50, 000
Jv
miles the HC level shows little remaining margin, the CO emissions are
9-5
-------
u
1 f.0
vt
M
2
' ,.»'
CAR Oil-150
EKGIWC sw CID
tl MAINTENANCE
DATA &DJU3T&O TO IV75 TEST PDCCEOUBE
SO, CCS
OUBflBIUTY. Pi
EMISSIONS
HC
CAR Oil-ISO
CMUHE JM CID
tl kUINTCNANCC
DATA ADJUSTED TO "" TEST PROCEDURE
20,000 30.000 W.CtO SO. 000
DUMBIIITV. al
CO
CA* DII-ISD
f NOINI KM CIO
t| UAINTEKANCC
DATA ADJUSTED TO 1919 TEST PfiOCEOURI
0 10,080 20.000 $0,000 40,080 SO.C39
DUBSBIlltV, al
NO
Figures 9-1, 9-2, 9-3. American Motors Matador 1972 Certification Car
9-6
-------
I'
s
a
CAR D20-M.
ENGINE 2B CIO
11MAINTENANCE
DATA ADJUSTED TO 1979 TEST PROCEDURE
JO. 000 10.000
ouiuiuir. ! .
EMISSIONS
HC
CAR 010-91.
ENGINE IB CIO
tl MAINTENANCE
DATA ADJUSTED TO ltT9 TUT PROCEDURE
20,000 30.000
DUItllLITT. >l
CO
T
CAII D20-9L
ENGIIIE ttt CIO
11 MAINTENANCE
DATA ADJUSTED TO It79 TEST PROCEDURE
NO
10.000 30.000
OUIMIUIT. !
Figures 9-4, 9-5, 9-6. American Motors Hornet 1973 Certification Car
9-7
-------
less than 50 percent of the 1974 Standard. The 1973 vehicle shows
increasing HC emissions and decreasing CO emissions as mileage is
accumulated. No explanation was offered by American Motors regarding the
trend of the CO emissions. At 50,000 miles, the HC and CO emissions are
approximately 1.8 gm/mi and 11.7 gm/mi, which is substantially lower than
the 1974 standard. The NO emissions are above the 1974 standard between 0
x
and 12,000 miles. Although not discussed by American Motors, it seems
possible that the deterioration of the engine emissions may be reduced by
means of the projected improved carburetion, choke, and ignition systems.
American Motors did not provide information on maintenance requirements,
cost, and growth potential of the system projected for compliance with the
1975 interim standards proposed by American Motors.
9. 2. 2 Chrysler
In the opinion of Chrysler, the 1975 emission control system concepts with
catalysts or any other alternative control technique cannot be reduced to
practical hardware within the lead time remaining for 1975 production
(Ref. 9-4). For this reason, Chrysler emphasizes and is pursuing the
engine modification approach for 1975 model vehicles. The modifications
currently being investigated include improvements on the current Chrysler
"Cleaner Air System" and incorporation of electronic spark timing control,
EGR, carburetor altitude control, and exhaust port air injection on all
engines. Utilization of catalytic converters is not anticipated because of
severe catalyst durability problems encountered by Chrysler to date.
With these improvements, Chrysler projects to meet the following interim
standards (in grams per mile) with 1975 model vehicles:
1974 Recommended 1975 1975
Standards Interim Standards Standards
HC 3.4 1. 5 to 2. 0 0. 41
CO 39. 0 20 to 25 3. 4
NO 3. 0 2. 5 to 2. 0 3. 1
9-8
-------
The above emission ranges specified by Chrysler illustrate the tradeoffs
between maximum HC, CO and NO control. Chrysler states that the low
limits for all these pollutants probably cannot be met simultaneously in 1975.
According to Chrysler, the purchase price of a car meeting the interim stan-
cards would be substantially lower than that of a car equipped to meet the
1975 standards. Compared with a 1974 car, the retail price increase of the
two systems is $148 and $411, respectively (Ref. 9-4). The higher cost of
the system meeting the 1975 standards reflects the incorporation of catalytic
converter(s) and the partial thermal reactor(s) projected for that system.
The engine modifications required in the system designed to meet the pro-
posed interim standards are compatible with catalytic converter systems
which, in the opinion of Chrysler, are ultimately required to meet the 1975
standards. Incorporation of these engine modifications is considered both
desirable and necessary with respect to emission control system reliability
and durability, as well as vehicle driveability and safety.
9. 2. 3 Ford Motor Company
Ford contents that the technology to achieve the 1975 emission standards is
currently not available and, as a result, less stringent interim standards
should be established for 1975 model year vehicles. Based on engineering
judgment, Ford believes that the following combinations of interim standards (in
grams per mile) canbemetwith 1975 model Ford production vehicles (Ref. 9-5):
HC 1.6 1.5
CO 19.0 19.0
N0x 2. 0 3. 1
Ford's selection of these interim standards is contingent upon satisfactory
EPA resolution of several important regulatory issues which directly affect
Ford's emission control capabilities for 1975 vehicles. These issues include
allowable lead and phosphorus levels in the fuel, permission to average the
emissions of certification vehicles, introduction of a methane allow-
ance for vehicles equipped with catalytic converters, and establishment of
9-9
-------
maintenance procedures for durability/certification vehicles. Currently no
data are'available at Ford which demonstrate that the proposed interim stan-
dards can be achieved on production vehicles. However, Ford anticipates
that sufficient progress can be made to meet these levels by 1975.
The proposed interim standards are based upon utilization of a catalyst-only
system (no thermal reactor). According to Ford, these values represent the
limit of the technology available for 1975 production vehicles. Although Ford
anticipates that most of the 1975 vehicles will require an oxidation catalyst to
meet these interim standards, some models may be certified without catalysts.
In view of the low emissions achieved by Ford on the 1972 and 1973 model
development vehicle fleets at low mileage and the potential improvements in
the area of engine modifications, this approach appears feasible. On the
average, the emissions of the Ford 1973 development fleet vehicles are
2. 09 gm/mi HC, 17. 15 gm/mi CO, and 2. 42 gm/mi NO (based on the 1975
X
test procedure) (Ref. 9-6).
The 1972 vehicles were tested in accordance with the 1972 test procedure;
average emissions of 2. 37 gm/mi HC, 24. 2 gm/mi CO and 2. 22 gm/mi NO
were obtained. Using the 1975/1972 conversion factors derived by Ford for
the 1973 vehicles (0.90 for HC, 0.72 for CO, 1.02 for NO ), the 1975-
X.
equivalent emissions were computed for the 1972 vehicles. On this basis,
the 1972 and 1973 vehicle emissions are quite comparable. Of course,
these numbers must be adjusted to account for engine emission deterioration
over 50, 000 miles.
Test data for the Ford Riverside fleet provided by Engelhard indicate average
zero mileage "raw" engine emissions of approximately 1. 45 gm/mi HC,
25. 1 gm/mi CO and 2. 24 gm/mi NO .
x
The interim standards proposed by Ford have been developed from projec-
tions of average emissions obtained from low mileage, best-effort catalyst-
only systems developed in 1971 and deterioration factors derived from five
vehicles that had completed 50, 000 miles of durability testing. In addition,
9-10
-------
Ford applied a factor of 1. 2 to account for test data uncertainties. According
to Ford, the average sales-weighted low mileage emissions from these best-
effort vehicles are 0. 45 gm/mi HC, 6. 5 gm/mi CO and 1. 2 gm/mi NO .
JL
Considering the low mileage HC and CO emissions achieved on the Riverside
vehicles, these HC and CO values appear to be conservatively high. The low
mileage to 50,000-mile emission deterioration factors of 2.8 for HC, 2.4 for
CO and 1. 4 for NO were derived by Ford principally from the 1974
Jv
California fleet test data. Although these systems are not considered repre-
sentative of 1975 configurations by the report team, the deterioration factors
selected by Ford are considered reasonable approximations. These aspects
are discussed in Section 8. Ford intends to develop more accurate deteriora-
tion factors upon completion of the Riverside test program. However, the
Engelhard catalysts utilized on these vehicles are not of the improved type
and, as a result, the emission performance of these systems may not ade-
quately reflect current state-of-the-art technology.
Although the question of catalyst replacement and its effect on interim stan-
dards has not been fully investigated by Ford, the emissions benefit is con-
sidered small unless the catalyst were replaced at unreasonably short
intervals. This conclusion by Ford is based on the data from the 1974 ,
California fleet tests. As discussed in Section 8, these data indicate that
catalyst deterioration occurs primarily during the early stages of catalyst
usage. Following an initial rapid rise, the emissions remain essentially f
constant up to very high mileage. Since these trends are contradictory to «,
other Ford data and to most ot the data provided by other manufacturers,
the rationale for the Ford conclusion regarding catalyst replacement is not
readily apparent.
No information was provided by Ford on maintenance, cost and growth
a
potential of the proposed interim system. However, the basic design of
this system appears to be identical to the systems projected by Ford to
meet the 1974 standards.
9-11
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9. 2. 4 General Motors
In requesting suspension of the 1975 Federal emission standards, General
Motors recommends utilization of the 1974 standards as the interim standards
for 1975 model-year vehicles. General Motors states that continuing the
1974 standards for an additional year will allow them to concentrate on sys-
tems that will meet'the 1975 standards at a later date, whereas more stringent
interim standards might cause serious dilution of the total emissions-control
effort.
To justify this position, General Motors (Ref. 9-7) refers to the NAS Study
and stresses the small impact that a one-year suspension would have on
ambient air quality.
Although General Motors believes that some improvement over the 1974 stan-
dards might be achieved by selective use of certain emission control system
components, they are unable at this time to establish specific numbers on
attainable levels for a number of reasons. These concern unresolved ques-
tions regarding fuel composition, emission averaging, assembly line testing,
warranty, and recall procedures. In addition, General Motors feels that the
control system performance and durability has not been adequately demon-
strated. As a result, the capability of the advanced emission control system
in terms of consistently achieving emission levels below the 1974 standards
remains in doubt.
Considering the emissions of General Motors 1972 production vehicles at
4, 000 miles (between 59 percent and 75 percent of the 1972 standards,
Ref. 9-7), it appears that General Motors should be able to meet more
stringent standards in 1975 than the 1974 levels.
9. 2. 5 International Harvester
As stated in their suspension request (Ref. 9-8) International Harvester will
not be able to meet the 1975 emission standards on 1975 model vehicles.
9-12
-------
However, assuming availability of fuel with sufficiently low levels of
contaminants and application of the emission-averaging concept, International
Harvester anticipates meeting either of the following two combinations of
interim standards (in grams per mile):
HC 1.0 1.15
CO 12. 0 " 20. 0
NO 3.0 1.75
x
Although lower emission levels have been achieved by International Harvester
on low-mileage research and development vehicles and engines, selection of
more stringent standards is believed not to be justified in view of the rapid
performance deterioration of current systems and the nature of the International
Harvester product line. It is further suggested by International Harvester to
limit the interim standards to 10 percent of a manufacturer's production
volume in order to gain field experience with these emission systems on a
lower-risk scale.
The emission control system that would be used by International Harvester
to meet these interim standards would incorporate an oxidation catalyst,
which is also a component of the system currently projected to comply with
the 1975 standards.
Considering their low-volume production and the problems related to heavier-
duty vehicles, International Harvester estimates the retail cost of the 1975
emission control system to be approximately $450.
9.2.6 British Leyland
Although they meet the 1975 Federal emission standards at low mileage,
British Leyland suggests that the 1974 standards be adopted as interim stan-
dards for 1975 for two reasons (Ref. 9-9). First, the required durability of
the projected 1975 emission control system has not been demonstrated and,
second, establishment of interim standards between the 1974 and 1975 standards
would not alleviate the durability and installation problems, but might
9-13
-------
divert efforts to a different system and further delay achievement of the
1975 emission standards. British Leyland also states that sufficient lead
time is not available to design and develop a new or modified system to meet
interim emission standards in 1975.
9. 2. 7 Daimler-Benz
Daimler-Benz produces a number of spark ignition engine models and one
diesel engine model for passenger vehicle applications.
With respect to spark-ignition engines, Daimler-Benz has revised its
earlier position (Ref. 9-10) of only being able to meet the 1974 standards on
1975 vehicles and is now of the opinion that the following interim standards
(in grams per mile) can be met (Ref. 9-11):
HC 1.5
CO 20.0
NO 1.5
x
Selection of these interim standards is based on the use of an emission con-
trol system without a catalyst. Although incorporation of a catalyst might
further reduce the emissions, engineering release of such a system is not
feasible at this time because of the uncertainties and risks associated with
current catalyst configurations.
Daimler-Benz believes that the 1975 standards (for gasoline -powered
vehicles) can be met by the 2. 2-liter diesel vehicle without the use of a
catalyst. There are indications that NO emissions as low as 1. 0 gm/mi
could be achieved by means of adjustments in the diesel combustion process.
According to Daimler-Benz, this engine cannot be produced in sufficient
quantity by 1975 to have an impact on air quality.
9. 2. 8 Mitsubishi
Since Mitsubishi was not a witness at the recent EPA Suspension Request
Hearings, there is no information available on Mitsubishi's position with
9-14
-------
respect to interim standards. However, Mitsubishi has submitted the
following best-engine emission data (in grams per mile) obtained in accor-
dance with the 1975 test procedure (Ref. 9-12):
HC 1.7
CO 23.5
NO 1.43
x >
These levels, which are considered by Mitsubishi to be the ultimate that can
be achieved by means of engine modifications, are similar to Chrysler's pro-
posed interim standards.
9. 2. 9 Nissan
Nissan states that they are unable to meet the 1975 Federal emission stan-
dards on 1975 model vehicles, and recommends adoption of the 1974 standards
for 1975 (Ref. 9-13). From the point of view of system reliability and dura-
bility, Nissan has no proven system for mass production other than that
which satisfies the 1973 standards. Nissan believes that adoption of more
stringent interim standards would only disrupt current efforts aimed at
meeting the 1975-76 emission standards at a later date.
Considering the emissions from the Nissan 1972 certification vehicles
(1. 86 to 2. 25 gm/mi HC, 18. 2 to 19. 5 gm/mi CO and 1. 98 to 2. 92 gm/mi NOx),
it appears that Nissan might be able to meet interim standards below the 1974
levels.
9. 2. 10 Saab-Scania
Saab-Scania states that the 1974 HC and CO standards should be considered
as interim standards for the 1975 model year, if the 1975 standards are
suspended (Ref. 9-14). i
According to Saab, the emissions from their current vehicles have already
been minimized by means of engine modifications to a point where further
significant reduction cannot be expected without the use of thermal reactors
9-15
-------
and/or catalytic converters. To date, adequate durability and reliability
of these components have not been demonstrated, and incorporation of
unproven systems is not considered by Saab to be in the public interest.
Although there are indications that the emissions from the 1973 Saab certifi-
cation vehicles are lower than the 1974 standards, Saab feels that adoption of
standards more stringent than the 1974 values is not justified on that basis
alone for two reasons. First, the certification vehicles are prototypes and
not production vehicles and, second, the certification durability test is not
yet complete. However, under questioning by the EPA Hearing Panel
(Ref. 9-15), Saab admitted that more stringent interim standards could pos-
sibly be met by Saab 1975 model year vehicles.
Compliance with the interim standards proposed by Saab will be accomplished
by means of engine modifications combined with an improved fuel-injection
system.
9.2.11 Toyo Kogyo
Based on available data, Toyo Kogyo is pessimistic with respect to meeting
the 1975 standards with spark ignition engine-powered vehicles (Ref. 9-16).
Conversely, the prospects of meeting these standards with rotary engine
vehicles are rather bright, although the 50, 000-mile durability of the thermal
reactor system used on that vehicle remains to be confirmed (Ref. 9-16 ).
Since thermal reactors have been used successfully by Toyo Kogyo on current
rotary-engine powered vehicles, no unsurmountable problems are anticipated
by Toyo Kogyo for that vehicle type.
9.2.12 Toyota
Toyota states that the 1975 emissions standards are too stringent and far
beyond its current technological capabilities. Therefore, Toyota requests
adoption of the 1974 standards for 1975. Establishment of more stringent
standards is considered undesirable by Toyota because current efforts aimed
at meeting the 1975 standards would be disrupted (Ref. 9-17).
9-16
-------
9. 2. 13 Volkswagen
Based on the results from the emission control system research and develop-
ment work conducted to date, Volkswagen has concluded that the 1975 emis-
sion standards cannot be met with 1975 Volkswagen vehicles (Ref. 9-18).
Therefore, Volkswagen recommends adoption of the 1974 standards as
interim standards for 1975. According to Volkswagen, more stringent interim
standards might result in the development and adoption of control systems
having little or no growth potential. Furthermore, the effect of more
stringent interim standards on air quality is minute.
9. 2. 14 Volvo
I
Volvo has stated that compliance with the 1975 standards is not possible at,
this time and adoption of the 1974 standards for 1975 vehicles is urgently
requested (Ref. 9-19).
In the opinion of Volvo, the emissions of current engines cannot be substan-
tially reduced from current levels by means of engine modifications and EGR
alone, and catalytic converters and thermal reactors are required to meet
the 1975 standards. Since the durability of these components is still an
unresolved problem area, Volvo is unable to justify the incorporation of such
devices into their 1975 vehicles at this time.
9. 2. 15 Chemico
Chemico has stated that the technology required to meet the 1975-76 emis-
sion levels is available at Chemico (Ref. 9-20), but that catalyst contamina-
tion by fuel additives must be prevented and the regulations must be modifie'd
to allow bulk catalyst addition at regular maintenance intervals. Chemico
did not provide high mileage test data to support this statement.
9. 2. 16 Engelhard
It is Engelhard1 s firm belief that current efforts to meet the 1975 standards
will be successful provided development programs now in progress throughout
the industry are not permitted to slacken. Conversely, if implementation of
9-17
-------
the standards were postponed by one year, or if the standards were relaxed
significantly, then compliance with the air quality standards would be
unnecessarily delayed (Ref. 9-21).
Engelhard is not aware of any inherent reasons why the catalyst cannot last
50,000 miles providing it is not subjected to poisons or over-temperature
conditions. Furthermore, Engelhard states that the likelihood of successful
development of an improved, second-generation PTX catalyst before model
year 1975 need not interfere with automotive companies' plans for including
PTX converters in 1975 model year production planning considerations.
9. 2. 17 W. R. Grace
In the opinion of Grace (Ref. 9-22), it is probably not technologically feasible
at this time to meet the 1975 emission standards (to 50, 000 miles). Based on
current Grace technology, the HC and CO standards will be exceeded between
5, 000 to 10, 000 miles. According to Grace the following HC and CO emis-
sion levels (in grams per mile) should be attainable for 50, 000 miles:
HC 0. 6 to 0. 8
CO 7 to 10
These values are based upon the emissions from 1970-71 vehicles, and
catalyst deterioration factors computed by Grace from test data.
9., 2. 18 Universal Oil Products
Universal Oil Products is very pessimistic regarding the development in the
near future of a practical, cost-effective system which is capable of meeting
the 1975 standards, and recommends that the following emission values (in
grams per mile) be adopted as interim standards (Ref. 9-23).
HC 0.96
CO 7.99
The National Academy of Sciences' recommendations permitting catalyst
change and averaging of emissions should also be adopted (Ref. 9-23).
9-18
-------
REFERENCES
9-1 National Academy of Sciences, "Semiannual Report," prepared by
The Committee on Motor Vehicle Emissions, Division of Engineering,
National Research Council, 1 January 1972.
9-2 American Motors Corporation, Letter to Mr. WilliamD. Ruckelshaus,
Administrator, Environmental Protection Agency, 4 April 1972.
9-3 American Motors Corporation, Technical Data Submittal provided by
AMC at the request of the EPA Suspension Request Hearing Panel,
25 April 1972.
9-4 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the
Clean Air Act, " March 1972.
9-5 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards," Volumes I and II, 5 April 1972.
9-6 Ford Motor Company, Technical Data Submittal provided by Ford
at the request of the EPA Suspension Request Hearing Panel,
26 April 1972.
9-7 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards, " Volumes I and II, 3 April 1972.
9-8 International Harvester, "Request for One-Year Suspension of 1975
HC and CO Light-Duty Emission Standards, " Submitted to EPA,
Washington, D. C. , 29 March 1972.
9-9 British Leyland Motors, Inc. , "EPA Hearing of Volvo Application
for Deferment of Emission Legislation Applicable to 1975 Model
Year Vehicles," March 1972.
9-10 Daimler-Benz, "Statement of Daimler-Benz AG before the Environ-
mental Protection Agency, Washington, D. C., " April 1972.
9-11 Mercedes-Benz Company (Daimler-Benz AG), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental Protec-
tion Agency, Washington, D. C. , 19 April 1972.
9-12 Mitsubishi Motors Corporation, "A Status Report of Emission Control
for 1975 and 1976 Light-duty Vehicles, " October 1971.
9-19
-------
REFERENCES (Continued)
9-13 Nissan Motor Company, Ltd. (Datsun), "Summary Statement of
Information, " 5 April 1972.
9-14 Saab-Scania of America, Inc. and Saab-Scania AB, "Information
Submitted in Response to Subpoena, dated March 17, 1972, of
Environmental Protection Agency, Washington, D. C. "
9-15 Saab-Scania, Inc., Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C. ,
12 April 1972.
9-16 Toyo Kogyo Company, Ltd., "Statement of Toyo Kogyo Company,
Ltd. , " April 1972.
9-17 Toyota Motor Company, Ltd. , "A Summary of Toyota's Technology
and Processes for Meeting the 1975 Federal Emission Standards, "
5 April 1972.
9-18 Volkswagen of America, Inc., "Information and Documentary
Materials Relating to Volkswagen's Emission Research and Design
Effort to Meet 1975 Federal Emission Goals, " 10 April 1972.
9-19 AB Volvo, "Request for Suspension of the 1975 Emission Standards,"
9 March 1972.
9-20 Chemical Construction Corporation (Chemico), "Statement to the
Environmental Protection Agency, Suspension Request Hearing,
Motor Vehicle Pollution Control," 21 April 1972.
9-21 Engelhard Minerals and Chemicals Corporation, Engelhard
Industries Division, "Summary Statement for EPA Hearings on
Volvo Application for One-year Suspension of Auto Emission
Standards," 10 April 1972.
9-22 W. R. Grace and Company, Transcript of Proceedings'-- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 18 April 1972.
9-23 Universal Oil Products Company, "UOP Position Statement for
EPA Hearings on One-year Suspension of 1975 Automobile
Emissions Standards," 17 April 1972.
9-20
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10. MAINTENANCE, SAFETY, AND COST
10.1 MAINTENANCE
As the levels of automobile emissions drop, proper engine and emission con-
trol maintenance can have an increasingly larger effect on air quality. At the
low emission levels of cars meeting the 1975-76 standards, if a small per-
centage of the car population has malfunctioning engines or emission control
systems, the total amount of pollutants released to the atmosphere by all of
the automobiles designed to meet the 1975-76 standards could double.
Ensuring that all vehicles, engines and emission control systems are oper-
ating properly is a very difficult undertaking. Historically, for financial and
convenience reasons, American car owners have not practiced preventive
maintenance on a large scale, tending to perform maintenance or repairs
only when vehicle performance has deteriorated markedly. Since vehicle
performance may be unaffected or may actually improve if certain elements
of the emission control system fail or deteriorate in their effectiveness,* it
is very questionable whether the car owner will, at his option, maintain these
devices in good repair (Ref. 10-1). Because of this, EPA has felt it is
extremely important to certify only emission control systems incorporating
designs which require minimal maintenance and repair. Accordingly, its
50, 000-mile durability test procedure for certification currently restricts
maintenance to one servicing of the ignition and carburetor system. No
servicing of the emission control system is permitted. .
*One example is the EGR system. The recirculated exhaust is an inert diluent
which effectively reduces engine size and hence power output. It also decreases
fuel economy. Plugging of the EGR system or an EGR valve failure, which
reduces the amount of recirculated exhaust flow, actually would improve
vehicle performance. Another example is the catalyst; its failure, in most
instances, would go unnoticed by the vehicle operator.
10-1
-------
However, as a result of problems in passing the 50, 000-mile durability test,
EPA has presently under development proposed regulations that -would allow
increased maintenance under certain guidelines . These regulations contem-
plate catalyst replacement and other reasonable maintenance. EPA would
consider approving EGR valve maintenance if the valve malfunction was such
as to cause vehicle performance deterioration leading the car owner to have
the defect remedied (Refs. 10-2 and 10-3). To achieve this result, it has
been suggested that the EGR system should be redesigned so as to fail only
in the "on" position. Several automobile companies (e.g., Ref. 10-1) have
declared this to be (1) undesirable, and (2) unsafe, on the following bases:
(1) if the EGR valve remains in the open position upon malfunction of the
system, the car cannot be started; and (2) failure of the EGR system might
cause sudden power loss at an undesirable time. Examples of the latter are
during car-passing maneuvers (at wide-open throttle EGR is normally off in
many systems) or during deceleration on a freeway where the engine may
stall if EGR is suddenly applied, leading to loss of power brakes and steering.
Preliminary estimates of catalyst replacement cost by catalyst manufacturers
range between $20 and $100, enough money to make voluntary catalyst replace^
ment very questionable, since no vehicle performance degradation will
ordinarily be incurred. Chrysler (Ref. 10-1) has suggested gradual artifi-
cially induced performance degradation, controlled by an emission sensor,
as an approach to ensure catalyst replacement. No such devices presently
have been invented.
The situation may be worse than indicated by the problems in attempting to
pass the 50,000-mile durability test. Many of the automobile-companies
have expressed the opinion that the EPA durability test is a relatively easy
test compared with the operating conditions to which many cars are exposed.
The passing of a prescribed 50, 000-mile test by a very limited number of
cars does nothing but ensure that a very small part of a large fleet of vehicles
is operating properly. Mandatory inspection, test, and correction of
defective emission control systems of all used vehicles is another alternative
10-2
-------
to maintenance-free systems, but it too has its problems, e. g. , cost,
inconvenience, lack of a suitable test, and long periods of vehicle operation
between tests.
In summary, it can be stated that no effective approach has yet been found
which will ensure that the emission control system on practically all cars
will continue to function properly.
10. 2 SAFETY
10. 2. 1 General
The primary safety issues associated with proposed 1975-76 automobile
emission control systems are:
a. Poor car-passing performance.
b. Increased fire hazard.
c. Possible sudden and catastrophic failures during critical
situations of automobile components (such as ignition or
fuel system) due to the excessive heat of the emission
control system.
10. 2. 2 Poor Passing Performance
With 1975-76 emission control systems, car-passing performance may be
degraded because of the use of EGR, changes in spark ignition timing for
emission control, higher exhaust system engine backpressure, and lower
compression ratios required by the use of unleaded gasoline necessitated by
lead-sensitive catalyst systems.
Some manufacturers propose to cut off EGR at wide-open throttle in order
to retain as much performance as possible. Some manufacturers have
indicated that it may be necessary to drop several of their lower-powered
economy models in order to achieve safe driveability.
10.2.3 Fire Hazard
The possibility of increased fire hazard in automobiles equipped with 1975-76
emission control systems is due to the higher temperatures in the exhaust
10-3
-------
system (including the thermal reactor and/or catalytic converter). These
increased temperatures are the result of the oxidation of the HC and CO
emissions and are highest when the engine is operated at a very rich
mixture. The worst operating conditions are:
a. Choked engine operation (particularly bad with an engine
which is cranked a long time before starting and which
accumulates fuel in the catalyst system).
b. High-power operation for a long period of time, e. g. , very
high highway speeds or when pulling a trailer on freeways or
mountain grades. (To increase power, the engine is operated
richer. )
c. Coasting for a long period of time, e. g. , descending a
mountain grade (very rich mixture engine operation).
d. High altitude operation without altitude compensation features
in the engine fuel control system (results in rich engine
mixture).
e. Misfiring spark plug which causes engine exhaust
enrichment.
f. Engine mixture enrichment to reduce NO emissions and/or
enhance thermal reactor emission reduction performance.
Proposed approaches to reduction or elimination of the increased fire hazards
and some of the problems associated with these approaches are:
a. Time limit on engine cranking (highly inconvenient).
b. Carburetor modification to prevent engine enrichment under
high-power operating conditions (reduces engine performance,
does not protect against a misfiring plug, may result in poor
driveability, and particularly for 1976, nonachievement of the
NO standard).
X.
c. Reduction of heat emission from the exhaust system by
insulation and/or forced-air cooling.
d. Overtemperature sensor which reduces secondary air flow
or activates exhaust by-pass for thermal reactor or catalyst
(very high protective system reliability is a must; if this is
the only protection system, it may be activated many times
during the life of the car).
10-4
-------
The overall fire hazard situation assessment of the automobile companies,
at least for 1975, ranges from serious concern to reasonably happy. No
one who is depending on an overtemperature-controlled by-pass valve is
extremely confident of achieving a satisfactory solution to the fire hazard
^problems of the emission control system.
10.2.4 Catastrophic Component Failures
The combustion of fuel-rich engine exhaust in the emission control system
can raise engine compartment temperatures significantly. Located in the
engine compartment are many vital vehicle components which can malfunction
in an unsafe manner as a result of these high temperatures. Examples of
such malfunctions are the breakdown of electrical insulation on wires for the
ignition and lights, which could cause sudden loss of power or headlights at
critical times; vapor lock in the hydraulic brake or power steering systems;
loss of vacuum for power brakes due to hose failure; and fuel system vapor
lock.
The problems caused by high engine compartment temperatures have caused
many automobile manufacturers to reject thermal reactors. Other approaches
to alleviate engine compartment temperature problems are the insulation of
8
critical components or heat sources such as catalysts. With respect to
catalysts, the preferable approach has been to try to locate them outside of
the engine compartment. But this has the disadvantage of making rapid
catalyst warm-up difficult and of increasing emissions during a cold start.
10.3 COSTS
10. 3. 1 General
The major factors to be considered in evaluating the cost of an emission
control system are:
a. The increase in the purchase price of the car due to the
addition of the emission control system.
10-5
-------
b. Any increased maintenance cost for the car over its
lifetime as a result of the addition of the emission control
system.
c. Any increased fuel cost over the life of the car due to the
addition of the emission control system. This includes fuel
cost increases due to increases in the cost per gallon of
fuel and decreases in engine efficiency.
10. 3. 2 Increased Purchase Price
Some estimated increases in "sticker price" of cars equipped with emission
control systems to meet 1975 standards, over an uncontrolled emission
vehicle, are discussed in the following paragraphs.
10. 3. 2. 1 American Motors
American Motors estimates the cost of its projected 1975 system to the
customer at $255 (Ref. 10-4). The projected 1975 system is similar to the
Ford HC/CO catalyst system although it is not clear whether the American
Motors system incorporates a catalyst by-pass protection system.
10.3.2.2 Chrysler
Chrysler estimates the cost of their first-choice 1975 system at $412
(Ref. 10-1). This system is the same as the Ford HC/CO catalyst system
plus a small or "partial" thermal reactor. (The addition of the thermal
reactor could explain the cost differential between Ford and Chrysler. )
10.3,2.3 Ford
Ford has estimated costs for a number of potential 1975 emission control
systems as shown below (Ref. 10-5). All systems include, in addition to
the components shown, EGR, secondary air pumps, modified carburetors
and distributors, and induction-hardened valve seats.
10-6
-------
Projected Customer
Retail Cost, $
HC/CO Catalyst 370
Thermal Reactor 400
Dual HC/CO Catalyst* 440
HC/CO Catalyst plus Thermal Reactor 510
Dual HC/CO Catalyst plus Thermal Reactor 580
*r
'As used here, the dual catalyst has one HC/CO catalyst near the
front of the vehicle and an additional one near the rear.
10.3.2.4 General Motors
The estimated increase in retail price of a vehicle equipped with the pro-
jected 1975 General Motors emission control system is $300 (Ref. 10-6).
The emission control system is similar to the Ford HC/CO system. (The
$70 difference in price may be due to the incorporation of a catalyst over-
temperature control in the Ford system. )
10. 3. 3 Maintenance Costs
Maintenance costs include tuneups and parts replacement (such as spark
plug or catalyst replacement) necessary to keep emissions at a low level.
Very little factual information is available on the consumer-use maintenance
required for cars equipped with emission control systems meeting the
1975-76 standards because of the limited field experience with these systems.
There have been various opinions offered on the cost of catalyst replacement
or refurbishment. The costs estimated per refurbishment have ranged from
$20 to over $100. The low numbers correspond to replacement of pellets
only, in a pellet-type catalyst. If catalyst refurbishment were necessary
every 25,000 miles and the cost per refurbishment were on the high side of
the cost range discussed above, a major increase in car maintenance costs
would result.
10-7
-------
10.3.4 Fuel Costs
Fuel costs of automobiles capable of meeting 1975-76 standards -will be
higher than those of uncontrolled vehicles, because of higher fuel consumption
projected for the 1975 vehicles. This loss in fuel economy is due to the
incorporation of the emission control system, reduction of the engine com-
pression ratio, and increased vehicle weight. Chrysler has stated that the
fuel economy (miles per gallon) of its cars for 1975 and 1976 will only be
81 percent and 70 percent, respectively, of that of a pre-emission control
car; e.g., 1968 year model (Ref. 10-7). The 1976 fuel economy could
improve significantly if a suitable NO catalyst were developed, but progress
to date on such development has not been encouraging.
Chrysler's projected fuel economy degradation is typical of that reported by
other manufacturers. Causes for the poor fuel economy are:
a. Decreased compression ratios (due to the use of lower
octane number unleaded gasoline because catalysts will
not tolerate leaded gasoline).
b. Ignition spark timing changes to maximize emission control
rather than fuel economy.
c. EGR for NO reduction.
Ji.
d. Operation at richer air/fuel ratios to maintain acceptable
. and safe driveability with EGR.
For the range of fuel economy reductions indicated above, the fuel cost
increases over a car's lifetime (85,000 miles average) are estimated to be
of the order of $500 for 1975-type systems and $1000 for cars equipped with
1976-type emission control systems, an amount which is larger than the
increase in the sticker or purchase price of the car due to the addition of the
emission control system. If every car on the road eventually had emission
controls of this type, the nation's increased fuel cost would be $5 to $10 billion
annually, and of course the rate of depletion of crude oil reserves would
increase markedly. Development of emission control systems which permit
better fuel economy is obviously highly desirable.
10-8
-------
REFERENCES
',*-'. r
10-1 Chrysler Corporation, Transcript of Proceedings -- Auto Emissions
Extension -- Environmental Protection Agency, Washington, D. C.,
20 April 1972.
10-2 Letter from E. O. Stork, Director, Mobile Source Pollution Control,
to Dr. F. W. Bowditch, General Motors Engineering Staff, November
19, 1971.
10-3 Letter from E. O. Stork, Director, Mobile Source Pollution Control,
to Dr. F. W. Bowditch, General Motors Engineering Staff,
December 9, 1971.
10-4 American Motors Corporation, Technical Data Submittal provided
by AMC at the request of the EPA Suspension Request Hearing
Panel, 20 April 1972.
10-5 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II,
5 April 1972.
10-6 General Motors Corporation, Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 17 April 1972.
10-7 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the
Clean Air Act, " March 1972.
10-9
-------
11. PRODUCTION LEAD TIME
11.1 INTRODUCTION
11. 1. 1 Data Sources
The primary sources of data for the discussion of automotive production
lead time presented in this section are (a) past and current submittals by
the automobile manufacturers pertaining to progress in the development of
emission control systems for 1975 model year cars, (b) testimony given
in the recent EPA hearings on the request for suspension of the 1975 Federal
exhaust emission standards, and (c) data available in the open literature on
lead time requirements for the production implementation of new automotive
vehicle designs. The pertinent information acquired from these sources
is less than adequate for a detailed treatment of the lead time topic; the data
are used solely to highlight some general points in the discussion that follows.
11.1.2 Terminology
Production lead time is defined as the period between commitment by manage-
ment of capital funds for production facilities and the date of achievement
of the first mass-produced article. This period is selected by the manufacturer
so as to provide sufficient time to specify, design, procure, install, and
checkout production tooling and equipment and to accelerate the manufacturing
process to full-volume output. Normally, the commitment of funds for pro-
duction is not made until "proof-of-design" prototype testing has been com-
pleted and the suitability of the basic design and operating features of the
system has been established or verified.
11. 1. 3 Schedule Considerations
The operations which must be accomplished during the production lead time
interval include: production engineering, tool construction and tryout, pilot
11-1
-------
assembly, and production build up. In addition to allotting time for these
activities, sufficient time must be provided for contingencies such as delays
due to equipment, labor, or material shortages; labor strikes; and equipment
checkout problems. Accordingly, the lead time must be lengthened, to a
degree governed partly by past experience and the complexity of the product
to be manufactured. Frequently, as in the case of a program with a fixed end
date (the first day that full production capacity is reached), economic con-
siderations demand that a large amount of time be reserved to minimize the
possibility of missing the designated milestone. However, overly conservative
scheduling can lengthen the lead time excessively which then increases labor
costs. Conversely, the compression of lead time can also lead to increased
costs because of the need for overtime labor in both the automobile and
supplier manufacturing facilities.
In summary, lead time is governed largely by equipment procurement/
installation/checkout time and by the need to minimize program costs; it is
flexible to the extent that the duration is defined on the basis of a number of
judgment factors.
Over the years, the transition from hand labor to machine tasks and then
to computer-controlled automated operations has led to increased lead times.
This has naturally arisen from the requirement by the equipment manufacturers
to devote more time to the design and checkout of the highly specialized and
sophisticated equipment required for modern, high-volume-rate assembly line
operations. Great care in equipment design and assembly line design is
necessary because the magnitude of the associated economic investment
reduces the allowable margin for error.
11.2 PACING ITEMS
With regard to 1975 emission control systems components, each manufacturer
has identified one or more factors which control or define his production
11-2
-------
lead time requirement. In each case, the most critical items cited were
the fabrication of the catalytic converter and the completion of durability
tests currently being conducted for the verification of the complete emission
system design. The manufacturing schedule for catalytic converters is
lengthy; it is believed that this is due primarily to the fact that the converter
design represents a new technology and, in contrast to most automotive com-
ponents, involves a source of supply that is unfamiliar with and unproven
by automotive industry experience in high-volume production practices,
procedures, and requirements. Hence, the lead time requirement encompasses
the additional uncertainties and contingencies associated with new vendor
associations.
The following paragraphs discuss the particular manufacturing/lead time
problems emphasized by the major domestic automobile manufacturers.
Of great concern to the automobile manufacturer is the need currently to
commit to production the design of the engine, chassis, and body without
full knowledge of the impact of emission control equipment on these major
pieces of hardware. Design modifications after a period of time become
very costly in terms of overtime labor necessary to adhere to schedules.
11.2.1 American Motors
American Motors states that body/frame changes required to accommodate
the catalytic converter are the critical pacing lead time items. Production
drawings for these body changes must commence on June 1, 1972 (Ref. 11-1).
11.2. 2 Chrysler
Chrysler's decision on the type of catalyst to be used in its emission control
system is the critical pacing item. It has stated that the final system
definition is required 31 months prior to the start of production (January
1972). Formal commitment to a catalyst supplier is required 28 months
prior to the start of production (April 1972) (Ref. 11-2).
11-3
-------
11.2.3 Ford
While tooling is not a controlling factor, Ford's overall lead time requirement
is based on the time required to prove out new hardware facilities and equip-
ment and to redesign its mass production processes. In association with
Engelhard, the catalyst supplier, two facilities are planned for the production
of the catalytic converter. One of these, Plant #1, is a pilot production plant
due to be in full operation by April 1, 1973 (ultimately, the plan is to convert
this plant to a production facility). The other facility, Plant #2, is due to be
in full operation by April 1, 1974; site procurement was planned for May 1,
1972. A decision on the source of supply for the catalytic converter canister
has not been made. (Ref. 11-3. )
11.2.4 General Motors
General Motors'longest lead time requirement concerns the fabrication of
electron beam welders to be used in the mass production of the catalytic
converter canister. Six welders are required for full-volume production and
the total lead time for this equipment is 24 months. General Motors states
that in order for this equipment to be available for 1975 model year production
purchase orders must be placed by July 1, 1972. Production welding experience
is lacking for the new corrosion-resistant steel used for the canister and new
welding techniques must be tested and evaluated. With regard to other com-
ponents in the proposed 1975 emission control system--such as the carburetor,
electronic ignition, and quick heat manifold--the lead time is paced by capital
equipment acquisition and the period required for field tests. Lead time for
these components is not critical (Ref. 11-4).
11. 3 AUTOMOBILE MANUFACTURERS' SCHEDULES FOR
CATALYTIC CONVERTERS
Since the catalytic converter appears to be a pacing production development
item with which all of the manufacturers must contend, it serves as a con-
sistent basis for examining and comparing production schedules and lead times
11-4
-------
among the different manufacturers. The data available for this comparison
are shown in Figure 11-1.
In general, the agreement in the catalytic converter production milestones
among the various manufacturers is good. Exact agreement between Ford
and American Motors Milestone C, facilities contract, is noted; both manu-
facturers reference this milestone to the Engelhard facilities development.
Among all the manufacturers represented, the overall lead time requirement
ranges from 25 to 28 months.
The schedules shown for the two foreign manufacturers are referenced to a
decision date for selecting the type of converter to be used in their 1975
systems. This date appears to be a couple of months downstream from the
equivalent decision point for the domestic manufacturers. The reason for this
is not known; however, the difference is not significant.
11.4 CATALYST SUPPLIERS' SCHEDULES
Schedules submitted in the suspension request hearings by the catalyst sup-
pliers are shown in Figure 11-2 in comparison with the Figure 11-1 suppliers'
schedule submitted by Ford. The corresponding sets of data from these two
figures are found to be in agreement. If the lead time reference point is fixed
at the date of firm commitment, it is seen that the lead times estimated to be
required by the various catalyst suppliers vary in a narrow range from 21 to
25 months. The differences in lead time may be due to varying degrees of
optimism in estimating the facility construction and equipments schedule.
From Figure 11-2, and allowing for the fact that production.catalysts must be
available at the manufacturer's plant in advance of first vehicle production,
the automotive manufacturers' lead time requirement would be expected to be
approximately 2 years. This is consistent with the Ford lead time
requirement shown in Figure 11-1 as 28 months. Since the schedules
of the automotive manufacturers are in good general agreement, it is
11-5
-------
AMERICAN MOTORS
CHRYSLER
FORD
GENERAL MOTORS
VOLVO
VOLKSWAGEN
CY
246
72 tt
8 10 12 2 4 6
C
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8 10 12 2 4 68
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^LEAD TIME REFERENCE POINT
ABC D E F
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30
25 20 15 10 5
MONTHS TO VEHICLE PRODUCTION
A
B
C
PRODUCTION DESIGN PRELIMINARY
APPROVAL
TOOLING AND FACILITIES
PROGRAM APPROVAL
FACILITIES AND LONG LEAD TIME
PARTS/EQUIPMENT CONTRACT
D - START DURABILITY AND
CERTIFICATION TESTS
E - START VEHICLE PILOT PART
PROGRAM
F - START VEHICLE PRODUCTION
Figure 11-i. Significant Milestones for Catalytic Converter Production
(Data Supplied by Automobile Manufacturers)
-------
ENGLEHARD
PLANT No. 1
PLANT No. 2
OXY-CATALYST
MATTHEY BISHOP
W.R. GRACE
MONSANTO
UOP
CY 71
8 I 10 I 12
CY 72
8 10 12
CY 73
6 I 8 I 10 I 12
CY 74
8 10
V25 mo)
S(24 mo)
^(24 mo)
RESEARCH, DESIGN, DEVELOPMENT
PROGRAM APPROVAL PERIOD (commitment agreements,
product specification definition, etc)
PLANT SITE SELECTION, DESIGN, CONSTRUCTION
EQUIPMENT DESIGN, CONSTRUCTION, DELIVERY, INSTALLATION
PLANT START UP, SHAKEDOWN
FULL PRODUCTION
* REQUIRED COMMITMENT DATE FROM AUTOMOBILE MANUFACTURERS
<2> POSSIBLE SLIPPED COMMITMENT DATES (cost increase)
Figure H-2.^ Representative Catalyst Production Lead Time Schedules .
-------
concluded that there are no gross inconsistencies among or between the lead
time specifications of the suppliers and manufacturers.
11.5 CONTRACTUAL COMMITMENTS WITH SUPPLIERS
The Ford/Engelhard relationship represents the only case to date of a
contractual commitment between an automobile manufacturer and a catalyst
supplier. Ford has contracted with Engelhard Industries for supplying cata-
lysts to be used in its emission control system and has provided financial
backing of up to $4. 9 million for facilities and equipment. Ford is also con-
sidering other sources of supply but no other contracts have been initiated to
date. Other automobile manufacturers are also evaluating multiple sources
of supply for catalysts but have not made contractual commitments as yet.
11.6 SCHEDULE INTEGRATION
An example of the integration of a supplier schedule with that of an automobile
manufacturer is shown in Figure 11-3 for the Ford/catalyst supplier relation-
ship. The Ford production milestone schedule taken from Figure 11-1 is
compared in Figure 11-3 with the Engelhard Plant #2 facility construction
program and with the construction program for other catalyst platers and for
substrate suppliers.
Milestone C in the Ford schedule represents the supplier facilities contract
award and this may be seen to correspond -with the initiation of construction in
the Engelhard schedule. The build up to full production in the Engelhard
schedule corresponds to the Ford milestone for the completion of the production
sample build, immediately preceding milestone E, which is the start of vehicle
pilot production. At this point, the supplier's production output must be
available for Ford's pilot assembly operation.
Ford is negotiating with other catalyst platers, and their schedules for plant
construction, tooling and production corresponds well with the Engelhard
schedule.
11-8
-------
FORD
CATALYST PLATER
SITE SELECTION
SITE PROCUREMENT
CONSTRUCTION
ENGLEHARD PLANT No. 2
TOOLING AND FIXTURES
PRODUCTION
OTHER CATALYST PLATERS
MATTHEY-BISHOP
Un P
. \j*
W.R. GRACE
SUBSTRATE SUPPLIERS
/% IVIbK 1 w AIN LAVA
2
4
CY
6
AB
1
72
8
C
1
10
12
2
4
CY
6
73
8
I
10
3
12
CY 74
2
k
4
6
E F
1
\
-
-
-
x.
Figure 11-3. Catalytic Converter Program Timing (Ford)"
-------
For the substrate construction. Ford has made purchase commitments with
American Lava, and may presently be making commitments to another
substrate supplier. The timing for the development of these supplier facilities
is about 24 months, or approximately the same as for the Engelhard facility
development.
In general, the scheduling duration seems to be consistent between the
manufacturer and the suppliers.
11.7 SCHEDULE COMPRESSION AND COST INTERACTIONS
All manufacturers have indicated that their current schedules represent an
accelerated work effort in order to develop production facilities in time for
the 1975 model year. An example of this schedule compression is given by
Chrysler (Figure 11-4). A reduction of one full year in lead time is shown;
this appears to have been accomplished mainly through a delay in the start of
the production design and test phase and an increase in the overlap of this
phase with other work efforts. Notable is the lack of schedule change in the
design release phase.
Additional schedule compression holds higher risks for the automobile
manufacturer because of major reductions in the time allowance for correcting
problems in production hardware design or assembly line operations; this effect
is only correctable to a degree through the use of labor on overtime which
in turn raises product cost. Some compression is afforded if the original
program goals are revised. Ford estimated an added gain of 3 to 3-1/2 months
over its accelerated schedule if its proposed interim emission standards were
adopted (see Figure 11-5).
Some catalyst suppliers have estimated an ability to further compress their
schedules by 3 to 6 months (Figure 11-2) but with corresponding increases in
unit costs from approximately 3 to 12 percent. At this time there is insufficient
information to accurately correlate the increase in unit cost with schedule
compression for either catalyst or automobile manufacturers.
11-10
-------
DEVELOPMENT AND £
TEST
PRODUCTION DESIGN
AND TEST
LONG-LEAD TOOL
COMMITMENT
DESIGN RELEASE
CERTIFICATION
PILOT PRODUCTION
CY 70
246 81012
LEAD TIME*
REFERENCE
CY 71
2468 1012
_J
L
POINT 4
CY 72
246 81012
^pllll
CY 73
2468 10J12
JL_
mmmmlm*
H
r
CY 74
2468 1012
ill
NORMAL
ACCELERATED
Figure 11-4. Comparison of Chrysler Production Design Schedules
(1975 Emission Control System)
-------
START 50,000-mi DURABILITY TESTING
ACCELERATED SCHEDULE
FORD ENGINE EMISSION PROGRAM
TIMING PLAN*
ACCELERATED HIGH RISK SCHEDULE
FORD ENGINE EMISSION PROGRAM*
(assumes adoption of interim standards)
* Suspension request, Exhibit 4-8 (a)
ENGINEERING RESEARCH
£*? Xi* *
DESIGN/DEVELOPMENT
PROGRAM APPROVAL
PRODUCTION ENGINEERING
I i i i i i 1 i i i i i I i i i i i I i i i i
48 36 24 12
MONTHS TO VEHICLE PROUCTION
.1
TOOL CONSTRUCTION AND
TRYOUT
PILOT ASSEMBLY
PRODUCTION BUILDUP
Figure 11-5. Accelerated Development Schedules
-------
REFERENCES
11-1 American Motors Corporation, Letter to Mr. William D. Ruckelshaus,
Administrator, Environmental Protection Agency, 4 April 1972.
11-2 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the
Clean Air Act," March 1972.
11-3 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II,
5 April 1972.
11-4 General Motors Corporation, "Request for Suspension of 1975 Federal
Emissions Standards," Volumes I and II, 3 April 1972.
11-13
-------
12. UNCONVENTIONAL, AUTOMOTIVE ENGINES
Unconventional automotive engines are those other than the reciprocating
spark ignition internal combustion engine. They include the Wankel, diesel,
gas turbine, stratified charge, Rankine, and Stirling engine classes. The
following sections briefly describe the salient features of each engine type
and summarize the status of the automotive industry development efforts.
12. 1 WANKEL (ROTARY) ENGINE
The Wankel engine, although in the spark ignition internal combustion class,
is entirely different mechanically from the conventional reciprocating engine.
InStead of reciprocating pistons and valves, this engine contains one or more
triangular-shaped rotors which rotate on an eccentric shaft in a rotor housing.
The volume between the rotor and the housing varies as the rotor turns to
first achieve compression of the air/fuel mixture and then expansion of the
products of combustion.
Compared with the conventional reciprocating engine, the Wankel is smaller
in weight and volume for the same power, has very low levels of vibration
since there are no reciprocating masses, and can run on very low octane
number fuels; its untreated exhaust contains somewhat more HC, approxi-
mately the same CO, and much less NO ; its cost in large volume production
Jf,
is expected to be less, and its fuel economy the same or poorer, depending
on the particular design.
12.1.1 Ford
Ford's Wankel engine program includes both dynamometer and vehicle
phases (Ref. 12-1). The dynamometer phase is concerned with optimization
of a Ford-designed Wankel engine and additional emission control system
components. The current vehicle phase is concerned with evaluation of a
Mazda RX-2 vehicle (Toyo Kogyo Wankel engine) equipped with Ford emission
12-1
-------
control devices. The best emission results obtained by Ford on a carefully
timed Mazda rotary engine vehicle are 1. 3 gm/mi HC, 24 gm/mi CO and
0. 66 gm/mi (1975 test procedure).
Ford believes that a thermal reactor, a catalytic converter, and exhaust gas
recirculation will have to be used with the Wankel engine to meet 1975-76
emission standards. Results from the Mazda test vehicle are expected from
the Riverside test facility in late 1972; test results from a vehicle incorporating
a Ford-designed Wankel are expected in mid-1973.
If the development program is successful, Ford estimates that it would then
require at least 42 additional months to begin production of the engine.
12.1.2 General Motors
General Motors has conducted an intensive study and development program
on the rotary combustion Wankel engine for two years (Ref. 12-2). Base
engine emissions for the General Motors Wankel engine are somewhat higher
in HC, about the same in CO, and slightly lower in NO than the conventional
Jt
G. M. reciprocating engines. Hence, both thermal reactors and catalytic
converters have been applied to the rotary engine. Possible advantages of
the Wankel are visualized to be primarily in the areas of reduced size and
weight, which could permit the utilization of some emission control systems
not suited to the conventional engine (e. g. , a large thermal reactor).
The 1975 standards have been achieved at low mileage (by a small margin)
with a Wankel-powered 2500-lb vehicle incorporating air injection in the
exhaust manifold and a monolithic noble metal catalyst (no EGR). The
manufacturer believes that the durability problems of the catalyst will be
similar to those encountered with conventional engines.
12-2
-------
General Motors has not been able to achieve the 1975 standards with a thermal
reactor alone; the best single test was marginal on HC, over on CO, and
consistently below 1 gm/mi on NO . General Motors states they suspect that
the reason that they were not able to make the 1975 standards at low mileage
with the thermal reactor alone, while Toyo Kogyo did accomplish this, is
that the fuel economy of its Wankel engine is similar to that of conventional
reciprocating engines while the Toyo Kogyo Wankel was 25 to 30 percent
poorer. General Motors NO test results tend to belie this contention as
Ji
they were consistently in the 0. 5 to 0. 7 gm/mi range; these satisfactory
NO emission results were attributed to running rich to obtain good per-
formance from the thermal reactor.
General Motors states they cannot produce Wankel engines for 1975 model year
cars, except on a very limited basis.
12.1.3 Daimler-Benz
The Daimler-Benz Wankel engine is in a predevelopment state (Ref. 12-3). It
has been installed in a vehicle with an emission control system consisting of a
monolithic oxidation catalyst, EGR, air injection, and retarded ignition.
Emission test results (gm/mi) are 0. 34 for HC, 2. 49 for CO, and 1. 24 for
NO (averages of 21 tests).
3t
Daimler-Benz states that production of Wankel engines for model years
1975-76 is not possible.
12. 1.4 Toyo Kogyo
Toyo Kogyo presently produces rotary-engined cars at a low-production rate
(15, 000 cars/month versus 25,000 cars/day for General Motors) (Ref. 12-4).
This company has met the 1975 standards at low mileage with a 2750-lb
vehicle equipped with a 70-CID two-rotor Wankel and a thermal reactor (no
12-3
-------
EGR). Emission results (in grams per mile) were 0. 17 for HC, 2. 2 for
CO, and 0.93 for NO (averages of 18 tests). These values satisfy Toyo
Ji
Kogyo engineering low mileage goals.
Toyo Kogyo has not demonstrated 50, 000-mile durability but is optimistic
about this performance capacity. Equivalent engine dynamometer tests have
successfully been completed; the thermal reactor used is very similar to the
one now on its 1972 rotary engine cars. The Toyo Kogyo thermal reactor is
unique from that developed by other manufacturers in that it is force cooled
by air from the secondary air pump which results in relatively low reactor
material temperatures and low heat rejection to the engine compartment.
Emission performance for the 1975 prototype system was improved over the
1972 system by carburetor and ignition system modifications and modulation
of the secondary air system. These changes resulted in sizable emission
performance improvements during the engine warm-up portions of the emission
tests (Ref. 12-5).
Toyo Kogyo's projected 1975 car has a fuel economy loss of five percent
compared to their 1972 model. However, Ford and General Motors claim
their 1972 small economy cars (e.g. , Vega, Pinto, etc. ) have 25 to
30 percent better fuel economy than the Toyo Kogyo 1972 rotary engine
vehicles.
The maximum production rate estimated by Toyo Kogyo for 1975 is 50, 000
to 70, 000 cars per month.
12.2 DIESEL, ENGINE
The diesel engine, widely used in heavy-duty vehicles (trucks, buses, etc. ),
has the potential for low emissions without aftertreatment of its exhaust. Test
procedures for light-duty diesel-powered vehicles have not been firmly
established. However, on the basis of anticipated procedures and current test
results, it appears that the 1975 standards are achievable without exhaust
treatment by the Mercedes 220D vehicle (Ref. 12-3).
12-4
-------
The diesel achieves low HC and CO emissions by operating at high
compression ratios and very lean air/fuel ratios. However, operation in the
lean air/fuel ratio regime precludes utilization of a NO catalyst, which
requires a reducing atmosphere. Tests with the only other alternate methods
of reducing NO emissions, e. g. , EGR and retarded injection, to date indicate
Ji
the 1976 standards are not achievable by a diesel.
The high compression ratio and lean air/fuel ratio of the diesel result in its
being a very large and heavy engine. Daimler-Benz indicates that the size and
weight problem may be so acute that it is impossible to build a diesel-powered
car with sufficient power to meet the passing requirement of the DOT safety
car (Ref. 12-6).
Initial cost of the diesel is more than for a conventional reciprocating
gasoline engine of the same power. Daimler-Benz has indicated an increased
cost of $1500 for the diesel over the gasoline engine (120-horsepower engines).
Daimler-Benz presently sells a 62-horsepower diesel car which is economically
attractive for some markets where its fuel economy and long life are important
(e. g. , high mileage commercial uses where gasoline prices and horsepower
taxes are very high (Ref. 12-6)).
No other automobile manufacturers foresee the diesel as an attractive approach
to meeting the 1975-76 standards. Their expressed reasons are essentially the
same as discussed above, plus a concern for the diesel1 s distinctive exhaust
odor.
12. 3 GAS TURBINE
12. 3. 1 General
The gas turbine operates at very lean air/fuel ratios with correspondingly low
maximum temperatures in the engine as compared with a reciprocating
engine. Hence, the HC and CO emissions of the engine are low. It is
12-5
-------
hoped that no aftertreatment devices will be necessary. Chrysler states
that its engine would meet the 1975 standards. To date no automobile manu-
facturer has succeeded in meeting the 1976 NO standards, although some
are encouraged by their test results.
Ford, General Motors, and Chrysler all have passenger car gas turbine
programs. In addition to the emission problems discussed above, they indi-
cate other problems, including: (a) high cost, (b) poor fuel economy at part-
load, (c) requirement for large quantities of nickel, and (d) poor acceleration
characteristics (Refs. 12-1, 12-2, 12-7).
All manufacturers indicate that sizable production is not possible until the
1980s.
12.4 STRATIFIED CHARGE ENGINE
12.4. 1 General
The term "stratified charge" characterizes the most significant difference
between this type of engine and the conventional reciprocating internal com-
bustion engine. At the commencement of combustion, the air/fuel mixture
is not homogeneous but purposely made locally richer (or "stratified") near
the spark plug. Improved fuel economy and possible multifuel use were the
original reasons for interest in this type of engine.
The engine may permit the achievement of low NO emissions without an NO
, -X Jt
catalyst and with relatively satisfactory fuel economy. This is possible
because the local richness permits higher EGR rates without misfire for the
same engine air/fuel ratio and results in reduced peak combustion tempera-
tures. A thermal reactor and/or catalytic converter will be necessary for
HC/CO emission reduction. Hence, this engine is of interest primarily for
1976 standards since the 1975 NO standard can be met with a conventional
reciprocating engine.
12-6
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12.4.2 Ford
Ford has built and tested a 141-CID engine in an M-151 MUTT (army vehicle
of 3000-lb gross weight (Ref. 12-1)). The engine design also has been
adapted to a 141-CID Capri engine and to a 351-CID V-8 engine for a Torino.
Emission results (in grams per mile) from the MUTT program are:
HC CO NO
Average of 14 EPA tests 0.37 0.93 0.33
Average of 4 Ford tests 0.34 1.01 0.35
It should be noted that the test vehicle was unable to follow the CVS acceleration
schedule because of insufficient power. Such reduced acceleration also normally
would reduce NO emissions from a conventional engine.
Ji
The major problems encountered with this type of engine at the present time
include the following:
a. A production-feasible design for the injector is not available.
b. Engine operation still encounters misfire at high EGR rates.
c. Durability of some engine components (such as spark plugs )
is questionable.
d. The HC/CO catalyst durability problems of the conventional
engine also must be solved.
Ford estimates the earliest possible date for limited production is 1979.
12.4.3 General Motors
General Motors has conducted tests on a prechamber variation similar to that
tested at the University of Wisconsin by H. K. Newhall, et al. The General
Motors engine is in a very early state of development (Ref. 12-2).
12-7
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12.4.4 Chrysler
In late 1970, Chrysler entered into an agreement with Texaco to evaluate
Texaco's stratified charge engine (Ref. 12-7). Chrysler is adding HC/CO
catalysts and EGR to two Texaco engines which will be installed in Cricket
vehicles for testing. Chrysler is also designing a V-8 stratified charge
engine for a normal-size passenger car.
12.5 RANKINE ENGINE
In the Rankine engine system, combustion takes place in an external burner,
and heat is then added to the working fluid in a boiler. The external burner
can operate at lean air/fuel ratio if desired and, similar to the gas turbine,
has potential for low emissions without aftertreatment of the exhaust.
12.5.1 Ford
Ford entered into an agreement in 1970 with Thermo-Electron Company for
a joint development program on Rankine cycle engines for automotive use
(Ref. 12-1). As part of this effort, emissions have been measured from a
full-size burner and simulated boiler operated on a simulated CVS-CH test.
The results obtained were (in grams per mile):
HC CO NO..
^-^^ -^ ^^^_^£L.
0.13 0.19 0.26
These emissions are based on the projected flow rates required by the engine
to operate over the Federal driving cycle.
Many problems remain to be overcome, however, before this concept could
possibly be introduced into production. These problems include condenser
size, safety aspects, cost, controls, and engine cooling.
Ford's assessment is that unless technological breakthroughs are made, the
engine is too complex and costly for widespread automotive application.
12-8
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12.5.2 General Motors
General Motors has built and tested steam cars and is continuing work in the
field (Ref. 12-2). It also concludes that a technological breakthrough is
necessary for this type of engine to become attractive for use in passenger
cars.
12.5.3 Chrysler
Past studies by Chrysler have led to a negative view toward the Rankine type
of power plant for automotive use for the same types of reasons discussed above
(Ref. 12-7), However, recent developments have encouraged Chrysler to
reassess its position. It has entered into an agreement with Steam Engine
Systems, Inc. , to install a Rankine engine in a production vehicle. This is a
long-term program, however, and production, if it were to occur, would be
many years away.
12.6 STIRLING ENGINE
The Stirling engine cycle -which is based on the alternate heating and cooling
of an entrapped gas volume is a very efficient cycle. Its combustor is an
external combustor and hence has the same potential for low emissions as
exists for the Rankine cycle engine. Further emission reduction might be
possible by means of a trade-off between fuel economy and emissions.
12.6.1 Ford
In August 1971 Ford entered into a technical exchange agreement with Philips
of Holland who has been the most important developer of Stirling engines.
Philips' calculations, based on tests with small engines, indicate this type
of engine has the potential for meeting 1976 standards (Ref. 12-1).
Recently completed packaging studies by Ford indicate the major problem is
large radiator size. Other unresolved problem areas are safety (hydrogen
working fluid), cost, and complexity.
12-9
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Earliest possible production date is estimated to be 1980.
12. 6. 2 General Motors
General Motors has designed and built a Stirling engine car (Ref. 12-2).
The HC and CO emissions were low, but NO emissions were high. General
j£
Motors believes this engine is too heavy, complex, and expensive for automo-
tive use.
12-10
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REFERENCES
12-1 Ford Motor Company, "Application for Suspension of 1975 Motor
Vehicle Exhaust Emissions Standards, " Volumes I and II,
5 April 1972.
12-2 General Motors Corporation, "Request for Suspension of 1975
Federal Emissions Standards, " Volumes I and II, 3 April 1972.
12-3 Daimler-Benz, "Statement of Daimler-Benz AG before the Environ-
mental Protection Agency, Washington, D. C.," April 1972.
12-4 Toyo Kogyo Company, Ltd. , Transcript of Proceedings -- Auto
Emissions Extension -- Environmental Protection Agency,
Washington, D. C. , 21 April 1972.
12-5 Toyo Kogyo Company, Ltd. , "Statement of Toyo Kogyo Company,
Ltd.," April 1972.
12-6 Mercedes-Benz Company (Daimler-Benz AG), Transcript of
Proceedings -- Auto Emissions Extension -- Environmental
Protection Agency, Washington, D. C. , 19 April 1972.
12-7 Chrysler Corporation, "Application for Suspension of 1975 Motor
Vehicle Emission Standards Pursuant to Section 202(b)(5) of the
Clean Air Act, " March 1972.
12-11
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APPENDIX: NONAUTOMOTIVE INDUSTRY TESTIMONY
This appendix is made up of the highlights of the statements made at the
EPA Suspension Request Hearings held on April 10-28, 1972 in Washington,
D. C. , by witnesses that are not part of the automobile industry.
Mr. Rudich
Mr. David A. Rudich is the President of Enviro Plan, a consulting engineering
firm involved in a broad spectrum of environmental quality and natural
resource management activities which also include automotive emission
control. His testimony was specifically directed at technology development
within the field of internal combustion engines. These are the significant
points in his testimony:
a. The "proper" approach to the control of emissions is by
cleaning up the combustion process; not by cleaning up the
products from combustion.
b. Enviro Plan has a theoretical design which has promise to
meet the 1975-76 requirements and can be applied to
current internal combustion engines.
c. Enviro Plan does not have the financial resources to pursue
the hardware development and has been unable to stimulate
anv interest from the automobile industry.
Ms. Leavitt
Ms. Helen Leavitt, author, contends that the automobile is technologically
outmoded and should be replaced by public transportation systems. Her
position is that the denial of the suspension requests will bring about the
recognition of the automobile limitations and result in an earlier diversifi-
cation of interest by the automobile manufacturers. She envisions that this
diversification would include the development of public transportation systems.
Mr. Pancoe
Mr. Arthur Pancoe is the director of the Society Against Violence to
Environment (SAVE) and Citizens Action Program in Chicago (CAP). His
A-l
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basic points are (I) do what can be done now, (2) cost of emission controls
and replacements should not be a consideration, and (3) people have the
right to clean air.
Baaed on hie judgme^t'Qjf ,the available technology, he recommends that th«
requirements be red.ucefij'to 85 percent of the 1975 standards.
Ms. Reid
Ms. Barbara Reid, Washington representative of Environmental Policy
Center, attacks most of'the issues involved with quotatiqrjS; from the hearings
! i ' ' ' '- i "i .
and reference data which support the denial of the suspension request. Her
I i ' ('''! I '
major concern, which was discussed in much length during the; panel
questioning, was the averaging concept in the acceptance of production line
vehicles. She contends that it should not be allowed on the ibasi's that it is
not consistent with the intent of the Clean Air Act and does not serve the
interest of the automobile purchaser.
Mr. Clapper
Mr. Louis S. Clapper, Director of Conservation for the National Wildlife
Federation, contends that the suspension cannot be considered as "essential
to the public interest or the public health and welfare of the United States. "
He did not address the other issues which bear on this determination.
He recommends that people buy less powerful cars. This is based on his
opinion that smaller cars produce less emissions.
Mr. Chou
Mr. Hsiao Ta Chou, mechanical engineer, states that the solution to the
automobile engine emissions lies in achieving complete combustion in the
engine by precise control of the air/fuel mixture and that he has developed
a technology for the determination of the instantaneous value of the true
fuel mass flow rate for controlling the exact mixture under all conditions.
His complaint is that while he has the solution, he cannot interest anyone
in using his technology.
A-2
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David G. Hawkins
Mr. Hawkins is an attorney with the National Resources Defense Council.
It was Mr. Hawkins1 opinion that:
a. There has been no demonstration that a suspension is
essential to the public interest.
b. None of the applicants has established that he has made
all good faith efforts to comply with the standards.
c. It has not been established that the technology is not
available to meet the standards.
Accordingly, Mr. Hawkins offered the following proposal to EPA. Concurrent
with the denial of the requests, the Administrator should request from
Congress an emission tax on automobiles which do not meet the 1975 stan-
dards. The tax would be applicable to the cars of any manufacturer who in
the future requested and was granted a suspension of the standards. The
amount of the tax would be keyed to the level of the interim standards set at
the time of suspension. The higher the interim standard, the higher the tax.
Individual manufacturers would also be permitted to request certification of
their vehicles at levels more stringent than the interim standard in return
for a proportional tax reduction.
Clarence M. Ditlow
Mr. Ditlow represented the Public Interest Research Group, Washington,
D. C. It was his opinion that a one-year suspension is not essential to the
public health and welfare of the United States. He stated that the extent and
direction of emission control research and development by the motor vehicle
manufacturers preclude the finding of any good faith attempt to meet the
1975 vehicle emission standards.
It was Mr. Ditlow1 s recommendation that the suspension requests be denied
and that EPA should recommend that Congress enact legislation setting an
interim standard (unspecified) and requiring retrofitting of all pre-1968 light
duty motor vehicles with emission control technology sufficient to lower
A-3
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total emissions from all motor vehicles to at least the levels attainable if
the 1975 light duty vehicle emission standards were in effect.
J. Wagshal, M. P. Walsh, F. C. Hart, J. L. Rankin, D. Shapiro
This group appeared before the panel on behalf of 4 cities and 21 states in
opposition to the granting of any suspension to the 1975 standards. It was
their contention that under the law, as defined by the Clean Air Act, the
applicants had not demonstrated that it was in the public interest or welfare
to grant a suspension, that a good faith effort had not been made, and that
it had not been shown that the technology was not available. They also
expressed the opinion that the National Academy of Sciences report had
become obsolete in view of the progress which had been made since it had
been published and in view of the evidence presented at the hearings.
Louis B. Lombardo
Mr. Lombardo is currently forming an organization known as the Public
Interest Campaign. It was his opinion that the suspension request should be
denied on the basis that (1) it was not in the best interest of the United
States to grant a suspension; ;(r2) a good faith effort has not been demonstrated
by the auto manufacturers; (3) the applicants have not demonstrated that the
technology is not available; and (4) in his opinion, the National Academy of
Sciences report indicates that technology is available to meet the standards.
Mr. Lombardo also requested that EPA subpoena manufacturers of fuel
injection systems (e.g. , American Bosch and Bendix) to obtain further
information on the capabilities of fuel injection systems to meet the 1975
standards.
Robert J. Rauch
Mr. Rauch is assistant Legislative Director of Friends of the Earth. The
initial portion of his testimony dealt with a discussion of the credibility of
the auto manufacturers' claim that the converters they have tested cannot
A-4
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come close to meeting the 50, 000 mile standard whereas the converter
manufacturers have testified that the standards can be met. It was
Mr. Rauch's opinion that the catalyst manufacturers stand to lose more
than the auto manufacturers if the catalytic converters do not meet the 1975
standards, and that the testimony of the catalyst manufacturers is, therefore,
more credible.
Mr. Rauch also discussed the legal and moral pros and cons of granting the
extension and, in conclusion, recommended that the request for suspension
be denied since, in his opinion, the testimony of the catalyst manufacturers
alone casts sufficient doubt that meeting the 1975 standards is technologically
infeasible.
I. Walton Bader
Mr. Bader is a trustee of the Heart Disease Research Foundation which is
engaged in research activities directed toward the reduction of heart and
lung ailments.
Mr. Bader's testimony consisted primarily of the following statement.
The Heart Disease Research Foundation has determined that a correlation
exists between the increase of heart and respiratory ailments and the
increase of pollution in the metropolitan areas. The Foundation's position
is that the automobile is the primary cause of pollution in most metropolitan
areas. Therefore, it opposes the request by the automobile manufacturers
for a one-year extension to the 1975 standards.
William D. Balgord
Mr. Balgord represented the New York State Department of Environmental
Conservation. This organization, in cooperation with the New York City
Department of Air Resources, has completed two years of a three-year
research effort to develop catalytic emission control systems independent of
the auto manufactureres. Its objective is to demonstrate the technical and
A-5
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economic feasibility of these systems in relation to the 1975 standards.
The effort has been focused on reducing NO , with no effort being made to
.develop HC/CO oxidizing catalysts. Testing to date has been conducted on
a bench-mounted V-8 engine operated over a simulated durability driving
cycle. Commercially available unleaded fuel has been used for all tests.
The most promising NO reducing catalysts appear to be a base-metal
A.
catalyst mounted on a honeycomb substrate. Preliminary results indicate
a potential for greater than 99 percent reduction of NO in a two-catalyst
Ji
converter system which also controls HC and CO (no details were presented
of the oxidizing catalyst).
J. Howard Flint
Mr. Flint is counsel for the Pancoastal-PXP Corporation, Hartford,
Connecticut. Mr. Flint presented brief verbal testimony together with
written and film documentation regarding the Corporation's findings on the
Pritchard steam-driven automobile being developed in Australia. No
specific details were provided in the verbal testimony other than the general
statement that this vehicle, without a catalytic converter, meets the 1975
standards and exceed the 1976 NO standard by approximately 0.2 percent.
.X
Meeting the 1976 NO requirement does not present any problem to the
jt
Pritchard Co. , according to Mr. Flint.
Department of Air Resources, New York City
Testimony on behalf of the New York City Department of Air Resources was
presented by Mr. Fred C. Hart, Commissioner, Department of Air
Resources; Mr. Michael P. Walsh, Director, Bureau of Motor Vehicle
Pollution Control; and Mr. Jerome Wagshal, Special Counsel to the City
of New York. The primary purpose of their testimony was to report the
results to date of a program to evaluate the potential of an Engelhard PTX-5
catalytic converter as a retrofit device for light duty vehicles in urban
service.
A-6
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The test fleet used in this program consisted of six police cars, four
assigned as patrol vehicles and two as inspector vehicles. One of the patrol
vehicles was not equipped with the retrofit devices and served as* the base-
line control vehicle. All vehicles were 1971 6-cylinder, 225-CID Plymouth
Furys with automatic transmission.
Five of the vehicles were equipped with an Engelhard PTX-5 noble metal
catalyst and secondary air injection between the exhaust manifold and the
catalytic converter. No NO control was attempted nor was an overtempera-
ture protection system used. All six test vehicles were equipped with
electronic ignition systems.
The fuel used was commercially available Amoco Super Premium gasoline
with a Research Octane No. of 100.3. A random sampling of the amount of
lead in the fuel showed, for the most part, 0. 01 gm/gal or less although
one sample was found to contain approximately 0. 1 gm/gal while another
was 1. 0 gm/gal. This "contamination" was believed to be the expected
variation that might be encountered with the normal distribution of various
grades of fuel. No attempt was made to correlate the lead content of the
fuel with any observed deterioration in the catalyst efficiencies.
All vehicles were tuned to the manufacturer's recommended specifications at
the start of the test. Subsequent maintenance was performed according to
standard Police Department procedures and consisted of an oil change and
new oil filter every 4, 000 miles. Spark plugs were checked every 6, 000
miles and replaced as necessary.
The driving pattern experienced by the four patrol vehicles (including the
control vehicle) was described as a combination of extensive periods at
idle as well as substantial amounts of high-speed driving. These cars were
in 24-hour per day operation and accumulated 3500-4500 miles per month.
The inspector vehicles experienced what was described as reasonably normal
driving and accumulated mileage at the rate of 1,000-1,500 miles per month.
A-7
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No overheating of the catalytic converters was experienced and although
specific data were not obtained, no overt evidence of an increase in fuel
consumption or any decrease in performance was observed.
All emission tests were performed in accordance with the 1972 CVS test
procedure approximately every 4,000 miles. Emission results are shown
in Table A-1. Although these vehicles do not meet the 1975 standards, a
significant reduction in the HC/CO emission levels was achieved with what
seems to be a comparatively unsophisticated emission control system.
An additional program is being initiated using Engelhard, UOP, and Oxy-
Catalyst to retrofit a small fleet of heavy duty sanitation trucks. It is
planned to have 15 vehicles converted by May 1972.
Based upon the results achieved from the retrofit program, it was concluded
by Mr. Walsh that it should be possible to meet the 1975 standards by
controlling the catalyst temperature, the choke mechanism, and the amount
of oxygen injected into the converter.
Richard S. Morse
Mr. Morse is a senior Professor at the Sloan School of Management,
Massachusetts Institute of Technology. He also is Chairman of the Board
of the Steam Engine Systems Corporation which has a contract with EPA
to build a steam automobile power plant. The emissions from the burner of
this power plant were reported to be 0.09 gm/mi HC, 0.60 gm/mi CO, and
0. 16 gm/mi NO . The test procedure under which these results were
obtained was not specified.
It was Mr. Morse's opinion that short of a wartime-type crash program, it
would be very difficult to mass produce a steam powered vehicle by 1975
and would probably take three years even on a crash basis.
A-8
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Table A-l. New York City Light-Duty Vehicle Retrofit Program
Cata-
Veh. Actual lyst
No. Date Miles Miles
378 10/15/71 3,899 Before
12/14/71 6,026 1.028
01/02/72 7,292 2,294
03/08/72 12,357 7,359
Conversion: 4,998 mi - 152 hr
476 10/15/71 3,119 Before
11/18/71 4,457 7
12/16/71 4,952 502
01/13/72 6,058 1,608
03/09/72 7,632 3,182
Conversion: 4,450 mi - 143 hr
1128 10/08/71 6,552
12/10/71 14,460
01/19/72 18,892
02/17/72 20,815
03/23/72 23,831
Control
1693 10/07/71 15,860 Before
10/12/71 15,892 0
10/14/71 15,902 10
11/24/71 21,147 5,255
12/08/71 23,110 7,218
01/20/72 28,561 12,669
02/16/72 32,361 16,750
03/24/72 35,834 19,942
Conversion: 15,892 mi - 708.2 hr
1866b 10/08/71 6,758 Before
10/14/71 6,836 3
10/29/71 8,456 1,623
11/24/71 12,352 5,519
12/22/71 15,234 8,401
01/06/72 17,806 10,973
02/17/72 22,122 15,289
Conversion: 6,833 mi - 710 hr
2351 10/08/71 6.534 Before
12/09/71 14,979 2,657
01/07/72 18,377 6,055
02/10/72 22,816 10,496
03/22/72 29,786 17.464
Conversion: 12,322 mi - 1212 hr
a!972 Federal test procedure
Meter
Hours
98
199.7
256.2
555. 1
67
143.5
168
223. 1
302. 1
..
--
..
--
705
708.2
718.2
1205
1396
1904.9
2294.6
2264.4
704
710
909
1331
1655
1944
2630. 1
487
1437
1820
2414.3
3208
Cata-
lyst
Hours
Before
47.7
112.2
403. 1
Before
0.5
25
80. 1
159. 1
--
--
..
--
Before
0
1
496.8
687.8
1196.7
1586.4
1956.2
Before
0
199
621
945
1234
1920.1
Before
225
608
1203.3
1996
Emissions, gm/mi
CO
54.8
12.9
14.0
17.8
76.3
9.2
3.3
3.6
5.0
51.3
41.0
45.2
48.8
50.7
47.5
20.1
13.7
15.2
20.6
12.5
14.7
12.0
55.8
13.6
3.0
6.9
10.9
16.4
17.4
51.7
18.7
20.4
18.3
17.8
HC
5.36
0.86
1. 10
1.17
7.47
0.95
0.56
0.57
0.45
6.49
2.41
2.20
2.38
5.01
4.55
1.61
1.86
0.94
0.88
0.93
1.08
1.75
5.46
1.44
0.47
0.83
1.06
1.72
1.61
5.36
1.04
1.11
1.48
2.35
NO
X
_ _
6.19
7.39
7.77
2.40
5.34
5.62
5.52
_ _
3.82
5.99
4.37
3.67
..
--
--
6.87
--
6.94
7.47
3.59
--
4.33
4.78
4.97
7.99
- .
5.07
8.80
7.05
5.03
Add 762.8 hr to all subsequent meter readings
A-9
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Mr. Morse summarized his testimony by stating that from the point of view
of public interest and feasibility, he felt that less stringent standards
should be adopted which roughly paralleled the California standards and
suggested a NOX standard of 1.0-1.5 gm/mi. This, in his view, would
result in both improved fuel economy and driveability.
Union Oil
The Union Oil Company testimony may be summarized as follows:
a. The automotive emission standards are too severe and should
be relaxed.
b. The 50,000-mile durability requirement for the catalyst
should be shortened.
c. Exhaust emission controls should be mandatory on all
cars on the road.
d. Annual inspection for all cars should be mandatory as a
condition of license renewal.
A-10
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
. REPORT NO.
PPA-460-3-74-027
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Status of Industry Progress Towards Achievement of
the 1975 Federal Emission Standards for Light Duty
Vehicle
5. REPORT DATE
Tilly 1Q77
6. PERFORMfNG ORGANIZATION CODE
7. AUTHOR(S)
W.V. Roessler, Toru lura, Joseph Meltzer
8. PERFORMING ORGANIZATION REPORT NO.
ATR-73(7322)-l
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
Aerospace Corp.
El Segundo, Calif.
11. CONTRACT/GRANT NO.
68-01-0417
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Protection Agency
Emission Control Technology Division
Ann Arbor, Michigan 48105
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
A compilation of the data available which showed the progress made as of mid 1972
by the Automobile Manufacturers toward meeting the 1975 model year emission
standards. Each approach to meeting the standards is discussed and referenced
to the manufacturers using that approach.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATI ricld/Group
Emissions
Automobile
Light-Duty Vehicle
Catalyst
Carburetion
Thermal reactor
Exhaust gas recirculation
8. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (This Report}
Unclassified
21. NO. OF PAGES
476
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
A-ll
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