United States
Environmental Protection
Agency
Air
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
2565 Plymouth Road
Ann Arbor, Michigan 48105
EPA 460/3-87-001
August 1987
vvEPA Vapor Generation of Fuels
-------
EPA 460/3-87-001
Vapor Generation of Fuels
by
Lawrence R. Smith
Southwest Research Institute
6220 Culebra Road
San Antonio, Texas 78284
Contract No. 68-03-3353
Work Assignment B-7
EPA Project Officer: Craig A. Harvey
Prepared for
ENVIRONMENTAL PROTECTION AGENCY
Office of Mobile Source Air Pollution Control
Emission Control Technology Division
2565 Plymouth Road
Ann Arbor, Michigan 48105
August 1987
-------
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
- in limited quantities - from the Library Services Office, Environmental Protection
Agency, 2565 Plymouth Road, Ann Arbor, Michigan 48105.
This report was furnished to the Environmental Protection Agency by Southwest
Research Institute, 6220 Culebra Road, San Antonio, Texas, in fulfillment of Work
Assignment No. B-7 of Contract 68-03-3353. The contents of this report are
reproduced herein as received from Southwest Research Institute. 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-460/3-87-001
11
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FOREWORD
This project was conducted for the U.S. Environmental Protection Agency by
the Department of Emissions Research, Southwest Research Institute. The program,
authorized by Work Assignment B-7 under Contract 68-03-3353, was initiated April
9, 1987 and completed in June 1987. It was identified within Southwest Research
Institute as Project 08-1193-007. The EPA Project Officer for the program was Mr.
Craig A. Harvey of the Emission Control Technology Division, Ann Arbor, Michigan.
The SwRI Project Leader and principal researcher for the project was Dr. Lawrence
R. Smith. Mr. Charles T. Hare was Project Manager and was involved in the initial
technical and fiscal planning.
in
-------
ABSTRACT
This report combines the data from two previous work assignments (V/ork
Assignments 12 and 18 of Contract 68-03-3192) conducted at Southwest Research
Institute for the Environmental Protection Agency, and analyzes the resulting data
set. When possible, the combined results have been generalized in order to draw
conclusions. In Work Assignment 12, vapors from twelve gasolines and
gasoline/alcohol blends were analyzed for butanes, total hydrocarbons, methanol,
and appropriate cosolvent alcohols. The analyses were conducted in duplicate for
each fuel at FTP diurnal SHED temperatures (60-84°F) and at typical hot soak
temperatures (160 ± 10°F). The fuels were prepared with different levels of
aromatic content and Reid Vapor Pressure. The Work Assignment 18 study involved
generating vapors from seven gasolines and gasoline/alcohol blends during simulated
diurnal test conditions (15-40°F, 35-60°F, and 60-84°F). These vapors were
analyzed for total hydrocarbons, alcohols, and individual hydrocarbons up to and
including C^,. The Reid Vapor Pressure of the seven fuels varied from 9.2 to 15.0
psi.
IV
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TABLE OF CONTENTS
Page
FOREWORD iii
ABSTRACT iv
LIST OF FIGURES vi
LIST OF TABLES vii
SUMMARY viii
I. INTRODUCTION 1
IL TEST FUELS, PROCEDURES, INSTRUMENTATION, AND
CALCULATIONS 2
A. Test Fuels 2
B. Diurnal Test Procedures 5
C. High-Temperature (160 ± 10°F) Test Procedure 9
D. Analytical Procedures and Calculations 10
IIL RESULTS 18
A. Diurnal Tests 18
B. High-Temperature Tests (160 ± 10°F) 27
IV. QUALITY ASSURANCE 29
APPENDICES
A. DIURNAL EVAPORATIVE EMISSIONS
B. HIGH TEMPERATURE EVAPORATIVE EMISSIONS
-------
LIST OF FIGURES
Figure Page
1 Fuel Tank as Used in the 60-84°F and
3 5-60° Tests 8
2 Fuel Tank as Used in the 15-40°F Tests 8
3 Flask and Water Bath for High-Temperature Tests 9
4 Individual Hydrocarbon Analysis System for Methane,
Ethane, Ethylene, Acetylene, Propane, Propylene,
Benzene, Toluene, Butane, and Isobutane 12
5 Standard Chromatogram for Cj - 3 Hydrocarbons,
Benzene, and Toluene 13
6 Sample Chromatogram (Test 2, Fuel EM-700-F) for
Cj - 03 Hydrocarbons, Benzene, and Toluene 14
7 Chromatogram of 995 ppmC Individual Hydrocarbon
Standard (C4 - Cfc) 16
8 Chromatogram of Sample for C4 - C^ Hydrocarbons
(Test 2, Fuel EM-700-F) 17
9 Plot of Total SHED Hydrocarbons Versus Fuel RVP
for the 60-80°F Diurnal Tests 21
10 Total SHED Hydrocarbon Results Grouped as to
Diurnal Temperature Range 23
11 Total SHED Hydrocarbon Results Grouped as io
RVP and Aromatic Content of the Test Fuel 24
VI
-------
LIST OF TABLES
Table Page
1 Low RVP - Low Aromatic Test Fuels
(Work Assignment 12) 3
2 High RVP - Low Aromatic Test Fuels
(Work Assignment 12) 4
3 Low RVP - High Aromatic Test Fuels
(Work Assignment 12) 6
4 Test Fuels (Work Assignment 18) 7
5 Average Diurnal Evaporative Emissions,
Work Assignment 12 Study 19
6 Average Diurnal Evaporative Emissions,
Work Assignment 18 Study 20
7 Individual Hydrocarbons as Percentage of Total
Non-Oxygenated Hydrocarbons, Work Assignment
18 Study 25
8 Average High Temperature Evaporative Emissions 28
9 SHED Validation Experiments 29
10 Validation Results for Alcohol Bag Sampling
Technique at Varying Relative Humidity Levels 31
Vll
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SUMMARY
Fuel vapors generated from the SHED testing of a variety of gasolines and
gasoline/alcohol blends, utilizing three diurnal temperature rise situations (15-40°,
35-60°, 60-84°F) as well as a high temperature (160° ± 10°F) situation, were
characterized as to total SHED hydrocarbons, individual hydrocarbons (up to and
including C&), and alcohols. Twelve gasolines and gasoline/alcohol blends (Work
Assignment 1Z) were evaluated as to alcohol content, Reid Vapor Pressure, and
aromatic content using the 60-84°F diurnal temperature rise and the high
temperature test, while seven other gasolines and gasoline/alcohol blends (Work
Assignment 18) were evaluated as to fuel volatility using all three of the diurnal
temperature rise situations. In the twelve-fuel study, gasoline and
gasoline/methanol, gasoline/methanol-TBA, and gasoline/methanol-ethanol blends
were evaluated in the following combinations of fuel properties: low RVP-low
aromatic content, high RVP-low aromatic content, and low RVP-high aromatic
content. In the seven-fuel study, three of the gasoline fuels were representative of
ASTM (D-439) Class C, D, and E fuels, while a fourth gasoline was Indolene. Three
gasoline/alcohol blends were also high-volatility Class C, D, and E fuels and
contained 5.0% methanol and 2.5% ethanol as a cosolvent. The three diurnal
temperature rise situations included: the standard summer diurnal temperature rise,
60-84°F, for the Class C gasoline and gasoline/alcohol blend and Indolene testing; a
winter diurnal temperature rise, 15-40°F, for the Class E gasoline and
gasoline/alcohol blend testing; and a spring diurnal temperature rise, 35-60°F, for
the Class D gasoline and gasoline/alcohol blend testing.
A 10-gallon fuel tank filled to 40 percent capacity was used to generate the
vapors in the diurnal SHED tests (no test vehicle was used), and a 250 ml flask filled
with 125 ml of fuel and heated with a water bath to 160°F was used to generate
vapors in the high-temperature tests. Duplicate tests were conducted at each test
condition.
The most significant observations made from the data (not necessarily in
order) are as follows:
In the diurnal test, total SHED hydrocarbons appear to follow fuel RVP
trends, with the higher RVP fuels giving higher total hydrocarbons. In the
higher temperature tests this trend was also noted, but a closer
relationship of the fuel distillation curve with the SHED total hydrocarbons
was observed. Fuels with a larger fraction of the fuel boiling at
temperatures lower than the 160°F test temperature gave correspondingly
higher SHED hydrocarbon emissions.
Variations in fuel aromatic content did not appear to alter total
hydrocarbon emissions in the diurnal and high-temperature SHED tests as
significantly as the RVP and distillation temperature variations. The
aromatic content of the fuel, however, did influence the fuel RVP and
distillation curve.
In general, SHED total hydrocarbons were found to increase with increasing
diurnal temperature rise (15-40°F < 35-60°F < 60-84°F) despite a
corresponding decrease in test fuel volatility.
viii
-------
Individual hydrocarbons in the diurnal SHED tests followed the same trends
as the total hydrocarbons.
Propylene, ethylene, ethane, and methane were found in fuel vapors in
small but measurable quantities and were apparently present in the fuel
itself at trace levels.
Propane was detected in the fuel vapors for all the fuels tested, with
average levels ranging from 0.13 to 0.33 g/test.
Benzene was found to constitute one percent or less of the total vapor
hydrocarbons for the seven fuels. Test fuels prepared from similar base
stock fuels gave similar benzene levels in the hydrocarbon vapors.
Isobutane, n-butane, isopentane, and pent an e made up the majority of the
total diurnal SHED hydrocarbons in the Work Assignment 18 study, with
combined percentages ranging from 71.2% to 81.6%.
Butane and isobutane SHED levels in the Work Assignment 12 study were
found to be directly related to the butane and isobutane levels in the fuels.
Generally, the alcohol blends had lower levels of isobutane and n-butane in
the total SHED hydrocarbons than their corresponding base gasolines. This
was likely due to both the removal of some of the light ends during the
preparation of the blends and to the dilution of these compounds by the
addition of the alcohols. Many of the higher boiling GS and C£ compounds,
however, were generally present in higher percentages in the alcohol blend
vapors than in the base gasoline vapors. The formation of
methanol/hydrocarbon azeotropes in the alcohol blends may have
contributed to these higher percentages.
Percentages of olefins in the SHED hydrocarbons (7-14%) were high in
relation to levels typically found in gasoline (<10%). This higher
percentage may be a result of higher concentrations of fuel olefins in the
64 to C(y fuel fraction as opposed to the whole fuel.
As was the case for total hydrocarbons, SHED methanol levels increased
with increasing diurnal test temperatures despite a decrease in fuel
volatility.
In general, higher-RVP fuels gave higher levels of alcohols in both the Work
Assignment 12 diurnal and the high-temperature SHED tests. SHED
methanol levels were 1.5 to 7 fold higher in diurnal SHED tests and 1.2 to 2
fold higher in the high-temperature tests for the higher-RVP fuels when
compared to the lower-RVP fuels of equal alcohol content. Levels of
methanol in the high-temperature SHED tests appeared to be roughly
proportional to the levels of methanol in the fuel. Levels of ethanol and
TEA found in the diurnal and in the high-temperature SHED tests were
much lower than the corresponding levels of methanol. In the Work
Assignment 18 study, ethanol was detected during the 60-84°F testing of
the Class C gasoline/alcohol blends, but not in any of the lower
temperature tests.
IX
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Methanol content of the total diurnal hydrocarbons, with
methanol/cosolvent blends, ranged from 4.3-9.3% in the Work Assignment
18 study and 5.4-15.6% in the Work Assignment 12 study. In the high
temperature part of Work Assignment 1Z, the corresponding range was
13.7-18.3%.
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L INTRODUCTION
The objectives of this work assignment were to combine the data generated in
two previous work assignments (Work Assignments 12 and 18 of Contract 68-03-
3192) and to reanalyze the resulting data set to give a single final report. In the
Work Assignment 12 evaluations, vapors from twelve gasolines and gasoline/alcohol
blends were analyzed for butanes, total hydrocarbons, methanol, and appropriate
cosolvent alcohols. The analyses were conducted in duplicate for each fuel at FTP
diurnal SHED temperatures (60-84°F) and at typical hot-soak temperatures (160
10°F). The fuels were prepared with different levels of aromatic content and Reid
Vapor Pressure. The Work Assignment 18 study involved generating vapors from
seven gasolines and gasoline/alcohol blends (representing fuel volatility Classes C,
D, and E) during simulated diurnal test conditions (15-40°F, 35-60°F, and 60-84°F).
These vapors were analyzed for total hydrocarbons, alcohols, and individual
hydrocarbons up to and including C(,. In the two previous work assignments, total
hydrocarbons were calculated for gasoline/alcohol blends from uncorrected FID
total hydrocarbon levels. In this study, the FID response for the alcohols has been
subtracted from the FID total hydrocarbon levels to give a total non-oxygenated
hydrocarbon level. This non-oxygenated hydrocarbon SHED value is then combined
with the alcohol SHED values to give a corrected total SHED hydrocarbon value.
A ten-gallon fuel tank (no test vehicle) filled to 40 percent capacity was used
to generate the vapors for the diurnal tests in both work assignments, and a 250 ml
vacuum flask filled with 125 ml of fuel and heated with a water bath to 160°F was
used to generate vapors in the simulated hot soak tests in Work Assignment 12.
SHED vapors were collected in Tedlar bags and analyzed for total uncorrected FID
hydrocarbons, individual hydrocarbons, and the alcohols methanol, ethanol, and
tertiary butyl alcohol (TEA).
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IL TEST FUELS, PROCEDURES, INSTRUMENTATION, AND CALCULATIONS
This section describes the fuels, procedures, instrumentation, and calculations
used in the two Work Assignments. A total of nineteen fuels, three simulated
diurnal temperature rise scenarios, and a simulated hot-soak scenario were utilized
in these programs. Evaporative emissions were collected in Tedlar bags from a
sealed housing for evaporative determinations (SHED) and analyzed for total
hydrocarbons, various individual hydrocarbons up to and including C^ hydrocarbons,
and the alcohols methanol, ethanol, and tertiary butyl alcohol.
A. Test Fuels
Nineteen fuels were used in this study, twelve in the Work Assignment 1Z
investigations and seven in the Work Assignment 18 investigations. The twelve fuels
evaluated in Work Assignment 12 were tested in duplicate at diurnal SHED
temperatures (60-84°F) and at high temperatures (160 ± 10°F). The seven fuels
evaluated in Work Assignment 18 were tested in duplicate over three diurnal SHED
temperature ranges (15-40°F, 35-60°F, and 60-84°F).
1. Work Assignment 1Z Fuels
The twelve fuels tested in Work Assignment 1Z were all prepared from a
single batch of fuel having the SwRI Code EM-616-F (regular unleaded Gulf Crest).
This fuel had a Reid Vapor Pressure (RVP) of 9.Z psi and aromatic content of Z6.8
percent. Three groups of fuels were prepared from the base fuel: a low RVP (8.4 to
9.Z psi), low aromatic (~Z5 percent) group; a high RVP (11.5 to 1Z.O psi), low
aromatic (~Z5 percent group); and a low RVP (8.8 to 9.5 psi), high aromatic (~45
percent) group.
The low RVP - low aromatic fuels consisted of the starting base fuel,
EM-616-F, and. three alcohol blends. These blends were prepared by bubbling
nitrogen through the base fuel until the RVP was reduced to 6.9 psi, followed by the
addition of alcohols. Blend EM-64Z-F was prepared by adding 4.75 volume percent
methanol and 4.75 volume percent TEA to the reduced-RVP fuel. Blend EM-643-F
was prepared from the reduced-RVP base fuel by the addition of 5.0 volume percent
methanol and Z.5 volume percent ethanol; and blend EM-644-F was prepared by the
addition of 5 volume percent methanol. Selected fuel properties for these four test
fuels are presented in Table 1. The RVP values for the alcohol blends, EM-64Z-F
(8.45) and EM-643-F (8.40), were lower than anticipated (expected RVP of 9.0),
because the addition of the alcohols produced only a 1.5 psi increase in RVP.
Addition of the alcohols to the unaltered base fuel (RVP of 9.Z) gave increases of Z.4
to Z.8 psi in RVP. These observations illustrate the complexity of preparing alcohol
blends.
The second group of fuels, high RVP with low aromatics, consisted of
three alcohol blends prepared by the direct addition of alcohols to the base fuel,
EM-616-F (blend EM-638-F, 4.75 volume percent methanol, 4.75 volume percent
TBA; blend EM-639-F, 5.0 volume percent methanol, Z.5 volume percent ethanol;
and blend EM-640-F, 5.0 volume percent methanol); and a fourth fuel (EM-641-F)
prepared by the addition of n-butane to fuel EM-616-F to give an RVP in the range
of the three alcohol blends. These four fuels are described in Table Z.
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TABLE 1. LOW RVP - LOW AROMATIC TEST FUELS
(WORK ASSIGNMENT 12)
Fuel Code
Methanol, Vol. %
Cosolvent, Vol. %
RVP, psi
Aromatics, %
Butane, g/gal
Isobutane, g/gal
Distillation-D86
°C (°F)
IBP
5%
10%
15%
20%
30%
40%
50%
60%
70%
80%
90%
95%
EP
Recovery, %
Residue, %
EM-616-F EM-642-F
4.75
4.7 5 (TEA)
9.20
26.8
94
32
31(88)
44(112)
51(124)
58(136)
64(148)
77(170)
90(194)
104(219)
118(245)
133(272)
151(303)
174(345)
195(383)
208(406)
97.5
1.5
8.45
26.8a
14
2.1
36(97)
47(117)
51(123)
55(131)
58(137)
69(157)
85(185)
101(214)
118(244)
133(272)
149(300)
171(340)
192(378)
208(407)
98.0
1.0
EM-643-F
5.00
2.50(EtOH)
8.40
NRb
NR
NR
36(97)
47(116)
51(123)
54(129)
57(134)
68(154)
89(193)
104(220)
118(244)
134(273)
151(303)
171(340)
187(368)
208(406)
98.0
1.0
EM-644-F
5.00
9.15
NR
NR
NR
32(89)
47(116)
48(119)
51(123)
53(128)
80(176)
96(204)
107(225)
121(250)
134(274)
149(300)
170(338)
187(368)
208(407)
99.0
1.0
aCalculated value based on 9.5% loss of light-end saturates and the addition
of 9.5 volume percent alcohols. The ASTM FIA method gave an aromatic
concentration of 33.3 percent, however this method was designed for
gasoline fuels and its reliability for alcohol blends is unknown
- not required
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TABLE 2. HIGH RVP - LOW AROMATIC TEST FUELS
(WORK ASSIGNMENT 12)
Fuel Code
Methanol, Vol. %
Cosolvent, Vol. %
RVP, psi
Aromatics, %
Butane, g/gal
Isobutane, g/gal
Distillation-D86
EM-641-F EM-638-F
4.75
4.75(TBA)
IBP
5%
10%
15%
20%
30%
40%
50%
60%
70%
80%
90%
95%
EP
Recovery, %
Residue, %
11.55
21.5
139
23
26(79)
37(99)
44(111)
50(122)
57(135)
71(160)
86(187)
101(214)
116(240)
131(267)
149(300)
172(342)
197(386)
208(406)
98.0
1.0
11.60
24.3 a
85C
29 c
30(86)
39(103)
44(111)
48(119)
53(127)
61(141)
77(170)
92(198)
109(228)
128(262)
145(293)
168(334)
185(365)
206(402)
98.0
1.0
EM-639-F
5.00
2.50(EtOH)
11.85
NRb
NR
NR
31(87)
39(103)
44(111)
48(118)
52(125)
57(135)
73(163)
97(206)
112(234)
128(262)
145(293)
168(334)
186(366)
207(405)
98.0
1.0
EM-640-F
5.00
12.00
NR
NR
NR
29(85)
38(101)
41(106)
45(113)
48(118)
60(140)
82(180)
98(208)
113(236)
128(263)
146(294)
167(332)
186(366)
208(406)
98.0
1.0
aCalculated value based on the addition of 9.5% alcohols to the base fuel
EM-616-F, which had an aromatic content of 26.8. The ASTM FIA method
gave an aromatic concentration of 26.8 percent, however this method was
designed for gasoline fuels and its reliability for alcohol blends is
unknown
^NR - not required
cCalculated value, EM-638-F prepared by blending EM-616-F (90.5%) with methanol
(4.75%) and TEA (4.75%). EM-638-F Butane and Isobutane values calculated by
multiplying EM-616-F concentrations by a 0.905 factor.
-------
The third group of fuels was prepared by initially adding mixed xylenes
to base fuel EM-616-F to give a high aromatic fuel (~45 percent aromatics),
followed by subsequent mixing with alcohols to give blends EM-646-F, EM-647-F,
and EM-648-F, or with n-butane to give base fuel EM-645-F. Table 3 gives selected
properties for these fuels.
2. Work Assignment 18 Fuels
The seven test fuels that were evaluated in the Work Assignment 18
segment of the study, along with their corresponding RVP and distillation data, are
listed in Table 4. Fuel EM-697-F (Gasoline, Class E) is a commercial grade unleaded
gasoline and was obtained in two 55-gallon drums from Mr. Pete Gabele of RTP-
EPA. Fuel EM-690-F (Gasoline, Class D) is winter grade regular unleaded Gulf
Crest and was obtained locally. Fuel EM-70Z-F (Gasoline, Class C) was prepared by
blending EM-690-F and EM-616-F in a 3:2 ratio. EM-616-F was also used as the base
fuel in the Work Assignment 12 investigations. EM-700-F was unleaded Amoco
Indolene and was obtained in 55-gallon drum quantities. Alcohol blends EM-703-F,
EM-701-F and EM-698-F were prepared from the corresponding volatility class base
fuels, EM-702-F, EM-690-F, and EM-697-F, respectively. To prepare the blends, the
base fuels were first bubbled with nitrogen to lower the RVP, followed by the
addition of appropriate quantities of methanol and ethanol.
8. Diurnal Test Procedures
Three different diurnal temperature rise scenarios were used in the combined
study: 60-84°F, 35-60°F, and 15-40°F. The 60-84°F scenario was used for all fuels
in Work Assignment 12, for the Class C gasoline and gasoline/alcohol blend in Work
Assignment 18, and for Indolene in Work Assignment 18. The 35-60°F scenario was
used for the Class D gasoline and gasoline/alcohol blend in Work Assignment 18, and
the 15-40°F scenario was used for the Class E gasoline and gasoline/alcohol blend in
Work Assignment 18. The three scenarios were conducted in a manner similar to the
diurnal test as specified in the Federal Test Procedure (FTP) for light-duty gasoline-
fueled vehicles; with the exceptions that only a vehicle fuel tank (no test vehicle)
was used in the tests, and evaporative vapors were collected from the SHED in
Tedlar bags for subsequent analysis as opposed to vapor analysis with a continuous
hydrocarbon analyzer.
For each test, a 10-gallon capacity fuel tank was filled with 4 gallons of
precooled test fuel. With the exceptions of the tubing that had been previously
connected to the evaporative charcoal canister, all openings to the fuel tank were
then plugged. For the 60-84°F and the 35-60°F tests, heating blankets were
attached to the bottom of the tank; the tank was placed in the SHED, and
appropriate electrical and thermocouple connections were made (Figure 1). No
external heating was required for the fuel tank in the 15-40°F tests, so the heating
blankets were not attached to the bottom of the tank before placing it in the SHED.
In fact, some additional tank insulation was required to keep the tank from warming
up too rapidly in the SHED. This additional insulation was accomplished by placing
the tank on sealed Tedlar bags containing polystyrene foam peanuts (Figure 2).
When the fuel temperature was within 4 to 5 minutes of reaching the initial
temperature point, the SHED purge system was closed and the SHED sealed. At this
point a background Tedlar bag sample (~5 cubic feet of sample) was collected from
-------
TABLE 3. LOW RVP - HIGH AROMATIC TEST FUELS
(WORK ASSIGNMENT 1Z)
Fuel Code
Methanol, Vol. %
Cosolvent, Vol. %
RVP, psi
Aromatics, %
Butane, g/gal
Isobutane, g/gal
Distillation-D86
EM-645-F EM-646-F
4.75
4.7 5 (TEA)
IBP
5%
10%
15%
Z0%
30%
40%
50%
60%
70%
80%
90%
95%
EP
Recovery, %
Residue, %
9.36
49.1
157
20
28(85)
41(105)
50(122)
61(141)
72(161)
94(201)
113(235)
125(257)
133(272)
139(282)
144(292)
156(312)
177(350)
204(400)
98.0
1.0
8.80
44.3 a
57
17
24(75)
49(121)
54(129)
58(137)
63(145)
82(179)
104(219)
123(253)
133(271)
138(281)
144(291)
154(309)
171(340)
203(398)
98.0
1.0
EM-647-F
5.00
2.50(EtOH)
9.10
NRb
NR
NR
36(97)
48(119)
53(128)
57(135)
59(139)
77(171)
109(229)
125(257)
134(274)
141(286)
146(295)
157(315)
176(348)
203(397)
98.0
1.0
EM-648-F
5.00
9.55
NR
NR
NR
32(89)
47(117)
51(123)
53(127)
57(135)
94(201)
113(236)
127(260)
134(274)
139(282)
146(294)
157(314)
186(366)
204(400)
98.0
1.0
Calculated value based on the addition of mixed xylenes to raise the aromatics
to 48.9% followed by the addition of 9.5% volume percent alcohols. The ASTM FIA
method gave an aromatic concentration of 48.6 percent, however this method
was designed for gasoline fuels and its reliability for alcohol blends
is unknown
- not required
-------
TABLE 4. TEST FUELS (WORK ASSIGNMENT 18)
Fuel
Volatility Class
Fuel Code
Methanol, Vol%
Ethanol, Vol %
RVP, psi
Distillation - D86
IBP
5%
10%
15%
20%
30%
40%
50%
60%
70%
80%
90%
95%
EP
Recovery, %
Residue, %
Gasoline
E
EM-697-F
14
23
33
39
46
53
69
88
103
113
123
139
167
185
202
98
1.
.0
(74)
(92)
(103)
(114)
(127)
(157)
(190)
(217)
(236)
(254)
(283)
(332)
(365)
(395)
.0
0
Gasoline
D
EM-690-F
12
24
38
44
50
56
67
78
89
104
118
134
156
173
197
98
1.
.0
(76)
(101)
(112)
(122)
(132)
(152)
(172)
(193)
(220)
(245)
(274)
(312)
(344)
(386)
.0
0
Gasoline
C
EM-702-F
10
26
40
46
52
58
70
82
95
109
124
141
164
184
206
98
1.
.9
(79)
(104)
(114)
(126)
(137)
(158)
(180)
(203)
(229)
(256)
(286)
(328)
(363)
(402)
.0
0
Indolene
EM-700-F
9.
26
43
54
64
74
91
102
109
115
123
138
170
194
218
98
1.
2
(79)
(110)
(130)
(148)
(165)
(195)
(215)
(228)
(239)
(253)
(280)
(338)
(382)
(424)
.0
0
Blend
C
EM-703-F
5.0
2.5
11.5
33 (91)
43(109)
46(115)
49(120)
52(125)
57(135)
73(163)
93(200)
109(228)
123(254)
140(284)
162(323)
178(352)
199(391)
98.0
1.0
Blend
D
EM-701-F
5.0
2.5
13
31
40
44
47
50
55
65
76
102
117
134
157
178
190
98
1.
.2
(87)
(104)
(111)
(116)
(122)
(131)
(149)
(168)
(215)
(242)
(274)
(314)
(352)
(374)
.0
0
Blend
E
EM-698-F
5.0
2.5
15.0
24 (75)
36 (96)
40 (104)
44 (111)
48 (119)
56 (133)
69 (157)
99 (211)
112 (233)
122 (252)
136 (276)
164 (327)
181 (358)
192 (377)
98.0
1.0
-------
FIGURE 1. FUEL TANK AS USED IN THE 60-84°F AND 35-60°F TESTS
FIGURE 2. FUEL TANK AS USED IN THE 15-40op TESTS
-------
the SHED over a six- to eight-minute time period. This collection period is
necessary in order to obtain a sufficient volume of sample for the alcohol analysis,
as well as sample for the total and individual hydrocarbon analyses. The midpoint of
this background sample period was targeted for the initial test temperature (15, 35,
or 60°F). For the 60-84°F test, the fuel tank was then heated, over a 60 minute
period, from 60 to 84°F. For the 35-60°F test, intermittent heating was used to
raise the temperature from 35 to 60°F over a 60 ± 6 minute time period. Because of
the lack of external heating control, the temperature rise for the 15-40°F was not
as linear as for the 60-84°F and the 35-60°F tests. A Tedlar bag sample was
collected for each test starting at 3 to 4 minutes before the fuel reached the final
test temperature (40, 60, or 84°F), and for an equal time period after the fuel
reached the final temperature. Once again, the midpoint of the sample collection
period was targeted for the appropriate final test fuel temperature. After sample
collection, the SHED was opened, the fuel tank removed, and the SHED purged for
the next test. The fuel was drained from the fuel tank, and the fuel tank rinsed with
the next test fuel before the test sequence was repeated.
C. High-Temperature (160 ± 10°F) Test Procedure
For the twelve Work Assignment 1Z fuels, high-temperature tests were
performed to simulate vapor generated from a carbureted vehicle under hot soak
conditions. In these tests, a 1Z5 ml volume of test fuel was placed in a 250 ml flask
with a side arm opening. The top of the flask was sealed, and a vent tube of
approximately two feet in length (tubing obtained from an actual evaporative
control system) was attached to the side arm and closed with a pinch clamp. The
flask of fuel, containing a thermocouple to monitor fuel temperature, was then
placed in the SHED along with a preheated water bath (Figure 3). For a background
FIGURE 3. FLASK AND WATER BATH FOR HIGH TEMPERATURE TESTS
-------
sample, the SHED purge system was closed, the SHED sealed, and a six-to-eight-
minute bag sample was collected in a Tedlar bag. The SHED was then briefly
opened to allow someone to enter the SHED, open the pinch clamp on the tubing and
lower the flask of fuel into the water bath. The SHED was then quickly sealed and
the test initiated. Within approximately 10 minutes the fuel temperature reached
the 150 to 160°F temperature range. For an additional 50 minutes the fuel
temperature in the flask was maintained at 160 ± 10°F. At 56 to 57 minutes into
the test, the collection of a Tedlar bag sample was initiated and continued for 6 to 8
minutes, with the midpoint of the sampling time at 60 minutes into the test. After
sample collection the SHED was opened, the flask of fuel removed, and the SHED
purged for the next test. During the initial part of the test (0-10 minutes) the fuel
simply distilled from the flask until the lower-boiling materials were removed by
distillation. This distillation period accounts for the fuel temperature remaining
below 160 ± 10°F during the first 10 minutes of the test. In some cases, the fuel
condensed in the two feet of vent tubing, and as a result, liquid dripped from the
tubing to the SHED floor. While this volume of liquid was small, at the conclusion
of each test it was necessary to wipe this fuel from the SHED floor before
proceeding to the next test.
D. Analytical Procedures and Calculations
Evaporative emissions were collected in Tedlar bags from the SHED at the
beginning (background) and end (sample) of each diurnal and high-temperature test.
Analyses for total hydrocarbons, various individual hydrocarbons, and alcohols
(methanol, ethanol, or tertiary butyl alcohol) were conducted on each background
and sample bag. Total hydrocarbon and individual hydrocarbon analyses were
conducted directly on the vapors in the bags; however, for the alcohol analyses, 4 to
5 cubic feet of vapor from each background or sample bag were concentrated in
water by pulling the bagged vapors through two impingers, each containing 25 ml of
water. The water samples from these impingers were then analyzed for the alcohols
with the aid of a gas chromatograph. The instrumentation, procedures, and
calculations used to quantify the total hydrocarbons, individual hydrocarbons, and
alcohols are discussed briefly in the following sections.
1. Alcohols (methanol, ethanol, and tertiary butyl alcohol)
The analyses for the alcohols methanol, ethanol, and tertiary butyl alcohol
were conducted using the GC-FID procedure described in the report "In-Use
Evaporative Canister Evaluation," EPA Report No. 460/3-85-003, Work Assignment
27 of EPA Contract 68-03-3162. In this study, the evaporative vapors were first
collected from the SHED in Tedlar bags (4 to 5 ft3 of vapors) and then bubbled
through two glass impingers each containing 25 ml of deionized water maintained at
ice bath temperatures. This two-step process allowed the evaporative vapors to be
pulled through the impingers at a more optimum flow rate than would be practical
for direct SHED sampling. For analysis, a portion of the aqueous solution was
injected into a gas chromatograph equipped with a flame ionization detector.
Appropriate external alcohol standards were used to quantify the results.
Calculations for the mass of alcohols in the SHED were performed using the
results from the analytical procedure in /ig/m3 (dry volume) and the net dry SHED
volume in cubic meters. Relative humidity measurements were taken in the SHED
during each test to permit the dry SHED volume calculations to be made.
10
-------
2. Total Hydrocarbons (THC)
The bagged evaporative emission samples were analyzed for total
hydrocarbons using the FID analyzer in SwRI Bag Cart Number 1. This bag cart was
designed, calibrated, and operated in accordance with the appropriate sections of
the Code of Federal Regulations for light-duty vehicle emissions certification. To
calculate the amount of total hydrocarbons (grams) in the SHED for each test with a
non-alcohol-containing fuel, the following equation from the Code of Federal
Regulations (Title 40, Part 86, Section 143-78} for calculating evaporative emissions
was used:
10-4 cHCfPBf _
Tf
where:
PBjl
i J
= hydrocarbon mass, grams
= hydrocarbon concentration as ppm carbon
Vn = net enclosure volume, ft^. Determined for this study by
subtracting 2 ft-* for the fuel tank volume (diurnal test) or 1 ft-*
for flask and water bath (hot soak tests) from the enclosure
volume
Pg = barometric pressure, in. Hg
T = enclosure ambient temperature, R
k = 0.208 (12 + H/C)
H/C = 2.33 for the diurnal test
H/C = 2.20 for the hot-soak test (and used in this study for the
high temperature tests)
i = indicates background bag for this study
f = indicates sample bag for this study
Because alcohols have a FID hydrocarbon response that differs
significantly from the non-oxygenated gasoline-derived hydrocarbons, and the
equation in the Code of Federal Regulations for calculating evaporative emissions
does not include a term for oxygen mass in the calculations, an alternate method
must be used to determine the total hydrocarbons in the tests with alcohol-
containing fuels. The method used in this study consists of first subtracting
appropriate ppmC values for the alcohols from the bag cart FID total ppmC values.
The ppmC for the remaining non-oxygenated hydrocarbons is then used in the Code
of Federal Regulation equation to determine a mass value. This non-oxygenated
hydrocarbon mass can then be added to the mass of each of the individual alcohols
to give a total hydrocarbon value.
The pprnC subtracted for each of the alcohols is determined by first
converting the alcohol mass in jig/m^ to ppm alcohol. This can be accomplished by
dividing the ^g/m-* alcohol value by 1333 ^g/ppra for methanol, 1916 /^g/ppm for
ethanol, and 3083 jig/ppm for TEA. For ethanol and TEA, the ppm alcohol values
must be multiplied by the number of carbons in each alcohol, 2 and 4, respectively,
to give the ppmC values. Before the ppmC alcohol values can be subtracted from
the bag cart FID ppmC values, they must be corrected for humidity removal and for
their non-unity response in the FID. Methanol and ethanol were found to have 0.79
11
-------
FID response factors, while TEA was found to have an FID response factor of 0.94
(i.e., an FID "sees" 10 ppmC methanol as 7.9 ppmC, therefore 10 ppmC methanol
must be multiplied by 0.79 before the methanol value can be subtracted from the
bag cart FID value).
2. Individual Hydrocarbons
The individual hydrocarbon analyses (Cj to C(, plus toluene and 2,4-
dimethylpentane) were conducted using two separate gas chromatograph systems.
The first system provides concentrations for selected individual hydrocarbons
including methane, ethane, ethylene, acetylene, propane, propylene, benzene, and
toluene. This system is described in detail in EPA Report 600/2-79-017, "Analytical
Procedures for Characterizing Unregulated Pollutant Emissions from Motor
Vehicles," and is illustrated in Figure 4. It utilizes a gas chromatograph system
containing four separate columns and a flame ionization detector. Sample peak
areas are compared to an external calibration blend containing each of the eight
hydrocarbons analyzed. Reported hydrocarbon concentrations include FID response
corrections for each of these eight hydrocarbons. A standard and sample
chromatogram are illustrated in Figures 5 and 6. This system was modified in the
Work Assignment 12 investigations to provide concentrations for n-butane and
isobutane.
FIGURE 4. INDIVIDUAL HYDROCARBON ANALYSIS SYSTEM FOR
METHANE, ETHANE, ETHYLENE, ACETYLENE, PROPANE,
PROPYLENE, BENZENE, TOLUENE, BUTANE,
AND ISOBUTANE
12
-------
Methane
-__i_ ... :..' _t -- . r^r^
. III Propylene
0
Retention Time, Minutes
FIGURE 5. STANDARD CHROMATOGRAM FOR Cj - C3 HYDROCARBONS, BENZENE, AND TOLUENE
-------
20
Retention Time, Minutes
FIGURE 6. SAMPLE CHROMATOGRAM fTEST Z, FUEL EM-700-F) FOR Cj - C3 HYDROCARBONS,
BENZENE, AND TOLUENE
-------
In the Work Assignment 12 investigations, the analysis time for the
procedure was extended to permit 04 peak elution and quantification. Butane
standards (n-butane) were prepared by adding n-butane gas to zero air in Tedlar
bags. The butane standard bags were named with a FID hydrocarbon analyzer
against propane standards traceable to NBS standards. Relative response factors for
propane and n-butane from "Basic Gas Chromatography11 by H. M. McNair and E. J.
Bonelli, Varian Aerograph, 1968, were used to give actual n-butane concentrations in
ppmC (n-butane has a relative response factor of 1.11 per carbon in relation to 1.00
for propane). For this study, the FID response factor for isobutane was assumed to
be equivalent to that for n-butane.
In the Assignment 18 investigations, butane, isobutane and the remainder
of the hydrocarbons, 64 - C& plus 2,4-dimethylpentane, were analyzed using a
second gas chromatograph system. It was equipped with subambient capabilities, a
capillary column and a FID detector; and the individual hydrocarbons were
quantified using a standard containing n-butane, isobutane, isopentane, pentane, 2,2-
dimethylbutane, cyclopentane, 2,3-dimethylbutane, 2-methylpentane, 3-
methylpentane, hexane, methylcyclopentane, 2,4-dimethylpentane, and benzene.
Because individual FID response factors were not available for all of the compounds,
the standard was named using propane as a reference gas. As a result, the values
for these compounds do not include the individual FID response factor corrections
(all assumed to be 1.00). The capillary column used in the system is a Perkin-Elmer
F-50 Versilube, 150 ft x 0.020 inch WCOT stainless steel column. The column is
initially cooled to -139°F (-95°C) for sample injection. Upon injection, the
temperature is programmed at a 7°F (4°C) increase per minute for approximately 31
minutes (until benzene elutes). A chromatogram of a 995 ppmC individual
hydrocarbon standard is illustrated in Figure 7, and a chromatogram of a sample
(Test 2, Fuel EM-700-F) is illustrated in Figure 8.
Calculations for determining the mass of each individual hydrocarbon in
the SHED were performed using the equation for the total hydrocarbons. The ppmC
value of the individual hydrocarbon concentrations was used in place of the total
hydrocarbon ppmC concentrations, and an actual H/C ratio for each individual
hydrocarbon was used in both the diurnal and high temperature calculations in place
of the 2.33 diurnal THC value and the 2.20 high temperature THC value.
15
-------
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Retention Time, Minutes
FIGURE 7. CHROMATOGRAM OF 995 PPMC INDIVIDUAL HYDROCARBON STANDARD (C4
-------
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Retention Time, Minutes
10
FIGURE 8. CHROMATOGRAM OF SAMPLE FOR C4 - Cfc HYDROCARBONS (TEST 2, FUEL EM-700-F)
-------
RESULTS
SHED tests were conducted in duplicate utilizing three diurnal temperature
rise scenarios (15-40°, 35-60°, and 60-84°F) and nineteen gasolines and
gasoline/alcohol blends. The 60-84°F diurnal test was used to evaluate twelve of
the test fuels, while all three of the diurnal rise scenarios were used in evaluating
the remaining seven fuels. The 60-84°F diurnal test was used for a Class C
volatility gasoline and gasoline/alcohol blend and Indolene; the 35-60°F diurnal test
was used for a Class D volatility gasoline and gasoline/alcohol blend; and the 15-
40°F diurnal test was used for a Class E volatility gasoline and gasoline/alcohol
blend. Twelve of the test fuels were also evaluated at high temperatures (160 ± 10°)
to simulate vehicle hot soak losses.
A ten-gallon fuel tank (no test vehicle) filled to 40 percent capacity was used
to generate the vapors for the diurnal tests, and a 250 ml vacuum flask filled with
125 ml of fuel and heated with a water bath to 160°F was used to generate vapors in
the simulated hot soak tests. SHED vapors were collected in Tedlar bags and
analyzed for total uncorrected FID hydrocarbons, individual hydrocarbons, and the
alcohols methanol, ethanol, and tertiary butyl alcohol. The following sections
discuss the results for the simulated diurnal and high-temperature tests.
A. Diurnal Tests
Two sets of experiments were conducted utilizing simulated diurnal tests. One
set, conducted in Work Assignment 12, utilized the 60-84°F temperature rise with
twelve test fuels, while the second, a Work Assignment 18 study, involved the use of
three diurnal rise scenarios and seven test fuels. The average SHED results for
these two sets of experiments are presented in Tables 5 and 6, and the individual
SHED test results are presented as Appendix Tables A-l through A-19. The
following sections discuss diurnal SHED test results for total hydrocarbons,
individual hydrocarbons, and alcohols.
1. Total Hydrocarbons
The total hydrocarbons, as reported in this study, include both the non-
oxygenated hydrocarbon emissions (equivalent to the total hydrocarbons for the
gasoline fuels) and the alcohol emissions. With the exception of Fuel EM-690-F, the
repeatability of the total hydrocarbon test results for each fuel tested was good;
individual test results were within 10% of the reported averages in Tables 5 and 6.
The repeatability of the two tests on Fuel EM-690-F was not as good; the individual
tests were 23% higher and lower than the average value in Table 5.
For the diurnal tests conducted at 60-84°F (in both Work Assignment 12
and 18 investigations), the total SHED hydrocarbons appear to follow fuel RVP
trends, with the higher RVP fuels giving higher total hydrocarbons. A linear
regression plot of the total SHED hydrocarbons versus the fuel RVP for all 15 fuels
tested at 60-84°F gave an r2 of 0.88. A plot of the total SHED hydrocarbons versus
fuel RVP is displayed in Figure 9. Linear regression plots of total SHED
hydrocarbons versus the fuel RVP for the gasoline fuels only and the
gasoline/alcohol blends only were slightly better, with r2 = 0.90 in both cases.
18
-------
TABLE 5. AVERAGE DIURNAL EVAPORATIVE EMISSIONS,
WORK ASSIGNMENT 1Z STUDY
Fuel
Fuel Code
Methanol, vol. %
Ethanol, vol. %
TBA, vol. %
RVP, psi
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCC
Total Hydrocarbons'1
Fuel
Fuel Code
Methanol, vol. 9
Ethanol, vol. %
TBA, vol. %
RVP, psi
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HC
Total Hydrocarbons
Fuel
Fuel Code
Methanol, vol.
Ethanol, vol. %
TBA, vol. %
RVP, psi
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HC
Total Hydrocarbons
aND - none detected, less than 0.02 g/test
bNR - not required
cTotal FID hydrocarbons corrected for alcohol content
dSum of alcohols and non-oxygenated hydrocarbons
Low RVP-Low Aromatic
EM-616-F
9.2
5.3
2.7
ND*
NRb
NR.
18.2
18.2
EM-642-F
4.75
4.75
8.5
Evaporative
1.6
0.6
0.5
NR
0.2
8.5
9.2
EM-643-F
5.00
2.50
8.4
Results, g/test
1.9
0.7
0.7
<0.1
NR
10.4
11.1
EM-644-F
5.00
9.2
2.2
0.7
2.2
NR
NR
11.3
13.5
High RVP-Low Aromatic
EM-641-F
11.6
10.3
3.1
0.4
NR"
NR
23.9
24.3
EM-638-F
4.75
4.75
11.6
Evaporative
8.3
4.1
3.4
NR
0.3
27.2
30.9
EM-639-F
5.00
2.50
11.9
Results, g/test
10.3
3.3
3.2
0.1
NR
21.1
24.4
EM-640-F
5.00
12.0
6.8
3.2
4.5
NR
NR
22.5
27.0
Low RVP-High Aromatic
EM-645-F
9.4
7.2
1.5
0.1
NR
NR
15.5
15.5
EM-646-F
4.75
4.75
8.8
Evaporative
2.5
1.2
1.1
NR
0.2
8.9
10.2
EM-647-F
5.00
2.50
9.1
Results, a/test
3.0
1.5
2.0
0.1
NR
10.7
12.8
EM-648-F
5.00
9.6
3.4
1.6
2.1
NR
NR
12.8
14.8
19
-------
TABLE 6. AVERAGE DIURNAL EVAPORATIVE EMISSIONS,
WORK ASSIGNMENT 18 STUDY
EM-697-F EM-690-F EM-702-F EM-70Q-F EM-703-F EM-701-F EM-698-F
Fuel Code
Volatility Class
Methanol, Vol%
Ethanol, Vol%
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
C4 Olefins
C5-C6 Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCe
Total Hydrocarbons*
a<0.01, less than 0.005 g/test and greater than 0.001 g/test
^none detected, for individual hydrocarbons, < 0.001 g/test
cnone detected, for methanol and ethanol, <0.01 g/test
^not required
eTotal FID hydrocarbons corrected for alcohol content
*Sum of alcohols and non-oxygenated hydrocarbons
E
14.0
<0.0ia
<0.01
<0.01
NDb
0.19
0.01
0.02
0.18
1.84
3.27
1.47
0.21
0.01
0.03
0.04
0.09
0.04
0.02
0.06
0.01
0.39
0.85
NDC
NRd
9.0
9.0
D C (Indolene) C D
5.0 5.0
2.5 2.5
12.0 10.9 9.2 11.5 13.2
Average Evaporative Results, s/test
0.02
<0.01
0.03
ND
0.31
0.03
0.09
0.11
2.01
5.04
2.64
1.16
0.09
0.09
0.11
0.43
0.23
0.18
0.13
0.03
0.39
1.26
ND
NR
13.9
13.9
<0.01
ND
0.01
ND
0.33
0.01
0.18
0.18
3.08
7.52
4.87
2.11
0.15
0.15
0.22
0.81
0.27
0.39
0.22
0.05
0.74
2.08
ND
NR
22.8
22.8
<0.01
<0.01
0.02
ND
0.15
0.03
0.02
0.25
0.48
8.11
3.40
0.78
0.12
0.05
0.28
0.26
0.15
0.08
0.08
0.14
0.35
0.75
ND
NR
15.8
15.8
<0.01
ND
<0.01
ND
0.15
0.01
0.24
0.24
2.87
8.39
6.65
3.18
0.23
0.19
0.32
1.26
0.73
0.63
0.35
0.09
0.67
3.25
2.89
0.31
28.0
31.2
ND
ND
<0.01
ND
0.15
0.01
0.10
0.10
1.26
3.33
1.94
0.87
0.07
0.06
0.08
0.33
0.21
0.15
0.10
0.03
0.37
0.96
0.58
ND
10.4
11.0
E
5.0
2.5
15.0
<0.01
ND
<0.01
ND
0.13
0.01
0.03
0.09
1.71
3.20
1.49
0.29
0.01
0.08
0.03
0.09
0.06
0.03
0.04
0.02
0.35
0.83
0.37
ND
8.2
8.6
20
-------
CD
cn
a
CD
cr
cr
CJ
a
cr
a
^
:c
a
LU
i
cn
a:
a
h-
LU
CD
cr
cr
LU
cr
28
24
20
16
12
8
4
n
X
+ A
-
_I_
T^
+ +
^V
\J/
A + GRSOLINE
A D METHRNOL/TBR BLEND
D D A METHRNOL/ETHRNOL BLEND
* METHRNOL BLEND
-
6
8
10
RVP.PSI
12
14
FIGURE 9. PLOT OF TOTAL SHED HYDROCARBONS VERSUS FUEL RVP FOR THE
60-84°F DIURNAL TESTS
-------
In the Work Assignment 18 investigations, which utilized three diurnal
temperature rise scenarios and three volatility classes of fuel, total SHED
hydrocarbons were found to increase with increasing diurnal temperatures despite a
decrease in corresponding fuel volatility. This trend is illustrated in Figure 10,
which groups the fuels as to diurnal test temperatures. The alcohol blend EM-703-F
gave higher SHED hydrocarbons than its corresponding lower RVP base fuel, EM-
702-F. The remaining two blends, EM-701-F and EM-698-F, however, gave lower
SHED hydrocarbons than their corresponding base fuels, EM-690-F and EM-697-F.
Total hydrocarbon emissions appeared to follow RVP trends in the Work
Assignment 12 investigations, with higher RVP fuels giving higher total
hydrocarbons. For the higher RVP fuels, the gasoline and gasoline/alcohol blends
gave similar total hydrocarbon levels; however, at the lower RVP, total hydrocarbon
levels were generally lower for the gasoline/alcohol blends than for the gasoline
blends. Variations in fuel aromatic content did not appear to alter total
hydrocarbon levels as significantly as RVP variations. These observations are
illustrated in Figure 11.
2. Individual Hydrocarbons
Individual hydrocarbons, with one to six carbons plus the seven-carbon
compounds toluene and 2,4-dimethylpentane, were characterized in the Work
Assignment 18 program. Saturated hydrocarbons and G£ and 03 olefins were
quantified individually in this program, whereas the 04 to C(, unsaturated olefins
were grouped as a total for 04 and a total for 05.5. In the Work Assignment 12
program, only butane and isobutane were characterized.
In general, the individual hydrocarbons followed the same trends as the
total hydrocarbons in the Work Assignment 18 study. Methane, ethane, ethylene,
and propylene were found in small but measurable quantities in a number of the
SHED tests. Acetylene was not detected in any of the samples analyzed. Propane
was detected in all of the SHED tests, with higher levels found in the tests with the
base gasoline fuels than in the tests with the corresponding alcohol blend fuels. This
result was likely due to the partial removal of some of the base fuel light ends
during the preparation of the alcohol blends. In order to further evaluate the
effects of alcohol content and diurnal temperature on the composition of the SHED
hydrocarbons, the percentages of the total non-oxygenated hydrocarbons for
selected individual hydrocarbons were calculated and are presented in Table 7.
Benzene was found to be one percent or less of the total hydrocarbons for all seven
test fuels. The highest benzene percentage occurred with alcohol blend EM-701-F
(1.0%) and the lowest withlndolene (0.13%).
Indolene, however, gave the highest percentage of toluene in the SHED
hydrocarbons for the seven fuels. Fuels EM-690-F, EM-702-F, EM-703-F, and EM-
701-F, which were prepared from similar base stock fuels, all had similar benzene
and toluene percentages. Isobutane, n-butane, isopentane, and pent an e made up the
majority of the total SHED non-oxygenated hydrocarbons, with combined
percentages ranging from 71.2% for fuel EM-701-F to 81.6% for fuel EM-698-F.
Indolene, EM-700-F, had relatively low levels of isobutane, 3.0% compared to a
range of 10.3% to 20.9% for the remaining fuels; but high levels of n-butane, 51.3%
compared to a range of 30.0% to 39.0% for the remaining fuels. Generally the
alcohol blends had lower levels of isobutane and n-butane in the total non-
22
-------
CD
CD
CD
m
on
-
IE
a
LJJ
cn
_
CE
h-
a
LLI
CD
-------
CD
CD
Z
o
m
cr
cr
u
CD
cr
a
a
LLJ
CD
_
cr
o
LU
CD
CE
cr
LJJ
>
CE
Gasoline
Methanol/TBA Blend
Methanol/Ethanol Blend
Methanol Blend
LOW RVP-LOW RRO HIGH RVP-LOW PRO LOW RVP- HIGH RRO
FUEL PROPERTIES
FIGURE 11. TOTAL SHED HYDROCARBON RESULTS GROUPED AS TO RVP AND
AROMATIC CONTENT OF THE TEST FUEL
-------
TABLE 7. INDIVIDUAL HYDROCARBONS AS PERCENTAGE OF TOTAL
NON-OXYGENATED HYDROCARBONS, WORK ASSIGNMENT 18 STUDY
Fuel Code
EM-697-F EM-690-F EM-702-F EM-700-F EM-703-F EM-701-F EM-698-F
Volatility Class
Methanol, Vol%
Ethanol, Vol%
RVP, psi
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
Cyclopentane
Cfc Saturates
2,4-dim ethylpentane
C4 Olefins
Cs_6 Olefins
E
14.0
0.2
2.0
20.4
36.3
16.3
2.3
0.3
2.9
0.1
4.3
9.4
D
12.0
Average
0.6
0.8
14.5
36.3
19.0
8.3
0.6
8.4
0.2
2.8
9.1
C
10.9
dndolene)
9.2
Evaporative Results,
0.8
0.8
13.5
33.0
21.4
9.3
0.7
9.0
0.2
3.2
9.1
0.1
2.7
3.0
51.3
21.5
4.9
0.3
6.1
1.5
2.2
4.7
C
5.0
2.5
11.5
percent of
0.9
0.9
10.3
30.0
23.8
11.4
0.7
12.6
0.3
2.4
11.6
D
5.0
2.5
13.2
total HC
1.0
1.0
12.1
32.0
18.7
8.4
0.6
9.0
0.3
3.6
9.2
E
5.0
2.5
15.0
0.4
1.1
20.9
39.0
18.2
3.5
1.0
3.2
0.2
4.3
10.1
25
-------
oxygenated hydrocarbons than their corresponding base fuels (light end removal
during blend preparation and/or dilution by alcohol addition), however, many of the
higher boiling C$ and Cfc compounds were generally present in higher percentages in
the alcohol blend vapors than in the base gasoline vapors. The percentage of olefins
in the SHED non-oxygenated hydrocarbons was found to be relatively high (7-14%),
possibly a result of higher concentrations of fuel olefins in the 04 to Cg fuel
fraction as compared to the entire fuel.
Butane and isobutane SHED levels in the Work Assignment 12 study were found
to be directly related to the butane and isobutane levels in the fuels. Fuels EM-642-
F, EM-643-F, and EM-644-F were prepared by bubbling nitrogen through fuel EM-
616-F to remove the lower-boiling hydrocarbons (such as n-butane and isobutane)
before blending with the alcohols. The resulting lower levels of butane and
isobutane in these fuels are reflected by the lower levels of butane and isobutane in
the SHED tests. In addition, the ratio of butane to isobutane in these fuels appears
to have been altered in the bubbling process, because the ratio of butane to
isobutane in the SHED was higher for fuels EM-642-F, EM-643-F, and EM-644-F (3
to 1) than for the base fuel, EM-616-F (2 to 1). Isobutane is more volatile than
butane (n-butane b.p., 0°C; isobutane b.p. -12°C), and its preferential loss in the
bubbling process is expected. Fuel EM-641-F was prepared by the addition of n-
butane to fuel EM-616-F, but no isobutane was added. This relative increase in n-
butane for fuel EM-641-F is reflected in the n-butane and isobutane SHED data in
Table 7. Fuels EM-638-F, EM-639-F, and EM-640-F were prepared by the addition
of alcohols to base fuel EM-616-F. Fuels EM-645-F, EM-646-F, EM-647-F, and EM-
648-F were prepared from a common aromatic-enriched blend stock, and gave
similar levels of isobutane in the SHED. Fuel EM-645-F was enriched in n-butane to
increase its RVP. This n-butane addition is once again reflected by the n-butane
levels in the SHED. In Work Assignment 12, butane accounted for 18.3 to 46.5
percent of the total SHED non-oxygenated hydrocarbons, while isobutane accounted
for 6.2 to 15.6 percent of the total SHED non-oxygenated hydrocarbons.
3. Alcohols
Methanol, methanol/ethanol, and methanol/TBA blends with gasoline
were evaluated in the Work Assignment 12 study, while only methanol/ethanol
blends were evaluated in the Work Assignment 18 study. In the Work Assignment 12
study, the higher-RVP fuels were found to give higher levels of methanol in the
diurnal SHED tests than the lower-RVP fuels. The high-RVP fuels EM-638-F, EM-
639-F, and EM-640-F gave SHED methanol levels ranging from 3.2 to 4.5
grams/test. The low-RVP fuels EM-642-F, EM-643-F, EM-644-F, EM-646-F, EM-
647-F, and EM-648-F, gave SHED methanol levels ranging from 0.5 to 2.2
grams/test. All these fuels contained approximately 5 percent methanol. Methanol
was detected in the SHED vapors for the testing of all three gasoline/alcohol blends
in the Work Assignment 18 study. As was the case for the total hydrocarbons, the
SHED methanol levels increased with increasing diurnal test temperatures despite a
decrease in fuel volatility.
Levels of ethanol and TEA in the diurnal tests were much lower than the
corresponding levels of methanol in Work Assignment 12 evaluations. As was the
case for methanol, the higher-RVP fuel, EM-638-F, gave higher TBA levels than the
lower RVP fuels, EM-642-F and EM-646-F (0.3 g/test vs 0.2 and 0.2 g/test). The
relationship between ethanol levels in the SHED and the fuel RVP was less apparent
26
-------
than for the other two alcohols. As was noted for SHED total hydrocarbon levels,
variations in fuel aromatic content did not appear to alter the alcohol levels as
significantly as the RVP. In Work Assignment 18 evaluations, ethanol was detected
only during the SHED testing of fuel EM-703-F at 60-84°F. This result indicates
that higher fuel temperatures are needed to vaporize appreciable qualities of
ethanol into the SHED.
B. High-Temperature Tests (160 ± 10°F)
Duplicate high-temperature SHED tests were conducted in the Work
Assignment 12 investigation with 12 gasolines and gasoline-alcohol blends. These
tests were conducted to simulate vehicle hot-soak losses, and used 125 ml of fuel
heated with a 160°F water bath. Average test results are tabulated by fuel RVP and
aromatic content in Table 8. Individual test results are presented in Appendix B. As
was the case for the diurnal tests, the higher-RVP fuels, in general, gave higher
levels of total hydrocarbons. As expected, however, the total hydrocarbon levels
correlated more closely with the distillation curves (heating the fuel to 160°F in the
flask is actually a partial distillation of the fuel, with the fraction of the fuel boiling
below 160°F being "distilled" into the SHED). Fuel EM-645-F, which has only 16%
of its volume distilling below 160°F, gave the lowest total hydrocarbon level; while
fuel EM-639-F, which has 39% of its volume distilling below 160°F, gave the highest
total hydrocarbon level. A linear regression plot of the total SHED hydrocarbons
versus the volume of fuel distilling below 160°F for each of the twelve test fuels
gave an r^ value of 0.91. In contrast, a linear regression plot of SHED hydrocarbons
versus RVP gave an r^ of only 0.3.
Butane and isobutane levels in the SHED were, as in the diurnal tests,
dependent on their concentration in the fuel. The ranges of butane (1.0 to 4.5
grams) and isobutane (0.2 to 1.0 grams) found in the high temperature SHED tests
were not as large as for the diurnal tests (1.6 to 10.3 for butane and 0.5 to 4.1 for
isobutane) due to the smaller quantities of fuel used in the tests.
The levels of alcohols in the high-temperature SHED tests were higher for the
higher-RVP fuels (3.9 to 4.2 g methanol/test, 0.6 g ethanol/test, and 1.3 g TBA/test)
than for the lower-RVP fuels (1.7 to 3.3 g methanol/test,<0.01 to 0.2 g ethanol/test,
and 0.3 to 0.9 g TBA/test). For the higher-RVP fuels, it appears that the amount of
methanol found in the SHED is almost equivalent to the amount of methanol in the
125 ml of test fuel. Fuels EM-638-F, EM-639-F, and EM-640-F all contain
approximately 5% (EM-638-F contains 4.75%) by volume methanol, or 6.25 ml of
methanol. Assuming that methanol has a density of 0.79 g/ml, each test fuel
contains approximately 4.9 grams of methanol per 125 ml of fuel. The average
SHED methanol value for fuels EM-638-F, EM-639-F, and EM-640-F (4.0 grams)
accounts for more than 80% of the fuel methanol. The average SHED methanol
value for the lower-RVP fuels (2.5 grams) accounts for only approximately 60% of
the fuel methanol. The levels of ethanol and TEA in the SHED were much lower
than the levels of methanol in the SHED, accounting for only 1% to 26% of the fuel
ethanol and 6% to 28% of the fuel TEA. Changes in the amounts of alcohol in the
SHED as a result of variations in fuel aromatic content were more variable and of
much smaller magnitude than changes resulting from variations in fuel RVP.
27
-------
TABLE 8. AVERAGE HIGH TEMPERATURE EVAPORATIVE EMISSIONS
Fuel
Fuel Code
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCC
Total Hydrocarbons'1
Fuel
Fuel Code
Methanol, vol. %
Ethanol, vol. %
TBA, vol. %
RVP, psi
Percent Fuel Distilled at 16Qop (D-86)
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HC
Total Hydrocarbons
Fuel
Fuel Code
Methanol, vol. %
Ethanol, vol. %
TBA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HC
Total Hydrocarbons
Low RVP-Low Aromatic
EM-616-F
9.2
Z6
2.6
1.0
NDa
NRb
NR
8.1
8.1
EM-642-F
4.75
4.75
8.5
31
Evaporative
1.0
0.2
2.5
NR
0.9
15.0
18.3
EM-643-F
5.00
2.50
8.4
32
Results, a/test
1.0
0.3
3.3
<0.1
NR
14.9
18.1
EM-644-F
5.00
9.2
27
1.1
0.3
2.6
NR
NR
12.3
14.9
Hiah RVP-Low Aromatic
EM-641-F
11.6
30
4.5
0.9
0.2
NR
NR
15.8
16.0
EM-638-F
4.75
4.75
11.6
37
Evaporative
2.5
0.8
3.9
NR
1.3
17.1
22.2
EM-639-F
5.00
2.50
11.9
39
Results, e/test
2.6
0.8
3.9
0.6
NR
18.9
23. 5
EM-640-F
5.00
12.0
34
2.8
1.0
4.2
NR
NR
15.4
19.5
Low RVP-Hiah Aromatic
EM-645-F
9.4
16
2.4
0.4
ND
NR
NR
5.9
5.9
EM-646-F
4.75
4.75
8.8
24
Evaporative
1.5
0.5
1.7
NR
0.3
9.9
11.9
EM-647-F
5.00
2.50
9.1
28
Results, 2/test
1.6
0.5
2.6
0.2
NR
11.5
14.2
EM-648-F
5.00
9.6
24
1.4
0.5
2.1
NR
NR
9.8
11.8
aND - none detected, less than 0.02 g/test
bNR - not required
cTotal FID hydrocarbons corrected for alcohol content
of alcohols and non-oxygenated hydrocarbons
28
-------
W. QUALITY ASSURANCE
The Quality Assurance (QA) guidelines addressed in the QA reports for Work
Assignments 12 and 18 of EPA Contract 68-03-3192 were followed in performing the
work for this program. Quality assurance associated with fuel handling, SHED
procedures, and sample analyses are described in the following paragraphs.
All fuel containers used in the program were kept well sealed and stored in a
refrigerated facility (40°F) adjacent to the Emissions Laboratory high bay test area
(location of SHED) until needed. All necessary fuel transfers were performed while
the fuel was at or near 40°F to minimize any loss of fuel vapors. The
gasoline/alcohol blends were prepared from the base gasolines at the Energy
Conversion and Combustion Technology facility. All blending and associated fuel
handling was conducted in their refrigerated facility (also at 40°F). Fuel samples of
each gasoline or gasoline/alcohol blend were taken for RVP determinations from the
same containers as the fuel used in the SHED tests.
The SHED bag sampling technique used in this program for the analysis of
alcohols was validated in the Work Assignment 12 study. The validation experiments
were conducted to determine the magnitude of alcohol losses during typical SHED
tests. The effect of humidity on alcohol sampling was also investigated in the
validation experiments. The test sequence followed in these experiments is
summarized in Table 9.
TABLE 9. SHED VALIDATION EXPERIMENTS
Sequence
SHED purged and checked for alcohol background
20 g of 50 vol. % methanol/50 vol. % TBA placed in a clean beaker
Beaker placed in the SHED and heated at a rate such that all the
alcohol was evaporated within 60 minutes
4 Heating blankets placed in the SHED to simulate the presence of a
vehicle
5 After all of the alcohol had been vaporized, a bag sample was obtained
from the SHED and analyzed for methanol and TBA concentrations
6 Percent recovery determined for methanol and TBA
7 SHED purged
8 SHED checked for background methanol and TBA
9 Steps 1-6 repeated at higher relative humidity
29
-------
This test sequence was conducted in duplicate, and the results reported to the
Project Officer before any SHED testing with fuel was conducted. Table 10 lists the
results of this testing. Methanol recoveries were found to be on the order of 98 ± 8
percent, while TBA recoveries were lower at 82 ± 11 percent. Increases in SHED
humidity did not result in decreases in alcohol recoveries. In fact, the reverse was
found, with higher alcohol recoveries occurring in the higher relative humidity tests.
SHED and bag cart (for FID total hydrocarbons) calibrations were performed
using procedures and equipment specified in the Federal Register, and are available
for inspection. The reliability of the SHED bag sampling system was checked by
introducing a known concentration of propane (for total hydrocarbon analysis) into
the sampling port on the inside of the SHED and collecting a bag sample for
analysis. A 670 ppmC propane standard was introduced into the probe inlet,
collected in a SHED sample bag, and analyzed using a FID total hydrocarbon
analyzer. This analysis gave a total hydrocarbon reading of 667 ppmC, which is
within 0.5% of the standard concentration. In a second check, a 380 ppmC propane
standard gave 380, 381, and 378 ppmC when analyzed at the SwRI bag cart on three
separate test days.
For the quantification of butane and isobutane in the Work Assignment 12
investigations, butane standards, named using the SwRI bag cart HC FID analyzer
and published FID response factors, were run at the beginning and end of each test
day. The GC-FID instrument for the analysis of butane and isobutane gave good
day-to-day repeatability. The peak area for a 102.5 ppmC butane standard gave
only a 4 percent variation over an 8-day period (all injections). To check the
reliability of the SHED bag sampling system for butane, two butane standards named
as 110 and 167 ppmC, were introduced at the SHED sampling point and were found
to contain 117 and 170 ppmC, respectively, when analyzed along with other butane
test samples.
For analysis, alcohol samples were collected in water and stored in
polypropylene sample bottles until the appropriate analyses could be conducted.
Alcohol standards and samples have been found to be stable for several months when
well sealed in polypropylene sample bottles. In Work Assignment 12, alcohol
samples were found to decrease in concentration by only 5 percent when stored for a
six-month period. The alcohol analyses for Work Assignment 18 were generally
conducted within two to four weeks of sample collection in water.
For Work Assignment 12, methanol analyses of the diurnal and high-
temperature tests with fuels EM-638-F, EM-639-F, EM-640-F, EM-641-F, EM-642-F,
and EM-643-F were completed immediately after the samples were collected. Due
to program time constraints, only the first bubbler of each test bubbler set (two
bubblers are used to collect each alcohol sample with the first bubbler containing
approximately 90% of the total sample) was analyzed immediately after collection
for methanol for the diurnal and high-temperature tests with fuels EM-644-F, EM-
646-F, EM-647-F, and EM-648-F. The second bubbler of each set and the associated
background samples (both bubblers in each set) as well as all of the samples
generated in the tests with fuels EM-616-F and EM-645-F were analyzed for
methanol approximately six months after sample collection. All ethanol and TBA
analyses for tests conducted with fuels EM-642-F and EM-646-F were also
conducted at this time. TBA analyses for tests conducted with fuel EM-638-F were
conducted in part during both time periods. Diurnal test samples (Tests 1 and 2,
30
-------
TABLE 10. VALIDATION RESULTS FOR ALCOHOL BAG SAMPLING TECHNIQUE
AT VARYING RELATIVE HUMIDITY LEVELS
Alcohol Evaporated, g
Methanol TEA
Alcohol Recovered,g Recovery»
SHED Background
63% Relative Humidity
SHED Background
SHED Background
68% Relative Humidity
SHED Background
SHED Background
70% Relative Humidity
SHED Background
SHED Background
85% Relative Humidity
SHED Background
SHED Background
86% Relative Humidity
SHED Background
SHED Background
90% Relative Humidity
SHED Background
10.90
10.05
10.03
10.04
10.88
10.16
10.01
10.14
Methanol
ND
10.71
0.11
0.04
8.89
0.07
__
ND
9.80
0.06
0.02
10.82
0.34
__
TEA
ND
8.54
0.06
0.06
a
0.07
ND
6.81
0.03
ND
b
0.06
ND
8.89
0.08
ND
9.32
0.08
Average
Methanol
_
98
_
88
__
__
98
__
108
_ _
98 ±8
TEA
78
w.
a
__
67
___
b
__
89
_«.
92
82~±~il
a Test results atypically high, 116% recovery; experiment repeated at 70% relative humidity
b Test results atypically low, 40% recovery; experiment repeated at 90% relative humidity
31
-------
Bubblers 1 and 2) and high-temperature bubbler 1 samples from Test 1 (both sample
and background) were analyzed immediately after collection, with the remainder of
the samples being analyzed at the later date.
To check the stability of actual samples in Work Assignment 12, four samples
analyzed in September, 1985 were reanalyzed in March, 1986. The results of these
analyses are listed below:
Sample Test Type
1
2
3
4
Fuel
Test
No.
Diurnal
High-Temp.
High-Temp.
Diurnal
EM-642-F
EM-643-F
EM-643-F
EM-647-F
2
1
2
1
Sept. March
Bubbler Analysis Analysis
(1 or 2) jug/ml us/ml
1 61 64
1 264 241
1 297 270
1 230 212
Percent
Difference
Average -5.216.7%
These analyses show that during the period between September, 1985 and March
1986 the concentration in the bubblers decreased, on the average, approximately 5
percent. These results should be taken into consideration when comparing results
for samples analyzed during the two time periods. In most cases, this decrease in
concentration should not greatly affect the methanol results as the majority of the
bubbler 1 samples, which contain 90% of the sample, were analyzed in September.
Injection repeatability for each of the alcohol standards used to bracket the
test samples was determined during both work assignments. This repeatability was
determined by averaging standard areas from an uninterrupted series of standard
injections actually used to bracket sample runs (one standard, two samples, one
standard, two samples, etc.).
The results of the Work Assignment 12 injection repeatability determinations
are presented below:
Standard
Methanol
Ethanol
TBA
Concen.
ppm
791
79.1
39.6
78.9
78.9
39.5
Number of
Analyses in
Uninterrupted
Sequence
14
7
8
12
4
8
Average
Area
23069
33707
129.5(peak
height, mm)
28615
23915
31556
Standard
Deviation
in Area
775
2296
5.2 (peak
height, mm)
921
385
1201
Percent
Deviation
3.4
6.8
4.0
3.2
1.6
3.8
32
-------
Sample peak heights were found to be more reliable than peak areas when using the
39*6 ppm methanol standard, and were therefore used in place of the area to
calculate sample concentrations. A linearity check for peak heights in the 0.4 to
39.6 ppm range was conducted and found to be acceptable, with r^ = 0.993 for the
plotted line.
Injection repeatability was found to be somewhat better in Work Assignment
18 studies than in Work Assignment 12 studies, with the percent deviation less than
five percent for all of the alcohol standards and less than two percent for the higher
concentration standards. The results for the Work Assignment 18 injection
repeatability determinations are presented below:
Number of
Analyses in Standard
Cone. Uninterrupted Average Deviation Percent
Standard ppm Sequence Area in Area Deviation
Methanol 7.91 9 3407 170 4.7
15.8 5 5865 269 4.6
79.1 5 10452 130 1.2
791 3 13308 70 0.5
Ethanol 15.8 11 5553 56 1.0
78.9 5 14465 132 0.9
For the GC-FID analysis of the Cj-C3 hydrocarbons, benzene, and toluene,
standard samples from a compressed gas cylinder containing known concentrations
of methane, ethylene, ethane, acetylene, propane, propylene, benzene, and toluene
were run at the beginning and end of each test day to bracket samples analyzed that
day. In all, 10 sets of standard analyses (total of 20 analyses) were conducted during
the course of the program. With the exception of acetylene, the day-to-day
repeatability (as percent deviation for the 20 analyses) ranged from 4.9% for
methane to 8.6% for toluene. The repeatabilities for the standards run on the same
day were generally 1 to 1.5% better for each of the individual hydrocarbons. The
day-to-day repeatability for the acetylene standard was not good, and has been used
in this program only as a means to determine the presence or absence of acetylene
in the SHED samples. Acetylene was not detected in any of the samples analyzed.
For the GC-FID analysis of the C^-Cfr hydrocarbons and 2,4-dimethylpentane,
a standard bag containing 13 individual hydrocarbons (isobutane, n-butane,
isopentane, pentane, 2,2-dimethylbutane, cyclopentane, 2-methylpentane, 3-
methylpentane, hexane, methylcyclopentane, 2,4-dimethylpentane, and benzene) in
the approximate ratio observed in the SHED samples was run at the beginning and
end of each test day to bracket the samples. This standard bag was named against a
known propane standard using the SwRI bag cart (total hydrocarbons) and found to
contain 995 ppmC. The summation of all the peak areas in the individual
hydrocarbon analysis divided by the bag cart ppmC gave the average GC response
factor (area per ppmC) which was used to calculate an individual hydrocarbon
sample concentration. The percent deviation for standards run on the same day was,
on the average, 6.1% (total area basis).
33
-------
APPENDIX A
DIURNAL EVAPORATIVE EMISSIONS
-------
TABLE A-l. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-616-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
9.2
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCC
Total Hydrocarbons*1
Test 1
5.9
3.0
NDa
NRb
NR
18.3
18.3
Test 2
4.6
2.3
ND
NR
NR
18.0
18.0
Average
5.3
2.7
ND
NR
NR
18.2
18.2
aND - none detected, less than 0.02 g
^NR - not required
cTotal FID hydrocarbons corrected for alcohol content
"Sum of alcohols and non-oxygenated hydrocarbons
A-2
-------
TABLE A-2. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-64Z-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
4.75
4.75
8.5
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
1.5
0.5
0.4
NRa
0.2
8.2
8.8
Test 2
1.7
0.6
0.6
NR
0.2
8.8
9.6
Average
1.6
0.6
0.5
NR
0.2
8.5
9.2
aNR - not required
*>Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-3
-------
TABLE A-3. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-643-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
5.00
2.50
8.4
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCC
Total Hydrocarbons^
Test 1
1.9
0.7
0.5
10.4
10.9
Test 2
1.9
0.7
0.9
NDa
NR
10.4
11.3
Average
1.9
0.7
0.7
<0.1
NR
10.4
11.1
aND - none detected, less than 0.02 g
*>NR - not required
cTotal FID hydrocarbons corrected for alcohol content
of alcohols and non-oxygenated hydrocarbons
-------
TABLE A-4. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-644-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TBA, vol. %
RVP, psi
5.00
9.2
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.0
0.7
2.1
NRa
NR
10.5
12.6
Test 2
2.3
0.8
2.3
NR
NR
12.0
14.3
Average
2.2
0.7
2.2
NR
NR
11.3
13.5
aNR - not required
*>Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-5
-------
TABLE A-5. DIURNAL EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-641-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
11.6
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
10.7
3.3
0.4
NR*
NR
25.2
25.6
Test 2
9.8
2.9
0.3
NR
NR
22.6
22.9
Average
10.3
3.1
0.4
NR
NR
23.9
24.3
aNR - not required
"Total FID hydrocarbons corrected for alcohol content
C8um of alcohols and non-oxygenated hydrocarbons
A-6
-------
TABLE A-6. DIURNAL EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-638-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
4.75
4.75
11.6
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
8.7
4.3
3.3
NRa
0.4
29.6
33.3
Test 2
7.8
3.9
3.4
NR
0.3
24.7
28.4
Average
8.3
4.1
3.4
NR
0.3
27.2
30.9
aNR - not required
"Total FID hydrocarbons corrected for alcohol content
cSuin of alcohols and non-oxygenated hydrocarbons
A-7
-------
TABLE A-7. DIURNAL EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-639-F
(WORK ASSIGNMENT 12)
Methanol, vol. % 5.00
Ethanol, vol. % 2.50
TEA, vol. %
RVP, psi 11.9
Evaporative Results, g/test
Test 1 Test 2 Average
Butane 10.7 9.8 10.3
Isobutane 2.9 3.6 3.3
Methanol 2.6 3.7 3.2
Ethanol ND* 0.2 0.1
TEA NRb NR NR
Total Non-oxygenated HCC 19.4 22.8 21.1
Total Hydrocarbons*1 22.0 26.7 24.4
aND - none detected, less than 0.02 g
^NR - not required
cTotal FID hydrocarbons corrected for alcohol content
"Sum of alcohols and non-oxygenated hydrocarbons
A-8
-------
TABLE A-8. DIURNAL EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-640-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
5.00
12.0
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
7.6
3.5
4.6
NRa
NR
21.8
26.4
Test 2
6.0
2.9
4.4
NR
NR
23.2
27.6
Average
6.8
3.2
4.5
NR
NR
22.5
27.0
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-9
-------
TABLE A-9. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-645-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
9.4
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
7.0
1.4
0.1
NR*
NR
15.4
15.5
Test 2
7.3
1.5
NR
NR
15.5
15.5
Average
7.2
1.5
0.1
NR
NR
15.5
15.5
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-10
-------
TABLE A-10. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-646-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
4.75
4.75
8.8
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.4
1.1
1.0
NRa
0.2
8.5
9.7
Test 2
2.6
1.2
1.1
NR
0.2
9.3
10.6
Average
2.5
1.2
1.1
NR
0.2
8.9
10.2
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-ll
-------
TABLE A-ll. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-647-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
5.00
2.50
9.1
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.9
1.4
2.5
0.1
NRa
10.7
13.3
Test 2
3.0
1.5
1.5
0.1
NR
10.6
12.2
Average
3.0
1.5
2.0
0.1
NR
10.7
12.8
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-12
-------
TABLE A-1Z. DIURNAL EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-648-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
5.00
9.6
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
3.2
1.5
1.8
NR
12.5
14.3
Test 2
3.5
1.7
2.3
NR
NR
13.0
15.3
Average
3.4
1.6
2.1
NR
NR
12.8
14.8
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
A-13
-------
TABLE A-13. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-697-F
(WORK ASSIGNMENT 18)
14.0
Evaporative Results, g/test
Volatility Class
Methanol, Vol %
Ethanol, Vol %
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
64 Olefins
05-05 Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCe
Total Hydrocarbons*
a<0.01, less than 0.005 g/test and greater than 0.001 g/test
^none detected, for individual hydrocarbons, <0.001 g/test
cnone detected, for methanol and ethanol, <0.01 g/test
^not required
eTotal FID hydrocarbons corrected for alcohol content
*Sum of alcohols and non-oxygenated hydrocarbons
Test 1
<0.0ia
<0.01
ND
ND
0.20
0.02
0.03
0.24
1.92
3.44
1.56
0.22
0.01
0.03
0.04
0.10
0.05
0.02
0.03
0.01
0.38
0.90
NDC
NRd
9.5
9.5
Test 2
NDb
ND
<0.01
ND
0.18
0.01
0.02
0.12
1.75
3.10
1.38
0.20
0.02
0.02
0.04
0.08
0.04
0.02
0.09
0.01
0.40
0.79
ND
NR
8.5
8.5
Average
<0.01
<0.01
<0.01
ND
0.19
0.01
0.02
0.18
1.84
3.27
1.47
0.21
0.01
0.03
0.04
0.09
0.04
0.02
0.06
0.01
0.39
0.85
ND
NR
9.0
9.0
A-14
-------
TABLE A-14. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-690-F
(WORK ASSIGNMENT 18)
D
1Z.O
Evaporative Results, g/test
Volatility Class
Methanol, Vol %
Ethanol, Vol %
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
4 Olefins
Cs-Cfc Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCe
Total Hydrocarbons*
anone detected, for individual hydrocarbons, < 0.001 g/test
b<0.01, less than 0.005 g/test and greater than 0.001 g/test
cnone detected, for methanol and ethanol, < 0.01 g/test
"not required
eTotal FID hydrocarbons corrected for alcohol content
*Sum of alcohols and non-oxygenated hydrocarbons
Test 1
0.02
ND*
0.02
ND
0.25
0.02
0.07
0.09
1.52
3.58
1.87
0.83
0.08
0.06
0.08
0.31
0.14
0.13
0.09
0.02
0.24
0.87
NDC
NRd
10.6
10.6
Test 2
0.03
<0.0lb
0.03
ND
0.38
0.03
0.12
0.13
2.50
6.51
3.41
1.49
0.10
0.12
0.14
0.56
0.31
0.24
0.17
0.04
0.54
1.64
ND
NR
17.1
17.1
Average
0.02
<0.01
0.03
ND
0.31
0.03
0.09
0.11
2.01
5.04
2.64
1.16
0.09
0.09
0.11
0.43
0.23
0.18
0.13
0.03
0.39
1.26
ND
NR
13.9
13.9
A-15
-------
TABLE A-15.
DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-70Z-F
(WORK ASSIGNMENT 18)
10.9
Evaporative Results, g/test
Volatility Class
Methanol, Vol %
Ethanol, Vol %
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
4 Olefins
C5-C6 Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCe
Total Hydrocarbons*
a<0.01, less than 0,005 g/test and greater than 0.001 g/test
^none detected, for individual hydrocarbons, < 0.001 g/test
cnone detected, for methanol and ethanol, < 0.01 g/test
"not required
eTotal FID hydrocarbons corrected for alcohol content
*Sum of alcohols and non-oxygenated hydrocarbons
Test 1
<0.0ia
NO**
0.01
ND
0.31
0.02
0.18
0.18
3.02
7.48
4.88
2.22
0.15
0.15
0.22
0.84
0.21
0.39
0.22
0.06
0.75
2.08
NDC
NRd
23.1
23.1
Test 2
0.01
ND
0.02
ND
0.34
ND
0.18
0.18
3.14
7.55
4.84
1.99
0.16
0.14
0.23
0.78
0.34
0.39
0.22
0.03
0.74
2.07
ND
NR
22.4
22.4
Average
<0.01
ND
0.01
ND
0.33
0.01
0.18
0.18
3.08
7.52
4.86
2.11
0.15
0.15
0.22
0.81
0.27
0.39
0.22
0.05
0.74
2.08
ND
NR
22.8
22.8
A-16
-------
TABLE A-16. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-700-F
(WORK ASSIGNMENT 18)
(Indolene)
9.2
Evaporative Results, s/test
Volatility Class
Methanol, Vol %
Ethanol, Vol %
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
4 Olefins
Cs-Cfc Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCe
Total Hydrocarbons*
a
0.16
0.02
0.02
0.22
0.51
8.23
3.46
0.80
0.12
0.05
0.29
0.26
0.15
0.09
0.08
0.15
0.36
0.78
NDC
NRd
16.2
16.2
Test 2
<0.01
<0.01
0.02
ND
0.15
0.03
0.02
0.28
0.46
7.99
3.33
0.77
0.12
0.05
0.28
0.26
0.14
0.08
0.07
0.13
0.34
0.71
ND
NR
15.3
15.3
Average
<0.01
<0.01
0.02
ND
0.15
0.03
0.02
0.25
0.48
8.11
3.40
0.78
0.12
0.05
0.28
0.26
0.15
0.08
0.08
0.14
0.35
0.75
ND
NR
15.8
15.8
A-17
-------
TABLE A-17. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-703-F
(WORK ASSIGNMENT 18)
Volatility Class C
Methanol, Vol % 5.0
Ethanol, Vol % 2.5
RVP, psi 11.5
Evaporative Results, g/test
Test 1 Test 2 Average
Individual Hydrocarbons
Methane <0.01a NDb <0.01
Ethylene ND ND ND
Ethane <0.01 <0.01 <0.01
Acetylene ND ND ND
Propane 0.14 0.17 0.15
Propylene 0.01 0.01 0.01
Benzene 0.22 0.26 0.24
Toluene 0.22 0.27 0.24
Isobutane 2.57 3.17 2.87
n-Butane 7.63 9.16 8.39
Isopentane 6.10 7.20 6.65
Pentane 2.91 3.45 3.18
2,2-Dimethylbutane 0.21 0.25 0.23
Cyclopentane 0.14 0.24 0.19
2,3-Dimethylbutane 0.29 0.34 0.32
2-Methylpentane 1.12 1.40 1.26
3-Methylpentane 0.67 0.79 0.73
Hexane 0.57 0.69 0.63
Methylcyclopentane 0.32 0.39 0.35
2,4-Dimethylpentane 0.07 0.11 0.09
C4 Olefins 0.73 0.61 0.67
C5-C6 Olefins 3.22 3.29 3.25
Alcohols
Methanol 2.49 3.28 2.89
Ethanol 0.17 0.44 0.31
Total Non-oxygenated HCC 25.5 30.5 28.0
Total Hydrocarbonsd 28.2 34.2 31.2
a<0.01, less than 0.005 g/test and greater than 0.001 g/test
"none detected, for individual hydrocarbons, <0.001 g/test
cTotal FID hydrocarbons corrected for alcohol content
"Sum of alcohols and non-oxygenated hydrocarbons
A-18
-------
TABLE A-18. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-701-F
(WORK ASSIGNMENT 18)
Volatility Class
Methanol, Vol %
Ethanol, Vol %
RVP, psi
Individual Hydrocarbons
Methane
Ethylene
Ethane
Acetylene
Propane
Propylene
Benzene
Toluene
Isobutane
n-Butane
Isopentane
Pentane
2,2-Dimethylbutane
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-Methylpentane
Hexane
Methylcyclopentane
2,4-Dimethylpentane
C4 Olefins
Cs-C^ Olefins
Alcohols
Methanol
Ethanol
Total Non-oxygenated HCd
Total Hydrocarbons6
anone detected, for individual hydrocarbons, <0.001 g/test
b<0.01, less than 0.005 g/test and greater than 0.001 g/test
cnone detected, for methanol and ethanol, <0.01 g/test
"Total FID hydrocarbons corrected for alcohol content
eSum of alcohols and non-oxygenated hydrocarbons
D
5.0
2.5
13.2
Evaporative Results, g/test
Test 1
NDa
ND
<0.0lb
ND
0.14
0.01
0.10
0.10
1.20
3.06
1.82
0.82
0.07
0.06
0.08
0.32
0.14
0.14
0.09
0.02
0.34
1.00
0.40
NDC
10.0
10.4
Test 2
ND
ND
<0.01
ND
0.16
ND
0.10
0.09
1.32
3.60
2.07
0.92
0.06
0.07
0.09
0.34
0.27
0.16
0.10
0.03
0.40
0.92
0.75
ND
10.7
11.5
Average
ND
ND
<0.01
ND
0.15
0.01
0.10
0.10
1.26
3.33
1.94
0.87
0.07
0.06
0.08
0.33
0.21
0.15
0.10
0.03
0.37
0.96
0.58
ND
10.4
11.0
A-19
-------
TABLE A-19. DIURNAL EVAPORATIVE EMISSIONS, FUEL EM-698-F
(WORK ASSIGNMENT 18)
Volatility Class E
Methanol, Vol % 5.0
Ethanol, Vol % 2.5
RVP, psi 15.0
Evaporative Results, g/test
Test 1 Test 2 Average
Individual Hydrocarbons
Methane <0.0ia NDb <0.01
Ethylene ND ND ND
Ethane <0.01 <0.01 <0.01
Acetylene ND ND ND
Propane 0.14 0.11 0.13
Propylene 0.01 0.01 0.01
Benzene 0.03 0.02 0.03
Toluene 0.14 0.05 0.09
Isobutane 0.81 1.60 1.71
n-Butane 3.42 2.98 3.20
Isopentane 1.67 1.31 1.49
Pentane 0.38 0.19 0.29
2,2-Dimethylbutane 0.01 0.01 0.01
Cyclopentane 0.14 0.02 0.08
2,3-Dimethylbutane 0.05 ND 0.03
2-Methylpentane 0.10 0.08 0.09
3-Methylpentane 0.07 0.04 0.06
Hexane 0.04 0.01 0.03
Methylcyclopentane 0.04 0.04 0.04
2,4-Dimethylpentane 0.02 0.01 0.02
C4 Olefins 0.39 0.31 0.35
C5-C6 Olefins 1.00 0.65 0.83
Alcohols
Methanol 0.34 0.40 0.37
Ethanol NDC ND ND
Total Non-oxygenated HCd 8.5 7.8 8.2
Total Hydrocarbons 8.8 8.2 8.5
a<0.01, less than 0.005 g/test and greater than 0.001 g/test
bnone detected, for individual hydrocarbons, <0.001 g/test
cnone detected, for methanol and ethanol, <0.01 g/test
"Total FID hydrocarbons corrected for alcohol content
eSum of alcohols and non-oxygenated hydrocarbons
A-20
-------
APPENDIX B
HIGH TEMPERATURE EVAPORATIVE EMISSION RESULTS
-------
TABLE B-l. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-616-F
(WORK ASSIGNMENT 1Z)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
9.2
26
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCC
Total Hydrocarbonsd
Test 1
2.2
0.8
NDa
NRb
NR
8.1
8.1
Test 2
3.2
1.2
ND
NR
NR
8.0
8.0
Average
2.6
1.0
ND
NR
NR
8.1
8.1
aND - none detected, less than 0.02 g
"NR - not required
cTotal FID hydrocarbons corrected for alcohol content
"Sum of alcohols and non-oxygenated hydrocarbons
B-2
-------
TABLE B-2. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-642-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
4.75
4.75
8.5
31
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
1.1
0.2
2.7
NRa
0.8
15.9
19.4
Test 2
1.0
0.2
2.3
NR
0.9
14.0
17.2
Average
1.0
0.2
2.5
NR
0.9
15.0
18.3
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-3
-------
TABLE B-3. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-443-F
(WORK ASSIGNMENT 1Z)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
5.00
2.50
8.4
32
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCC
Total Hydrocarbonsd
Test 1
1.1
0.3
2.8
15.5
18.3
Test 2
0.8
0.2
3.7
NDa
NR
14.2
17.9
Average
1.0
0.3
3.3
<0.1
NR
14.9
18.1
aND - none detected, less than 0.02 g
^NR - not required
GTotal FID hydrocarbons corrected for alcohol content
of alcohols and non-oxygenated hydrocarbons
B-4
-------
TABLE B-4. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - LOW AROMATIC FUEL EM-644-F
(WORK ASSIGNMENT 1Z)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160<>F (D-86)
5.00
9.2
27
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
1.1
0.2
2.5
NRa
NR
13.3
15.8
Test 2
1.1
0.3
2.7
NR
NR
11.3
14.0
Average
1.1
0.3
2.6
NR
NR
12.3
14.9
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-5
-------
TABLE B-5. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-641-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
11.6
30
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HC"
Total Hydrocarbons0
Test 1
4.4
0.9
0.3
NRa
NR
15.1
15.4
Test 2
4.6
0.9
NR
NR
16.5
16.5
Average
4.5
0.9
0.2
NR
NR
15.8
16.0
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-6
-------
TABLE B-6. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-638-F
(WORK ASSIGNMENT 1Z)
Methanol, vol. %
Ethanol, vol. %
TBA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
4.75
4.75
11.6
37
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TBA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.4
0.8
3.6
NRa
1.6
16.8
22.0
Test 2
2.5
0.8
4.1
NR
0.9
17.3
22.3
Average
2.5
0.8
3.9
NR
1.3
17.1
22.2
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-7
-------
TABLE B-7. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-639-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
5.00
2.50
11.9
39
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.7
0.9
3.6
0.9
NRa
19.9
24.4
Test 2
2.5
0.8
4.2
0.4
NR
17.9
22.5
Average
2.6
0.8
3.9
0.6
NR
18.9
23.5
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-8
-------
TABLE B-8. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
HIGH RVP - LOW AROMATIC FUEL EM-640-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160<>F (D-86)
5.00
12.0
34
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
2.8
1.0
4.3
NRa
NR
16.1
20.4
Test 2
2.7
1.0
4.0
NR
NR
14.6
18.6
Average
2.8
1.0
4.2
NR
NR
15.4
19.5
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-9
-------
TABLE B-9. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-645-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
9.4
16
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCC
Total Hydrocarbons^
Test 1
2.4
0.4
NDa
NRb
NR
5.9
5.9
Test 2
2.4
0.4
ND
NR
NR
5.8
5.8
Average
2.4
0.4
ND
NR
NR
5.9
5.9
aND - none detected, less than 0.02 g
^NR - not required
cTotal FID hydrocarbons corrected for alcohol content
"Sum of alcohols and non-oxygenated hydrocarbons
B-10
-------
TABLE B-10. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-646-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
4.75
4.75
8.8
24
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbonsc
Test 1
1.5
0.5
1.3
NRa
0.3
9.4
11.0
Test 2
1.5
0.5
2.0
NR
0.4
10.4
12.8
Average
1.5
0.5
1.7
NR
0.3
9.9
11.9
aNR - not required
^Total FID hydrocarbons corrected for alcohol content
cSum of alcohols and non-oxygenated hydrocarbons
B-ll
-------
TABLE B-ll. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-647-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
5.00
2.50
9.1
28
Evaporative Results, e/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
1.6
0.5
2.5
0.2
10.3
13.0
Test 2
1.6
0.5
2.6
0.2
NR
12.6
15.4
Average
1.6
0.5
2.6
0.2
NR
11.5
14.2
aNR - not required
v *
"Total FID hydrocarbons corrected for alcohol content
GSum of alcohols and non-oxygenated hydrocarbons
B-12
-------
TABLE B-12. HIGH TEMPERATURE EVAPORATIVE EMISSIONS,
LOW RVP - HIGH AROMATIC FUEL EM-648-F
(WORK ASSIGNMENT 12)
Methanol, vol. %
Ethanol, vol. %
TEA, vol. %
RVP, psi
Percent Fuel Distilled at 160°F (D-86)
5.00
9.6
24
Evaporative Results, g/test
Butane
Isobutane
Methanol
Ethanol
TEA
Total Non-oxygenated HCb
Total Hydrocarbons0
Test 1
1.4
0.5
1.8
NR*
NR
9.3
11.1
Test 2
1.3
0.5
2.3
NR
NR
10.2
12.5
Average
1.4
0.5
2.1
NR
NR
9.8
11.8
aNR - not required
"Total FID hydrocarbons corrected for alcohol content
GSum of alcohols and non-oxygenated hydrocarbons
B-13
-------
TECHNICAL REPORT DATA
(Please read Instruction! on the reverse before completing)
1. REPORT NO.
460/3-87-001
3. RECIPIENT'S ACCESSION>NO.
4. TITLE AND SUBTITLE
VAPOR GENERATION OF FUELS
5. REPORT DATE
August 1987
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Lawrence R. Smith
8. PERFORMING ORGANIZATION REPORT NO,
Work Assignment B-7
9. PERFORMING ORG "VNIZATION NAME AND ADDRESS
Southwest Research Institute
6220 Culebra Road
San Antonio, Texas 78284
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-03-3353
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Protection Agency
2565 Plymouth Road
Ann Arbor, MI 48105
13. TYPE OF REPORT AND PERIOD COVERED
Final(4-9-8776-87)
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This report combines the data from two previous work assignments (Work Assignments
12 and 18 of Contract 68-03-3192) conducted at Southwest Research Institute for
the Environmental Protection Agency, and analyzes the resulting data set. When
possible, the combined results have been generalized in order to draw conclusions.
In Work Assignment 12, vapors from twelve gasolines and gasoline/alcohol blends
were analyzed for butanes, total hydrocarbons, methanol, and appropriate cosolvent
alcohols. The analyses were conducted in duplicate for each fuel at FTP diurnal
SHED temperatures (60-84°F) and at typical hot soak temperatures (160±10°F). The
fuels were prepared with different levels of aromatic content and Reid Vapor
Pressure. The Work Assignment 18 study involved generating vapors from seven
gasolines and gasoline/alcohol blends during simulated diurnal test conditions
(15-40°F, 35-60°F, and 60-84°F). These vapors were analyzed for total hydrocarbons,
aJcohols, and individual hydrocarbons up to and including Cg. The Reid Vapor
Pressure of the seven fuels varied from 9.2 to 15.0 psi.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI I-ield/Group
Air Pollution
Evaporative Emissions
Gasoline/alcohol blends
Fuel Effects
FTP SHED Tests
Temperature Effects
18. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
76
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
------- |