72-4
Emissions From the Methanol Fueled
Stanford University Gremlim
August 1971
H. Anthony Ashby
Office of Air Programs
ENVIRONMENTAL PROTECTION AGENCY
-------
Background
The methanol-fueled AMC Gremlin built by Stanford University
students was named winner in the Liquid Fuel Division of the
1)970 Clean Air Car Race. For this reason the car was evaluated
by the Test and Evaluation Branch, as a prototype vehicle under
the Federal Clean Car Incentive Program, between March 1 and
March 19, 1971.
Control Technique
The use of methanol as a fuel is the basic technique used in
the Stanford Gremlin for control of pollutant emissions.
Carburetor jets were changed to furnish air-fuel ratios slightly
on the lean side of stoichiometric. The intake manifold was
modified to supply additional heat to the mixture. An Engelhard
catalyst was placed about six inches downstream of the exhaust
manifold. An exhaust gas recirculation system was installed, but
not used during the course of our tests.
TestProgram
The test car was an American Motors Gremlin with a 232 cubic-
inch six-cylinder engine and standard three-speed transmission.
Methanol fuel was obtained from a local chemical supply company.
$
Test procedures included the 1972 Federal Test Procedure (per
the November 10, 1970, Federal Register), the 1970 FTP, and the
9x7 procedure, all with hot starts as well as cold starts.
At the start of the program lead-free gasoline was used as the
fuel for one 1972 FTP and one 9x7 test, to provide baseline
emission data.
After testing at Ypsilanti was completed, the car was delivered
to the Division of Chemistry and Physics, Fairfax Facility,
Cincinnati, Ohio, for a thorough characterization of hydrocarbons
and determination of aldehyde emissions.
Results
Results of the emissions tests are presented in Tables 1 and 2.
Table 1 is from the 1972 FTP, while 7-mode cycle results are in
Table 2. In the 1972 FTP and the 9x7 procedures, HC data are
determined by FID, and NOX emissions by two techniques:
chemiluminescence (C.L.) and Saltzman. In the 1970 FTP all data
are determined by NDIR. All NOX emissions data presented in
Tables 1 and 2 are reported as N02, corrected to 75 grains
humidity.
-------
The 1972 FTP mass emissions data show good control of emissions,
as the car comes very close to meeting the 1975-76 Federal
standards of .41 gm/mi HC, 3.4 gm/mi CO, and .4 gin/mi NO .
A.
Results from the testing at DCP Cincinnati are summarized in
this report as Appendix A. Appreciation is extended to John
Sigsby for these data.
Conclusion
The results of these tests indicate that the use of methyl
alcohol as fuel can result in very low emissions. The most
noticeable change on this car was in the reduction of NOx when
changing from gasoline to methanol. This may be due chiefly to
the higher heat of vaporization of methanol, leading to a lower
flame temperature.
-------
Table 1
Stanford Methanol Gremlin
Mass Emissions
1972 Federal Test Procedure
fcst No.
2-
2-
2-
2-
2-
2-
;; -
.:-
-*_
2-
2-
1350
1361
1368
1376
1378
1408
1353
1370
1377
1409
1331
HC
gm/mi
.33
.50
.58
.43
.64
.24
.09
.06
.04
.04
.34
CO
gm/mi
1.30
13.13
4.57
5.77
12.61
3.55
.20
.92
.50
.49
5.44
NOX
C.L.
gm/mi
.20
no data
.22
no data
.22
.30
.17
.20
.09
.26
4.74
NOX
Saltzman
gm/mi
.31
.29
.24
5.23*
.25
.30
.37
.23
2.22*
.27
4.27
Comments
Standard
Standard
Standard
Standard
*>
Standard
Standard
Hot Start
Hot Start
Hot Start
Hot Start
Test
Test
Test
Test
Test
Test
Cold, Gasoline
Saltzman data believed not correct.
-------
Table 2
Stanford Methanol Gremlin
Mass Emissions
7-Mode.Driving Cycle
e s t No .
2-1391
2-1400
2-1367
2-1401
::-1333
0618
-0622
-0615
-0623
HC
gm/mi
.32
1.58
.05
.10
.28
.32
.47
.19
.20
CO
gm/mi
3.87
9.46
1.37
.23
7.25
1.59
2.17
.34
.16
NOX
C.L.
gm/mi
.39
.20
.04
.55
2.80
.09 by NDIR
.as by NDIR
no data
.10 by NDIR
NOX
Saltzman
gm/mi
.32
.36
.41
.46
2.41
Comments
9x7
9x7
9x7 Hot
9x7 Hot
9x7 Cold,
Gasoline
70 FTP
70 FTP
70 FTP Hot
70 FTP Hot
-------
Appendix A
1. Tests were performed using the proposed 1972-3 Federal
cycle from both a cold and a hot start. A 3500 Ib. fly-
wheel was used. The hot start consisted of insuring that
the car was thoroughly warmed up; turning it off, and within
ten minutes re -running the Federal cycle. The cold starts
were run after an overnight soak on the dynamometer. After
these runs were made, the catalyst was9 removed and one run
each was made from both a cold and a hot start. One false
start, i.e., the engine died at the beginning of the cycle,
occurred on each of the cold starts except C7. The vehicle
was restarted and the test begun over. The effluent was
defined by the constant volume sampler. The summary of
these results is shown in the attached tables.
2. As expected, few aldehydes other than formaldehyde, were
present in appreciable quantities. DNPH derivatives were
made and gas chromato graphed to determine the distribution
of the aldehydes formed. This confirmed the wet chemical
tests which are shown in the tables. Formaldehyde was the
only specific aldehyde that could be quantitatively measured,
traces of higher aldehydes were also seen with acetaldehyde
being the most abundant.
3. A remarkable number of other hydrocarbons were seen over
background. Concurrent background samples were collected
and analyzed for each run. The values are confirmed by the
runs which were made with the catalyst removed. As might
be expected, the primary hydrocarbons produced were olefinic
in nature. Any reactivity consideration must be based on the
reactivity of methanol which overrides any other compound in
concentration.
4. The largest effect of the catalyst was to reduce the methanol
90% for cold starts and 96% for hot. The catalyst also re-
duced CO by about 701 while having no effect on the oxides
of nitrogen. Aldehydes were reduced 75 to 80%.
5. Methane was not measureable above background in the hot
start tests. It was very low in the cold starts accounting
for 4% of the total. Methanol accounted for 95% and 97% of the
hydrocarbons seen from cold and hot starts respectively.
6. The largest difference between cold and hot starts were in
hydrocarbons and CO which decreased between 80 and 90%.
Aldehydes were only reduced 30% and C0£ and NOX about 10%.
7. The NOX emissions were predominately NO with little NOx or
reduced nitrogen present.
-------
Appendix A
Stanford Methanol Gremlin
With Catalyst
Cold Start Tests
Run #
Compound
Methanol
Methane
Ethylene
Butene-1/2
Methyl Propene
Propylene
Ethane
Isobutane
Acetylene
N-Pentane
TOTAL
C4
ppmc
137
5.6
0.47
0.44
-
0.31
0.31
.
144
C5
ppmc
220
9.1
1.0
0.62
2.2
0.44
trace
0.08
233
C7
ppmc
127
5.2
0.47
0.01
0.71
0.37
0.07
134
Average
161
6.6
0.6
0.4
170
Mass Emissions
Hydrocarbon
CO
C02
NOX
Total
Aldehydes
Formaldehyde
0.17
2.88
545
0.54
0.077
0.075
0.22
3.51
541
0.57
0.099
0.089
grams/mile
0.14
3.35
548
0.54
0.093
0.086
0.18
3.3
545
0.55
0
0.090
0.083
-------
Appendix A
Stanford Methanol Gremlin
With Catalyst
Hot Start Tests
Run # 03
Compound ppmc
Methanol 27
Methane
Ethylene 0.47
Butene-1/2 methyl 0.03
Propene
Isobutane
N-Pentane
Iso pentane
Propylene
Ethane
TOTAL 27. S
Hydrocarbon 0.02
CO 0.61
C02 490
NOX 0.506
Total Aldehyde 0.033
Formaldehyde 0.019
C$ GS Average
ppmc ppmc
26 33 29
0.18 0.47 0.37
1.0 .06
0.'76
1.0
0.01
trace
28.8 33.6 30
Mass Emissions
grams /mile
0.02 Not Measured 0.02
0.46 0.75 0.61
506 486 494
0.48 0.45 0.48
a. 076 0.085 0.065
0.072 0,079 0.057
-------
Appendix A
Stanford Methanol Gremlin
Catalyst Removed
Run #
Compound
Methanol
Methane
Ethylene
Butene-1/2 Methyl
Propene
Propylene
f.thane
] sobutane
Acetylene
N-Pentane
TOTAL HYDROCARBON
Hydrocarbon
CO
C02
NOX
Total Aldehyde
Formaldehyde
COLD START
C9
ppmc
1580.
7.8
4.2
0.49
trace
trace
0.09
1.72
0.10
1600
Mass Emissions
grams /mile
1.33
10.8
520
0.45
0.36
0.34
HOT START
C10
ppmc
810
Not measured
5.0
0.28
0.21
trace
0.40
1.16
0.03
820
0.77
2.6
488
0.43
0.33
0.30
------- |