72-iJ
Emissions Prom the Methanol Fueled
Stanford University Gremlim
August 1971
H. Anthony Ashby
Office of Air Programs
ENVIRONMENTAL PROTECTION AGENCY
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Background
The metHanoi-fueled AMC Gremlin built by Stanford University
students was named winner in the Liquid Fuel Division of the
1970 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 ad'dTtional 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.
Test Program
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 arid 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 NO^ emissions data presented in
Tables 1 and 2 are reported as N02, corrected to 75 grains
humidity.
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1__-
,
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 gm/mi NOx.
Re'sul ts 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 maybe due chiefly to
the higher heat of vaporization of methanol, leading to a lower
flame temperature.
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Tab Ie I
Stanford Methanol Gremlin
Mass Emissions
1972 Federal Test Procedure
Test No. HC CO NOx NOx Comments
gm/mi gm/mi C.L. Saltzman
gm/mi gm/mi
"12-1350 .33 1.30 .20 .31 Standard Test
12-1361 .50 13.13 no data .29 Standard Test
12-1368 .58 4.57 .22 .24 Standard Test
12-1376 " .43 5.77 no data 5.23* Standard Test
12-1378 .64 12.61 .22 .25 Standard Test
"12-1408 .24 3.55 .30 .30 Standard Test
--1353 .09 .20 .17 .37 Hot Start
12-1370 .06 .92 .20 .23 Hot Start
12-1377 .04 .50 .09 2.22* Hot Start
12-1409 .04 .49 .26 .27 Hot Start
12-1331
.34
5.44
4. 74
4.27
Cold, Gasoline
* Saltzman data believed not correct.
_.=:--'''''''-~''--''''-~''------~-~---'--.-._, '--
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Table 2
Stanford Methanol Gremlin
Mass Emissions
7 - Mo de Driving Cycle
Test No. HC CO NOx NOx Comments
gm/mi gm/mi C.L. Sa1 tzman
gm/mi gm/mi
12-1391 .32 3.87 .39 .32 9 x 7
12-1400 1. 58 9.46 .20 .36 9 x 7
12 -136 7
12-1401
.05
.10
1.37
.23
12-1333
.28
7.25
6-0618
6-0622
.32
1. 59
2.17
.47
6-0615
6-0623
.19
.34
.20
.16
.04
.55
.41
.46
9 x 7 Hot
9 x 7 Hot
2.80
2.41
9 x 7 Cold,
Gasoline
.09 by NDIR
.15 by NDXR
70 FTP
70 FTP
. no data
70 FTP Hot
.10 by NDIR
70 FTP Hot
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1.
Appendix A
Tests were performed using the proposed 1972-3 Federal
cycle from both a cold ahd a hot start. A 3500 lb. 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 was removed and one run
each was made from both a cold and a hot start. One false
sta~t, 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 arid gas chromatographed 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 70% while having no effect on the oxides
of nitrogen. Aldehydes were reduced 75 to 80%.
Methane ,...as not measureable above background in the hot
start tests. It was very low in the cold starts accounting
for 4% of the total. Nethanol accounted for 95% and 97% of the
hydrocarbons. seen from cold and hot starts respectively.
5.
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 C02 and NOx about 10%.
The NOx emissions were predominately NO with little NOx or
reduced nitrogen present.
7.
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~ '
Appendix A
Stanford Methanol Gremlin
With Catalyst
Cold Start Tests
Run # C4 C5 C7 Average
Compound ppmc ppmc ppmc
Methanol 137 220 127 161
l>lethane 5.6 9.1 5.2 6.6
Ethylene 0.47 1.0 0.47 0.6
Butene-1/2 0.44 0.62 0.01 0.4
Methyl Propene
Propylene 2.2 0.71
Ethane 0.31 .0.44
obutane 0.31 trace 0.37
Acetylene 0.08
N-Pentane 0.07
TOTAL 144 233 134 170
Mass Emissions
grams/mile
Hydrocarbon 0.17 0.22 0.14 0.18
CO 2.88 3.51 3.35 3.3
C02 545 541 548 545
NOx 0.54 0.57 0.54 0.55
Total
Aldehydes 0.077 0.099 0.093' 0.090
rmaldehyde 0.075 0.089 0.086 0.083
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Appendix A
Stanford Methariol Gremlin
I With Catalyst
Hot Start Tests
-
I Run # C3 C6 C8 Avera,ge
Compound ppmc ppmc ppmc
Methanol 27 26 33 29
~Iethane
Ethylene 0.47 0.18 0.47- 0.37
.'
Butene-l/2 methyl 0.03
Propene
Isobutane 1.0 -.06
N-Pentane 0: 76 !
-i
T~o pentane 1.0 :
J. J.'opyl.ene ., 0.01
Ethane trace
TOTAL 27.5 28.8 33.6 30
Mass Emissions
grams/mile
Hydrocarbon 0.02 0.02 Not Measured 0.02
CO 0.61 0.46 0.75 0.61
C02 490 506 486 494
NOx - 0.506 0.48 0.45 0.48
Total Aldehyde 0.033 0-.076 0.085 0.065
Formaldehyde 0.019 0.072 0.079 0.057
. - - - -~. -- <-
--~.._~ - -"..... -...,.-, ,--,------,- .
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Appendix A
Stanford Methanol Gremlin
Catalyst Removed -
Run #
COLD START
C9
. HOT START
C10
Compound
. ~lethano1
ppmc
ppmc
~lethane
1580.
7.8
810
Not measured
Ethylene
Butene-1/2 Methyl
Propene
4.2
5.0
.obutane
0.49
trace
!
trace .,
0.09
1. 72
0.10
1600
0.28
0.21
Propylene
Ethane
trace
0.40
Acetylene
1.16
0.03
N-Pentane
TOTAL HYDROCARBON
820
Mass Emissions
grams/mile
Hydrocarbon 1.33 0.77
CO 10.8 2.6
C02 520 488
NOx 0.45 0.43
Total Aldehyde 0.36 0.33
Formaldehyde 0.34 0.30
..,. ....0 --7-
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