76-18 EAB Sulfuric Acid Emissions from a Union Carbide Low Sulfate Catalyst April 1976 Technology Assessment and Evaluation Branch Emission Control Technology Division Office of Mobile Source Air Pollution Control Environmental Protection Agency ------- Background To meet the emission levels required by the Clean Air Act, most vehicle manufacturers use oxidation catalysts as part of their vehicle's emission control system. By using a catalyst, the manufacturers have been able to calibrate their vehicles to achieve good fuel economy even while they have had to meet more stringent emission standards (1) . However, during tests in recent years, it was observed that small amounts of exhaust SO- were converted to sulfuric acid mist by oxidation catalysts (2,3). Because of the possible adverse health effects, EPA has undertaken efforts to develop sampling systems and teat procedures (4) and to evaluate the sulfate emissions characteristics of various systems. ' Laboratory tests of a metal oxidation catalyst by Union Carbide (UC) has shown promise for low sulfate emissions in a vehicle. In bench checks a large portion of the SO. injected had formed elemental sulfur after passing through the catalyst. Union Carbide offered several units to EPA for vehicle testing. ECTD, because of its interest in evaluating technology which could have an impact on sulfate emissions, agreed to test the catalysts. The Environmental Protection Agency receives information about many systems which appear to offer potential for emissions reduction or improvement in fuel economy compared to conventional engines and vehicles. EPA's Emission Control Technology Division is interested in evaluating all such systems, because of the obvious^benefits to the Nation from the identification of systems that can reduce emissions, improve economy, or both. EPA invites developers of such systems to provide to the EPA complete technical data on the system's principle of operation, together with available test data on the system. In those cases in which review by EPA technical staff suggests that the data available show promise for the system, attempts are made to schedule tests at the EPA Emissions ^Laboratory at Ann Arbor, Michigan. The results of all such tests are set forth in a series of Technology Assessment and Evaluation Reports, of which this report is one. The conclusions drawn from the EPA evaluation tests are of limited applicability. A complete evaluation of the effectiveness of an emission control system in achieving improvements on the different types of vehicles that are in actual use requires a much larger sample of test vehicles than is economically feasible in the evaluation test projects conducted by EPA. For promising systems it is necessary that more extensive test programs be carried out. Numbers in parenthesis designate reference listed at end of this report. ------- The conclusions from this EPA evaluation test can be considered to be quantitatively valid only for the specific test car used. However, it is reasonable to extrapolate the results from the EPA test to other types of vehicles in a directional or qualitative manner, i.e., to' suggest that similar results are likely to be achieved on other types of vehicles. System Description The Union Carbide unit is a monolith metal oxidation catalyst. The active material is a non-noble metal ceramic material that is supported by a corrugated wire mesh (See Figure 1). A strip of the mesh and ceramic is rolled up lengthwise to form a cylindrical biscuit. Since complete characteristics of the UC catalyst were unknown, a test vehicle was selected whose original equipment catalyst approximated the known general characteristics (space velocity, size, monolith) of the UC catalyst. Also, since studies had shown that catalyst vehicles with excess air have higher sulfate emissions (5), the test vehicle would have an air pump to provide a severe test of the UC catalyst's effectiveness. A survey was conducted for a suitable vehicle. Included in the survey were cars made by Chrysler, Datsun, Ford, and Volkswagen. The 1975 Ford Pinto 2.3 litre, 49 State, catalyst vehicle was chosen as most compatible. Walker Manufacturing (a manufacturer of automotive mufflers and catalyst cans) volunteered their research facilities to fabricate a suitable container. They canned the biscuit in a package identical to the original. (The test vehicle is described in detail on page 4.) Test Procedures Exhaust emissions tests were conducted according to the 1975 Federal Test Procedure ('75 FTP), described in the Federal Register of November 15, 1972 except thatIno evaporative emissions tests were conducted. ^Additional tests included the EPA Highway Fuel Economy Test (HFET), described in the Federal Register, Volume 39, Number 200, October 15, 1974, the sulfate cycle, and steady state emissions tests. All tests were conducted using an inertia weight of 3000 pounds (1360 kg) with a road load setting of 10.3 horsepower (7.7 kW) at 50 miles per hour (80.5 km/hr). The sulfate procedure employed a test series consisting of a 75 FTP, an EPA Highway cycle, and several sulfate cycles (see attachment). All testing was done using a fuel doped to a level of .03 percent sulfur with di-tertiary butyl disulfide. The vehicle was preconditioned by driving either 500 miles (monolith catalyst) or 1000 miles (pelleted catalyst) of the AMA durability cycle while using the sulfurized fuel. To permit the catalyst to age, the UC catalyst was driven 2000 miles before sulfate testing was initiated. The vehicle was tested in three configurations: no catalyst, factory catalyst, and UC catalyst. All three units were similar (See Figure 2). ------- Exhaust Gas Flow Catalyst and supporting wire mesh Figure 1 Union Carbide Catalyst Biscuit Factory Catalyst Union Carbide Catalyst Union Carbide Catalyst Figure 2A Catalysts Figure 2B Catalyst Installation ------- TEST VEHICLE DESCRIPTION Chassis model year/make - 1976 Ford Pinto Emission control system - Catalyst Engine type 4 stroke, Otto cycle, inline 4 cylinder bore x stroke 3.78 x 3.13 in./96.0 x 79.5 mm displacement 140 cu. in./2300 cc compression ratio 9.0:1 maximum power @ rpm 88 hp/65.6 kW fuel metering single 2 barrel carburetor fuel requirement regular unleaded, tested with 96 RON Indolene HO unleaded with .03% sulfur Drive Train 0>Y weight) transmission type 3 speed automatic final drive ratio . 3.18:1 Chassis type unitized body/frame, front engine, rear drive tire size A 78 x 13 curb weight inertia weight 3000 pounds passenger capacity 4 Emission Control System basic type ............ alr injection EGR factory catalyst monolith 3.64 in. diameter x 6 in. long effective volume 52 cu. in. Corning-substrate Engelhard-catalyst Walker-container Union carbide catalyst monolith 4 in diameter x 3 in. long effective volume 37 cu. in. UC substrate UC catalyst Durability accumulated on system . 3480 miles with factory catalyst 2200 miles with UC catalyst ------- An empty catalyst can was used to permit baseline vehicle emissions to be established. These values were then used to evaluate the efficiency of the two catalysts. The UC catalyst was equipped with temperature probes (See Figure 2), to allow test personnel to determine if and when catalyst lightoff occurred. Test Results The Union Carbide catalyst performed well. As a catalyst it achieved smaller reductions in HC and CO emissions than the factory catalyst (see summary results below), but the vehicle easily met the 1976 emission standards. The sulfate emissions were repeatable, stable, and unexpec- tedly low (see summary results below) particularly for a vehicle using an air pump. The detailed results are tabulated in Tables 1 through 4. Emissions tests were conducted at low mileage to verify the satis- factory operation of the UC catalyst. This also permitted the catalyst deterioration to be observed. The results for the"75 FTP and HFET are tabulated below: Low Mileage '75 FTP Composite Mass Emissions grams per mile ; (grains per kilometre) System Mileage (kilometres) HC CO C0 NOx Baseline 2870 (2 test) (4623) Factory Catalyst 27l3 x(l test) (4366) UC Catalyst 328 (2 test) (527) Factory Catalyst % Change from Baseline UC Catalyst % Change from Baseline 1.33 21.52 365 2.04 (.83) (13.37) (227) (1.26) .37 2.46 420 2.11 (.23) (1.53) (261) (1.31) .67 5.54 396 1.71 (.42) (3.44) (246) (1.06) -72% -89% 15% -3% -50% -74% 8% -16% Fuel Economy (Fuel Consumption) 22.0 miles/gal (10.7 litres/100 km) 20.9 miles/gal (11.3 litres/100 km) 21.8 miles/gal (10.8 litres/100 km) -5% -1% On the EPA Highway Cycle the results were: ------- Mass Emissions Low Mileage EPA Highway Fuel Economy Test grams per mile (grams per kilometre) System Mileage (kilometres) HC CO CO, NOx Fuel Economy (Fuel Consumption) 2894 (4657) 2734 (4400) 344 (554) .e .78 (.48) .16 (.10) .40 (.25) -79% -49% 2.31 (1.44) .16 (.10) 1.03 (.64) -93% -55% — t 267 (166) 299 (186) 287 (178) 12% 7% 2,47 (1.53) 2.76 (1.72) 2.90 (1.80 12% 17% 32.5 miles/gal (7.4 litres/100 km) 29.6 miles/gal 8.0 litres/100 km) 30.6 miles/gal (7.7 litres/100 km) -9% -6% Baseline (2 tests) Factory Catalyst (1 test) UC Catalyst (1 test) Factory Catalyst % Change from Baseline UC Catalyst % Change from Baseline Thus, the UC catalyst achieved significant reductions in HC and CO emissions, at low mileage. However, as an oxidation catalyst it was not as efficient as the factory unit. The vehicle then underwent mileage accumulation to age the UC catalyst. The factory catalyst later underwent mileage accumulation to precondition the factory unit prior to sulfate tests. The results of the sulfate tests were: '75 FTP Composite Mass Emissions grams per mile (grams per kilometre) System Mileage (kilometres) HC CO CO, NOx Baseline Factory Catalyst U.C. Catalyst 5202 (8372) 3386 (5449) 2088 (3360) 1.49 14.74 383 2.02 (.93) (9.16) (238) (1.26) .35 2.70 386 1.90 (.21) (1.68) (240) (1.18) .82 4.80 375 1.98 (.51) (2.98) (234) (1.23) 1975-76 Federal Standards Factory Catalyst % Change frcm Baseline UC Catalyst % Change from Baseline 1.5 15.0 -77% -82% 1% -45% -67% -2% 3.1 -6% -2% Fuel Economy (Fuel Consumption) 21.6 miles/gal (10.9 litres/100 km) 22.7 miles/gal (10.4 litres/100 km) 22.8 miles/gal (10.3 litres/100 km) 5% ------- The corresponding EPA Highway Fuel Economy Test results were: EPA Highway Fuel Economy Test Mass Emissions grams per mile (grams per kilometre) Baseline Factory Catalyst UC Catalyst Factory Catalyst % Change from Baseline UC Catalyst % Change from Baseline System Mileage (kilometres) 5224 (8406) 3425 (5512) i 2126 (3432) HC CO c NOx .90 2.10 298 2.22 ;.56) (1.30) (185) (1.38) .17 18 303 2.48 Ml) (.11) (188) (1.54) .45 .85 292 2.59 ;.28) (.53) (181) (1.61) -82% -91% +2% 12% -50% -60% -2% 17% Fuel Economy (Fuel Consumption) 29.1 miles/gal (8.1 litres/100 km) 29.3 miles/gal (8.0 litres/100 km) 30.1 miles/gal (7.8 litres/100 km) 1% 3% In these tests after 5000 durability miles the UC catalyst again achieved significant reductions in HC and CO emissions, although it was not as efficient as the factory unit. The percent change in HC and CO emission reductions remained constant for each catalyst. Thus, on the basis of this limited data, the UC catalyst has no readily apparent deterioration problem. The sulfate results for the above tests are listed in Tables 2 and 3. They are not noted above because the sulfate emissions over the '75 FTP and the EPA Highway Cycle are not representative of a vehicle's sulfate emissions over the sulfate emission te;st. cycle:. The principle thrust of this report, the vehicle's sulfate emissions over the sulfate cycle, are summarized below and tabulated in Table 4: Sulfate Cycle Sulfate Emissions System Mileage Factory Catalyst 3423 (5508) UC Catalyst 2116 (3405) H-SU, mgm/mile Z cf - 27.5 (range 20.6-39.4) 6.1 (range 3.2-8.2) For comparison,' typical vehicle sulfate emission results (5) as found in the EPA sulfate baseline study were: Vehicles calibrated to meet present, and future emission standards. ------- System Mileage H0SO, m^m/mile £. H- Catalyst vehicles with excess air 30 (range 0.3-96) Catalyst vehicles without excess air 17 (range 0.5-83) 3-way catalyst vehicles 1 Non-catalyst vehicles 1 The UC catalyst sulfate emissions were stable and low, particularly for a vehicle using an air pump. Steady State fuel economy results in miles per gallon, were: Speed, mph Baseline Factory Catalyst UC Catalyst 15 30 45 60 24.2 32.9 33.3 29.6 26.5 32.9 33.1 28.4 27.2 32.8 33.1 28.6 Thus there was no significant steady state fuel economy difference among the three configurations. A comparison of the test vehicle's combined city/highwgy fuel economy, with that of the 1976 certification Pinto (as published in the 1976 EPA Buyer's Guide), showed no fuel economy penalty. When compared to all vehicles in the same inertia weight class (3000 Ibs) the test vehicle and the certification vehicle had an 8% fuel economy improvement. City/Highway Combined Fuel Economy (Fuel Consumption) Vehicle miles/gal litres/100 km Test Pinto, Baseline 24.5 (9.6) Test Pinto, Factory Catalyst 25.3 (9.3) Test Pinto, U.C. Catalyst ' 25.6 (9.2) Ford Certification Vehicle 25.7 (9.1) (140 CID) Average of all 3000 Ib Vehicles 23.6 (10.0) (avg. 150 CID) ------- In calculating city/highway combined fuel economy, the urban fuel economy is weighted 55% and the highway fuel economy is weighted 45% to account for the 55/45 ratio of urban to rural mileage accumulation. MPG , . . combined .55 + .45 urban nighway The vehicle had good driveability. Conclusions The Union Carbide catalyst performed well. As an oxidation catalyst it achieved smaller reductions in HC and CO emissions than the factory catalyst. The sulfate emissions were repeatable, stable, and unexpectedly low, particularly for a vehicle using an air pump. However an increase in catalyst size to achieve comparable emission reductions might change sulfate emissions. ------- 10 References 1. T. C. Austin, R. B. Michael, and G. R. Service, "Passenger Car Fuel Economy Trends through 1976", SAE paper 750957, presented at Automobile Engineering Meeting, Detroit, Michigan, October 1975. 2. W. R. Pierson, R. H. Hammerle, J. T. Kummer, "Sulfuric Acid Aerosol Emissions from Catalyst-Equipped Engines." SAE Publication Number 740287, Detroit, Michigan, February 1974. 3. R. L. Bradow, John B. Moran, "Sulfate Emissions from Catalyst Cars, A Review," SAE Publication Number 750090, Detroit, Michigan, February 1975. 4. J. H. Somers, R. Lawrence, C. E. Fett, T. M. Baines, and R. J. Garbe, "Sulfuric Acid Emission from Light Duty Vehicles," SAE paper 760034, presented at the Automotive Engineering Congress and Exposition, Detroit, Michigan, February 1976. 5. Internal report "Test Report, Automotive Sulfuric Acid Baseline Program," EPA, Emission Control Technology Division, January 1976. ------- 11 Attachment Ford Pinto Procedures used to measure Sulfate Emissions 1. The fuel was drained from the test vehicle. The vehicle was refueled with Indolene HO gasoline containing .020% sulfur by weight. 2. The catalyst was stabilized by driving 500 miles of the AMA durability cycle to stabilize the sulfate loading of the catalyst. 3. The following sequence of test cycles was used to measure sulfate emissions. a) 75 FTP b) Sulfate emission test c) Sulfate emission test d) EPA Highway driving cycle e) Sulfate emission test f) Sulfate emission test. ------- Table 1A Baseline '75 FTP Mass Emissions grains per mile Bag 1 Cold Transient Bag 2 .Hot Stabilized Bag 3 Hot Transient Fuel . Fuel Fuel Vehicle System . Economy Economy Economy Test Number Mileage Mileage ' HC CO C02 NOx MPG HC CO CO^ NOx MPG HC CO C02 NOx MPG 76-3118 2852 2852 1.95 33.76 375 2.70 20.5 1.24 24.98 373 1.38 21.3 1.18 12.78 351 2.68 23.7 76-3125 2893 2893 1.71 28.60 373 2.71 21.0 1.20 21.29 365 1.43 22.1 1.15 9.49 351 2.79 24.0 77-129 5197 5197 1.84 26.92 404 2.67 19.6 1.38 14.25 390 1.59 21.3 1.41 6.77 361 2.52 23.6 ^ 77-149 5208 5208 1.91 28.38 405 2.58 19.5 1.34 13.18 385 1.51 21.6 1.50 7.12 355 2.40 23.9 ------- Table IB Factory Catalyst '75 FTP Mass Emissions grams per mile Vehicle System Test Number Mileage Mileage 76-3099 * 77-212 77-247* 2713 5799 5875 2713. 3348 3424 Bag 1 Cold Transient ...- Fuel Economy HC_ CO CQ2 , NOx MPG HC .90 10.64 434 2.70 19.5 .20 .85 14.5.4 425 2.53 19.7 .20 .70 8.62 443 2.62 19.4 .19 Bag 2 Hot Stabilized CO C02 .21 420 .20 382 .24 389 Bag 3 Hot Transient NOx .51 ..41. ..37 Fuel Economy MPG 20.6 23.2 22.8 HC .31 .30 .32 CO .58 .73 .78 CO? 390 358 342 NOx 2.81 2.34 2.39 Fuel Economy MPG 22.6 24.7 25.8 * Sulfate emissions taken. ------- Table 1C Union Carbide '75 FTP Mass Emissions grams per mile Bag 1 Cold Transient Bag 2 Hot Stabilized Bag 3 Hot Transient Fuel " Fuel Fuel Vehicle System Economy Economy Economy Test Number Mileage Mileage HC CO C02 . NOx MPG HC_ CO C02 NOx MPG HC CO C02 NOX MPG 76-3321 3245 321 1.26 lc.07 430 1.12 19.4 .51 • 3.56 421 1,44 20.7 .57 3.00 370 1.10 23.5 76-3313 3258 334 1.10 12.40 412 2.95 20.4 .53 3.68 385 1.49 22.6 .56 3.03 352 2.74 24.8 76-3518* 4934 2010 1.23 12.79 418 20.1 .87 .80 397 2.82 22.1 1.08 2.69 375 1.79 23.2 76-3534*. 5009 2085 1.06 14.36 400 2.49 20.8 .60 3.29 364 1.33 23.9 .73 3.54 342 2.24 25.4 76-3577* 5093 2169 1.03 13.07 387 2.70 21.6 .60 3.11 364 1.64 23.9 .71 2.42 346 2.65 25.2 * Sulfate emissions taken. ------- 15 Table 2A Baseline '75 FTP Composite Mass Emissions grams per mile Test Number 76-3118 76-3125 77-129 77-149 Test Vehicle N.umber Mileage 76-3099 2713 t 77-212 5799 77-247 5875 Vehicle Mileage 2852 2893 5197 5208 Factory System Mileage 2713 3348 3424 System Mileage 2852 2893 5197 5208 HC CO 1.37 23.46 1.29 19.57 1.48 14.82 1.50 14.66 Table 2B Catalyst '75 FTP Composite grams per mile HC CO .37 2.46 .36 3.29 .33 2.11 C02 NOx 420 2.11 384 1.90 387 1.90 Fuel Economy CO 2 NOx MPG 367 2.01 21.7 363 2.06 22.3 385 2.07 21.5 381 1.97 21.7 Mass Emissions Fuel Economy MPG H7S04 % Conversion 20.9 22.7 19.7 15 22.7 9.7 7.3 mgm per mile H^SO, , values normalized to .030% sulfurized fuel. ------- 16 Table 2C Union Carbide Catalyst '75 FTP Composite Mass Emissions grams per mile Test Number 76-3321 76-3313 76-3518 76-3544 76-3577 Vehicle Mileage 3245 3258 4934 5009 5093 System Mileage HC 321 334 2010 2085 2169 .68 .66 1.00 .73 .72 CO 5. 5. 3. 5. 4. 78 30 79 64 97 C02 409 382 395 365 364 NOx 1. 2. 1. 2. 28 13 82 13 Fuel Economy MPG Ho SO,. 21. 22. 22. 22. 23. 1 6 0 2.4 6 2.1 7 .71 % Conversion 1.9 1.7 .6 mgm per mile H-SO^, values normalized to .030% sulfurized fuel. ------- 17 Table 3A Baseline Highway Cycle Mass Emission grams per mile Test Number 76-3118 76-3125 77-129 77-149 Vehicle Mileage 2873 2915 5206 5241 System Mileage 2873 2915 5206 5241 HC .79 .76 ..90 .90 CO 2.98 1.64 2.15 2.04 CO? 266 268 305 291 NOx 2.49 2.45 2.34 2.09 Fuel Economy MPG 32.5 32.5 28.5 29.8 Table 3B Factory Catalyst Highway Cycle Mass Emissions grams per mile Test Number \ 76-3099 77-215 77-250 Vehicle Mileage 2734 5837 5915 Vehicle Mileage HC 2734 3386 3464 .16 • 17 .17 CO .16 .17 .18 CO? 299 302 303 2 2 2 NOx .76 .41 .55 Fuel Economy ^ MPG H9SOA 29 29 29 .6 .3 33.0 .2 38.3 % Conversion 37.4 43.8 mgm per mile , values normalized to .030% sulfurized fuel. ------- 18 Table 3C Union Carbide Catalyst Highway Cycle Mass Emissions grains per mile Test Number 76-3313 76-3521 76-3547 76-3580 Vehicle Mileage 3268 4971 5049 5130 Fuel System Economy Mileage HC CO C00 NOx MPG H^SQ^* 344 .40 1.03 287 2.90 30.6 2047 .52 .88 303 29.0 8.2 2125 .42 .93 302 2.76 29.1 4.2 2206 .42 .75 271 2.42 32.4 9.8 % Conversion 9.2 4.7 12.3 * mgm per mile , values normalized to .030% sulfurized fuel. ------- 19 Table 4A No sulfate emissions taken on vehicle without catalyst. Table 4B Factory Catalyst Sulfate Cycle Mass Emissions grams per mile Test Number 77-213 77-214 77-216 77-217 77-248 77-249 77-251 77-252 Vehicle Mileage 5810 5823 5847 5860 5886 5901 5925 5938 System Mileage 3359 3372 3396 3409 3435 3450 3474 3487 HC .19 .19 .17 .16 .17 .17 .17 .18 CO .33 .23 .27 .28 .29 .32 .28 .50 co2 333 322 332 325 321 333 324 330 NOx 2.50 2.51 2.50 2.46 2.52 2.59 2.46 2.42 Fuel Economy MPG 26.6 27.5 26.6 27.2 27.5 26.5 27.3 26.8 H SO * 20.6 23.2 25.9 30.4 21.9 29.4 39.4 28.8 % Conversion 2L.2 24.7 26.7 32.0 23.3 30.1 i 41.7 29.9 mgm per mile HjSO,, values normalized to .030% sulfurized fuel. ------- 20 Table 4C Union Carbide Catalyst Sulfate Cycle Mass Emissions grams per mile Test Number 76-3519 76-3520 76-3522 76-3523 76-3545 76-3546 76-3548 76-3549 76-3578 76-3579 76-3581 76-3582 Vehicle Mileage 4945 4958 4981 4994 5020 5035 5059 5072 5104 5117 5140 5153 System Mileage 2021 2034 2057 2070 2096 2111 2135 2148 2180 2193 2116 2229 HC .61 .60 .63 .63 .42 .43 .45 .43 .44 .44 .44 .45 CO 1.81 1.68 1.24 1.45 1.71 1.47 1.63 1.58 1.35 1.37 1.32 1.31 co2 340 323 307 313 303 312 309 291 292 282 298 304 NOx 2.40 2.61 2.64 2.47 2.41 2.22 2.41 2.33 Fuel Economy MPG 25.7 27.1 28.5 28.0 28.9 28.1 28.4 30.1 30.0 31.0 29.4 28.8 H0SO,* 6.0 3.2 5.2 6.9 4.1 5.2 8.2 6.0 6.7 6.8 7.3 7.3 % Conversion 5.0 3.4 5.8 7.5 4.7 5.6 9.7 7.0 8.0 8.4 8.4 8.1 mgm H~SO, per mile, values normalized to .030% sulfurized fuel. ------- 21 Table 5A Baseline Steady State Emissions grams per mile Test Vehicle System Speed Fuel Economy Number 76-3119* 76-3120* 76-3121 76-3122 76-3123 76-3124 Mileage 2813 2814 2816 2821 2828 2839 * grams per minute Mileage MPH Idle N Idle D 15 30 45 60 , gallons per hour HC .11 .21 .64 .77 .79 .65 Table Factory Catalyst Steady grams per \ Test Number 76-3100* 76-3101* 76-3102 76-3103 76-3104 76-3105 Vehicle Mileage 2748 2751 2753 2756 2797 2770 System Speed Mileage MPH 2748 Idle N 2751 Idle D 2753 15 2756 30 2797 45 2770 60 HC .02 .03 .10 .10 .13 .16 CO 2.98 6.10 24.35 23.53 3.00 1.05 C09 56 49 326 230 259 296 NOx .02 .02 ^.26 2.04 1.17 3.81 MPG 29.3 30.0 24.2 32.9 33.3 29.6 5B State Mass Emissions mile CO .01 .01 .11 .09 .09 .14 co2 63 63 334 269 267 312 NOx .03 .03 .28 2.53 1.24 3.90 Fuel Economy MPG .42 .43 26.5 32.9 33.1 28.4 * grams per minute, gallons per hour ------- 22 Table 5C Union Carbide Catalyst Steady State Mass Emissions grains per mile Test Number 76-3322* 76-3323* 76-3324 76-3325 76-3326 76-3327 Vehicle Mileage 3277 3277 3278 3281 3284 3292 System Mileage 353 353 354 357 360 368 Speed MPH Idle N Idle D 15 30 45 60 HC .04 .08 .37 .36 .39 .33 CO .36 .72 4.86 4.72 1.05 .81 co2 60 54 317 262 295 308 NOx .03 .04 .25 2.12 1.04 3.68 Fuel 27 32 33 28 Economy MPG .41 .38 .2 .8 .1 .6 grams per mile, gallons per hour ------- |