Effects of a diesel oxidation catalyst on gaseous pollutants and fine particles from an engine operating on diesel and biodiesel

Abstract

The effects of a diesel oxidation catalytic (DOC) converter on diesel engine emissions were investigated on a diesel bench at various loads for two steady-state speeds using diesel fuel and B20. The DOC was very effective in hydrocarbon (HC) and CO oxidation. Approximately 90%–95% reduction in CO and 36%–70% reduction in HC were realized using the DOC. Special attention was focused on the effects of the DOC on elemental carbon (EC) and organic carbon (OC) fractions in fine particles (PM_2.5) emitted from the diesel engine. The carbonaceous compositions of PM_2.5 were analyzed by the method of thermal/optical reflectance (TOR). The results showed that total carbon (TC), OC and EC emissions for PM_2.5 from diesel fuel were generally reduced by the DOC. For diesel fuel, TC emissions decreased 22%–32% after the DOC depending on operating modes. The decrease in TC was attributed to 35%–97% decrease in OC and 3%–65% decrease in EC emissions. At low load, a significant increase in the OC/EC ratio of PM_2.5 was observed after the DOC. The effect of the DOC on the carbonaceous compositions in PM_2.5 from B20 showed different trends compared to diesel fuel. At low load, a slight increase in EC emissions and a significant decrease in OC/EC ratio of PM_2.5 after DOC were observed for B20.

Keywords

diesel oxidation catalyst (DOC) / diesel particulate matters / elemental carbon (EC) / organic carbon (OC) / biodiesel

References

[1] Maricq M M. Chemical characterization of particulate emissions from diesel engines: a review. Aerosol Science, 2007, 38(11): 1079–1118

[2] US Environmental Protection Agency (EPA). Health effects assessment document for diesel engine exhaust. EPA/600/8-90/057F, 2002

[3] Shi J P, Mark D, Harrison R M. Characterization of particles from a current technology heavy-duty diesel engine. Environmental Science & Technology, 2000, 34(5): 748–755

[4] Ålander T A, Leskinen A, Raunemaa T, Rantanen L. Characterization of diesel particles: effects of fuel reformulation, exhaust aftertreatment and engine operation on particle carbon composition and volatility. Environmental Science & Technology, 2004, 38(9): 2707–2714

[5] Shah S D, Cocker D R III, Miller J W, Norbeck J M. Emission rates of particulate matter and elemental and organic carbon from in-use diesel engines. Environmental Science & Technology, 2004, 38(9): 2544–2550

[6] Hosoya M, Shimoda M. The application of diesel oxidation catalysts to heavy duty diesel engines in Japan. Applied Catalysis B: Environmental, 1996, 10(1-3): 83–97

[7] Maricq M M, Chase R E, Xu N, Laing P M. The effect of the catalytic converter and fuel sulfur level on motor vehicle particulate matter emissions: light duty diesel vehicles. Environmental Science & Technology, 2002, 36(7): 283–289

[8] Shah S D, Cocker D R III, Johnson K C, Lee J M, Soriamo B L, Miller J W. Reduction of particulate matter emissions from diesel backup generators equipped with four different exhaust aftertreatment devices. Environmental Science & Technology, 2007, 40(14): 5070–5076

[9] Graboski M S, McCormick R L. Combustion of fat and vegetable oil derived fuels in diesel engines. Progress in Energy and Combustion Science, 1998, 24(2): 125–164

[10] Lapuerta M, Armas O, Rodríguez-Fernández J. Effect of biodiesel fuels on diesel engine emissions. Progress in Energy and Combustion Science, 2008, 34(2): 198–223

[11] Durbin T D, Collins J R, Norbeck J M, Smith M R. Effects of biodiesel, biodiesel blends and a synthetic diesel on emissions from light heavy-duty diesel vehicles. Environmental Science & Technology, 2002, 34(3): 349–355

[12] US Environmenral Protection Agency (EPA). A Comprehensive analysis of biodiesel impacts on exhaust emissions. Draft Technical Report EPA420-P-02–001, 2002

[13] Lee S W, Herage T, Yong B. Emission reduction potential from the combustion of soy methyl ester fuel blended with petroleum distillate fuel. Fuel, 2004, 83(11-12): 1607–1613

[14] Zhang J, He K, Shi X, Zhao Y. Effect of SME biodiesel blends on PM_2.5 emission from a heavy-duty engine. Atmospheric Environment, 2008, 43(15): 2442–2448

[15] Zhang Z H, Cheung C S, Chan T L, Yao C D. Emission reduction from diesel engine using fumigation methanol and diesel oxidation catalyst. Science of the Total Environment, 2009, 407(15): 4497–4505

[16] Vaaraslahti K, Ristimäki J, Virtanen A, Keskinen J, Giechaskiel B, Soll A A. Effect of oxidation catalysts on diesel soot particles. Environmental Science & Technology, 2006, 40(15): 4776–4781

[17] Bagley S T, Gratz L, Johnson J H, Mcdonald J F. Effects of an oxidation catalytic converter and a biodiesel fuel on the chemical, mutagenic, and particle size characteristics of emissions from a diesel engine. Environmental Science & Technology, 1998, 32(9): 1183–1191

[18] Tang S, Frank B P, Lanni T, Rideout G, Meyer N, Beregszaszy C. Unregulated emissions from a heavy-duty diesel engine with various fuels and emission control systems. Environmental Science & Technology, 2007, 41(14): 5037–5043

[19] Chow J C, Watson J G, Pritchett L C, Crow D, Lowenthal D H, Merrifield T. Comparison of IMPROVE and NIOSH carbon measurements. Aerosol Science and Technology, 2001, 34(1): 23–34

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag Berlin Heidelberg