The Impact of Ethanol Fuel Blends on PM Emissions from a Light-Duty GDI Vehicle

• Published in: Aerosol science and technology 2012-05, Vol.46 (5), p.576-583
• Main Authors: Maricq, M. Matti, Szente, Joseph J., Jahr, Ken
• Format: Article
• Language: English
• Subjects: Aerosols; Blends; Chemistry; Colloidal state and disperse state; Emission analysis; Engines; Ethanol; Ethyl alcohol; Exact sciences and technology; Fuels; General and physical chemistry
• ISSN: 0278-6826; 1521-7388
• DOI: 10.1080/02786826.2011.648780

This study explores the influence of ethanol on particulate matter (PM) emissions from gasoline direct injection (GDI) vehicles, a technology introduced to improve fuel economy and lower CO 2 emissions, but facing challenges to meet next-generation emissions standards. Because PM formation in GDI engines is sensitive to a number of operating parameters, two engine calibrations are examined to gauge the robustness of the results. As the ethanol level in gasoline increases from 0% to 20%, there is possibly a small (30%, there is a statistically significant 30%-45% reduction in PM mass and number emissions observed for both engine calibrations. Particle size is unaffected by ethanol level. PM composition is primarily elemental carbon; the organic fraction increases from ∼5% for E0 to 15% for E45 fuel. Engine-out hydrocarbon and NO x emissions exhibit 10-20% decreases, consistent with oxygenated fuel additives. These results are discussed in the context of the changing commercial fuel and engine technology landscapes. Copyright 2012 American Association for Aerosol Research