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1697820 
Journal Article 
Exhaust emissions from an engine fueled with biodiesel from high-oleic soybeans 
Tat, ME; Wang, PS; Van Gerpen, JonH; Clemente, TE 
2007 
Yes 
Journal of the American Oil Chemists' Society
ISSN: 0003-021X
EISSN: 1558-9331 
84 
9 
865-869 
WOS:000249072300010 
Biodiesel is a fuel comprising mono-alkyl esters of medium to long-chain fatty acids derived from vegetable oils or animal fats. Typically, engines operated on soybean-based biodiesel exhibit higher emissions of oxides of nitrogen (NOx) compared with petroleum diesel. The increase in NOx emissions might be an inherent characteristic of soybean oil's polyunsaturation, because the level of saturation is known to affect the biodiesel's cetane number, which can affect NOx. A feedstock that is mostly monounsaturated (i.e. oleate) helps to balance the tradeoff between cold flow and oxidative stability. Genetic modification has produced a soybean event, designated 335-13, with a fatty acid profile high in oleic acid (> 85%) and with reduced palmitic acid (< 4%). This high-oleic soybean oil was converted to biodiesel and run in a John Deere 4045T 4.5-L four-stroke, four-cylinder, turbocharged direct-injection diesel engine. The exhaust emissions were compared with those from conventional soybean oil biodiesel and commercial No. 2 diesel fuel. There was a significant reduction in NOx emissions (alpha = 0.05) using the high-oleic soybean biodiesel compared with regular soybean oil biodiesel. No significant differences were found between the regular and high-oleic biodiesel for unburned hydrocarbon and smoke emissions. 
genetically modified soybean; high-oleic soybean; alkyl esters; biodiesel; diesel fuel; diesel engine; diesel combustion; diesel emission; NOx emission