FUEL PROPERTIES AND EMISSIONS OF SOYBEAN OIL ESTERS AS DIESEL FUEL

The effects of using blends of methyl and isopropyl esters of soybean oil with No. 2 diesel fuel were studied at several steady-state operat ing conditions in a four-cylinder turbocharged diesel engine. Fuel ble nds that contained 20, 50, and 70% methyl soyate and 20 and 50% isopro pyl soyate were tested. Fuel properties, such as cetane number, also w ere investigated. Both methyl and isopropyl esters provided significan t reductions in particulate emissions compared with No. 2 diesel fuel. A blend of 50% methyl ester and 50% No. 2 diesel fuel provided a redu ction of 37% in the carbon portion of the particulates and 25% in the total particulates. The 50% blend of isopropyl ester and 50% No. 2 die sel fuel gave a 55% reduction in carbon and a 28% reduction in total p articulate emissions. Emissions of carbon monoxide and unburned hydroc arbons also were reduced significantly. Oxides of nitrogen increased b y 12%.