Diesel Combustion of Palm Oil Methyl Ester

Palm oil is one of vegetable oils with the potential as alternative diesel fuel because of the high productivity and low cost. In order to utilize palm oil methyl ester (PME) as an alternative diesel fuel, the combustion characteristics and exhaust emissions are investigated using both a DI diesel engine and a swirl-chamber diesel engine. The results show that the ignition delay of PME is shorter than those of rapeseed oil methyl ester (RME) and gas oil although the estimated cetane number of PME is lower than that of gas oil. NOx emission from PME is lower than those from RME and gas oil. NOx and Smoke emissions from PME are simultaneously reduced compared with gas oil. Based on the results, it is concluded that PME with shorter ignition delay is a good fuel as a diesel fuel and can be used as an alternative fuel of petroleum diesel fuels although PME has high pour point (12.5°C) that is not suitable property as a diesel fuel.