Comparative study of NOx emissions of biodiesel-diesel blends from soybean, palm and waste frying oils using methyl and ethyl transesterification routes
20% soybean methyl ester presented lowest emissions compared to the reference fuel. Blends with palm ethyl ester were amongst blends with best emissions at all loads. 20% palm methyl ester had the highest NOx emissions. Waste frying oils increase NOx emissions comparing to diesel. Ethyl esters blends showed lower NOx emissions than methyl esters blends.