Biodiesel as a motor fuel

In general, the physical and chemical properties and the performance of ethyl esters are comparable to those of the methyl esters. Methyl and ethyl esters have almost the same heat content. The viscosities of the ethyl esters are slightly higher, and the cloud and pour points are slightly lower, than those of the methyl esters. Engine tests demonstrated that methyl esters produced slightly higher power and torque than ethyl esters. Some desirable attributes of the ethyl esters over methyl esters are: significantly lower smoke opacity, lower exhaust temperatures and lower pour point. The ethyl esters tended to have more
injector coking than the methyl esters . Several studies show biodiesel can run in a conventional diesel engine for an extended time. Researchers in several states including Missouri and Idaho, have run diesel engines in pickups, city buses, large trucks and tractors on various mixes of biodiesel/diesel fuel. These mixtures have ranged from 2/98% (B2), 20/80% (B20) up to 100%(B100). Standard diesel engines will operate on 100% biodiesel. In cold weather, biodiesel begins to cloud and thicken at about 272 K.