ABSTRACT
The idea of using vegetable oil as a substitute for diesel fuel was demonstrated by the inventor of the diesel engine, Rudolph Diesel, around 1900. Since that time, the concept of using fats and oils as renewable fuels has been periodically reintroduced, most recently during the fuel shortages of the 1970s. Since then, research in this area has continued, with various vegetable-and animal-fat-derived biofuels having been widely tested as alternative diesel fuels [1]. To overcome problems (high viscosity and fuel injector fouling) associated with the use of intact triglycerides as diesel fuels, the oil and/or fat is converted to simple alkyl esters (primarily methyl and ethyl esters). Today, “biodiesel” is the term applied to simple alkyl fatty acid esters used as alternatives to petroleum-based diesel fuels.
