Analytical Methods Used in the Production and Fuel Quality Assessment of Biodiesel

Biodiesel, an alternative diesel fuel derived from vegetable oil, animal fats, or ivaste vegetable oils, is obtained by reacting the oil orfat with an alcohol (transesterzfication) in the presence of a basic catalyst to give the corresponding mono-alkyl esters. Two major categories of methods besides other miscellaneous ones have been reported in the literature for assessing biodiesel fuel quality andlor monitoring the transesterZfication reaction by ,vhich biodiesel is produced. The t,I'O major categories comprise chromatographic and spectroscopic methods. This article considers the various methods in each categor.v, including advantages and draWbacks, and offers suggestions on selection of appropriate methods.