Transesterification kinetics of soybean oil 1

Abstract

Abstract Transesterification of soybean oil (SBO) and other triglycerides with alcohols, in the presence of a catalyst, yields fatty esters and glycerol. Di‐ and monoglycerides are intermediates. Reactions are consecutive and reversible. Rate constants have been determined for each reaction with a computerized kinetic program. The effects of the type of alcohol, 1‐butanol or methanol (MeOH); molar ratio of alcohol to SBO; type and amount of catalyst; and reaction temperature on rate constants and kinetic order were examined. Forward reactions appear to be pseudo‐first order or second order depending upon conditions used. Reverse reactions appear to be second order. At a molar ratio of MeOH/SBO of 6:1, a shunt reaction was observed. Energy of activation was determined for all forward and reverse reactions under a variety of experimental conditions from plots of log k vs 1/T. Values ranged from 8–20 kcal/mol.