Kinetic studies of epoxidation and oxirane cleavage of palm olein methyl esters

The kinetics for the epoxidation of methyl esters of palm olein (MEPOL) by peroxyformic acid and peroxyacetic acid generatedin situ were studied. The rate-determining step was found to be the formation of peroxy acid. Epoxidized MEPOL (EpMEPOL), with almost complete conversion of the unsaturated carbon and negligible ring-opening, can be synthesized by thein situ technique described. The kinetics of the oxirane cleavage of EpMEPOL by acetic acid were studied at various temperatures. The reaction was found to be first-order with respect to the epoxy concentration and second-order to the acetic acid concentration. The activation energy and the entropy of activation for the epoxidation of MEPOL were comparable to those for the oxirane cleavage of EpMEPOL by acetic acid, suggesting that the two reactions are competitive. The success of the epoxidation of MEPOL with only negligible oxirane cleavage is attributed to the heterogeneous nature of the system employed in thein situ technique.