المجلة الدولية للعلوم والتقنية

This paper discusses the enzymatic and immobilized enzymatic- transesterification for biodiesel production, describing some investigations that have been published in the literature on this theme. Part of this paper is dedicated to briefly consider other available transesterification catalysts, homogenous and heterogeneous. Though efficient in one way or another, according to the studies cited below, each catalyst category considered exhibited a certain impracticality which, in turn, negatively affects biodiesel production and/or its cost. Difficulty of isolating the product, biodiesel, from the reaction as well as lack of reusability of the homogenous catalyst were always there. To be effective, heterogeneous catalysts require employing some sort of high reaction conditions. They also suffer from catalyst deterioration due to poisoning, sintering, coking and leaching. Although enzymatic catalysts may be affirmed to present a great potential catalyst for biodiesel production; however, they are costly and require long reaction times and thorough control. Catalyst deterioration is also observed while using enzymatic catalysts for transesterification.