A comparative study of biodiesel production by microwave assisted and conventional transesterification methods

Abstract

Nowaday’s use of biofuels for both power generation and automobiles is more relevant because of the need for energy security, environmental concerns, foreign exchange savings and socio-economic issues. Non-edible oils are considered as second generation alternative fuels and use of these oils avoids conflict between food and energy security. Therefore various locally available vegetable oils of edible and nonedible nature were selected for their biodiesel production. Subsequent characterization of these biodiesels was carried out to ensure their suitability as alternative fuels in diesel engines. Subsequently characterization of both raw vegetable oils and their respective biodiesels was done according to ASTM standards. The experimental investigation also suggests that the fuel processing with conventional transesterification method is a laborious and time consuming one. On the other hand microwave assisted transesterification (MATM) is found to be better in terms of shorter reaction time, lower consumption of power and resources compared to conventional transesterification process. MATM method reduces the reaction time drastically for both edible and non-edible oils. For edible oils the reaction time is found to be 1 minute while for nonedible oils it varies from 3 to 6 minutes. The biodiesel production from pressure reactor uses same resources required by the conventional transesterification method [CTM], but it is conducted in a closed vessel. This feature enhances the chemical kinetics, thereby reducing the reaction time up to 66% compared to conventional method.