Microwave-Heated Tubular Reactor for Enhanced Biodiesel Transesterification Process

Biodiesel is an important renewable fuel derived from bioresources that can help to mitigate climate change by significantly reducing carbon emissions from the transportation sector. The conventional batch reactor transesterification process to produce biodiesel is inefficient due to long production time and high energy consumption. In this study, transesterification of palm oil for biodiesel production is conducted using the combined technologies of tubular reactor and microwave-assisted heating method. Parameters investigated include the effects of microwave power, methanol to oil molar ratio, KOH catalyst concentration, and tube length, on FAME yield. Fatty acid methyl ester (FAME) yield of 96.5 % meeting the EN 14214 standard were obtained within the conditions where methanol to oil molar ratio was 8.5-10.0 and microwave power was.320 to 350 W. It was observed that FAME yield reduces when excess microwave power is provided to the reaction due to overheating of organic molecules and boiling of methanol. An average increase of around 10 % in FAME yield was found when the KOH catalyst concentration increases from 0.8 to 1.2 wt%. The results of this study provide insights into the optimisation of transesterification process for producing biodiesel using the combined microwave-assisted heating in tubular reactor method.