An experimental investigation of the performance of biodiesel production techniques: Optimization, kinetics, and energy analysis

Abstract

The present research work aims to compare performance amongst biodiesel production techniques such as conventional Mechanical Stirring method (MS) and the most common process intensification techniques (viz. Microwave irradiation (MW) and Ultrasonic cavitation (US)). The performances of these techniques were evaluated and compared in terms of optimized process conditions, biodiesel yield, energy efficiency, reaction kinetics, and fuel properties. Experiments were designed and performed for each production technique using Response Surface Methodology (RSM) based Box Behnken design (BB-design) method. The optimized parameters were set for all three techniques and the maximum biodiesel yield obtained were 88.03%, 98.00%, and 96.45% for MS, US, and MW respectively. Reaction kinetics follow pseudo-first-order kinetics as noted in all three techniques. The activation energy was observed to be significantly lower for US (21.36 kJ/mol) and MW (13.05 kJ/mol) as compared to the MS (33.17 kJ/mol). Scale-up study up to tenfold increase in batch size was performed on PI techniques. The energy analysis showed that US and MW techniques are more energy-efficient than MS to produce maximum biodiesel yield.