Microwave-assisted esterification and transesterification of dairy scum oil for biodiesel production: kinetics and optimisation studies
Prakash Binnal, A. Amruth, M. P. Basawaraj, T. S. Chethan, K. R. Shadakshara Murthy, S. Rajashekhara
Abstract
In the present study, a lab-scale microwave reactor was used to conduct the esterification and transesterification of dairy scum oil (DSO). The optimum parameters for acid-catalysed esterification were microwave power–600 W, molar ratio of methanol to FFA–30:1, temperature of reaction–60°C, concentration of sulphuric acid–8 wt%, while the optimum parameters for transesterification were temperature– 60°C, microwave power – 600 W, molar ratio of methanol to DSO– 7:1, concentration of KOH – 1 wt%. Experiments conducted under optimum conditions in the microwave reactor revealed that the highest conversion of FFA was 93.63% (reaction time – 16 min), while the highest yield of FAMEs in transesterification was 93.47% (reaction time – 5 min). Kinetic studies conducted in the microwave reactor demonstrated that esterification and transesterification followed pseudo-first-order kinetics.