Esterification of oleic acid to biodiesel using magnetic ionic liquid_ Multi-objective optimization and kinetic study.

Abstract:

The esterification of oleic acid in the presence of magnetic ionic liquid, 1-butyl-3-methylimidazolium tetrachloroferrate ([BMIM][FeCl₄]) at reaction temperature of 65 °C has been investigated. Artificial neural network-genetic algorithm (ANN-GA) was used to simultaneously optimized methyl oleate yield and oleic acid conversion for the reaction. It was found that optimum responses for both yield and conversion were 83.4%, which can be achieved using molar ratio methanol–oleic acid of 22:1, catalyst loading of 0.003 mol and reaction time at 3.6 h. Esterification of oleic acid at optimum condition using recycled [BMIM][FeCl₄] registered not much loss in catalytic activity after six successive runs. Kinetic study indicated that the reaction followed a pseudo-first order reaction, with activation energy and pre-activation energy of 17.97 kJ/mol and 181.62 min⁻¹, respectively. These values were relatively low compared to homogeneous or heterogeneous catalysts for esterification of oleic acid. Thus, [BMIM][FeCl₄] is a promising new type of catalyst for conversion of high free fatty acid (FFA) feeds to biodiesel.

1. Ahmad Hafiidz Mohammad Fauzi and Nor Aishah Saidina Amin, Ramli Mat (2014). Esterification of oleic acid to biodiesel using magnetic ionic liquid_ Multi-objective optimization and kinetic study. Applied Energy, Volume: 114, 809-818. (2012 IF = 4.781) DOI: https://doi.org/10.1016/j.apenergy.2013.10.011