Methanolysis of Gmelina Seed Oil to Biodiesel with KNO3 Activated MgO-ZnO Composite Catalyst

Abstract

The present study juxtaposes for the first time the heterogeneous methanolysis of gmelina oilover KNO3 activated MgO-ZnO with a NaOH base methanolysis for biodiesel production. The conditions forbiodiesel production such as temperature, reaction time, NaOH (or KNO3 dose) and methanol-gmelina oilratio were optimised. The 4%w/w KNO3 activated MgO-ZnO afforded high biodiesel yield (71.5%) at 65 oC,predominantly consisting of C13-C25 cuts of linear fatty acid methyl esters (FAME). This heterogeneouscatalyst was characterised using X-ray diffraction (XRD), energy dispersive X-ray (EDX) analyser, scanningelectron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Gas-chromatography-massspectrometry (GC-MS) revealed the selectivity to petroselinic acid methyl ester. The fuel properties of thebiodiesel and its blends were consistent with standards. Relatively, the NaOH process yielded higherbiodiesel (96.8%) at 60oC, 90 min, 1.2% NaOH and 9:1 methanol-oil ratio.