Process optimization of biodiesel production from Hevea brasiliensis oil using lipase immobilized on spherical silica aerogel

In this study, biodiesel was synthesized in an enzymatic transesterification process from Hevea brasiliensis, crude non-edible oil, using lipase immobilized on spherical silica aerogels. Enzymatic transesterification is preferred to chemical methods as it is milder and is more environmentally friendly. Lipase based transesterification of Hevea brasiliensis under optimal conditions provided high FAME (fatty acid methyl esters) yields up to 93%. Response Surface Methodology (RSM) was used to optimize the process for maximum FAME yield. The maximum yield was obtained at a temperature of 35 °C, water content of 15% (v/v %) and methanol/oil molar ratio of 8:1. Percent yields of FAME from the transesterification process followed second order model. Even after 10 cycles of reuse, lipase immobilized on spherical silica aerogel showed only 10.7% reduction in percentage yield of FAME. The results from this study demonstrate the viability of economical biodiesel production using waste products as both source and catalyst.