lipase immobilized into novel gptms: tmos derived sol-gels and its application for biodiesel production from waste oil

In this essay, lipase from burkholderia cepacia was immobilized into 3- glycidoxypropyltrimethoxysilane (gptms) and tetramethoxysilane (tmos) derived sol-gels. gptms:tmos molar ratio of 1:3 was found to yield the best result. the morphological characteristics were investigated based on sem and bet analysis. sample mean pore diameter was 39.1 nm, it had a specific surface area of 60 m2/g prior to enzyme addition which decreased to 7.49 m2/g after immobilization. the enzyme activity was assessed through transesterification of waste cooking oil in the presence of ethanol with optimal conditions of: 40ᵒc, 15% immobilized lipase, 9:1 alcohol to oil molar ratio in 24 h of reaction which resulted in 91.70% biodiesel production. in 6-hour reaction time, 86.87% biodiesel was obtained which is much shorter than conventional enzymatic transesterification which is 72 h. ethyl esters were characterized by determining their viscosity, density, and flash point based on astm d 6751-07b standards.