Biodiesel production from canola oil by using lipase immobilized onto hydrophobic microporous styrene–divinylbenzene copolymer

In this study, the methyl esters of the long chain fatty acids (biodiesel) were synthesized by methanolysis of canola oil by immobilized lipase. Lipase from Thermomyces lanuginosus was immobilized by both physical adsorption and covalent attachment onto polyglutaraldehyde activated styrene–divinylbenzene (STY–DVB) copolymer, which is synthesized by using high internal phase emulsion (polyHIPE). Two different STY–DVB copolymers were evaluated: STY–DVB copolymer and STY–DVB copolymer containing polyglutaraldehyde (STY–DVB–PGA). Lipase from T. lanuginosus was immobilized with 60% and 85% yield on the hydrophobic microporous STY–DVB and STY–DVB–PGA copolymer, respectively. Biodiesel production using the latter lipase preparation was realized by a three-step addition of methanol to avoid strong substrate inhibition. Under the optimized conditions, the maximum biodiesel yield was 97% at 50 °C in 24 h reaction. The immobilized enzyme retained its activity during the 10 repeated batch reactions.