Immobilized lipase‐catalysed production of alkyl esters of restaurant grease as biodiesel

Abstract

Simple alkyl ester derivatives of restaurant grease were prepared using immobilized lipases as biocatalysts. The lipases studied included those of Thermomyces lanuginosa and Candida antarctica supported on granulated silica (gran- T.l. and gran- C.a., respectively), C. antarctica supported on a macroporous acrylic resin (SP435) and Pseudomonas cepacia immobilized within a phyllosilicate sol-gel matrix (IM PS-30). All alcoholysis reactions were carried out in solvent-free media employing a one-step addition of the alcohol to the reaction system. Of the lipases studied, IM PS-30 was found to be the most effective in catalysing the methanolysis and ethanolysis of grease. The processes catalysed by gran- T.l. and gran- C.a. lipases gave poor conversions to esters, and the SP435-catalysed reactions gave intermediate yields of ethyl and methyl esters. Water activity (a(w)) was an important factor in the methanolysis reactions; reaction media with a(w)<0.5 resulted in the highest conversions to methyl esters. Molecular sieves also improved methyl ester yields by as much as 20% in transesterification reactions catalysed by IM PS-30. The immobilized lipases also were evaluated for their ability to produce alkyl esters of grease with several additional normal and branched-chain alcohols.

Combi-protein coated microcrystals of lipases for production of biodiesel from oil from spent coffee grounds

“…Such an approach solves the waste disposal problem and simultaneously yields a valuable product. The use of spent restaurant grease/oils for producing biodiesel has been one such approach [32][33][34].…”

Biodiesel Fuel Production by Enzymatic Transesterification of Oils: Recent Trends, Challenges and Future Perspectives

“…In these cases, molecular sieves are used for the control of water activity and increase ester yields by removing water produced by esterification. However, when lipases are immobilized on hydrophilic support, the molecular sieves are not needed, since, in that case, they have a negligible impact on methyl esters yield (Hsu et al, 2002). There are many possible raw materials with a potential to obtain biodiesel.…”

“…However, recent advances in materials synthesis have allowed the preparation of an efficient immobilized lipase system suitable for designing a bioreactor for the continuous production of biodiesel. Namely, Hsu et al (2002) have developed an original procedure to entrap lipase from P. cepacia (PS-30) within a phyllosilicate sol-gel matrix (IM PS-30) (Hsu et al 2002;. Lipase prepared in this way exhibit remarkable stability under normally denaturing conditions.…”

“…Namely, the immobilized IM PS-30 lipase has shown to be more active biocatalyst and gave higher conversion to ester than both commercial C. antarctica lipase supported on a macroporous acrylic resin and P. cepacia lipase supported physically on granulated silica. The immobilized Burkholderia cepacia was used in transesterification of soybean oil and a conversion of around 95% after 48 h of reaction was achieved (Hsu et al, 2002).…”

Pure silica nanoparticles for liposome/lipase system encapsulation: Application in biodiesel production

“…In fact, the homogeneous basic transesterification shows a very fast kinetic of reaction but, also, a collateral saponification reaction that reduces the biodiesel production efficiency (low biodiesel yield [4]. Again, studies concerning the production of esters by transesterification of oils recycled from restaurants using lipase from P. cepacea as catalyst, free and entrapped in a sol-gel matrix, have been carried out [5]. Several solid materials, such as ceramics, kaolinites, silica, cellulose, polymers, zeolites and mesoporous matrixes have been used as support for enzymes immobilization [6][7][8][9].…”