US EPA

1399816 

Journal Article 

Biocatalytic esterification of palm oil fatty acids for biodiesel production using glycine-based cross-linked protein coated microcrystalline lipase 

Raita, M; Laothanachareon, T; Champreda, V; Laosiripojana, N 

2011 

Yes 

Journal of Molecular Catalysis B: Enzymatic
ISSN: 1381-1177 

73 

1-4 

74-79 

10.1016/j.molcatb.2011.07.020 

WOS:000296115700012 

Conversion of feedstocks containing high free fatty acid
contents to alkyl esters is limited by the currently used alkali-catalyzed biodiesel synthesis
process. In this study, esterification of palm fatty acids to ethyl esters was studied using
heterogeneous cross-linked protein coated microcrystalline (CL-PCMC) lipase. Optimization of
biocatalyst synthesis by variation of matrix components and organic solvents showed that highly
active CL-PCMCs could be prepared from Thermomyces lanuginosus lipase with glycine as the core
matrix in acetone. The optimized reaction contained 20% (w/w) glycine-based CL-PCMC-lipase, a 1:4
fatty acid molar equivalence to ethanol in the presence of an equimolar amount of tert-butanol
which led to production of 87.2% and 81.4% (mol/mol) of ethyl ester from palmitic acid and
industrial palm fatty acid distillate (PFAD), respectively after incubation at 50 degrees C for
6h. CL-PCMC-lipase is more catalytically efficient than protein coated microcrystalline (PCMC)
lipase, Novozyme (R) 435 and Lipolase 100T for both free fatty acids and palm fatty acid
distillate. The CL-PCMC-lipase showed high operational stability with no significant loss in
product yield after 8 consecutive batch cycles. The glycine-based microcrystalline lipase is thus
a promising alternative economical biocatalyst for biodiesel production from inexpensive
feedstocks with high free fatty acid contents. (C) 2011 Elsevier B.V. All rights reserved. 

Biodiesel; Crosslinked protein coated microcrystals; Esterification; Lipase; Palm fatty acid distillate