title: Glymes as new solvents for lipase activation and biodiesel preparation.
abstract: Glymes (i.e. glycol diethers) were explored as alternative benign solvents for enzymatic reactions, specifically the lipase-catalyzed transesterification. Long-chain glymes were found highly compatible with immobilized Candida antarctica lipase B (iCALB), leading to higher enzyme activities and stabilities than t-butanol and ionic liquids (e.g. the rate of transesterification in diethylene glycol dibutyl ether (G2-Bu) was 77% higher than that in t-butanol). Furthermore, soybean oil was found fully miscible with glymes, which enabled a homogeneous reaction mixture for the enzymatic preparation of biodiesel. In the presence of glymes, CALB showed a very high tolerance to high methanol concentrations (up to 60-70% v/v), and nearly stoichiometric triglyceride conversions could be obtained under mild reaction conditions. A laboratory scale-up achieved a high conversion of soybean oil (95.5%). This study suggests that glymes can be environmentally friendly and inexpensive solvents for lipase-catalyzed reactions, such as the enzymatic preparation of biodiesel.
authors.affiliation: Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, China.
authors.forename: Shaokun
authors.initials: S
authors.lastname: Tang
authors.forename: Cecil L
authors.initials: CL
authors.lastname: Jones
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
mesh_terms: D056804:Biofuels / Q000032:analysis*; D004789:Enzyme Activation; D005019:Ethyl Ethers / Q000737:chemistry*; D008049:Lipase / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*
chemical_list: D056804:Biofuels; D005019:Ethyl Ethers; D012997:Solvents; D008049:Lipase; C024683:1,2-dimethoxyethane