Biocatalytic alternative for bio-glycerol conversion with alkyl carbonates via a lipase-linked magnetic nano-particles assisted process

Bio-glycerol (B-Gly) was converted to glycerol carbonate (GlyC) as an important added-value product using an advanced biocatalytic process involving the glycerol (Gly) carbonylation with dimethyl carbonate (DMC) assisted by a heterogeneous enzyme biocatalyst (lipase covalently attached on magnetic nano-particles surface). The biocatalytic process was set up optimizing the experimental parameters (e.g. molar ratio of the reagents, temperature, incubation time and catalyst content). In addition, the efficiency of DMC as carbonylation agent was evaluated against diethyl carbonate (DEC) and dibenzyl carbonate (DBC). B-Gly was tested as a raw material for GlyC synthesis in the set up biocatalytic process using commercial pure Gly (S-Gly) as reference. B-Gly was produced based on a conventional transesterification process applied to both crude and residual sun-flower oil. Crude sun-flower oil was the typical commercial one and residual sun-flower oil was that recovered from the cooking process. Comparable performances were obtained using B-Gly from residual oil and S-Gly (e.g. conversion of Gly of 36% and 45% for selectivity in GlyC of 90% and 92%, respectively), while the use of B-Gly from crude residual oil led to a Gly conversion of only 27% with selectivity in GlyC of 95%. (C) 2013 Elsevier B.V. All rights reserved.