Enzyme-catalyzed production of 1-glyceryl benzoate in compressed n-butane

The aim of this work is to report the enzymatic transesterification production of 1-glyceryl benzoate in compressed n-butane, using a commercial immobilized lipase, Novozym 435. For this purpose, reaction experiments were performed on the basis of phase equilibrium data of the system methyl benzoate/n-butane, measured using the static synthetic method with a variable-volume view cell in the temperature range of 313.15-343.15 K and pressures up to 12 MPa, in the entire compositional range of n-butane. Results indicate the existence of a relatively complex phase behavior for all temperatures investigated with the occurrence of vapor-liquid and liquid-liquid phase transitions. Reaction results showed that the strategy adopted for the experimental design proved to be useful in optimizing the reaction conversion in pressurized n-butane and Novozym 435. The optimum conditions were found to be 5.5 wt% of enzyme, methyl benzoate to glycerol molar ratio of 3:1, 50 degrees C and 6 h of reaction, affording about 6% of 1-glyceryl benzoate yield. (C) 2010 Elsevier Inc. All rights reserved.