Process integration involving lipase-catalyzed ester synthesis reactions

The technical feasibility of integrating bioconversion (using a lipase from Mucor miehei immobilized by ion exchange onto a macroporous resin) and product recovery (via mass transfer towards liquid/vapor equilibrium) was experimentally verified for the production of ethyl acetate from acetic acid and ethanol at 30 and 40 °C. The configuration selected consisted of a packed bed thermostatted reactor inserted between the condenser and the liquid reflux to a distillation column. The concentrations of the aforementioned components and water were measured periodically for a 9 to 10-h period. The extents of conversion of acetic acid ranged from 1 to 32% at 30 °C, and from 13 to 25% at 40 °C, and they were maximum at initial molar fractions of acid of ca. 0.3 and 0.4, respectively. The ratio of the reaction product to the equilibrium reaction product increased from 2 to 32 at 30 °C, and from 5 to 27 at 40 °C when the initial molar fraction of acid in the feed increased from 0.2 to 0.7.