Integration of Enzymatic Catalysts in a Continuous Reactive Distillation Column: Reaction Kinetics and Process Simulation

Abstract

This work presents a feasibility study for an enzymatic reaction in a continuously operated reactive distillation column. As a model reaction, the transesterification of ethyl butyrate with n-butanol in the presence of lipase CALB was considered. For use in the distillation column, lipase CALB was immobilized by entrapment in a hydrophobic silica xerogel and introduced as granulate into the catalytic packing Katapak-SP-11. The reaction kinetics was experimentally determined for different concentration and temperature ranges and described by means of the Michaelis−Menten double-substrate kinetic model in combination with the Arrhenius model. With these kinetic data, process simulations were carried out with an Aspen Custom Modeler nonequilibrium-stage model validated for a DN50 pilot-scale column. The concentration of n-butanol in the reactive section was maintained low to decrease the inhibiting effects on the enzyme. For an optimized setup and operating conditions, conversion rates of more than 90% were achieved for n-butanol and 26% for ethyl butyrate. These results clearly demonstrate that lipase CALB can be applied in a continuously operated reactive distillation column.

Pilot-scale validation of Enzymatic Reactive Distillation for butyl butyrate production

“…This model was extended with physical properties of the used components [20] and kinetic data based on a recent publication [21]. Furthermore, the operating window is described in which the ERD is feasible for experimental investigations and simulation.…”

“…The collection of fundamental data including property data [20] and the reaction kinetics [21] was presented recently. In this paper, we address the investigations of packing properties, we identify the operating window and we develop a mathematical model, followed by experiments which were carried out in a pilot-scale ERD column and a conventional distillation column.…”

“…More information about the vapor-liquidequilibrium (VLE) data and the property method are available in Heils et al (2014) [20].…”

Techno-economic evaluation of an ultrasound-assisted Enzymatic Reactive Distillation process

“…Process intensification (PI) in distillation aims at further increasing the sustainability, eco-2 efficiency, production efficiency and yield of industrial processes (Lutze and Górak, 2013 gel, which was applied as coating on structured packing (Heils et al, 2014;Heils et al, 2012). 22…”

“…Furthermore the feasibility of the ERD was demonstrated with help of an ERD model-based 23 analysis and with experiments in a batch ERD set-up (Heils et al, 2014;Heils et al, 2012). A 24 continuous ERD process for the transesterification of EtBu was investigated by Wierschem et 25 al.…”