Process design and optimization of enzymatic reaction distillation

Driven by global environmental awareness, biocatalysts are playing an increasingly important role in industrial chemistry. Enzymatic reactive distillation (ERD) combines the high efficiency of enzymatic reaction and distillation separation to reduce the limiting effects of reaction equilibrium, product inhibition, and the difficulty of product recovery due to its thermodynamic constraints. The lipase CALB was immobilized and coated on the theta-ring by sol-gel method. The synthesis of n-butyl acetate by transesterification reaction was selected as the model reaction in the ERD process, and a laboratory scale column was constructed. The Rate-based RadFrac model in Aspen Plus was used to describe the ERD. The results showed that the enzyme-loaded packing showed high long-term stability after 120 days in the reaction system. The deviation of the ERD experiment and simulation results was less than 10 %, which verifies the reliability of simulation. After the parameter sensitivity optimization on the simulation, compared with the batch reactor, the ERD process increased the reactant conversion from 60 % to 94.74 %. This study established a complete process from enzyme immobilization to ERD process, which provided a theoretical basis for the establishment and optimization of ERD process.