CHAPTER 10: Enzymatic Reactive Absorption and Distillation

In this work, innovative concepts for reactive separation processes, such as reactive absorption and distillation, that make use of bio-based catalysts, in specific enzymes, are discussed. Enzymatic Reactive Absorption (ERA) and Distillation (ERD) offer potential for energy and investment savings or improved selectivity by exploiting enzyme merits like high enantioselectivity and high reaction rates at milder reaction conditions than chemical catalysts. Potential process equipment, application strategies to supply enzyme for ERA and ERD processes as well as suitable modeling and design approaches are presented. Despite the huge potential, addressing these issues is crucial in order to promote ERA and ERD as vital technologies for process intensification in bio-based industries. The application of the enzyme carbonic anhydrase in an ERA column with common MDEA-based solvent can drastically improve the absorption of CO₂ by more than 9-fold. Furthermore, the production of butyl butyrate and enantiomerically pure (R)-1-phenylethyl acetate or (S)-2-pentanol were successfully demonstrated in an ERD column. These processes provided high conversion rates of the substrates and purities of the product stream at milder process conditions compared to conventional processes.