Selective Enzymatic Reactive Distillation for Transesterification with Open-Cell Foams and 3D Printed Packings: A Parametric Study through Experiment and Simulation

This work explores a selective continuous enzymatic reactive distillation (ERD) using innovative structured metallic packings functionalized with Candida antarctica lipase B (CALB)-loaded xerogels for the selective production of (R)-2-pentylbutyrate. Aluminum open-cell foams (10 and 20 ppi) and 3D-printed Tetra Splines were employed for the first time as packings in ERD systems, distinguishing from the usual wire gauze structures. The structure surfaces were pretreated with a GPTMS primer to significantly enhance the biocatalytic coating adhesion and stability. Continuous ERD experiments were conducted to evaluate the effects of catalyst load, packing type, feed composition, and reflux ratios, revealing minimal catalyst leaching and sustainable high catalytic activity. Reaction yields reached up to 80.8% with an excellent enantiomeric excess of 90%, successfully overcoming the thermodynamic equilibrium of the reaction. An equilibrium-stage model was developed, effectively representing the setup without its experimental flaws. Parametric analyses using this model identified key operational parameters critical for process optimization with a comprehensive understanding of their impact on the process performances. A pilot plant of the selective ERD process was then simulated based on this study. Further research is required to better understand how operating parameters affect the reduction of enzyme selectivity in ERDs and to identify strategies, potentially involving new or less conventional column designs such as ERDWC, to minimize these losses.