Combination of Reaction and Separation in Heterogeneous Catalytic Hydrogenation of Ethylformate

Abstract

Continuous hydrogenation reaction of ethyl benzoylformate was studied over a (–)‐cinchonidine (CD)‐modified Pt/Al2O3 catalyst. The catalyst showed a good stability, and high enantioselectivity was achieved in the fixed‐bed reactor. Chromatographic separation of (R)‐ and (S)‐ethyl mandelate originating from a post‐continuous hydrogenation reaction of ethyl benzoylformate over the (–)‐CD‐modified Pt/Al2O3 catalyst was investigated in the same reaction mixture. A commercial column filled with a chiral selector resin was chosen as a perspective preparative‐scale adsorbent. Since adsorption equilibrium isotherms were linear within the entire investigated range of concentrations, they were determined by pulse experiments for the isomers present in a post‐reaction mixture. Breakthrough curves were measured and described successfully by the dispersive plug‐flow model with linear driving force approximation.

Integration of simulated moving bed chromatography and enzymatic racemization for the production of single enantiomers

“…Please note that such an installation can flexibly produce both enantiomers in high yield, depending only on which of the available ports is used for product removal. In principle, the NF unit can be placed at different positions in the process (Martin et al, 2015;Siitonen et al, 2015). The selected position has distinct advantages for EMR operation as it features the largest concentration difference and residence times.…”