Scalable thin-layer membrane reactor for heterogeneous and homogeneous catalytic gas–liquid reactions

Abstract

Catalytic gas–liquid reactions have potential as environmentally benign methods for organic synthesis, particularly hydrogenation and oxidation reactions. However, safety and scalability are concerns in the application of gas–liquid reactions. In this work, we develop and demonstrate a scalable, sustainable, and safe thin-layer membrane reactor for heterogeneous Pd-catalyzed hydrogenations and homogenous Cu(I)/TEMPO alcohol oxidations. The implementation of a Teflon amorphous fluoroplastic (AF) membrane and porous carbon cloth in the membrane reactor provides sufficient gas–liquid mass transfer to afford superior performance compared to conventional packed-bed or trickle-bed reactors. The membrane separates the gas from the liquid, which avoids the formation of explosive mixtures for oxygenation reactions and simplifies the two-phase hydrodynamics to facilitate scale-up by stacking modules, while significantly reducing gas consumption. In addition, 3-dimensional simulations deliver insights into the mass transfer and hydrodynamic behavior to inform optimal membrane reactor design and operation.