Equilibrium shift, poisoning prevention, and selectivity enhancement in catalysis via dehydration of polymeric membranes

Abstract

Generation of water as a byproduct in chemical reactions is often detrimental because it lowers the yield of the target product. Although several water removal methods, using absorbents, inorganic membranes, and additional dehydration reactions, have been proposed, there is an increasing demand for a stable and simple system that can selectively remove water over a wide range of reaction temperatures. Herein we report a thermally rearranged polybenzoxazole hollow fiber membrane with good water permselectivity and stability at reaction temperatures of up to 400 °C. Common reaction engineering challenges, such as those due to equilibrium limits, catalyst deactivation, and water-based side reactions, have been addressed using this membrane in a reactor.

The Efficient Utilization of Carbon Dioxide in a Power-to-Liquid Process: An Overview

“…More specifically, water is one of the primary byproducts of the FT synthesis reaction and its accumulation can significantly reduce the driving force of the reaction, easily resulting in catalyst deactivation [120]. To address these issues, Hyeon et al removed the water in situ by using a thermally rearranged polybenzoxazole membrane (See Figure 3), and found that the selectivity of the targeted low-carbon olefins was improved by 2~6% [121]. The aforementioned membrane reactors are still in their research and development stage and have a long way to go before their large-scale deployment.…”