Catalytic membrane reactors for H₂ production and CO₂ conversion: Advanced membranes and processes

Hydrogen production and CO₂ utilization have emerged as key enablers of negative‐carbon industries, and they are often achieved through thermal catalytic reactions that require high energy consumption and associated costs. Catalytic membrane reactors (CMRs) are a promising approach for enhancing reaction efficiency in conventional packed-bed reactors (PBRs). By continuously removing one reaction product, the reaction equilibria in the CMRs can be shifted toward higher conversions, suppressing side reactions and mitigating catalyst deactivation. This review provides a comprehensive assessment of advanced membranes, including palladium alloys, silica, zeolites, and carbon molecular sieves, and process innovations, including H₂ generation by steam reforming and dehydrogenation of hydrocarbons and ammonia decomposition, and CO₂ hydrogenation to produce methanol and liquefied petroleum gas. Moreover, the interplay between simultaneous reaction and purification in these CMRs is elucidated through integrated modeling and experiments, which also sheds light on improving efficiency in other thermally catalytic reactions.