High Temperature Water Permeable Membrane Reactors For Co2 Utilization

` Converting CO2 to valuable chemicals via catalytic CO2 hydrogenation presents a promising way for CO2 utilization. However, many types of CO2 hydrogenation are generally conducted under harsh conditions (T >= 200 degrees C and P >= 20 bar), yet these reactions are limited by thermodynamic equilibrium. Water is a common by-product in CO2 hydrogenation reactions. By employing a water permeable membrane reactor to simultaneously remove water from the reaction, not only favors the higher CO2 conversion by overcoming the limitation of thermodynamic equilibrium, but also protects the catalyst from deactivation caused by water. The development of a suitable membrane reactor for this application has received huge attention worldwide. However, water separation from gases (H-2, CO2, CO) under high temperature and pressure is a major challenge in developing a good performance membrane. Herein, this review contains various high temperature water/gases separating membranes, and their applications in water permeable membrane reactors for CO2 utilization. The separation and reaction mechanism in the catalytic membrane reactors are discussed in detail. Furthermore, challenges and prospects in the application of this type of catalytic membrane reactor in CO2 conversion is provided for the future development.