Perspective on Sorption Enhanced Bifunctional Catalysts to Produce Hydrocarbons

Sorption-enhanced catalysts are bifunctional materials consisting of a heterogeneous catalyst affixed to a solid sorbent with a combined capacity to selectively capture and convert CO2 directly to value-added fuels and chemicals in the same reactor. The benefits of facile separation of CO2, directly from air or from flue gas, and conversion to chemical commodities is appealing for developing an integrated carbon capture and utilization scheme. The growth of this area is rapidly expanding with interest from catalysis, materials design, and life-cycle analysis researchers. However, the promise of sorption-enhanced catalysts is limited by their reduced thermal stability, CO2 capture capacity, and restricted product streams to C1 hydrocarbons. The prime issue is that the reaction conditions for the capture of CO2, regeneration of the sorbent, and utilization can be vastly different. It remains a challenge to optimize both the properties of the sorbent support material and the heterogeneous catalyst used. This perspective summarizes the current state-of-the-art for the properties of solid sorbents, heterogeneous catalysts, and the combined sorbent-enhanced catalysts for producing hydrocarbons from CO2. Lastly, the perspective discusses challenges and future areas for improving the performance and capture efficiency of sorption-enhanced catalysts.