Integrated CO2 Capture and Conversion as an Efficient Process for Fuels from Greenhouse Gases

To mitigate climate change, the reduction of anthropogenic CO2 emissions is of paramount importance. CO2 capture and storage has been identified as a promising short- to midterm solution, yet the underground storage of CO2 faces often severe public resistance. In this regard, the conversion of the CO2 captured into useful chemicals or fuels is an attractive alternative. Here, we propose and experimentally demonstrate a process that directly integrates CO2 utilization into CO2 capture allowing for the full conversion of the CO2 captured and the selective production of a synthesis gas. The process is attractive both economically and from a process operation point of view as the coupled reactions are performed in a single reactor. The concentration of (unreacted) CO2 in the off-gas is below 0.08%, demonstrating the almost full conversion of the CO2 captured in a single, integrated step. Importantly, the process is demonstrated using a nonprecious metal catalyst and an inexpensive naturally occurring CO2 sorbent, viz., limestone.