Recent advances in catalytic systems for co2 conversion to substitute natural gas (SNG): perspective and challenges

It has been well established that carbon dioxide (CO2) is one of the main greenhouse gasses and a leading driver of climate change. The chemical conversion of CO2 to substitute natural gas (SNG) in the presence of renewable hydrogen is one of the most promising solutions by a well-known process called CO2 methanation. There have been comprehensive efforts in developing effective and efficient CO2 methanation catalytic systems. However, the choice of competitive and stable catalysts is still a monumental obstruction and a great challenge towards the commercialization and industrialization of CO2 methanation. It is necessary to emphasize the critical understandings of intrinsic and extrinsic interactions of catalyst components (active metal, support, promoter, etc.) for enhanced catalytic performance and stability during CO2 methanation. This study reviews the up-to-date developments on CO2 methanation catalysts and the optimal synergistic relationship between active metals, support, and promoters during the catalytic activity. The existing catalysts and their novel properties for enhanced CO2 methanation were elucidated using the state-of-the-art experimental and theoretical techniques. The selection of an appropriate synthesis method, catalytic activity for CO2 methanation, deactivation of the catalysts, and reaction mechanisms studies, have been explicitly compared and explained. Therefore, future efforts should be directed towards the sustainable developments of catalytic configurations for successful industrial applications of CO2 utilization to SNG using CO2 methanation. (C) 2021 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences