CO2 methanation: catalysts for CCU technologies

Carbon dioxide capture, conversion, and storage (CCCS) technologies are emerging as pivotal solutions for utilizing carbon dioxide as a C1 building block1. An intriguing solution lies in CO2 methanation, leveraging existing methane grids globally and a clear regulatory framework. In our study, carbon dioxide methanation experiments were performed with two different setups, respectively operated at atmospheric and high-pressure. The former was used to conduct the catalyst screening while the latter was used to perform high-pressure tests and GHSV studies in a SS-316 tubular reactor. He was used as a diluent gas and N2 was used as GC internal standard. The influence of Ni-loading, supporting materials and catalyst synthesis technique on the catalytic activity were investigated. Several oxides, such as ZrO2, TiO2, MgO, Al2O3, ZSM-5, SiO2 and CeO2, were tested as supports. CeO2 showed extremely interesting performances, achieving high CO2 conversion rates at high GHSV, as shown in Figure 1. Different preparation methods, such as sol-gel, co-precipitation and wet impregnation were investigated for the preparation of the Ni/CeO2 catalyst. Several catalysts exhibited promising performance and despite the relatively high loadings, Ni catalysts emerged as viable alternatives to noble metal-based catalysts. [1] S.A. Theofanidis, A.N. Antzaras, A.A. Lemonidou, Curr. Opin. Chem. Eng. 2023, 39, 100902