Calcium-looping coupling methane partial oxidation and dry reforming process for integrated CO2 capture and conversion: Regulable H2/CO molar ratio and excellent coke deposition-resistant

Calcium-looping dry reforming of methane (CaLDRM) implemented on Ni-CaO dual-functional materials (DFMs) is a promising solution to achieve integrated CO2 capture and conversion. However, the sintering and coke deposition of DFMs and the difficulty of adjusting the H2/CO ratio in syngas limit the application of CaLDRM. In this work, partial oxidation of methane (POM) reaction was introduced into the CaLDRM process to form a novel Calcium-looping partial oxidation and dry reforming of methane process (CaLODRM) that relies on the developed MgO-modified Ni-CaO DFMs. The effects of different POM to DRM ratios on the reactivity and stability of MgO-modified Ni-CaO were investigated. The results demonstrated that the introduction of POM improved the resistance of the material to coke deposition and allowed the molar ratio of H2/CO in the product to be freely regulated between 1.1 and 1.43. When the DRM to POM ratio is 1:1, the coke deposition of Ni-CaMg after 10 CaLODRM cycles was only 0.0120 gcoke/gmaterial, which is less than half of the CaLDRM. Therefore, combining POM with CaLDRM is beneficial for producing syngas that meets different industrial needs and thus have good prospects for industrial applications.