Methanation Performance of Unsupported MoP Catalysts Prepared with Phytic Acid under Low H₂/CO

Abstract

In this paper, using phytic acid as the precursor, the effects of the reduction temperature and post-treatment conditions on the methanation performance of unsupported MoP catalysts were investigated. The synthesis mechanism and structureactivity relationship of the catalyst were investigated by correlation characterization, such as N 2 adsorption-desorption, XRD, Raman analysis, element analysis and XPS. At the reduction temperature of 650°C, MoP catalysts showed the higher methanation activity due to its smaller crystallite size and large specific surface area. After H 2 post-treatment at 750°C, the CO conversion increased by 16.2% because of the higher specific surface area and lower contents of the carbon and phosphorus species in MoP-750-H. The MoP-750-H catalysts show good stability without H 2 S. The sulfur-resistant methanation tests indicated that the inactivation of the catalysts was more serious with the higher H 2 S concentration, due to the sulfidation from MoP to MoS 2 .