Hydrogen Production in the Steam CO2 Reforming of Methane Ni-based Catalysts Supported on mixed MgO and SiC-Al2O3

Abstract

After the Paris Agreement to meet the net zero by 2050, many countries are making an effort to make technological developments to achieve a zero-carbon-energy-based society [1]. Nowadays, H2 holds great potential to become an alternative to fossil fuels due to its high heating value and pollution-free characteristics [2]. Syngas (a mixture of H2 and CO) is widely used in various industrial processes for producing ammonia, methanol, and liquid hydrocarbons [3]. In particular, Steam CO2 Reforming of Methane (SCR) is a promising CO2 valorization route yielding syngas with H2/CO molar ratio close to 2 which is a desirable feedstock for Fischer-Tropsch (F-T) synthesis [4]. Ni-based catalysts are widely investigated in SCR processes, but carbon deposition is causing the deactivation of catalysts. Carbon deposition may lead to deactivation on the catalyst surface by the blocking of catalyst pores and the physical decomposition of the catalyst and support [5]. It was reported that metal support interaction could be enhanced the coke deposition resistance and reduce the sintering effect by using appropriate support. In this study, it was investigated that Steam CO2 Reforming of Methane on Ni/SiC-Al Oxide and Ni/MgO-SiC-Al2O3 catalysts with various support ratios. MgO and SiC-Al2O3 supports were prepared by the sol-gel and precipitation methods, respectively. Ni-based catalysts were synthesized by an impregnation method and characterized by N2-physisorption, XRD, H2-TPR, and TPO techniques. The catalytic performance was evaluated in the fixed bed reactor under 750~850 oC and 1 bar. It was found that Ni/MgO-SiC-Al2O3 catalyst showed higher coke resistance than Ni/SiC-Al2O3 catalyst. This result shows that MgO, a representative Lewis base, can reduce carbon deposition by dissociating CO2 into CO and O, which is good for cleaning the metallic surface.