International Journal of Hydrogen Energy, Vol.44, No.38, 21010-21019, 2019
Hydrogen production by steam reforming of methane over nickel based structured catalysts supported on calcium aluminate modified SiC
Steam reforming of methane (SRM) is an immensely important process for the production of hydrogen and syngas (H-2, CO). Ni-based alumina supported catalysts are conventionally used in the SRM process, but the coke formation and sintering are still challenging problems to develop an economical process. It was reported that the Lewis basicity of the support obviously plays a crucial role to prevent the coke formation, and basic supports such as calcium aluminate (CA(x)) has shown superior resistance for carbon deposition, but in case of CA(x) the major drawback is low thermal conductivity. In this work, in order to improve the catalytic performance of SRM, the Nickel based structured catalysts supported on the modified calcium aluminate (CA(x)) with silicon carbide (SiC) were prepared. All synthesized catalysts were characterized by various techniques including N-2-physisorption, XRD, H-2-TPR, XPS, CO2-TPR, TGA, TPH, and thermal conductivity analysis. It was found that the CA play an important role obtaining higher hydrogen yield and improved resistance to the carbon deposition. Even though, the methane conversion and H-2 yield efficiency for Ni supported on SiC modified CA(x)/Al2O3 (NASC) catalyst was slightly lower than NAS and NAC catalysts, which caused by the weak interaction of active metal, but the NASC catalyst showed superior resistance to the coke formation compared to other catalysts. It was concluded that NASC catalysts is a promising candidates for the production of hydrogen by the steam reforming of methane. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Hydrogen;Steam reforming of methane;Catalyst shaping;Calcium aluminate;Thermal conductivity;SiC