Synthesis and utilization of mesoporous alumina as a supporting material of Ce-promoted Ni-based catalysts in the methane reforming process

Due to the large applications of hydrogen as a feedstock of chemical industries and as an energy carrier, its production on large scales with low costs has attracted researchers. Steam reforming of methane (SRM) is the most common process for producing H₂-rich syngas over Ni/Al₂O₃ catalysts, which suffer from coke deposition and Ni particles agglomeration. For overcoming these issues, we have synthesized mesoporous alumina (MA) as a supporting material of Ni particles, structure, and activity, which were compared with the bulk alumina (BA) supported catalysts in the SRM process for the first time. Besides, cerium as an appropriate promoter for lowering deposited coke was added to all prepared catalysts. The reaction temperature (600–700°C), Ni loading (10–25 wt.%), and Ce loading (1–5 wt.%) were the parameters that were optimized for maximizing H₂ yield and CH₄ conversion. Prepared samples were characterized by various techniques before and/or after reaction. The results of TEM and XRD depicted the formation of nanocrystalline and mesoporous structure for Ni-MA catalysts compare to Ni-BA samples. The observations indicated that 20Ni-3Ce/MA had the highest catalytic performance, achieving a CH₄ conversion of 91.0% and H₂ yield of 92.8% at 700°C.