Fe-Ce-Al Catalysts for Decomposition of Methane to High Purity Hydrogen and High-Value Carbon

Catalytic methane decomposition is a promising technique for CO_x-free hydrogen production and carbon nanomaterials. In this research, iron-supported catalysts, prepared by successive wetness impregnation, were studied for methane decomposition at 700 °C. The results showed that Fe⁰ turned out to be the active site and greater metal-support interaction led to the formation of iron aluminate (FeAl₂O₄), both of which played a role in the catalytic activity performance. The 30Fe/Ce-Al catalyst performed the best catalytic activity in terms of maximum methane conversion (76%) and hydrogen production rate (1.04 mol/g_Metal/s/surface area). The observation also suggested that the 10Fe/Ce-Al catalyst significantly deactivated due to metal particle agglomeration, as evidenced by negligible weight loss in thermogravimetric analysis. In contrast, the 20Fe/Ce-Al and 30Fe/Ce-Al catalysts were deactivated from both agglomeration and carbon deposition. The surface morphology analysis of the spent catalyst indicated that the deposited carbon was multiwalled carbon nanotubes that followed the base-growth mechanism.