Preparation of activated carbon supported Fe-Al2O3 catalyst and its application for hydrogen production by catalytic methane decomposition

Activated carbon (AC) supported Fe-Al2O3 catalysts were prepared by impregnation method and used for catalytic methane decomposition to hydrogen. The XRD and H2-TPR results showed that ferric nitrate on AC support was directly reduced to Fe metal by the reducibility of carbon at 870 °C. The loading amount and Fe/Al2O3 weight ratio affect the textural properties and catalytic methane decomposition. The surface area and pore volume of the catalyst decrease with the loading of Fe and Al2O3. Mesopores with size of about 4.5 nm can be formed at the loading of 20-60% and promote the catalytic activity and stability. The mesopores formation is thought that Fe accelerates burning off of carbon wall and enlarging pore sizes during the pretreatment. When the Fe/Al2O3 ratio is 16/24 to 24/16 at the loading of 40%, the resultant catalysts show narrow mesopore distributions and relative high methane conversion. Al2O3 as the promoter can improve catalytic activity and shorten transitional period of AC supported Fe catalyst.