CO x-Free Hydrogen and Carbon Nanofibers Produced from Direct Decomposition of Methane on Nickel-Based Catalysts

Abstract

Direct decomposition of methane was carried out using a fixed-bed reactor at 700 °C for the production of CO x-free hydrogen and carbon nanofibers. The catalytic performance of NiO-M/SiO 2 catalysts (where M=AgO, CoO, CuO, FeO, MnO x and MoO) in methane decomposition was investigated. The experimental results indicate that among the tested catalysts, NiO/SiO 2 promoted with CuO give the highest hydrogen yield. In addition, the examination of the most suitable catalyst support, including Al 2O 3, CeO 2, La 2O 3, SiO 2, and TiO 2, shows that the decomposition of methane over NiO-CuO favors SiO 2 support. Furthermore, the optimum ratio of NiO to CuO on SiO 2 support for methane decomposition was determined. The experimental results show that the optimum weight ratio of NiO to CuO fell at 8:2 (w/w) since the highest yield of hydrogen was obtained over this catalyst.