Evaluation of Catalytic Performance of Different Bioresoursed Silica-Based Systems to be Used in Hydrogen production from Methane

Abstract

Highly pure amorphous nanosilica was successively extracted from rice husk and tested as catalyst support for NiO particles during methane decomposition reaction. The catalytic performance of the Ni/SiO2 catalyst was significantly changed by adding Al, Mg, La and Ce oxides to SiO2 support. The TPR results demonstrated that the addition of secondary oxide to SiO2 promoted the NiO dispersion with different extents. The catalytic activity and stability of the catalysts were primarily dependent on the nature of the support. Except Ni/SiO2-CeO2, all Ni-based catalysts exhibited higher activity at the initial period of reaction, thereafter, the catalytic activity and stability decreased with increasing the reaction time. This behavior could be attributed to the decrease in the number of accessible active Ni0 sites due to the deposition of carbon on their surfaces, which could isolate the active sites and/or caused pore plugging, preventing the access of fresh CH4 to the catalyst surface. The experimental resu