Journal
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
Volume 42, Issue 15, Pages 9858-9872Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.ijhydene.2017.03.049
Keywords
Rice husk silica; Hydrogen production; Methane decomposition; Catalyst supports; Carbon nanomaterials
Categories
Ask authors/readers for more resources
Amorphous nanosilica powder was extracted from rice husk and used as a catalyst support as well as a starting material for the preparation of different binary oxides, i.e., SiO2 Al2O3, SiO2 MgO, SiO2-CeO2 and SiO2 La2O3. A series of supported nickel catalysts with the metal loading of 50 wt % were prepared by wet impregnation method and evaluated in methane decomposition to COx -free hydrogen production. The fresh and spent catalysts were extensively characterized by different techniques. Among the evaluated catalysts, both Ni/SiO2 Al2O3 and Ni/SiO2 La2O3 catalysts were the most active with an over-all H-2 yield of ca. 80% at the initial period of the reaction. This distinguishable higher catalytic activity is mainly referred to the presence of free mobile surface NiO and/or that NiO fraction weakly interacted with the support easily reducible at low temperatures. The Ni/ SiO2-CeO2 catalyst has proven a great potential for application in the hydrogen production in terms of its catalytic stability. The formation of MgxNi(1-x)O solid solution caused the Ni/ SiO2-MgO catalyst to lose its activity and stability at a long reaction time. Various types of carbon materials were formed on the catalyst surface depending on the type of support used. TEM images of as -deposited carbon showed that multi-walled carbon nanotubes (MWCNTs) and graphene platelets were formed on Ni/SiO2, while only MWCNTs were deposited on all binary oxide supported Ni catalysts. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available