Borgschulte A.,Laboratory of Advanced Analytical Technologies |
Callini E.,Laboratory for Hydrogen and Energy |
Stadie N.,Laboratory for Hydrogen and Energy |
Arroyo Y.,Empa - Swiss Federal Laboratories for Materials Science and Technology |
And 6 more authors.
Catalysis Science and Technology | Year: 2015
We demonstrate that the kinetics of the Sabatier reaction catalysed by sorption catalysts depends on the nanostructure of the catalyst-sorbent system. The catalysts are prepared by ion exchange of a nickel nitrate solution in two zeolites with different pore sizes. Besides their different pore sizes - which enables or hinders the adsorption of the reactants, intermediates and products in the inner of the crystallites - the catalyst systems have slightly different size distributions of the Ni-particles. By studying various catalysts with different Ni-contents we can attribute different catalytic activity and in particular the shape selectivity of the zeolite support. Therefore we focus on the microstructural characterization of the catalyst. We observe that the selectivity for methane is greatly enhanced if the pore size of the support is larger than 5 Å, while pore sizes of less than 3 Å reduce the overall conversion rate and the selectivity for methane. Thus, Ni on 3A zeolites can be used as low temperature catalysts for the reversed water-gas shift reaction to produce carbon monoxide. © The Royal Society of Chemistry 2015.
Borgschulte A.,Laboratory for Hydrogen and Energy |
Gallandat N.,Laboratory for Hydrogen and Energy |
Probst B.,Laboratory for Hydrogen and Energy |
Suter R.,Laboratory for Hydrogen and Energy |
And 6 more authors.
Physical Chemistry Chemical Physics | Year: 2013
The transformation from the fatuous consumption of fossil energy towards a sustainable energy circle is most easily marketable by not changing the underlying energy carrier but generating it from renewable energy. Hydrocarbons can be principally produced from renewable hydrogen and carbon dioxide collected by biomass. However, research is needed to increase the energetic and economic efficiency of the process. We demonstrate the enhancement of CO2 methanation by sorption enhanced catalysis. The preparation and catalytic activity of sorption catalysts based on Ni particles in zeolites is reported. The functioning of the sorption catalysis is discussed together with the determination of the reaction mechanism, providing implications for new ways in catalysis. © 2013 the Owner Societies.