Effect of Re Addition on the Water–Gas Shift Activity of Ni Catalyst Supported by Mixed Oxide Materials for H2 Production

Water–gas shift (WGS) reaction was performed over 5% Ni/CeO2, Ni/Ce-5% Sm-O, Gd-O, 1% Re 4% Sm-O and Gd-O catalysts to reduce CO concentration produce extra hydrogen. CeO2 M-doped ceria (M = Sm Gd) were prepared using a combustion method, then nickel rhenium added onto the mixed oxide supports an impregnation method. The influence of rhenium, samarium gadolinium on structural redox properties materials that have effect their water–gas activities investigated. It found addition into Ni/CeO2 enhances surface area, reduces crystallite size CeO2, increases oxygen vacancy improves Ni dispersion surface. Moreover, leads increase in WGS activity Ni/CeMO catalysts. results indicate presents greatest activity, with maximum 97% carbon monoxide conversion at 350 °C. An area metallic this catalyst facilitation reactant adsorption. result X-ray absorption near-edge structure (XANES) analysis suggests donate some electrons resulting decrease oxidation state cerium. occurrence more Ce3+ higher vacancy, which alerts process surface, thereby increasing efficiency reaction.