The role of additives (Ba, Zr, and Nd) on Ce/Cu/Al2O3 catalyst for water-gas shift reaction

Enhanced catalytic performance is required to increase the efficiency of hydrogen production from waste-derived synthesis gas via the high-temperature water-gas shift reaction (HT-WGSR). Herein, the effects of barium, zirconium, and neodymium doping on the physico-chemical properties of a Ce/Cu/Al2O3 catalyst as well as its catalytic performance for HT-WGSR are investigated. Ce/Cu/Al2O3 catalysts with various additives (barium, zirconium, and neodymium) prepared via a sequential impregnation method have been characterized by using N-2 adsorption-desorption isotherms, X-ray powder diffraction (XRPD), N2O-titration, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and hydrogen temperature-programmed reduction (H-2-TPR). Advantageously, barium and zirconium addition enhance the HT-WGSR activity and stability of the Ce/Cu/Al2O3 catalyst, whereas neodymium doping has a negative effect. Regarding the correlation of catalytic performance with the characterization results, it was found that catalytic activity and stability strongly depended on their oxygen vacancy concentration and strong-metal to support interaction. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.