The alcohol-modified CuZnAl hydroxycarbonate synthesis as a convenient preparation route of high activity Cu/ZnO/Al_2O_3 catalysts for WGS

摘要

The influence of the hydroxycarbonate precursors precipitation environment on the physico-chemical properties and catalytic activity in low-temperature water-gas shift (LT-WGS) reaction of Cu/ZnO/Al2O3 system has been studied. With the use of co-precipitation three precursors were obtained, which differed in the reactive medium, i.e. the solvent composition. Water, glycol aqueous solution or ethanol aqueous solution were used as the reactive medium. The prepared materials were characterized by means of XRF, XRD, BET, TG/MS, TPR, N2O titration techniques as well as SEM method and their catalytic activity was compared in LT-WGS reaction in the kinetic regime and differential conditions. It was shown that Cu/ZnO/Al2O3 system of higher activity can be obtained by means of alcohol assisted technique rather than using a conventional method. Precursor synthesis performed in ethanol aqueous solution contributes to obtaining highly active and stable catalysts. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.