Low cost catalysts for Water Gas Shift reaction based on CuNi over La promoted ceria

Abstract

Proton-exchange membrane fuel cells are of great interest for vehicular applications. A highly pure, sustainably obtained H2 stream is desirable to use as the cell feed. In the water gas shift (WGS) process, large amounts of CO, which is a poison for the cell anode, are removed from a bioalcohol-derived H2 stream before it enters the cell. In this study, Cu–Ni catalysts supported on La-doped ceria were analyzed and studied in the WGS reaction. The supports were prepared by the urea thermal decomposition method with different percentages of La as a promoter of ceria. The metal phase was incorporated by incipient wet impregnation. Many characterization techniques were employed in this work (BET, XRD, SEM, ICP, TPR, OSC), and the relationship between the resulting properties and catalytic performance was investigated to determine the effect of La. A mixture of Cu and Ni was found to be the most effective active phase, having considerable activity and selectivity towards the desired reaction. Low degrees of La doping in ceria enhance oxygen mobility in the lattice. A commercial Ce salt containing La as its main impurity (ca. 2 %) is a convenient precursor, given its good performance and low cost compared to a high-purity salt.