Highly active copper catalyst for low-temperature water-gas shift reaction prepared via a Cu-Mn spinel oxide precursor

Abstract

The effect of preparation method on structural properties and activity of Cu-Mn spinel oxide catalysts for the low-temperature water-gas shift reaction (LT-WGSR) has been studied. Single-step urea-combustion and coprecipitation procedures were used for synthesis of the catalysts. Catalyst characterization was performed by N2 physisorption, XRD, HRTEM, CO-TPR, CO-TPD and FTIR spectroscopy. The WGS activity was evaluated in a conventional flow reactor in the temperature range of 140–240°C. The influence of reaction gas mixture, including either idealized or realistic reformate, H2O/CO ratio and contact time on activity were investigated. The catalytic activity tests carried out with both idealized and realistic reformate demonstrated the superior performance of the catalyst prepared by the single-step urea-combustion method. Moreover, comparison of the WGS activity of these catalysts with the one of a commercial CuO-ZnO-Al2O3 catalyst points out the potential application of Cu-Mn spinel oxide catalysts in LT-WGSR. The results revealed that the urea-combustion synthesis method is more appropriate than coprecipitation for the preparation of active and stable Cu-Mn spinel oxide catalysts for LT-WGSR.