Electrochemical behaviour of Cu-Zn-Al oxide catalysts in DMSO₂ at 150°C

Abstract

The electrochemical behaviour of Cu−Zn−Al oxide catalysts in a high-temperature solvent, dimethylsulphone (DMSO₂), at 150°C has been investigated. It has been shown that CuO electroreduction becomes easier and/or deeper in the Cu−Zn−Al oxide catalysts than in CuO alone. This electroreduction occurs at higher potentials, and the overall faradic yield decreases when CO₂ in dissolved in DMSO₂ on account of a strong interaction between the reduced species formed during the electronic transfer and CO₂. These results are consistent with the characterizations of the physical and chemical properties of these catalysts. They confirm that electrochemistry is a suitable method to determine the redox states of some copper industrial catalysts used in methanol synthesis.