High-surface-area activated red mud supported Co3O4 catalysts for efficient catalytic oxidation of CO

Abstract

High-surface-area activated red mud (ARM) was obtained by an acid digestion and alkali reprecipitation process, which was further used as the support of Co₃O₄ catalysts. The prepared Co/ARM catalysts possess high surface area and well-defined mesostructure, which are active for CO oxidation. The XRD, SEM, TEM, FT-IR, TG, H₂-TPR, and XPS characterization results reveal that the Co₃O₄ particles were formed and finely dispersed on the ARM surface. The effects of the Co contents and calcination temperatures on the catalytic behavior of the Co/ARM catalysts were detailedly investigated. The 300 °C-calcined Co/ARM catalyst with 20 wt% Co content exhibited the highest catalytic activity and good stability, which can be attributed to the features of highly dispersed Co₃O₄ nanoparticles, large surface area and rich porosity, and ultra high oxygen content of the catalyst. Furthermore, this catalyst is derived from industry waste residue, has much low cost, and can be used as a promising catalyst in various catalytic reactions including CO oxidation.