Insights into the differences in metal anchoring mechanisms and the impact on HCN catalytic oxidation performance

Hydrogen cyanide (HCN) is often produced in various industrial processes, such as metal smelting, carbon fiber production, etc. Due to its highly toxic nature, it has significant harm to the human body and the environment. Catalytic oxidation can convert HCN into non-toxic N2, CO2 and H2O. In this study, we conducted a comparative evaluation of the catalytic oxidation of HCN using Cu, Co and Mn as catalyst active centers, and used in situ DRIFTS to explore the reaction mechanism of HCN catalytic oxidation. The difference in the anchoring state of different metals on the hydroxyl groups on the Al2O3 surface, mainly the difference in anchoring strength and hydroxyl consumption, determines the difference in the metal dispersion state, which in turn affects the oxygen activation ability and HCN oxidation performance. Under high loading conditions, compared to Co and Mn, Cu species are more fully anchored due to lower hydroxyl consumption, exhibiting higher dispersion and redox properties, so the 10Cu/Al2O3 catalyst performs well HCN oxidation activity.