Oxidation of Aqueous Cyanide Solution Using Hydrogen Peroxide in the Presence of Heterogeneous Catalyst

Abstract

The oxidation of aqueous cyanide solution using hydrogen peroxide in the presence of heterogeneous catalyst, Ru/MgO, was tested in a batch reactor at room temperature. The cyanide oxidation using hydrogen peroxide was markedly enhanced in the presence of Ru/MgO catalyst with compared to the control, aqueous cyanide solution containing hydrogen peroxide in the absence of the catalyst. The rate of catalytic cyanide oxidation was observed to be function of the reaction conditions such as pH, temperature and H₂O₂/CN ratio. The optimum pH for the catalytic cyanide oxidation was between 6 and 8. The conversion rate of catalytic cyanide oxidation was increased with increasing temperature. H₂O₂/CN ratio was observed to determine the conversion rate. The optimum H₂O₂/CN ratio was between 1.2 and 1.6 at room temperature (18°C).