Catalytic Wet Air Oxidation of Oxalic Acid using Platinum Catalysts in Bubble Column Reactor: A Review

Wastewater treatment and re-use of industrial process water are critical issue for the development of human activities and environment conservation. Catalytic wet air oxidation (CWAO) is an attractive and useful technique for treatment of effluents where the concentrations of organic pollutants are too low, for the incineration and other pollution control techniques to be economically feasible and when biological treatments are ineffective, e.g. in the case of toxic effluents. In CWAO, combustion takes place on a Pt/Al2O3 catalysts usually at temperatures several degrees below those required for thermal incineration. In CWAO process, the organic contaminants dissolved in water are either partially degraded by means of an oxidizing agent into biodegradable intermediates or mineralized into innocuous inorganic compounds such as CO2, H2O and inorganic salts, which remain in the aqueous phase. In contrast to other thermal processes CWAO produces no NOx, SO2, HCl, dioxins, furans, fly ash, etc. This review paper presents the application of platinum catalysts in bubble column reactor for CWAO of oxalic acid.