Reactor Technology for Aqueous Phase Catalytic Oxidation of Organics

An investigation of the efficacy of low temperature aqueous phase catalytic oxidation for the destruction of organic water pollutants of significance to the U.S. Armed Forces is proposed. It has been shown in our laboratory that organic contaminants can be mineralized in the aqueous phase using dioxygen over noble metal catalysts at temperatures between 120-160C. Work to date has been an outgrowth of regenerative life support research for manned space exploration. Contaminants studied have been those typical of hygiene wastepaper, humidity condensates, and urine distillates. Organics occurring in highest quantity in these streams are low molecular weight alcohols, carboxylic acids, and urea. Experimental results have indicated deep oxidation of mixed contaminant streams containing dissolved organic compounds at concentrations between 10-200 mg/L. Studies comparing this technique with other methods of organic contaminant reduction such as photocatalysis, UV oxidation, and photoelectric oxidation have shown heterogeneous catalysis to be vastly more effective in terms of reactor size and residence time requirements. Extension of this technique to organics commonly polluting ground and surface waters is proposed. Contaminants studies will include trichlorethylene (TCE), 2,4-dinitrophenol (DNP), JP-4, and decachlorobiphenyl (a PCB).