Effect of wastewater quality parameters on oxidation by tin oxide anodes

The use of tin oxide anodes (TOAs) has been proposed for the disinfection of wastewater effluents and concurrent treatment of emerging contaminants. The common water quality constituents suspended solids, chemical oxygen demand (COD), alkalinity, ammonia-nitrogen, nitrite-nitrogen, and nitrate-nitrogen were investigated for their effect on oxidation performance by TOAs. Relative oxidant generation rates were not affected by increasing concentrations of suspended solids, COD, alkalinity, ammonia-nitrogen, or nitrate-nitrogen. Although nitrite-nitrogen did compete for oxidants generated by TOAs, nitrite is not usually present in oxygenated effluents. Chemical oxygen demand, ammonia, and nitrite were oxidized in the TOA systems, primarily through a non-hydroxyl radical mechanism. This research demonstrates that a majority of the common water quality constituents did not negatively affect TOA oxidation performance. Tin oxide anodes represent a potentially low cost and low maintenance option for single-step disinfection and treatment of emerging contaminants in wastewater effluents.