Removal of H2S and COD Using UV, Ferrate and UV/Ferrate from Municipal Wastewater

Background; The aim of this study is to compare UV, ferrate (VI) and UV/ferrate (VI) methods for removal of hydrogen sulfide and chemical oxygen demand (COD) from municipal wastewater under a continuous condition. Methods; The experiment was divided into three parts: 1) pollutants removal by using ferrate (VI) alone; 2) pollutants removal using UV alone; 3) pollutants removal using a combination of UV/ferrate (VI). The electrolysis process was utilized to generate ferrate (VI). Results;The results showed that UV had the highest pollutants removal, so that 89% and 85% of hydrogen sulfide and COD were removed from the wastewater, respectively. UV/ferrate (VI) ranked as the next most efficient method. This method removed 65% and 73% of hydrogen sulfide and COD, respectively from the wastewater. Conclusion; Using ferrate (VI) alone had the lowest pollutant removal efficiency, with 41% and 48% of hydrogen sulfide and COD removal from wastewater, respectively. UV has a higher ability to remove hydrogen sulfide and COD from wastewater, compared with UV/ferrate (VI) and ferrate (VI) alone.