Purification of textile industry wastewaters by electrocatalic oxidation method using inert electrodes

Global climate change and rapid industrialization are causing the demand for water to increase daily. A large portion of industrial wastewater is used in the textile industry and discharged as wastewater. Environmentally friendly physical and chemical treatment methods are prominent in the treatment of these waters. In this study electrochemical treatment methods (ECM) examined, and an electrocatalytic oxidation method based on electrodes made of Ru/Ir/Ti, RuO2/IrO2/TiO2, and high-density graphite is investigated for the removal of highly concentrated dyes from textile wastewater. The textile wastewater examined in this study is characterized by strong color, high organic content, high pH, high permanence, toxicity, and low biodegradability. The dye oxidation process is dependent on the anode material, pH, temperature, as well as the concentration of chloride ions in the solution and the electrolyte concentration (NaCl). When textile wastewater was examined according to these parameters, it was seen that the maximum output value of 87% was reached at a current density of 150 mA/cm2 and a NaCl concentration of 5 g/L. Color removal from wastewater depending on the current density was 92% for RuO2/IrO2/TiO2 and 98% for Ru/Ir/Ti anodes. A maximum dye removal of 90% could be achieved for the graphite electrode. For the COI parameter (graphite electrode), a maximum removal of 77% could be obtained at a current density of 100 mA/cm2 and a solution treatment time of 10 minutes, while the COI removal percentage was 83% for Ru/Ir/Ti and RuO2/IrO2/TiO2 electrodes at the same current density. As a result, in the electrocatalytic oxidation method; Considering the dependence of color removal, COI, and TOC on parameters such as current density and water treatment time, the efficiency of the wastewater treatment process was found to increase in the order Ru/Ir/Ti> RuO2/IrO2/TiO2> graphite. Electrocatalytic oxidation, characterized by low operating costs and low chemical consumption, holds a significant place among treatment methods.