A Comparative Study among the Technology Classic Fenton and Electro-Fenton for the Degradation of Polyvinyl Alcohol in Textile Industrial Wastewater

Abstract

Wastewater containing high concentrations of polyvinyl alcohol (PVA) resists conventional methods such as biological oxidation and requires high doses of chemicals in the case of chemical processes such as coagulation and adsorption. Due to these features, a comparative study has been conducted for the treatment of PVA in textile industrial wastewater by classic Fenton (CF) and electro-Fenton (EF). According to the results of CF, the optimum removal efficiency of the total organic carbon was obtained as 81% at pH 3.0, 43.5 g/L of H₂O₂ dose, 2.5 g/L of FeSO₄·7H₂O during 24 h and it reached 85.5% at 120 min in EF at the optimum values (pH 3, H₂O₂ dose = 43.5 g/L and 0.58 A of the current). When the cost of treatment by the CF method was found as 78.206 €/m³, it was 78.046 €/m³ by the EF process. For the first time in the literature, a comparative study of EF and CF in treatment of the PVA-containing wastewater was presented and high treatment efficiency was achieved. In this study, pH change in the EF process and its negative effects on the treatment efficiency were observed. Determining the need for constant pH adjustment to eliminate these negative effects is one of the most important outputs of this study. In addition, higher treatment efficiencies by EF have been obtained compared to CF.