DEGRADATION OF PHENOL IN WASTEWATER VIA ULTRAVIOLET IRRADIATION ACTIVATED PERSULFATE RADICAL

Abstract

The aim of this study is to investigate the treatment of Phenol in wastewater via persulfate radicals activated by ultraviolet (UV) irradiation, with the objective of evaluating the applicability of the method for wastewater treatment and also defining the key parameters influencing the process. The advantage of the process includes utilizing UV energy to activate persulfate radicals, generating highly oxidative sulfate radicals (SO₄^▪−) with a high oxidation potential of 2.6 eV, capable of non-selectively degrading organic pollutants in water through the breakdown of chemical bonds, transforming them into non-toxic or less harmful products.

To assess the capability of phenol elimination, the degradation efficiency was recorded, and the rate constants under different operating conditions were calculated using the pseudo-first-order kinetic model. The results confirm the feasibility and suitability of this method for decomposing phenol in water with the high degradation efficiency of 99.2% at the concentration of 40 mg/L. The study also revealed factors that affect the phenol degradation performance, including the concentration of Na₂S₂O₈, pH value of the solution, and initial concentration of phenol. Particularly, the degradation efficiency of phenol increased the rise of Na₂S₂O₈ concentration, while, the initial concentration of phenol significantly influenced both efficiency and treatment time. The pH of solution range from acidic to neutral was found to be more favorable for converting persulfate into SO₄^▪− radicals, thereby enhancing the phenol degradation process.