Effect of ultraviolet and visible lights on degradation of congo red dye using Fe2+/H2O2

Abstract

Congo Red is one of the reactive dyes that often used in the textile industry. The presence of Congo red dyes in the environment can damage various living species because of high toxicity. One alternative method to degrade the Congo red is Fenton Reagent. Fenton reagent is defined as a mixture of H2O2 and Fe2+. The Fenton reagent produces a hydroxyl radical (HO •), which degrades Congo red dyes under light irradiation; this reaction is called the Photo-Fenton reaction. The purpose of this research is to determine the effect of visible and ultraviolet irradiation on Congo Red degradation using the Fe2+/H2O2. The results showed that the optimum condition of degradation achieved at 350 ppm, 400 ppm for H2O2 and FeSO4.7H2O concentration, respectively, and pH 3. The kinetics analysis showed that the Congo Red degradation followed the pseudo-first-order kinetics, and Congo Red degradation under UV light showed the highest rate constant.