Decolorization and degradation of reactive red 120 azo dye by oxidation processes

Abstract

In this study, the treatment of azo dye, Reactive Red 120 (RR120) by oxidation using (ozone) O3 and ozone/hydrogen peroxide (O3/H2O2) treatments were evaluated. O3 carried out using a glass reactor, generated from an ozone generator utilizing pure oxygen. H2O2 was added to the dye samples for O3/H2O2 experiments, just before the gas entered the reactor. Contact time of 1, 2, 3, 4, 5, 10, 15 and 20 min were done to evaluate the performance of O3 and O3/H2O2 treatment process. The drop of pH indicated the formation of acidic by-products. The performance of O3 and O3/H2O2 in the removal of color is 100% after 20 min treatment. O3 appeared more effective than O3/H2O2 treatment process in terms of color and chemical oxygen demand (COD) removal. Color and COD removal increases as the increase of contact time. The FT-IR spectrum of both treatment indicated evidence for the cleavage of the azo dye structure.