Dyes Color Removal by Ozone and Hydrogen Peroxide: Some Aspects and Problems

Application of oxidation processes with the use of strong oxidizing agents, ozone and hydrogen peroxide, is limited because of high costs and some problems with parameters of discoloration reactions. This paper presents findings concerning the use of ozone itself and hydrogen peroxide in combination with Fe2+ catalyst for discoloration of dye solutions of concentration 100 mg/L and wastewaters from production of dyestuffs Reactive Orange 20, Reactive Blue 13, Direct Blue 74, and Acid Violet 1. Both agents discolored both the dye solutions and wastewaters successfully. The paper presents a discussion about some aspects and problems occurring in the use of those oxidative agents for discoloration processes in laboratories. There is also a presentation of the effects that such parameters as consumption of oxidants and the doses applied, pH and temperature, had on the time required for discoloration reactions.