Response surface optimization of the photocatalytic decolorization of a simulated dyestuff effluent

The experimental design methodology was applied for response surface modeling and optimization of the photocatalytic decolorization of a simulated dyestuff effluent (SDE), containing the azo dye Reactive Black 5 (RB5) as colorant. The variables considered were the initial concentration of TiO2, Fe(3+) and H2O2. The multivariate experimental design allowed developing a quadratic model as a functional relationship between color removal efficiency and the independent variables. Under the optimum conditions established, the performance of 99.3% for color removal was experimentally reached. It was found that all factors considered have an important effect in the degradation efficiency of the organic matter.