Sustainable replacement of EDTA–Biojarosite for commercial iron in the Fenton's and UV–Fenton's degradation of Rhowedamine B – a process optimization using Box–Behnken method

Biojarosite as a replacement for commercial iron catalyst in the oxidative degradation of the dye Rhodamine B was confirmed and established. Investigations on the oxidative degradation by Fenton's oxidation and UV–Fenton's oxidation with EDTA at neutral pH were conducted and degradation of target compound was evaluated. UV–Fenton's oxidation was shown to be efficient over Fenton's oxidation in the degradation of Rhodamine B with removal efficiency of 90.0%. Design of Experiments was performed with Box–Behnken design. Investigation was conducted for the predicted values separately for both Fenton's oxidation and UV–Fenton's oxidation and the Rhodamine B removal was taken as response. Variable parameters biojarosite, H2O2 dosage and EDTA were optimized in the range of 0.1–1 g/L, 2.94–29.4 mM and 10–100 mM, respectively. A quadratic regression model is fitted for both Fenton's and UV–Fenton's oxidation. Analysis of variance (ANOVA) is performed and model fit is discussed.