LAUSR

In this study, a correlation of kinetic parameters was established for the decolorization of a methyl orange (MO) azo dye by Fenton oxidation. The experiments were carried out in a batch reactor at room temperature and the operating conditions were optimized using the 2 4−1 fractional factorial design. Each of the selected factors, i.e. the initial concentration of the MO dye, the catalyst dosage (Fe 2+ ), the initial concentration of H 2 O 2 and the pH of the solution, were varied on two levels. Regressions equations were constructed by relating the parameters of dye oxidation rate in aqueous phase (the initial rate V i , the rate constant k and the maximum yield by unit time) to four operating conditions. MO dye decolorization profiles as a function of time were satisfactorily adjusted for the majority of the experiments by second-order kinetics on the Levenberg Marquart algorithm using Minitab 17. The validation of the model equations, carried out by the Analysis of Variance (ANOVA), showed that these equations explain about 98% of the variability of the responses and that these simple linear models should cover 92% of the future responses. It has been shown that there is robust relationship between the dynamic behaviour of this process at the initial time and the maximum yield of decolorization at steady state with dye concentration and hydrogen peroxide.