Application of Central Composite Design to the Photo Fenton Degradation of Methyl Orange Azo Dye Using Fe-Activated Carbon Catalyst

Abstract

Photo-fenton oxidation technique is one of the emerging oxidation processes explored in treatment of organic pollutants in aqueous solutions. This research is focused on utilization of Fe(II) loaded activated carbon and H2O2(aq) in a photofenton process to generate hydroxyl radicals that mineralize methyl orange dyes. Samples of activated carbon were treated with Fe(NO3)2(aq) and characterized using SEM, pHZPC, specific surface area and boehm’s titration. The degradation of methyl orange by the iron loaded activated carbon (Fe-Ac), via photo-Fenton process, was investigated in lab-scale defined by experimental design. Central composite design (CCD) was used to evaluate the effects of the five independent variables considered for the optimization of the oxidative process: time, FeAc dose, methyl orange concentration, pH and H2O2 concentrations. In the optimization, the correlation coefficients (R2 ) for the quadratic model was 0.9941. Optimum reaction conditions were obtained at pH = 3, catalyst dose = 0.1 mg/100ml, H2O2 = 0.62ml, methyl orange concentration = 5mg/l and time = 30 minutes.