Degradation of azo dye Amido black 10B in aqueous solution by Fenton oxidation process

Abstract

The degradation of an azo dye Amido black 10B in aqueous solution by Fenton oxidation process has been investigated. The effects of different reaction parameters such as initial pH, the initial hydrogen peroxide concentration ([H 2O 2] 0), the initial ferrous concentration ([Fe 2+] 0), the initial Amido black 10B concentration ([dye] 0) and the temperature on the oxidative degradation of Amido black 10B have been assessed. The optimal reacting conditions were experimentally determined and it was found to be initial pH = 3.50, [H 2O 2] 0 = 0.50 mM, [Fe 2+] 0 = 0.025 mM for [dye] 0 = 50 mg/L at temperature = 25 °C. Under optimal conditions, 99.25% degradation efficiency of dye in aqueous solution was achieved after 60 min of reaction. The UV–vis spectral changes of Amido black 10B in aqueous solution during Fenton treatment process were studied. It was easier to destruct the azo linkage (–N N–) group than to destruct the aromatic rings of Amido black 10B by Fenton oxidation. The experimental results showed that the Fenton oxidation process was an effective process for the degradation of azo dye Amido black 10B at low H 2O 2 and Fe 2+ concentrations.