Study on Degradation of Crystal Violet by UV/Fenton/Heteropolyacid System

摘要

The degradation of an azo dye crystal violet by UV/Fenton oxidation process in the presence of heteropolyacid solution has been investigated. The degradation rate is strongly dependent on the pH, initial concentrations of the dye, Fe~(2+), H_2O_2 and phosphotungstic acid. The effect of these parameters has been studied and the optimal reacting conditions were experimentally determined. It was found to be initial pH 2.7, [H_2O_2]=71 mM, [Fe~(2+)]=0.5 mM, [dye]_0=20 mg/L, phosphotungstic acid concentration is 24 mg/L. Under optimal conditions, 95% degradation efficiency of dye in the presence of heteropolyacid solution was achieved after 60 min of reaction. The experimental results showed that the UV/Fenton oxidation process was an effective process for the degradation of crystal violet at low H_2O_2 and Fe~(2+) concentrations. Meanwhile, this research also proved that heteropolyacid could improve the photocatalytic efficiency in the UV/Fenton reaction as an efficient activator.