Mechanism of Acid Red G Degradation by VUV-activated Chlorite
The oxidative degradation mechanism of azo dye acid red G by vacuum ultraviolet(VUV)activa-ted chlorite(ClO2-)was studied,and the effects of different systems,ClO2-concentration,initial pH value,ini-tial concentration of acid red G,inorganic anions,printing and dyeing auxiliaries on the degradation efficiency of acid red G were explored.The results showed that when the initial mass concentration of acid red G was 50 mg/L,the concentration of ClO2-was 0.4 mmol/L and the reaction time was 10 min,the removal rate of acid red G in VUV/ClO2-system could reach 98.3%.The removal rate of ARG decreased with the increase of pH value.Cl-promoted the oxidative decomposition of ARG.HCO3-had a weak inhibitory effect,while NO3-and SO42-had a minor impact.Sodium citrate and SDBS had a significant inhibitory effect.The main oxidizing sub-stances in VUV/ClO2-system were·OH,1O2,Cl·and ClO·.The mechanism of ARG degradation was the fracture of azo bond and the destruction of naphthalene ring.
Acidic red GVUVChloriteActive radicalOxidation degradation