Study on influence factors of chlorpyrifos degradation using TiO2

The influence factors of chlorpyrifos degradation using TiO2 through high-pressure mercury lamp were investigated.Concentrations of chlorpyrifos were determined with HPLC.The results showed that the concentration 50-100 mg/L TiO2 was the optimum.Significant positive correlation was found between lower concentrations 5-20 mg/L of chlorpyrifos and degradation rate,while negative correlation with higher concentrations of 20-80 mg/L.The degradation kinetics of 10 mg/L chlorpyrifos followed the first order reaction.Different pH decreased below pH 7 after photocatlytic reaction,and alkaline conditions chlorpyrifos was favorable to the degradation.