UV-TiO_2光催化氧化降解双酚A的动力学研究

摘要

采用自制光催化氧化反应器,研究了双酚A(BPA)在纳米TiO_2悬浆体系中的光催化氧化特性.结果表明:(1)UV-TiO_2对水中BPA有较强光催化氧化降解作用.在10 W低压汞灯照射下,当纳米TiO_2用量为1.0 g/L、pH为5.5、BPA初始质量浓度为10 mg/L、曝气量为4.0 mL/min、温度为室温、反应时间为120 min时,BPA去除率可达97.1%.当pH≥9.5时,120 min后BPA已经基本光催化氧化降解完全.(2)BPA的光催化氧化降解曲线均很好地符合一级反应动力学方程.其速率常数与纳米TiO_2用量、pH、BPA初始浓度、曝气量有关;促进·OH和电子-空穴对的生成是提高光催化氧化反应速率的重要途径.%Photocatalytic degradation of bisphenol A (BPA) in aqueous solution with UV as induced light by nano TiO_2 suspended system was studied in home-made batch photo-reactor. Effects of pH ,initial BPA concentration, TiO_2 dosage and aeration rate on photocatalytic process were investigated respectively. The results showed that the UV/TiO_2 photocatalytic presented perfect BPA degradation effectively,and the process of BPA photodegradation fol-lowed first-order kinetics. With the conditions of TiO_2 dosage= 1.0 mg/L,pH of 5.5,aeration rate of 4.0 mL/min,initial BPA concentration of 10 mg/L and irradiated by 10 W low-pressured mercury vapor discharge lamp,97.1% of BPA was degraded in 120 rain. And BPA was almost completely removed in 120 rain when phi>9.5. The photodeg-radation rate constant of BPA was strongly related to the above influence factors.