UV/H_2O_2联用工艺对甲霜灵农药的降解

Degradation of Pesticides Metalaxyl by Combined Processes of UV/H_2O_2

研究了高级氧化联用技术UV/H2O2光激发工艺去除水中甲霜灵的性能。试验结果表明,降解效果明显,其降解曲线呈现拟一级反应动力学的特征。研究了不同的影响因素,诸如不同H2O2的投加量、甲霜灵初始浓度、初始pH和水中常见阴离子等,对UV/H2O2光激发工艺对甲霜灵的降解的影响。在试验H2O2投加量范围内,随着H2O2投加量的增加,甲霜灵的降解速率增加;随着甲霜灵初始浓度的升高,光解反应的初始反应速率也随之增加,拟一级反应速率常数k下降;最佳pH为5;水中常见阴离子对UV/H2O2工艺降解甲霜灵影响的大小顺序为CO2-3>NO-3>SO2-4>Cl-。

Removal performance of pesticide metalaxyl by UV/H2 O2 combined processes was studied in this article. Experimental results show that UV/H2 O2 process is good for the degradation of metalaxyl. Its degradation curves can be described by pseudo first-order kinetics. The influence factors such as the different dosages of H2 O2 ,initial concentrations of metalaxyl,initial pH values and common anions in water were studied. The rate of degradation metalaxyl increases with the increase of dosage of H2 O2 in the test range. The initial reaction rate of optical excitation reaction increases and the pseudo first-order reaction rate constant decreases with the increase of initial concentration of metalaxyl. The best pH value is 7. The sequence of effect of the four inorganic anions on the degradation metalaxyl by UV/H2 O2 process is CO2-3 〉NO3- 〉SO2-4 〉Cl-.