UV/H2O2工艺降解环丙沙星的研究

采用UV/H2O2工艺去除水体中的喹诺酮类抗生素环丙沙星（CIP）。考察了溶液pH值、H2O2投加量以及水体基质对环丙沙星降解效率的影响,分析了降解产物的生成情况。研究表明,环丙沙星的降解符合拟一级反应动力学模型。降解速率受溶液pH值的影响,酸性及中性条件,有利于环丙沙星的降解。H2O2投加量的增大,使得降解速率逐渐增大,但速率增幅逐渐变缓;最佳H2O2/环丙沙星摩尔比为2 000。实际水体中存在的NOM、NO3-,促进了单独UV作用下,环丙沙星的降解。水体中的.OH焠灭剂,抑制了UV/H2O2联合作用下,环丙沙星的降解;实际水体中的光解速率常数低于超纯水中的光解速率常数。GC-MS分析表明,UV/H2O2工艺,使环丙沙星氧化降解生成氨基乙酸、丙二酸、丙三醇和对苯二甲酸等小分子有机物。

Degradation of ciprofloxacin by UV/H2O2 process

The degradation of ciprofloxacin in UV/H2O2 process was investigated with a low-pressure UV lamp system.The influence of initial pH values,H2O2 concentration and water quality was discussed;the degradation products of ciprofloxacin were also analyzed.Results show that ciprofloxacin displays a pH-dependent degradation and the neutral condition is more favorable.Reaction rates increased with the increasing of H2O2 concentration,and the optimal H2O2/ciprofloxacin molar ratio at which the highest reaction rate constant is reached is 2 000.In UV direct photolysis,degradation rates of ciprofloxacin in natural water are higher than those in ultrapure water;while in UV/H2O2 process,the degradation rates in natural water are lower than those in ultrapure water.Moreover,several degradation products such as propanedioic acid,glycerin,1,4-benzenedicarboxylic acid,and some aliphatic acids etc.forming in the degradation of ciprofloxacin in UV/H2O2 process are identified by GC-MS.