Co^(2＋)催化超声/H2O2降解环丙沙星

Degradation of ciprofloxacin aqueous solution by combined Co^(2+) and US/H_2O_2 system

论文研究过渡金属离子Co^(2+)对超声/H_2O_2(US/H_2O_2)降解环丙沙星的催化效果,考察了Co^(2+)、H_2O_2添加浓度、反应温度及初始pH值等主要因素的影响。结果表明,Co^(2+)能够有效催化超声/H_2O_2体系降解环丙沙星,降解过程符合假一级反应动力学。H_2O_2浓度在4.0~32.0mmol/L,Co^(2+)浓度在25.8~96.8mmol/L范围,环丙沙星的降解率随H_2O_2和Co^(2+)添加浓度的增加而升高;温度对环丙沙星的降解影响较大,15℃~45℃范围,降解率随温度的升高而升高;初始pH值为3.0时环丙沙星的降解率最高。异丙醇的抑制实验表明,Co^(2+)增强环丙沙星超声降解主要在于·OH的氧化作用。HPLC谱图表明,环丙沙星在Co^(2+)/US/H_2O_2降解体系中主要生成三种产物,推断其通过两种途径进行降解。

The aim of this study was to determine the effectiveness of catalysis of Co2＋ based onUS/ H2O2 system to remove ciprofloxacin. Some main influenceing factors such as Co2＋ , H20 2concentration, reaction temperature and initial pH were investigated. Results showed that,Co2＋had a significant synergetic effect on oxidation of ciprofloxacin,which is followed pseudo-first orderkinetics. The degradation rate of ciprofloxacin increased with the increase of H2O2 and Co2＋concentration within the 4.0-32.0 mmol/L and 25. 8 ？96. 8 mmol/L range respectively; thedegradation rate of target compound increased with the reaction temperature heating up at 15 ℃ -45℃ ; When the initial pH value is 3.0, the best catalytic effect of ciprofloxacin was gained. Inhibitionexperiments indicating that the degradation of ciprofloxacin by Co^2＋ catalyze was mainlyoxidizing by · OH. According to HPLC spectrum, three kinds of products are mainly generatedin the process of Co^2＋ /US/ H20 2 degradation of ciprofloxacin,which was identified through two ways.