| 水体系中氧氟沙星的光化学降解研究 |
| 摘要点击 2904 全文点击 1587 修订日期：2011-04-26 |
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| 中文关键词 氧氟沙星 光化学降解 海水 光致毒性 动力学 |
| 英文关键词 ofloxacin(OFLX) photochemical degradation seawater phototoxicity kinetics |
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| 中文摘要 |
| 研究了高压汞灯和氙灯照射下氧氟沙星(OFLX)在蒸馏水、人工海水和天然海水中的光降解过程,探讨了光源、起始浓度、丙酮、表面活性剂等因素对 OFLX光化学降解速率的影响.结果表明, OFLX在高压汞灯下的光反应速率比在氙灯下快得多,均符合一级反应动力学过程; 在相同光源下, OFLX在海水中降解最快,其次是人工海水; 当 OFLX初始浓度为 2、4、6 mg·L-1时,其光解速率常数分别为 0.163、0.140和0.132 min-1,随着OFLX初始浓度增大,其光解率降低; 不同浓度的丙酮均能促进 OFLX光降解的反应,其反应速率常数为 0.0842~ 0.102 min-1,且光敏效率与丙酮浓度呈正相关关系; 然而当十六烷基三甲基溴化铵(CTAB)、十二烷基苯磺酸钠(SDBS)、吐温-20(TW-20)等表面活性剂的浓度为 5 mg·L-1,它们均抑制了水体中 OFLX光降解反应的进程.另外,利用金藻 8701单种培养进行了 OFLX光化学降解前后的毒性试验,表明 OFLX光解过程产生风险较高的中间产物,随着光解进行,产物毒性降低. |
| 英文摘要 |
| The photodegradation of ofloxacin (OFLX) was investigated in distilled water, artificial seawater and natural seawater exposed to high-pressure mercury lamp and xeon lamp. The photolysis of OFLX was affected by various factors including light sources, initial concentrations, acetone and surfactants. The photoreaction rate of OFLX under high pressure mercury lamp was much faster than that under xeon lamp, conforming to the first-order kinetics behavior. Expose to the same light intensity, The photodegradation rate of OFLX was the quickest in natural seawater, followed by artificial seawater. The initial concentrations of OFLX were 2, 4 and 6 mg·L-1, the rate constants were 0.163, 0.140 and 0.132 min-1, respectively. The photodegradation rates of OFLX in seawater decreased along with its initial concentration. The addition of acetone could accelerate the photoreactions of OFLX, The constants of the reaction rate range from 0.0842-0.102 min-1. A positive correlation was found between the photosensitive efficiency and the added concentration of acetone. On the contrary, the addition of cetyl trimethyl ammonium bromide(CTAB), sodium dodecyl benzene sulfonate(SDBS) and Tween-20(TW-20) inhibited the photodegradation of OFLX, of which concentrations were all 5 mg·L-1. In addition, toxicity tests with Isochrysis galbana 8701 showed higher risk of intermediate products generated from photolysis of OFLX. The toxicity of products decreased along with the reaction. |
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