化学学报 ›› 2004, Vol. 62 ›› Issue (2): 142-147. 上一篇    下一篇

研究论文

微囊藻毒素在单波长紫外光照射下的光降解动态研究

陈伟, 甘南琴, 宋立荣   

  1. 中国科学院水生生物研究所, 武汉, 430072
  • 投稿日期:2003-03-13 修回日期:2003-07-14 发布日期:2014-01-26
  • 通讯作者: 宋立荣,E-mail:lrsong@ihb.ac.cn E-mail:lrsong@ihb.ac.cn
  • 基金资助:
    中国科学院知识创新工程重要项目(No.KSCX2-1-10)国家重点基础研究发展规划项目(No.2002CB412300),国家高技术发展计划863计划(No.2001AA641030)和中国科学院水生生物研究所创新领域前沿资助项目.

Photodegradation Dynamics of Pure Microcystin Variants with Illumination of Fixed Wavelength UV-lights

CHEN Wei, GAN Nan-Qin, SONG Li-Rong   

  1. Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072
  • Received:2003-03-13 Revised:2003-07-14 Published:2014-01-26

研究了两种微囊藻毒素在两种紫外光照射下的光降解行为,研究结果表明:UV-C是降解微囊藻毒素较好的光源;光照强度是影响毒素降解重要的因素,其次是温度和酸度;在UV-C的照射下,水体腐殖质对光降解具有抑制作用;微囊藻毒素的光解反应符合准一级动力学模型.同时本工作还按实际环境水体中毒素的含量水平进行了模拟研究,发现紫外光UV-C对环境水体中低含量的微囊藻毒素具有很强的去除能力.为今后发展无毒、高效、经济实用的饮用水处理技术做了有益的探索.

关键词: 微囊藻毒素, 光降解, 腐殖酸, 动力学, 异构化, 紫外光照射

Photolysis of microcystins by UV irradiation and the effects of different environmental factors on efficiency of UV degradation were studied. The results indicated that the rates of the photolytical degradation reactions of microcystin LR and RR follow pseudo first order kinetic process. The results also showed that the concentrations of two microcystin variants decreased significantly by UV-C irradiation; the wavelength and intensitiy of UV irradiation are two very important factors affecting the rate of degradation; temperature and pH value could also affect the half life of degradation rates. When irradiated by weaker UV light, isomerization could be detected in the course of photolytical degradation. The concentrations of two isomers transformed from microcystin LR reached its maximum at the third minute and decreased with the time afterwards. To simulate photolysis of microcystins in the field water body, microcystins with low concentration were used. It was found that UV-C illumination was capable of decomposing over 95% of microcystins within 40 min. In the presence of humic substances the photodecomposition slowed down to a certain extent. These results are valuable in using UV irradiation for elimination microcystins from raw water.

Key words: microcystin, photodegradation, humic acid, kinetic, isomerization, UV irradiation