海水中二苯并噻吩的光化学氧化动力学研究

Kinetic Study on Photochemical Oxidation of Dibenzothiophene in Seawater

实验研究天然海水中二苯并噻吩的光化学氧化的动力学。结果发现，二苯并噻吩光化学氧化的速率会受到介质、光敏剂、重金属离子以及辐射强度的影响。其一级反应速率常数为３．９×１０－６～１．８×１０－５ｓ－１。Ｃｕ２＋和Ｈｇ２＋能明显加快二苯并噻吩的光氧化速率。光源离反应容器越近，其降解速率越大。溶解氧的含量越低，二苯并噻吩的光降解速率越慢，这说明溶解氧参与了二苯并噻吩的光氧化过程。由此证实，光化学过程是二苯并噻吩在海水中迁移变化的重要途径。

A kinetic study on the photochemical oxidation of dibenzothiophene in seawater was conducted. The photo oxidation rates of dibenzothiophene were affected by the medium, photosensitizer, heavy metal ions, and irradiation intensity. The first order rate constants of dibenzothiophene photo oxidation ranged from 3.9×10 -6 to 1.8×10 -5 s -1 . The addition of Cu 2+ or Hg 2+ into seawater could markedly increase the photo oxidation rate of dibenzothiophene. It was also found that the photo oxidation rate of dibenzothiophene increased with decreasing distance between the high pressure mercury lamp and the reaction vessel. In addition, the photo oxidation rate of dibenzothiophene decreased with decreasing dissolved oxygen content, indicating that dissolved oxygen participated in the process of dibenzothiophene photo oxidation. Thus it can be seen that photochemical process is an important pathway to remove dibenzothiophene from seawater.