Shemer Hilla, Linden Karl G
Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708.
J Photochem Photobiol A Chem. 2007 Apr 15;187(2-3):186-195. doi: 10.1016/j.jphotochem.2006.10.018.
Photodegradation of a mixture of three polycyclic aromatic hydrocarbons fluorene (FLU), dibenzofuran (DBF), and dibenzothiophene (DBT) using UV and UV/HO processes was studied. Treating a mixture of the PAHs stimulated a more realistic contamination composition present in polluted water. Effects of pH, PAH concentration, and water matrix composition on removal rates and efficiencies of these compounds are discussed. Batch experiments were conducted using both monochromatic low pressure (LP, 253.7 nm) and polychromatic medium pressure (MP, 200-400 nm) UV sources, in a quasi-collimated beam setup. A synergistic effect was observed during direct photolysis and LP-UV/HO of the mixture as compared to photodegradation as a single component in an aqueous solution. Similar results were obtained for FLU using MP-UV/HO whereas, degradation of DBF and DBT was inhibited in a mixture. Natural water enhanced the direct photolysis compared to laboratory buffered water, whereas, degradation of the PAHs in the natural water was inhibited using UV/HO process. Toxicity testing using a luminescent inhibition bioassay was correlated to intermediates generated during UV-based oxidation reactions.
研究了使用紫外线（UV）和UV/羟基自由基（UV/HO）工艺对芴（FLU）、二苯并呋喃（DBF）和二苯并噻吩（DBT）三种多环芳烃混合物的光降解情况。处理多环芳烃混合物模拟了污染水中更实际的污染物组成。讨论了pH值、多环芳烃浓度和水基质组成对这些化合物去除率和效率的影响。在准直光束装置中，使用单色低压（LP，253.7 nm）和多色中压（MP，200 - 400 nm）紫外线源进行了批量实验。与在水溶液中作为单一成分的光降解相比，在混合物的直接光解和LP-UV/HO过程中观察到了协同效应。使用MP-UV/HO对芴得到了类似的结果，而在混合物中DBF和DBT的降解受到抑制。与实验室缓冲水相比，天然水增强了直接光解，而在UV/HO工艺中天然水中多环芳烃的降解受到抑制。使用发光抑制生物测定法进行的毒性测试与基于紫外线的氧化反应过程中产生的中间体相关。
