催化臭氧程序分解水相有機氯農藥效率之研究

本研究以均質相(Homogeneous phase)之臭氧/紫外光(O_3/UV)及異相(Heterogeneous phase)之臭氧/氧化鋅(O_3/ZnO)、臭氧/氧化鋅/紫外光(O_3/ ZnO/UV)催化臭氧程序(Catalytic ozonation processes)，進行對難分解有機氯農藥(Organochlorine pesticides，OCPs)破壞分解效率之探討，並藉此瞭解催化臭氧程序是否可將有機氯農藥達到完全礦化之目的。結果顯示，O_3/UV及O_3/ZnO/UV兩組催化臭氧程序，對單獨O_3無法氧化之酸性有機氯農藥Dalapon可達90%去除率，然而在分析總有機碳(TOC)的衰減率，發現僅約60%的Dalapon鍵結之有機碳被完全礦化成CO_2，同時在計算液相中Cl-濃度及Dalapon所鍵結的Cl原子，發現僅有約40%之有機氯被氧化釋出氯離子，因此研判O_3/UV或O_3/ZnO/UV在分解Dalapon農藥過程，仍無法完全將其礦化，在反應時間終止後仍存在有機性之中間產物或副產物(By-products)。再者，本研究選擇水體環境中常見的十五種OCPs，以添加至地下水方式進行O_3及O_3/UV氧化效率之探討，結果發現UV催化O_3程序對十五種OCPs之氧化分解效率均較單獨O_3氧化者高，尤其以Aldrin及HCH衍生性農藥較為顯著，因此研判UV對O_3的氧化力確有正面助益。

關鍵字

有機氯農藥；臭氧；紫外光；氧化鋅；催化臭氧程序；得拉本

並列摘要

Catalytic ozonation processes are used as advanced oxidation processes for degradation of the recalcitrant organochlorine pesticides(OCPs). The degradation process of the OCPs, both homogeneous photocatalytic(O_3/UV)and heterogeneous catalytic(O_3/ZnO and O_3/ZnO/UV)ozonation are applied to assess the suitability of these ozonation processes to promote mineralization of recalcitrant OCPs compounds. The best results of chlorinated pesticides degradation are obtained when UV combined with ozone is applied; with the use of this catalytic ozonation process the aqueous pesticides(dalapon)was found to be effective approach 90% removal rate. Moreover, the degradation of the mixed 15 species of OCPs in solution, the application of O_3/UV system lead to a strong pesticides reduction compared to O_3 alone. However, the results of chloride ion produced on degradation of dalapon, only 40% of chloride was broken and released from C-Cl bonding of dalapon. It can be suggested that some of intermediates and by-products were generated during catalytic ozonation processes.

並列關鍵字

organochlorine pesticides ； ozone ； ultraviolet ； zinc oxide ； catalytic ozonation processes ； dalapon

參考文獻

Shukla, G., Kumar, A., Bhanti, M., Joseph, P.E., and Taneja, A. （2006.2）, “Organochlorine pesticide contamination of ground water in the city of Hyderabad”, Environment International, Volume 32, Issue 2: pp244-247

Google Scholar

Yang, R.Q., Lv, A.H., Shi, J.B., and Jiang, G.B.（2005.10）, “The levels and distribution of organochlorine pesticides(OCPs) in sediments from the Haihe River, China” , Chemosphere, Volume 61, Issue 3:pp347-354