Rao Y F, Chu W
Department of Civil and Structural Engineering, Research Centre for Urban Environmental Technology and Management, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Chemosphere. 2009 Mar;74(11):1444-9. doi: 10.1016/j.chemosphere.2008.12.012. Epub 2009 Jan 21.
The degradation of linuron, one of phenylurea herbicides, was investigated for its reaction kinetics by different treatment processes including ultraviolet irradiation (UV), ozonation (O3), and UV/O3. The decay rate of linuron by UV/O3 process was found to be around 3.5 times and 2.5 times faster than sole-UV and ozone-alone, respectively. Experimental results also indicate overall rate constants increased exponentially with pH above 9.0 while the increase of rate constants with pH below 9 is insignificant in O3 system. All dominant parameters involved in the three processes were determined in the assistant of proposed linear models in this study. The approach was found useful in predicting the process performances through the quantification of quantum yield (Phi(LNR)) (rate constant for the formation of free radical HOO(.-) from ozone decomposition at high pH), rate constant of linuron with ozone ((k(O3,LNR)), rate constant of linuron with hydroxyl radical (k(OH,LNR)), and alpha (the ratio of the production rate of OH() and the decay rate of ozone in UV/O3 system).
对苯脲类除草剂利谷隆的降解进行了研究，通过紫外线照射（UV）、臭氧化（O3）和UV/O3等不同处理工艺考察其反应动力学。结果发现，利谷隆在UV/O3工艺下的降解速率分别比单独的UV和单独的臭氧快约3.5倍和2.5倍。实验结果还表明，在O3体系中，pH高于9.0时总速率常数呈指数增加，而pH低于9时速率常数的增加不显著。本研究通过所提出的线性模型确定了这三种工艺中所有主要参数。该方法通过量化量子产率（Phi(LNR)）（高pH下臭氧分解产生自由基HOO(.-)的速率常数）、利谷隆与臭氧的反应速率常数（(k(O3,LNR))）、利谷隆与羟基自由基的反应速率常数（k(OH,LNR)）以及α（UV/O3体系中OH(.)的生成速率与臭氧衰减速率之比），被发现可用于预测工艺性能。
