Degradation of octylphenol and nonylphenol by ozone - part II: indirect reaction.
Degradation of octylphenol and nonylphenol by ozone - part II: indirect reaction.
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DOI：
10.1016/j.chemosphere.2007.01.055
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发表时间：
2007-06
期刊：
影响因子：
8.8
通讯作者：
B. Ning;N. Graham;Yanping Zhang
中科院分区：
文献类型：
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作者：
B. Ning;N. Graham;Yanping Zhang
研究了臭氧与辛基酚(OP)和壬基酚(NP)这两种烷基酚(AP)的水溶液反应。这两种化合物都是重要的内分泌干扰化学品，源于烷基酚聚氧乙烯醚的生物降解，通常在废水流出物中发现相对较高的浓度。本文给出了分子臭氧与未解离的OP和NP之间的反应速率常数，以及在pH值为7-9范围内两种AP降解的总反应速率常数。分子臭氧降解OP和NP的动力学速率常数分别为4.33(±0.18)×104和3.90(±0.10)×104M−1s−1，两种情况下的反应化学计量比相似，约为1.3：1([O_3]：[AP])。两个AP的总二级反应速率常数随着pH的增加而显著增加，这被认为主要是由于间接自由基反应的影响随着pH的增加而增加；这一方面在配套论文中有更详细的考虑。对反应机理的初步研究表明，臭氧氧化的初始产物是羟基烷基苯酚。
This aqueous reaction between ozone and two alkylphenols (APs), namely octylphenol (OP) and nonylphenol (NP), has been investigated. Both compounds are important endocrine disrupting chemicals, which arise from the biodegradation of alkylphenol ethoxylates and are often found at relatively high concentrations in wastewater effluents. In this paper the results of an experimental study are presented which provide values for the reaction rate constants between molecular ozone and undissociated OP and NP, and overall reaction rate constants for the degradation of the two APs at pH values in the range of 7–9. The kinetic rate constants for OP and NP degradation by molecular ozone were 4.33(±0.18)×104and 3.90(±0.10)×104M−1s−1, and the reaction stoichiometry was similar in both cases and equal to approximately 1.3:1 ([O3]:[AP]). The overall second order reaction rate constants for the two APs increased significantly with increasing pH, which is believed to be mainly due to the increasing influence of indirect radical reaction with increasing pH; this aspect is considered in more detail in a companion paper. A preliminary investigation of the reaction mechanism suggests that an initial product of ozonation is hydroxyl-alkyl phenol.