The intermediate products in the degradation of 4-chlorophenol by pulsed high voltage discharge in water
The intermediate products in the degradation of 4-chlorophenol by pulsed high voltage discharge in water
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水中脉冲高压放电降解4-氯苯酚的中间产物
DOI：
10.1016/j.jhazmat.2011.06.045
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发表时间：
2011-09-15
影响因子：
13.6
通讯作者：
Chen, Xihua
中科院分区：
文献类型：
--
作者：
Bian, Wenjuan;Song, Xuehong;Chen, Xihua
脉冲高压放电降解对氯苯酚是一个复杂的过程，涉及一系列复杂的化学反应。4-氯苯酚羟基化生成对苯二酚、4-氯间苯二酚和4-氯邻苯二酚是第一步，但观察到很少量的C-1-C-2或C-5-C-6键的直接裂解产物。4-氯邻苯二酚的产率约为对苯二酚的两倍。产生的4-氯间苯二酚较少。4-氯苯酚降解掉的游离氯离子可以从放电中重新获得反应性，并与未降解的4-氯苯酚反应生成2，4-二氯苯酚。还鉴定了一些开环产物，并提出了它们可能的反应路线。有几种化合物用正品进行了验证。更稳定的开环产品是低分子量(LMW)酸，如甲酸、醋酸、草酸、丙二酸、马来酸和苹果酸。在4-氯苯酚水溶液中放电36min，降解后的碳中有机酸碳量大于50%，芳香烃碳量小于20%，约占初始碳量的94%。放电60min后，4-氯苯酚及其芳香族中间体全部被完全去除，有机碳主要以乙酸、草酸等有机酸形式存在。在120min放电结束时，剩余有机碳量不超过初始碳的14%。(C)2011爱思唯尔B.V.保留所有权利。
Degradation of 4-chlorophenol by pulsed high voltage discharge is an intricate process involving a series of complex chemical reactions. Hydroxylation of 4-chlorophenol to form hydroquinone, 4-chlororesorcinol and 4-chlorocatechol is the first step, though a very small amount of direct cleavage products of the C-1-C-2 or C-5-C-6 bond are observed. The yield of 4-chlorocatechol is about twice as much as that of hydroquinone. Less 4-chloresorcinol is produced. The free chloride ions dropped from the 4-chlorophenol degradation can obtain reactivity again from the discharge, and react with undegraded 4-chlorophenol to form 2,4-dichlorophenol. Some ring-opened products have also been identified and their possible reaction routes are proposed. Several compounds are verified by use of authentic samples. The more stable ring-opened products are low molecular weight (LMW) acids such as formic, acetic, oxalic, malonate, maleic and malic acid. By discharging 4-chlorophenol aqueous solution for 36 min, the amount of carbons obtained from organic acids is more than 50% while that of carbons from aromatic products less than 20% in the carbons of degraded 4-chlorophenol, which is about 94% of initial carbons. After 60 min of discharge, all the 4-chlorophenol and its aromatic intermediates have been removed completely and the organic carbons are mainly presented as organic acid such as acetic and oxalate acid. At the end of the 120 min discharge, the amount of the remaining organic carbons is not more than 14% of the initial carbons. (C) 2011 Elsevier B.V. All rights reserved.