2-氯酚水溶液的氧化降解的机理研究  

Mechanism Study on the Oxidizing Degradation of 2-chlorophenol Aqueous Solution

作　　者：刘士姮[1] 汪世龙[1] 孙晓宇[1] 李文哲[1] 朱大章[1] 刘俊英[1] 郑广宏[1] 倪亚明[1] 王文峰[2] 王敏[2] 姚思德[2] 

机构地区：[1]同济大学污染控制与资源化国家重点实验室,上海200092 [2]中国科学院上海原子核研究所辐射化学开放研究实验室,上海201800

出　　处：《科学技术与工程》2003年第2期129-132,共4页Science Technology and Engineering

基　　金：国家自然科学基金(20077019)

摘　　要：利用脉冲辐解技术对2-氯酚稀水溶液在多种条件下的脉冲辐解进行了详细研究。对瞬态光谱中的主要吸收作了归属,并初步考察了这些瞬态粒子的生长、衰减动力学。实验表明2-氯酚与·OH的反应符合假一级动力学,2-氯酚与·OH自由基的反应途径与pH值有关:在中性条件下·OH与2-氯酚主要生成较为稳定的羟基加成物;在酸性条件下,同时生成了羟基加成物和氢加成物,且羟基加成物可发生H^+催化的脱H_2O反应,生成氯酚氧基;在碱性条件,2-氯酚阴离子的羟基加成物不稳定,可进一步脱HCI和OH-而生成氯代酚氧基阴离子和半醌自由基阴离子,同时2-氯酚阴离子与·OH还可直接发生电子转移,形成氯代酚氧基阴离子。The reaction between OH radicals and 2-chlorophenol in dilute aqueous solutions under different conditions wasstudied by pulse-radiolysis tecnology. The main characteristic peaks in the transient absorption spectra were attributed and thebuild-up/decay trends of several transient species were investigated. The reaction of 2-chlorophenol with·OH radicals followspseudo-first order kinetics and the reaction paths are pH dependent. Under neutral condition,·OH radicals are mainly addedto the benzyl ring to form relatively stable hexadienyl type OH-adducts. Under acidic condition, both OH-adducts and H-adducts are formed and OH-adducts can undergo H^(+) induced H_2O elimination. Under alkaline condition, chlorophenoxyl radi-cals and semiquinone radical anions can be formed through OH-addition followed by HCl/OH-elimination. In addition, 2-chlorophenoxyl radicals can also be formed through the electron transfer from 2-chlorophenol anion to ·OH.

关 键 词：2-氯酚 脉冲辐解 瞬态吸收谱 自由基 

分 类 号：O625.23[理学—有机化学]