UV/(亚)硝酸盐体系氯代硝基物降解及机理研究  

Degradation and transformation mechanism of chlorinated nitroaromatic compounds within UV/NO_2^-/NO_3^- system

作　　者：周骏 闫国杰 施曙东 王琦 李文超 石寒松 ZHOU Jun;YAN Guo-jie;SHI Shu-dong;WANG Qi;LI Wen-chao;SHI Han-song(Shanghai Pudong Road & Bridge Construction Coration, Limited, Shanghai 201210, China)

机构地区：[1]上海浦东路桥建设股份有限公司,上海201210

出　　处：《中国环境科学》2017年第8期2924-2929,共6页China Environmental Science

基　　金：国家自然科学基金项目(21377023)

摘　　要：采用UV/N_O2^-/NO_3^-体系作为目标研究体系,探究体系中4C2NP/4N2CP/2NP/4CP等4种酚类苯系物的降解动力学和取代基转化情况,揭示UV/(亚)硝酸盐体系中氯代硝基物的具体降解机理.在p H=1.50时,UV/NO_2^-/NO_3^-体系中的4C2NP反应速率常数均达到最大,为10.3×10^(-4)min^(-1).在不同p H值条件下,由于硝基取代基的致钝化作用,使UV/NO_2^-/NO_3^-体系中的2NP降解速率受抑制程度最显著,即2.5×10^(-4)min^(-1)(p H=1.50)和0(p H=5.50).UV/NO2-/NO3-/4CP体系中,涉及的反应机理主要包括再硝化、再氯化、脱硝基氯化和氧化等过程,揭示了无机(亚)硝酸盐与硝基取代基的释放/积累的转化过程,以及氯取代基与无机氯离子之间的相互转化过程.Degradation kinetics and substituents transformation mechanisms of different substituted phenols(4C2NP/4N2CP/2NP/4CP)in the objective UV/NO2-/NO3-system were investigated.In this study,several specific decomposition mechanisms of the studied substrates were proposed.At pH=1.50,the highest reaction rate constant was observed in the UV/NO2-/NO3-system,reaching10.3×10-4min-1.In the objective UV/NO2-/NO3-system,the decomposition rate of2NP was inhibited indistinctively at different pH values due to the characteristic of nitro substituent having an significantly negative influence in benzene activation.Based on the major intermediates identified,re-nitration,chlorination,denitrochlorination and oxidation mechanisms were mainly involved in UV/NO2-/NO3-/4CP system,which revealed the release/accumulation processes of nitro substituent and the mutual transformations between chloro substituent and chloride ion.

关 键 词：紫外光 (亚)硝酸盐 硝化剂 氯/硝基取代基 转化机理 

分 类 号：X703[环境科学与工程—环境工程]