Mechanism and kinetics study on the ozonolysis reaction of 2,3,7,8-TCDD in the atmosphere  

作　　者：Jing Bai Xiaomin Sun Chenxi Zhang Chen Gong Jingtian Hu Jianghua Zhang 

机构地区：[1]Environment Research Institute, Shandong University [2]School of Management, Shandong University

出　　处：《Journal of Environmental Sciences》2014年第1期181-188,共8页环境科学学报（英文版）

基　　金：supported by National Natural Science Foundation of China(No.21277082,21177076,71201093);the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province(No.BS2012HZ009,BS2012SF012);the Hi-Tech Research and Development Program(863)of China(No.2012AA06A301);the New Century Excellent Talents in University(NCET-13-0349);the Open Project from special fund of State Key Joint Laboratory of Environment Simulation and Pollution Control(No.13K05ESPCP)

摘　　要：The ozonolysis of 2,3,7,8-tetra-chlorodibenzo-p-dioxin （2,3,7,8-TCDD） is an efficient degradation way in the atmosphere. The ozonolysis process and possible reactions path of Criegee Intermediates with NO and H2O are introduced in detail at the method of MPWB1K/6-31＋G（d,p）//MPWB1K/6- 311＋G（3df,2p） level. In ozonolysis, H2O is an important source of OH radical formation and initiated the subsequent degradation reaction. The Rice-Ramsperger-Kassel-Marcus （RRKM） theory was applied to calculate rate constants with the temperature ranging from 200 to 600 K. The rate constant of reaction between 2,3,7,8-TCDD and 03 is 4.80 × 10^-20 cm3/（mole.sec） at 298 K and 760 Tort. The atmospheric lifetime of the reaction species was estimated according to rate constants, which is helpful for the atmospheric model study on the degradation and risk assessment of dioxin.The ozonolysis of 2,3,7,8-tetra-chlorodibenzo-p-dioxin （2,3,7,8-TCDD） is an efficient degradation way in the atmosphere. The ozonolysis process and possible reactions path of Criegee Intermediates with NO and H2O are introduced in detail at the method of MPWB1K/6-31＋G（d,p）//MPWB1K/6- 311＋G（3df,2p） level. In ozonolysis, H2O is an important source of OH radical formation and initiated the subsequent degradation reaction. The Rice-Ramsperger-Kassel-Marcus （RRKM） theory was applied to calculate rate constants with the temperature ranging from 200 to 600 K. The rate constant of reaction between 2,3,7,8-TCDD and 03 is 4.80 × 10^-20 cm3/（mole.sec） at 298 K and 760 Tort. The atmospheric lifetime of the reaction species was estimated according to rate constants, which is helpful for the atmospheric model study on the degradation and risk assessment of dioxin.

关 键 词：ozonolysis reaction of 2 3 7 8-TCDD chemical mechanism and kinetics study rate constants atmospheric lifetime 

分 类 号：X131.1[环境科学与工程—环境科学]