摘要
作为大气二次污染的关键前体物,挥发性有机物(VOCs)大气氧化机理十分复杂,目前模型模拟普遍存在VOCs转化过程的总碳质量难以闭合的问题.为了对VOCs氧化机理有更全面的认识,本研究基于零维盒子模型构建了拉格朗日模拟体系,采用6种广泛应用的大气化学机理,选取4种代表性VOCs物种和56种光化学评估(photochemical assessment monitoring station,PAMS)组合气团,系统开展了逐代氧化过程的碳平衡模拟与评估.研究结果表明,6种化学机理模拟均存在显著的碳质量缺失现象(7.5%~76%),且不同机理和不同组分间呈现明显差异.其中,MCMv3.3.1机理碳缺失程度最低且总碳质量开始缺失对应的OH暴露量最高.在单个物种氧化的碳平衡情况中,正戊烷的氧化过程中碳缺失最为严重,其次是甲苯的氧化过程.总碳质量缺失的发生主要与第一代产物的化学消耗和第二代产物的生成有关.本研究结果为完善有机物种氧化机理、提升化学机理完整性提供了重要科学依据.
As a key precursor to secondary air pollution,the atmospheric oxidation mechanism of volatile organic compounds(VOCs)is very complex,and the current model simulation generally has the problem that the total carbon mass of VOCs conversion process is difficult to close.Aiming for a more comprehensive understanding of the oxidation mechanism of VOCs,this study constructed a Lagrangian simulation system based on the zero-dimensional box model,using 6 widely used atmospheric chemical mechanisms,selecting 4 representative VOCs species and 56 PAMS(Photochemical Assessment Monitoring Station)combined air masses,and systematically carrying out the carbon balance simulation and evaluation of the generational oxidation process.The results showed that there was a significant carbon mass loss phenomenon(7.5%~76%)in the simulation of the six chemical mechanisms,and there were obvious differences between different mechanisms and components.Among them,MCMv3.3.1 had the lowest degree of carbon deletion and the highest OH exposure corresponding to the loss of total carbon mass.In the oxidized carbon balance of a single species,the carbon loss was the most serious during the oxidation of n-pentane,followed by the oxidation process of toluene.The occurrence of total carbon mass loss is mainly related to the chemical consumption of the first generation products and the generation of the second generation products.The results of this study provide an important scientific basis for improving the oxidation mechanism of organic species and improving the integrity of chemical mechanism.
作者
叶芹文
袁斌
杨晓韵
彭钰雯
刘思利
杨素霞
宋永欣
邵敏
YE Qin-wen;YUAN Bin;YANG Xiao-yun;PENG Yu-wen;LIU Si-li;YANG Su-xia;SONG Yong-xin;SHAO Min(Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality,Institute for Environmental and Climate Research,College of Environment and Climate,Jinan University,Guangzhou 511443,China;Guangzhou Research Institute of Environment Protection Co.,Ltd.,Guangzhou 510620,China)
出处
《中国环境科学》
北大核心
2025年第10期5399-5409,共11页
China Environmental Science
基金
国家重点研发计划项目(2023YFC3706200)。
关键词
盒子模型
碳平衡
化学机理
挥发性有机物氧化机理
box model
carbon balance
chemical mechanism
oxidation mechanism of volatile organic compounds
