大气环境中氧化基体对VOCs测定的影响  

Effects of oxidizing matrix on VOCs detection of atmosphere samples

作　　者：曹方方 石敬华 钟琪[2] 陈烨[2] 张凤菊 由希华 梁宵[2] 许秀艳[2] 李红莉 许杨 CAO Fangfang;SHI Jinghua;ZHONG Qi;CHEN Ye;ZHANG Fengju;YOU Xihua;LIANG Xiao;XU Xiuyan;LI Hongli;XU Yang(Shandong Ecology and Environment Monitoring Center,Jinan,250101,China;China National Enviromental Monitoring Center,Beijing,100012,China)

机构地区：[1]山东省生态环境监测中心,济南250101 [2]中国环境监测总站,北京100012

出　　处：《环境化学》2025年第3期916-924,共9页Environmental Chemistry

基　　金：国家重点研发计划(2023YFC3705500);2020年度山东省自然科学基金重大基础研究项目(ZR2020ZD21)资助。

摘　　要：大气中挥发性有机物(volatile organic compounds,VOCs)种类多,活性强,部分VOCs在采样、分析过程中会与大气中的氧化基体发生反应.为研究大气中氧化基体对VOCs测定的影响,选择苏玛罐与KI小柱联用,采集去除氧化性基体的样品,与未去除氧化性基体的样品比较,探讨大气中氧化性基体对VOCs测定的影响.结果表明,去除氧化性基体的样品定性检出的化合物种类多,共定性检出110种化合物,未去除氧化基体样品定性检出的化合物种类少,共定性检出40种化合物;氧化基体的存在影响VOCs的浓度和组成,去除氧化基体的总挥发性有机物(TVOCs)平均浓度为144.8 nmol·mol^(−1),其中烷烃为体积分数最大的组分,占81.9%,其次是卤代烃、烯烃、芳香烃和含氧有机物,分别占7%、6.5%、3.2%和1.4%,未去除氧化基体TVOCs平均浓度为32.5 nmol·mol^(−1),其中烷烃、氯代烃占比最高,分别占38.9%和37.5%,其次是芳香烃、烯烃和含氧有机物,分别占11.5%、6.5%和5.6%.大气中氧化性基体影响臭氧生成潜势(ozone formation potential,OFP)理论计算值及对OFP贡献优势物种的判断,去除氧化性基体样品的OFP高(平均值254.1μg·m^(−3)),各物种对OFP贡献大小的顺序为烷烃(67.5%)>烯烃(22.8%)>芳香烃(9.5%)>含氧有机物(0.2%);未去除氧化性基体样品的OFP值低(平均值44.6μg·m^(−3)),各物种对OFP贡献大小的顺序为芳香烃(40.0%)>烯烃(30.6%)>烷烃(28.7%)>含氧有机物(0.8%);去除氧化基体样品的OFP高于臭氧实测浓度,且与臭氧浓度具有很好的一致性,未去除氧化性基体样品的OFP值低于臭氧浓度,去除氧化性基体后采集的样品更符合大气VOCs的真实状态,未来大气VOCs监测,采样时应考虑联用KI小柱去除大气中存在的氧化基体.There are many kinds of Volatile organic compounds,they have strong activity and parts of them will have reactions with the oxidants exist in the atmosphere during sampling and analysis.In order to study the influence of oxidant substances on VOCs determination,two kinds of samples were collected,one(oxidant substances removed sample)was collected with a sampling method that connected Suma canister with KI column to remove oxidant substances,the other(oxidant substances non-removed sample)was collect by Suma canister as usual with oxidant substances in it,compared the determination results between two samples.The results showed that more compounds were qualitatively detected in oxidant substances removed samples,there were 110 compounds were qualitatively detected in oxidant substances removed samples,while 40 compounds were qualitatively detected in oxidant substances non-removed samples.Oxidant substances affects the concentration and composition of VOCs,the average concentration of total volatile organic compounds(TVOCs)of oxidant substances removed samples was 144.8 nmol·mol^(−1),alkanes were the most abundant species,accounted for 81.9%,followed by halogenated hydrocarbon,olefin,aromatic hydrocarbon and OVOCs,accounted for 7%,6.5%,3.2%and 1.4%,respectively;the TVOCs of oxidant substances non-removed samples was 32.5 nmol·mol^(−1),alkane(38.9%)and halogenated hydrocarbon(37.5%)were the most abundant species,then followed by aromatic hydrocarbon(11.5%),olefin(6.5%)and OVOCs(5.6%).The oxidizing matrix affects the ozone formation potential(OFP)and the dominant species.The OFP of the oxidizing matrix sample was 254.1μg·m^(−3),alkanes contributed most(67.5%),then followed by olefins(22.8%),aromatics(9.5%)and oxygenated organic compounds(0.2%);the OFP of oxidant substances non-removed samples was 44.6μg·m^(−3),aromatic contributed most(40.0%),then followed by olefin(30.6%),alkane(28.7%)and oxygenated organic matter(0.8%).The OFP of oxidant substances removed sample was higher than actual ozone concent

关 键 词：苏玛罐采样 大气VOCs 强氧化性基体 臭氧 OFP 

分 类 号：X-1[环境科学与工程] O6[理学—化学]