基于SOA和O3生成潜势的上海市VOCs优控物种研究

为评估上海市挥发性有机物(VOCs)对二次有机气溶胶(SOA)和臭氧生成潜势的贡献,采用SUMMA罐采样实验室GC-FID/MS分析方法开展了环境空气104种臭氧前体物和TO-15组分分析,采用DNPH吸附管采样实验室HPLC高效液相色谱法开展了环境空气13种醛酮类组分分析。结果表明:2018年8-11月上海市代表点位VOCs摩尔分数均值范围为20. 61~50. 38 nmol/mol,臭氧生成潜势(OFP)均值范围为60. 55~184. 12μg/m^3,二次有机气溶胶生成潜势(AFP)为21. 63~61. 72μg/m^3。醛酮类和芳香烃类是OFP的主要贡献因子,贡献占比分别为31. 5%~55. 2%和21. 6%~37. 8%。芳香烃类对AFP贡献超过90%。从主要组分构成来看,城区人口密集区点位乙烷、丙烷浓度最高,其他点位甲醛浓度最高;甲醛对OFP贡献最大;间/对二甲苯在浦东书院点位AFP贡献最大,其他点位为甲苯。OFP和AFP双控物种各点位均有4~5个主要物种,以芳香烃类为主。

Study on the Priority Species of VOCs Based on SOA and O3 Formation Potential

In order to evaluate the impactions of VOCs on SOA and ozone formation potential in Shanghai,104 PAMS and TO-15 VOCs species were analyzed by SUMMA tank sampling-GC-FID/MS analysis method,13 OVOCs were analyzed by DNPH sampling-HPLC analysis method. The results showed that the local VOCs concentrations were from 20. 61 to 50. 38 nmol/mol,OFP were from 60. 55 to 184. 12 μg/m^3,AFP were from 21. 63 to 61. 72 μg/m^3 from August to November,2018. Carbonyls and aromatics were the first and second level OFP species,which ratios were from 31. 5% to 55. 2% and from 21. 6% to 37. 8%respectively. The contribution of aromatics to AFP was over 90%. The maximum and sub-maximum concentration species on downtown sites were ethane and propane,while the maximum concentration species was formaldehyde on other sites. The ratio of formaldehyde in OFP was the maximum. The ratio of m-p-xylene in AFP was the maximum on PDSY. The ratio of toluene in AFP were the maximum on other sites. There were 4-5 priority species of both OFP and AFP at each site,they were mainly aromatics.