临沂市夏季大气中醛酮类化合物的污染状况研究

Study on the Pollution Status of Ambient Aldehydes and Ketones in Linyi City in Summer

为探究临沂市醛酮类化合物的污染状况,于2020年7~9月利用2,4-二硝基苯肼衍生化采样管采样/高效液相色谱方法在两个不同功能区站点对环境空气中醛酮类化合物进行监测。并利用比值法对醛酮类化合物的来源进行了初步分析,同时计算了主要醛酮类化合物的臭氧生成潜势。研究表明两个站点醛酮类化合物总的体积分数日均值分别为15.03nmol/mol和23.57nmol/mol,其中甲醛浓度最高,其体积分数分别占总体积的44.5%和57.0%。两个站点的臭氧生成潜势OFP分别为120.51μg/m^(3)和182.08μg/m^(3),其中甲醛的贡献率最大,分别为54.9%和71.2%。雕塑公园与探沂镇政府驻地的甲醛/乙醛(C1/C2)浓度比分别为1.28和2.84表明,前者比较符合城市站点特征,主要来源于机动车尾气等,而探沂镇政府驻地甲醛浓度相对较高,主要来源于附近的板材生产基地。研究表明,为了减少醛酮类化合物对臭氧的贡献率,临沂市应加强对机动车、板材企业排放醛酮类化合物的管控。

In order to investigate the pollution characteristics of aldehydes and ketones in Linyi City,the aldehydes and ketones in the ambient air were monitored by 2,4-dinitrophenylhydrazine derivated sampling tube sampling/high performance liquid chromatography method at two stations in different functional areas from July to September 2020.Besides,the sources of aldehydes and ketones were analyzed by the ratio method,and the ozone generation potential of the main aldehydes and ketones was calculated.The results showed that the daily average volume fractions of total aldehydes and ketones at two sites were 15.03nmol/mol and 23.57 nmol/mol,respectively.Formaldehyde concentration was the highest,accounting for 44.5%and 57.0%of the total volume,respectively.The ozone formation potential(OFP)at the two sites was 120.51μg/m^(3)and 182.08μg/m^(3),respectively.Among them,the contribution rate of formaldehyde to the total OFP was also the largest,which were 54.9%and71.2%respectively.The formaldehyde/acetaldehyde(C1/C2)concentration ratio of the sculpture park and the government residenceof Tanyi Town were 1.28 and 2.84,respectively,indicating that the former was more consistent with the characteristics of the city site,mainly from vehicle exhaust,while the formaldehyde concentration of the government residence of Tanyi town was relatively high,mainly from the nearby plate production base.The research shows that in order to reduce the contribution rate of aldehydes and ketones to ozone,Linyi city should strengthen the control of aldehydes and ketones emitted by motor vehicles and plate enterprises.