大气细颗粒物(PM_(2.5))中多环芳烃的分析测定与污染特征

Analysis and pollution characteristics of polycyclic aromatic hydrocarbons(PAHs) in PM_(2.5)

采集了北京西三环地区的PM2.5样品,利用超声提取(UE)-固相萃取法(SPE)分离富集得到PM2.5中的多环芳烃(PAHs),对不同的固定相及洗脱液比例进行PAHs回收率比较,得到最优预处理条件.建立了基于HPLC-UV的PM2.5中PAHs分析方法,定量检出17种典型PAHs.对2014年4月12日至2014年5月1日期间PM2.5中PAHs污染特征进行分析,结果显示,PAHs总浓度(∑PAHs)范围为2.6—145.7 ng·m-3,平均浓度为32.2 ng·m-3,不同环数PAHs所占比例顺序为5环>2环>3环>6环>4环,呈富5环的特征.PM2.5质量浓度与∑PAHs及苯并[a]芘(Ba P)均呈现出良好的正相关性,R2分别为0.8和0.6.

PM2. 5 samples were collected from Western 3rdRing-Road in Beijing,and polycyclic aromatic hydrocarbons（ PAHs） in PM2. 5were separated and enriched with ultrasonic extraction（ UE） and solid phase extraction（ SPE）. The optimized condition was obtained by comparing the recovery rates of PAHs with different ratios of stationary phases and eluents. An analytical method for PAHs based on HPLC-UV was established,and 17 PAHs were quantitatively detected in PM2. 5samples. The results showed that the total concentration of PAHs ranged from 2. 6 to 145. 7 ng·m- 3,and the average concentration was 32. 2 ng·m- 3in the samples collected between April 12-May 1,2014. The content of PAHs with different ring numbers followed the order of 5〉 2 〉3 〉6 〉4. Five ring PAHs were enriched. The concentration of PM2. 5was positively correlated with the total concentration of PAHs and Benzo（ a） pyrene（ Ba P）,R2 is 0. 8 and 0. 6.