超声提取-改进BCR法测定PM_(2.5)中6种重金属元素的化学形态  

Determination of Chemical Speciation of 6 Heavy Metals in PM_(2.5) with Ultrasonic Extraction-Modified BCR Procedure

作　　者：杨华[1] 吴宇峰[1] 王静[1] 闫荣馨 张永刚[2] 

机构地区：[1]天津市环境监测中心,天津300191 [2]天津创业环保集团股份有限公司,天津300381

出　　处：《理化检验（化学分册）》2015年第8期1154-1158,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：天津市科学技术委员会重点项目(13ZCZDSF14600)

摘　　要：应用改进的BCR法对大气微颗粒物(PM2.5)进行分析,用超声法代替原来的机械振荡法,对所采得的微颗粒物样品中6种重金属元素(铜、锌、铅、镉、镍、铬)的4种化学形态(酸可交换态F1,可还原态F2,可氧化态F3及残渣态F4)进行分别提取,所得各形态溶液中的金属元素含量用电感耦合等离子体质谱法测定。结果表明:超声提取法的提取时间仅为30min(对F1及F2)和20min(对F3),而原方法需16h;而且超声提取的效率较高,是原方法的89.5%~133%;6种元素的化学形态测定结果的相对标准偏差(n=8)均小于25%。此外,样品中的元素形态总量(ng·m-3)与元素全量(ng·m-3)之间的偏差在-30.7%^-11.5%之间。Ultrasono-extraction was used to substitute the original shaking extraction to extract separately the 4 species （the acid-exchangeable species F1, the reducible species F2, the oxidizable species F3 and the residual species F4） of 6 heavy metals （i. e. , Cu, Zn, Pb, Cd, Ni and Cr） in PM2.s micro particles by the modified BCR method. ICP-MS was applied to the determination o{ the 6 metal ions of various chemical species in the extracts. It was shown that the ultrasono-extraction not only requires less time for extraction （requiring only 30 min for F1, F2 and 20 rain for F3 instead of 16 h in the original procedure）, hut also has higher extraction efficiency （amounting to 89.5%--133% as referring to the original procedure）, and better precision [-having values of RSD＇s （n=8） for the 6 cations in various chemical species less than 25%] and satisfactory accuracy [-giving relative deviation between values of the total amount （in ng · m-3） of the 4 chemical species and the total amounts （in ng · m-a） of the metals in the sample ranged from -30. 7% to -11.5%].

关 键 词：超声提取 改进BCR法 PM2.5微颗粒物 重金属元素 化学形态 

分 类 号：O657.63[理学—分析化学]