快速溶剂萃取-气相色谱-质谱联用法测定土壤中多氯联苯Aroclor系列

GC-MS Determination of Aroclors in Soil with Rapid Solvent Extraction

采用气相色—夸质谱法在选择离子方式下测定土壤中多氯联苯Aroclor系列Aroclor1016、Aroclor1221、Aroclor1232、Aroclor1242、Aroclor1248、Aroclor1254、Aroclor1260。样品经正己烷-丙酮（体积比1比1）混合溶剂进行快速溶剂萃取仪提取后，经浓硫酸．液_液分配，再经氟罗里硅土柱净化浓缩，洗脱液浓缩并定容至1mL后，供气相色沓质谱仪测定，外标法定量。回收率在76％～108％之间，相对标准偏差（n=7）小于139／6。应用提出的方法分析了-个土壤标样物质，测定结果（2．19mg·kgl）与证书值（2．14mg·kg叫）之间的相对误差为2．3％。以土壤样品为基体，加入十氯联苯替代物的标准溶液做回收试验，测得回收率在70％～120％之间。

7 Aroclors, namely Aroclor 1016, Aroclor 1221, Aroclor 1232, Aroclor 1242, Aroclor 1248, Aroclor 1254 and Aroclor 1260, in soil were determined by C-C-MS under selective ion monitoring mode. The sample was extracted with n-hexane and acetone mixed in the ratio of 1 to 1 by rapid solvent extractor, and then partitioned with conc. H2SO4. The extract was purified by passing through florisil column. The eluate was concentrated and made up to 1 mL, which was used for GC-MS determination, with external standard method. Values of recovery were found in the range of 76%-108% with RSD＇s （n=7） less than 13%. In application of the proposed method to the analysis of a CRM of soil, the relative error between the result obtained （2. 19 mg · kg-1） and the certified value （2. 14 mg· kg-1） was found to be 2. 3%. Tests for recovery and precision were made by addition of standard solution of the substitute decachlorobiphenyl to a soil sample as matrix which was then analyzed by the proposed method. Values of recovery obtained were in the range of 70%-120%.