Waste printed circuit boards(W-PCBs) were multiple smashed and separated, then passed through a 60-mesh screen, treated with hydrochloric acid (2 mol/L), ultrapure water and dehydrated with acetone successively.The filter residue and filter paper were filled into the extraction pool, or inserted into Soxhlet Extraction tube parceled with new filter paper.After addition of 5 μL of internal standard substance, the filter residue above was respectively extracted by Soxhlet Extraction (SE) method or Accelerated Solvent Extraction (ASE) method, cleaned with multi-layer silica gel column and activated-charcoal column to obtained the dioxins samples.The samples were analyzed by isotope dilution high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS).The effects of SE and ASE method and number of chlorines atoms on recovery of 15 kinds of 13C-2,3,7,8 PCDD/Fs were investigated, and the accuracy and precision of the two extraction methods were compared.The results show that, the recovery of 15 kinds of 13C-2,3,7,8 PCDD/Fs using ASE method is 54.3%-113.0%, and that of SE is 28.3%-77.7%, and the Toxic Equivalent Quangtity (TEQ) in W-PCBs is 0.075 ng/kg (TEQ) and 0.266 ng/kg (TEQ) using ASE and SE method respectively.Under the premise that accuracy and precision meet with the international standard, ASE is simple, rapid, solvent-free and accurate.%将经过多级破碎分选所得的废线路板粉末过60目筛,以2 mol/L HCl溶液、超纯水洗涤,并用丙酮脱水.将预处理后的滤渣、滤纸填入萃取池,或者用新滤纸包裹后置于索氏提取管内,添加5 μL内标物,分别用加速溶剂萃取法(ASE)或索氏提取(SE)法进行萃取,依次采用多层硅胶柱和活性炭柱对萃取提取物进行净化、洗脱,得到二噁英测试样品.用同位素稀释-高分辨气相色谱-质谱联用仪分析样品中二噁英的含量.考察两种提取方法及不同氯代数对15种13C-2,3,7,8-PCDD/Fs回收率的影响,比较两种方法的准确度和精密度.结果表明,ASE和SE对15种13C-2,3,7,8-PCDD/Fs的回收率分别为54.3%~113.0%和28.3%~77.7%, 实测废线路板中二噁英毒性当量(Toxic equivalent quangtity,TEQ)分别为0.075 ng TEQ/kg和0.266 ng TEQ/kg.在方法精密度允许范围内,ASE相对具有简单快速、溶剂用量少和准确的优势.
展开▼
