激光剥蚀电感耦合等离子体质谱法测定镀锌钢板镀层中的铅、镉、砷、锡和锑

本文以64Zn为内标，以纯锌标准物质作校准曲线，建立了激光剥蚀电感耦合等离子体质谱法（LA-ICP-MS）测定镀锌层中Pb、Cd、As、Sn和Sb的方法。研究了镀锌钢板镀层表面状态和LA的深度分辨率，选择单点剥蚀方式和ICP-MS时间分辨模式采集数据。在优化工作参数基础上，探讨了分馏效应，Pb、Sn的分馏因子接近1，As、Cd、Sb的分馏因子都小于0.8，因而认为Pb、Sn没有分馏效应，As、Cd、Sb存在分馏效应。测定了标准物质和实际样品，测定结果与标称值（ICP-MS测定值）基本相吻合，因而认为该方法是可行的。Pb、Cd、As、Sn和Sb的检出限分别为3、0.3、3、3和0.5 μg/g。

Determination of lead,cadmium,arsenic,tin and antimony in coating layer of galvanized steel sheet by laser ablation inductively coupled plasma mass spectrometry

A determination method of lead,cadmium,arsenic,tin and antimony in galvanizing layer by laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) was established using 64Zn as internal standard based on the calibration curve prepared by pure zinc certified reference material.The surface state of coating layer of galvanized steel sheet and the depth resolution of laser ablation were studied.The data acquisition was carried out using single-point ablation mode and ICP-MS time resolution mode.On the basis of optimizing operation parameters,the fractionation effect was discussed.The results showed that the fractionation factors of Pb and Sn were close to 1,while the fractionation factors of As,Cd and Sb were less than 0.8.Therefore,it was considered that Pb and Sb had no fractionation effect,while As,Cd and Sb had fractionation effect.The memory effect was not observed.This method has been applied to determination of certified reference materials and actual samples,and the results were consistent with the certified values(found by ICP-MS),which proved that the proposed method was feasible.The detection limits of Pb,Cd,As,Sn and Sb were 3,0.3,3,3 and 0.5 μg/g,respectively.