4-甲基-2-戊酮萃取分离-电感耦合等离子体质谱法测定高纯硒中17种杂质元素

利用电感耦合等离子体质谱法(ICP-MS)测定5N~6N(纯度为99.999%~99.999 9%)高纯硒中痕量杂质元素时,硒的基体效应明显,影响结果的准确性。采用硝酸溶解高纯硒,经4-甲基-2-戊酮选择性萃取硒后,对水相进行测定,建立了电感耦合等离子体质谱法测定高纯硒中的Li、Be、B、Sc、Ti、V、Cr、Mn、Co、Ni、Cu、Zn、As、Sr、Cd、Ba、Pb共17种痕量杂质元素的方法。实验表明,萃取时当盐酸浓度为7mol/L、MIBK体积为20mL和萃取时间为2min时,水相中硒的质量浓度低于5mg/L,此时硒基体对测定的影响可忽略。方法中各元素校准曲线的线性关系均大于0.999 5,各待测元素的方法检出限为0.2~7.0ng/g。按照实验方法对高纯硒样品中这17种杂质元素进行测定,测定结果的相对标准偏差(RSD,n=6)在5.0%~11.2%之间,加标回收率在91%~103%之间。

Determination of seventeen impurity elements in high purity selenium by inductively coupled plasma mass spectrometry after extraction separation with 4-methyl-2-ketone

During the determination of trace impurity elements in high-purity selenium (5 N-6 N) by inductively coupled plasma mass spectrometry (ICP-MS), the matrix effect of selenium was obvious and influenced the accuracy of determination results. The high purity selenium was dissolved with nitric acid. After selective extraction of selenium with 4-methyl-2-ketone (MIBK), the water phase was determined. Thus, a determination method of 17 impurity elements (including Li, Be, B, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Sr, Cd, Ba and Pb) in high-purity selenium by ICP-MS was established. The experiments showed that the mass concentration of selenium in water phase was less than 5mg/L under the following conditions: the concentration of hydrochloric acid was 7mol/L, the volume of MIBK was 20mL and the extraction time was 2min. As a result, the influence of selenium matrix on the determination could be ignored. The linear correlation coefficients of calibration curves of elements in this method were all higher than 0.9995. The detection limits of method of elements were between 0.2ng/g and 7.0ng/g. Seventeen impurities in high purity selenium sample were determined according to the experimental method. The relative standard deviations (RSD, n=6) of determination results were between 5.0% and 11.2%. The recoveries of standard addition were between 91% and 103%.