AG-MP-1M在氢溴酸体系中分离镉的方法

Separation of Cadmium in Hydrobromic Acid by Anion Resin AG-MP-1M

Cd同位素质谱分析中存在的质谱干扰有110 Pd、70 Zn 40 Ar、95 Mo 16 O、112 Sn、113 In、114 Sn和98 Mo 16 O等。因此在分析前应将Cd元素与产生干扰的其他元素分离,以避免测量过程中的质谱干扰。目前分离Cd的常用方法通常采用盐酸体系,分离过程中存在Sn与Cd分离困难的问题,操作步骤繁琐且淋洗体积大。针对上述问题,本工作开发了用阴离子树脂AG-MP-1M在氢溴酸体系中分离Cd的方法,采用混合酸消解的方法将样品消解完全后,用1 mL 0.25 mol/L的氢溴酸溶解样品并上柱,用3 mL 0.25 mol/L氢溴酸淋洗后可将绝大部分Sn、Zn、Mo等元素分离,然后用1 mL 2 mol/L盐酸和3 mL 0.5 mol/L盐酸淋洗Pb等其它元素,最后,用3 mL 0.002 mol/L盐酸解吸Cd。实验表明Cd回收率可达99.1%,且能将Sn、Zn、Mo等产生干扰的元素完全分开。采用此方法分离Cd总的淋洗体积为10 mL,和之前文献报道的方法相比大量减少了淋洗体积。该方法提高了Cd的分离效果,节约了实验流程时间,可用于Cd含量测试和Cd同位素测试的前处理工作中。

The mass spectral interference existed in the process of Cd isotopes analysis by mass spectrometry,including 110 Pd,70 Zn 40 Ar,95 Mo 16 O,112 Sn,113 In,114 Sn and 98 Mo 16 O.Therefore,in order to avoid mass spectral interference of Cd isotopes,there should be separated before the isotope analysis.A hydrochloric acid system was used as a commonly method to separate Cd,but the elution of Sn was difficult and the volume of elution was large.Aiming at the above problems,a method for separating Cd in hydrobromic acid system using anionic resin AG-MP-1M was developed.After the sample was completely digested by the mixed acid,the sample was dissolved with 1 mL 0.25 mol/L hydrobromic acid.After loading on the column,washing 3 mL 0.25 mol/L hydrobromic,most ions such as Sn,Zn,Mo could be separated,and other elements such as Pb were washed with 1 mL 2 mol/L hydrochloric acid and 3 mL 0.5 mol/L hydrochloric acid,and Cd was rinsed with 3 mL 0.002 mol/L hydrochloric acid.By these processes,the yield of Cd is 99.1%,and the interference elements such as Sn,Zn,and Mo can be completely separated.Comparing with the method reported in the literature,this separation method of Cd significantly reduces the elution volume.The total elution volume is 10 mL,and Sn and Cd can be completely separated.This method improves the separation efficiency of Cd,which can be used in the measurement of Cd isotopes and Cd concentrations.