原子吸收光谱法间接测定高纯碳酸锂中微量氯

Indirect Determination of Trace Cl^- in High Pure Li_2CO_3 with Atomic Absorption Spectromete

利用Ag+与Cl-生成AgCl沉淀的反应,采用原子吸收光谱法测定过量Ag+浓度,从而间接测定样品中Cl-含量。研究了样品处理及沉淀条件的选择,实验结果表明,采用体积比为1∶1的硝酸溶样;加入过量AgNO3,溶液放置24h,可保证AgCl沉淀完全。本法简便、快速,方法检出限为0.021μg·mL-1;变异系数1.7%,回收率98.8%,能满足测定要求。

Using the reaction of Cl- to Ag+ to produce AgCl precipitate ,the concentration of Cl- in sample was determined indirectly by the examination of excessive Ag+ with AAS. In the experiment the solvent and precipitate condition were examined. The results showed that 1∶1 (volume)HNO3 is a good solvent for dissolution of sample, and AgCl can be deposited completely after 20?h. The determination limit of the method is 0.021?μg·mL-1. RSD is 1.7%. Average recovery rate is 98.8%. 