稀土离子的高效毛细管电泳分离和测定

Separation and Determination of Rare Earth Metal Ions With Capillary Ion Electrophoresis

以咪唑为背景电解质，以乳酸作为络合剂，采用毛细管离子电泳（ＣＩＥ）间接紫外法，研究了分离与测定稀土离子的方法，考察了背景电解质酸度、络合剂浓度、背景电解质共存离子的浓度、分离电压对稀土离子分离的影响。在选定的实验条件下，１４种稀土离子混合物在６ｍｉｎ内完成分离，检测限可达７．８×１０１４ ｍｏｌ，采用内标标准曲线法对某稀土公司生产的少铕氯化稀土进行了分离与测定。

The separation of rare earth metal ions by capillary zone electrophoresis in the presence of imidazole as UV-absorbing background electrolyte and lactic acid as the complex- ing agent with indirect UV detection was investigated. The effect of acidity, the concentra- tions of complexing agent and coexisting ion and applied voltage on capillary electrophoresis was discussed. By using 0. 02 mol/L imidazole containing 6×103 mol/L lactic acid(pH 3. 4) as a carrier electroiyte, 14 rare earth metal ions were separated within 6 minutes under a posi- tive voltage of 10. 0 kV. The linear range was 1×105～1 × l03(mol/L) for La. Ce and 1 × l05～5 × l04 (mol/L) for Pr .Nd. Sm. The content of La、Ce、Pr、Nd in rare earth chloride sample from a rare earth company was determined successfully with this method.