DETERMINATION OF RARE-EARTH ELEMENTS IN SOME TECHNICAL MATERIALS BY CAPILLARY ISOTACHOPHORESIS

The method of capillary isotachophoresis was adopted for the determination of rare earth elements. The following operating system was used: leading electrolyte -0.030 mol.1-1 KOH (K+ -leading ion), 0.015 mol.l-1 alpha-hydroxyisobutyric acid, 0.05% poly(vinyl alcohol), pH adjusted at 5.5 with acetic acid and terminating electrolyte - 0.010 mol.l-1 beta-alanine, pH adjusted at 5.0 with acetic acid. The qualitative isotachophoretic characteristics (relative zone heights) of the rare earth elements and of a number of other metal elements were measured. The method was used for analysis of real samples (wet process phosphoric acid, intermediate products of rare earth elements separation, polishing powders based on cerium oxide, Y2O2S:Eu luminescent material, and high-T(c) superconductor). The results are in good agreement with those obtained by other analytical methods.