STUDY ON SEPARATION AND DETERMINATION OF RARE EARTH ELEMENTS IN ORE IN VIETNAM BY CAPILLARY ELECTROPHORESIS CAPACITIVELY COUPLED CONTACTLESS CONDUCTIVITY DETECTION

Abstract

     Nowadays, rare earth elements have become strategic materials for high-tech industries. The mostpopular rare earth elements in ore of Vietnam are Lanthanum (La), Cerium (Ce), Praseodymium(Pr), Neodymium (Nd), Samarium (Sm). Capillary electrophoresis (CE) with capacitively coupledcontactless conductivity detection (C4D) has been considered as a new analytical technique inVietnam, which is simple, low cost, automatic and able to be used in the field with small amountsof samples and chemicals. The separation conditions of 5 rare earth elements by semi-automaticCE-C4D were optimized. Electrolyte solution consisting of 20 mM Arginine; 44 mM Ascorbic; 6,7mM α-HIBA and 5% methanol; pH 4,2. Detection limits in range of 7.92 to 34.8 μM wereachieved for 5 rare earth elements. The analysis of two ore samples was demonstrated. Theseresults were compared with the results ofstandard method (Inductively Coupled Plasma - OpticalEmission Spectrometry ICP-OES) shored the highly reliable results.