모나자이트 중의 Y, La, Ce, Pr 및 Nd 들을 pH 8.4에서 EDTA와 착염을 만들어 미리 음이온 교환수지에 EDTA를 흡착시킨 수지관에 용리시켜 희토류 원소들의 분리를 시도하였다. 용리액은 pH 8.4의 EDTA를 사용하였으며, 용리액의 분율에 따라 측정한 각이온의 분리도는 55∼98%이었다.
An anion exchange method for separating the individual rare earth elements in monazite into enriched fractions has been developed. The complexed rare earth ions with EDTA at pH 8.4 pass through the anion resin bed. The absorption order of the complexed ions was in accord with that of the stability constants of the complexes. The elution of a mixture of all the rare earths through an ion-exchange bed with an ammonia-buffered solution of EDTA indicated that this chelating agent is as effective for separating the light rare earths. The separation results of each ion obtained from their elution fractions are 55% to 98%.
