"Individual Separation of Yttrium and Dysprosium Oxides from the Rare Earths Product obtained from Xenotime Mineral Concentrate"

Abstract

The separation of ytrrium and dysprosium from the REEs product (48.15% Y2O3, 11.05% Dy2O3) obtained from a xenotime mineral concentrate was studied. The REEs chloride liquor is prepared followed by precipitation of yttrium using lactic acid. The optimum conditions of the yttrium precipitation included 2 M lactic acid concentration, lactic acid pH 5 with L(REEs solution) /L(lactic acid) 1/0.75 at contact time of 168 h at 25 o C. The extraction of dysprosium from Y-free REE chloride solution was investigated using PC88A (2-Ethylhexyl 2-ethylhexy phosphonic acid). The optimal conditions of the dysprosium extraction were an extractant concentration of 2.2 M, 1/1 O/A ratio in a chloride solution at pH 3, and 9 min., as contact time. While the optimal conditions of its stripping considered 1.5 M H2SO4 in 1/1 O/A ratio for 20 min., as stripping time. Ultrapure products of Y and Dy were prepared and analyzed using ICP-MS.