Selective Recovery of Trace Scandium from Acid Aqueous Solution with (2-Ethylhexyl hydrogen 2-ethylhexylphosphonate)-Impregnated Resin

A reagent-impregnated resin prepared from 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (PC-88A) and Amber-lite XAD-7 beads was examined in order to apply it to the selective recovery of scandium. The distribution ratio of scandium to the present resin is extremely high (log D_??_6), even in highly concentrated acids. The separation factors between Sc(III) and other common metal ions including Fe(III) are sufficiently large to allow effective separations. The selective recovery of Sc(III) from the acid-leached solutions of wolframite and tin slag has been carried out by using the present resin as the column stationary phase. The retained Sc(III) is released from the resin quantitatively by elution with 4-methyl-2-pentanone. Scandium has been isolated as a precipitate by treating Sc-PC-88A complex with oxalic acid in ethanol.