PURPOSE: To carry out the back extraction of accumulated Fe(III) rapidly, and to regenerate the titled extractant at a low cost, by using di-2-ethylhexyl phosphate as an extractant, and contacting the used extractant with an aqueous solution of phosphoric acid.
CONSTITUTION: Di-2-ethylhexyl phosphate (D2EHPA) is used as an extractant for the solvent extraction of e.g. U, rare earth metal, Ni, Co, In, Sn, etc., and the used extractant is made to contact with an aqueous solution of phosphoric acid. The use of an aqueous solution of phosphoric acid as a back extraction agent enables the rapid back extraction of Fe(III) which is especially difficult to be separated by back extraction from D2EHOA, and accordingly, enables the regeneration of the extractant at a low cost. The required concentration of phosphoric acid in the aqueous solution for the back extraction is 6W30N, and preferably 15W27N.
TAKAYANAGI SATORU
KOBAN SUSUMU
Next Patent: PRODUCTION OF HEXAGONAL FERRITE MAGNETIC POWDER