20140219891 | SEPARATION METHOD OF ZIRCONIUM AND HAFNIUM BY SOLVENT EXTRACTION PROCESS - A separation method of zirconium and hafnium is described which includes an extraction process of agitating an undiluted aqueous solution containing zirconium, hafnium, and sulfuric acid with a first stirring solution containing an acidic extractant to produce a first extract solution in which the hafnium is extracted by the acidic extractant; and a recovery process of agitating the first extract solution with a second stirring solution containing a citric acid solution to produce a citric acid solution after extraction in which zirconium is reverse-extracted from the first extract solution to the citric acid solution so as to recover zirconium contained in the first extract solution. The method may reduce the amount of extractant while greatly enhancing the separation effect of zirconium and hafnium, and increase zirconium recovery rate by more than 97% through an additional zirconium recovery process while reducing a hafnium content in zirconium by less than 50 ppm. | 08-07-2014 |