The invention relates to a method for fractionating, extracting and separating
zirconium and
hafnium, in particular to a method for fractionating, extracting and separating
zirconium and
hafnium by using di(2-ethylhexyl)
phosphorous acid as an extracting agent. The method comprises the following steps of: (1) extraction, using 50-300 parts by weight of di(2-ethylhexyl)
phosphorous acid, 25-150 parts by weight of mixing
alcohol with the
carbon number of 7-9, and 550-925 parts by weight of sulfonated
kerosene to prepare a di(2-ethylhexyl)
phosphorous acid organic phase to extract; (2) washing, adding
oxalic acid into a sulphuric acid solution to prepare a washing solution to wash; and (3) stripping, using a mixing solution of
ammonia and
carbonate as a strip liquor, stripping to obtain a strip liquor containing
hafnium, slowly adding concentrated
hydrochloric acid to adjust the solution into acidity, adding concentrated
ammonia to obtain hafnium
hydroxide precipitate, washing, filtering, calcining, and then obtaining
hafnium oxide. The used
chemical agents are difficult to volatilize, the
toxicity is low, the
corrosion is weak, the disposition is easy, and the discharged waste water can not cause the environments to be polluted. The technology has the advantages of quick phase separation, convenient operation, and high and stable product quality.