Method for separating hafnium from zirconium
AssigneeATI Properties, Inc.
InventorsJames A. Sommers, Jeff G. Perrine
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Abstract
A method is provided to optimize separation of zirconium from hafnium by extraction of a feed mix including (Zr+Hf)OCl2 with a thiocyanate-containing organic phase. The method includes maintaining the TA/MO2 ratio in a range from greater than about 2.55 to about 3.5.
Claims21
A method for separating hafnium and zirconium, comprising the steps of:
- (a) extracting an aqueous feed mix comprising zirconium oxychloride and hafnium oxychloride and a thiocyanate salt with a thiocyanate-containing organic solvent to produce a zirconium-containing aqueous raffinate stream and a hafnium-containing organic raffinate stream, wherein the TA/MO2 ratio of the aqueous feed mix is maintained in a range of from greater than about 2.55 to less than about 3.5;
- and
- (b) separating the organic raffinate stream from the aqueous raffinate stream.
A method for making aqueous feed mix lot use in a method for organic extraction of hafnium from zirconium in the presence of thiocyanate, comprising the step of combining:
- (a) an aqueous solution prepared from (Zr+Hf)OCl2.8H2O;
- (b) a solution comprising NH4SCN;
- and
- (c) an amount of hydrochloric acid sufficient to adjust the TA/MO2 ratio of the aqueous feed mix from greater than about 2.55 to about 3.5, wherein the hydrochloric acid is added after the solution comprising NH4SCN.
A method for optimizing organic extraction of hafnium oxychloride from an aqueous feed mix comprising zirconium oxychloride, hafnium oxychloride and thiocyanate ions, comprising the step of maintaining the TA/MO2 ratio of the aqueous feed mix from greater than about 2.55 to about 3.5.
Dependencies are inferred from the claim text.