Recovery of hafnium values from loaded extraction solvent
AssigneeWestinghouse Electric Corp.
InventorHani A. Abodishish
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Abstract
In the production of a highly pure hafnium oxide by calcination of a highly pure hafnium hydroxide, the production of a highly pure hafnium hydroxide from a hafnium-loaded, methyl isobutyl ketone solvent that is substantially free of zirconium and sulfate ions by adding ammonia to such solvent to produce a three-layered reaction product having MIBK solvent on top, ammonium thiocyanate solution in the middle, and a highly pure hafnium hydroxcide sludge at the bottom which is separately removed, freed of water, and calcined.
Claims7
In a process for recovering high purity hafnium hydroxide from a methyl isobutyl ketone organic solvent that is substantially free of sulfate ions and contains hafnium thiocyanate and thiocyanic acid, the improvement comprising reacting said organic solvent with ammonia to produce a reaction product in the form of a methyl isobutyl ketone organic solvent that is substantially free of sulfate ions and contains ammonium thiocyanate solution and hafnium hydroxide;
- separating the constituents of said reaction product in accordance with their respective specific gravities to produce a hafnium hydroxide sludge as one of the separation products;
- and removing the liquid component of said sludge to yield a high purity hafnium hydroxide ready for calcination to hafnium oxide.
Dependencies are inferred from the claim text.