METHOD FOR OBTAINING A MIXTURE OF ZIRCONIUM AND HAFNIUM NITRATE AND OXYNITRATE CRYSTALS Russian patent published in 2022 - IPC C01G25/00 C01G27/00 

FIELD: zirconium and hafnium compounds obtaining.

SUBSTANCE: invention relates to a technology for obtaining compounds of zirconium and hafnium and can be used to obtain a mixture of crystals of nitrate and oxynitrate of zirconium and hafnium. Zirconium and hafnium from the feedstock are converted into a water-soluble compound by treating the feedstock with a fluorine- or chlorine-containing reagent, primary purification of impurities is carried out by isolating potassium fluorozirconate and fluorohafnate or zirconium and hafnium tetrachlorides, after which they are alkalinely treated in a solution of potassium hydroxide or sodium hydroxide at a temperature of 50-60°C, followed by water washing of the resulting zirconium and hafnium hydroxides, which are used to prepare a nitric acid solution by dissolving them in nitric acid, then the extraction separation of the solution is carried out to obtain pure re-extracts, evaporation of the obtained re-extracts and separation of a mixture of nitrate crystals and zirconium and hafnium oxynitrate.

EFFECT: improvement of technology for obtaining compounds of zirconium and hafnium.

2 cl, 2 tbl, 6 ex