EXTRACTION SEPARATION OF ZIRCONIUM AND HAFNIUM Russian patent published in 2014 - IPC C01G25/00 C01G27/00 

FIELD: process engineering.

SUBSTANCE: invention relates to hydrometallurgy of zirconium and hafnium. Proposed method comprises total extraction of zirconium and hafnium from initial solution nitrate using the tribytilphosphate solution in hydrocarbon diluent. Then, they are separated at decrease in acidity with extraction of zirconium from hafnium re-extract by return extragent with combination of both extracts in the flow and weak-acid zirconium re-extraction with subsequent recovery of extragent. After total extraction, combined extract is flushed with nitric acid solution with concentration equal to nitric acid content in initial solution. Then, hafnium re-extraction is performed. Now, a portion of hafnium re-extract flow is returned back to cycle start for it to be fed along with initial solution at preset acidity while other portion is directed to additional extraction of zirconium.

EFFECT: high-purity concentrated hafnium, decreased amount of reagents for further processing.

7 cl, 2 dwg, 2 tbl, 2 ex