NIOSHTIC-2 Publications Search
Purification of Zirconyl Sulfate by Solvent Extraction.
MacDonald-DJ; Henry-HG; Bauer-DJ
MISSING :29 pages
The Bureau of Mines has conducted bench-scale investigations leading to the design of an integrated process for producing reactor-grade zirconium oxide (zro2) from zircon sand, which avoids the air pollution, water pollution, fire hazard, and odor problems associated with the hexone-thiocyanate process. The integrated process consists of three steps: production of crude zirconyl sulfate solution, solvent extraction, and production of zro2 from strip liquor. This report describes the solvent extraction step. Multistage, countercurrent liquid-liquid extraction with a Tertiary amine in kerosine was used to separate zirconium from a dilute h2so4 solution containing hafnium and other impurities. Process steps described include extraction from an aqueous feed solution to form a hafnium-contaminated, zirconium-bearing organic-phase solution, scrubbing to separate zirconium from coextracted hafnium, stripping to transfer hafnium-free zirconium into an aqueous strip liquor, chloride-loading to produce a chloride-bearing organic solution, scrubbing with the chloride-loaded organic solution to remove traces of uranium impurity from the zirconium-bearing strip liquor, and regeneration to prepare the organic solution for reuse. These steps were performed simultaneously in steady-state, bench-scale experiments. Zirconium recovery of up to 93 pct was achieved. Results of an economic evaluation are included.
IH; Report of Investigations
Page last reviewed: May 5, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division