摘要 |
Uranium concentrate contg. zirconium and/or hafnium impurities is purified by (a) suspending the concentrate in an aq. medium; (b) slowly acidifying the suspension in a controlled manner; (c) treating with hydrogen peroxide to ppte. the uranium and almost all of the zirconium and/or hafnium; (d) sepg. the ppte. and treating it with an acid to solubilise the uranium as uranyl ions; and (e) sepg. the uranyl soln. from the solid phase contg. the zirconium and/or hafnium. The process gives an uranium liquor of improved purity by eliminating all impurities except Zr and/or Hf in a first leaching and pptn. stage (steps a-c) and then eliminating the Zr and/or Hf in a second uranium leaching stage (steps d and e). |