Separation and recovery of molybdenum values from uranium process waste
US4584184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1984 |
| Grant date | Apr 22, 1986 |
| Priority date | — |
| Expiry date | May 21, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for treating process waste consisting of uranium hexafluoride, UF.sub.6, molybdenum hexafluoride, MoF.sub.6 and molybdenum oxytetrafluoride, MoOF.sub.4 is provided wherein the foregoing mixture is hydrolyzed in an aqueous solution of ammonium carbonate and ammonium hydroxide. The resulting mother liquor is digested at 60.degree.-80.degree. C. to drive off carbon dioxide and convert the ammonium uranyl carbonate, (NH.sub.4).sub.4 UO.sub.2 (CO.sub.3).sub.3 to ammonium diuranate, (NH.sub.4).sub.2 U.sub.2 O.sub.7. The pH is maintained above 9 to prevent premature precipitation of the molybdenum values as molybdic acid or uranyl molybdate. The ammonium diuranate which forms as a yellow solid is filtered, slurried in aqueous ammonium hydroxide, filtered and dried. The yield is quantitative. Pyrolysis results in conversion of the diuranate salt to uranium oxide, U.sub.3 O.sub.8, of suitable purity to be recycled in the uranium hexafluoride production process. The combined filtrates which contain the molybdenum values and ammonium fluoride by-product are diluted, and stirred, with 95% ethanol to precipitate white, crystalline, ammonium molybdate, (NH.sub.4).sub.2 MoO.sub.4. The am…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.