Bis(formato-O)dioxouranium → HCID 20465779, compound

Temperature

25 °C

Unsaturated uranyl formate solution from the denitration step and at the denitration temperature of about 90° C. is then contacted with additional formic acid to precipitate uranyl formate monohydrate. The formic acid is added in sufficient stoichiometric excess and at a rate selected to control the nucleation and growth of crystalline particles during precipitation and to yield the desired particle size distribution for powder metallurgical requirements. Formic acid preferably at or in excess of 19.9 M concentration is added at a rate of between about 0.40 and 1.27 moles/(min)(liter of uranyl nitrate feed) to raise the solution acid concentration from about 0.3 to about 1.4 moles/100 g of solution. A higher concentration of formic acid (about 1.6 to 1.7 moles/100 g solution) is achieved by conventional volume reduction (evaporation) and controlled addition of small quantities of 90% formic acid. At this concentration the solution and precipitate are cooled to ambient room temperature (about 25° C.). The precipitate is then recovered by filtration. The precipitate is washed during this step with 90% formic acid to remove residual contaminants. The filter cake, consisting essentially of substantially pure uranyl formate monohydrate (UO2 (HCOO)2.H2O), is then dried at 110° to 120° C. for one to four hours to provide a crystalline uranyl formate monohydrate salt.

1. customat the denitration temperature of about 90° C.
2. customto precipitate uranyl formate monohydrate
3. additionThe formic acid is added in sufficient stoichiometric excess and at a rate
4. customduring precipitation
5. customto yield the desired particle size distribution for powder metallurgical requirements
6. concentrationFormic acid preferably at or in excess of 19.9 M concentration
7. additionis added at a rate of between about 0.40 and 1.27 moles/(min)(liter of uranyl nitrate feed)
8. temperatureto raise
9. concentrationthe solution acid concentration from about 0.3 to about 1.4 moles/100 g of solution
10. concentrationAt this concentration the solution and precipitate
11. filtrationThe precipitate is then recovered by filtration
12. washThe precipitate is washed during this step with 90% formic acid
13. customto remove residual contaminants
14. customis then dried at 110° to 120° C. for one to four hours

ORD record

ord-fce53c8a39584b4f873c5db58ebe74d2

Source dataset

uspto-grants-1980_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04201738