| 摘要 |
<p>Granular niobic oxide for use in the adsorption of plutonium from solution (see Group XL(a)) is prepared (a) by sintering powdered niobic oxide at 1100 DEG -1300 DEG C. and grinding the product; (b) by oxidising niobium metal of the required particle size in air at about 875 DEG C.; or (c) by dissolving niobium metal in a mixture of hydrogen fluoride and nitric acid and adding ammonium hydroxide to precipitate the hydrated oxide, which is removed, dried at 100 DEG C., and crushed to the required size.</p> |
