| 摘要 |
<p>Metal salts are recovered from aqueous solutions thereof by forming complexes with N-oxides of alkyl substituted pyridines in which the total carbon content of the alkyl groups present is at least 4. The process may be adapted to the selective recovery of a particular metal salt from a mixture of metal salts. Aqueous solutions formed directly from a natural ore containing a particular metal may be treated to obtain a particular salt of said metal, usually the nitrate. The process is particularly adapted to the recovery of salts of uranium, thorium, zirconium, mercury and bismuth. The precipitated complexes may be purified by recrystallization from water.ALSO:The invention comprises N-oxides of pyridine substituted by at least 4 alkyl radicals, the number of carbon atoms contained in the said alkyl radicals taken together being 5 or more. The N-oxides are obtained from the corresponding alkyl pyridines by oxidation with H2O2, and are used for complexing metal salts such as uranyl or thorium nitrates.</p> |
