| 摘要 |
<p>Rhodium is recovered from an acid solution containing nuclear fission products by treating the solution to precipitate insoluble sulphides and then separating rhodium from the precipitate. A nitric acid solution of fission products may be treated with hydrochloric acid and evaporated several times to remove nitric acid, followed by precipitation of sulphides with hydrogen sulphide from the hydrochloric acid solution. The precipitate is dissolved in aqua regia, the rhodium converted to Na3Rh (NO2)6 by addition of NaNO2, and the solution made alkaline to precipitate impurities which are removed. The solution is heated with hydrochloric acid, ruthenium and other volatile fission products removed by distillation (as described in Specification 941,985), and then the rhodium reduced to metal with iron, magnesium, aluminium, zinc, or formate ion. The metal is heated in chlorine to form insoluble RhCl3 which is reduced in hydrogen to the metal.</p> |
