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How is uranium extracted from uranium ore?

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Enrichment of uranium — uranium processing How uranium is enriched to make a nuclear weapon.

Uranium is extracted from ore using hydrometallurgical processes, as traditional smelting and physical concentration methods are generally ineffective for uranium ores.1

Leaching

After the ore is crushed, the uranium is extracted through leaching, which requires the uranium to be in a hexavalent state.23
* Acid Leaching: Commonly uses sulfuric acid to dissolve the uranium, often requiring an oxidant like manganese dioxide or sodium chlorate to convert tetravalent uranium to the hexavalent state.2
* Alkaline Leaching: Used for ores containing basic minerals like calcite or dolomite, employing sodium carbonate solutions and oxygen as an oxidant.2

Precipitation and Refining

Following clarification of the leach liquor, the uranium is precipitated to form a concentrate known as yellow cake.24
* Precipitation: From acidic solutions, uranium is typically precipitated as ammonium diuranate using ammonia; from alkaline solutions, it is often precipitated as sodium diuranate using sodium hydroxide.4
* Final Purification: The yellow cake is dissolved in nitric acid and refined via a tributyl phosphate solvent-extraction process to achieve nuclear-grade specifications.5