Extraction of selenium from gold bearing stone

Some gold ores contain selenium, such as copper, silver, lead, nickel, and gold. Studies by Ian Praksyn, Ann Suvarovsky and Av Astafieva have shown that the presence of selenium makes it difficult to extract gold from ore - cyanide, because it also dissolves, and in the subsequent process, the zinc dust is surrounded by zinc, reducing gold production.
The authors have developed a process to extract selenium from ore before it is cyanated. To this end, crushed stone was treated by induction or injection with a chlorinated lime solution Ca(OCl)Cl. When selenium is oxidized to selenic acid, for example, by an approximate simplified reaction:
Now 3cl + splashing over 2H2O = H2SeO3 + 3ccl2 + Me(OH2).

When selenium is decomposed into a solution, the selenium is extracted into the solution by releasing the selenium solution into the carbon dioxide in the solution or into the cement in the metal.



 

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