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What are anode slimes in copper electrorefining?
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copper processing
Molten copper being made into plates.
In the process of copper electrorefining, anode slimes are the insoluble impurities that settle at the bottom of the electrolytic cell.12
During electrolytic refining, copper anodes are dissolved into an electrolytic solution, allowing pure copper to deposit onto the cathode. Because these impurities do not dissolve, they accumulate as a sludge or slime. These slimes are highly valuable because they contain concentrated amounts of precious metals—such as silver, gold, and platinum-group metals—that were present in the original copper concentrate. Once collected, these slimes undergo further processing to recover these metals.213