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Why is fire-refined copper cast into anodes?
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copper processing
Molten copper being made into plates.
Fire-refined copper is cast into anodes to prepare it for the final stage of purification: electrorefining.
After fire refining, the copper reaches a purity level of approximately 99.5 percent, which is the standard required for the electrolytic process. By casting the metal into the specific shape and weight of an anode, it can be properly immersed in an electrolytic cell alongside cathode starter sheets. During this process, an electric current is applied to dissolve the copper from the anode and deposit it in a highly pure form—exceeding 99.9 percent purity—onto the cathode, while remaining impurities and precious metals settle as anode slimes for recovery.12