Why does copper move from the anode to the cathode during electrorefining?

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Molten copper pours from a large industrial furnace into rectangular molds at a copper smelting facility, with glowing metal and industrial equipment visible. — copper processing Molten copper being made into plates.

During the process of electrorefining, copper moves from the anode to the cathode because of the application of a direct current to the electrolytic cell.2

When the copper anode and a starting sheet (the cathode) are immersed in an electrolyte solution—typically composed of copper sulfate and sulfuric acid—the electric current causes the copper at the positively charged anode to dissolve into the solution as ions. These copper ions then migrate through the solution and are deposited in a pure form onto the negatively charged cathode. This electrochemical process effectively separates the copper from impurities, which either remain in the solution or settle at the bottom of the cell as anode slimes.12