Copper purification through electrolysis involves the passage of an electric current through a solution of copper salts, which leads to the deposition of copper ions onto a cathode.

In this electrolysis process, an impure copper rod serves as the anode (the electrode where oxidation occurs), while a pure copper rod functions as the cathode (the electrode where reduction takes place). The electrolyte solution used is typically a copper sulfate solution, which is rich in copper ions.

When the electric current is introduced into the solution, copper ions from the impure copper anode undergo oxidation and dissolve into the solution. These dissolved copper ions are then attracted to the cathode, where they gain electrons and are reduced to form pure copper atoms. Consequently, these pure copper atoms deposit onto the cathode, gradually creating a layer of high-purity copper.

The impurities present in the anode, such as precious metals like gold and silver, do not dissolve into the solution. Instead, they settle at the bottom of the electrolysis cell, forming a sludge. This sludge can be collected and processed to recover these valuable metals.

The electrolysis process continues until all the impure copper from the anode has been transferred to the cathode. The end result is a pure copper cathode and an electrolyte solution that is depleted of copper ions. This method is highly effective, achieving a very high degree of copper purity.

In summary, electrolysis is a powerful technique for copper purification. It leverages the principles of oxidation and reduction to selectively transfer copper ions from an impure anode to a pure cathode, effectively leaving behind impurities and resulting in highly pure copper.