Electrolytic purification of copper: Coarse copper (containing 99% copper) is pre made into thick plates as the anode, pure copper is made into thin plates as the cathode, and a mixture of sulfuric acid (H2SO4) and copper sulfate (CuSO4) is used as the electrolyte. After being electrified, copper dissolves from the anode into copper ions (Cu) and moves towards the cathode, After reaching the cathode, electrons are obtained and pure copper (also known as electrolytic copper) is precipitated at the cathode. Impurities such as iron and zinc, which are more active than copper, dissolve together with copper to form ions (Zn and Fe). As these ions are less likely to precipitate compared to copper ions, adjusting the potential difference appropriately during electrolysis can prevent these ions from precipitation at the anode. Impurities such as gold and silver, which are less active than copper, deposit at the bottom of the electrolytic cell

The copper plate produced in this way is called "electrolytic copper" and has extremely high quality, which can be used to make electrical products.

The sediment at the bottom of the electrolytic cell is called "anode mud", which is rich in gold and silver and is very valuable. It has extremely high economic value when taken out and processed

Electrolytic copper=cathode copper