Electrofiining

Electrofiining is a process used to purify metals, most commonly copper, through electrolysis. It is an electrolytic refining technique where the impure metal is used as the anode and a thin sheet of the pure metal serves as the cathode. The electrolyte is a solution containing ions of the metal being refined, such as copper sulfate.

During electrofiining, an electric current is passed through the cell. The impure anode dissolves, with the desired metal ions migrating towards the cathode. At the cathode, these metal ions are reduced and deposit as a pure layer of the metal. Impurities that are more noble than the anode metal fall to the bottom of the cell as anode sludge, which can be a valuable source of precious metals like gold and silver. Less noble impurities remain dissolved in the electrolyte.

The primary advantage of electrofiining is its ability to produce extremely high purity metals, often exceeding 99.99%. This purity is crucial for applications in electronics, electrical wiring, and other industries where conductivity and performance are paramount. The process is also relatively energy-efficient compared to other refining methods. While copper is the most common metal refined this way, electrofiining can also be applied to other metals like silver, gold, and nickel, though the specific electrolytes and conditions may vary. The control over the process allows for the production of metal with very specific and consistent quality.