Briefly explain eletro refining process for extraction of cu
Answers
In the electrolytic refining of copper, the impure copper is made from the anode in an electrolyte bath of copper sulfate, CuSO4, and sulfuric acid H2SO4. The cathode is a sheet of very pure copper. As current is passed through the solution, positive copper ions, Cu2+, in the solution are attracted to the negative cathode, where they take on electrons and deposit themselves as neutral copper atoms, thereby building up more and more pure copper on the cathode. Meanwhile, copper atoms in the positive anode give up electrons and dissolve into the electrolyte solution as copper ions. But the impurities in the anode do not go into solution because silver, gold and platinum atoms are not as easily oxidized (converted into positive ions) as copper is. So the silver, gold and platinum simply fall from the anode to the bottom of the tank, where they can be scraped up.