Crude copper (containing 99% copper) is made into a thick plate as the anode, pure copper is made into a thin sheet as the cathode, and a mixture of sulfuric acid and copper sulfate is used as the electrolyte. After energized, copper from the anode dissolved into copper ions (Cu) to the cathode to move to the cathode, after arriving at the cathode to obtain the electrons and precipitate pure copper at the cathode (also known as electrolytic copper). Crude copper impurities such as iron and zinc, which are more active than copper, are dissolved into ions (Zn and Fe) along with copper. Because these ions are not easy to precipitate compared with copper ions, so electrolysis as long as the appropriate adjustment of the potential difference can be avoided in the cathode precipitation of these ions. Than copper inactive impurities such as gold and silver deposited at the bottom of the electrolyzer. The copper sheet produced in this way is called “electrolytic copper” and is of such high quality that it can be used to make electrical products.
No.1 electrolytic copper is the standard copper cathode. National standard GB/T467-1997 standard cathode copper, copper and silver content of not less than 99.95%. 1 electrolytic copper copper (bright copper): China’s national standard GB5231: No. 1 electrolytic copper copper, (copper + silver) content of the minimum value of 99.95%; No. 2 electrolytic copper, (copper + silver) content of the minimum value of 99.90%. According to the provisions of the delivery system of the Shanghai Futures Exchange, the registered copper is divided into standard products and substitutes for two different delivery levels.
