Electroplating is the use of chemical and electrochemical methods to deposit various metals onto the surface of metals or other materials. Electroplating technology is widely used in industries such as machine manufacturing, light industry, and electronics.

The composition of electroplating wastewater is very complex. In addition to cyanide (CN -) wastewater and acid-base wastewater, heavy metal wastewater is a potentially hazardous type of wastewater in the electroplating industry. According to the classification of heavy metal elements in heavy metal wastewater, it can generally be divided into chromium (Cr) wastewater, nickel (Ni) wastewater, cadmium (Cd) wastewater, copper (Cu) wastewater, zinc (Zn) wastewater, gold (Au) wastewater, silver (Ag) wastewater, etc. The treatment of electroplating wastewater is widely valued both domestically and internationally, and various treatment technologies have been developed to eliminate and reduce heavy metal emissions through measures such as transforming toxic to non-toxic, harmful to harmless, recycling precious metals, and water recycling. With the rapid development of the electroplating industry and the increasing demand for environmental protection, the treatment of electroplating wastewater has begun to enter the stage of clean production technology, total quantity control, and integration of circular economy. Resource recycling and closed-loop circulation are the mainstream directions of development.