PROCESS FOR RECOVERING PRECIOUS METALS FROM ELECTRICAL AND ELECTRONIC WASTE BY ANODIC DISSOLUTION IN IONIC LIQUIDS

摘要

The invention relates to a process for recovering usual metals such as Cu, Sn, Pb, Al and Ni and precious metals, Au and Ag, comprised in waste electrical and electronic equipments, such as PCs, mobile phones, audio-video apparatuses, automation equipments and the like. According to the invention, the process comprises the following stages: a. processing the waste by milling, melting in microwave oven, separating the organic fraction which represents 45...50% of waste, casting them as a multicomponent metal ingot with the following chemical composition: 45...50% Cu, 15...25% Sn, 12...18% Pb, 2..4% Al, 0.5...1.5% Fe, 0.5...1% Ag, 0.1...0.2% Au and 0.5...1.5 % other elements, b. anodically dissolving the ingot in a electrolyte based on HSO-CuSOwhile recovering Cu or Cu-Sn alloy at the cathode and concentrating insoluble metals in the electrolyte as anodic mud, c. melting the resulting anodic mud and casting it as an ingot, d. selectively anodically dissolving the anodic mud ingot, melt in an electrolyte based on ionic liquids, consisting of a mixture of organic choline chloride salts and ethylene glycol which form an eutectic mixture, the anodic dissolution taking place in a glass vessel at a temperature ranging between 20...25°C by using a Cu cathode, Ag of a purity of 99.5% at a cell voltage of 0.1...0.25 V at the cathode there being obtained, as well as Au of a purity of 99% at a cell voltage of 0.4...0.5 V.