recycling of precious metals from e-scrap

recovery of gold and other valuable metals from electronic scrap involves a complex metallurgical flow sheet and requires state-of-the-art recovery technologies that are available in large-scale, integrated smelter and refinery operations. at the end of their use, electronic and other electrical product scrap offer an important recycling potential for the secondary supply of gold and silver into the market. with gold concentrations reaching 200-250 g/t for computer circuit boards, this scrap is an ‘urban mine’ that is significantly richer in gold than the sources of the primary ores today. this paper gives methods of gold and silver recovery from printed circular board.  the methods of purification are given and they separate gold from the impurities (tin, copper and nickel). the obtained gold and silver have 99.99% quality.