Study on Leaching of Gold from Abandoned Circuit Board
Author of the article:SHI Kaiyi;ZHANG Lingfeng;DING Weili
Author's Workplace：Department of Chemistry and Materials Engineering, Liupanshui Normal University, Liupanshui 553004,China;Characteristic Key Laboratory of Coal Series Solid Waste Recycling Utilization,Liupanshui 553004,China
Key Words：e-waste leaching precious metal gold
Abstract：
In order to recover the precious metal gold in the electronic waste, the waste circuit board was firstly broken and burned to get the ash residue, and the gold and other elements in the ash residue were determined by atomic absorption method. Then hydrochloric acid and nitric acid were used to dissolve the base metal in the ash residue, and hydrochloric acid and sodium chlorate were used to dissolve the gold. Finally, the powder gold was analyzed by X-ray photoelectric spectroscopy. The results show that the average contents of gold, lead, cadmium and chromium in the board slag are 0.0972, 5.1649, 0.0039 and 0.099 7 mg/g, respectively. The higher the concentration of hydrochloric acid and sodium chlorate,the higher the extraction rate of gold. When the concentration of hydrochloric acid and sodium chlorate is 3.0 mol/L and 12 g/L respectively, the extraction rate of gold powder is 71.40%. Powder gold contains a large amount of pure gold and a small amount of impurities mainly SiO2.
