Editors: | Kongoli F, Fehrmann R, Gadzuric S, Gong W, Seddon KR, Malyshev V, Iwata S |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2017 |
Pages: | 151 pages |
ISBN: | 978-1-987820-65-2 |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
Waste electric and electronic equipment (WEEE) are an important secondary source of rare and precious metals and their processing through ecological technologies constitutes a major concern in the European Union and contributes significantly to the reduction of environmental pollution and to the preservation of valuable resources of precious metals.
The present work describes the application of ionic liquids (ILs) to selective dissolution and recovery of Au and Ag from the anodic slime obtained by a triple anodic dissolution of cast WEEE. The ionic liquid used (DES type) was choline chloride-ethylene glycol (molar ratio 1:2) at room temperature (250C) and iodine (in a concentration of 0.2 mol dm1) was used as a catalytic agent. The deposition potentials for Au and Ag were determined by cyclic voltammetry. By anodic dissolution and electrodeposition from the cast WEEE we obtained black gold and gray silver deposits. The SEM and EDX analyses reveal that cathodic deposition of >98% for both Au and Ag. This work demonstrates that ILs could be a solution to the selective recovery of precious metals from WEEE.