| 20100167077 | PROCESS FOR PRODUCING PURE METALLIC INDIUM FROM ZINC OXIDE AND/OR SOLUTION CONTAINING THE METAL - This invention is intended to provide an innovative process to produce pure metallic indium with the use of sulphured concentrates of zinc and lead as sources of the metal. The process begins with the zinc oxide produced by Waelz process from the neutral leaching residues of the zinc oxide calcinate. But the overflow (or supernatant) of the mild leaching of neutral underflow (or residue) of neutral leaching of zinc calcinate also contains indium in lower proportion and may or may not be part of the global process of indium recovery. The new technology is characterized by comprising the following stages: a) Production of indium pre-concentrate; b) Production of indium cement: comprised, in turn, of at least a mild leaching and at least one strong leaching of the indium cement product obtained in the reducing leaching; c) Production of indium solution; d) Extraction of indium by organic solvent; e) Cementation of indium; f) Fusion, purification, and ingoting of the metal; g) Electrolysis of indium to obtain a product with high purity more than 99.995%. | 07-01-2010 |
