INDIUM RECOVERY FROM INDUSTRIAL ZINC RESIDUES

摘要

This work presents a study of indium recovery from sulphuric liquor generated during the hydrometallurgical processing of zinc. The investigation aims at defining a process to obtain a purified solution of the metal fitting industrial requirements for further use. The main steps of the process were studied. Indium was initially precipitated with a small amount of iron to generate a solution with a lower Fe/In ratio. Following that the solution was fed into the solvent extraction experimental unit for the recovery of indium, which was subsequently purified. A study of the main parameters of the process was conducted for the steps: iron reduction, indium precipitation, precipitate solubilization, solvent extraction and stripping of indium. The experimental results indicated that it was possible to obtain aqueous indium solutions with a high grade of purity. The recovery was practically complete: over 98%.