Method for the Recovery of Indium from Diluted Bioleaching Solutions

Abstract

Using a commercially available solvent impregnated resin, Lewatit TP272, in an ion exchange process, it was possible to extract up to 90 % indium from a feed containing as little as 1 mg/L indium in the presence of high amounts of impurities, i.e. 1000 mg/L iron and zinc each. It was demonstrated that through gradient regeneration of obtained loaded ion-exchange resin, it is possible to yield a solution containing as much as 400 mg/L indium along with 400 mg/L iron, thereby upgrading its purity more than 600 times. Moreover, it was shown that this solution can be fed into an existing solvent extraction procedure which would yield an indium oxide with more than 99 % purity.

Separation of Indium from Acid Sulfate‐Containing Solutions by Ion Exchange with Impregnated Resins

“…4, > 90 % of the contained indium was extracted at 117 BV. As acidic extractants, such as D2EHPA and Cyanex 272, exhibit a relatively high affinity for zinc, the column was eluted with 0.1 mol L -1 sulfuric acid prior to the elution with HCl [18,23,24].…”

“…This fact is due to their extraction mechanisms in which protons are involved. However, lower concentration of the re-extractant solution is required when Cyanex 272 is used for the extraction [19,24]. Furthermore, it can thus be assumed without doubt that the elution will also show a more favorable profile compared to the elution from the D2EHPA-impregnated resin.…”

Quantifying indium with ion chromatography in hydro‐ and biohydrometallurgical leaching solutions

“…Typically, dissolution of raw materials via (bio)hydrometallurgical methods is non‐specific, resulting in leachates containing high concentrations of zinc and iron, and comparatively low concentrations of the target metals such as indium. However, a variety of methods exist to concentrate indium in solution , the aim is to reach concentrations at which solvent extraction becomes a realistic commercial process (1 to 10 mg/L) . Solution quantification is essential for tailoring these subsequent extraction processes .…”