Separation of Silver from Liquid Media

47

Ag


Mining & Plating

Ion exchange resins are not heavily employed in the conventional mining of silver. The cost to recover the metal from the resin is often not economical considering the current market value of silver. Some smaller gold and platinum facilities employing strongly acidic leach techniques, however, use ion exchange resins to capture ionic silver. Under these conditions of an acidic stream combined with a strong brine, silver forms anionic complexes that can be captured with a strong base anion resin such as DOWEX™ 21K XLT Resin. Additional information about the recovery of precious metals from acidic halogen leach solutions can be provided by contacting Dow.

Trace Contaminant Removal

Ion exchange resins are commonly used to remove trace contaminants, including silver. In these applications, recovery is not usually desired, so the resin is treated as a disposable media (according to local regulations). Various cations have different affinities for strong acid cation exchange resins, such as DOWEX™ G 26 (H) Resin.

If the ionic matrix of the stream causes insufficient capture of silver on a strong acid cation resin, a more selective chelating resin like DOW™ XUS 43600.00 Developmental Thiouronium Resin should be considered instead.

NOTICE: If products, such as DOW™ XUS products, are described as “experimental” or “developmental”: (1) product specifications may not be fully determined; (2) analysis of hazards and caution in handling and use are required; (3) there is greater potential for Dow to change specifications and/or discontinue production; and (4) although Dow may from time to time provide samples of such products, Dow is not obligated to supply or otherwise commercialize such products for any use or application whatsoever.