Separation of Cobalt from Liquid Media
Cobalt is generally found as the multi-valent cation, Co+, and less often as the mono-valent ion, Co+. Both ionic forms can generally be sorbed by strong or weak acid cation exchange resins. For the more demanding applications, chelating resins from DuPont may offer significant benefits.
DuPont has developed multiple resin products to refine cobalt, depending on the separation need:
Extraction of cobalt and nickel is achieved with AmberSep™ M4195 UPS Developmental Chelating Resin; a two-stage elution then separates the cobalt from nickel.
Separation of cobalt from zinc is accomplished with AmberLite™ IRC747 Chelating Resin.
Today, AmberSep™ M4195 Chelating Resin is used to facilitate the difficult separation of nickel from cobalt in cobalt refining facilities with examples in a nickel refinery in Ontario, Canada and a cobalt refinery in Zambia, Africa. The Zambian refinery is designed to produce between 2,000 and 4,000 tons of cobalt and more than 5,000 tons of copper per year from the slag dumps. See the references below for details on the use of AmberSep™ M4195 Chelating Resin in the refining of cobalt.
Cobalt is often a problem metal in precious metal and trivalent chromium plating operations. The distinct ability of AmberSep™ M4195 UPS Developmental Chelating Resin to selectively sorb Co+ from strongly acidic media makes it perfect for many acidic plating baths and for bright-dip rinse applications in aluminum finishing processes. AmberSep™ M4195 UPS Resin offers superior kinetics due to its uniform particle size distribution. In systems requiring lowest pressure drop, AmberSep™ M4195 Chelating Resin will be preferred.
In some solutions of hydrochloric acid, cobalt forms anionic complexes that can be captured using a strong base anion exchange resin like AmberSep™ 21K XLT Resin.
Removal of cobalt from water and organic solvents is fairly common using strong acid cation resins. For waters with low levels of salt content, a strong acid cation resin such as AmberSep™ G26 H Resin would be a good starting point. In addition, weakly acidic cation exchange resins like AmberLite™ IRC83 H Resin are often quite selective for multivalent ions such as Co+.
If the wastewater is highly acidic, AmberSep™ M4195 Chelating Resin is recommended.
“Development of an ion exchange process to recover cobalt and nickel from primary lead smelter residues” by Kennedy, D. C.; Becker, A., III; Worcester, A., A., Conference: Metals Specification, Separation, and Recovery, Chicago, Illinois, USA, 27 July -1 August, 1986, Lewis Publishers, Inc., 121 South Main St., PO Drawer 519, Chelsea, Michigan, 48118, USA, 1987.
“Cobalt recovery from copper leach solutions” by Jeffers, T. H.; Harvey, M. R., Report, Rep. Invest. - US, Bur. Mines (1985), RI 8927, 16 pp.
“Separation and recovery of cobalt from copper leach solutions” by Jeffers, T. H., Journal, J. Met. (1985), 37(1), 47-50.
“Separation of nickel from cobalt in sulfate medium by ion exchange” by Rosato, L.; Harris, G. B.; Stanley, R. W., Hydrometallurgy (1984), 13(1), 33-44.
“Selective absorption of copper, nickel, cobalt and other transition metal ions from sulfuric acid solutions with the chelating ion exchange resin XFS 4195” by Grinstead, Robert R., Patent US 4451375 A 840529, US 83-526303 830825, The Dow Chemical Company, USA, 3 pp.
“Ammoniacal elution of copper from ion exchange resins” by Byleveld, Eduard, Patent US 4371506 A 830201, US 81-274865 810618, Himsley Engineering Ltd., Can. US, 8 pp.
NOTICE: If products, such as DUPONT™ 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 DuPont to change specifications and/or discontinue production; and (4) although DuPont may from time to time provide samples of such products, DuPont is not obligated to supply or otherwise commercialize such products for any use or application whatsoever.