DOWEX Resins for Separation of Gold from Liquid Media

Gold - Au Gold mining operations are improving their economics out of financial necessity and innovations in gold hydrometallurgy are emerging on a regular basis as operations trim down. Dow has long been at the forefront of many of these new developments with the commercial use of Dow's ion exchange resins in the primary recovery of gold in mining operations.

Applications

Cyanidation Mining: Gold recovery from mining cyanidation leach solutions with anion exchange resins has long been common practice in the gold mines of the former Soviet Union (FSU). Today Western mining companies are discovering the economic benefits of gold recovery via ion exchange resins.

Dow produces a gold selective resin, specifically designed for use in resin-in-pulp and pump-cell processing. The resin is XZ 91419.00** developmental resin, manufactured under exclusive license from South Africa's premier mining technology house, MINTEK. New process development using XZ 91419.00 resin can be fully supported through contractual arrangement with MINTEK's expert technical staff. For information on who to contact about the use of XZ 91419.00 resin in gold mining applications, e-mail Dr. Charles Marston at cmarston@dow.com.

Acidic Halogen Leach: Many developmental projects are also underway where ores are leached under oxidizing and acidic conditions. Here, too, DOWEX™ anion exchange resins have proven to be tough, steady performers. Additional downloadable information is available in Recovery of Precious Metals from Acidic Halogen Leach Solutions (364KB PDF).

Copper/Gold: Additionally, several companies have proposed cyanide recovery techniques using anion exchange resins. Notably, AuGment (JV between EI DuPont and Newmont Mining), Tallon Metal Technologies (VitrokeleTM chemistry), and MINTEK have brought processes to the marketplace. Efficient cyanide recovery processes could open the way for the use of cyanide on cyanide consuming ores like gold porphyries (Au/Cu). New cyanide recovery resins are under development. Please contact us if you have an interest in exploring this technology. Full scale commercial operation of an ion exchange based cyanide recovery process for copper/gold ore, is currently pending.

Plating Baths: DOWEX anion exchange resins are commonly used in the recovery of gold from spent plating bath solutions. Generally, the loaded resin will absorb up to 60 oz of gold per cubic foot of resin (60g/l resin) and the gold is recovered by thermal decomposition (fuming). Downloadable information on fuming is available in Recovery of Precious Metals from Acidic Halogen Leach Solutions (364KB PDF).

DOWEX Ion Exchange Resins

Product	Description	Type	Matrix	Total Exchange Capacity* eq/l (kgr/ft3)	Available Forms
DOWEX 21K XLT	Uniform particle size, high capacity, strong base anion exchange resin for mineral processing applications.	Type I Strong Base Anion	Styrene-DVB, Gel	1.4	Cl-
DOWEX 21K 16/20	High efficiency, strong base anion exchange resin for mineral processing applications.	Type I Strong Base Anion	Styrene-DVB, Gel	1.2	Cl-
DOWEX 21K 16/30	High efficiency, strong base anion exchange resin for mineral processing applications.	Type I Strong Base Anion	Styrene-DVB, Gel	1.2	Cl-
XZ 91419.00**	A large bead, gold selective strong base anion exchange resin for the recovery of gold from cyanidation leach solutions (manufactured under license from MINTEK)	t-Butylamine	Styrene-DVB, Gel	0.23 - 0.33 eq/l	Cl-
DOWEX M-43	Corrosion control with DOWEX M-43 ion exchange resin.	Weak Base Anion	Styrene-DVB, Macroporous	1.55	FB (Free Base) form

** Notice: For products that are "developmental", i.e. have an EB, XUS, XY or XZ number: (1) quality specifications may not be fully determined; (2) hazards may not be fully known, and additional caution in handling and use is required; and (3) Seller reserves the right to change specifications and/or discontinue its sale. Users are cautioned to confirm opinions, findings and data by their tests and to satisfy themselves as to the suitability of such products for the purposes intended prior to use.