types of thiosulfate leaching of gold from ores

 

The leaching and adsorption of gold using low

Jan 01, 2015· ABSTRACTThis literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent progress on thiosulfate leaching of gold, as well as the production, oxidation, and stabilization of thiosulfate. The leaching results of different types of gold ores including oxide

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A Review of Ammoniacal Thiosulfate Leaching of Gold: An

ABSTRACTThis literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent progress on thiosulfate leaching of gold, as well as the production, oxidation, and stabilization of thiosulfate. The leaching results of different types of gold ores including oxide, sulfide, carbonaceous, and refractory ores/concentrates

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types of thiosulfate leaching of gold from ores

Sodium Thiosulphate Gold LeachingSodium Thiosulphate Gold Leaching The gold industry has been seeking alternative reagents for leaching gold from lowg

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Thiosulfate Leaching Thiosulfate leaching is an alkaline

Mar 17, 2019· Thiosulfate Leaching Thiosulfate leaching is an alkaline process which removes gold from carbonaceous ores instead of using cyanide. It is less destructive and toxic, and has a higher efficiency with preg robbing ores as a leaching agent. The majorponents of thiosulfatemon fertilisers which include ammonium thiosulphate and ammonium sulphate.

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GOLD LECHING FROM A SAUDI ORE BY THE NONPOLLUTING

thiosulfate leaching of gold Chen, 2008. This shows how much a mineralogical investigation is important to be performed before leaching study of any gold ore by the thiosulfate process. Several gold localities are scattered in the Arabian Shield of the kingdom of Saudi Arabia which has about 20 million tons of recoverable gold ores.

More

Barrick Thiosulfate Leaching of Double Refractory Ore

the ore, but autoclaves cannot autoclaves can only remove the sulfides. The thiosulfateplex formed in thiosulfate leaching is not attracted to carbon so this failure to remove the carbon is no longer an issue. Thus, the use of thiosulfate with autoclave processed double

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Thiosulfate leaching of goldA review ScienceDirect

Thiosulfate leaching can be considered a non toxic process, the gold dissolution rates can be faster than conventional cyanidation and, due to the decreased interference of foreign cations, high gold recoveries can be obtained from the thiosulfate leachingplex and carbonaceous type ores. In addition, thiosulfate can be cheaper than cyanide.

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Thiosulfate leaching of gold A review Request PDF

The application to different ore types and process options have also been discussed.The thiosulfate leaching process it catalysed by copper and has several advantages over the conventional

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THIOSULPHATE LEACHING

alternative to cyanidation for some gold bearing ore bodies. Whether the leaching is performed in stirred tank reactors or heaps, the size and type of equipment needed for a thiosulphate leaching flowsheet is very similar to a conventional cyanide leach. SGS is a global technical leader in the field of thiosulphate leaching, and our

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Gold strike with thiosulphate

Within the tanks, the slurry interacts with thiosulfate and a fine, bead like material called resin that collects the gold. At full capacity, 13,400 tons of ore can be processed daily, with

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Using Nickel as a Catalyst in Ammonium Thiosulfate

Using Nickel as a Catalyst in Ammonium Thiosulfate Leaching for Gold Extraction On a 100mass 75mm of silicate type gold ore containing 16g/t Au and 0.2mass of Fe and C, the nickel catalyzed ammonium thiosulfate solution could extract 95 of gold with the 1.2kg/t ore of ammonium Using Nickel as a Catalyst in Ammonium Thiosulfate

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leaching of gold from copper rich ores operatoresportivo.it

leaching of gold copper ores with ammoniacal cyanide solutions. Eliminating Copper from Gold Ore. Copper minerals, even thoughponents of precious metal ores, dissolve in these cyanide leaching solutions, consume cyanide, cause fouling of mill solutions, and thus interfere with the precipitation and recovery of gold.2,3,4 Here is a summary of laboratory investigations on the use of

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Alternative lixiviants to cyanide for leaching gold ores

Despite the research interest and pilot plant trials on many of the noncyanide gold lixiviants, the majority are still at the development stage. The most advanced alternative lixiviant is thiosulfate leaching of carbonaceous preg robbing ores, which has been largely developed by Newmont Mining, Placer Dome, and Barrick Gold.

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A Method for Leaching or Dissolving Gold from Ores or

lurgical gold extraction routes utilize a leaching step to produce a gold bearing solution as an intermediate product while the recycling of secondary gold from electronic and precious metal scrap is based on the selective and fast dissolu tion of the precious metal. Therefore, A Method for Leaching or Dissolving Gold from Ores or Precious

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Gold extraction

Gold extraction refers to the processes required to extract gold from its ores.This may requirebinationminution, mineral processing, hydrometallurgical, and pyrometallurgical processes to be performed on the ore.. Gold mining from alluvium ores was once achieved by techniques associated with placer mining such as simple gold panning and sluicing, resulting in direct recovery of

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PDF Thiosulfate leaching of gold from waste mobile

M ammonia. Similar trends were obtained for the leaching of gold from two different types of scraps and PCBs of waste mobile phones. From the scrap samples, 98 of the gold was leached out using a solution containing 20. mM copper, 0.12. M thiosulfate and 0.2. The importance of controlling oxygen addition during the thiosulfate leaching of

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Barrick Thiosulfate Leaching of Double Refractory Ore

Barrick requests the Leaching Team to optimize the thiosulfate leaching process for double refractory ores. In addition, the Leaching Team analyzed the thiosulfate leachingpared to the traditional cyanide process. They found that the profit of the thiosulfate leaching process was similar to that of the traditional cyanide method.

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The effect of solution parameters on the thiosulfate

Sep 10, 2014· a. Effect of the copper concentration on the dissolution of gold in thiosulfate leaching. Solution parameters: 0.6 mol/L Sodium thiosulfate, 0.2 mol/L sodium carbonate, 0.05 mol/L sodium citrate and 0.025 mol/L EDTA at pH 10. b. Effect of the copper concentration on the thiosulfate concentration in gold leaching.

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AMMONIACAL THIOSULPHATE LEACHING OF A COPPER RICH GOLD ORE

PDF In this current study, the extraction of gold from a high grade copper rich gold ore by copper assisted ammoniacal thiosulphate leaching was studied by adopting Taguchi L 9, 3 3

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use of thiosulfate in gold leaching christoartfair.nl

The leaching results of different types of gold ores including oxide, Read More Thiosulfate leaching of gold A review Request PDF. The ammoniacal thiosulfate leaching process for gold and silver extraction has been reviewed in terms of leaching mechanism, thermodynamics, thiosulfate stability, and gold recovery options.

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leaching of gold alysts auto

The invention provides a new method for leaching gold by thiosulfate through cobalt and ammonia catalysis. The cobalt and ammonia catalysis is adopted to replace traditional copper and ammonia catalysis, that is, cobalt sulfate is added in thiosulfate gold leaching pulp to

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A Review on Alternative Gold Recovery Reagents to Cyanide

After gold content is increased by physical and mechanical methods the concentrate is used as feeding ma terial for next steps. Gold concentrates are processed by chemical methods in order torecover up to 99 gold, depending on type and efficiency of the processes . The widely used chemical treatment process is the leaching with cyanide.

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Effect of additives on thiosulfate leaching of a gold ore

Effect of additives on thiosulfate leaching of a gold ore *S.J. Dai, P.C. Li, Q.Q. Wang , D.W. Feng University of Science and Technology, Liaoning, Anshan, China Received August 15, 2017, Revised November 15, 2017 The effect of additives on gold leaching was investigated using ammonium thiosulfate or calcium thiosulfate.

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thiosulfate leaching of gold vdlinstruments.nl

Thiosulfate Leaching as an Alternative to Cyanidation by aflacglobal in Types Research Science and thiosulfate leaching as an alternative to cyanidation gold . Processes for recovering gold from copper gold ores thiosulfate leaching or gold ores copper catalyzed thiosulfate leaching using ion exchange technology are disclosed. Live Chat

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Using Nickel as a Catalyst in Ammonium Thiosulfate

Using Nickel as a Catalyst in Ammonium Thiosulfate Leaching for Gold Extraction On a 100mass 75mm of silicate type gold ore containing 16g/t Au and 0.2mass of Fe and C, the nickel catalyzed ammonium thiosulfate solution could extract 95 of gold with the 1.2kg/t ore of ammonium Using Nickel as a Catalyst in Ammonium Thiosulfate

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Associated Sulfide Minerals in Thiosulfate Leaching of

The effects of some associated minerals on thiosulfate gold leaching were studied through thermodynamic analysis and leaching experimentsposite ore samples containing various minerals and a reference silicate gold ore. In the leaching test on the reference gold ore, about 93 of gold was extracted within 3.0 hours.

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Gold leachinganic base polythionates: new non toxic

It was proposed to useanic bases as efficient gold eluting agents from an anion exchanger, after leaching with a thiosulfate Fleming et al. 2002 Matthew 2007. Thiosulfate leaching of gold represents a potentially attractive alternative to a respective cyanation process at least for three types of auriferous ores.

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US6632264B2 Gold recovery from thiosulfate leaching

Processes for recovering gold from copper gold ores thiosulfate leaching or gold ores copper catalyzed thiosulfate leaching using ion exchange technology are disclosed. The processes include subjecting the gold bearing and copper bearing thiosulfate solution to a pH and/or temperature adjustment to reduce tetrathionate concentration in the thiosulfate solution prior to contacting with an

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Associated Sulfide Minerals in Thiosulfate Leaching of

The effects of some associated minerals on thiosulfate gold leaching were studied through thermodynamic analysis and leaching experimentsposite ore samples containing various minerals and a reference silicate gold ore. In the leaching test on the reference gold ore, about 93 of gold was extracted within 3.0 hours.

More

The role of ligands and oxidants in thiosulfate leaching

The role of ligands and oxidants in thiosulfate leaching of gold Gamini Senanayake A.J. Parker Cooperative Research Centre for Hydrometallurgy, Department of Mineral Science and Extractive Metallurgy, Murdoch University, Perth, WA 6150, Australia Abstract The widely used cyanidation technology is not applicable to some gold ores due to economic or

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Copper catalyzed thiosulfate leaching of low grade gold ores.

Copper catalyzed thiosulfate leaching is being investigated by the U.S. Bureau of Mines as a potentially economical and environmentally safe method for heap leaching or in situ leaching of low grade oxidized gold ores. Six variables were investigated in fractional factorial screening tests

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The deportment of mercury during thiosulfate leaching and

Abstract. This paper reports on the behavior of mercury andpounds during the thiosulfate leaching and recovery of gold. Thiosulfate solutions are shown to dissolve Hg 0 and Hg 2 Cl 2 to a similar extent as cyanide, but the leaching of HgS is significantly slower in thiosulfatepared to cyanide. Hence, the use of thiosulfate may be an option for treating ores containing

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A review of ammoniacal thiosulfate leaching of gold: An

This literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent progress on thiosulfate leaching of gold, as well as the production, oxidation, and stabilization of thiosulfate. The leaching results of different types of gold ores including oxide, sulfide, carbonaceous, and refractory ores/concentrates and the

More

Thiosulfate Leaching of Gold from Copper Bearing Ores

Thiosulfate leaching of gold and silver has been known since 1858. In the Patera process, which was used for silver recovery for many years Lidell 1945, silver was extracted from silver chloride by sodium thiosulfate leaching of chloridizing roasted ores and concentrates.

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AMMONIUM THIOSULFATE LEACHING OF AN OXIDE GOLD

oxide gold copper ore rich in cyanide soluble copper was investigated. The main objective was to establish the efiect of the relative concentrations of the maio reagents ammonia, Cu2\ oxygen, and thiosulfate on gold extraction and thiosulfate consumption. The maximum gold extraction obtainedpatible with that

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THIOSULFATE LEACHING OF SILVER FROM A SOLID

THIOSULFATE LEACHING OF SILVER FROM A SOLID RESIDUE AFTER PRESSURE LEACHING OF PGM and gold are recovered from primary and secondary resources by means of leaching. The richest sources of these metals, being a feed for leaching, are noble metals ores, by products of nonferrous metals processing, anodic slimes from copper

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PDF Thiosulfate leaching of gold from waste mobile

M ammonia. Similar trends were obtained for the leaching of gold from two different types of scraps and PCBs of waste mobile phones. From the scrap samples, 98 of the gold was leached out using a solution containing 20. mM copper, 0.12. M thiosulfate and 0.2. The importance of controlling oxygen addition during the thiosulfate leaching of

More

Thiosulfate copper ammonia leaching of pure gold and

Dundee Sustainable Technologies, 2015 Lalancette et al., 2015. However, thiosulfate leaching of waste electrical and electronic equipment WEEE has also indicated preg robbing type behaviour Ha et al., 2010. It is not clear how different parameters and their ranges affect pure gold and gold mineral leaching in the thiosulfate media.

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Barrick Thiosulfate Leaching of Double Refractory Ore

Barrick requests the Leaching Team to optimize the thiosulfate leaching process for double refractory ores. In addition, the Leaching Team analyzed the thiosulfate leachingpared to the traditional cyanide process. They found that the profit of the thiosulfate leaching process was similar to that of the traditional cyanide method.

More

Gold leachinganic base polythionates: new non toxic

It was proposed to useanic bases as efficient gold eluting agents from an anion exchanger, after leaching with a thiosulfate Fleming et al. 2002 Matthew 2007. Thiosulfate leaching of gold represents a potentially attractive alternative to a respective cyanation process at least for three types of auriferous ores.

More

Fundamental aspects of gold leaching in thiosulfate

Theics and mechanism of gold leaching in the ammonia thiosulfate copper ATS Cu system have been studied using the rotating electrochemical quartz crystal microbalance REQCM. Anodic polarization, cathodic polarization and leaching experiments were included in this study.

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A Method for Leaching or Dissolving Gold from Ores or

lurgical gold extraction routes utilize a leaching step to produce a gold bearing solution as an intermediate product while the recycling of secondary gold from electronic and precious metal scrap is based on the selective and fast dissolu tion of the precious metal. Therefore, A Method for Leaching or Dissolving Gold from Ores or Precious

More

The role of ligands and oxidants in thiosulfate leaching

The role of ligands and oxidants in thiosulfate leaching of gold Gamini Senanayake A.J. Parker Cooperative Research Centre for Hydrometallurgy, Department of Mineral Science and Extractive Metallurgy, Murdoch University, Perth, WA 6150, Australia Abstract The widely used cyanidation technology is not applicable to some gold ores due to economic or

More

use of thiosulfate in gold leaching christoartfair.nl

The leaching results of different types of gold ores including oxide, Read More Thiosulfate leaching of gold A review Request PDF. The ammoniacal thiosulfate leaching process for gold and silver extraction has been reviewed in terms of leaching mechanism, thermodynamics, thiosulfate stability, and gold recovery options.

More

thiosulfate leaching of gold middelaartentverhuur.nl

ABSTRACTThis literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent progress on thiosulfate leaching of gold, as well as the production, oxidation, and stabilization of thiosulfate The leaching results of different types of gold ores including oxide

More

Leaching of Gold from the Waste Mobile Phone Printed

: Leaching of Gold from the Waste Mobile Phone Printed Circuit Boards PCBs with Ammonium Thiosulphate Literature reveals that only limited studies have been carried out to recover the metals from waste mobile phonePCBs. Ammonium thiosulfate is a leachant which is non toxic as well as economical. It works to stabilize gold as

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Sodium Thiosulphate Gold Leaching

The gold industry has been seeking alternative reagents for leaching gold from low grade ores for the past 25 years. The cost and transport of cyanide, the poor recovery of gold from carbonaceous ores, the lack of selectivity of cyanide towards copper minerals and the cost of waste treatment are real factors which can make cyanide unattractive in some circumstances.

More

Barrick Thiosulfate Leaching of Double Refractory Ore

the ore, but autoclaves cannot autoclaves can only remove the sulfides. The thiosulfateplex formed in thiosulfate leaching is not attracted to carbon so this failure to remove the carbon is no longer an issue. Thus, the use of thiosulfate with autoclave processed double

More

Thiosulphate Leaching Mining SGS

Thiosulfate leaching offers a number of benefits related to gold recovery yields and environmental concerns: Thiosulfate leaching of gold ores has great potential to reduce the impact on the environment. Unlike cyanide, which is highly toxic, the chemicals used in the thiosulfate leaching process are benign.

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thiosulfate leaching of gold middelaartentverhuur.nl

ABSTRACTThis literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent progress on thiosulfate leaching of gold, as well as the production, oxidation, and stabilization of thiosulfate The leaching results of different types of gold ores including oxide

More

A Review on Alternative Gold Recovery Reagents to Cyanide

After gold content is increased by physical and mechanical methods the concentrate is used as feeding ma terial for next steps. Gold concentrates are processed by chemical methods in order torecover up to 99 gold, depending on type and efficiency of the processes . The widely used chemical treatment process is the leaching with cyanide.

More

GOLD LECHING FROM A SAUDI ORE BY THE NONPOLLUTING

thiosulfate leaching of gold Chen, 2008. This shows how much a mineralogical investigation is important to be performed before leaching study of any gold ore by the thiosulfate process. Several gold localities are scattered in the Arabian Shield of the kingdom of Saudi Arabia which has about 20 million tons of recoverable gold ores.

More

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