A novel method for the recovery of silver from thiosulphate leach
Thiosulphate leaching offers several advantages in the treatment of copper-rich and preg-robbing refractory gold ores of which traditional cyanide leaching fails to economic and technically viable extraction of gold (Aylmore and Muir, 2001, Marsden and House, 2006, Wang et al., 2020, Yazici et al., 2015, Zhang and Senanayake, 2016).Web
A study of the factors affecting copper cementation of gold from
Thiosulphate is a metastable sulphur species and will eventually decompose in aqueous solutions. Its stability, however, is reported to be enhanced by the presence of sulphite ions 3, 4, 5. Since thiosulphate leaching of gold is, as yet, commercially underdeveloped, there is no accepted method for recovery of gold from thiosulphate …Web
Thiosulfate leaching kinetics of gold in the presence of copper and
This leads to the decrease in the leach rate as the copper (II)-thiosulfate reaction occurs. Thiosulfate leaching kinetics of gold in presence of copper and ammonia 1075 x 6. 4. 2. IBm ii& I& lOmM 5mM 0 o 1'o .b do do loo % Cu (ll) Fig.3 Effect of total copper concentration on gold leaching.Web
Review of gold leaching in thiosulfate-based solutions
In this review, the basic theory and process development of some main gold leaching systems based on thiosulfate solutions are summarized to illustrate the research status on thiosulfate leaching Feng XIE, et al/Trans. Nonferrous Met. Soc. China 31 (2021) 3506âˆ'3529 3508 process.Web
Kinetic studies of gold leaching from a gold
The optimal pH value for gold leaching is 10.0, and gold can be effectively extracted at ambient temperature. The apparent activation energy is determined to be 5.68 kJ/mol, and this indicates that the gold leaching in the Co-NH 3-S 2 O 3 2− system is likely to be controlled by the diffusion of reactants and products through a solid layer ...Web
A Review of Thiosulfate Leaching of Gold: Focus on …
The cupric-ethanediamine catalyzed thiosulfate leaching using a synergistic additive of cetyltrimethyl ammonium bromide was …Web
Metals | Free Full-Text | Leaching Behavior of Gold and Silver …
Ammonium thiosulfate is an alternative lixiviant for the hydrometallurgical treatment of sulfide gold ores. The present study is primarily focused on ammonium thiosulfate leaching of gold (Au) and silver (Ag) from the sulfide ore (Sunshin mine in Korea). The main chemical composition of the concentrate was Au (84 ppm), Ag (852 …Web
Thiosulphate Leaching | SGS Canada
We are a global technical leader in the field of thiosulfate leaching. Our laboratory and industry experts have spent years designing and developing the technique into a viable alternative to cyanide for some gold-bearing ores. Thiosulfate leaching offers a number of benefits related to gold recovery yields and environmental concerns:Web
The Effects of Common Associated Sulfide Minerals on Thiosulfate
D. Feng and J.S.J. van Deventer, "Thiosulphate leaching of gold in the presence of carboxymethyl cellulose," Mineral Engineering, 24 (2011), 115–121. CrossRef Google Scholar . G. Senanayake, "Analysis of reaction kinetics, speciation and mechanism of gold leaching and thiosulfate oxidation by ammoniacal copper (II) solutions," …Web
SN values for extraction of gold (t=12 h) at three
The extraction of gold/silver from a copper-bearing pyritic gold concentrate (62 g/t Au, 110 g/t Ag and 0.3% Cu) in thiosulphate solutions was investigated in this study. The concentrate is ...Web
Leaching of Gold and Silver from a Complex Sulfide …
Application of pretreatment in gold thiosulfate leaching systems. Materials (Gold Content) Pretreatment Optimal Conditions Gold Extraction Sulfide gold concentrate with high Fe, As and Sb (12.6 g/t) Oxygen pressure leaching 0.03 mol/L NiSO 4, 1.0 mol/L NH 3H 2O, 0.3 mol/L Na 2S 2O 3, 6 h 94.7% [40] Sulfide gold concentrate with high C, …Web
Metals | Free Full-Text | Leaching of Gold and Silver from a …
The leaching behaviors of gold and silver from a complex sulfide concentrate in copper-tartrate-thiosulfate solutions were investigated in this paper. Experimental parameters, including temperature, initial pulp pH, and concentration of copper, tartrate, and thiosulfate, were systematically studied. The copper-tartrate-thiosulfate leaching system …Web
Minerals | Free Full-Text | Extraction of Gold and Copper from
This study presents the novel idea of a cyanide-free leaching method, i.e., glycine-ammonia leaching in the presence of permanganate, to treat a low-grade and copper-bearing gold tailing. Ammonia played a key role as a pH modifier, lixiviant and potential catalyst (as cupric ammine) in this study. Replacing ammonia with other pH …Web
Thiosulphate leaching for gold hydrometallurgy
Abstract. Thiosulphate leaching of precious metals has been developed as an alternative and non-toxic technique to the conventional cyanidation. This process has advantages over cyanide in a decreased interference from foreign cations and a lower environmental impact. Ammoniacal thiosulphate solution allows the solubilization of …Web
Recovery of Gold and Silver from Oxidation Leach Residues …
An atmospheric ammoniacal thiosulphate leach system was developed to recover gold and silver from residues of the amoniacal oxidation leaching of sulphidic copper concentrates. Extractions of 88 - 95% Au and 83 - 98% Ag were attained within 2 to 4 hours at 40 - 60°C in thiosulphate leaching of the oxidation leachWeb
(PDF) Conference Proceeding: Extraction of Silver from Waste X …
Cyanide leaching of the ore resulted in a gold extraction of only 22% while gold extractions as high as ~62% were achieved by ammoniacal thiosulphate leaching. The concentrations of thiosulphate (S 2 O 3 2-) and ammonia (NH 3) were identified to be statistically significant factors affecting the extraction of gold, while the effect of addition ...Web
A systematic review of sustainable gold extraction from raw ores …
Thermodynamic analysis of ammoniacal thiosulphate leaching of gold catalysed by Co(III)/Co(II) using Eh-pH and speciation diagrams. Hydrometallurgy (2018) ... are desired to extract gold for the sustainable hydrometallurgy of gold. Leaching characteristics of gold were examined using thiourea (TU) and ethylene thiourea (ETU) …Web
Thiosulfate leaching of gold—A review
The ammoniacal thiosulfate leaching process for gold and silver extraction has been reviewed in terms of leaching mechanism, thermodynamics, thiosulfate …Web
Leaching of Gold from an Oxide Gold Ore with Copper–Tartrate
Until recently, cyanidation was the primary method of choice for gold leaching, having been used in the gold mining industry since the first patent was issued in 1887. 1 However, with the newly enacted laws and regulations on environmental protection and public security, cyanidation has been banned in certain jurisdictions due to the …Web
A Review of Ammoniacal Thiosulfate Leaching of Gold: An …
ABSTRACT This literature review provides an update of ammoniacal thiosulfate as a potential lixiviant of gold, the history of thiosulfate leaching and recent …Web
Thiosulfate leaching of gold—A review | Semantic Scholar
A Review of Thiosulfate Leaching of Gold: Focus on Thiosulfate Consumption and Gold Recovery from Pregnant Solution. Thiosulfate leaching is a promising alternative to cyanidation, and the main hindrances for its wide commercial application are the high thiosulfate consumption and the difficult recovery of….Web
(12) United States Patent (45) Date of Patent: Oct. 14, 2003
patent is extended or adjusted under 35 WO WO 94/06944 3/1994 U.S.C. 154(b) by 0 days. WO WO OO/65112 11/2000 (21) Appl. No.: 09/837,756 OTHER PUBLICATIONS (22) Filed: Apr. 17, 2001 Hemmati, et al., Study of the Thiosulphate Leaching of Gold 9 O O from Carbonaceous Ore and the Ounatitative DeterminationWeb
Improvement of thiosulfate stability in gold leaching | Mining
To leach a mild-refractory copper-bearing gold ore, the authors used a reagent combination of 0.3M (NH 4) 2 S 2 O 3, 0.03M CuSO 4 and 3M NH 3 at pH 10.2 for 24 hours. In the testing, thiosulfate consumption was 30 kg/t of ore. Dissolved oxygen and copper species were found to be responsible for the rapid decomposition of thiosulfate.Web
A review of gold extraction using noncyanide lixiviants
Alkaline sulfur-containing lixiviants, including thiosulfate, polysulfides, and alkaline sulfide solutions, stand out as a promising class of alternatives to cyanide because of their low toxicity, high efficiency, and strong adaptability. In this paper, we summarized the research progress and remaining challenges in gold extraction using these noncyanide …Web
Ammoniacal thiosulphate leaching of gold in the presence of pyrite
The addition of sulphate enhanced gold leaching by retarding the dissolution of pyrite in ammoniacal thiosulphate solutions. XPS analysis indicated the presence of …Web
The ammoniacal thiosulfate system for precious metal recovery
The hydrometallurgical treatment of gold and silver ores by ammoniacal thiosulfate solutions in the presence of a copper catalyst has been actively studied in recent years. Such a process strategy is very attractive due to the low toxicity of the lixiviant and the efficient recovery of the precious metals from difficult-to-treat ores. Important features …Web
A review of gold extraction using noncyanide lixiviants: Fundamentals
Alkaline sulfur-containing lixiviants, including thiosulfate, polysulfides, and alkaline sulfide solutions, stand out as a promising class of alternatives to cyanide because of their low toxicity, high efficiency, and strong adaptability. In this paper, we summarized the research progress and remaining challenges in gold extraction using these noncyanide …Web
Leaching and Recovery of an Oxide Gold Concentrate Using Ammoniacal
Thiosulfate leaching-resin adsorption recovery, an environmentally friendly process, has been developed to efficiently extract gold from an oxide gold concentrate. 80.5% of gold extraction could be achieved by thiosulfate leaching under the conditions of (NH 4) 2 S 2 O 3 0.2 mol/L, CuSO 4 0.025 mol/L, NH 3 1.5 mol/L and leaching time 8 h, …Web
A Review of Ammoniacal Thiosulfate Leaching of …
A Review of Ammoniacal Thiosulfate Leaching of Gold: An Update Useful for Further Research in Non-cyanide Gold Lixiviants. ... and refractory ores/concentrates and the fundamentals relevant to the …Web
The treatment of copper–gold ores by ammonium thiosulfate leaching
Cyanidation was compared as a baseline for gold extraction; ammoniacal thiosulfate ((NH 4) 2 S 2 O 3) and non-ammoniacal thiosulfate (Na 2 S 2 O 3) were investigated as alternative leaching conditions. In this work, POX achieved a high copper removal percentage and left 0.66% copper in the residue.Web
