ammonium thiosulfate mining gold leaching

Ammoniacal thiosulphate leaching of gold ore

2016-6-2 · The ammoniacal thiosulphate leaching of gold is dependant on both ammonia and thiosulphate concentration. The leaching is improved significantly at a particular ratio of ammonia to thiosulphate concentration and that ratio varies from ore to ore. Copper ions act as an oxidant and the gold dissolution

Read More

(PDF) Ammoniacal thiosulphate leaching of gold ore

Abstract. Ammoniacal thiosulphate leaching of gold finds a better substitute as it is non-toxic and environmentally safe as compared to the toxic cyanide system for

Read More

The treatment of copper–gold ores by ammonium

2002-10-1 · In conclusion, ammonium thiosulfate leaching for gold recovery preferably should be performed at: • low thiosulfate concentrations, ranging from 0.1 to 0.2 M; • an ammonia to thiosulfate ratio of 1–2; • copper concentrations ranging from 50 to 100 ppm; • an alkaline pH, preferably 9–10; • ambient temperature to 50 °C. 2.3.

Read More

Improvement of thiosulfate stability in gold leaching ...

2003-5-1 · Ammonium thiosulfate is a noncyanide lixiviant for gold leaching. However, the major problem with this leaching method has been the high consumption of reagents. To leach a mild-refractory copper-bearing gold ore, the authors used a reagent combination of 0.3M (NH4)2S2O3, 0.03M CuSO4 and 3M NH3 at pH 10.2 for 24 hours. In the testing, thiosulfate consumption

Read More

Thermodynamic analysis of gold leaching by ammoniacal ...

2001-11-1 · Thiosulfate offers a nontoxic alternative to cyanide for processing gold ores. The mechanism of leaching gold using ammoniacal thiosulfate solution is driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH 3 and S 2 O 3 2−.It is shown that an understanding of the copper speciation and sulfur speciation is required to optimize

Read More

Dissolution of Gold and Silver with Ammonium Thiosulfate ...

2017-4-20 · In the second stage, leaching of gold and silver values with ammonium thiosulfate was performed, and this yielded a removal of 97.06% silver and gold 86.66% with a liquid–solid ratio of 2:1. Thiosulfate consumption was 10.36 g/L, which is economically affordable for this head ore with gold and silver content of 0.3 g/ton and 310 g/ton ...

Read More

Thiosulfate leaching of gold—A 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 leaching of complex and carbonaceous-type ores. In addition, thiosulfate can be cheaper than cyanide.

Read More

Thiosulfate leaching of gold catalyzed by

2021-12-10 · Thiosulfate is a green gold lixiviant that has promise to replace cyanide at the gold mining industry. Hexaamminecobalt(III) (Co(NH 3) 6 3+) is effective in catalyzing the thiosulfate leaching of gold from ores, but the electrochemical behavior and catalytic leaching mechanisms remain unclear.This paper reports an in-depth investigation into the electrochemical behavior

Read More

Sodium Thiosulphate Gold Leaching

2016-6-2 · 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.

Read More

Improvement of thiosulfate stability in gold leaching ...

2003-5-1 · Ammonium thiosulfate is a noncyanide lixiviant for gold leaching. However, the major problem with this leaching method has been the high consumption of reagents. To leach a mild-refractory copper-bearing gold ore, the authors used a reagent combination of 0.3M (NH4)2S2O3, 0.03M CuSO4 and 3M NH3 at pH 10.2 for 24 hours. In the testing, thiosulfate consumption

Read More

Thiosulphate Stability In Gold Leaching Process

2016-6-2 · Ammonium thiosulphate is an alternative gold leaching Laaviant used to replace cyanide. The current problem of thiosulphate gold leaching is the high reagent consumption, To understand the decomposition chemistry of thiosulphate, solution stability tests were conducted in open and sealed vessek mder ambient temperature

Read More

Dissolution of Gold and Silver with Ammonium Thiosulfate ...

2017-4-20 · In the second stage, leaching of gold and silver values with ammonium thiosulfate was performed, and this yielded a removal of 97.06% silver and gold 86.66% with a liquid–solid ratio of 2:1. Thiosulfate consumption was 10.36 g/L, which is economically affordable for this head ore with gold and silver content of 0.3 g/ton and 310 g/ton ...

Read More

Thermodynamic analysis of gold leaching by ammoniacal ...

2001-11-1 · Thiosulfate offers a nontoxic alternative to cyanide for processing gold ores. The mechanism of leaching gold using ammoniacal thiosulfate solution is driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH 3 and S 2 O 3 2−.It is shown that an understanding of the copper speciation and sulfur speciation is required to optimize

Read More

Thiosulfate-copper-ammonia leaching of pure gold and ...

2017-5-10 · In thiosulfate gold leaching, Cu2+ ions are commonly used as oxidizing agents, while the thiosulfate ion acts as a ligand forming a soluble gold thiosulfate-ammonia complex (Aylmore and Muir, 2001). It was suggested that gold leaching in the absence of Cu2+ ions, with an external current acting as a oxidizer, is not possible

Read More

Thermodynamic evaluation of gold oxidation and

2003-5-1 · The copper-catalyzed gold oxidation and reduction mechanisms in ammonium thiosulfate solution were investigated by Eh-pH diagram based on the optimum reagent combination for a 60% (by weight) -75-μm silicate ore containing 16-g/t Au with the maximum gold extraction of 92% and the minimum ammonium thiosulfate consumption of 23 kg/t for 24-hours

Read More

Effect of pulp density on leaching of gold with time ...

2022-1-21 · Download scientific diagram | Effect of pulp density on leaching of gold with time [ammonium thiosulfate: 0.1M, copper sulfate: 40mM, pH: 10-10.5, stirring speed: 250 rpm, Temp: 25℃] from ...

Read More

COMPARISON OF CYANIDE AND THIOSULPHATE

2016-6-2 · currently the main gold leaching process in the world. However, gold cyanidation process has serious environmental risks if an accident occurs in the process because of the toxicity of cyanide. After some serious cyanide accidents some countries have campaigned to ban cyanide in gold mining industry.

Read More

Mining Thiosulphate Leaching - SGS South Africa

Thiosulfate leaching is a process that recovers gold from ore without the use of cyanide. SGS developed the thiosulfate leaching process because in some jurisdictions, increased regulation pressure means that cyanide cannot be used or transported. We are a global technical leader in the field of thiosulfate leaching.

Read More

The treatment of copper-gold ores by ammonium

The application of ammonium thiosulfate for the treatment of copper-gold ores has been investigated. Leaching studies were conducted with copper minerals, copper minerals with gold addition to solution and copper-gold samples of different copper and gold grades. The behaviour of thiosulfate, tetrathionate and sulfate in solution was studied using ion chromatography. The

Read More

Gold Leaching by Thiosulfate Solution and Recovery -

2003-1-1 · "In this investigation, a sponge gold sample (99.92% pure) has been leached with ammonium thiosulfate solution. The effects of CuSO4, (NH4)2S2O3, (NH4)2SO4, NH4OH and retention time on the gold leaching % (extraction %) and thiosulfate oxidation % (consumption %) have been studied. The copper ion acts as a catalyst in gold dissolution.

Read More

Dissolution of Gold and Silver with Ammonium Thiosulfate ...

2017-4-20 · In the second stage, leaching of gold and silver values with ammonium thiosulfate was performed, and this yielded a removal of 97.06% silver and gold 86.66% with a liquid–solid ratio of 2:1. Thiosulfate consumption was 10.36 g/L, which is economically affordable for this head ore with gold and silver content of 0.3 g/ton and 310 g/ton ...

Read More

Thiosulphate Stability In Gold Leaching Process

2016-6-2 · Ammonium thiosulphate is an alternative gold leaching Laaviant used to replace cyanide. The current problem of thiosulphate gold leaching is the high reagent consumption, To understand the decomposition chemistry of thiosulphate, solution stability tests were conducted in open and sealed vessek mder ambient temperature

Read More

Thermodynamic analysis of gold leaching by ammoniacal ...

2001-11-1 · Thiosulfate offers a nontoxic alternative to cyanide for processing gold ores. The mechanism of leaching gold using ammoniacal thiosulfate solution is driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH 3 and S 2 O 3 2−.It is shown that an understanding of the copper speciation and sulfur speciation is required to optimize

Read More

1-Ammonium Thiosulfate Ecological Viable Alternative to ...

2016-6-29 · Key words: Leaching, cyanide, ammonium thiosulfate. 1. Introduction The mining industry in the extraction of gold and silver has been using sodium cyanide (NaCN) in production processes for centuries. The NaCN is essential in the modern world, but its effects on health and the environmen thave led to the recent publicreaction to the use of NaCN.

Read More

Thermodynamic evaluation of gold oxidation and

2003-5-1 · The copper-catalyzed gold oxidation and reduction mechanisms in ammonium thiosulfate solution were investigated by Eh-pH diagram based on the optimum reagent combination for a 60% (by weight) -75-μm silicate ore containing 16-g/t Au with the maximum gold extraction of 92% and the minimum ammonium thiosulfate consumption of 23 kg/t for 24-hours

Read More

Thiosulfate-copper-ammonia leaching of pure gold and ...

2017-5-10 · In thiosulfate gold leaching, Cu2+ ions are commonly used as oxidizing agents, while the thiosulfate ion acts as a ligand forming a soluble gold thiosulfate-ammonia complex (Aylmore and Muir, 2001). It was suggested that gold leaching in the absence of Cu2+ ions, with an external current acting as a oxidizer, is not possible

Read More

Method of gold extraction from sulphide gold-bearing ores

Method of gold extraction from sulphide gold-bearing ores. C22B3/04 - by leaching (C22B0003180000 takes precedence);; C22B11 - Obtaining noble metals. FIELD: metallurgy. SUBSTANCE: method includes leaching by solution of mixture of hydrosulphite and sodium thiosulfate and ammonium, sorption of complex thiosulfate-gold on heavy-basic anionite ...

Read More