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 …
CYANIDE DETOXIFICATION OF CYANIDATION TAILS …
been adopted by the gold industry to meet the International Cyanide Management Institute (ICMI) ... The sulfite ion is the reactant in the process and thus sodium sulfite (Na 2SO 3) or sodium metabisulfite (Na 2S 2O 5 ... As the copper concentration for the Sample A leach tails was less than 50 mg L-1 (Table 1), ...
Increased Recovery of Gold Thiosulfate Alkaline Solutions by …
Thiosulfate leaching combined with ion-exchange resins is an innovative alternative for gold recovery. According to the properties of activated carbon, it could replace resins in the gold recovery process, improve efficiency, and reduce operating cost. ...
Selective Electrochemical Gold Recovery from Leaching …
This work presents a study of the selective electrowinning of gold from thiosulfate electrolyte, taking into account difficulties related with low gold concentration …
Gold Leaching Using Thiourea from Uranium Tailing …
Compared with leaching without sodium sulfite, the addition of sodium sulfite significantly increases gold dissolution. This effect becomes more pronounced as the sodium sulfite concentration is increased. Without using any stabilizing additives, only 45% of the gold is recovered from the leach solution.
Review A systematic review of gold extraction: Fundamentals
This paper aims to summarize these studies and present a systematic review of the mineral processing of gold ores, with a particular focus on alternative leaching …
A systematic review of sustainable gold extraction from …
Drawing on recent experimental and commercial developments, this review reappraises potential substitute leach reagents for cyanide in the gold mining…
Metals | Free Full-Text | Optimization of Gold Dissolution …
The nature of gold (Au) ore deposits plays an essential role in determining the best gold recovery method as an alternative to cyanidation, considering environmental concerns. Thiourea (Tu) leaching of gold is an alternative lixiviant for treating sulfide gold ores and concentrates. The present study investigated the leaching behavior of Au from …
Recovery of gold from sulfide refractory gold ore: Oxidation …
The sulfides or oxides, which seriously affect the gold leaching process or encapsulate gold, are destroyed by alkali compounds (e.g. sodium hydroxide, sodium sulfide). It has advantages of high efficiency, not releasing harmful gases, flexible product solutions and low energy cost; Poor adaptability to oxide ores.
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 stability, and gold recovery options.
Leaching Kinetics of Antimony from Refractory Gold Ore …
The leaching kinetics of antimony from refractory gold ore in alkaline sodium sulfide was investigated under ultrasound. The influence of factors such as stirring speed, temperature, the concentration of sodium hydroxide and sodium sulfide and particle size, was studied.
Selective Pre-leaching of Tellurium From Telluride-Type Gold
The direct leaching gold leaching rate of telluride-type gold concentrate in this experiment was only 32.00%, which is refractory gold ore. ... Recovery of tellurium from high tellurium-bearing materials by alkaline sulfide leaching followed by …
Gold leaching from oxide ores in alkaline glycine solutions in the
Copper sulfide was then recovered from the leach solution via precipitation by sodium hydrosulfide. Gold leaching in the glycine + permanganate system was thoroughly studied with an emphasis on the process's kinetics mechanisms.
A review of gold extraction using noncyanide lixiviants
In this paper, we summarized the research progress and remaining challenges in gold extraction using these noncyanide reagents. After a brief introduction …
precipitating with sodium sulfite
If there is no free nitric left in the solution, it will take about the same weight of sodium sulfite as you have gold, or a little more. I would dissolve about that much in a minimum amount of hot water, add some of it, stir well, and test with stannous chloride. ... Lye doesn't leach gold, so where is it! Latest: Juan-2-many; Yesterday at ...
Review of gold leaching in thiosulfate-based solutions
Numerous non-cyanide leaching lixiviants have been developed, among which thiosulfate is considered the most promising alternative to cyanide due to its non …
Gold Leaching in an Alkaline Thiourea Solution
Gold leaching by thiourea has been investigated in an alkaline solution. In the presence of both Na 2 SO 3 and Na 2 S 2 O 8, the chemical dissolution of gold can be accomplished in the alkaline thiourea solution. It was found that used as a buffer, SO 2- 3 can prevent thiourea from further decomposing into some insoluble species in contact …
Effect of Pyrite and Quartz on Silver Leaching During Gold …
The addition of sodium sulfite can reduce the formation of iron silicate and increase the leaching rate of silver by promoting the conversion pyrite to iron oxides directly. This research provides a theoretical basis for improving and further improving the roasting leaching effect of silver.
Selective Electrochemical Gold Recovery from Leaching …
This work presents a study of the selective electrowinning of gold from thiosulfate electrolyte, taking into account difficulties related with low gold concentration and metal impurities that usually limit gold recovery.
SERS and electrochemical studies of the gold
The peaks observed could possibly be associated to the presence of sulfate or sulfite at the gold–solution interface ... responsible for hindering gold leaching in the thiosulfate solution, ... The leaching current for the sodium thiosulfate solution is higher than in the preceding section because it was determined for a freshly renewed gold ...
Effects of pyrite, quartz and sodium sulfite on roasting of a
Semantic Scholar extracted view of "Effects of pyrite, quartz and sodium sulfite on roasting of a refractory sulfide concentrate and gold, silver, copper leaching during cyanidation" by Wei Yang et al.
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 …
Thiosulphate leaching for gold hydrometallurgy
Loaded gold on CMA was easily eluted using a sodium sulfite solution, achieving a gold recovery of 62.2 %, even after four adsorption–desorption cycles. Finally, in the actual gold ore leachate adsorption and slurry adsorption method, the adsorption of gold and copper by CMA is approximately 98 % and 7 %, respectively.
Metals | Free Full-Text | A Pretreatment of Refractory Gold …
The effects of HAsBS ore on gold leaching in ammonium thiosulfate solutions were investigated, and it was found that gold extraction in the presence of HAsBS ore …
Effect of Stabilizer on Gold Leaching with Thiourea in …
The effects of these stabilizers on the activation energy of alkaline thiourea gold leaching was also studied. The results showed that sodium silicate was more suitable as a stabilizer in this system than sodium sulfite because the peak current of gold dissolution with sodium sulfite was higher than that with sodium silicate, but the …
Electrochemical Behavior of Sodium Sulfite in Alkaline …
The polarization curves and AC impedance spectroscopy of gold and platinum electrodes were measured by an electrochemical workstation to study the effect of sodium sulfite on the dissolution of gold in alkaline thiourea solution. The results showed that the corrosion potential (Ecorr) of gold with sodium sulfite was -0.776 V, which is far below that of …
(PDF) A systematic review of gold extraction: …
Over the past three decades, a significant amount of literature has examined alternative lixiviants to cyanide for recovering gold, while few industrial applications have been reported due to...
Review Recovery of gold from secondary sources—A review
Ferrous sulfate, sodium sulfite, potassium sulfite, sulfur dioxide and hydrogen peroxide, formic acid and formaldehyde: Oliver and Richard, 1974: Adsorption: ... Chloride gold leaching is more difficult to apply than cyanide leaching for two main reasons: (1) special stainless steel and rubber-lined equipment are required to resist the …
Effect of Na2SO3 on electrochemical aspects of gold …
The regularities of electrochemical deposition and dissolution of gold in the mixed sulfite-thiocarbamide electrolytes in the absence and in the presence of sodium sulfide additive are studied by…
Sulfidic gold ore leaching by cysteine in the presence of …
Thereafter, an attempt was made to improve the efficacy of the leaching by adding sodium sulfite (Na 2 SO 3), which has been shown to improve the leaching efficiency of relatively unstable reagents like thiosulfate and thiourea by mitigating their oxidation as described in the following section (Marsden and House, 2006). 3.2.5.