sodium sulfite and gold leaching

Role of copper(II), carbonate and sulphite in gold leaching …

1.. IntroductionThiosulphate is an intermediate product of the oxidation of iron sulphides (Mishra and Osseo-Asare, 1988).Thus, mill tailings waters from sulfide leaching operations contain thiosalts (S 2 O 3 2-, S 4 O 6 2-, S 3 O 6 2-) produced by the degradation of sulphide minerals.When discharged, the mill waters cause environmental …

Silver leaching with the thiosulfate–nitrite–sulfite–copper …

Highlights. Thiosulfate–nitrite–copper is a promising silver leaching alternative system. Cupric–ammonia complexes are produced in-situ without the addition of ammonia in the system. Antlerite and copper hydroxide are produced on the silver particle. Sulfite decreases the oxidative ability of the system and the silver leaching …

A Review of Thiosulfate Leaching of Gold: Focus …

The reason is that it not only reduces thiosulfate consumption observably via decreasing the redox potential of leach solution significantly but also is beneficial to gold recovery mainly owing …

Recovery of tellurium from high tellurium-bearing

Sb and Te in Te-bearing alkaline skimming slag were extracted into a leach solution using a two-stage sodium sulfide leaching process. In this study, a possible method for selective recovery of Sb ...

Minerals | Free Full-Text | Effect of Stabilizer on Gold Leaching …

The thiourea gold leaching cyclic voltammetry curves are shown in Figure 2a,b for sodium sulfite and sodium silicate, respectively. As shown in Figure 2 a, with Na 2 SO 3 as a stabilizer and with positive scanning, the cyclic voltammetry curve of this system had its first oxidation peak at 0.16 V, which matched the reaction of thiourea ...

Gold Leaching Using Thiourea from Uranium Tailing …

Results led to the conclusion that the leaching rate of gold with acidic thiourea was diffusion controlled, which was supported by the reaction activation energy of 9.32 kJ mol −1 in the absence of sodium sulfite and 7.62 kJ mol −1 in the presence of sodium sulfite. The efficiency of gold dissolution, which reached maxima at pH 1.5 ...

Cyanide-free gold leaching in exceptionally mild chloride …

Cyanide-free mild chloride leaching was investigated. •. Gold could be recovered even at <520 mV vs. Ag/AgCl in carbon-in-chloride-leach mode. •. Copper was a stronger oxidant than iron in gold leaching. •. Gold was oxidized by in-situ dissolving impurities. •. Seawater contains enough chlorides to dissolve gold.

A Review of Thiosulfate Leaching of Gold: Focus …

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 …

Sulfidic gold ore leaching by cysteine in the presence of …

Sulfidic gold ore was leached by cysteine to determine its efficacy as a cyanide alternative. The results show that the best conditions for leaching, which …

Ion exchange adsorption and elution for recovering gold …

Fig. 2 shows the column elution profile for gold loaded resin at 5 BV h − 1 using 1 M ammonium nitrate in the presence and absence of sulfite. In the absence of sodium sulfite, the elution of gold with 1 M ammonium nitrate is still incomplete after 25 BV.Previous work (O'Malley, 2001) required concentrations of 2 M ammonium nitrate or …

Effect of sodium carbonate on alkaline self-leaching of gold …

The interference of sulfite and sulfide in the solution was eliminated by formaldehyde and zinc acetate added, and the concentration of thiosulfate was determined by iodimetry. ... In order to explore the effect of sodium carbonate in gold self- leaching system, the most appropriate sodium hydroxide concentration (0.4–0.7 M) was …

Sustainability | Free Full-Text | Biogenic Production …

Sodium sulfide in bacterial medium was determined to be the most effective method of producing Bio-TS for gold leaching. The system was determined to be effective when up to 70% seawater was …

Sulphide Gold Ore Treatment by Leaching and Flotation Process

A Flowsheet to recovery gold from sulfide ores. There are many arrangements and combinations using flotation in conjunction with treatment of gold ores. The two gold process flowsheets shown, with some variations, are probably the most commonly used. In Gold Flowsheet No. 1 the ore is ground in water to such a size as to …

Gold leaching by organic base polythionates: new non-toxic …

Then the highly basic anion exchanger is regenerated with a solution of a mixture of sodium and ammonium sulfite and sulfate. After the highly basic anion exchanger regeneration, it is transferred to the process of the thiosulfate-gold complex sorption. ... Gold leaching by polythionates (new non-toxic technology) (in Russian), …

A systematic review of gold extraction: Fundamentals, …

Malononitrile was comparable to equal molar quantities of sodium cyanide in leaching gold from oxide ore and yielded 10–20 % higher recovery in leaching a refractory carbonaceous ore, although dissolution was slower with malononitrile than with cyanide (Heinen et al., 1970). Nitriles are also toxic, but they are far less harmful than cyanide.

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 …

Recovery of gold from refractory gold ores: Effect of pyrite …

Y.H. Hu, G.F. Guo, and G.Z. Qiu, Study on mechanism of gold leaching by thiourea in the presence of sodium sulphite, J. Cent. South Univ. Technol., 7(2000), No. 3, p. 113. Article CAS Google Scholar S. Ardiwilaga, Effects of cysteine and oxygen on recovery of cemented gold from leach liquors in a thiourea system, Miner.

Recovery of tellurium from high tellurium-bearing materials …

Tellurium could be pre-leached from the telluride-type gold flotation concentrate through the Na2S + NaOH alkaline leaching process to achieve the effective separation of tellurium from noble metals, which, when eliminating the adverse effects ofTelluride on the leaching of gold and silver, provides new ideas for the extraction of …

Thiourea Leaching: An Update on a Sustainable Approach for …

Rizki et al. reported that although the addition of sodium sulfite to the leaching system did not improve the gold recovery, the remaining thiourea in solution …

A clean and efficient innovative technology for refractory sulfide gold

1. Introduction. Gold is a precious strategic metal that is driving everyday life, the electronics industry, and the global economy (Zhan et al., 2021; Zhang et al., 2022a, Zhang et al., 2022b, Zhang et al., 2022c, Zhang et al., 2022).However, with the depletion of high-quality gold ore, refractory gold resources (gold recovery efficiency …

Recovery of gold from sulfide refractory gold ore: Oxidation …

The gold leaching rate evidently increased with the reagent content and slurry temperature of the pretreatment, reaching a maximum of 86.55% at 60 °C and CaO and Na 2 CO 3 concentrations of 16 and 32 g/L, respectively. ... The effects of sodium sulfide and sodium hydroxide concentration, temperature, leaching time and …

Study on mechanism of gold leaching by thiourea in the …

The activation energy required for gold dissolution in thiourea solution with sodium sulphite is 20.9 kJmol−1 in the absence of sodium sulphite. It is evident that sodium sulphite has a ...

Thiourea Leaching: An Update on a Sustainable Approach for Gold …

Thiourea has received attention as an alternative lixiviant for gold leaching due to its fast reaction kinetics and less harmful nature. This review aims to provide an up-to-date evaluation of ...

Enhancement of gold extraction from biooxidation residues using …

Figure 1 demonstrates that lixiviant containing sodium sulphite can significantly accelerate the gold leaching process. To reach a 93% gold extraction, the leaching time was shortened by almost 5 hours when sodium sulphite was present. Furthermore, the presence of sodium sulphite could also greatly reduce the …

Recovery of gold from sulfide refractory gold ore: Oxidation …

Most of the gold in the roasting slag is recovered by thiourea/cyanide leaching process, however, the leaching residues (gold tailings) obtained from thiourea leaching process or the sodium cyanide leaching still contain 9–16 g/t gold, which is difficult to recover and is usually discarded with the leaching residues; This …

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 was suppressed because of the unwanted decomposition of thiosulfate on the surface of sulfide minerals. ... at the same time decomposing thiosulfate to form (S 2 O 3) 3 5−, …

Study on mechanism of gold leaching by thiourea in the

In the presence of sodium sulphite, the effective concentration of thiourea is increased and the dissolution rate of gold in thiourea solution is greatly increased. The activation energy required for gold dissolution in thiourea solution with sodium sulphite is 20.9 kJ·mol −1 in the absence of sodium sulphite. It is evident that sodium ...

Extraction of gold and silver from Turkish gold ore by …

Sodium sulfite concentration varied between 0 and 0.2 M and ... An acceptable gold leaching rate of 0.18 to 0.27 μmol·m⁻²·s⁻¹ could be obtained under the conditions of above 0.1 mol/L ...

A review of environmentally friendly gold lixiviants: …

Gold leaching by polysulfides was proposed in 1962; the most used polysulfide leaching reagents are ammonium sulfide or sodium sulfide. The …

Thiosulfate leaching of gold—A review

Abstract. 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. The application to different ore types and process options have also been discussed. The thiosulfate leaching process it catalysed by …

Study on mechanism of gold leaching by thiourea in the

The results show that in the absence of sodium sulfite the dissolution rate of gold in thiourea solution is relatively slow and it increases with the increase of the concentration …

precipitating with sodium sulfite

Either SMB or Sodium Sulfite, or even sulfur dioxide gas will work fine for reducing gold in HCl-Cl solutions. When highly concentrated the solution will lean towards deep orange to deep red when highly concentrated. I use dry SMB exclusively now days and never have had to heat the solution to get the gold to drop.

Recovery of tellurium from high tellurium-bearing

A possible process for the recovery of tellurium from antimony and tellurium materials by alkaline sulfide leaching followed sodium sulfite precipitation was proposed. The tellurium and antimony materials were leached in 100 g/L Na 2 S solution at 80 °C for 60 min with L/S ratio of 10:1, in which 91.24% Te and 92.51% Sb were …

Recovery of tellurium from high tellurium-bearing

In this work, a flow sheet (Fig. 1) for the recovery of tellurium from the high tellurium-bearing materials by alkaline sulfide leaching and sodium sulfite precipitation combined with downstream treatments was proposed.The effects of various parameters on tellurium dissolution and recovery of dissolved tellurium by sodium sulfite precipitation …

Gold leaching from ores using biogenic lixiviants – A review

Gold leaching recovery from carbonaceous-argillaceous slate ... In a commercial-scale gold tank cyanidation, a sodium or potassium cyanide solution usually is used with a concentration of 0.01–0.05% (100–500 mg/L) ... and sulfite ions to solubilize gold and silver. About 79% of the gold and 59% of the silver were leached within 30 days.

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