Oxidative pretreatment of refractory gold ore using …
— A novel pretreatment method for refractory gold ore using ultrasound-activated persulfate was developed to overcome the low extraction efficiency of gold in …
Treatment of copper-rich gold ore by cyanide leaching, …
— Copper cyanide complexes in cyanide leach solutions deteriorate the recoveries of gold. Herein, five phosphonate-based [P204] − ionic liquids were synthesized, which were pioneered to apply to extraction of copper cyanide complex ions in cyanide leach solutions. In the extraction process, macroscopic layered solids rich in copper …
Refractory Gold Ore Treatment Methods
— Cyanidation and concentration of gold and silver ores. List Gold Refractory Process Methods. The use of roasting for the oxidation of sulfides has declined over the years. However. Resolute Mining resurrected the Syama project in Mali by converting the process from a whole-ore roast to flotation followed by concentrate roasting.
Process mineralogy characteristics of acid leaching …
Keywords: acid leaching residue; roasting; process mi neralogy; precious metals; occurrence states 1. Introduction Gold ore accounts for over two-third of the world's gold reserves, and a third of produced gold comes from refractory gold ores [1–3]. Refractory gold ores with low grades, fine dissemination, and high impurity content have ...
Optimization Process of the Refractory Gold Ore Extraction …
— Hypochlorite leaching system is a strong oxidizing solution for metal sulfides, which are naturally associated with gold extraction. This study evaluated the hypochlorite leaching of refractory gold ore by using the response surface method–central composite design (RSM-CCD) as a statistical approach in determining the optimum condition of …
Study on Technological Mineralogy Analysis and Pretreatment …
— Under the conventional cyanide leaching system, the gold leaching rate is low, only about 75%. In order to search for a better recovery of gold from refractory gold concentrate containing arsenic after pretreatment and to improve the gold leaching effect, the process mineralogy and pretreatment of gold concentrate containing arsenic were …
Nitric Acid Pretreatment Applied to a Refractory Gold-Tellurides Ore
— This paper presents the results obtained by processing a gold and silver telluride mineral concentrate from a mine in Colombia. An acid wash, also known as acidification, was carried out, followed by oxidation with nitric acid as a pretreatment. Cyanidations of the pretreatment residues were carried out and the results were …
Potential pre-treatment and processing routes for …
2.1 Microwave pre- treatment of refractory gold ores . Most of refractory gold occurs within sulphide minerals such as FeS ... that reduces leaching rate of gold in the roasting process, and also releases gases such as SO 2 and As 2O 3 that are serious environmental pollutants. Also, roasting treatment involves the production of sulphuric acid ...
Evaluation of pre-treatment methods for gold recovery …
Pre-treatment methods for ores, or concentrates. Pre-treatment method Phases in gold-bearing ore or concentrate Reference. Flotation Sulphides, silicates, carbonate Allan and Woodcock (2001), Yalcin and Kelebek (2011) Biological oxidation Silicates, sulphates, sulphides, oxides Asamoah, Skinner, and Addai-Mensah(2018) Gravity separation and ...
Selective alkaline leaching of antimony from Low-grade refractory gold …
— Wu (Wu et al., 2019) and Rusalev (Rusalev et al., 2020) studied the effect of different factors on antimony in the sodium sulfide leaching process for treating high-grade antimony gold ore by electrochemical method. And it is found that the reduced iron powder could effectively decrease gold leaching in Na 2 S leaching solution.
Complete process and equipment solutions for …
— The current high gold price is increasing the focus on the development of refractory gold ores and concentrates. Outotec can deliver the three main oxidative processes for the treatment of refractory …
Recovery of gold from refractory gold ores: Effect of …
the effect of impurities in the gold ore or thiourea leaching system on thiourea. The gold in RGOs is usually locked by metal sulfides, such as pyrite, and preg-robbed by carbon …
A Preliminary Study on Nitric Acid Pre-treatment of Refractory Gold
— Effect of nitric acid pre-treatment on the extraction of silver from the ground ore (d 80 : 50 µm) in cyanide leaching (Cyanidation conditions: 1.5 g/L NaCN, pH 10.5, 25 3 C, flow rate of air: 1. ...
Pretreatment of refractory gold ore by curing with …
The experimental results showed that under the conditions of liquid solid ratio 3:1, curing temperature 240 °C and the reaction time 1.5 h, the weight loss rate and iron removal …
Optimizing the alkaline oxidation pretreatment of a refractory gold ore …
— Optimization of the pretreatment process of gold refractory ore from Zarshuran gold mine was carried out using Taguchi method-orthogonal array optimization technique (OAOT). ... [21] Aazami M, Lapidus G and Azadeh A 2014 The effect of solution parameters on the thiosulfate leaching of Zarshouran refractory gold ore Int. J. Miner. …
Improvements in gold ore cyanidation by pre-oxidation with …
— Section snippets Survey of process parameters before the H 2 O 2 pre-oxidation trial. For a period of 5 days the ore that feeds the leaching circuit was sampled and characterized for mineralogical composition and tested for the determination of the oxygen uptake rate.In addition, measurements of dissolved oxygen (DO) and free …
Pretreatment of refractory gold minerals by ozonation …
— The pretreatment of gold ores before cyanidation is a challenging problem due to the world's annual huge waste of refractory gold minerals. Generally, the leaching of gold by cyanidation without any pre-oxidation causes an extraction lower than 90%. In recent decades, a variety of treatment and pretreatment methods have been used to …
Gold recovery from refractory gold concentrates by …
be exposed. Mohammadi et al. investigated ammoniacal thiosulfate leaching of refractory oxide gold ore, and they obtained maximum gold extraction of 55% (Mohammadi et al., 2017). Shen et al. had researched the direct thiosulfate leaching of gold from refractory ore, and they achieved gold recovery of only 70% (Shen et al., 2013).
Processing technologies for gold-telluride ores
— Gold telluride ores are important gold refractory ores due to the presence of sulfides and other gangue materials. The classification and main physical properties of gold telluride ores were described, and possible treatment methods including flotation, leaching, and oxidation were reviewed. The results show that flotation procedures are much …
Mineral Phase Evolution during Oxidation Roasting Pretreatment …
— Arsenious and sulphur-bearing micro-disseminated gold ore is a kind of typical refractory Carlin-Type. The gold in Carlin-Type gold ore grains is distributed finely, existing as invisible or submicroscopic gold, encapsulated in arsenopyrite and pyrite. The technical difficulty of treatment Carlin-Type gold ore lies in how to release the fine gold …
Gold recovery from refractory gold concentrates by pressure oxidation
— In this work, a method for the extraction of gold from the cyanide tailings (CT) was investigated. Sulfuric acid was used as a pretreatment leaching solution and calcium hypochlorite was used as a ...
Getting a Handle on Refractory Ore May Determine Gold…
— According to a recent article by global consulting firm McKinsey, approximately one-quarter of the gold in geological reserves and resources can be considered refractory, with gold production from refractory ores expected to grow 1.4 % in the next four years, versus 0.3 % for non-refractory ores.
MODELING OF HIGH PRESSURE PRETREATMENT …
preparation techniques for the refractory ores. The major developments in the pressure hydrometallurgy of gold ores and concentrates began from the 1980s. The oxidative …
Optimization process of refractory gold ore extraction by …
Refractory gold ore contains sulfide minerals like pyrite, chalcopyrite and sphalerite that are difficult to be directly leached by cyanidation or by lixiviants such as thiourea and halides. In such cases, it is necessary to perform oxidative pretreatment of the ore to oxidize the sulfide matrix, and gold particles can be exposed to the solution during the leaching process [1]. …
Pretreatment Process on Refractory Gold Ores with As
— As a refractory gold ore, a large proportion of finely disseminated gold is encapsulated in the sulfide matrix of arsenopyrite, resulting in inefficient gold recovery via the conventional leaching ...
Effect of Oxidative Pretreatment and Lead Nitrate Addition …
— Cyanidation is the main process in gold leaching. There are several parameters that affect gold recovery and cyanide consumption. In this paper, the effect of the oxidative pretreatment and lead nitrate addition on the cyanidation of Zarshuran refractory gold ore containing 3.32 ppm Au, 1.09% As, and 0.5% sulfur were …
Review Pretreatment Process on Refractory Gold Ores …
The process of crushing or decomposition before gold leaching is called pretreatment of refractory gold. Statistics show that, in the world, about 2/3 gold resource belongs to the …
Extraction and Recovery of Gold from both Primary and …
iii and the type of organic solvent. More than 94% of gold could be selectively extracted and recovered after 9 hours which was significantly faster than the current cyanidation process with 35
Pretreatment of refractory gold minerals by ozonation …
— Pretreatment using microwave-assisted roasting with NaClO 3 as an additive to the oxidizing agent is a new method of processing refractory gold ore. Oxidation was …
Exploring Non-ammoniacal Thiosulfate Gold Leaching and Limited Gold
— The application of pressure oxidation (POX) followed by thiosulfate gold leaching is an efficient method used to extract gold from double refractory gold ores containing both sulfide and carbonaceous matter. This process is expected to result in high gold recovery rates, as it liberates gold from sulfides and eliminates the preg-robbing …
Microwave Pyrolysis Pretreatment of High Arsenic Refractory Gold …
— The process optimization and mechanism of microwave pyrolysis in a nitrogen atmosphere were studied to improve the gold leaching rate for high-arsenic-refractory gold sulfide resources, mainly containing minerals of elemental sulfur, dense pyrite, and arsenopyrite. The decomposability was evaluated using thermodynamic and …
Bacterial Leaching as a Pre-treatment Step for Gold Recovery …
— The Bacterial Oxidation (BIOX) process for the pre-treatment of refractory ores for gold recovery developed by Genmin, the mining division of Gencor, has been operating successfully at the ...
Pretreatment of refractory gold minerals by …
— The problems during the leaching of gold show the necessity for ore pretreatment to minimize the gold entrapment with refractory minerals and solve the gold low recovery challenge from surrounding …