Gold metallurgy is a technology for extracting gold and its compounds from gold ore, gold concentrate, or other gold-bearing materials. Gold is one of the earliest …
Firstly, the dissolution rate of gold during chlorination is much faster than with cyanidation. Secondly, carbonaceous ores are more amenable to chlorination. Finally, the reagent cost (1.5 $/t ...
The samples from three areas studied consisted of: (a) the massive sulfide deposit from Commonwealth Main with high gold (2.41–11.6 g/t), silver (545–1080 g/t), zinc (6.6–10 wt%) and lead (2 ...
Gold, a significant precious metal, has high corrosion resistance, excellent electrical and thermal conductivity [].In the field of gold extraction and smelting, refractory gold ore is one of the most important gold resources at present [].Approximately 30% of the world's gold production is derived from refractory gold ore, and this proportion is …
The paper presents an overview of bio-oxidation of sulphidic refractory gold ores prior to gold cyanidation. This review discusses several factors, more importantly, oxygen requirements and oxygen ...
A "refractory" gold ore is an ore that has ultra-fine gold particles disseminated throughout its gold occluded minerals. These ores are naturally resistant to recovery by standard cyanidation and carbon adsorption processes. ... Bio-oxidation involves the use of bacteria that promote oxidation reactions in an aqueous environment. Pressure ...
Alkaline pressure oxidation is currently being used at the Barrick Mercur Gold Mine, Utah. The operating conditions at Mercur are 220° c and up to 460 psig pressure and pH between 7 and 9, for treating ore with 1 to 2% sulfur and 2g/mt Au (White, 1990). Recently, electrochemical studies on arsenopyrite oxidation in alkaline media …
The alkaline oxidative leach pretreatment for gold-bearing arsenopyrite ores uses mild conditions, and the leach residue requires no washing or pH adjustment before cyanidation. By using 2M NaOH, 100° C, 40 psig O2, 10 pct solids, and 4 h, more than 90 pct of the arsenic was extracted from the high-grade ore.
Typically, gold is encapsulated or finely disseminated in refractory gold ores and the direct cyanidation is not effective for gold extraction from these ores, even after the ore is ground to exceeding small particles (Nazari, 2017, Corrans and Angove, …
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 …
The method uses a reduction-oxidation reaction to selectively extract gold and platinum group metal ions from a liquid containing dissolved electronic waste. In the lab, the team dissolved catalytic …
Oxidation roasting is one of the most effective methods to remove carbonaceous matter from carbonaceous gold ore. However, the consolidation of calcine is a common problem caused by a large amount ...
68 T.O. Nunan et al. / Minerals Engineering 108 (2017) 67–70 Usually the kind of gold ores containing sulphidic minerals – depending on the sulphide content and mineralogy – can be pre-treated by oxidation steps prior to cyanidation, converting the sulphides to oxides or sulphates, in some cases enhancing the opening up of the ore.
Biotechnology offers promising options to recover desired precious metals, such as gold from refractory ores and complex structures (Bal et al. 2019; Ghosh et al. …
It can be illustrated that the pre-oxidation of the gold ore by Mn-oxide oxidation controlled Au-extraction efficiency, and with the dissolution of 93.3 % As and 92.5 % Sb from the gold ore in the usage of Mn-oxide-assisted hydrochloric acid oxidation process, it obtains Au extraction ratio of 97.2 % by chlorination leaching.
High-pressure oxidation comprises the oxidisation of sulphide/carbonaceous gold ore at high pressure and temperature. Temperatures exceeding 200 °C and oxygen pressures above 2200 kPa are used to attain complete oxidation of the gold-bearing ore. Reaction rates can be very fast, and the technology is widely-accepted.
Pressure oxidation is a widely accepted method to treat refractory gold ores. Gold recovery is generally lower from alkaline than acidic pressure oxidation …
of the as-received DRGO yielded only 28.7% gold extraction, which was due to the encapsulation of sulfides on gold and the gold adsorption of CM. After bio-oxidation, thiourea leaching of the DRGO resulted in gold extraction of over 75–80%. Moreover, bio-oxidation can e ectively reduce the adsorption of carbon to gold.
The microwave roasting of a double refractory gold ore was investigated. The TGA results showed that the three major reactions involved in the roasting process were; oxidation of pyrite, oxidation of the carbonaceous matter and the decomposition of carbonates. Both the real and the imaginary permittivities of the ore were relatively low …
Refractory gold ore is usually affected by the associated carbonaceous matter through the preg-robbing effect, which is eliminated by oxidation roasting, followed by leaching, to achieve a satisfactory …
Gold is a strategic mineral resource with financial attributes. China's gold consumption has remained the world's largest for consecutive years, and its production has ranked …
The complex mineralogy of the Porgera resource has a pronounced effect on process selection for the recovery of refractory gold and silver. Intimate association of gold with pyrite necessitates a high degree of sulphur preoxidation to achieve acceptable levels of gold recovery. Acid pressure oxidation has been demonstrated to be the only …
DOI: 10.1016/J.MINENG.2021.106822 Corpus ID: 233530449; Recovery of gold from sulfide refractory gold ore: Oxidation roasting pretreatment and gold extraction @article{Qin2021RecoveryOG, title={Recovery of gold from sulfide refractory gold ore: Oxidation roasting pretreatment and gold extraction}, author={Hong Qin and Xueyi …
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 …
The global approach toward growth and development of industries is driving the increase in demand for precious metals such as gold (Street et al. 2015; Qin et al. 2023).Furthermore, the global gold reserves of ore types that can be processed more facilely are becoming exhausted (Oktay et al. 2016)plex ore deposits or …
Carbonaceous sulfidic gold ores are commonly double refractory and thus require pretreatment before gold extraction. In this paper, the capacity of pre-bio-oxidation can simultaneously decompose sulfides or deactivate carbonaceous matters (CM) from a double refractory gold ore (DRGO) using pure cultures of A. ferrooxidans or L. …
In a study by Xu et al. [24], the gold extraction from ore after the oxygen pressure alkaline leaching reached 78%. From the results by Fraser et al. [25], the number of necessary processing circuits for refractory gold pressure oxidation is dependent on the size of the selected autoclave. It can dramatically affect the pressure oxidation ...
Most gold deposits occur associated with sulphides like pyrite and arsenopyrite; thus, precious metal dissolution is possible by oxidizing auriferous sulfide concentrate using simultaneous pressure oxidation and cyanidation. The effectiveness of this process of extraction can be influenced by the temperature, cyanide (NaCN) …
the aim of the present work is to study a pretreatment with. nitric acid as an alternative to improve the recov er y of gold. from ores associated with gold and gold-silver tellurides. 2 Materials ...
Without pre-oxidation at higher dissolved oxygen levels, the gold cannot be amenable to cyanidation at a cost-effective rate, and thus pre-oxidation of the ore has been a crucial factor in current ...
Gold metallurgy is a technology for extracting gold and its compounds from gold ore, gold concentrate, or other gold-bearing materials. Gold is one of the earliest metals discovered and used, and its element symbol comes from the Latin aurum, with the original meaning "the glorious dawn". ... pressure oxidation, and bacterial oxidation ...
gold (Au), chemical element, a dense lustrous yellow precious metal of Group 11 (Ib), Period 6, of the periodic table of the elements. Gold has several qualities that have made it exceptionally valuable throughout history. It is attractive in colour and brightness, durable to the point of virtual indestructibility, highly malleable, and usually ...
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 …
Moreover, thermal activation pretreatment of this sulfide gold ore significantly enhances the oxidation capacity and results in the generation of sufficient thiosulfate (286 mM). The pretreatment also breaks down the sulfide inclusions to expose the encapsulated gold, which can be in situ extracted via self-generated thiosulfate. ...
The chemical composition of the gold ore samples is presented in Table 1.The Au content is relatively low at 2.13 ppm, and Ag is 35.05 ppm. Previous studies have shown that the gold content in the ore varies between 0.04 and 2.18 ppm (Purwanto et al., 2020).Fe content is the highest metal element, with 22.75 ppm (2.28 %) and a total …
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 …
Oxidation roasting is one of the most effective methods to remove carbonaceous matter from carbonaceous gold ore. However, the consolidation of calcine is a common problem caused by a large amount ...
With the exhaustion of easily recoverable gold ore resources in recent years, carbonaceous gold ore resources have gradually become the main direction of gold mining (Espitia and ... Recovery of gold from sulfide refractory gold ore: Oxidation roasting pretreatment and gold extraction. Miner. Eng., 164 (2021), p. 106822, …
This section first explored the generation of thiosulfate from sulfide gold ore by alkaline oxidation at atmospheric pressure. Notably, as a comparison experiment, the generation of thiosulfate from pyrite concentrate was also studied under the same oxidation conditions (40 and 80 °C) to scientifically identify the sulfur conversion …
