To provide a theoretical basis for a suitable process to extract gold from refractory gold concentrates, process mineralogy on the acid leaching residue of gold calcine was studied by chemical composition, X-ray diffraction, scanning electron microscopy-energy spectrum, and mineral dissociation analysis. The results showed …
Gold is mainly present in the form of [Au(CN)2]− during the cyanide leaching process, and this [Au(CN)2]− can be adsorbed by graphite in carbonaceous gold ore resulting in preg-robbing gold.
The nitric acid pre-treatment experiments for refractory silver ore and gold/silver concentrate were performed for 2.5 hours at 5M HNO 3 and 80 o C. Before and after nitric acid pretreatment ...
Refractory gold reserves, which require more sophisticated treatment methods in order to achieve oxide-ore recovery rates, correspond to 24 percent of current gold reserves and 22 percent of gold resources …
The depletion of readily amenable gold ores and discovery of complex dep osits inspire. knowledge improvement and search of commercially effective te chnique in extracting gold from refractory ...
The problems during the leaching of gold show the necessity for ore pretreatment to minimize the gold entrapment with refractory minerals and solve the …
In the pre-leach stage, the release of arsenic increased for the experiments with the lon-ger contact time (48 h) and higher hydroxyl ion concentration (3 M). In Fig. 8, the dissolved arsenic ...
In order to render gold amenable to the subsequent cyanide leaching, oxidation pretreatment is considered to be an effective method for treatment of refractory gold ore, and breaks up the sulphide ...
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 …
In addition the paper describes the various pre-cyanidation treatment methods for carbonaceous refractory gold ores namely, (1) flotation and depression, (2) blanking, (3) the use of activated carbon or resin in leach, (4) roasting, (5) chemical oxidation and (6) bioleaching. Previous. Next.
Selective alkaline leaching of antimony from Low-grade refractory gold ores and process optimization. October 2023. Minerals Engineering 201 (2):108198. DOI: 10.1016/j.mineng.2023.108198. Authors:
In this study, a new method to improve gold extraction from sulfide bearing gold ores is proposed based on the model experiments using a mixture of gold powder and arsenopyrite-bearing sulfide (HAsBS) ore. The effects of HAsBS ore on gold leaching in ammonium thiosulfate solutions were investigated, and it was found that gold extraction …
Copper–cobalt sulfide flotation concentrate received from Comika Mining Kamoya project in Congo contains around 24.2% copper, 7. ... Pretreatment of refractory gold ore by curing with concentrated sulfuric acid. Yisa Liu Kang Li ... Use of dry grinding process to increase the leaching of gold from a roasted concentrate containing …
For the refractory gold–silver ores associated with manganese minerals, this study has developed a reductive sulfating leaching pretreatment process to dissolve manganese minerals before gold–silver cyanidation, and pyrite has been proved that could be used as an effective reductant in the pretreatment step.
Introduction. 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 first in the world for 10 years. 1,2 However, the amount of easily exploited high-grade gold ores has rapidly decreased. Thus, the gold ore associated …
The application of roasting pretreatment for antimonial refractory gold and silver ores, XXV. International Mineral Processing Congress, Brisbane, Australia, pp. 1505–1510. Celep, O., Alp, İ., Deveci, H., 2011. Improved gold and silver extraction from a refractory antimony ore by pre-treatment with alkaline sulphide leach.
This paper will review some of the existing techniques and operations that are being used for the treatment of refractory gold ores, with particular emphasis on the …
the refractory gold ore and is the accomplished process, and the operation is simple, but the gold leaching rate is not high and the cost of waste gas treatment is expensive [12, 13].
Following pretreatment, refractory gold ores are leached in order to extract gold. Currently, the leaching agents are separated into two groups: cyanide and non …
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 …
Qiu et al. [15] developed a cyanidation process with a pretreatment stage for silver and gold recovery from a refractory Au-Ag ore. The pretreatment used pyrite as a reductant where MnO 2 was ...
The pretreatment of refractory gold ore is a complex chemical process. In addition to the oxidation of pyrite, some side reactions also occur. The phase changes of refractory gold ore before and after pretreatment are shown in Fig. 11. The main phases of refractory gold ore include quartz (SiO 2), pyrite (FeS 2), and dolomite (CaMg(CO …
pretreatment of refractory ores in gold leaching In this way, gold recovery from refractory minerals can increase from 1530% to 8595% In the last 15 years at . ... Functional Mobile Impact Crusher can process mediu... More Mobile Primary Jaw Crusher... Mobile Primary Jaw Crusher Exchange system, Pre screening function Since …
Sulfide gold ores account for a large proportion of refractory gold ores, therefore, it is very meaningful to recover gold from sulfide gold ores (Ubaldini and Vegliò, 2000; Saba, 2011; Hammerschmidt, 2016). Moreover, the major gold leaching process for extracting gold from ores and concentrates is still cyanide leaching.
CHAPTER 5. Heap Leaching of Gold-Bearing Deposits: Theory and Operational Description. James A. Brierley. Introduction. Biooxidation. pretreatment of refractory …
stirring was continued for 30 min. Gold leaching lasted 24.0 h with a concentration of 0.3% NaCN. The leaching residue was filtered and dried before measuring the gold grade. The leaching rate of gold (η) is calculated as follows29,36 η 1 θ β =− × i k jj jj y {zz zz (2) where η is the leaching rate of gold, β is the gold grade of
In this study, the extraction of gold from a copper-bearing gold ore by ammoniacal cyanide leaching was studied. Furthermore, ammonia leaching as a pretreatment process ahead of cyanide leaching was also examined. Only ~12% of gold was extracted by direct cyanide leaching of the ore. The addition of lead nitrate did not affect the leaching of …
In order to achieve efficient gold recovery from the refractory gold ores, an effective pretreatment process of refractory gold ore has become a necessity [19][20][21]. ...
Download Citation | On Jul 1, 2023, Qihao Gui and others published Oxidative pretreatment of refractory gold ore using persulfate under ultrasound for efficient leaching of gold by a novel eco ...