Double refractory gold ores, such as Barrick's Goldstrike ore, contain both pyrite and carbonaceous matter and the latter results in the loss of gold from solution during cyanide leaching. One possible remedy is to roast the ore and thus oxidize the pyrite and remove the organic carbon. In this research, microwave roasting of a double refractory gold …
DOI: 10.1016/J.MINENG.2019.02.037 Corpus ID: 109159359; Extraction of gold from refractory gold ore using bromate and ferric chloride solution @article{Wang2019ExtractionOG, title={Extraction of gold from refractory gold ore using bromate and ferric chloride solution}, author={Qiang Wang and Xianzhi Hu and Futing Zi …
Mechanical (ultra fine grinding P 80 -16µm) and chemical (alkaline, NaOH) pre-treatment and microwave roasting and microwave-assisted cyanide leaching were investigated to increase gold recoveries. Ultrafine grinding was the most effective, producing recoveries of 66.5%. NaOH pre-leaching of ultrafine milled material increased recovery to 71.5%.
Microwave-assisted leaching, as a clean and efficient method of strengthening leaching, has been used in the pretreatment of complex and refractory ores such as chalcopyrite [ 14, 15 ], nickel laterite [ 16, 17 ], and sulfide concentrates [ 18 ]. In this paper, the removal of arsenic from arsenic-bearing gold ore through air oxidation and ...
B. Nanthakumar, C. A. Pickles, and S. Kelebek, "Microwave pretreatment of a double refractory gold ore," Minerals Engineering, 20 (11) (2007), ... "A mechanism study on technology of pretreatment of refractory gold ores by alkaline hot-pressure oxidation," Rare Met, 02 (2003), 249–253. Google Scholar
The effect of microwave roasting pre-treatment on gold extraction was examined. The gold extraction increased to 90% after the ore was microwave roasted for 30 min at 500 °C. ... Yang et al., 2013). Roasting is one of the most effective pretreatment methods for refractory gold ores. The recovery of gold from refractory carbonaceous …
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 difficult processing ores, and about 1/3 total output of world gold is produced from refractory gold. ... Kyuesi and Haque, etc. have studied the role of microwave in ...
The leaching efficiencies of metal ions (As, Cu, Zn, Fe, and Pb) and recovery of gold from refractory gold concentrate were …
Microwave pretreatment: ... Biooxidation (BIOX) pre-treatment of refractory gold concentrates using mixotrophic and chemolithotrophic bacteria on the gold extraction during cyanidation indicated 91.4% gold could be extracted by mixotrophic bacteria for 14 days, and it was 18% higher than the extraction level of direct cyanidation …
Reserves of high-grade gold ore worldwide are decreasing, and some industries have started processing refractory gold ore. Refractory gold ore contains sulfide minerals such as pyrite (FeS2), chalcopyrite (CuFeS2), galena (PbS), and sphalerite (ZnS). Gold in refractory ores occurs as fine-size gold-bearing sulfide minerals. In this …
Microwave energy was applied in the pretreatment of a typical refractory arsenopyritic gold concentrate. More than 80% of As and S were volatilized off as As 2 O 3 and SO 2; whereas iron was oxidized mostly to hematite (Fe 2 O 3).All the gold was present in the calcine which responded favourably to the conventional alkaline …
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 …
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 studied through sulfur and chlorine mass balance analysis and the degree of metal extraction from sulfide minerals.
Microwave pretreatment of gold-bearing sulfides in an inert atmosphere has served as a promising technique to improve the extraction of gold. However, the complex decomposition mechanism of gold-bearing pyrite under microwave irradiation has not been completely clarified. ... Microwave Pyrolysis Pretreatment of High Arsenic Refractory …
Microwave roasting could find application in the minerals industry as a pretreatment method for refractory gold concentrates. Many processing plants, where refractory gold ores are treated, incorporate a flash flotation system where coarse flotation is done and the flash concentrate is milled further in a regrind circuit.
Experimental Study on Microwave Pretreatment with some Refractory Flotation Gold Concentrate. The microwave pretreatment of a typically refractory flotation gold concentrate was investigated. The results demonstrated that a maximum gold recovery of 97% was achieved, and that gold recoveries….
The grade and recovery of gold in the flotation concentrates were 49.44 g/t and 33.36%, respectively. The total recovery of gold was 90.94%. The gravity–flotation combined beneficiation pretreatment process provided a feasible method for the refractory gold ore and ensured the effective recovery of gold.
In this research, we studied the use of microwave pretreatment to enhance the efficiency of Au leaching from gold concentrate. The gold concentrate was pretreated using microwaves with different irradiation time. The sample temperature was increased up to 950 °C by the microwave irradiation. A scanning electron microscope-energy dispersive …
Following pretreatment, refractory gold ores are leached in order to extract gold. Currently, the leaching agents are separated into two groups: cyanide and non-cyanide reagents. ... Pretreatment using microwave-assisted roasting with NaClO 3 as an additive to the oxidizing agent is a new method of processing refractory gold ore. …
NaOH is a powerful tool for gold extraction from refractory tailings. Keywords. gold recovery, refractory calcine tailings, ultrafine grinding, alkaline pre-treatment, microwave. Introduction. South Africa has over 500 gold tailings dumps, several of which have the potential to be profitably . reprocessed (Janse van Rensburg, 2016). Gold lost ...
The results demonstrated that a maximum gold recovery of 97% was achieved, and that gold recoveries of the refractory gold concentrate quickly increased to the maximum with microwave heating time.
In this research, microwave roasting of a double refractory gold ore was investigated as an alternative method and the results were compared to those obtained …
Microwave roasting method was applied for the pretreatment of refractory gold ore (RGO). The occurrence, phase of gold and microstructure of roasted product were analyzed. The results showed that ...
Microwave energy was applied in the pretreatment of a typical refractory arsenopyritic gold concentrate. More than 80% of As and S were volatilized off as As 2 …
Abstract and Figures. In this research, we studied the use of microwave pretreatment to enhance the efficiency of Au leaching from gold concentrate. The gold concentrate was pretreated using ...
In this study, the microwave-assisted roasting method has been investigated as a pretreatment for a refractory gold ore. This method can provide rapid heating radiation, cause micro-cracks, and ...
The cyanide leaching rate of gold was 92.03% by microwave roasting with roasting time of 15 min and roasting temperature at 480°C; and the cyanide leaching rate …
the refractory minerals and minimize all impurities that are harmful to leaching before the gold is leached. The pretreatment of HARGRs includes physical and chemical methods. The physical method involves exposing the locked gold through fine grinding, such as ultrafine grind-ing pretreatment, which involves grinding the gold
Optimizing the alkaline oxidation pretreatment of a refractory gold ore using taguchi orthogonal array method. Foad Mahmoodi1 and Asghar Azizi1. Published 28 …
Request PDF | On Nov 1, 2023, Abdul Hapid and others published Oxidation of sulfide mineral and metal extraction analysis in the microwave-assisted roasting pretreatment of refractory gold ore ...
Microwave Pyrolysis Pretreatment of High Arsenic Refractory Gold Sulfide Concentrates in Nitrogen Atmosphere: Process Optimization and Mechanism Study. …
liberation of gangue minerals on the sulfide surface. The recovery rate of gold in the leach residue. was improved with microwave-assisted leaching, with a gold recovery of ~132.55 g t after 20 ...
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 studied through sulfur and chlorine mass balance analysis and the degree of metal extraction from sulfide minerals.
Oxidation roasting pretreatment is the most common pretreatment approach to treatment refractory gold ores [13,14,15,16,17]. To achieve good recoveries in subsequent leaching, the majority of the sulfur and organic carbon has to be oxidized to SO 2 and CO 2 ; the arsenic of ore has to be transformed to the volatile trivalent compound.