Products

alkaline oand idation refractory gold

[PDF] OXIDATION OF REFRACTORY GOLD CONCENTRATES AND

Jan 01, 2004· The alkaline oxidation of refractory gold concentrates containing arsenopyrite and pyrite at ambient temperatures and pressures has been found to be accompanied by the simultaneous dissolution of gold without the addition of cyanide. A detailed study has been made of the kinetics of the oxidation of the pure minerals and of several concentrates.

More

Alkaline-Related Gold Systems: An Overview Seeking Alpha

Jul 15, 2019· Gold to silver ratio is much lower in alkaline porphyry systems than in alkaline epithermal systems. Alteration includes potassium, sodium, propylitic, and magnetite replacement (Fig. 3). Fig. 3.

More

Alkaline and acidic autoclaving of refractory gold ores

Feb 01, 1991· American Barrick operates two autoclaves for the processing of refractory gold ores. Because of the mineralogy of the ores, one autoclave is alkaline and the other acidic. The pH of operation has a significant effect on materials of construction, as well as capital and operating costs. The following summary concentrates on the practical and economic aspects of such operations.

More

Oxidation of refractory gold concentrates and simultaneous

The oxidation of refractory gold concentrates containing arsenopyrite and pyrite and the simultaneous dissolution of gold in aerated alkaline solutions at ambient temperatures and pressures without the addition of cyanide has been studied. It involves the following aspects: the chemistry of the oxidation of pure arsenopyrite and pyrite minerals in aerated alkaline solutions; the kinetics of

More

Atmospheric alkaline pre-oxidation of refractory sulphide

Four iron-sulphide-containing gold ores from the White Mountain mine in the Jilin Province, China were studied to examine the benefits of using oxidative treatment prior to conventional cyanidation to leach gold. This pre-treatment consisted of bubbling air into an ore/water mixture for eight hours while adding enough caustic sodium hydroxide to maintain a pH of 11 throughout the test. Three

More

OXIDATION OF REFRACTORY GOLD CONCENTRATES AND

ammonia. The leaching experiments also have shown that gold may dissolve in alkaline thioarsenite solutions, which provides a possible new process option for the leaching of gold. The oxidation of refractory arsenical gold concentrates in aerated alkaline solutions results in the formation of thiosulfate, arsenate and sulfate as well as the

More

Gold Deposits Related to Alkaline Magmatism Gold in 2000

Alkaline porphyry-style systems in which SiO 2 < 60 wt percent tend to develop deposits rich in Cu and platinum-group elements (PGE), whereas more felsic systems were enriched in Mo, and ultimately, F, Be, Hg, W, and Sn in the most evolved systems. Alkaline gold deposits also exhibit distinctive metal ratios and

More

Alkaline Oxidative Leaching of Gold-Bearing Arsenopyrite Ores

emissions and is suitable for small gold producers. Demopoulos and Papangelakis have reviewed the recent development of hydrometallurgical oxidation processes and their possible applications to treat refractory gold ores (5). These processes can be classified as pressure oxidation (6), biological oxidation (7), and chemical oxidation (8).

More

gold refractory,ore classification,preprocessing methods

The reasons of gold refractory, ore classification, and preprocessing methods. I. The reason of the gold mineral refractory. There are so many types of reasons that caused the difficulty of gold ore processing, including physical element, chemical element, and mineralogical element. In summary, the difficulties consist of the following

More

Extraction of Gold from a Low-Grade Double Refractory Gold

The concentrate from the flotation procedure was processed using different preoxidation methods. A concentrate containing 34.08g/t of gold with the gold recovery ratio of 81.20% was obtained by flotation. After roasting, microwave heating or alkaline pressure oxidation, the gold cyanidation ratio reached 82.37%, 81.26% and 71.09% respectively.

More

Alkaline and acidic autoclaving of refractory gold ores

American Barrick operates two autoclaves for the processing of refractory gold ores. Because of the mineralogy of the ores, one autoclave is alkaline and the other acidic. The pH of operation has a significant effect on materials of construction, as well as capital and operating costs. The following summary concentrates on the practical and economic aspects of such operations.

More

Neutral and alkaline bio-heap oxidation of refractory gold

Neutral and alkaline bio-heap oxidation of refractory gold ores with adaptive moderate-thermophilic and mesophilic microorganisms. The project has been defined to address the growing concerns of the mining industry towards sustainable copper production with low cost and environmentally friendly process option. The current processes for copper

More

Oxidation of Refractory Gold Concentrates and Simultaneous

The oxidation of refractory arsenical gold concentrates in aerated alkaline solutions results in the formation of thiosulfate, arsenate and sulfate as well as the dissolution of gold, copper and iron.

More

The Albion Process for Refractory Gold Core Resources

Where the main gold bearing refractory mineral in the concentrate is pyrite, the oxidative leach is typically carried out under alkaline conditions. The leach conditions are set to ensure the formation of goethite as the major iron reaction product. The alkaline leach conditions accelerate the rate of

More

The reasons of gold refractory, Gold ore classification

Nov 28, 2016· The reason of the gold mineral refractory There are so many types of reasons that caused the difficulty of gold ore processing, including physical element, chemical element, and mineralogical element.

More

Extraction of Gold from a Low-Grade Double Refractory Gold

The concentrate from the flotation procedure was processed using different preoxidation methods. A concentrate containing 34.08g/t of gold with the gold recovery ratio of 81.20% was obtained by flotation. After roasting, microwave heating or alkaline pressure oxidation, the gold cyanidation ratio reached 82.37%, 81.26% and 71.09% respectively.

More

An Investigation of the Role of Sodium Carbonate and

Abstract. Pressure oxidation of refractory gold ores containing carbonate minerals is conducted under neutral/alkaline conditions in order to promote fast kinetics, reduced reagent consumption and suppressing the formation of elemental sulphur and CO2 (which reduces the effectiveness of

More

Review of gold extraction from ores ScienceDirect

These options include: ultrafine grinding; acid and alkaline pressure oxidation; and a variety of chemical pretreatments such as: Activox process, HMC process and Electrolytic oxidation process. In Australia, the two pre-eminent options for refractory gold ore pretreatment are roasting and biooxidation and this development is reported.

More

A fundamental study of the alkaline sulfide leaching of gold

where r is the leaching rate (mol/m2s), M is the atomic mass of gold (196.97g/mol), A is the area of the gold electrode (m2), and t is the time elapsed (s). Thus, the slope of the kinetic plot is a measure of the leaching rate. It can be seen from Figure 1 that the gold/silver leach rate increases as a function of time,

More

high pressure oxidation of refractory gold minerals

high pressure oxidation of refractory gold minerals. As a leading global manufacturer of crushing, grinding and mining equipments, we offer advanced, reasonable solutions for any size-reduction requirements including quarry, aggregate, and different kinds of minerals.

More

Alkaline sulfide pretreatment of an antimonial refractory

This paper presents the alkaline sulfide pretreatment of an antimonial refractory gold and silver ore. In the ore, gold occurs mainly as gold-silver alloys and as associated with quartz and framboidal pyrite grains, and, to a small extent, as the inclusions within antimonial sulfides. Silver is present extensively as antimonial sulfides such as andorite.

More

Influence of potassium hydroxide pretreatment on the

Celep et al. (2011a,b) and Alp et al. (2014) increased silver and gold extraction, in a subsequent cyanidation from a refractory antimony ore, using an alkaline pretreatment with Na 2 S and NaOH

More

Alkaline Pre-oxidation for Refractory Gold Arsenosulfide

A new hydrometallurgical pre-oxidation process for the refractory gold arsenosulfide concentrates under normal temperature and pressure was presented. It comprised fine grinding, intensified agitation alkali-leaching, cyanidation and adsorption. In a stirring-type pulverizing-leaching tower mill, the concentrate was ground to 37μm of 98 %, then the intensified alkaline leaching for 24 h by

More

Mineralogy and Pretreatment of a Refractory Gold Deposit

The technological mineralogy of a gold deposit located in North-Western province of Zambia was carried out by using X-ray fluorescence spectroscopy (XRF), X-ray diffraction spectroscopy (XRD), and scanning electron microscope (SEM). The results showed that gold was highly dispersed in gold-bearing minerals such as pyrite, arsenopyrite, and some gangues in the form of natural gold and electrum.

More