PDF Establishing thE ProcEss MinEralogy of gold orEs

In gold ores, pyrite and arsenopyrite often occur in three morphological types: coarse, porous (blastic) and fine-grained. Framboidal and microcrystalline pyrite are also observed in some gold deposits. Generally, the order of concentration of gold in pyrite and arsenopyrite is: fine-grained>porous>coarse-grained (Figures 8 & 9). In some

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Pyrite−Arsenopyrite Galvanic Interaction and Electrochemical

Comparative voltammetric studies were performed between high purity pyrite mineral (98.86%) and arsenopyrite mineral (content of 85.96% arsenopyrite, FeAsS; 11.84% pyrite, FeS2; 0.98% galena, PbS; 0.06% chalcopyrite, CuFeS2) in order to analyze the galvanic effect on the electrochemical reactivity of two different mineralogical phases when these are associated in the same mineral, using carbon ...

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Migration of arsenic(III) during bacterial oxidation of

During bacterial oxidation of the arsenopyrite that contaminated a chalcopyrite concentrate, the bioextraction of arsenic from the concentrate was examined. A long-term constant As(III) concentration, representing a large portion of the total arsenic, occurred in the leaching medium. As(III) was not further oxidized, either under bioextraction conditions or by Fe(III) in the presence of the ...

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PDF Leaching of the arsenopyrite/pyrite flotation concentrates

LEACHING OF THE ARSENOPYRITE/PYRITE FLOTATION CONCENTRATES 9 Drawing parallels with the pyrite/iron system and the pyrite/sphalerite system, it can be concluded that iron dissolution is supported by the hydrogen evolution reaction on the inert pyrite mineral particle surface.

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Improvements in gold ore cyanidation by pre-oxidation with

The pyrite and arsenopyrite oxidation levels after 240 h were 60.2% and 92.0%, and the gold recovery level by carbon-in-pulp cyanidation was 65.7%. ... leaching of the concentrate by a ...

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The mechanisms of pyrite oxidation and leaching: A

294 A.P.Chandra,A.R.Gerson/SurfaceScienceReports65(2010)293–315 4. Spatiallyresolvedsurfacecharacterisation.....308 ...

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Gold and silver recovery by cyanidation of arsenopyrite ore

--The arsenopyrite matrix, the pyrite, iron arsenate and bismuth do not appear to be attacked by the leaching agent. LEACHING STUDY Materials and procedureThe ore samples used and their composition have been described above. Samples for studies of leaching in cyanide solution were prepared by crushing and grinding in a laboratory ball mill and ...

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CN100485059C - Method for recovering gold from sulphide

The invention relates to a method for recovering gold from a sulphidic concentrate, particularly one containing arsenopyrite and/or pyrite, hydro- metallurgically. The concentrate is first subjected to leaching with a concentrated solution of alkali chloride and copper (II) chloride, by means of which the copper minerals and some of the gold in the concentrate are made to dissolve.

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Biooxidation of a gold-bearing pyrite-arsenopyrite

The specific rates of bioxidation of pyrite and arsenopyrite were very similar for the bulk concentrate at about 0.15 day −1. However, it was significant that the biooxidation of arsenopyrite in the mixed mineral preceded that of pyrite, suggesting a sequential mechanism.

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Arsenopyrite | Scientific.Net

Journal of Biomimetics, Biomaterials and Biomedical Engineering

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Potential Role of Thiobacillus caldus in Arsenopyrite Bioleaching

The third hypothetical mechanism by which T. caldus affects arsenopyrite leaching is the production of surface-active agents to solubilize the S 0. The yeast extract may act as a wetting agent to allow S 0 to be dispersed in the medium, thereby allowing further oxidation of the mineral.

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Establishing thE ProcEss MinEralogy of gold orEs

In gold ores, pyrite and arsenopyrite often occur in three morphological types: coarse, porous (blastic) and fine-grained. Framboidal and microcrystalline pyrite are also observed in some gold deposits. Generally, the order of concentration of gold in pyrite and arsenopyrite is: fine-grained>porous>coarse-grained (Figures 8 & 9). In some

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PRESSURE OXIDATION OF PYRITE-ARSENOPYRITE

leaching the host mineral must be broken by mechanical or chemical means. The aim of this study was to study the effect of temperature, oxygen partial pressure and slurry density on pressure oxidation of pyrite-arsenopyrite gold

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Leaching of the arsenopyrite/pyrite flotation concentrates

The data in Figure 2 show the variation of arsenopyrite/pyrite decomposition with pH at an iron to concentrate ratio of 0 and set leaching temperature of 105°C. The results exhibit an inverse near linear relationship between arsenopyrite/pyrite decomposition and pH.

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Arsenopyrite Mineral | Uses and Properties

Arsenopyrite often oxidizes to form scorodite, a hydrated iron arsenate mineral with a chemical composition of FeAsO 4. 2H 2 O. Scorodite often weathers to limonite, an amorphous, hydrated iron oxide of variable composition.

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