A novel technique for silver extraction from Ag2S is described. The method utilizes thiosulphate as complexing reagent and the redox reaction between SO2 added as Na2SO3 powder and H2S gas evolved. The parameters of the reaction such as pH, the reaction temperature, the complex equilibrium of Ag ion with thiosulphate and the solubility of Ag2S were investigated. Silver ions, obtained by this me...

An increasing number of low-grade gold ore deposits are characterized by the presence of gold as solid solution into the mineral matrix of sulphide minerals which is not directly amenable to gold cyanidation. In order to liberate this submicroscopic gold the ore has to be oxidized before being subjected to gold cyanidation and exctraction. This is mainly done by autoclave pressure oxidation (AC...

In this work, the dispersive effect of low molecular weight sodium polyacrylate (PAAS) on serpentine, and its dispersion mechanism were systematically investigated through zeta potential measurements, micro and batch flotation as well as adsorption tests. At pH 5, where flotation of iron sulphide was routinely performed, pyrite and serpentine minerals were oppositely charged, and therefore they...

Some idea of the possibilities of microbeam techniques can be illustrated by examining the following example of a run of mine gold ore sample. Milling and bulk chemical analysis of the ore will provide major and minor element analysis as well as the gold grade. More detailed chemistlY can also reveal the presence of trace elements that may be advantageous or deleterious to downstream processing...

The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus t...

Extended ICP-OES and AAS analysis of floated polysulphide concentrate from the Asgat polymetallic ore revealed that contains 0.91% silver, 18.2% copper, 19.4% antimony, 2.03% arsenic 1.6% bismuth together with other elements. The prevailing minerals in are tetrahedrite, bismuthinite, chalcopyrite, arsenopyrite pyrite non-ore i.e. siderite, muscovite quartz. content above was estimated by X-ray ...

Academic insignia of the Faculty Chemical Technology UCT Prague have a history and are used in academic ceremonies (graduation, ceremonial scientific councils, awarding honorary doctorates, etc.). Insignia consists single chain with medal scepter. They made gold-plated silver decorated natural synthetic precious stones. The central motif head sceptre is pentagonal dodecahedron cut from sulphide...