Sulphide ores

Similar graphs can be plotted for the reduction of any metal oxide and also for the reduction of chloride and sulphide ores. 

The principal ore of lead is galena, PbS. Although there are some galena deposits in Great Britain, much of this country s requirements must be imported. In the extraction of lead, the sulphide ore is first roasted together with quartz in a current of air ... 

Each of these elements occurs naturally as a sulphide ore arsenic as realgar As S,, orpiment As, Sg and arsenical pyrites with approximate formula FeAsS antimony as stibnite Sb2S3 and bismuth as B12S3. 

The method of extraction is similar for each element involving first the roasting of the sulphide ore when the oxide is produced, for example... 

Selenium and tellurium occur naturally in sulphide ores, usually as an impurity in the sulphide of a heavy metal. They are recovered from the flue dust produced when the heavy metal sulphide is roasted. 

Since arsenic is often found in nature associated with sulphide ores, sulphur dioxide obtained by this method may contain some arsenic(III) oxide as impurity, and in certain processes this is a distinct disadvantage. 

Oxidation of complex sulphide ores — competitive oxidation of cations... 

T1(I), Pb(II) and Bi(III) are mainly found in natural minerals predominantly in the form of sulphide ores and rarely as sihcates [20, 21]. 

Zhang, Y. Fang, Z. H. Muhammed, M. On the solution chemistry of cyanidation of gold and silver bearing sulphide ores. A critical evaluation of thermo dynamic calculations. Hydrometallurgy 1997, 46, 251-269. 

High concentrations of lead were detected in the wine-coloured and black shales of the Volcanic Sedimentary Complex with 96 mg kg 1 and 52 mg kg"1, respectively. The highest concentrations were reported for the Cu-Pb-Zn massive sulphide ore samples from the abandoned mines of Cabezas del Pasto, Romanera and Serrencillas where concentrations of Pb exceeded 5000 mg kg"1. 

Hydrometallurgical methods are normally employed for recovery of gold from oxidized deposits (heap leach), low-grade sulphide ores (cyanidation, CIP, CIL) and refractory gold ores (autoclave, biological decomposition followed by cyanidation). 

Flotation of Gold From Base Metal Sulphide Ores... 

FLOTATION OF GOLD FROM BASE METAL SULPHIDE ORES... 

In this area, the PGM are distributed in (a) disseminated sulphides, mostly in pyrrhotite, chalcopyrite and pentlandite. The predominant platinum minerals are Pt-Fe alloys, cooperate (PtS) and sperrilite (PtAs2) (b) massive sulphide ores where the predominant PGM are Pt-Fe alloys, rustenburgite (Pt3Sn) and sperrilite (PtAs2), occurring in fine inclusions in chalcopyrite and pyrrhotite and finally (c) disseminated veins and brecia ores that may consist of mainly chalcopyrite or pyrrhotite. The PGM in these ores is present as Pt-(cooperate) and Pd-(rysotkite) sulphides. 

Tenorite (CuO Cu = 80%, SG = 6.5) is usually present in mixed copper oxide and sulphide ore. The flotation properties of tenorite are similar to that of cuprite. 

The flotation properties of bronchantite, antlerite and chalcantite were not examined. These oxide minerals are contained in an altered sulphide ore in some deposits in South America and Zambia. 

Most operating plants that treat oxide copper and copper-cobalt ores are found in Central Africa and Southern Africa regions. A few operations exist in Chile, Brazil and Peru, where they treat mixed oxide sulphide ores or oxide copper gold ore. 

These ore types are abundant in Northern Canada and Mexico. Extensive research work was carried out on these ores with the objective of developing a treatment process for commercial application. One of the major tasks in the development testwork was to use a non-cyanide flotation method in the sulphide flotation. Typical reagent schemes used in beneficiation of the mixed lead zinc oxide sulphide ores are shown in Table 20.5. 

The flowsheet used for beneficiation of mixed oxide sulphide ore is illustrated in Figure 20.4. 

Reagent schemes used for mixed lead zinc oxide sulphide ores [10]... 

Bulatovic, S., Process Development for Treatment of Pb/Zn of Oxide Sulphide Ore from Prairie Creek (Canada), Report of Investigation, January 2006. 

Medium-coarse-grained, less-disseminated ores. The size of cassiterite particles in this ore type ranges from 1.0 to 0.2 mm in size. Typical ore bodies of this type are pegmatitic and tin-containing sulphide ores. 

Depending on the composition of disseminated and medium-coarse-grained ore, they can be divided into two basic groups sulphides and chloritic tourmaline ores. In the sulphide ore, the minerals are represented by pyrite, pyrrhotite, arsenopyrite, chalcopyrite, galena and stannin. Less common are sphalerite and bismuth. 

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