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Mineral copper xanthate

The copper sulfide formed on the surface of the sphalerite mineral reacts readily with the xanthate, and forms insoluble copper xanthate, which makes the sphalerite surface hydro-phobic. Such a reaction for activating sphalerite occurs whenever the activating ions are present in the solution. It is thus necessary to deactivate sphalerite (to prevent the occurrence of natural activation) in the case of some ores. With lead-zinc ores, for example, natural activation occurs due to Pb2+ in solution... [Pg.205]

In the 2nd period ranging from the 1930s to the 1950s, basic research on flotation was conducted widely in order to understand the principles of the flotation process. Taggart and co-workers (1930, 1945) proposed a chemical reaction hypothesis, based on which the flotation of sulphide minerals was explained by the solubility product of the metal-collector salts involved. It was plausible at that time that the floatability of copper, lead, and zinc sulphide minerals using xanthate as a collector decreased in the order of increase of the solubility product of their metal xanthate (Karkovsky, 1957). Sutherland and Wark (1955) paid attention to the fact that this model was not always consistent with the established values of the solubility products of the species involved. They believed that the interaction of thio-collectors with sulphides should be considered as adsorption and proposed a mechanism of competitive adsorption between xanthate and hydroxide ions, which explained the Barsky empirical relationship between the upper pH limit of flotation and collector concentration. Gaudin (1957) concurred with Wark s explanation of this phenomenon. Du Rietz... [Pg.1]

Another example is the ethyldiamine used for the activation of flotation of oxidized copper mineral by xanthate. It is believed that the ethyldiamine salt gets adsorbed on copper... [Pg.187]

Lipid-soluble metal complexes such as copper xanthates (from mineral flotation plants), copper 8-hydroxyquinolinate (agricultural fungicide) or alkyl-mercury compounds are particularly toxic forms of heavy metals because they diffuse rapidly through a biomembrane and carry both metal and ligand into the cell. ... [Pg.121]

Copper sulfldes, chalcopyrite, chalcocite, bomite, covellite Pyrite, pyrrhotite, other sulfide minerals, quartz Xanthates, dithiophosphates... [Pg.217]

Figure 27 presents the flotation recovery curves of Richardson and Walker" for chalcocite, bomite, chalcopyrite, and pyrite. The results for chalcocite are similar to those shown in Fig. 25. The onset of flotation of bornite and chalcopyrite was found" to coincide with the potentials at which UV-vis spectroscopy showed xanthate to begin to be abstracted from solution. This indicated that attachment of xanthate to the surface was responsible for inducing flotation for both minerals. As pointed out in Section VII, these potentials are below the values at which copper xanthate or dixanthogen are formed but correspond to values at which chemisorption is expected. Figure 27 presents the flotation recovery curves of Richardson and Walker" for chalcocite, bomite, chalcopyrite, and pyrite. The results for chalcocite are similar to those shown in Fig. 25. The onset of flotation of bornite and chalcopyrite was found" to coincide with the potentials at which UV-vis spectroscopy showed xanthate to begin to be abstracted from solution. This indicated that attachment of xanthate to the surface was responsible for inducing flotation for both minerals. As pointed out in Section VII, these potentials are below the values at which copper xanthate or dixanthogen are formed but correspond to values at which chemisorption is expected.
The examples in the preceding section, of the flotation of lead and copper ores by xanthates, was one in which chemical forces predominated in the adsorption of the collector. Flotation processes have been applied to a number of other minerals that are either ionic in type, such as potassium chloride, or are insoluble oxides such as quartz and iron oxide, or ink pigments [needed to be removed in waste paper processing [92]]. In the case of quartz, surfactants such as alkyl amines are used, and the situation is complicated by micelle formation (see next section), which can also occur in the adsorbed layer [93, 94]. [Pg.478]

Activators promote the reaction of the coUector with some minerals. For example, ordinarily xanthates do not bind to sphalerite, but pretreatment of the sphalerite using copper sulfate enables it to adsorb the xanthate. Thus it is possible to float the sphalerite from lead—zinc ores after the galena has been recovered. [Pg.34]

AEROPHINE 3418A promoter is widely used ia North and South America, AustraHa, Europe, and Asia for the recovery of copper, lead, and ziac sulfide minerals (see Elotatton). Advantages ia comparison to other collectors (15) are said to be improved selectivity and recoveries ia the treatment of complex ores, higher recoveries of associated precious metals, and a stable grade—recovery relationship which is particularly important to the efficient operation of automated circuits. Additionally, AEROPHINE 3418A is stable and, unlike xanthates (qv), does not form hazardous decomposition products such as carbon disulfide. It is also available blended with other collectors to enhance performance characteristics. [Pg.319]

Aetivators. These are used to make a mineral surface amenable to collector coating. Copper ion is used, for example, to activate sphalerite (ZnS), rendering the sphalerite surface capable of absorbing a xanthate or dithiophosphate collector. Sodium sulfide is used to coat oxidized copper and lead minerals so that they can be floated by a sulfide mineral collector. [Pg.1809]

The flotation of sphalerite, the sulfidic mineral source of zinc, is next considered as an example to illustrate the role of activators. This mineral is not satisfactorily floated solely by the addition of the xanthate collector. This is due to the fact that the collector products formed, such as zinc xanthate, are soluble in water, and so do not furnish a hydrophobic film around the mineral particles. It is necessary to add copper sulfate which acts as an... [Pg.204]

The products of hydrolysis and dissociation depend on the pH. In an acid medium, hydrogen sulfide, which has no depressing action, evolves. It is, therefore, necessary to use alkaline circuits in which HS, predominates. These sulfide ions are adsorbed on the copper sulfide mineral surface and react with the surface previously coated with cuprous xanthate. The reaction causes desorption of the collector, and as a result of this desorption the copper sulfide minerals generally become hydrophilic. There is, however, no action of the sulfide ions on molybdenite, and so molybdenite retains its hydrophobic character. [Pg.205]

The most preferred sulphidizer used in flotation of oxide copper minerals is Na2S 9H20. Other sulphidizers used in operating plants include NaHS and (NH4)2S. Actually, the selection of a sulphidizer is based on the consumption required for flotation of oxide copper from particular ore types. For example, in some cases the consumption requirement of NaHS is much higher than for Na2S. Figure 19.5 shows the effect of different levels of sulphidizer on the recovery of malachite using xanthate collector. [Pg.53]

As mentioned earlier in this chapter, the choice of collector is very much dependent on the type of copper minerals, as well as the type of gangue minerals present in the natural ore. If the ore contains siliceous gangue minerals, then various fatty acid modifications can be used as the principal collector in plant practice. Ores containing carbonaceous and dolo-mitic gangue minerals, where sulphidization method is used, xanthate collector is used as... [Pg.55]

Xanthated fatty acid mixture is a new line of collectors, specifically designed for beneficiation of oxide copper ores that contain dolomitic and carbonaceous gangue minerals [19]. This collector was developed after extensive laboratory development testwork. The effectiveness of this collector was compared to a standard xanthate collector in a series of continuous locked cycle tests (Table 19.5). [Pg.57]

Abstract In the beginning, the mixed potential model, which is generally used to explain the adsorption of collectors on the sulphide minerals, is illustrated. And the collector flotation of several kinds of minerals such as copper sulphide minerals, lead sulphide minerals, zinc sulphide minerals and iron sulphide minerals is discussed in the aspect of pulp potential and the nature of hydrophobic entity is concluded from the dependence of flotation on pulp potential. In the following section, the electrochemical phase diagrams for butyl xanthate/water system and chalcocite/oxygen/xanthate system are all demonstrated from which some useful information about the hydrophobic species are obtained. And some instrumental methods including UV analysis, FTIR analysis and XPS analysis can also be used to investigated sulphide mineral-thio-collector sytem. And some examples about that are listed in the last part of this chapter. [Pg.63]

The influence of copper ion on the flotation of zinc-iron sulphide minerals in the presence of depressant with butyl xanthate l.Ox 10 mol/L as a collector is presented in Fig. 6.11 to Fig. 6.14. It can be seen from Fig. 6.11 and Fig. 6.12 that in the presence of 120 mg/L 2-hydroxyl ethyl dithio carbonic sodium (GXl) and 2,3 dihydroxyl propyl dithio carbonic sodium (GX2), marmatite is activated by copper ion and exhibits very good flotation with a recovery above 90% in the pH range of 4-8. The flotation of arsenopyrite and pyrrhotite is poor with a... [Pg.152]

Miner. Process Extra. Metall. Rev., 2 203 - 234 Hayes, R. A. and Ralston, J., 1988. The collectorless flotation and separation of sulphide minerals by control. Inter. J. Miner. Process, 23 55 - 84 Hepel, T. and Pomianowski, A., 1977. Diagrams of electrochemical equilibria of the system copper-potassium ethyl xanthate-water at 25°C. Int. J. Miner. Process, 4 345 - 361 Heyes, G. W. and Trahar, W. J., 1977. The natural floatability of chalcopyrite. Int. J. Miner. Process, 4 317-344... [Pg.274]

Pozzo, R. L., Malicsi, A. S., Iwasaki, L, 1988. Pyrite-pryyhotite-grinding media contact and its effect on flotation. Minerals Metallurgical Processing, 5(1) 16-21 Pozzo, R. L., Malicsi, A. S., Iwasaki, I., 1990. Pyrite-pyrrhotite-grinding media contact and its effect on flotation. Minerals Metallurgical Processing, 7(1) 16 - 21 Prestidge, C. A., Thiel, A. G., Ralston, J., Smart, R. S. C., 1994. The interaction of ethyl xanthate with copper (II)—activated zinc sulphide kinetic effects. Colloids Surfece, A. Physicochem. Eng. Aspects, 85 51 - 68... [Pg.279]

Woods, R., 1996. Chemisorption of thiols on metal and metal sulphide. In J. O M Bockris, B. E. Conway, R. E. White (eds.). Modem Aspects of Electrochemistry. 29 401 - 453 Woods, R., Young, C. A., Yoon, R. H., 1990. Ethyl xanthate chemisorption isotherms andEh-pH diagrams for the copper/water/xanthate and chalcocite/water/xanthate systems. Inter. J. Miner. Process, 30 17 - 33... [Pg.283]

Depressants (or deactivators) are chemicals that ensure that undesired particles remain hydrophilic and therefore do not get floated. Conversely to the activation of zinc sulfide by copper ions above, zinc ions from zinc sulfate act as a depressant for zinc sulfide. Another example is the use of cyanide to complex with copper and prevent adsorption of collectors in the flotation of base-metal sulfides with xanthates. There are many other depressants but they tend to be quite specific to one of a few types of minerals. In some cases, such as some uses of cyanide as a depressant, the mechanism of depressant action remains unclear. [Pg.251]

Quite frequently the natural surface of a mineral requires preliminary chemical treatment before it will form the surface film required for collection One of the commonest instances of this is with sphalerite (zinc sulphide), which does not float properly when treated with xanthates. If, however, it is given a preliminary treatment with dilute copper sulphate solution, a very small amount of copper sulphide is deposited on the surface and the ore becomes floatable, the surface being now capable of reaction with xanthates. Such treatment is usually termed activation in general, an activating solution for a sulphide mineral should contain a metallic ion whose sulphide is less soluble than that contained in the mineral for zinc sulphides, silver, copper, mercury, cadmium, and lead salts are all effective activators. [Pg.197]


See other pages where Mineral copper xanthate is mentioned: [Pg.397]    [Pg.569]    [Pg.423]    [Pg.477]    [Pg.411]    [Pg.204]    [Pg.5]    [Pg.47]    [Pg.15]    [Pg.67]    [Pg.126]    [Pg.154]    [Pg.155]    [Pg.158]    [Pg.158]    [Pg.251]    [Pg.273]    [Pg.277]    [Pg.278]    [Pg.283]    [Pg.283]    [Pg.283]    [Pg.311]    [Pg.256]    [Pg.29]    [Pg.197]   
See also in sourсe #XX -- [ Pg.111 ]




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Copper xanthate

Minerals copper

Xanthates

Xanthation

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