Collectors mineral processing

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]. 

Buckley, A. N., 1994. A survey of the application of X-ray photoelectron spectroscopy to flotation research. Colloids Surf, 93 159 - 172 Buckley, A. N. and Woods, R., 1995. Identifying chemisorption in the interaction of thiol collectors with sulphide minerals by XPS adsorption of xanthate on silver and silver sulphide. Colloids and Surfaces A Physicochemical and Engineering Aspects, 104,2 - 3 Buckley, A. N. and Woods, R., 1996. Relaxation of the lead-deficient sulphide surface layer on oxidized galena. Journal of Applied Electrochemistry, 26(9) 899 - 907 Buckley, A. N. and Woods, R., 1997. Chemisorption—the thermodynamically favored process in the interaction of thiol collectors with sulphide minerals. Inert. J. Miner. Process, 51 15-26... 

Chander, S. and Fuerstenau, D. W., 1975. Sulphide minerals with thiol collectors the chalcocite diethy dilhiophosphate system. 11th International Mineral Processing Congress, 1 583 - 603 Chander, S., Wie, J. M., Fuerstenau, D. W., 1975. On the native floatability and surface properties of naturally hydrophobic solids, hr P. Somasunfaran and R. G. Grieves(eds.), Advances in Interfacial Phenomena of Particulate/Solution/Gas Systems. AIME Symp., Ser., 150(71) 183-188... 

Halliday, A.N., Christensen, J.N., Lee, D-C., Hall, C.M., Ballentine, C.J., Rehkamper, M., Yi, W., Luo, X., and Barfod, D. (1998a) ICP multiple collector mass spectrometry and in situ high precision isotopic analysis. In Applications of Microanalytical Techniques to Understanding Mineralizing Processes, M.A. McKibben, W.C.P. Shanks, and W.I. Ridley, eds. Reviews in Economic Geology 7, Society of Economic Geologists, 37-51. 

O. Kangal, A. A. Sirkeci, and A. Guney, Flotation behaviour of huntite (Mg3Ca(C03)4) with anionic collectors. Internal. J. Mineral Processing 75(1-2) (2005). 

Mineral processing plant Mineral type Flotation plan Collector Dosage (gA) pH Concentrate grade (%) Recovery rate of Fe (%)... 

Fa, K., Nguyen, A. V., and Miller, J. D. 2006. Interaction of calcium dioleate collector colloids with calcite and fluorite surfaces as revealed by AFM force measurements and molecular dynamics simulation. Int. J. Miner. Process. 81 166. 

Rai, B., Krishnamurty, S., Sathish, R, and Pradip. 2008a. Salicylaldoxime derivatives as flotation collectors Quantum mechanics calculations (density functional theory) for the design of selective reagents. In Proceedings of Mineral Processing Technology—2008, IIME, Trivandrum, India. 

Flotation is the single most important method of mineral processing and is widely used for the concentration of metal ores, industrial minerals, and coals. Several investigations were carried out during the last century, and the flotation literature was immense, particularly on selective collectors and their interaction mechanisms on sulfide, oxide, and silicate minerals. However, it is often difficult... 

Uses Mineral processing surfactant flotation collection agent copper sulfide collector aids secondary gold recovery Use Level 5-25 g/ton Uniflot SP-8 [Huntsman]... 

Uses Mineral processing surfactant copper sulfide collectors for copper/zinc flotation operations Properties Liq. 

Uses Surfactant for mineral processing copper/zinc flotation collector Sulfinylbis (methane). See Dimethyl sulfoxide Sulfite lignin. See Lignin suKonate... 

R. Pugh and P. Stenius. Solution chemistry studies and flotation behavior of apatite, calcite and fluorite minerals with sodium oleate collector. Int. J. Miner. Process. 15, 1985, 193. 

The pH of the pulp to the flotation cells is carefliUy controlled by the addition of lime, which optimizes the action of all reagents and is used to depress pyrite. A frother, such as pine oil or a long-chain alcohol, is added to produce the froth, an important part of the flotation process. The ore minerals, coated with an oily collected layer, are hydrophobic and collect on the air bubbles the desired minerals float while the gangue sinks. Typical collectors are xanthates, dithiophosphates, or xanthate derivatives, whereas typical depressants are calcium or sodium cyanide [143-33-9] NaCN, andlime. 

On the basis of the function it performs, the flotation process can be divided into two categories (i) bulk and (ii) selective. The process is called bulk or collective flotation when it accomplishes the separation of several valuable components from the gangue minerals. In selective flotation, one valuable component is separated from several others. This selectivity could be accomplished by either using collectors selective with respect to a particular mineral or by differential flotation wherein two or more mineral concentrates are recovered consecutively from the same feed by using modifiers. 

Several reviews on ore processing by flotation are available.17-21 In addition to providing details of the chemistry of collectors they describe the use of activators and depressants. The former usually convert the surfaces of an ore particle which does not bind strongly to conventional collectors to one that does. The addition of Cu2+ ions to enhance the flotability of minerals such as sphalerite, a zinc sulfide, has been exploited for some time.4 Formation of a surface layer of CuS has been assumed to account for this, but the mechanisms and selectivities of such processes continue to be investigated.18,22,23... 

The PGM carriers in this ore include a variety of PGM minerals (sperrilite) and its alloys. The main problems identified associated with processing this ore type were (a) poor concentrate grade, (b) low rate of PGM flotation, (c) excessive chromium reporting to the PGM concentrate and (d) high collector consumption. 

Chrysocolla (CuOxSi02 Cu= 10-36%, SG — 2-2.4) is the most studied mineral of all the oxide minerals. Extensive laboratory studies have been conducted by numerous researchers [9-11]. The laboratory research work indicates that chrysocolla can be floated using the sulphidization method, as shown in Figure 19.4, or by hydroxamate collectors. However, none of these processes have been applied at an industrial scale. 

Flotation of the lead oxide minerals is a difficult problem not least because there are no known direct acting collectors. Normally, during oxide lead flotation, a sulphidization method is used with xanthate as a collector. In the majority of cases, the ore is pretreated using a desliming process, especially if the ore contains clay and Fe-hydroxides. Another method includes the preconcentration using heavy liquid. 

The quality of the water in which the cassiterite flotation takes place is also highly important. Both ions found in process water supply and those generated by the minerals present in the pulp may affect the performance of the collectors as well as the surfaces of either cassiterite or gangue minerals by either depressing or activating them. 

In the case of carbonatite ores, a beneficiation process involves preflotation followed by reactivation and flotation of pyrochlore. In the case of pegmatitic ores that contain silicates, biotite, albite and limonite, as the gangue minerals, direct flotation of pyrochlore can be achieved with a variety of different collectors. 

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