Hydrometallurgical applications

Sources of thermodynamic data which the authors have found to be valuable in hydrometallurgical applications have been assembled in Table II. 

Solvent extraction is now a proven technology for the commercial extraction, separation, and concentration of a wide range of metals both from primary and secondary sources (see Chapter 14). In recent years, there has been a reduction in the development, production, and marketing of new commercial extractants as the overall costs of such activities increases. However, the use of established reagents in new hydrometallurgical applications continues to expand. 

The Kuhni contactor (Fig. 13e) has gained considerable commercial application in Europe. Its principal features are the use of a shrouded turbine impeller to promote radial discharge within the compartments and a variable hole arrangement to allow flexibility of design for different process applications. Kuhni extractors are used for extraction of petrochemicals and chemicals, phosphoric acid purification, as well as hydrometallurgical applications and wastewater treatment. Columns up to 16.5 ft in diameter have been constructed. 

The term mechanical activation should only be used for processes where a solid is pretreated prior to a subsequent reaction. The mechanical activation of solids is often used on an industrial scale to effect the calcination times of ceramics, or the solubility of ores. For a review of hydrometallurgical applications, see Ref. [38],... 

Metal ions separation for hydrometallurgical applications has attracted considerable interest. Selective separations of alkali, alkali earth, heavy metal ions, rare earth, precious metals, etc. are studied by many authors using all the above-described techniques. Referenced works in metal separations classified according to the OHLM techniques with types of membrane walls and carriers used are listed in Table 13.6. 

FIG. 15-4 Example process scheme used in hydrometallurgical applications. [Taken from Cox, Chap. 1 in Science and Practice of Liquid-Liquid Extraction, vol 2, Thornton, ed. (Oxford, 1992), with permission. Copyright 1992 Oxford University Press.]... 

TABLE 8.2-2 Hydrometallurgical Applications of Souse Common Solvating Extractants... 

TABLE 8.2-3 Hydrometallurgical Applications of Some Cxmmion Cation-Exchanging Extractants... 

Hydrometallurgical Applications of Solid Extractants (TVEX) of Rare... 

Application of solid extractants on hydrometallurgical applications has the benefits of increasing extraction capacity and reducing labor expenses and improving the working conditions of personnel at the expense of elimination of highly filtrated pulps operation. Exclusion of flammable solvents from production process allows for a decrease in the associated fire hazard. Moreover, tri-butyl-phosphate consumption decreases significantly by reduction of losses with nonseparated emulsions. 

Development of Solvent-Impregnated Resins for Gold Hydrometallurgical Applications.319... 

DEVELOPMENT OF SOLVENT-IMPREGNATED RESINS FOR GOLD HYDROMETALLURGICAL APPLICATIONS... 

A. Warshawsky, Solvent impregnated resins in hydrometallurgical applications, Inst. Min. Metal. (London) Trans. Sect. C, 83, (1974), 101. 

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