Solvent leaching

Solvent extraction and leaching Solvent extraction (liquid-liquid extraction)... 

The application of solvent extraction to copper recovery has been a major growth area since the last review of this series.11,13 Almost 30% of world production in 2000 involved the use of sulfuric acid heap leaching, solvent extraction, and electrowinning, far exceeding earlier predictions.136... 

Figure 5 A simplified flowsheet and materials balance for the recovery of copper from oxidic and transition ores by heap leaching, solvent extraction and electrowinning.

Cymet (1) [Cyprus Metallurgical] A process for extracting copper from sulfide ores. It involves leaching, solvent extraction, and electrowinning. Developed by the Cyprus Metallurgical Processes Corporation, Golden, CO. Superseded by Cymet (2). 

Kordosky, G. A. (2002) Copper recovery using leach/solvent extraction/electrowinning technology forty years of innovation, 2.2 million tonnes of copper annually, in International Solvent Extraction Conference, Cape Town, South Africa, Mar. 17-21, 2002. 

IB) ACID LEACH. ION EXCHANGE AND ACID LEACH.SOLVENT EXTRACTION PROCESSES... 

Fig. 21.12. Uranium ore mill processes (A) carbonate leach, caustic precipitation process (B) acid leach, ion exchange and acid leach, solvent extraction processes (C) acid leach, resin-in-pulp process.

BioNIC [Biological NICkel] A biological process for leaching nickel from its ores. It comprises bacterial leaching, solvent extraction, and electrowinning. Developed by BHP Billiton at Yabulu from 1999, but not commercialized by 2004 because no ore body of a suitable concentration and size had been identified. 

Biocides function by becoming active on the surface of the material to destroy the fungi. Plasticiser transfer to the surface is limited by the process of diffusion of the plasticiser within the material, the fungus also acting as a leaching solvent (370). Addition levels of the active ingredient are in the 400-2000 ppm level and the active biocide is normally supplied dispersed in a plasticiser or ESBO carrier. 

The extraction cells used in DPHSE include those typically employed in SFE [109,151], empty HPLC columns [149] and specially designed stainless steel chambers [57,75,148]. The use of an SFE chamber as extraction cell is not recommended because the polyimide seals in it can fail at high temperatures [6]. On the other hand, the problem with empty HPLC columns is that they usually have small diameters and hence low volumes — this can result in excessive pressure build-up and bursting of the column. As a rule, DPHSE extraction cells consist of a stainless steel cylinder closed with screws at either end that permit the circulation of the leaching solvent through them. The screw caps also contain stainless steel filter plates to ensure that the sample remains in the extraction chamber. 

Since the mid-1960s, solvent extraction has been applied on a commercial scale to the recovery of copper from aqueous solutions obtained from the leaching of acid-soluble copper ores with dilute sulfuric acid. At present, several plants producing up to 200 t of copper per day by an integrated leach—solvent extraction—electrowinning route are in operation throughout the world. 

Fig. 18 General flowsheet of copper leaching, solvent extraction, and electrowinning process. 

Processes that use chloride leaching, solvent extraction to sulfate solution, and electrowinning from sulfate solution. 

Cobalt is produced as a coproduct of nickel or copper refining. Copper-cobalt sulfide concentrates can be processed by the RLE process. Mixed cobalt-nickel sulfides can be precipitated from ammoniacal leach solutions and as mixed nickel-cobalt hydroxide or carbonate from acid sulfate leach processes. From chloride leach solutions, cobalt can be separated by solvent extraction. Most cobalt production is associated with nickel production from sulfide and laterite ores. Pressure leaching, solvent extraction followed by the electrowinning of... 

L. Liang, M. Horvat, X.B. Feng et al.. Reevaluation of Distillation and Comparison with FINO3 Leaching/Solvent Extraction for Isolation of Methylmercury Compounds from Sediment/Soil Samples, Appl. Organo-metal. Chem. 18(6), 264-270, June (2004). 

Compared to conventional antioxidants, reactive antioxidants that are capable of becoming covalently bound to the polymer backbone are not readily lost from polymers during fabrication and in-service. There is a lot of evidence that demonstrates the performance (in terms of polymer protection) of immobilized antioxidants in practice, especially when polymer products are subjected to harsh environment, e.g., exposure to high temperatures, UV-light and leaching solvents. It is clear from this that high mobility of low molar mass antioxidants is not a necessary prerequisite to achieving stabilization and attachment of antioxidants to polymers can be industrially beneficial. 

As an example of the acid-leaching, solvent extraction class of uranium-concentration processes, a description will be given of the process used in the large uranium mill of the Kerr-McGee Corporation at Grants, New Mexico. This has been condensed from a 1960 paper by Hazen... 

Oust Collection by Disposition of Dust Electrostatic Precipitator (Lurgi) Recycled to Zinc Plant Bag House Recycled to Sinter Machine Bag House Leaching / Solvent Extraction tor Zn Cd Recovery Bag Housa Recycled to Sinter Machine ESP (Lurgi) Recirculated to QSL-Converter... 

The British company Reunion Mining Pic (RM) performed a techno-economical feasibility study for the Skorpion mine (Namibia) during 1S 7 and 1998. At that time, RM entered in contact with the R D Division of Tunicas Reunidas S.A. (TR). The objective was to apply the modified ZINCEX process (MZP) to the treatment of Skorpion ore to produce SHG zinc. One of the most important stages of the feasibility study was the piloting of key sections of the process namely, leaching, solvent extraction and electrowinning. 

Koyama and Tanaka examined the oxidative roasting—selective leaching—solvent extraction process of the scrap neodymium magnet (Koyama and Tanaka, 2009, 2011a Koyama et al., 2009 Tanaka et al., 2009). When 1000 kg of scrap magnet (Nd2Fci4B) is dissolved by mineral acid, its required amount is calculated on the basis of the following reactions ... 

The rate of leaching depends on the nature of the solvent as well as the plasticiser structure. Different rank orders for candidate plasticisers are observed, depending on whether the leaching solvent is ordinary water, soapy water or mineral oil. 

Solvent extraction and electrowinning (SX-EW) is a hydrometallurgical process involving three fundamental steps ore leaching, solvent extraction, and electrowinning. The first step consists of leaching the copper ore with a weak acidic solution, which, typically, is sulfuric acid. 

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