Cobalt extraction

Cai Z., Liu Z. Studies on oxidation states of cobalt extracted from soil with EDTA+HOAc+NTLtOAc. Pedosphere 1991 1 109. 

Simons, C. S. Materials selection and design problems in a nickel-cobalt extraction plant. Corrosion 15, Tech. Topics 1959, 95-98. 

Cobalt difluoride, 7 231-232 Cobalt dilanthanum tetroxide, uses, 7 24 It Cobalt driers, 9 147-148 CobaltCII) ethylhexanoate, 7 230 Cobalt extraction, 10 791 Cobalt fluoroborate hexahydrate, 4 157t, 158, 159... 

Sulfuric acid leach liquors, nickel and cobalt extraction from, 70 791 Sulfuric acid lithium recovery process, 75 125-126... 

Standing Committee of Analysts (DoE) (1979) The Analysis of Agricultural Materials -Cobalt, Extractable in SoilMethod22, MAFF Technical Bulletin RB 427, HMSO, London, UK. 

A standard official method has been published for the determination of cobalt in plant material [8 ]. The samples are digested with 1 4 v/v perchloric acidmitric acid and the residue dissolved in nitric acid. Cobalt is then extracted into chloroform as the diethyldithiocarbonate. The latter complex is decomposed by bromine and cobalt extracted into dilute hydrochloric acid. Following the addition of a borate buffer, cobalt is then extracted as the o-nitrocresol complex [9]. Excess coupling agent is removed by repeated extraction with copper acetate solution and cobalt determined spectrophotometrically at 360 nm. See Sects. 7.34.1, 7.34.3 and 7.34.4. 

Ribeiro CP, Costa AOS, Lopes IPB, Campos FF, Ferreira AA, and Salum A. Cobalt extraction and cobalt-nickel separation from a simulated industrial leaching liquor by liquid surfactant membranes using Cyanex 302 as carrier. J Membr Sci 2004 241 45-54. Frankenfeld JW, Cahn RP, and Li NN. Extraction of copper by liquid membranes. Sep Sci Technol 1981 16 385 102. 

It is generally less effective for leaching limonite ore and sulphur dioxide injection may be needed to achieve high cobalt extraction. 

Limonite ore is leached with sulfuric acid at around 250 C. At this temperature, acid consumption is minimised because iron is hydrolysed to hematite, kinetics are rapid and nickel and cobalt extractions typically exceed 95%. 

Nickel extraction is improved by increased temperature, ammonia concentration and ferrous sulphate concentration cobalt extraction requires low temperature and ferrous sulphate concentration as well as high ammonia concentration. High ferrous sulphates to ore ratios do not improve nickel extraction, likely due to magnetite precipitation around goethite particles, thus preventing contact between particle and reductant. 

Commercially Used SX Reagents for Nickel and Cobalt Extraction... 

It is showed in Figure 3 that when the mass of the resin is 2g and the pH value is smaller than 4.5, the cobalt extractive content increased with the increase of pH value. When the pH value of the solution is larger than 4.5, the cobalt extractive content is trends to become stable. At this moment, both the cobalt distribution ratio and the extraction rate get the best results. However, when the pH value is too high, the extracted residual liquid is easy to emerge precipitation. Therefore, the pH value of the initial solution should be controlled at 4.6 4.8. 

Experiments 1-4 show increasing nickel and cobalt extraction with increasing acid addition over the range of 100-1000 kg/t of tailings. Clearly addition of acid to ever higher levels produces only an incremental benefit in overall metal extraction. At 10 X the acid addition (1000 kg/t versus 100 kg/t) the nickel extraction doubles and the cobalt extraction is only about 50% higher. The iron extraction rises from 5% to 89% over the same range of acid addition. The terminal pH and calculated acid consumptions (for dissolved species) indicates that most of the acid was... 

Ammonia Some refrigeration units, plan printers, nickel/cobalt extraction... 

Nickel-cobalt extraction - 201 Nickel compounds - 622 Nickel electrolyte - 201... 

P-diketones Hostarex DK16 LDC54 X151 proposed for copper extraction from ammoniacal solution copper extraction from ammoniacal solution proposed for cobalt extraction from ammoiuacal solution... 

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