Rare metals extraction

W. D. Jamrack, Rare Metal Extraction of Chemical Engineering Techniques, MacMillan Pergamon,... 

Methyl isobutyl ketone (MIK) is used as a solvent for vinyl, epoxy, acrylic, natural resins, nitrocellulose, paints, varnishes, lacquers, protective coatings, rare metal extraction, and dyes. In addition, it is used as a denaturant for rubbing alcohol, as a synthetic flavoring adjuvant, and as a fruit flavoring agent. 

Jl. Jamrack, W. D. Rare Metal Extraction by Chemical Engineering Techniques, Macmillan, New York, 1963, pp. 176-178. 

Pentafluoroethyl-2-fluoro-3,3-Z w(trifluoromethyl)-5-methyloxalane is used as a diluent for rare metal extractants and as a solvent for extractants 2-pentafluoro-2(2,2,2-trifluoro-l-trifluoromethylethyl)-l,3-dioxolane is known for its dielectric oil applications (86JAP(K) 183281). 

Centrifugal extractors have been employed for liquid-liquid extraction processes, some resembling columns and others having similarities to mixer-settlers. These often have a high throughput and short residence time and are therefore useful for the extraction of, for example, biochemical materials which tend to decompose quickly. They have not usually been considered economic for use in the rare metal extraction field in view of their very high cost when fabricated in stainless-steel, or other corrosion resistant materials, in the large sizes which would often be necessary. 

The process of calcination of oxides, hydrogen reduction of oxides to lower oxides, hydrofluorination and hydrochlorination of oxides, etc., can often be carried out by conventional chemical engineering methods. However, the high standards of purity usually required for rare metal extraction at least necessitate novel materials of construction. In addition, a considerable development and pioneering effort has been devoted to the improvement of these techniques, particularly applied to the intermediates in the production of uranium metal, uranium trioxide, dioxide and tetrafluoride. It is possible, therefore, that the resulting processes can be more widely employed in the rare metal extraction field in the future. 

The only electrolytic processes of any commercial importance for rare metal extraction are based upon the use of molten salt baths. Chlorides or fluorides of the rare metal are invariably electrolysed from solutions in similar but inert salts, usually of the alkali or alkaline earth metals. 

Besides published research papers, review articles and works of reference, material for a volume of this type normally arises from an author s own background and experience. In this connection, I wish to acknowledge the work of those of my colleagues and associates in the U.K. Atomic Energy Authority whose work has contributed to the design of various Authority processes which have been discussed. I also wish to thank those outside the Authority, concerned with rare metal extraction, whose factories I have had the privilege of visiting. 

SOLID POLYMERIC EXTRACTANT PROPERTIES ON METAL IONS EXTRACTION MECHANISM OF RARE METALS EXTRACTION... 

Y. Knzovov, V. Korovin, V. Savel eva, and A. Komarov. 31P, 45Sc NMR Comparison of mechanisms of rare metals extraction by solvent extractants and ones introduced in TVEX porous matrix, Proc. ISEC 88, 3, 159—162 (1988). 

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