Metal phase partitioning, molten

Americium is separated from plutonium by a liquid-liquid extraction process involving immiscible molten salt and molten plutonium metal phases. The molten salt extraction process is based upon equilibrium partitioning (by oxidation-reduction reactions) of americium and plutonium between the molten chloride salt and molten plutonium metal phases. 

Salt Transport Processing (8, 9, 10, 11) The selective transfer of spent fuel constitutents between liquid metals and/or molten salts is being studied for both thorium-uranium and uranium-plutonium oxide and metal fuels. The chemical basis for the separation is the selective partitioning of actinide and fission-product elements between molten salt and liquid alloy phases as determined by the values of the standard free energy of formation of the chlorides of actinide elements and the fission products. Elements to be partitioned are dissolved in one alloy (the donor... 

Other variables that affect the partitioning of solutes between molten salt and liquid metal phases include temperature,... 

Matte-slag-gas reactions in Cu-Fe-Ni sulphide ores. Sulphide ores are a major source of Cu, Ni and precious metals. A basic principle of the extraction processes is to blow air into the molten sulphide in order to oxidise (1) S, which forms a gas and (2) Fe, which forms predominantly FeO and then partitions to a slag phase which covers the matte. A key element in the recovery of the metals is the solidification of the matte which separates into a sulphur-rich matte and metal-rich liquid. This process may occur under non-equilibrium conditions with precious metals concentrating in the last metallic liquid. 

Differentiation of terrestrial planets includes separation of a metallic core and possible later fractionation of mineral phases within either a solid or molten mantle (Figure 1). Lithophile and siderophile elements can be used to understand these two different physical processes, and ascertain whether they operated in the early Earth. The distribution of elements in planets can be understood by measuring the partition coefficient, D (ratio of concentrations of an element in different phases (minerals, metals, or melts)). 

The pyrometallurgical methods were developed based on the differences between zirconium and hafnium in oxidation and reduction characteristics [11, 12] volatility [13-16] electrochemical properties [17-19] and molten metal-molten salt equilibrium [20, 21], The extractive distillation process, using carbochlori-nation of zircon [13], is in operation by CEZUS in France. Both chlorides are sublimated and run through a vertical distillation column containing molten aluminium chloride and potassium chloride. Both hafnium and zirconium tetrachloride chlorides dissolve, but hafnium tetrachloride has a higher vapour pressure and is therefore condensed from the top of the column in a hafnium-enriched mixture. The zirconium tetrachloride is partitioned to a liquid phase and recovered from a salt, typically containing less than 50 ppm hafnium. 

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