Uses of cyclic amine monoamides for extracting uranium(VI) and/or plutonium(IV) from an acidic aqueous solution, as well as for totally or partially separating uranium(VI) from plutonium(IV) from an acidic aqueous solution. A method for treating an aqueous solution resulting from the dissolution of spent nuclear fuel in nitric acid to extract, separate and decontaminate uranium(VI) and plutonium(IV) in a single cycle and without resorting to any operation of reducing plutonium(IV), and wherein a cyclic amine monoamide or a mixture of cyclic amine monoamides is used as extractant. The cyclic amine monoamides have formula (I):

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Methods for forming particulates that are highly consistent with regard to shape, size, and content are described. Particulates are suitable for use as reference materials. Methods can incorporate actinides and/or lanthanides, e.g., uranium, and can be used for forming certified reference materials for use in the nuclear industry. Methods include formation of an aerosol from an oxalate salt solution, in-line diagnostics, and collection of particles of the aerosol either in a liquid impinger or on a solid surface.

The present disclosure relates to a process and system for recovery of one or more metal values using solution extraction techniques and to a system for metal value recovery. In an exemplary embodiment, the solution extraction system comprises a first solution extraction circuit and a second solution extraction circuit. A first metal-bearing solution is provided to the first and second circuit, and a second metal-bearing solution is provided to the first circuit. The first circuit produces a first rich electrolyte solution, which can be forwarded to primary metal value recovery, and a low-grade raffinate, which is forwarded to secondary metal value recovery. The second circuit produces a second rich electrolyte solution, which is also forwarded to primary metal value recovery. The first and second solution extraction circuits have independent organic phases and each circuit can operate independently of the other circuit.

In alternative embodiments, the invention provides processes and methods for the recovery, removal or extracting of, and subsequent purification of uranium from a wet-process phosphoric acid using a continuous ion exchange processing approach, where the uranium is recovered from a phosphoric acid, or a phos-acid feedstock using either a dual or a single stage extraction methodology. In both cases an intermediate ammonium uranyl-tricarbonate solution is formed. In alternative embodiments, in the dual cycle approach, this solution is contacted in a second continuous ion exchange system with a strong anion exchange resin then subsequently recovered as an acidic uranyl solution that is further treated to produce an intermediate uranyl peroxide compound which is ultimately calcined to produce the final uranium oxide product. In alternative embodiments, in the single cycle case, the intermediate ammonium uranyl-tricarbonate solution is evaporated to decompose the ammonium carbonate and produce an intermediate uranium carbonate/oxide solid material. These solids are digested in an acid medium, and then processed in the same manner as the secondary regeneration solution from the dual cycle process to produce an intermediate uranyl peroxide that is calcined to produce a final uranium oxide product.

The present invention describes a method for purification of .sup.225Ac from irradiated .sup.226Ra-targets provided on a support comprising a leaching treatment of the .sup.225Ra-targets for leaching essentially for the entirety of .sup.223Ac and .sup.226Ra with nitric or hydrochloric acid, followed by a first extraction chromatography for separating .sup.225Ac from .sup.226Ra and other Ra-isotops and a second extraction chromotography for separating .sup.225Ac from .sup.210Po and .sup.210Pb. The finally purified .sup.225Ac can be used to prepare compositions useful for pharmaceutical purposes.

A method for recovering thorium and rare earth elements from rare earth waste residues comprises: (1) mixing rare earth waste residues with an inorganic acid and heating to obtain a stock solution containing thorium and rare earth elements; (2) extracting thorium and rare earth elements from the stock solution with an organic phase containing an extractant; (3) washing the organic phase obtained after extraction in step (2) with a washing solution to move rare earth elements into the aqueous phase and remain thorium in the organic phase; (4) back-extracting the organic phase containing thorium obtained in step (3) with a back-extraction solution to move thorium in the organic phase into the aqueous phase; said extractants are alkyl phosphonic acid monoalkyl ester and dialkylphosphinic acid.

In alternative embodiments, the invention provides processes and methods for the recovery, removal or extracting of, and subsequent purification of uranium from a wet-process phosphoric acid using a continuous ion exchange processing approach, where the uranium is recovered from a phosphoric acid, or a phos-acid feedstock using either a dual or a single stage extraction methodology. In both cases an intermediate ammonium uranyl-tricarbonate solution is formed. In alternative embodiments, in the dual cycle approach, this solution is contacted in a second continuous ion exchange system with a strong anion exchange resin then subsequently recovered as an acidic uranyl solution that is further treated to produce an intermediate uranyl peroxide compound which is ultimately calcined to produce the final uranium oxide product. In alternative embodiments, in the single cycle case, the intermediate ammonium uranyl-tricarbonate solution is evaporated to decompose the ammonium carbonate and produce an intermediate uranium carbonate/oxide solid material. These solids are digested in an acid medium, and then processed in the same manner as the secondary regeneration solution from the dual cycle process to produce an intermediate uranyl peroxide that is calcined to produce a final uranium oxide product.

The disclosure relates to a beneficiation process for low grade uranium ore, wherein the process comprises a primary beneficiation stage comprising: wet scrubbing the low grade uranium ore to separate the low grade ore into a fine fraction and a coarse fraction; screening the fine fraction according to a size separation parameter to provide an undersize fraction and an oversize fraction, wherein the uranium predominantly reports to the undersize fraction; and separating the undersize fraction to produce an intermediate uranium concentrate. The intermediate uranium concentrate may be further processed in a secondary beneficiation stage to produce a high grade uranium concentrate.

A process for extracting uranium from an acidic uranium, chloride, iron and sulphate containing solution, including the steps: a. contacting the solution with an organic phase containing a trialkylphosphine oxide to form a uranium loaded organic phase; b. scrubbing the uranium loaded organic phase to remove any impurities and form a scrubbed organic phase; c. stripping the scrubbed organic phase with an acidic sulphate solution to produce an aqueous uranium strip solution; and precipitating a uranium product from the aqueous uranium strip solution.

The invention pertains to a process for separating at least one first chemical element E.sub.1 from at least one second chemical element E.sub.2 coexisting in a mixture in the form of oxides, comprising the following steps: a) a step to solubilise a powder of one or more oxides of the said at least one first chemical element E.sub.1 and a powder of one or more oxides of the said at least one second chemical element E.sub.2 in a medium comprising at least one molten salt of formula MFAlF.sub.3 wherein M is an alkaline element, after which there results after this step a mixture comprising the said molten salt, a fluoride of the said at least one first chemical elements E.sub.1 and a fluoride of the said at least one second chemical element E.sub.2; b) a step to contact the mixture resulting from step a) with a medium comprising a metal in the liquid state, the said metal being a reducing agent capable of predominantly reducing the said at least one first chemical element E.sub.1 relative to the said at least one second chemical element E.sub.2, after which there results after this step a two-phase medium comprising a first phase called metal phase comprising the said at least one first chemical element E.sub.1 in oxidation state 0, and a second phase called saline phase comprising the molten salt of above-mentioned formula MFAlF.sub.3 and a fluoride of the said at least one second chemical element E.sub.2.