Processing schemes for the extraction and/or separation of rare earth elements (REEs) from rare earth containing products such as rare earth mineral ore bodies and intermediate products derived from rare earth mineral ore bodies. The processing schemes may be applied independently or in various combinations to produce end-products that have a very high purity with respect to REEs, including high value critical REEs. The processes may include acid digestion, formation of rare earth oxalate compounds, metathesizing of rare earth oxalate compounds, selective precipitation and/or solvent extraction to form the high purity REE end products.

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.

A method for recovering one or more of copper, uranium and a precious metal from an ore material, including: (a) forming a heap of the ore material; (b) during active heap irrigation, contacting the heap of the ore material with an iron containing acidic leach liquor having a high chloride content in the presence of an oxygen containing gas, and producing a pregnant leach solution; and (c) recovering one or more of copper, uranium and a precious metal from the pregnant leach solution.

Provided herein are processes for recovering metal present at low concentration from an acidic aqueous solution, including contacting the acidic aqueous solution with an organic phase solution including one or more 5-(C.sub.8 to C.sub.14 alkyl)-2-hydroxyaryloxime, thereby extracting at least part of the metal from the acidic aqueous phase; increasing or maintaining the concentration of metal in the organic phase solution by recycling a portion of the organic phase solution containing the metal and contacting the organic phase with an acidic aqueous solution containing the metal; contacting the organic phase solution containing metal with an aqueous phase strip solution comprising an inorganic compound that back-extracts the metal, thereby stripping at least part of the metal from the organic phase solution to the aqueous phase strip solution; and separating the metal from the aqueous phase strip solution, thereby recovering the metal.

The present invention provides a process for the production of a uranium trioxide yellowcake from a uranium peroxide precipitate, the peroxide precipitate being in the form of a low solids content, uranium rich feed slurry, the process including the stages of: a. thickening the feed slurry to produce a thickener underflow with a solids content in the range of 15 to 50% w/w and a thickener overflow; b. dewatering the thickener underflow to produce a solids cake with a solids content of at least 50% w/w and a dewater overflow; and c. calcining the solids cake at a temperature in the range of 450° C. to 480° C. to produce a calcined uranium trioxide yellowcake.

The present invention describes a process for removing uranium from a copper concentrate by magnetic separation (low and high field) to reduce the uranium content to commercially acceptable levels.

Siderocalin-metal chelator combinations that bind metallic radioisotopes used in nuclear medicine with high affinity are described. The high affinity siderocalin-metal chelator combinations include a number of chelator backbone arrangements with functional groups that coordinate with metals. The siderocalin-metal chelator combinations can be used to deliver radionuclides for imaging and therapeutic purposes.

Siderocalin-metal chelator combinations that bind metallic radioisotopes used in nuclear medicine with high affinity are described. The high affinity siderocalin-metal chelator combinations include a number of chelator backbone arrangements with functional groups that coordinate with metals. The siderocalin-metal chelator combinations can be used to deliver radionuclides for imaging and therapeutic purposes.

A fiber useful in the absorption of metal ions from aqueous solutions, the fiber comprising a polyolefin backbone having a diameter of at least 1 micron and having covalently appended on its surface halogen atoms and vinyl-addition polymeric grafts functionalized with metal-binding groups, such as at least one functional group selected from carboxylate, keto, aldo, amino, imino, nitrile, amido, oxime, amidoxime, imide dioxime, and hydroxamate groups. The vinyl-addition polymeric grafts may also be further functionalized with hydrophilic groups different from the metal-binding groups, wherein the hydrophilic groups may be selected from carboxylate, sulfone, sulfonate, phosphonate, alkylammonium, iminium, amide, pyrrolidone, and polyalkyleneglycol groups. Also described are methods for producing the functionalized fibers, and methods for using the functionalized fiber, particularly in extracting metal ions from metal-containing solutions.

The present invention relates to use of an amino-containing neutral phosphine extractant of Formula I in extraction and separation of thorium, and a process of extracting and separating thorium using the amino-containing neutral phosphine extractant of Formula I,

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wherein, R.sub.1 and R.sub.2 are each independently selected from the group consisting of C.sub.1-C.sub.12 alkyl, R.sub.3 and R.sub.4 are each independently selected from the group consisting of C.sub.1-16 alkyl and hydrogen, and n is an integer of 1 to 8.