The present invention relates to a method of separating radioactive elements from a mixture, wherein the mixture is treated with at least one alkanesulfonic acid and at least one further acid, selected from the group consisting of hydrochloric acid, nitric acid, amidosulfonic acid and mixtures thereof and also the use of at least one alkanesulfonic acid and at least one further acid for separating radioactive elements from mixtures comprising these.

A method and system are provided for the creation of vertical and horizontal freeze wells, in a dome-like pattern around the ore body, as a hydraulic barrier to ensure the ISR mining solution and the mined minerals do not flow out of the ore body. A method to formulate a suitable mining solution used for ISR mining, where the lixivant does not freeze when using the freeze dome containment method and where the resulting PLS has a high concentration of dissolved minerals and thus eliminates the need for the solvent extraction/ion exchange step during processing is also described.

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 invention relates to a hydrometallurgical process which makes it possible to selectively recover at least one “heavy” rare earth metal, i.e. a rare earth metal with an atomic number at least equal to 62, that is in an acidic aqueous phase resulting from the treatment of spent or scrapped permanent magnets. It also relates to a hydrometallurgical process which makes it possible to selectively recover, on the one hand, at least one heavy rare earth metal present in an acidic aqueous phase resulting from the treatment of spent or scrapped permanent magnets and, on the other hand, at least one “light” rare earth metal, i.e. a rare earth metal with an atomic number at most equal to 61, that is also in this acidic aqueous phase. The invention has in particular an application in the recycling of rare earth metals present in spent or scrapped permanent magnets of the type Neodymium-Iron-Boron (or NdFeB) and, in particular, dysprosium, praseodymium and neodymium, and also in the recycling of samarium present in spent or scrapped permanent magnets of the type samarium-cobalt (or SmCo).

Methods and systems for separation of thorium from uranium and their decay products are provided. The method comprises combining a nuclear fuel feedstock comprising thorium and uranium with a first acid to form a first solution. The first solution is contacted an ion exchange resin that is selective for thorium or uranium. The thorium or uranium is at least partially removed from the first solution by binding the thorium or uranium to the ion exchange resin thereby forming a second solution. The second solution is combined with oxalic acid to precipitate uranium or thorium from the second solution to form a precipitate. The precipitate is separated from the second solution.

The invention relates to a beneficiation process for uranium ores comprising clay and carbonate minerals, the process comprising: performing a hydrocyclone step to obtain a hydrocyclone underflow fraction substantially comprising the uranium component; treating the hydrocyclone underflow fraction to effect a separation of carbonate and uranium minerals; and recovering the uranium-bearing minerals to produce a uranium concentrate.

The present disclosure provides a method for numerical simulation of reactive transport during CO.sub.2+O.sub.2 in-situ leaching of uranium at a sandstone-type uranium deposit. Unlike the traditional method for numerical simulation of solute transport during in-situ leaching of uranium with consideration of only convection and diffusion, the method permits establishment of a multi-field coupled reactive solute transport model to simulate the dynamic leaching process of a sandstone-type uranium deposit in Northern China. The method provided in the present disclosure includes: creating a thermodynamic database suitable for CO.sub.2+O.sub.2 leaching of a sandstone-type uranium deposit in Northern China, and with consideration of the dynamic reaction process of uranium dissolution under combined action of oxygen O.sub.2 (aq) and bicarbonate HCO.sub.3.sup.−, performing numerical simulation of reactive transport during CO.sub.2+O.sub.2 in-situ leaching of uranium using a TOUGHREACT simulation technology framework.

The disclosure relates to a beneficiation process for uranium ore comprising a hydrocyclone step that produces an underflow fraction containing uranium values for further processing and an overflow fraction containing fine particulate waste material

The invention relates to a beneficiation process for uranium ores comprising clay and carbonate minerals, the process comprising: performing a hydrocyclone step to obtain a hydrocyclone underflow fraction substantially comprising the uranium component; treating the hydrocyclone underflow fraction to effect a separation of carbonate and uranium minerals; and recovering the uranium-bearing minerals to produce a uranium concentrate.

A method and system are provided for the creation of vertical and horizontal freeze wells, in a dome-like pattern around the ore body, as a hydraulic barrier to ensure the ISR mining solution and the mined minerals do not flow out of the ore body. A method to formulate a suitable mining solution used for ISR mining, where the lixivant does not freeze when using the freeze dome containment method and where the resulting PLS has a high concentration of dissolved minerals and thus eliminates the need for the solvent extraction/ion exchange step during processing is also described.