The use of carbamides as extractants for fully or partially separating uranium(VI) from plutonium(IV) in an aqueous solution obtained by dissolving a spent nuclear fuel in nitric acid, by method of liquid-liquid extraction, without carrying out any reduction of the plutonium(IV) to plutonium(III). The invention also relates to new carbamides. Uses are the processing of spent nuclear fuels based on uranium (especially uranium oxides—UOX) or uranium and plutonium (especially mixed uranium and plutonium oxides—MOX).

A method for recovering metals from waste materials includes steps of contacting a waste material feed stream with a first lixiviant adapted to leach copper and other base metals from the waste material feed stream and provide a treated waste material feed stream, recovering copper metal from the first lixiviant, contacting the treated waste material stream with a second lixiviant adapted to leach noble metals from the treated waste material feed stream and recovering gold from the second lixiviant.

Provided is a method for treating an alloy by which nickel and/or cobalt can be selectively isolated from an alloy that contains copper as well as nickel and/or cobalt, in a waste lithium ion battery. The present invention is a method for treating an alloy, by which a solution that contains nickel and/or cobalt is obtained from an alloy that contains copper as well as nickel and/or cobalt, the method including: a leaching step in which a leachate is obtained by subjecting an alloy to an acid-based leaching treatment under conditions in which a sulfurizing agent is also present; a reduction step in which a reduced solution is obtained by subjecting the leachate to a reduction treatment using a reducing agent; and an oxidation/neutralization step in which a solution that contains nickel and/or cobalt is obtained by adding an oxidizing agent and also a neutralizing agent to the reduced solution.

Method for recovering Cr from a pickling bath of an aqueous solution containing sulphate and Cr from a pickled metal, the method including: -forming an aqueous two-phase system from a portion of the pickling bath and a polymer including an unhindered ether function, the proportion of polymer in the ternary mixture including the pickling bath, considered to be a unique chemical component, water and polymer, ranging between the line of the equation «weight % of polymer=100%−weight % of pickling bath» and the binodal curve of the pickling bath/polymer mixture, the two-phase aqueous system including polymer and non-polymer phases;—separating the respective phases;—allowing precipitates containing Cr to form in the polymer phase;—carrying out solid/liquid separation of the polymer phase to separate the polymer and the precipitates containing Cr;—and processing the precipitates to recover the Cr. A facility is also disclosed.

A process for recovering copper from heap leach residues containing residual copper, includes identifying a production zone within the heap leach residues for secondary leaching, drilling wells into the heap at locations suitable for delivering leach solution into the production zone, injecting the leach solution including ferric ions through the wells and aerating the production zone to facilitate oxidative reactions within the production zone, and collecting effluent from the heap for copper recovery therefrom.

A process for recovering copper from heap leach residues containing residual copper, includes identifying a production zone within the heap leach residues for secondary leaching, drilling wells into the heap at locations suitable for delivering leach solution into the production zone, injecting the leach solution including ferric ions through the wells and aerating the production zone to facilitate oxidative reactions within the production zone, and collecting effluent from the heap for copper recovery therefrom.

A method for extracting rare earth elements (REEs) from a REE hyperaccumulator, including: subjecting the REE hyperaccumulator to microwave-assisted digestion to obtain a REE extract; subjecting the REE extract to absorption with a chelating resin and elution to obtain a purified REE solution; and subjecting the purified REE solution to precipitation and calcination to obtain high-purity rare earth compound.

The present disclosure relates to a metal recovery process comprising a solvent extraction process. In an exemplary embodiment, the solution extraction system comprises a plant with a first and second circuit. A high-grade pregnant leach solution (“HGPLS”) is provided to the first and second circuit, and a low-grade pregnant leach solution (“LGPLS”) is provided to the second circuit. The first circuit produces a rich electrolyte, which can be forwarded to a primary metal recovery, and a low-grade raffinate, which can be forwarded to a secondary metal recovery process. The second circuit produces a rich electrolyte, which can also be forwarded to the primary metal recovery process. The first and second circuits are in fluid communication with each other.

The present disclosure relates to a metal recovery process comprising a solvent extraction process. In an exemplary embodiment, the solution extraction system comprises a plant with a first and second circuit. A high-grade pregnant leach solution (“HGPLS”) is provided to the first and second circuit, and a low-grade pregnant leach solution (“LGPLS”) is provided to the second circuit. The first circuit produces a rich electrolyte, which can be forwarded to a primary metal recovery, and a low-grade raffinate, which can be forwarded to a secondary metal recovery process. The second circuit produces a rich electrolyte, which can also be forwarded to the primary metal recovery process. The first and second circuits are in fluid communication with each other.

A mixing arrangement for mixing two solutions, a mixer settler unit and a use. The mixing arrangement includes a mixing device arranged in the mixing space for rotating therein, the mixing device comprising at least two helical bars supported around a shaft and rising upwards from the bottom section of the mixing space. The helical bars are fixed to the shaft with support spokes. The ratio of the diameter (D) of the mixing device to the average diameter (T) of the mixing space, that is D/T, is 0.47 at most.