A method for recycling copper-indium-gallium-selenium (CIGS) waste is provided, comprising: vacuum distilling the CIGS waste to separate out selenium and obtain a distillation residue; electrolyzing the distillation residue to obtain copper and a remaining electrolyte containing indium and gallium; and separating indium and gallium from the remaining electrolyte containing indium and gallium. The method provides a novel route for recycling CIGS waste, the process is simple, and the environmental pollution caused by CIGS waste is decreased. Further, the residual raffinate can be reused in electrolyzing of the distillation residue as a copper sulfate electrolyte by adding appropriate amount of copper sulfate and sulfuric acid therein, such that the circulation of the copper sulfate electrolyte forms a closed cycle and the discharge of wastewater and pollution to the environment are reduced.

Provided is a method for processing lithium ion battery waste, which can effectively precipitate aluminum ions and iron ions in the solution by neutralization and relatively easily separate the precipitate. The method for processing lithium ion battery waste includes: a leaching step of leaching battery powder in an acid, the battery powder containing at least aluminum and iron and being obtained from lithium ion battery waste, and removing a leached residue by solid-liquid separation to obtain a leached solution containing at least aluminum ions and iron ions; and a neutralization step of adding phosphoric acid and/or a phosphate salt and an oxidizing agent to the leached solution, increasing a pH of the leached solution to a range of 2.0 to 3.5, precipitating the aluminum ions and the iron ions in the leached solution as aluminum phosphate and iron phosphate, respectively, and removing a neutralized residue by solid-liquid separation to obtain a neutralized solution.

Provided is a method for processing lithium ion battery waste, which can effectively precipitate aluminum ions and iron ions in the solution by neutralization and relatively easily separate the precipitate. The method for processing lithium ion battery waste includes: a leaching step of leaching battery powder in an acid, the battery powder containing at least aluminum and iron and being obtained from lithium ion battery waste, and removing a leached residue by solid-liquid separation to obtain a leached solution containing at least aluminum ions and iron ions; and a neutralization step of adding phosphoric acid and/or a phosphate salt and an oxidizing agent to the leached solution, increasing a pH of the leached solution to a range of 2.0 to 3.5, precipitating the aluminum ions and the iron ions in the leached solution as aluminum phosphate and iron phosphate, respectively, and removing a neutralized residue by solid-liquid separation to obtain a neutralized solution.

Disclosed herein is a method for extracting precious metals from supported catalysts. The precious metal in one embodiment is rhodium. The supported catalyst may be from equipment, such as a used catalytic converter. The method is carried out at low temperature, and does not require harsh conditions, such as the use of a strong acid. The method involves contacting the catalytic material with a polar molecule and a reactive gas.

The present invention relates to a method for the recovery of palladium from an aqueous solution, comprising the steps of: (A) providing a dispersion comprising an aqueous dispersing phase comprising palladium(II), at least one non-ionic surfactant and at least one compound bearing a beta-dithiocarbonyl group, so as to form a hydrophobic complex of palladium(II) with the compound bearing a beta-dithiocarbonyl group; (B) heating the dispersion resulting from step (A) to a temperature at least equal to its cloud point so as to obtain the phase separation between the aqueous dispersing phase and a dispersed phase rich in surfactant comprising at least a part of said hydrophobic complex; (C) separating the dispersed phase rich in surfactant from the aqueous dispersing phase resulting from step (B); and (D) recovering the hydrophobic complex of palladium(II) with the compound bearing a beta-dithiocarbonyl group.

Novel dissymmetric N,N-dialkylamides which meet the following formula (I): ##STR00001##
where R represents a linear or branched alkyl group at C.sub.8 to C.sub.15. A method for synthesizing these N,N-dialkylamides, and to the uses of same as extractants, alone or in admixture, in order to extract uranium and/or plutonium from an aqueous acid solution, or to totally or separate uranium from plutonium from an aqueous acid solution and, in particular, an aqueous solution resulting from dissolving spent nuclear fuel in nitric acid. Further, a method for processing an aqueous solution resulting from the dissolution of a spent nuclear fuel in nitric acid, allowing the uranium and plutonium contained in the solution to be extracted, separated and decontaminated in a single cycle, without requiring any plutonium reduction operation, and in which one of the aforementioned N,N-dialkylamides or a mixture of same is used as extractant. Applications for the method include the processing of spent nuclear fuels, in particular comprising uranium (e.g. UOX) or uranium and plutonium (e.g. MOX).

Novel dissymmetric N,N-dialkylamides which meet the following formula (I): ##STR00001##
where R represents a linear or branched alkyl group at C.sub.8 to C.sub.15. A method for synthesizing these N,N-dialkylamides, and to the uses of same as extractants, alone or in admixture, in order to extract uranium and/or plutonium from an aqueous acid solution, or to totally or separate uranium from plutonium from an aqueous acid solution and, in particular, an aqueous solution resulting from dissolving spent nuclear fuel in nitric acid. Further, a method for processing an aqueous solution resulting from the dissolution of a spent nuclear fuel in nitric acid, allowing the uranium and plutonium contained in the solution to be extracted, separated and decontaminated in a single cycle, without requiring any plutonium reduction operation, and in which one of the aforementioned N,N-dialkylamides or a mixture of same is used as extractant. Applications for the method include the processing of spent nuclear fuels, in particular comprising uranium (e.g. UOX) or uranium and plutonium (e.g. MOX).

The present invention provides a method for easy and efficient recovery of high purity scandium from nickel oxide ore, the method comprising: an adsorption step for passing a scandium-containing solution through an ion exchange resin to adsorb scandium on the ion exchange resin; an elution step for eluting scandium from the ion exchange resin to obtain a post-elution solution; an impurity extraction step in which after the elution step, the scandium-containing solution is subjected to a first solvent extraction using an amine-based impurity extractant and is separated into a first aqueous phase containing scandium and into a first organic phase containing impurities; and a scandium extraction step in which the first aqueous phase is subjected to a second solvent extraction using an amide derivative-containing scandium extractant to obtain a second organic phase containing scandium.

The present invention provides a method for easy and efficient recovery of high purity scandium from nickel oxide ore, the method comprising: an adsorption step for passing a scandium-containing solution through an ion exchange resin to adsorb scandium on the ion exchange resin; an elution step for eluting scandium from the ion exchange resin to obtain a post-elution solution; an impurity extraction step in which after the elution step, the scandium-containing solution is subjected to a first solvent extraction using an amine-based impurity extractant and is separated into a first aqueous phase containing scandium and into a first organic phase containing impurities; and a scandium extraction step in which the first aqueous phase is subjected to a second solvent extraction using an amide derivative-containing scandium extractant to obtain a second organic phase containing scandium.

Methods and systems for recovering or extracting rare earth elements under mild conditions include subjecting a material including rare earth element to a rare earth element crystallization medium under solvothermal conditions sufficient to form rare earth element crystals capable of gravity separation and purification.