A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising countercurrently contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted.

A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising countercurrently contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted.

A temperature-regenerated hydrophobic liquid composition includes an extracting molecule of a non-alkaline cationic species, a solvating molecule of a complimentary anionic species and a fluidizing agent. The extracting molecule of a non-alkaline cationic species is a macrocycle of which the ring is formed from 24-32 carbon atoms and has the following formula (I) or (II): wherein —n is an integer ranging from 5 to 8, —p is 1 or 2, —m is 3 or 4, —q and t, which may be identical or different, are 0, 1 or 2, —R is a tert-butyl, tert-octyl, O-methyl, O-ethyl, O-propyl, O-isopropyl, O-butyl, O-isobutyl, O-pentyl, O-hexyl, O-heptyl, O-octyl, or OCH.sub.2Phenyl group or a hydrogen atom, and —R′ and R″, which may be identical or different, are chosen from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, heptyl and octyl groups or R′ and R″ together form a pyrrolidine, piperidine or morpholine ring.

Methods and apparatus for integrated alkali metal extraction are disclosed. Various exchange media are used to separate a chosen alkali metal, usually lithium, from a source stream and render the alkali metal into a product. In some cases, absorption/desorption processes, using solid and/or liquid absorption media, are used to purify a brine stream into a concentrate stream having elevated concentration of the desired alkali metal. Various processes, which may include use of liquid absorbents, electrochemical processing, centrifugation, evaporation, electrical mixing and separation, or combinations thereof, are used to separate the chosen metal from the source, and aqueous streams are recycled among the processes to facilitate the various separations.

A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted; recovering the rare earth metal from the non-aqueous phase; and processing the recovered rare earth metal into a rare earth metal oxide.

A composite extractant-enhanced polymer resin comprising an extractant and a polymer resin for direct extraction of valuable metals such as rare earth metals, and more specifically, scandium, front an acid-leaching slurry and/or acid-leaching solution in which ferric ions are not required to be reduced into ferrous ions. The extractant may be cationic, non-ionic, or anionic. More specifically, the extractant di(2-ethylhexyl)phosphoric acid may be used. The polymer resin may be non-functional or have functional groups of sulfonic acid, carboxylic acid, iminodiacetic acid, phosphoric acid, or amines. The composite extractant-enhanced polymer resin may be used for extraction of ran earth metals from acid-leaching slurries or solutions.

A process for recovering gold from a gold-containing raw material, comprising leaching the gold-containing material with an aqueous solution comprising elemental bromine and bromide source to form a pregnant leach solution with the gold dissolved therein; separating said pregnant leach solution from the gold-depleted raw material, removing elemental bromine from said pregnant leach solution, extracting the gold from the pregnant leach solution in an acidic environment into an organic extractant, to form a gold-loaded extract and bromide-containing raffinate, stripping the extract with an alkaline aqueous solution to form a gold-bearing aqueous solution, generating gold (Au.sup.0) and treating bromide-containing stream(s) to produce recyclable elemental bromine.

A process for recovering gold from a gold-containing raw material, comprising leaching the gold-containing material with an aqueous solution comprising elemental bromine and bromide source to form a pregnant leach solution with the gold dissolved therein; separating said pregnant leach solution from the gold-depleted raw material, removing elemental bromine from said pregnant leach solution, extracting the gold from the pregnant leach solution in an acidic environment into an organic extractant, to form a gold-loaded extract and bromide-containing raffinate, stripping the extract with an alkaline aqueous solution to form a gold-bearing aqueous solution, generating gold (Au.sup.0) and treating bromide-containing stream(s) to produce recyclable elemental bromine.

A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.

A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.