Abstract: A new system in which a forward extraction part, a scrubbing part, and a backward extraction part operate together and synchronously to produce specific substances by extraction and separation in a liquid-liquid system. The aqueous phase is circulated independently only in the forward extraction part one or more times, and the organic phase is circulated from the forward extraction part through the scrubbing part and the backward extraction part to the forward extraction part again in synchronization with the liquid circulation of the aqueous phase.

Abstract: 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-(C8 to C14 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.

Abstract: The invention relates to a method for producing metal nanoparticles, wherein metal ions are reduced by means of at least one reducing agent in the presence of at least one polymer stabilizer and are converted into metal nanoparticles. The invention further relates to metal nanoparticles obtained in this way and to the use thereof.

Abstract: The present invention provides a method for producing silver nanoparticles by employing ethanolamine. The method of this invention can be easily operated and no organic solvent is required. Ethanolamine first reacts with a mixture of poly(oxyalkylene)-amine/epoxy or copolymers of poly(styrene-co-maleic anhydride) (abbreviated as SMA) to generate polymeric polymers. The polymeric polymers then reduce silver ions to silver atoms which are dispersed in the form of silver nanoparticles. Functional groups of the polymeric polymers can chelate with silver ions and be stably compatible with water or organic solvents, whereby the silver nanoparticles can be stably dispersed without aggregation and the produced silver nanoparticles.

Abstract: A method is provided for separating the impurities zinc, iron, calcium, copper and/or manganese from an aqueous solution that contains cobalt and nickel. The solution is brought into a mixing contact with an extraction solution, which is pre-loaded with cobalt and nickel ions, whereby the cobalt and nickel in the extraction solution are replaced with the impurity metals, and the aqueous solution is cleaned from impurities after this phase. This purified aqueous solution, raffinate, can be used to pre-charge the extraction solution so that a minor part of the raffinate is contacted with a pre-neutralized extraction solution, whereby the cobalt and nickel replace the alkali metal, alkali earth metal or ammonium ion that is used in the pre-neutralization.

Abstract: A process for hydro-extracting non-ferrous metals from a slurry, pulp or solution, the process including a resin which is a copolymer of a polystyrene and a non-styrenic polymer, wherein the non-styrenic polymer includes the following subunit: Formula (I) wherein Rb is a divalent linking group, preferably alkylene, and most preferably (—CH2—CH2—; and Rd is NH, NR, O or absent. Preferably the resin has an acrylic backbone.

Abstract: Solvent extraction from an aqueous phase containing first and second rare earth elements is carried out by contacting an organic phase containing a diglycolamic acid as an extractant and a hydrocarbon or a low-polar alcohol as a solvent, with the aqueous phase below pH 3 for extracting the first rare earth element into the organic phase, back-extracting from the organic phase with an aqueous acid solution for recovering the first rare earth element, and recovering the second rare earth element which has not been extracted into the organic phase and has remained in the aqueous phase.

Abstract: The present invention provides a method for manufacturing metal nanoparticles, comprising: dissociating at least one metal precursor selected from the group consisting of silver, gold and palladium; reducing the dissociated metal precursor; and isolating the capped metal nanoparticles with an alkyl amine. The present invention provides a method for manufacturing metal nanoparticles which can be performed with simpler equipment compared to the gas phase method, can provide metal nanoparticles in high yield by only using alkyl amine without using any surfactant in high concentration which further allows mass production, and can provide metal nanoparticles having high dispersion stability and uniform size of 1-40 nm.

Abstract: A method for separation and recovery of noble metals which makes it possible to isolate noble metal components efficiently by easy operation, that is, a method which comprises passing a solution of metals in hydrochloric acid prepared by treating a metal material with hydrochloric acid through the first cellulose column, eluting through development the noble metal component adsorbed on the cellulose with a hydrochloric acid/2-propanone mixture to obtain a fraction containing light platinum-group metals and a fraction containing heavy platinum-group metals and gold, separating the former fraction with the above mixture into fractions containing palladium, ruthenium and rhodium respectively, passing the fraction containing heavy platinum-group metals and gold through the second cellulose column to made them adsorbed on the cellulose, eluting them from the cellulose with a hydrochloric acid/1-butanol mixture to obtain fractions containing gold, osmium, iridium and platinum respectively, and recovering the noble

Abstract: Processing for the extraction of metals consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, rhenium and gold (PGMRA) includes dissolution of the PGMRA metals from solid materials in an acidic aqueous solution, preferably with a halogen acid sparged with the corresponding halogen element. The acidic solution is then exposed to extraction material of non-cross-linked polyamine composite resin. The bound metal, following washing of the extraction material is eluted from the resin using stronger acidic processes than that provided in the wash of the resin. Conventional extraction by organic solvents or other known techniques is employed to recover the PGMRA metals. Rhodium is separated from the rest of the PGMRA metals either near the beginning or the end of the process. Rhodium is separated by creating hydroxides with the metals in the solution and then reacidifying the metals such that the rhodium remains as aquochlororhodate complexes.

Abstract: Processing for the extraction of metals consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, rhenium and gold (PGMRA) includes dissolution of the PGMRA metals from solid materials in an acidic aqueous solution, preferably with a halogen acid sparged with the corresponding halogen element. The acidic solution is then exposed to extraction material of non-cross-linked polyamine composite resin. The bound metal, following washing of the extraction material is eluted from the resin using stronger acidic processes than that provided in the wash of the resin. Conventional extraction by organic solvents or other known techniques is employed to recover the PGMRA metals. Rhodium is separated from the rest of the PGMRA metals either near the beginning or the end of the process. Rhodium is separated by creating hydroxides with the metals in the solution and then reacidifying the metals such that the rhodium remains as aquochlororhodate complexes.

Abstract: A composition useful for the extraction of metals and metalloids comprises (a) carbon dioxide fluid (preferably liquid or supercritical carbon dioxide); and (b) a polymer in the carbon dioxide, the polymer having bound thereto a ligand that binds the metal or metalloid; with the ligand bound to the polymer at a plurality of locations along the chain length thereof (i.e., a plurality of ligands are bound at a plurality of locations along the chain length of the polymer). The polymer is preferably a copolymer, and the polymer is preferably a fluoropolymer such as a fluoroacrylate polymer. The extraction method comprises the steps of contacting a first composition containing a metal or metalloid to be extracted with a second composition, the second composition being as described above; and then extracting the metal or metalloid from the first composition into the second composition.

Abstract: The present invention relates to a powder of unagglomerated metallic particles. More particularly, the present invention relates to a powder of unagglomerated metallic particles having an average diameter of about 1-100 nm and the process for making the same. Additionally, the powder of unagglomerated metallic particles can be formed into a lyophilized form which upon reconstitution maintains the average diameter of between about 1-100 nm wherein the particles remain unagglomerated.

Abstract: Metal ions and/or complexes of metal ions are removed from a solution by formation of an insoluble chelated complex of the metal ions and a polymeric precipitating agent. A two-step process of mixing the influent with the precipitating agent is used to induce rapid precipitation and obtain large, self-agglomerated precipitate without addition of flocculating agent and/or pH adjustment. In addition, parallel loops are employed to simultaneously discharge treated metal-free solution and effectively collect/remove the precipitate-containing sludge without interfering with each other. The metal capturing capacity of the polymeric precipitant is maximized by forcing the influent solution through layers of the collected precipitate and by recycling unsaturated metal-precipitant complexes in the processing loop.

Abstract: The present invention relates to a powder of unagglomerated metallic particles. More particularly, the present invention relates to a powder of unagglomerated metallic particles having an average diameter of about 1-100 nm and the process for making the same. Additionally, the powder of unagglomerated metallic particles can be formed into a lyophilized form which upon reconstitution maintains the average diameter of between about 1-100 nm wherein the particles remain unagglomerated.

Abstract: An improved method for extracting a precious metal from mineral fines by heap leaching with dilute sulfuric acid which comprises agglomerating the mineral fines prior to formation into a heap with an agglomerating agent composition comprising sequential addition of a first polymer selected from the group consisting of anionic and nonionic water-soluble polymers and then a second cationic water-soluble polymer to the fines. Preferred first polymers are poly(acrylamide) and 70/30 mole percent poly(acrylamide/sodium acrylate), and preferred second polymers are poly(diallyldimethylammonium chloride), 90/10 mole percent poly(acrylamide/diallyldimethylammonium chloride) and 99/1 mole percent poly(diallyldimethylammonium chloride/vinyltrimethoxysilane).

Abstract: Spent solutions from photographic processors are fed into a conduit (18) to which subsequently are added precipitating agents from a first source (22) and flocculating agents from a second source (28); so that, well grown or ripened clumps of flocculated solids are formed along the conduit before being emptied into a gravity collecting vessel and shipping container (38) from which clarified liquids are displaced by a mass (50) of accumulated flocculated solids, typically through a filter (58, 142, 150, 158, 162, 166, 220)for removal of any unsettled fines. Many of the clumps of flocculated solids become enlarged enough to individually extend across and substantially fill a cross-sectional area of the conduit. As a result, the enlarged clumps substantially block passage of and strain from the solution remaining fine particles which then adhere to the clumps.

Abstract: A process for the percolation leaching of minerals from a mineral-beating ore comprises agglomerating the mineral-bearing ore with an agglomerating agent of a cationic block copolymer having a polymeric segment and a block containing an ammonium cation optionally with a block derived from an acrylamide monomer, forming the ore/agglomerating agent mixture into a heap, and leaching the heap by percolation with a leaching solution for subsequent recovery of the minerals at an acidic pH.

Abstract: The invention provides submicron particles. The invention further provides submicron particles which are dispersed in an aqueous colloid. The invention further provides a method of forming the stable dispersion which includes providing an ion exchange resin, loading the ion exchange resin with an ion, treating the loaded resin to form nanoscale particles. The invention further provides fluidizing the resin and particles to form an aqueous stable colloid.

Abstract: Agglomerating agent and method for use in heap leaching of mineral bearing ores. Cationic polymers alone or in combination with cement or lime are highly effective agglomerating agents in acidic or alkaline leaching operations. The cationic polymers are preferably graft copolymers, block copolymers or linear copolymers of acrylamide and diallyl dimethyl ammonium chloride.

Abstract: An improved process for dissolving gold metal in ligand and oxidant lixiviation systems, wherein the solubility of gold is enhanced by the addition of heterocyclic aromatic compounds containing nitrogen or sulfur in the ring.

Abstract: Carbonaceous pyropolymers possessing recurring units containing at least carbon and hydrogen atoms on their surface are effective in removing from solution metal cations having a standard reduction potential to their zerovalent state of greater than -0.2 volts. Their mode of action appears to be via reduction of the metal to the zerovalent state which then is deposited on the pyropolymer surface.

Abstract: A method of selectively separating lead ions from metal ions-containing aqueous liquid by contact with a solution containing a polyether derivative dissolved in a water-insoluble organic solvent and serving as an ionophore or carrier for lead ions. The polyether derivative is a compound expressed by the general formula: ##STR1## wherein R.sub.1 and R.sub.2 stand independently from each other for a hydrogen atom or an alkyl group and n is an integer of 2 or 3.

Abstract: A method for the recovery of a metal from an organic complex thereof, said method comprising treating the complex with a weakly acid aqueous solution of an alkali metal or alkaline earth metal chloride having a chloride content of at least 4 molar whereby said complex is decomposed and metal ions are transferred to the aqueous solution.

Abstract: Rhodium and certain other PGM's in oxidation state III complex with chloride is precipitated from a solution by mixing with a polyamine, especially diethylene-triamine, in the presence of a protonating agent for the polyamine. High selectivity and high yields, in comparison to known reagents, are observed.

Abstract: Recovery of precious metals such as gold and silver from aqueous cyanide solutions thereof, by contact with a reagent containing a guanidine functionality. The guanidine reagent extracts the precious metal from the aqueous solution which is subsequentily stripped from the guanidine reagent and recovered by conventional methods. Certain novel guanidine compounds suitable for extracting gold and silver are disclosed.