Abstract: A process is described for the preparation of powder mixtures or composite powders from at least one first type of powder from the group consisting of high-melting metals, hard materials and ceramic powders and at least one second type of powder from the group consisting of binder metals, binder-metal mixed crystals and binder-metal alloys, where the second type of powder is formed from precursor compounds in the form of water-soluble salts in an aqueous suspension of the first type of powder by precipitation as oxalate, removal of the mother liquor and reduction to the metal.

Abstract: The invention concerns ultrafine polymetallic particles obtained from reducing a mixture of salts dissolved in an organic solvent by an alkali or alkaline earth metal hydride, at a temperature not higher than the solvent reflux temperature, the mixture of dissolved salts comprising at least a salt of a metal having a standard oxidant potential E°Mn+/M at 25° C. higher than −1.18 V. The invention is applicable to the hydrogenation of olefins and the coupling of halogenated aromatic derivatives.

Abstract: The present invention is a polyol method for making composite particles of two or more immiscible transition metals, where these particles are of nanoscale dimensions, and where the constituent metals are of essentially nanocrystalline morphology. The method of the invention has the steps of (1) dissolving or suspending two or more precursor metal compounds in an alcohol or polyol (diol, triol, etc.) solution, and (2) taking the solution or suspension to a temperature where the metal compound reduces, causing the first and second metals to form nanoscale composites. The term “polyol solution” will be used herein to describe solutions that contain either alcohol or polyol.

Abstract: A method for forming metal particles and fibers, including: mixing at least one of nanotubes and nanofibers with at least one metal salt to form a mixture, and decomposing and reducing the mixture. The method of syntheses metal nanoparticles and fibers, such as Cu, Pd, Pt, Ag and Au nanoparticles and Cu sub-micron fibers, by using carbon nanotubes or carbon nanofibers as templates.

Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic solvents under an inert atmosphere to provide highly uniform particles and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines. Effective production is obtained at atmospheric pressure and at temperatures as low as 50° C. with xylene solvent. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species.

Abstract: A nickel fine powder includes 0.02 to 1.0% by weight of magnesium and/or 0.02 to 0.1% by weight of calcium dispersed in the nickel. A method for preparing the nickel fine powder includes the steps of forming nickel hydroxide by mixing an aqueous solution containing a magnesium salt and/or a calcium salt and a nickel salt with an aqueous solution of sodium hydroxide and then reducing the hydroxide with a hydrazine reducing agent. The nickel fine powder has thermal shrinkage characteristics very close to those observed for ceramic substrates and is accordingly suitable as a material for producing an internal electrode for laminated ceramic condensers.

Abstract: A method for producing metal powder which involves the step of making an alkaline hydroxide, hydrazine or a hydrazine hydrate, and a metallic salt co-exist in a solvent comprising an alcohol, at least a portion of each being dissolved; wherein, in the step, metal powder comprising a metal contained in the metallic salt is precipitated by reducing the metallic salt with the hydrazine or the hydrazine hydrate. By the above method, a metal powder having a particle size of about 100 nm or less can be obtained and the metal powder is not contaminated with impurities originating from the reducing agent.

Abstract: A method for the chemical precipitation of metallic silver powder employs a two solution technique in which a solution of a tin salt and a solution a silver salt are mixed in the presence of an inorganic or organic acid, alumina, an anionic surfactant, and a colloid to form a precipitation solution at a temperature and pH suitable to effect the chemical precipitation of silver. Almost 80% by weight of the precipitated powder agglomerate is less than 25 .mu.m in diameter, and the individual powder particles which compose the agglomerate range in size from 0.2 to 2.0 .mu.m. In addition to the favorable size distribution, silver particles precipitated in the presence of a gelatin colloid can be used with a minimal amount of sieving so that little work hardening is imparted to the particles. The powder can be annealed at a temperature of up to 750.degree. C.

Abstract: An agent for treating metal ions in an aqueous solution, which comprises an anthrahydroquinone compound and a metal supported on a carbonaceous carrier.

Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic olvents under an inert atmosphere to provide highly uniform particles and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species.

Abstract: A method is provided for producing molybdenum metal powders having consistently high tap densities. The method involves doping an ammonium molybdate solution with a soluble potassium compound, forming an ammonium dimolybdate precipitate and reducing the precipitate to form a metal powder.

Abstract: A method of producing a non-metal element or a metal or an alloy thereof from a halide or mixtures thereof. The halide or mixtures thereof are contacted with a stream of liquid alkali metal or alkaline earth metal or mixtures thereof in sufficient quantity to convert the halide to the non-metal or the metal or alloy and to maintain the temperature of the reactants at a temperature lower than the sintering temperature of the produced non-metal or metal or alloy. A continuous method is disclosed, particularly applicable to titanium.

Abstract: X-ray amorphous and nanocrystalline elemental metal powders of groups IB to VIIIB of the Periodic Table are prepared by reacting halides of these metals with alkali metal hydrides or alkaline earth metal hydrides in an organic solvent with continual milling.

Abstract: A method comprising the steps of solvent extracting a gold bearing chlorination leach solution with DBC, scrubbing the resulting gold bearing organic phase with hydrochloric acid and reducing gold is capable of recovering gold in high purity by:(1) adjusting the concentration of hydrochloric acid in the gold bearing chlorination leach solution to 0.5-1.75 N before the solvent extraction and then scrubbing the resulting gold bearing organic phase with 0.25-0.75 N hydrochloric acid; and/or(2) performing five-stage scrubbing with hydrochloric acid by either one of the following three approaches: i) after three-stage scrubbing, centrifugal separation is effected and separation is then performed by filtration with a filter having an opening size of 0.05-5 .mu.m, with the resulting organic phase being then subjected to two-stage scrubbing; ii) after five-stage scrubbing, centrifugal separation is effected and separation is then performed by filtration with a filter having an opening size of 0.05-5 .mu.

Abstract: The present invention relates to a process for obtaining an iron powder, which may incorporate nickel and/or cobalt, by organic liquid phase precipitation. This process comprises a stage of introducing metal precursors into a basic polyol or optionally simple alcohol solution, a stage of heating said reaction medium to obtain a metal precipitate and a stage of recovering and treating said precipitate to obtain the desired powder.

Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic solvents under an inert atmosphere to provide highly uniform particles selectably sized from about 65 nm to about 500 nm and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials including composites, super thermite, and other explosives. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines being believed effective. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Increased production rate is achieved at higher temperatures. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective.

Abstract: In order to produce precious metal powders of uniform particle size and low BET specific surface, appropriate aerosols are introduced into a flame reactor, whereby the aerosols are first freed of solvent as completely as possible by a thermal treatment.

Abstract: To essentially eliminate aluminum and silicon as contaminants in a doped tungsten wire, the tungsten wire is obtained by mechanical working of reduced tungsten blue oxide which contains as a primary or major constituent a special hexagonal ammonium tungsten bronze of the general formula (NH.sub.4).sub.X (NH.sub.3).sub.y WO.sub.3. A liquid doping step is carried out by adding a solution containing potassium nitrate, the special doped ammonium tungsten bronze forming preferably more than 70% by weight of the overall tungsten blue oxide. The special hexagonal ammonium tungsten bronze is made by decomposing ammonium paratungstate in an ammonium atmosphere, preferably at a temperature between about 400.degree. and 550.degree. C.

Abstract: To dope ammonium paratungstate with potassium, essentially devoid of silicon and ammonium, an aqueous potassium containing solution, preferably potassium hydroxide is added to an aqueous solution of ammonium paratungstate (APW), in a mol relationship of potassium to ammonium of between 0.1 and 10. A doped ammonium potassium paratungstate (AKPW) is obtained. This ammonium potassium paratungstate is then converted to tungsten blue oxide, which is reduced, preferably in a hydrogen containing atmosphere and a tungsten powder is then obtained which will be doped with 40 to 120 ppm, preferably about 90 ppm of potassium. Lamps equipped with tungsten wire filaments drawn from so doped tungsten have lifetimes at least 10% more than lamps with conventional tungsten filaments.

Abstract: A method of producing a non-metal element or a metal or an alloy thereof from a halide or mixtures thereof. The halide or mixtures thereof are contacted with a stream of liquid alkali metal or alkaline earth metal or mixtures thereof in sufficient quantity to convert the halide to the non-metal or the metal or alloy and to maintain the temperature of the reactants at a temperature lower than the lesser of the boiling point of the alkali or alkaline earth metal at atmospheric pressure or the sintering temperature of the produced non-metal or metal or alloy. A continuous method is disclosed, particularly applicable to titanium.

Abstract: Nanostructured metal powders and films are made by dissolving or wetting a metal precursor in an alcoholic solvent. The resulting mixture is then heated to reduce the metal precursor to a metal precipitate. The precipitated metal may be isolated, for example, by filtration.

Abstract: There is disclosed a method for preparing a powder containing ammonium salts of W+Co(Ni) complex ions, through chemical reactions, in a water solution at temperatures from 70.degree. C. to the boiling point and at pH around neutral, between tungstate salts and cobalt (nickel) salts characterized in that said tungstate salts are the highly soluble sodium tungstate or ammonium metatungstate.

Abstract: The invention is directed to a method for the manufacture of substantially fully densified, finely divided particles of gold wherein the operating temperature is below the melting point of gold.

Abstract: A method for producing fine silver-palladium alloy powder includes the steps of: (A) preparing separately a silver nitrate solution and a palladium nitrate solution and mixing the solutions, and then adding a neutralizing and complexing agent to the mixed solutions to adjust the pH thereof to about 2.5-3.5, whereby a first mixture containing silver and palladium ions is obtained; (B) preparing a second mixture containing a reductant and a surfactant; (C) bringing the first mixture into contact with the second mixture at a reaction temperature of 15.degree.-50.degree. C. under stirring in order to permit the silver and palladium ions to be reduced and to coprecipitate so as to form silver-palladium alloy particles; and (D) recovering the coprecipitated silver-palladium alloy particles, thereby obtaining the fine silver-palladium alloy powder.

Abstract: A electroless plating method of an Ni--Al intermetallic compound includes steps of a) providing a reducing solution containing a reducing agent and reducing nickel ions, b) adding a proper amount of aluminum powder to the reducing solution, and c) permitting the reducing agent to reduce the reducing nickel ions to be deposited on the aluminum powder. Such electroless plating method permits the Ni--Al compound to be produced inexpensively/efficiently/fastly.

Abstract: First, an aqueous solution of water soluble compounds or an aqueous solution of water soluble complexes, which is a salt of elements belonging to the 6A, 7A, 1B, 2B, 3B, 4B, 5B, 6B, or 8 group in a periodic table are prepared. The pH of the aqueous solution is adjusted and titanium trichloride is added thereto. The aqueous solution provided with titanium trichloride is stirred at temperature below the boiling point of the solution under atmospheric pressure or under high pressure. Then, by the reducing action of the titanium trichloride, a fine titanium-free powder selected from the group consisting of a metal powder, an alloy powder containing two or more of metals and non-metals, or a compound powder containing two or more of metals and non-metals is obtained.

Abstract: A method for the manufacture of fully densified, finely divided particles of silver-palladium alloy comprising the sequential steps:A. Forming an unsaturated solution of a mixture of thermally decomposable silver-containing compound and a thermally decomposable palladium-containing compound in a thermally volatilizable solvent;B. Forming an aerosol consisting essentially of finely divided droplets of the solution from step A dispersed in a carrier gas, the droplet concentration which is below the concentration where collisions and subsequent coalescence of the droplets results in a 10% reduction in droplet concentration;C.

Abstract: Silver powder with a controlled surface area is made by introducing a silver ion containing solution and a mixed solution containing reducing agents and surfactants into a low temperature tank of 5.degree.-20.degree. C. and holding for a period of 7-60 minutes, followed by introducing the resulting reaction solution into a high temperature tank and holding further. The rest potential of the reaction solution is monitored to determine the end point of the reaction.

Abstract: A process for recovering palladium, rhodium and ruthenium from aqueous solutions deriving from the treatment of nuclear fuels and containing also iron and nickel, by reducing carbonylation with carbon monoxide at a pressure up to 1 atmosphere in a nitric acid solution at a pH of between 2 and 4 and at a temperature of between room and 100.degree. C. and reaction times of from 6 to 100 hours.

Abstract: A method for the preparation of finely divided, dense packing, spherical shaped silver particles comprising the sequential steps of:(1) reacting an aqueous mixture of a silver salt with an alkanolamine to form a homogeneous aqueous solution of a dissolved silver alkanolamine complex;(2) preparing an aqueous solution of a reducing agent and, optionally, an alkanolamine; and(3) mixing together the silver alkanolamine complex solution and the reducing agent alkanolamine solution at a buffered pH and a temperature of 10.degree. C. to 100.degree. C. to form finely divided spherical silver particles.

Abstract: A novel zerovalent zinc species and an organozinc reagent are disclosed. The zerovalent zinc species is directly produced by reaction of a reducing agent on a zinc salt, preferably Zn(CN).sub.2. The organozinc reagent results from the reaction of the zerovalent zinc species and an organic compound having one or more stable anionic leaving groups. These organozinc reagents include a wide spectrum of functional groups in the organic radical, and are useful in a variety of reactions schemes.

Abstract: The present invention relates to a process for preparing silver-palladium powders that may be used for the production of electrode materials, contacts or the like used in the electronic industries. The process comprises the steps of forming an acid solution containing silver and palladium ions; adding the acid solution while stirring to an aqueous solution containing a hydrazine and a surfactant system; and forming reduction-separated silver-palladium fine powders having an average particle diameter less than 1.0 micron and a specific surface area lower than 6.0 m.sup.2 /g.

Abstract: A reductive process for making finely divided silver particles in which the silver particles are precipitated from an aqueous acid solution of silver salt containing silica sol.

Abstract: A method for producing pure cobalt metal powder involves the removal of divalent cationic impurities from a trivalent hexamine cobalt chloride solution. This solution is then decomposed to an insoluble cobalt oxide-containing material, from which pure cobalt metal powder is obtained through a chemical reduction process.

Abstract: The invention relates to a method for producing metal powders, where the employed raw materials are metal ions in a liquid phase. According to the invention, at a preliminary stage of the method the liquid phase containing metal ions is reduced with hydrogen at an increased pressure and raised temperature in order to produce porous, sponge-like metal powder. The obtained porous, sponge-like metal powder is further processed at a high temperature, for instance by means of plasma, in order to improve the qualities of the metal powder.

Abstract: Disclosed is a graded metal powder for metallic pigment, comprising a metal powder wherein the metal powder has a mean particle size of from about 2.5 to about 15.0 .mu.m, the content of particles having a particle size of not greater than 1 .mu.m is not larger than about 0.5% by volume, and the metal powder has a particle size distribution such that not smaller than 97% by volume of the particles of the metal powder fall within the range between half the mean particle size of the metal powder and double the mean particle size of the metal powder. Also is disclosed a process for producing a graded metal powder by classifying metal particles dispersed in a mineral oil containing a nonionic-anionic surfactant.

Abstract: Process to obtain ultra fine magnetic Nd-Fe-B particles of various sizes, which can cause a reaction in different kinetic conditions, between compounds of Nd, Fe and B in the sine of micro-emulsions formed by water, oil and a surface-active agent, in different thermodynamic conditions.

Abstract: A reductive process for making finely divided silver particles in which the silver particles are precipitated from an aqueous acidic solution of silver salt, gelatin and alkyl acid phosphate.