Abstract: A method for magnetic ore separation and/or dressing is provided, in which metalliferous recoverable materials are separated from conveyed metalliferous ore rock.

Abstract: Embodiments of the invention relate to a method of making a mineral product. The method includes contacting a carboxylic acid and an inorganic mineral compound sufficient to form a solution, reacting the solution over a period of time sufficient to provide a mineral chelated compound, transferring the mineral chelated compound to one or more molds prior to the compound substantially solidifying and reducing the size of the mineral chelated compound sufficient to provide a rapidly soluble mineral chelated product.

Abstract: A process for producing an anisotropic magnetic material includes: preparing a feebly magnetic material capable of transforming into a magnetic material by a prescribed reaction, orienting the feebly magnetic material by imparting an external field to the feebly magnetic material, and transforming the oriented feebly magnetic material to a magnetic substance by the prescribed reaction.

Abstract: Methods and apparatuses for separating metal values, such as nickel and nickel compounds, from mineral ores, including lateritic ores are disclosed. The method includes providing a mixture of particles (e.g., crushed and sized ore) that is composed of at least a first group of particles and a second group of particles. Group members have similar chemical composition, while particles belonging to different groups have dissimilar chemical compositions. The mixture of particles is concurrently, or generally concurrently, heated (using microwave/millimeter wave energy) and exposed to a reactant. The wave energy and the reactant act to increase the difference in either the magnetic susceptibility or other separation properties between the first and second group of particles. The mixture of particles is then passed through an appropriate separator to separate the particles of interest. Optional steps are disclosed for purifying selected particles.

Abstract: A reactor 20 has a plurality of tubular downcomers 32, 34, 36, 38, 40 and risers 42, 44, 46, 48, 50, joined by sections 86, 88 in a continuous serpentine path the tubes dimensioned to provide substantially plug flow conditions for solid and liquid reagents fed into a first downcomer 24 with the products extracted from final riser 52. The reactor 20 is designed for a desired residence time by the number, height and diameter of the tubes. The downcomers 24, 32, 34, 36, 38, 40 may include a bend to improve residence time and to thereby reduce the number of tubes required for a desired overall residence time. The reactor 20 can be used in a leaching operation for producing synthetic rutile, where a pre-treated feedstock including ilmenite, leueoxene or titania slag is leached with hot HCl.

Abstract: A production process for an oxide magnetic material comprising the steps of blending raw material powder so as to take the composition of a hexagonal ferrite including: at least one kind of an element A selected from the group consisting of Ba, Sr and Ca; Co and Cu; Fe; and O; and sintering said blended powder at a temperature lower than 1000° C.

Abstract: Methods and apparatuses for separating metal values, such as nickel and nickel compounds, from mineral ores, including lateritic ores are disclosed. The method includes providing a mixture of particles (e.g., crushed and sized ore) that is composed of at least a first group of particles and a second group of particles. Group members have similar chemical composition, while particles belonging to different groups have dissimilar chemical compositions. The mixture of particles is exposed to microwave/millimeter wave energy in order to differentially heat the first and second group of particles, thereby increasing differences in magnetic susceptibility between the first and second group of particles. The mixture of particles is then passed through a magnetic field gradient, which causes the particles to separate into magnetic and non-magnetic fractions.

Abstract: The method for separating ferrate salts from a solution comprising providing contact between the solution of essentially of aqueous hydroxide and the ferrate salts and a surface having a magnetic attraction, magnetically securing the ferrate salts to the surface; and eliminating contact between the solution and the surface. Contact is provided by immersing the surface in the solution, passing the liquid ferrate mixture over the surface, or combinations thereof. The magnetic attraction may be induced by permanent magnets, electromagnets, and combinations thereof. The apparatus for ferrate production comprises an electrochemical cell having an iron-containing anode, cathode, and an aqueous hydroxide solution in fluid communication with both the anode and the cathode, and a magnetic separator in fluid communication with the aqueous hydroxide solution for separating ferrate salts from the aqueous hydroxide solution.

Abstract: Spindle-shaped magnetic metal particles containing iron as a main component of the present invention, have an average major axis diameter (L) of 0.05 to 0.15 &mgr;m; a coercive force of 111.4 to 143.2 kA/m; a Co content of from 0.5 to less than 5 atm % based on whole Fe; a crystallite size of from 150 to less than 170 Å; a ratio of Al to Co from 1.0:1 to less than 2.0:1; a specific surface area (S) represented by the formula: S≦−160×L+65; an oxidation stability (&Dgr;&sgr;s) of saturation magnetization of not more than 5.0%; and an ignition temperature of not less than 140° C. The spindle-shaped magnetic metal particles containing iron as a main component, exhibit an adequate coercive force, and are excellent in dispersibility, oxidation stability and coercive force distribution despite fine particles, especially notwithstanding the particles have an average major axis diameter as small as 0.05 to 0.15 &mgr;m.

Abstract: A magnetite-iron based composite powder includes magnetite with a ratio of X-ray diffraction intensity to that of &agr;-Fe of about 0.001 to about 50 and has an average primary particle size of about 0.1 to about 10 &mgr;m. The composite powder can highly dehalogenate organic halogen compounds and exhibits satisfactory absorption power of high frequency electromagnetic waves after molding. An ultrafine nonferrous inorganic compound powder may adhere to the surface of the composite powder, or at least the composite powder may adhere to the surfaces of small particles of a nonferrous inorganic compound to thereby yield a composite powder composition. The composite powder can be produced by partial reduction of a material powder containing a hematite based powder or by complete reduction and subsequent partial oxidation of the material powder.

Abstract: A two-step chemical precipitation process involving hydroxide precipitation and sulfide precipitation combined with “field separation” technology such as magnetic separation, dissolved air flotation, vortex separation or expanded plastics flotation, effectively removes chelated and non-chelated heavy metal precipitates and other fine particles from water. In the first-step, the non-chelated heavy metals are precipitated as hydroxides and removed from the water by a conventional liquid/solids separator such as an inclined plate clarifier to remove a large percentage of the dissolved heavy metals. The cleaned water is then treated in a second precipitation step to remove the residual heavy metals to meet discharge limits. In the second precipitation step, any metal precipitant more effective than hydroxide for metal precipitation can be used.

Abstract: Spindle-shaped magnetic metal particles containing iron as a main component, having an average major axis diameter (L) of 0.05 to 0.15 &mgr;m; a coercive force of 111.4 to 159.2 kA/m; a Co content of from 5 to less than 15 atm % based on whole Fe; a crystallite size of from 150 to less than 170 Å; a ratio of Al to Co from 0.3:1 to less than 2.0:1; a specific surface area (S) represented by the formula: S≦−160×L+65; an oxidation stability (&Dgr;&sgr;s) of saturation magnetization of not more than 4.5%; and an ignition temperature of not less than 145° C. The spindle-shaped magnetic metal particles containing iron as a main component, exhibit an adequate coercive force, and are excellent in dispersibility, oxidation stability and coercive force distribution despite fine particles, especially notwithstanding the particles have an average major axis diameter as small as 0.05 to 0.15 &mgr;m.

Abstract: A magnetic material made up of an assembly of particles substantially consisting of an &agr;″-Fe16N2 crystal having a body-centered tetragonal system (bct). The magnetic material has a high saturated magnetic flux density and is directly synthesized by reacting fine particles of &agr;-Fe and a nitrogen-containing gas at a temperature of 200° C. or lower. By the synthesis of this invention, &agr;″-Fe16N2, which is a metastable compound conventionally deposited accompanied with phase transformation of crystallization from a martensite phase of &agr;′-Fe(N), is obtained as an isolated bulk substance in a single phase.

Abstract: A process and an apparatus for the production of iron oxides having low chloride ion content comprising charging of a free HCl containing iron chloride solution into a spray roaster with a feeding device and a spray boom for charging the iron chloride containing solution into a reaction chamber heated by combustion gases thermally decomposing the solution into iron oxide, HCl gas and reaction gases a discharging device for the iron oxide and a cooling zone between the burner's focal plane and the discharging device cooling of iron oxide granules to temperatures at less than 450.degree. C. reducing the concentration of HCl gas to less than 10 volume percent charging the layer of iron oxide granules onto a conveyor plate charged with hot steam and feeding the exhaust gases into the central combustion duct of the spray roaster. The resulting iron oxide has a residual chloride ion content of less than 500 ppm Cl.sup.- and a specific surface area in excess of 3.5 m.sup.3 /g.

Abstract: Coloring pigment of comparable quality to, and cheaper than, pigments products by chemical precipitation, is made from synthetic magnetite produced by oxidation of ferrous mill scale and reduced to a particle size such that preferably at least 85% of the product does not exceed 10 microns and 95% does not exceed 20 microns. The smaller the particle size the greater the tinting strength of the pigment. The pigment may be black or, by calcination of the synthetic magnetite, it may be red. For best quality the black pigment should contain 95-99.5% iron oxides, typically, and the magnetite should have a molecular ratio of 0.9 to 1.1:1. The shade and hue of red is dependent upon the calcination temperature and final size and shape of the particles. Reduction to the required particle size for the red coloring pigment may be done before and/or after calcination.

Abstract: A process for producing ultra-fine barium hexaferrite particles. In the first step of this process, a ceramic precursor material containing barium and trivalent ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A method for preparing a perpendicularly magnetizable material usable on magnetic recording media comprises the steps of: dissolving at least one member of the group consisting of strontium chloride and strontium nitrate with at least one member of the group consisting of iron chloride and iron nitrate in distilled water; adding citric acid to the resultant solution; controlling the pH of the solution to a range sufficient to completely dissociate the citric acid; heating the resultant solution with stirring to yield a gelatinous precursor; and subjecting the precursor to a temperature sufficiently high to remove the organic constituents thereof, which is characterized by controlling the pH of the solution to gelate the solution without the use of ethylene glycol, and can provide a perpendicularly magnetizable material superior in magnetic and particle properties.

Abstract: A process for beneficiation of titaniferous ores is disclosed in which a titanium and iron-containing ore, such as ilmenite is heated with potassium hydroxide, e.g. at temperatures of about 350.degree.-650.degree. C. and then treating the product with carbon monoxide and water. After cooling and washing the solid product can be separated by magnetic means into an iron-containing magnetic fraction and a titanium-containing fraction.

Abstract: A method for producing high-purity iron oxide which comprises pulverizing iron ore into powder having an average particle diameter of 20-150 .mu.m, removing fine particles from the powder, and subjecting the powder to wet magnetic separation in a magnetic field of 1000-15000 gauss for the removal of impurities. The iron oxide powder may undergo the secondary steps of pulverization and classification, which are performed by the combination of a wet grinding means and a wet cyclone, and drying and calcination.

Abstract: The iron content of the TiO.sub.2 -containing precursor is subjected to a direct reduction to effect a metallization of at least 90%. The reduced product is separated into magnetic and nonmagnetic fractions by magnetic separation. To oxidize the metallic iron, the magnetic fraction is subjected to an oxidation in an acid medium with agitation at a pH value below 2, under a pressure of 12 to 24 bars, and at a temperature from 150.degree. to 210.degree. C. with a supply of an oxygen-containing gas that contains at least 90% oxygen. When the suspension has been pressure-relieved, the hematite which has been formed is separated from the TiO.sub.2 concentrate.

Abstract: A process for the preparation of ferromagnetic metallic particles for magnetic recording which comprises(I) a step of preparing a slurry of acicular iron oxide hydrate containing nickel and, if necessary, manganese,(II) a step of coating the surface of the above iron oxide hydrate with aluminum-containing iron oxide hydrate, thus giving a slurry containing the coated iron oxide hydrate and free aluminate ions,(III) a step of depositing aluminum and phosphorus and/or silicon on the outside surface of the aluminum-containing iron oxide hydrate, thereby giving a slurry of the iron oxide hydrate thus treated,(IV) a step of subjecting the slurry to washing, drying and dehydrating, reducing the obtained particles, and forming an oxide layer on the surface of the reduced particles.

Abstract: A process for treating and recovering pickling waste liquids used for the pickling of stainless steel such as nitric-hydrofluoric acid, nitric acid, hydrochloric acid and, sulfuric acid is disclosed, which comprises recovering the nitric-hydrofluoric acid and the iron oxide or metallic ion from the waste liquids of nitric-hydrofluoric acid and nitric acid by two solvent extraction processes and recovering the Cr and Ni containing ferrite from the waste liquids of sulfuric acid or hydrochloric acid by a ferrite formation process. When the waste acid is sulfuric acid, gypsum of a high purity can be obtained.

Abstract: A process for producing magnetic metallic oxide which comprises the steps of pulverizing at least one member selected from the group consisting of ferro-manganese, ferro-nickel, electrolytic manganese, electrolytic iron and electrolytic zinc, adding to the substance thus pulverized at least one member selected from the group consisting of oxides of Fe, Mn, Ni, Cu, Mg, Zn and Co and salts of Fe, Mn, Ni, Cu, Mg, Zn and Co which become oxides by heating, wet pulverizing and mixing the mixture upon oxidation, thereby producing a slurry, and heating said slurry at 800.degree. to 1450.degree. C. By this process, a magnetic ferrite can be stably and inexpensively synthesized.

Abstract: A process for production of metallic iron by heating ammonium iron fluoride or iron fluoride in hydrogen stream.

Abstract: Recovery of cobalt and manganese metal oxidation catalysts from residue of trimellitic acid manufacture and separation of recovered cobalt from recovered manganese can be accomplished by a novel method involving dissolving the residue in water, displacing dissolved cobalt as cobalt metal by manganese metal added to the solution whose pH has been adjusted to pH of 6 and then using magnetic means for separating metallic cobalt from the cobalt-free solution.

Abstract: Cobalt and manganese are recovered from incineration ash obtained by combustion of residue from the manufacture of trimellitic acid and its recovery as 4-carboxyphthalic anhydride and then the recovered cobalt is separated from the recovered manganese by magnetic separation. The foregoing is accomplished by extraction of the ash with an aqueous solution of hydrogen bromide or chloride, recovery of the extract solution, and the upward adjustment of its pH while adding powdered manganese to precipitate metallic cobalt for its separation by magnetic means.

Abstract: A unique method of separating cobalt and manganese from residue obtained from the manufacture of trimellitic acid by the oxidation of pseudocumene in the presence of cobalt and manganese as metal oxidation catalysts and from each other without contributing to the problem of solids disposal. Said unique method comprises extracting the residues with water, removing cobalt and mangangese from the extract solution with a cation exchanger thereby producing a metal-free solution of trimellitic acid, regenerating the cation exchanger with a strong inorganic acid, adjusting the pH of the spent regenerating acid to pH of 3 to 4 if iron is present to precipitate it as its hydroxide but at least to pH of 6 while also adding powdered manganese to precipitate metallic cobalt.

Abstract: Recovery of cobalt and manganese from residue of trimellitic acid manufacture and recovery as 4-carboxy-phthalic anhydride by extracting the residue with an aqueous alkaline solution containing carbonate ions which leaves a precipitate of metal carbonates, dissolving said precipitate as the metal chlorides, and at an upwardly adjusted pH adding powdered manganese to precipitate metallic cobalt and separating it by magnetic means.

Abstract: A process for thermal activation of chalcopyrite-pyrite ore concentrates for activation of iron values in both chalcopyrite and pyrite constituents whereby said iron values can be selectively removed in a subsequent acid leach. Controlled oxidizing conditions are maintained in an oxidizing heating zone for removal of up to about 90% of total sulfur to be removed for conversion of pyrite and chalcopyrite to their acid-leachable forms, measured by a preferable oxidation of 10 to 15% of iron in the concentrate to ferromagnetic oxides, whereby remaining total sulfur to be removed is removed in a reducing zone with the assistance of a low H.sub.2 S/(H.sub.2 +H.sub.2 S) ratio by scavenging of H.sub.2 S by said oxides.

Abstract: A method for producing metallic oxide compounds having a spinel type structure by reacting the beta form of hydrated iron oxide with a salt of an effective metallic cation.

Abstract: Minerals, for example, zirconium minerals, are subjected to a chemical process of comminution, in particular with the aid of strong acids. These acids dissolve the carbonatic and silicious cements which hold together the crystalline forms of different mineral species from one another, e.g., magnetic and non-magnetic species to render them amenable to further separation in a subsequent ore dressing stage, e.g., by high intensity magnetic separation. This process is operative as these cements dissolve in acid more readily than most of the other compounds of the ores. This separation was found to take place more effectively than by the usual methods of mechanical grinding and without the disadvantage of an unfavorable particle size distribution which results from grinding. It was found that the same process conditions also resulted in a particularly favorable removal of naturally occurring radioactive contaminants from the minerals, in particuar thorium and uranium.

Abstract: A process is disclosed for preparing magnetite having an equiaxial morphology and a narrow particle size dispersion by precipitation from a ferrous sulphate solution, characterized in that:A. during a first step, at a temperature between 15.degree. and 40.degree. C, alkali is added to the ferrous sulphate solution, in a stoichiometric amount adapted to precipitate, in the form of ferrous hydroxide, 2/3 of the Fe.sup.+.sup.+ ion, and then, at the conclusion of said precipitation, air is blown thereinto thus oxidizing ferrous hydroxide to goethite .alpha.FeO(OH); andB. during a second step, alkali is added to the slurry obtained in the first step, the remaining Fe.sup.+.sup.+ is precipitated in the form of ferrous hydroxide, and the slurry is heated to a temperature between 70.degree. and 100.degree. C, thus causing the formation of magnetite which is then separated from the solution.

Abstract: An animal feed supplement containing cobalt in polarized form enhances the efficient utilization of protein by ruminant animals and promotes their growth. In a preferred form, the supplement consists essentially of the reaction product of cobalt carbonate and lactic acid admixed with a diatomaceous earth and a sacchariferous substance.

Abstract: The invention concerns the preparation of acicular particles of mixed oxalates of iron and of one or more metals of the group consisting of cobalt, nickel, copper, manganese, zinc, magnesium and cadmium. The method consists in preparing a first solution containing cations of iron and of the divalent metal or metals, and a second solution containing oxalic acid, one of the said solutions further containing Cl.sup.- and SO.sub.4.sup.2.sup.- anions and at least the second solution containing alcohol with preferably a light hydrocarbon. The first solution is poured very slowly (1 drop every 10 seconds) into the second one, conveniently at temperature below 0.degree. C, while the latter is strongly stirred. The concentration in alcohol is preferably maintained at at least 50% in the second solution during the whole pouring process which should be effected with at least a slight excess of oxalic acid.

Abstract: An improved process for the production in high yield of activated carbon particles of high activity comprises rapid removal of volatile material from the area of carbonaceous particles during the carbonization step by individually venting each hearth of a multiple hearth furnace. The carbonaceous particles which are subjected to the carbonization step are prepared from mixtures of carbonaceous material and petroleum acid sludge.

Abstract: The processes for producing iron oxide products from a solution of ferrous salts selected from the group consisting of waste liquid containing ferrous salts and aqueous solution in which ferrous salts obtained from the waste liquid are dissolved, under the acid, wet and high ferrous concentration conditions. More particularly, the processes for purifying said waste liquids comprising the bivalent iron removing steps.