Abstract: A process designed to obtain potassium sulfate from vinasse where such vinasse is mainly obtained as a by-product of ethyl alcohol and the like production distilleries. Such process consists in concentrating vinasse dry solids for their subsequent combustion in a recovery boiler and to obtain electric power by activating a vapor turbine and at the same time recover the melted minerals from the boiler floor to obtain a chemical conversion reaction from carbonates to sulfates. Such reactions produce mainly Potassium sulfate in economic and technically sustainable production rates. Moreover, this process neutralizes the harmful effects of the vinasse polluting residue.

Abstract: Stabilized precursor solutions can be used to form radiation inorganic coating materials. The precursor solutions generally comprise metal suboxide cations, peroxide-based ligands and polyatomic anions. Design of the precursor solutions can be performed to achieve a high level of stability of the precursor solutions. The resulting coating materials can be designed for patterning with a selected radiation, such as ultraviolet light, x-ray radiation or electron beam radiation. The radiation patterned coating material can have a high contrast with respect to material properties, such that development of a latent image can be successful to form lines with very low line-width roughness and adjacent structures with a very small pitch.

Abstract: A pearlescent pigment and a process for enhancing the magnetic properties of a pearlescent pigment. The pearlescent pigment has a layer with regions of ?-Fe2O3 and regions of ?-Fe2O3. The magnetic properties of a pearlescent pigment may be enhanced by the steps of: providing a platelet pigment with a layer of Fe2O3, with a magnetic susceptibility less than 0.1×10?5 m3/kg; reducing some or all of the Fe2O3 to Fe3O4; and oxidizing some or all of the Fe3O4 to ?-Fe2O3. The color difference (?E*) between the provided pigment and the resultant pigment is not more than about 5.

Abstract: A process is disclosed for separation and recovery of vanadium, molybdenum, iron, tungsten, cobalt and nickel from alumina-based materials, mattes, ores, manufacturing by-products and waste. These elements are oxidized. The oxides are reacted with gaseous HCl to form volatile chloride-bearing compounds that subsequently sublimate. The volatile compounds are condensed in a downward-stepped thermal gradient that allows collection of moderate to high purity compounds of individual elements with exception of a nickel-cobalt co-condensate. Nickel is separated from cobalt by precipitation of nickel chloride from concentrated HCl pressurized with gaseous HCl.

Abstract: A method for recovering hydrochloric acid and metal oxides from a chloride liquor is described. The method uses a chloride liquor including the metal and mixing the liquor and a matrix solution to produce a reaction mixture, wherein the matrix solution assists oxidation/hydrolysis of the metal with HCl production. In a preferred embodiment the matrix solution includes zinc chloride in various stages of hydration and an oxygen containing gas is added to the mix. A method where the improvement is the mixing of a liquor and a matrix solution where the solution assists hydrolysis of the metal with HCl production is also disclosed. The reactor is a column reactor in a preferred embodiment. Further disclosed is the method of using the matrix solution and a reactor for recovering hydrochloric acid and for oxidizing/hydrolysis of a metal.

Abstract: Discolored organic compounds (DOC) may be extracted from a medium using a sorbent composition derived by sulfidation of red mud, which contains hydrated ferric oxides derived from the Bayer processing of bauxitic ores. In some aspects, the sorbent composition is slurried with the medium. In other aspects, the sorbent composition is formed into pellets or the like, which are contacted with the medium. The red mud (along with adsorbed contaminants) is then separated from the water using any suitable technique, such as filtration, sedimentation, or centrifugation.

Abstract: A method of recovering rhenium (Re) and other metals from Re-bearing materials in the form of ammonium perrhenate having at least the step of adding Re-bearing materials into a leaching slurry. Additionally, the method has the step of adjusting the pH of the slurry to obtain Re in soluble form in a metal salt solution and insoluble residues; filtering the metal salt solution to remove the insoluble residues; selectively precipitating Re from the metal salt solution; filtering the Re precipitate from the metal salt solution to obtain a Re filtercake; and formulating and drying the Re filtercake to obtain a Re sulfide product. The method further has the step of combining the Re sulfide product with a Molybdenum (Mo) concentrate containing Re to obtain a Mo/Re concentrate; roasting the Mo/Re concentrate to obtain Mo oxide product and a flue gas containing Re; and treating the flue gas containing Re to obtain ammonium perrhenate.

Abstract: A thermistor based on a composition having the general formula (I): Re2-x-yCraMnbMcEyOz wherein Re is a rare earth metal or a mixture of two or more rare earth metals, M is a metal selected from the group consisting of nickel, cobalt, copper, magnesium and mixtures thereof, E is a metal selected from the group consisting of calcium, strontium, barium and mixtures thereof, x is the sum of a+b+c and is a number between 0.1 and 1, and the relative ratio of the molar fractions a, b and c is in an area bounded by points A, B, C and D in a ternary diagram, wherein point A is, if y<0.006, at (Cr=0.00, Mn=0.93+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0?00, Mn=0.99, M=0.01), point B is, if y<0.006, at (Cr=0.83, Mn=0.10+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0.83, Mn=0.16, M=0.01), point C is at (Cr=0.50, Mn=0.10, M=0.40) and point D is at (Cr=0.00, Mn=0.51, M=0.49), y is a number between 0 and 0.5?x, and z is a number between 2.5 and 3.5.

Abstract: In a method for preparing a hydrogen absorbing electrode, a hydrogen absorbing alloy which contains a rare earth element as an alloy constituent and a transition metal element is immersed in an aqueous alkaline solution so that the saturation mass susceptibility is 1.0 to 6.5 emu/g of the hydrogen absorbing alloy. The hydrogen absorbing alloy is mixed through the immersing step with an oxide or hydroxide of a rare earth element wherein the oxide or hydroxide has as a main component at least one element selected from the group consisting of Dy, Ho, Er, Tm, Yb, and Lu. Then, a mixture of the hydrogen absorbing alloy and the oxide or hydroxide of the rare earth element is applied to form a desired shape.

Abstract: A solvent extraction composition comprising one or more orthohydroxyarylaldoximes and/or one or more orthohydroxyarylketoximes, and one or more selectivity modifiers consisting of phosphinic and/or phosphonic acids, and salts and esters therefore and optionally one or more equilibrium modifiers is provided.

Abstract: A process is disclosed for separation and recovery of vanadium, molybdenum, iron, tungsten, cobalt and nickel from alumina-based materials, mattes, ores, manufacturing by-products and waste. These elements are oxidized. The oxides are reacted with gaseous HCl to form volatile chloride-bearing compounds that subsequently sublimate. The volatile compounds are condensed in a downward-stepped thermal gradient that allows collection of moderate to high purity compounds of individual elements with exception of a nickel-cobalt co-condensate. Nickel is separated from cobalt by precipitation of nickel chloride from concentrated HCl pressurized with gaseous HCl.

Abstract: The present invention relates to processes for hydromethanating a nickel-containing (and optionally vanadium-containing) carbonaceous feedstock while recovering at least a portion of the nickel content (and optionally vanadium content) originally present in the carbonaceous feedstock.

Abstract: A method is provided for extracting nickel values from nickel-containing ores. The method comprises (a) treating a nickel-containing ore with an acid, thereby producing an acid treated ore; (b) baking the acid treated ore, thereby producing a baked ore; (c) leaching nickel from the baked ore to form a leachate; and (d) extracting nickel values from the leachate through the use of an ion exchange resin.

Abstract: In a non-aqueous electrolyte secondary battery comprising: a negative electrode containing, as a negative electrode active material, at least a material capable of absorbing and desorbing lithium ions or metal lithium; a positive electrode; and an electrolyte, an oxide containing nickel and manganese elements, the material comprising primary particles of the oxide having a twining portion and a superlattice arrangement of a [?{square root over ( )}3×?{square root over ( )}3] R30° when assigned as R3-m is used as a positive electrode active material.

Abstract: Toxic substances such as heavy metals are extracted from a medium using a sorbent composition. The sorbent composition is derived by sulfidation of red mud, which contains hydrated ferric oxides derived from the Bayer processing of bauxite ores. Exemplary sulfidizing compounds are H2S, Na2S, K2S, (NH4)2S, and CaSx. The sulfur content typically is from about 0.2 to about 10% above the residual sulfur in the red mud. Sulfidized red mud is an improved sorbent compared to red mud for most of the heavy metals tested (Hg, Cr, Pb, Cu, Zn, Cd, Se, Th, and U). Unlike red mud, sulfidized red mud does not leach naturally contained metals. Sulfidized red mud also prevents leaching of metals when mixed with red mud. Mixtures of sulfidized red mud and red mud are more effective for sorbing other ions, such as As, Co, Mn, and Sr, than sulfidized red mud alone.

Abstract: An improved process for the separation of different metal values from raw materials, and an apparatus for carrying out such processes are disclosed.

Abstract: The oxine ligands 5-chloro-8-hydroxyquiniline and 5-sulfoxyl-8-hydroxyquinoline are covalently bound, using, for example, the Mannich reaction, to a silica gel polyamine composite made from a silanized amorphous silica xerogel and polyallylamine. The resulting modified composites, termed CB-1 (X?Cl) and SB-1 (X?SO3H), respectively, show a clear selectivity for trivalent over divalent ions and selectivity for gallium over aluminum. The compounds of the invention can be applied for the sequestration of metals, such as heavy metals, from contaminated mine tailing leachates.

Abstract: Proppants which can be used to prop open subterranean formation fractions are described. Proppant formulations which use one or more proppants of the present invention are described, as well as methods to prop open subterranean formation fractions, and other uses for the proppants and methods of making the proppants.

Abstract: A method for recovering base metal values from oxide ore is provided, where the ore includes a first group metal selected from iron, magnesium and aluminum and a second group metal selected from nickel, cobalt and copper. The method includes reducing ore particle size to suit the latter unit operations, favoring contact of the metal elements, contacting the ore with ferric or ferrous chloride, hydrated or anhydrous, to produce a mix of ore and iron(II or III) chloride, subjecting the mixture of the ore and ferric or ferrous chloride to enough energy to decompose the chlorides into hydrochloric acid and a iron oxide, contacting the readily-formed hydrochloric acid with the base metal oxides from the second group, forming their respective chlorides, selectively dissolve the produced base metal chlorides, leaving the metals as oxides and in the solid state, and recovering the dissolved base metal values from aqueous solution.

Abstract: Disclosed are a nickel hydroxide powder and a method for producing the same. The nickel hydroxide powder comprises a particle in the form of sphere, an average particle diameter of 0.1 ?m or more and 30 ?m or less, and the amount of the particles having a diameter of 0.7 times or more and 1.3 times or less the average particle diameter of 80% by weight or more based on the total amount of particles. The method for producing a nickel hydroxide powder comprises the steps of (1) to (4): (1) injecting a solution containing a nickel salt through a pore into a liquid mutually insoluble with the solution to obtain an emulsion including solution as a dispersed phase and the liquid as a continuous phase; (2) gelating the emulsion; (3) separating the dispersed phase from the obtained gel to obtain a cake; and (4) drying the cake.

Abstract: A process for producing a purified nickel hydroxide precipitate from a nickel-containing leach solution with impurities including one or more of the following: manganese, copper, zinc, iron and/or cobalt, so that the purified nickel hydroxide is suitable for pelletization with iron-containing ores and/or stainless steel production, includes treating the leach solution with a base to form a slurry of mixed hydroxide precipitate and low-nickel barren solution, thickening the slurry to form filter cake, washing the filter cake and contacting it with acid to dissolve nickel and other metals to produce a concentrated nickel-containing solution, subjecting the concentrated nickel-containing solution to solvent extraction with an organic acid extractant to remove metals other than nickel from the nickel-containing solution and form a solvent extraction raffinate of purified nickel solution and treating the solvent extraction raffinate with a base to precipitate the purified nickel hydroxide precipitate.

Abstract: Provided is a roasting method capable of reducing both C and S components in minerals down to 0.5% or less, respectively, and securing a yield ratio of 90% or more for the Mo component. In a rotary kiln 7, a V, Mo and Ni containing material containing C and S components is subjected to oxidizing roasting to remove the C and S components from the material before reducing the material by means of a reducing agent in order to recover valuable metals composed of V, Mo and Ni. The rotary kiln is equipped with a burner 11 disposed on a material charge side 8a of the roasting furnace 8 to which the material is charged. In the roasting furnace, a direction along which the material moves and a flow of oxygen-containing gas introduced into the roasting furnace 8 are set to be parallel with each other.

Abstract: Disclosed is a method for preparation of a nickel-carbonitride sphere, which includes preparing a melamine-formaldehyde resin, adding a nickel salt and a surfactant to the melamine-formaldehyde resin to prepare a nickel-melamine resin mixture, and conducting spray pyrolysis for the mixture to produce nickel-containing powder including nickel-carbonitride spheres. In addition, this method may further include thermal treatment of the nickel-containing powder.

Abstract: The application of aqueous solution of magnesium bicarbonate and/or calcium bicarbonate in the process of extraction separation and purification of metals is disclosed, wherein the aqueous solution of magnesium bicarbonate and/or calcium bicarbonate is used as an acidity balancing agent, in order to adjust the balancing pH value of the extraction separation process which uses an acidic organic extractant, improve the extraction capacity of organic phase, and increase the concentration of metal ions in the loaded organic phase.

Abstract: A direct reduction process for a metalliferous material includes supplying the metalliferous material, a solid carbonaceous material, an oxygen-containing gas, and a fluidizing gas into a fluidized bed in a vessel and maintaining the fluidized bed in the vessel, at least partially reducing metalliferous material in the vessel, and discharging a product stream that includes the partially reduced metalliferous material from the vessel. The process comprises (a) reducing the metalliferous material in a solid state in a metal-rich zone in the vessel; (b) injecting the oxygen-containing gas into a carbon-rich zone in the vessel with a downward flow in a range of ±40° to the vertical and generating heat by reactions between oxygen and the metalliferous material (including metallized material), the solid carbonaceous material and other oxidizable solids and gases in the fluidized bed, and (c) transferring heat from the carbon-rich zone to the metal-rich zone by movement of solids within the vessel.

Abstract: The invention is a method of separating metals such as zinc, lead and cadmium from iron in secondary feed stocks such as EAF Dust, BOF Sludge, mill scale, iron fines, tire dust and other iron and zinc containing residues and dusts. The method includes the steps of reduction roasting the feed stocks at a volatizing temperature sufficient to volatilize the zinc and other metals into metal fumes but insufficient to volatize iron and then collecting the metal fumes as a metal dust. The metal dust is then leached with a leaching liquid to form a leach liquor and a leach residue. The leach liquor is then purified by zinc dust cementation to form a purified liquor and a zinc dust cement residue. The purified liquor is then separated from the zinc dust cement residue, and a zinc recovery step is then performed on the purified liquor.

Abstract: According to various embodiments of the present teachings, there is a metal-carbon nanotubes composite and methods of making it. A method of forming a metal-carbon nanotube composite can include providing a plurality of carbon nanotubes and providing a molten metal. The method can also include mixing the plurality of carbon nanotubes with the molten metal to form a mixture of the carbon nanotubes and the molten metal and solidifying the mixture of the carbon nanotubes and the molten metal to form a metal-carbon nanotube composite.

Abstract: The present teachings are directed towards a thermolysis method of producing iron-containing nanoparticles by providing an iron-containing component, a colloid stabilizing component, and an amount of water. The iron-containing component, the colloid stabilizing component, and the amount of water form a mixture, which is then heated to a temperature sufficient to form iron-containing nanoparticles, which are then isolated from the mixture. Another method is also provided which involves a repetitive shell growth method of producing iron-containing nanoparticles by providing a first amount of an iron-containing component and a colloid stabilizing component; the iron-containing component and the colloid stabilizing component are then mixed and heated to a temperature sufficient to form iron-containing nanoparticles.

Abstract: The subject of the present disclosure is a multi-column sequenced separation process and a drive for implementing this process. The disclosure applies particularly to the separation of metal derivatives such as uranium, nickel, copper, cobalt and other precious metals present in leaching effluents in hydrometallurgical processes.

Abstract: A method is provided for producing an agglomerated material that is used for producing metallic iron by heat reduction in a moving hearth-type reducing furnace, wherein the agglomerated material can have a high mechanical strength without increases in the binder content and the moisture content of the material mixture. The method for producing an agglomerated material used for producing metallic iron, wherein the agglomerated material is produced by agglomerating a material mixture containing an iron-oxide-containing material, a carbonaceous reducing agent, a binder, and moisture; drying the material mixture; and charging and heating the material mixture in a moving hearth-type reducing furnace to reduce the iron oxide contained in the material mixture with the carbonaceous reducing agent, wherein a carbohydrate is used as the binder and the material mixture is left to stand prior to the agglomeration.

Abstract: A method of producing a nickel product (including nickel alloy products and products such as nickel matte) from a nickel intermediate product is disclosed. The method comprises smelting a dried nickel intermediate product in a molten bath-based smelter and forming a molten pool containing a molten metal and a slag, with the molten metal being the nickel product. Intermediate and end products produced by the method are also disclosed.

Abstract: A process for the separation of nickel, cobalt or both from impurity elements selected from one or more of calcium, magnesium, manganese and chloride contained in a leach solution, the process comprising the step of subjecting the leach solution to solvent extraction using a carboxylic acid (such as Versatic 10), a hydroxyoxime such as LIX 63, a kinetic accelerator such as TBP, and optionally a stabilizer.

Abstract: Methods of treating spent pot lining (SPL) and bauxite residue are disclosed. The treatment processes are capable of producing a ferrosilicon alloy, an off-gas, and/or a byproduct material resulting in the safe disposal of SPL and bauxite residue. The treatment processes may be continuously carried out in an electric arc furnace at a temperature in the range of from about 1500° C. to about 2200° C. and for a period of from about 15 to about 100 minutes.

Abstract: A process for chlorinating ore, slag, mill scale, scrap, dust and other resources containing recoverable metals from the groups 4-6, 8-12, and 14 in the periodic table. The process comprises: a) forming a liquid fused salt melt consisting essentially of aluminum chloride and at least one other metal chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides, wherein the aluminum chloride content in the liquid salt melt exceeds 10% by weight; b) introducing the recoverable metal resources into said liquid salt melt: c) reacting the aluminum chloride as chlorine donor with said recoverable metal resource to form metal chlorides, which are dissolved in the salt melt; and d) recovering the formed metal chlorides from the salt melt.

Abstract: A method of separating nickel bearing sulphides from mined ores or concentrates of mined ores that contain talc is disclosed. The method comprises treating a slurry of mined ores or concentrates of mined ores in at least one flotation stage and in at least one cleaner circuit. The method further comprises sequenced re-grinding, as described herein, of particles in the slurry.

Abstract: A process for treating a finely particulate, in particular metal-containing, charge material: The charge material and a treatment gas, in particular a reduction gas, are introduced into a fluidized bed chamber of a fluidized bed reactor to form a fluidized bed. After at least partial reaction in the fluidized bed, the treatment gas is discharged from the fluidized bed and, outside the fluidized bed, is at least partially reprocessed, preferably oxidized, by an exothermic, chemical reaction with a reactant, preferably with a gaseous and/or liquid oxidizing agent. The thermal energy of this reaction is at least partially introduced into the fluidized bed chamber, in particular into the fluidized bed, or being discharged therefrom to affect the temperature of the particulate material above the bed. Also an apparatus for operating such a fluidized bed includes the chamber, lines into and out of the chamber for gas and material and a cyclone at the chamber for the material.

Abstract: The invention relates to a method of making a nickel powder having an average particle size of less than about 100 nanometers, comprising contacting, at a temperature of about 50° C. to about 95° C., a reduction solution with a nickel solution to form a reaction mixture. The reduction solution comprises a base and a reducing agent. The nickel solution comprises a nickel compound water, a nucleation agent, a surfactant or dispersant, and combinations thereof. The yield of nickel nanoparticles is greater than about 90% relative to starting moles of nickel compound. The nickel powder is suitable for use in electronics applications and sintered metal applications.

Abstract: Disclosed are compositions and methods for separating gangue material from metallic sulfide ores. The compositions typically include a lignosulfonate and do not include a cyanide salt. Suitable lignosulfonates may include lignosulfonates, for example hardwood lignosulfonate having a weight average molecular weight of about 3 kDa to about 12 kDa and having a relatively low sulfur content and a relatively low sulfonate content.

Abstract: The present invention relates to a process for the removal of metal catalyst degradation products from a bleed stream of a catalytic chemical reaction process, wherein the catalyst is based on a metal selected from those in group VIII of the periodic table, chromium, copper, molybdenum, tungsten, rhenium, vanadium, titanium and zirconium, said process comprising treatment of the bleed stream with an alkali metal carbonate or ammonium carbonate source to form a solid complex or an aqueous solution of said solid complex, and removal of the solid complex or the aqueous solution of said solid complex from the bleed stream.

Abstract: In a hydroformylation reaction, the circulation and recovery of cobalt carbonyl in a cobalt catalyst cycle using carbonylate as an intermediate and acidification thereof, is improved by supplying an aqueous sulfuric acid solution containing less than 16% wt of sulfuric acid to the carbonylate to control sulfuric acid concentration in the carbonylate/acid mixture, before accounting for any acid consuming reaction, to a value of from 2% to 10% by weight. Single step and multistage liquid/liquid extraction techniques as well as vapour/liquid extraction techniques followed by the absorption of cobalt from the vapour in an organic liquid both benefit from this improvement.

Abstract: A method for preparing lithium transitional metal oxides, comprises the steps of: preparing a carbonate precursor using the following substeps: forming a first aqueous solution containing a mixture of at least two of the ions of the following metal elements (“Men+”): cobalt (Co), nickel (Ni), and manganese (Mn); forming a second aqueous solution containing ions of CO32?; and mixing and reacting the first solution and the second solution to produce the carbonate precursor, Ni1-x-yCoxMnyCO3; and preparing the lithium transition metals oxide from the carbonate precursors using the following substeps: evenly mixing Li2CO3 and the carbonate precursor; calcinating the mixed material in high temperature; and cooling and pulverizing the calcinated material to obtain the lithium transition metal oxide, Li Ni1-x-yCoxMnyO2.

Abstract: A process for the recovery of nickel and cobalt from laterite ores, the process including the steps of: a) beneficiating the ore to separate it into a beneficiated upgraded ore fraction and a coarse, siliceous low grade rejects fraction which is substantially free from fines and clay materials; b) separately processing the upgraded ore fraction for the recovery of nickel and cobalt; and c) subjecting the low grade rejects fraction to a heap leach process with an acid supplemented solution to create a heap leachate for further nickel and cobalt recovery processing.

Abstract: A novel solution route has been developed that after heat-treatment to 500-600° C. under inert atmosphere, yields highly porous composites of nano-sized metal (Ni) particle inclusions in ceramics (Al2O3). Metal loadings could be made from <1% to >95% Ni. The metal inclusion sizes in the Ni—Al2O3 system with the 10 atom % Ni sample were 4-7 nm, while for the 75 atom % Ni sample they were 5-8 nm. It was shown that the 10 atom % Ni sample could be used as a catalyst for the conversion of CO2 and CH4 in the temperature range 550-700° C., while higher temperatures led to growth of the Ni particles and carbon poisoning over time. The solution routes could also be deposited as thin dense films containing <10 nm Ni particles. Such films with high Ni-particle loadings deposited on aluminium substrates have shown very good solar heat absorber proficiency and provide good substrates for carbon tube growth.

Abstract: The invention provides a lithium-manganese-based composite oxide containing Ti and Ni, which is represented by the compositional formula: Li1+x(Mn1?n?mNimTin)1?xO2, wherein 0<x?0.33, 0.05<m<0.3, and 0.3<n<0.5, and includes a crystal phase of layered rock-salt type structure. The composite oxide is a novel material that is capable of maintaining an average discharge voltage of 3 V or more over long charge/discharge cycles, while providing a discharge capacity equal to or higher than those of lithium-cobalt-oxide-based positive electrode materials, and that can be prepared using starting materials that are inexpensive and less limited as natural resources, while exhibiting improved charge/discharge characteristics over known low-cost positive electrode materials.

Abstract: A process is disclosed for separation and recovery of vanadium, molybdenum, iron, tungsten, cobalt and nickel from alumina-based materials, mattes, ores, manufacturing by-products and waste. These elements are oxidized. The oxides are reacted with gaseous HCl to form volatile chloride-bearing compounds that subsequently sublimate. The volatile compounds are condensed in a downward-stepped thermal gradient that allows collection of moderate to high purity compounds of individual elements with exception of a nickel-cobalt co-condensate. Nickel is separated from cobalt by precipitation of nickel chloride from concentrated HCl pressurized with gaseous HCl.

Abstract: A method of producing an iron-arsenic compound by adding an oxidizing agent to an aqueous solution containing arsenic ions and bivalent iron ions and allowing an iron-arsenic compound precipitation reaction to proceed under stirring of the solution, wherein the precipitation reaction is terminated at a solution pH in the range of 0 to 1. When the arsenic concentration of the pre-reaction solution is 25 g/L or greater, the reaction can be terminated at a solution pH in the range of ?0.45 to 1.2. The pH of the pre-reaction solution is preferably greater than 0 and not greater than 2.0. A ferrous sulfate is can be used as the source of the bivalent iron ions. Even when some amount of impurity elements is present in the arsenic-containing solution, the method is nevertheless capable of forming a scorodite compound excellent in crystallinity in the form of a compact compound barely swollen by moisture and the like, i.e., a niron-arsenic compound excellent in filterability.

Abstract: A metal sulfide nanocrystal manufactured by a method of reacting a metal precursor and an alkyl thiol in a solvent, wherein the alkyl thiol reacts with the metal precursor to form the metal sulfide nanocrystals, wherein the alkyl thiol is present on the surface of the metal sulfide nanocrystal, wherein the alkyl thiol is bonded to the sulfur crystal lattice. A metal sulfide nanocrystal manufactured with a core-shell structure by a method of reacting a metal precursor and an alkyl thiol in a solvent to form a metal sulfide layer on the surface of a core, wherein the alkyl thiol is present on the surface of the metal sulfide nanocrystal, wherein the alkyl thiol is bonded to the sulfur crystal lattice. These metal sulfide nanocrystals can have a uniform particle size at the nanometer-scale level, selective and desired crystal structures, and various shapes.

Abstract: A method of treating value bearing material comprising oxidised or surface oxidised mineral values includes the steps of crushing the value bearing material, contacting the crushed material! with a sulfide solution to sulfide the oxidised or surface oxidised mineral values, and adding ions of a selected base metal to the crushed value bearing material. The value bearing material may comprise oxidised or surface oxidised base metal or precious metal minerals. The crushed value bearing material is prepared as a slurry or pulp comprising from 15% to 40% solids and the remainder comprising water. The sulfide solution preferably comprises a soluble sulfidiser such as sodium hydrosulfide and the base-metal ion solution preferably comprises metal salt of base metals like copper or iron.

Abstract: The present invention relates to a zero-waste process for extraction of alumina from different types of bauxite ores and red mud residues and of titanium dioxide from ilmenite. Iron oxide is first reduced to metallic iron above the melting point of C-saturated cast iron alloy which yields a high-C iron alloy and an Al and Ti metal oxide rich slag which is then treated with alkali carbonate to form alkali aluminates and titanates. The alkali aluminates are separated by water leaching from which the hydroxide of alumina is precipitated by bubbling CO2. The residue from water leaching is treated with sulphuric acid and TiO2 is precipitated via a hydrolysis route. The process recovers most of the metal values and generates only small quantities of silicious residues at pH4-5 which can be used for soil conditioning.

Abstract: The present invention relates to a particulate mixed metal hydroxide that includes nickel, cobalt and aluminium. The powder particles have a core of nickel/cobalt hydroxide, and a surface that is coated with amorphous aluminium hydroxide. A process for the continuous preparation of such mixed metal hydroxides is also described. The process includes precipitating aluminium hydroxide in the presence of a nickel/cobalt mixed hydroxide in a tube reactor. The mixed metal hydroxides of the present invention may be used to prepare active materials for positive electrodes of a secondary battery.