Abstract: The present invention relates to a tyre for vehicle wheels comprising at least one structural element comprising a cross-linked elastomeric material obtained by cross-linking a cross-linkable elastomeric composition comprising carbon nanotubes, wherein said carbon nanotubes are obtained with an iron oxides and/or aluminium oxides based catalyst substantially free of Co, Ni and Mo.

Abstract: An annealing method is provided. The annealing method includes preparing a metal oxide structure, annealing the metal oxide structure in a gas atmosphere including nitrogen to fabricate a metal compound structure, an oxygen content of which is lower than that of the metal oxide structure, from the metal oxide structure, and annealing the metal compound structure in a gas atmosphere including oxygen to fabricate a nitrogen-doped metal oxide structure, which has a specific surface area greater than that of the metal oxide structure, from the metal compound structure.

Abstract: The current invention concerns a method for increasing an iron content of a solution by converting low iron containing solutions into highly concentrated ferric chloride solutions by adding iron containing substances. The invention concerns also methods for transporting and storage of said highly concentrated ferric chloride solutions.

Abstract: The present invention relates to a method for recovering vanadium and tungsten from a leach solution of a waste denitrification catalyst, and more specifically, to a method for recovering vanadium and tungsten from a leach solution of a waste denitrification catalyst comprising the steps of: recovering vanadium by adding acid and then adding a calcium compound to a leach solution of a waste denitrification catalyst to precipitate the vanadium; and recovering tungsten by adding acid and then adding a calcium compound to the remaining leach solution after recovering the vanadium to precipitate the tungsten.

Abstract: Provided is a device for producing partially reduced iron, with which partially reduced iron having a prescribed reduction ratio can be produced efficiently. The present invention is equipped with: CO sensors that detect the carbon monoxide concentration in an exhaust gas; an O2 sensor that detects the oxygen concentration in an exhaust gas; an exhaust gas circulation device that adjusts the circulating amount of the exhaust gas supplied to a reduction furnace main body, and an air feed device that adjusts the amount of air that being fed; and a control device that controls these devices. The control devices on the basis of the carbon monoxide concentration in the exhaust gas as detected by the CO sensor and the oxygen concentration in the exhaust gas as detected by the O2 sensor.

Abstract: A method of manufacturing a graphene film manufactures a graphene film in good state without generating wrinkles and stresses and leaving residues of the resin. The method of manufacturing a graphene film comprises forming a catalyst metal film on a substrate; synthesizing a graphene film on the catalyst metal film; and removing the metal catalyst film in an oxidation atmosphere of an oxidizer and transferring the graphene film to the substrate.

Abstract: A method for recovering alkali and aluminum during treatment of Bayer red mud using a calcification-carbonation method, including steps of mixing the Bayer red mud with calcium aluminate or with calcium aluminate and lime, performing calcification dealkalization conversion in a high-concentration alkaline liquor, and carbonizing the calcified residues produced during dealkalization to obtain carbonized residues; and then performing low-temperature aluminum dissolution, aluminum precipitation and the like to obtain calcium aluminate products, which is returned to the calcification dealkalization conversion of the red mud for recycling. Part of an alkali-containing and aluminum-containing liquid phase after calcification dealkalization conversion can be used as supplementary alkali in the Bayer production course for recycling. The method is energy-saving and environmentally-friendly, and allows recovering alkali and aluminum from the red mud and harmless treatment of the Bayer red mud.

Abstract: A process is provided for obtaining a hematite-containing material that can be used for ironmaking. The process includes separating a leach residue from a hydrometallurgical refining plant into an overflow and an underflow using a wet cyclone under a condition that the wet cyclone is adjusted to have a setting between 1 ?m or less and 2 ?m or less as a classification particle size for the overflow. The process then includes separating the overflow into a strong magnetic substance and a weak magnetic substance using a strong-magnetic-field magnetic separator under a condition that magnetic field intensity is 5 to 20 [kGauss]. The process then includes using a superheated steam drying system for adjusting a moisture content of the strong magnetic substance after the separation, to be 10 wt % to 17 wt %.

Abstract: The invention relates to a process for obtaining material of value from a bauxite residue which is obtainable or has been obtained by the Bayer process. This process comprises the steps of a) providing an aqueous suspension of the bauxite residue, b) setting a pH of the suspension to a value between 7.2 and 12.2, c) at least partly deagglomerating suspended mineral agglomerates of the bauxite residue, and d) separating the resulting mixture into an iron-rich fraction and into at least one further, preferably silicate-rich fraction. The invention further relates to an apparatus (10) for carrying out the process.

Abstract: A method is provided for separating a leach residue from which a hematite-containing material capable of being used as a raw material for ironmaking can be obtained. A method also is provided for producing hematite for ironmaking from the leach residue. The method utilizes a leach residue as a raw material, the leach residue being obtained from a hydrometallurgical refining plant where a nickel oxide ore treated by a high pressure acid leach process. The method includes, in sequence: a separation step of separating the leach residue into an overflow and an underflow with a wet cyclone; and another separation step of separating the separated overflow into a strong magnetic substance and a weak magnetic substance using magnetic force, wherein a strong-magnetic-field magnetic separator is used in the another separation step using the magnetic force.

Abstract: The invention is a low binder, wear resistant material including, in weight percent of raw materials, from 15% to 20% of molybdenum carbide added in either elemental or compound form, an alloy of 0.9% to 3% cobalt, nickel or a combination of cobalt and nickel, of 0 to 0.1% of chromium carbide, optionally also titanium carbide or titanium tungsten carbide and the balance of tungsten carbide.

Abstract: The present invention generally relates to cathodes used to produce chlorine gas from gaseous hydrogen chloride. The cathode comprises a cathode electrolyte comprising Fe(II) compounds and Fe(III) compounds in contact with an electron conductor. A reactor comprises a reactor solution comprising an oxidant in fluid contact with the cathode electrolyte. The fluid contact of the reactor solution with the cathode electrolyte allows the cathode electrolyte rich in Fe(II) compounds to be transferred to the reactor and combined with the reactor solution and the reactor solution rich in Fe(III) compounds to be transferred from the reactor to the cathode electrolyte after the oxidant of the reactor solution reacts with the electrolyte rich in Fe(II) compounds to form the reactor solution rich in Fe(III) compounds.

Abstract: A method of recovering base metals from sulphide ores and concentrates includes mixing the base metals ore with ferric salts, heating the mixture, adding water to form a pulp, and stirring and filtering the pulp.

Abstract: The present invention provides a method of separating nickel bearing sulphides from mined ores or concentrates of mined ores that contain talc particles is disclosed. The method comprises adjusting the Eh of a slurry of mined ores or concentrates of mined ores and making particles of nickel bearing sulphides less hydrophobic than talc particles and floating the nickel bearing sulphide particles from the slurry.

Abstract: The invention is directed to a pulverulent compound of the formula NiaM1bM2cOx(OH)y where M1 is at least one element selected from the group consisting of Fe, Co, Zn, Cu and mixtures thereof, M2 is at least one element selected from the group consisting of Mn, Al, Cr, B, Mg, Ca, Sr, Ba, Si and mixtures thereof, 0.3?a?0.83, 0.1?b?0.5, 0.01?c?0.5, 0.01?x?0.99 and 1.01?y?1.99, wherein the ratio of tapped density measured in accordance with ASTM B 527 to the D50 of the particle size distribution measured in accordance with ASTM B 822 is at least 0.2 g/cm3·?m. The invention is also directed to a method for the production of the pulverulent compound and the use as a precursor material for producing lithium compounds for use in lithium secondary batteries.

Abstract: A composite particle and a population of particles comprising a water-insoluble polyphosphate composition, methods of producing, and methods of using the same are provided. The polyphosphate composition may comprise at least one alkaline earth metal selected from calcium and magnesium and optionally at least one nutrient ion selected from the group consisting of potassium, ammonium, zinc, iron, manganese, copper, boron, chlorine, iodine, molybdenum, selenium or sulfur.

Abstract: A method for recovering cobalt, ruthenium, and aluminum from spent Co—Ru/Al2O3 catalyst. First, Co—Ru/Al2O3 spent catalyst is subjected to hydrocarbon removal, reaction with hydrogen, and alkali fusion to obtain a slag. The slag is subjected to acid leaching, precipitation of cobalt with oxalic acid or ammonium oxalate, reduction of cobalt oxalate, and dissolution of cobalt metal with nitric acid to obtain Co(NO3)2.6 H2O. The effluent of acid leaching is subjected to reaction with ethanol, filtration to obtain a filtrate and residue, dissolution of the residue with concentrated hydrochloric acid, and vacuum distillation to obtain ?-RuCl3.x H2O. Aluminum hydroxide is prepared from the filtrate through carbonation and calcination. The cobalt yield is ?97%; the ruthenium yield is ?95%, and the aluminum yield is ?92%.

Abstract: In a device and a process for purifying water which is contaminated with sulphate ions and heavy metal ions, the water is collected in a water reservoir and a substance having basic activity in water is fed to the water reservoir in such a manner that a precipitant having heavy metal ions is precipitated from the water, wherein at least a subquantity of water is taken off from the water reservoir and is separated into pure water which is substantially freed from sulphate ions and heavy metal ions and dirty water which is enriched with sulphate ions and heavy metal ions. The dirty water is at least in part recirculated to the water reservoir, as a result of which a concentration of sulphate ions in the water reservoir is achieved such that a precipitant having sulphate ions is precipitated from the water.

Abstract: A process for recovering a metal chloride or mixed metal chloride from a solid waste material comprising recoverable metal containing constituents produced by lead, copper or zinc smelting and refining processes, said process comprising the steps of: (i) heating the solid waste material; (ii) treating the heated material of step (i) with a gaseous chloride to form a gaseous metal chloride containing product; and (iii) treating the gaseous metal chloride containing product of step (ii) to recover the metal chloride or mixed metal chloride. The metal chloride may be further treated to extract the metal itself.

Abstract: A method and a device for reducing iron-oxide-containing feedstocks, in which a reducing gas is fed to a reducing unit (1) containing the iron-oxide-containing feedstocks. The reducing gas is generated by introducing a process gas having reduction potential into a heating appliance (3) for heating the process gas, which is withdrawn as reducing gas therefrom. In the heating appliance (3), heat energy is transferred to the process gas. The heat energy is formed by combustion of a fuel gas containing organic substances, including coke oven gas with addition of technically pure oxygen. The flames of the combustion have an adiabatic flame temperature of above 1000° C., wherein, in the combustion of the fuel gas, at least some of the organic substances present in the fuel gas are cracked.

Abstract: A nickel recovery loss reduction method that makes it possible to reduce nickel recovery loss by lowering the concentration of fine floating solid components in overflow liquid in precipitating and separating treatments, and consequently to further reduce a nickel recovery loss, a hydrometallurgical method for nickel oxidized ore to which the nickel recovery loss reduction method is applied, and a sulfurizing treatment system. The present invention is a nickel recovery loss reduction method in a sulfurizing step for blowing hydrogen sulfide gas into a nickel containing sulfuric acid aqueous solution to generate nickel-containing sulfides and a barren liquid, and the nickel-containing sulfides with the average particle size adjusted to a predetermined size or larger are added as seed crystals to the sulfuric acid aqueous solution. It is more preferable to adjust the average particle size of the nickel sulfides to be added as seed crystals to 55 ?m or more.

Abstract: A process for slurry hydrocracking catalyst recovery is described. In one embodiment, the process includes separating effluent from a slurry hydrocracking zone into a first portion comprising solvent and clarified pitch and a second portion comprising pitch and catalyst. The second portion is contacted with an acid to leach the catalyst out of the pitch forming an aqueous solution and pitch residue. The aqueous solution is contacted with an anion to form an insoluble salt which is the catalyst.

Abstract: A hydrogen chloride removal process includes (i) contacting in a reactor an aqueous solution, which includes one or more Fe2+-compounds, with a fluid, which includes an oxidizing agent, hydrochloric acid gas and optionally chlorine gas; and (ii) oxidizing the Fe2+-compounds to Fe3+-compounds, thereby converting the fluid to an exhaust gas, which has a reduced hydrochloric acid content.

Abstract: A method of treating value bearing material comprising oxidized or surface oxidized mineral values includes the steps of crushing the value bearing material, contacting the crushed material! with a sulfide solution to sulfide the oxidized or surface oxidized mineral values, and adding ions of a selected base metal to the crushed value bearing material. The value bearing material may comprise oxidized or surface oxidized 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: A positive electrode for a rechargeable lithium battery capable of providing a high voltage and a high voltage rechargeable lithium battery including the same, wherein the positive electrode includes a positive active material and a capacitor-reactive carbonaceous material having a specific surface area at or between 10 m2/g and 100 m2/g.

Abstract: Nickel compositions for use in manufacturing nickel metal compositions, and specifically to methods of making basic nickel carbonates used to produce nickel metal compositions are disclosed. By varying the molar ratios of carbonates and bicarbonates to nickel salts, the methods provide basic nickel carbonates that produce superior nickel-containing solids that react more effectively with phosphorous-containing ligands. The phosphorous containing ligands can be both monodentate and bidentate phosphorous-containing ligands.

Abstract: The present invention relates to a method of precipitation of metal ions. Mineral(s), oxide(s), hydroxide(s) of magnesium and/or calcium are adopted as raw materials, and the raw material(s) is processed through at least one step of calcination, slaking, or carbonization to produce aqueous solution(s) of magnesium bicarbonate and/or calcium bicarbonate, and then the solution(s) is used as precipitant(s) to deposit rare earth, such as nickel, cobalt, iron, aluminum, gallium, indium, manganese, cadmium, zirconium, hafnium, strontium, barium, copper and zinc ions. And at least one of metal carbonates, hydroxides or basic carbonates is obtained, or furthermore the obtained products are calcined to produce metal oxides. The invention takes the cheap calcium and/or magnesium minerals or their oxides, hydroxides with low purity as raw materials to instead common precipitants such as ammonium bicarbonate and sodium carbonate etc.

Abstract: Process for removing metal compounds or metalloid compounds M present in the gas phase from a gas G comprising these, wherein the gas G comprising the volatile metal compound or metalloid compound M is brought into contact with a solid donor D and the resulting reaction product is separated off.

Abstract: A method for recovering base metal values from oxide ore is provided, where the ore includes a first group metal selected from nickel, cobalt and copper. The method includes reducing ore particle size to suit the latter unit operation, favoring contact for 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 oxides from the second group, forming their respective chlorides, selectively dissolve the produced base metal chlorides, leaving the metal as oxides and in the solid state, and recovering the dissolved base metal values from aqueous solution.

Abstract: A method of synthesizing carbon-magnetite nanocomposites. In one embodiment, the method includes the steps of (a) dissolving a first amount of an alkali salt of lignosulfonate in water to form a first solution, (b) heating the first solution to a first temperature, (c) adding a second amount of iron sulfate (FeSO4) to the first solution to form a second solution, (d) heating the second solution at a second temperature for a first duration of time effective to form a third solution of iron lignosulfonate, (e) adding a third amount of 1N sodium hydroxide (NaOH) to the third solution of iron lignosulfonate to form a fourth solution with a first pH level, (f) heating the fourth solution at a third temperature for a second duration of time to form a first sample, and (g) subjecting the first sample to a microwave radiation for a third duration of time effective to form a second sample containing a plurality of carbon-magnetite nanocomposites.

Abstract: The invention relates to a method for removing arsenic as scorodite from solutions that contain iron and arsenic. In accordance with the method, arsenic is first precipitated as ferric arsenate and subsequently processed hydrothermally into crystalline scorodite.

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: The invention provides hydrometallurgical processes by which dissolved nickel may be removed from water at ambient temperature and low system pressure.

Abstract: In one aspect, the invention provides processes for producing an enriched copper concentrate from a copper-and-nickel-containing ore. Processes of the invention may include an initial step of comminuting the ore, to provide a ground ore comprising copper minerals and nickel minerals. The ground ore may be subjected to a floatation process, to separate the ground ore into distinct fractions, such as first and second concentrates. A first concentrate may for example be made up of copper-enriched-and-nickel-containing solids, while a second concentrate is made up of nickel-enriched-and-copper-containing solids. The floatation process may for example fractionate the ore so that the concentration of copper minerals is higher in the first concentrate than in the ore, and the concentration of the nickel minerals is higher in the second concentrate than the ore.

Abstract: A nickel oxide powder material that can restrain cracking of electrode due to oxidation expansion and peeling from a electrolyte and thus can decrease deterioration of the power generation characteristics, when used as an anode material for a solid oxide type fuel cell and its efficient production method, and the anode material for the solid oxide type fuel cell using the nickel oxide powder material. The nickel oxide powder material for an anode material constituting a solid oxide type fuel cell is characterized in that it is made up of a core particle (a) composed of a nickel oxide fine particle and a coating layer (b) including a zirconium hydroxide, which is formed on the surface of the core particle (a), as its main component, and that the zirconium content contained in the coating layer (b) is 0.001 to 0.01 g/m2 per surface area of the nickel oxide fine particle.

Abstract: A process for treating spent pickle liquor has the steps of mixing the spent pickle liquor with sulfuric acid, introducing oxygen into the mixture of spent pickle liquor and the sulfuric acid for a period of time, and producing diiron(II) tetrachlorosulfate from the oxygen-introduced mixture of sulfuric acid and spent pickle liquor. The spent pickle liquor and the sulfuric acid are introduced into a column. The oxygen is passed under pressure into the column. The intimate mixture of spent pickle liquor, sulfuric acid and oxygen are maintained under pressure for a period of time.

Abstract: A method of processing waste iron chloride solution including ferrous chloride, ferric chloride or mixtures thereof and optionally free hydrochloric acid, includes concentrating waste iron chloride solution into concentrated liquid having iron chloride concentration of at least 30%-40% by weight; optionally oxidizing ferrous chloride in the concentrated liquid from the concentration step to ferric chloride providing liquid containing ferric chloride; hydrolyzing the liquid containing ferric chloride from the oxidation step at 155-350° C.

Abstract: A method for recovering nickel from sulfuric acid aqueous solution, for recovering nickel in an effectively utilizable form as a raw material of nickel industry material, by separating efficiently impurity elements of iron, aluminum, manganese, etc., from the sulfuric acid aqueous solution containing nickel and cobalt, and the impurity elements, iron, aluminum, manganese, etc.

Abstract: A method for manufacturing a multiple oxide includes: a solution preparing step of adding to iron and steel pickling waste liquid, a lithium compound soluble in acidic aqueous solution and an oxoanion raw-material compound to prepare a mixed solution; a roasting step of introducing the mixed solution into a roasting furnace to roast the mixed solution; and a collecting step of collecting the multiple oxide obtained in the roasting step.

Abstract: The invention relates to a powder compound of the formula NiaMbOx(OH)y, wherein M represents Co and at least one element selected from the group consisting of Fe, Zn, Al, Sr, Mg, or Ca and mixtures thereof, or M represents Co Mn and Fe, wherein 0.6?a<1.0, 0<b?0.4, 0<x?0.60, and 1.4?y<2, wherein the powder compound has a particle size distribution d50 value, measured in accordance with ASTM B 822, of <5 ?m, and wherein a ratio of tap density, measured in accordance with ASTM B 527, to the particle size distribution d50 value is at least 0.4 g/cm3. The invention also relates to a process for preparing the compound and its uses.

Abstract: Disclosed herein is a method for the preparation of metal phosphide nanocrystals using a phosphite compound as a phosphorous precursor. More specifically, disclosed herein is a method for preparing metal phosphide nanocrystals by reacting a metal precursor with a phosphite compound in a solvent. A method is also provided for passivating a metal phosphide layer on the surface of a nanocrystal core by reacting a metal precursor with a phosphite compound in a solvent. The metal phosphide nanocrystals have uniform particle sizes and various shapes.

Abstract: A process for extracting metal values from ores or residues is disclosed. The process mentioned above is mainly suitable for aluminoferrous ores such as bauxite, titanoferrous ores such as ilmenite, or residues such as red mud waste. The process involves pulverizing the ore and/or residue and mixing with a carbonaceous material, followed by smelting the iron values and slag in the mixture to yield molten iron and oxides of aluminum and titanium. The process is simple, cost-effective, and provides effective extraction of high purity metal values.

Abstract: Processes for forming high iron content ferric chloride solutions, reconstituting ferric chloride solutions, and transporting the stable ferric chloride solutions with the high iron content are disclosed.

Abstract: A method of manufacturing an active material having a sufficient discharge capacity at a high discharge current density, an active material obtained thereby, an electrode using the same, and a lithium-ion secondary battery equipped therewith are provided. The method of manufacturing an active material comprises a step of polymerizing a mixture containing an Fe ion, an Li ion, a PO4 ion, a hydroxy acid, and a polyol, the mixture containing the polyol by a molar ratio 1.3 to 16 times that of the hydroxy acid, so as to yield a polymer; and a step of heating the polymer, so as to yield an active material containing an active material particle and carbon. The active material particle is mainly composed of LiFePO4.

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: The present invention resides in a process of recovering nickel and cobalt, regenerating the main raw materials, said process including the steps of: granulometric separation; leaching; neutralization; MHP production in only one stage and the pressure crystallization of magnesium sulphite. The process proposes a way to recovery nickel and cobalt from laterite ores through the atmospheric and heap leaching with staged addition of ore—by size separation—and H2SO4, decreasing the nickel losses and simplifying the neutralization circuit and producing a more purified MHP. The present process route is employed for nickel extraction, including the one from high magnesium containing lateritic ores.

Abstract: Provided is an arsenic-containing solid comprising 100 parts by mass of a scorodite-type iron-arsenic compound and at least 1 part by mass of an iron oxide compound added thereto, in which the scorodite-type iron-arsenic compound is produced by adding an oxidizing agent to an aqueous acidic solution that contains a 5-valent arsenic (V) ion and a 2-valent iron (II) ion, then promoting the precipitation of an iron-arsenic compound with stirring the liquid, and finishing the precipitation thereof within a range where the pH of the liquid is at most 1.2. The iron oxide compound includes goethite, hematite and their mixture, preferably having a BET specific surface area of at least 3 m2/g, more preferably at least 20 m2/g.

Abstract: A process for recovering metals from a stream rich in hydrocarbons and carbonaceous residues by means of a treatment section, characterized in that it comprises the following steps: sending said stream to a primary treatment, effected in one or more steps, wherein said stream is treated in the presence of a fluxant agent in a suitable apparatus, at a temperature ranging from 80 to 180° C., preferably from 100 to 160° C., and subjected to liquid/solid separation in order to obtain a clarified product essentially consisting of liquids and a cake (oilcake); possibly subjecting the separated cake to drying, in order to remove the hydrocarbon component having a boiling point lower than a temperature ranging from 300 to 350° C. from the cake; sending the cake, possibly dried, to a secondary thermal treatment comprising: a flameless pyrolysis of the cake effected between 400 and 800° C., preferably between 500 and 670° C.

Abstract: A process for extracting metal values from ores or residues is disclosed. The process mentioned above is mainly suitable for aluminoferrous ores such as bauxite, titanoferrous ores such as ilmenite, or residues such as red mud waste. The process involves pulverizing the ore and/or residue and mixing with a carbonaceous material, followed by smelting the iron values and slag in the mixture to yield molten iron and oxides of aluminum and titanium. The process is simple, cost-effective, and provides effective extraction of high purity metal values.

Abstract: A method of synthesizing pyrite nanocrystals is disclosed which in one embodiment includes forming a solution of iron (III) diethyl dithiophosphate and tetra-alkyl-ammonium halide in water. The solution is heated under pressure. Pyrite nanocrystal particles are then recovered from the solution.