19results about "Iron carbonyls" patented technology

The invention discloses a method for producing carbonyl iron powder and a rare earth enriched material by treating rare earth iron slag through a carbonylation method, and belongs to the technical field of metal waste recovery. Comprising the steps of pretreatment, drying, rare earth catalytic self-activation, fluidization reduction and carbonyl method selective iron separation. A metastable-state oxygen vacancy structure is constructed by means of rare earth catalytic self-activation, an efficient electron transfer channel is provided for deep reduction and carbonylation separation of iron, molecular-level dissociation of iron and rare earth is achieved in cooperation with a selective reaction of a carbonyl method, iron is converted into high-value carbonyl iron powder, meanwhile, the enrichment degree of rare earth elements is greatly increased, and the preparation method is suitable for industrial production. Original industrial solid waste is converted into a product with economic value and application potential, and the comprehensive utilization rate of resources is remarkably increased.

The application provides a surface modified carbonyl iron powder, a preparation method and application thereof. The preparation method comprises the following steps: under alkaline conditions, an oxidizing agent is introduced into a reaction system containing a sulfate and a carbonyl iron powder to perform an oxidation reaction, so that a surface modification layer is formed on the surface of the carbonyl iron powder, the surface modification layer is alpha-M x Fe y OOH, wherein x=0-1, y=0-1, M is selected from one or more of Cu, Ni, Cr, Mo, V and Nb, and the sulfate includes FeSO4 and a sulfate of M. The alpha-M x Fe y OOH (i.e. alpha-FeOOH doped with M metal) surface modification layer effectively blocks the carbonyl iron powder from contacting with chloride ions, thereby avoiding corrosion of the carbonyl iron powder. Meanwhile, FeOOH has high magnetic loss and low electric constant, thereby expanding the broadband wave absorption effect of the carbonyl iron powder.

The invention relates to the technical field of metal powder surface protection and modification, and in particular to a method for preparing a surface-coated modified carbonyl iron powder composite absorbent; the method comprises the following steps: 1) mixing carbonyl iron powder with a certain amount of surfactant aqueous solution, and mechanically stirring to obtain a carbonyl iron powder mixed solution; 2) taking a certain amount of room-temperature blackening agent and mixing the mixture evenly with water in a specific proportion, and setting the mixture aside; 3) weighing a certain amount of the carbonyl iron powder mixed solution from step 1) and the room-temperature blackening agent aqueous solution from step 2), and mechanically stirring the mixture until the reaction is complete; 4) filtering and washing the product to neutrality; and 5) vacuum drying the product at a specific temperature to obtain the carbonyl iron powder composite absorbent. The method controls the temperature resistance and wave absorbing performance of the carbonyl iron powder by adjusting the concentration of the blackening solution, the oxidation time, the type of surfactant, and the like. The process flow is simple, can be used for mass production of the composite absorbent, and is easy for industrial production and application.

The application discloses a preparation method of a composite wave-absorbing material, the composite wave-absorbing material and communication equipment. The preparation method comprises the following steps: performing copper plating treatment on graphene oxide to obtain copper-plated graphene oxide; and performing composite treatment on the copper-plated graphene oxide and carbonyl iron powder to obtain the composite wave-absorbing material.

The invention discloses a preparation method of carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, which comprises the following specific steps: weighing ferrite synthetic components, spherical carbonyl iron powder and tetraethoxysilane according to a ratio, the ferrite synthetic components comprise 52-56 mol% of Fe2O3 and the balance of CoO, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder. The carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is finally obtained through the steps of ball milling, stirring, drying, primary sintering, mixing, secondary sintering and the like. The method for preparing the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is simple and convenient in process, safe and low in cost, and after the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is used for preparing wave-absorbing products, the excellent performance of broadband strong absorption is shown in the frequency band of 2-18 GHz.

The invention discloses a carbonyl iron / silane modified graphene oxide composite wave-absorbing material and preparation thereof, and belongs to the technical field of wave-absorbing materials. Silane modified graphene oxide and carbonyl iron powder are compounded to prepare the wave-absorbing material with the core-shell structure, and the wave-absorbing material comprises carbonyl iron and silane modified graphene oxide compounded on the surface of the carbonyl iron. Silane is used for carrying out surface modification on graphene oxide, and the dielectric constant of the composite wave-absorbing material is better matched with the wave impedance of a free space by regulating and controlling the dosage of silane and graphene oxide in the silane modification process and adjusting the ratio of silane modified graphene oxide to carbonyl iron when the composite material is prepared; the ratio of the magnetic conductivity to the dielectric constant is optimized, and the overall wave-absorbing strength of the composite material is improved.

This invention provides a method for improving the reaction rate of nickel carbonyl synthesis, belonging to the field of carbonyl metallurgical technology. It solves the problems of low gas-solid reaction efficiency and dust blockage in existing nickel carbonyl synthesis reactions. This invention purifies CO, controlling the N2 content in the CO gas participating in the nickel carbonyl synthesis reaction to below 0.3%. The CO not participating in the carbonyl synthesis reaction and the CO obtained from the decomposition reaction of nickel carbonyl are pressurized and enter an adsorption tower for adsorption, pressure equalization, displacement, reverse release, and evacuation. Then, a vacuum pump extracts the adsorbed CO from the copper-loaded adsorbent to a CO gas holder for storage. A gas switching device is installed at the CO inlet of the synthesis reactor, ensuring that CO gas always enters from the bottom of the reactor and slowly passes through the material layer from bottom to top. This invention improves the reaction rate of nickel carbonyl synthesis by controlling the N2 content in the CO gas during the nickel carbonyl synthesis reaction and optimizing the solution to the problems of low gas-solid reaction efficiency and dust blockage.

This invention discloses a method for treating rare earth iron slag using carbonylation to produce carbonyl iron powder and rare earth enriched materials, belonging to the field of metal waste recycling technology. The method includes pretreatment, drying, rare earth catalytic self-activation, fluidized bed reduction, and selective separation of iron via carbonylation. This invention utilizes rare earth catalytic self-activation to construct a metastable oxygen vacancy structure, providing an efficient electron transfer channel for the deep reduction and carbonylation separation of iron. Combined with the selective reaction of the carbonylation method, it achieves molecular-level dissociation of iron and rare earth elements, converting iron into high-value carbonyl iron powder while significantly increasing the enrichment of rare earth elements. This transforms industrial solid waste into a product with both economic value and application potential, significantly improving the comprehensive utilization rate of resources.

The invention relates to heteroatom-oxide co-doped carbon layer coated flaky carbonyl iron as well as a preparation method and an application method thereof, and the preparation method comprises the following steps: carrying out wet mechanical ball milling on spherical carbonyl iron to obtain flaky carbonyl iron powder; secondly, plant polyphenol, ethidene diamine and ferric iron salt are mixed and then added into the flaky carbonyl iron, the plant polyphenol is oxidized into benzoquinone molecules, the benzoquinone molecules and ethidene diamine are subjected to Michael addition and rearrangement to form a cross-linked polymer, and the cross-linked polymer is coated on the surface of the flaky carbonyl iron powder; and finally, the modified flaky carbonyl iron is placed in a tubular furnace to be subjected to high-temperature treatment, and the heteroatom-oxide co-doped carbon layer coated flaky carbonyl iron with the electromagnetic synergistic loss is obtained. The preparation method is simple, and the material has excellent electromagnetic wave absorption capacity and has wide application prospects in the fields of daily protection, flight equipment stealth and the like.

The invention provides a method for enriching rare earth based on neodymium iron boron waste, and belongs to the technical field of magnetic materials, the method comprises the following steps: oxidizing roasting and crushing the neodymium iron boron waste to obtain neodymium iron boron powder, and the oxidizing roasting process comprises the following steps: keeping the temperature at 300-500 DEG C for 1.0-2.0 hours, and then keeping the temperature at 600-900 DEG C for 2.0-3.5 hours; the neodymium iron boron powder is granulated, a pressing technology is not adopted in the granulating process, and the particle size ranges from 100 micrometers to 500 micrometers; the granulated material is reduced, and ferric oxide is reduced into iron elementary substance; and carrying out carbonyl synthesis on the reduced material to generate pentacarbonyl iron liquid and obtain a rare earth enriched material at the same time. According to the method, on the basis of not adding an activating agent, the extraction rate of iron is 93% or above, and rare earth elements in the synthetic residues are enriched to 85% or above.

The invention relates to a graphene-based carbonyl iron powder doped nano titanium dioxide composite material and a preparation method thereof, the composite material comprises the following raw materials: graphene oxide, carbonyl iron powder and nano titanium dioxide, the mass ratio of graphene oxide to carbonyl iron powder is 1: (0.5-1.5), and the molar ratio of carbonyl iron powder to nano titanium dioxide is 1: (1-3); the graphene oxide, the carbonyl iron powder and the nano titanium dioxide are mutually combined through a spray drying method; the scheme provided by the invention has the advantages that the impedance matching performance of the graphene-based material is improved, the graphene-based material has a relatively high reflection loss rate and a relatively wide effective absorption bandwidth when the graphene-based material has a relatively low filling rate, the processing of the composite material is facilitated, and the cost is reduced.

Methods and reactor systems are provided for extracting metals, such as nickel, cobalt, and iron, from reduced, activated metal compounds (“feed materials”). Feed materials may be derived from mixed hydroxide precipitate. Feed materials and carbon monoxide gas are delivered into an extraction reactor of a reactor system, such as a shell tube heat exchanger. A flow path therein directs the feed material downward and the carbon monoxide gas upward, enabling contact therebetween, forming at least one metal carbonyl gas and a solid residue therein. The flow path further directs the upward flow of metal carbonyl gases, and the downward flow of the residue. Methods and reactor systems may further purge the residue: using nitric oxide to convert any remaining dicobalt octacarbonyl therein to cobalt tricarbonyl nitrosyl gas; using an inert gas to removing any cobalt tricarbonyl nitrosyl therein; and using an inert gas-oxygen mixture, to form a passivated residue.

The invention belongs to the technical field of soft magnetic materials, and discloses a method for efficiently reducing and purifying carbonyl iron powder. The method comprises the following steps: S1, coating the surface of carbonyl iron powder to be purified with a silicon dioxide prefabricated layer by adopting a sol-gel method; the silicon dioxide prefabricated layer contains occupied particles; s2, removing occupying particles in the silicon dioxide prefabricated layer to obtain a silicon dioxide protective layer; a hole structure is distributed in the silicon dioxide protection layer; and S3, the carbonyl iron powder treated in the step S2 is reduced under reducing gas, and purified carbonyl iron powder is obtained. According to the method, the silicon dioxide protection layer distributed with a large number of penetrating holes is provided to ensure that the temperature of reducing and purifying the carbonyl iron powder is increased to 750 DEG C without the problems of caking, agglomeration and the like, so that the rapidness and high efficiency of the reducing and purifying process of the carbonyl iron powder are realized to the greatest extent; and the method has the advantages of simple process, low cost, mass production and the like.

The invention discloses a flaky carbonyl iron powder wave-absorbing agent with a porous double-shell structure and a preparation method of the flaky carbonyl iron powder wave-absorbing agent. The method comprises the following steps: preparing flaky carbonyl iron powder (FCIP) by adopting a mechanical ball milling method, and then constructing a porous shell structure on the surface of the FCIP, the shell structure comprises two layers, the first layer is a porous carbon material, and the second layer is a porous oxide. According to the preparation method of the carbonyl iron powder core-shell structure with the porous shell layer, through the design of the porous shell layer structure, the impedance matching performance is enhanced, meanwhile, the wave absorbing capacity of the carbonyl iron powder is improved through shell layer components, and the carbonyl iron powder core-shell structure has important application prospects in the field of electromagnetic absorption.

The invention provides corrosion-resistant and high-temperature-resistant flaky carbonyl iron powder coated with polyurethane urea as well as a preparation method and application of the corrosion-resistant and high-temperature-resistant flaky carbonyl iron powder. The method comprises the following steps: step 1, adding an HCL solution into flaky carbonyl iron powder, and stirring; step 2, continuously adding absolute ethyl alcohol, dropwise adding a silane coupling agent, and carrying out ultrasonic treatment; 3, deionized water and acetone are evenly mixed, the mixture is added into the solution obtained in the step 2 for ultrasonic treatment, then polyether glycol, isophorone diisocyanate and N, N-bis (2-ethoxyl) amino methylene dimethyl phosphonate are added, water bath heating is conducted, and stirring is conducted; 4, continuously adding N-[3-(trimethoxysilyl) propyl] ethylenediamine, heating in a water bath, and stirring; and step 5, then carrying out solid-liquid separation, washing and drying. The corrosion-resistant and high-temperature-resistant flaky carbonyl iron powder coated with polyurethane urea, prepared by the preparation method disclosed by the invention, not only has good corrosion resistance and high-temperature resistance, but also has relatively good wave-absorbing performance at a low-frequency band.

The invention belongs to the technical field of preparation of metal organic compounds, and particularly relates to a preparation method and device of carbonyl iron. The preparation method comprises the following steps: S1, introducing iron powder and carbon monoxide into a reaction device, and carrying out catalytic reaction under the action of a catalyst to generate crude carbonyl iron; s2, cooling the crude carbonyl iron to obtain liquid carbonyl iron; s3, carrying out reduced pressure distillation on the cooled liquid carbonyl iron; and S4, purifying the liquid carbonyl iron after reduced pressure distillation to obtain the final product carbonyl iron. The preparation device comprises a storage tank, a purifier, a reaction kettle, a condenser, a reduced pressure distillation tower and a recrystallization device which are sequentially arranged along the material flow direction. The method provided by the invention can obviously improve the reaction rate of carbonyl iron, improve the product purity and reduce the safety risk.

The present disclosure provides a method for purifying nanostructured material comprising carbon nanotubes, metal impurities and amorphous carbon impurities. The method generally includes oxidizing the unpurified nanostructured material to remove the amorphous carbon and thereby exposing the metal impurities and subsequently contacting the nanostructured material with carbon monoxide to volatilize the metal impurities and thereby substantially remove them from the nanostructured material.

This invention relates to an electromagnetic wave absorbing material in the 600MHz-1GHz frequency band, its preparation method, and its applications. The electromagnetic wave absorbing material comprises a magnetic composite material and carbonyl iron particles, wherein the carbonyl iron particles are aggregates of multiple two-dimensional nano-carbonyl iron particles. The magnetic composite material comprises carbon crystal clusters composed of multiple carbon crystals and tungsten disulfide. At least a portion of the carbon crystals have tungsten disulfide and carbonyl iron particles attached to their surfaces, and at least a portion of the interstices between the carbon crystal clusters are filled with tungsten disulfide and carbonyl iron particles. The carbon crystals are three-dimensional prismatic in shape and have a porous structure, while the tungsten disulfide is plate-like. This electromagnetic wave absorbing material has the advantages of being lightweight and having good thermal stability, and exhibits strong absorption performance for electromagnetic waves in the 600MHz-1GHz frequency band.

The invention relates to the field of preparation of wave-absorbing materials, in particular to a preparation method of a novel corrosion-resistant iron-based microwave wave-absorbing material. The preparation method comprises the following three steps: S1, preparation of fluorinated graphene; S2, preparation of flaky carbonyl iron powder; and S3, composite preparation. In the step S1, no acidic substance is used, but sodium cholate is added, so that the problem that fluorinated graphene is agglomerated and settled in water is effectively solved, and the stripped fluorinated graphene can be stably dispersed in an aqueous solution in a single-layer or few-layer state. According to the preparation method, hazardous chemical reagents such as acid are not introduced, and the product is high in quality, complete in structure, more environmentally friendly, safer, low in equipment requirement, few in product defect and easy to produce on a large scale. The composite wave-absorbing material prepared by the method provided by the invention still maintains relatively high magnetic conductivity at high frequency, and breaks through the snoek limit.