333 results about "Iron(III) oxide" patented technology

The invention discloses a method for recovering lithium, nickel cobalt manganese composite hydroxide and aluminum copper powder from a waste ternary lithium ion battery pole piece. The method comprises the following steps: treating waste pole pieces of a ternary plant or a mixture of positive and negative pole pieces by using a Fenton technology, leaching by using a mixed ferric salt solution, and filtering to obtain lithium-containing leachate and slag; adjusting the pH value of the leachate, oxidizing and filtering to obtain a purified solution and ferric hydroxide precipitate, and adding the purified solution and a lithium hydroxide solution into a reactor for coprecipitation to obtain a deeply purified solution and the nickel-cobalt-manganese composite hydroxide. And dissolving the ferric hydroxide precipitate with dilute acid, adding a reducing agent to generate a ferrous salt solution, and returning the ferrous salt solution for Fenton reaction and leaching reaction. And adding the sodium carbonate saturated solution into the deep purification solution, and crystallizing and precipitating to obtain the battery-grade lithium carbonate. And performing hydrodynamic screening on the leaching residues to obtain an aluminum-copper mixture and graphite residues, and performing grinding and specific gravity separation on the aluminum-copper mixture to obtain high-purity aluminum powder and copper powder. According to the method, the iron salt is directly leached from the pole piece, the used iron salt can be recycled, and the method is suitable for large-scale recovery of the waste ternary lithium ion battery.

The invention discloses a metal soft magnetic powder core and a preparation method thereof.The preparation method comprises the steps that cold sintering is conducted, under the ultrasonic-assisted condition, warm-pressing is conducted on mixed powder containing modified iron powder and a release agent, and a metal soft magnetic powder core green body is obtained; wherein the modified iron powder comprises iron powder and a coating layer, the surface of the iron powder is coated with the coating layer, and the coating layer comprises copper, hydrated ferric oxalate, hydrated cupric oxalate and iron oxide; and heat treatment is conducted, specifically, the metal soft magnetic powder core green body is subjected to heat treatment under the oxygen-containing condition, and the metal soft magnetic powder core is obtained. Ultrasonic assistance is introduced when the modified iron powder is subjected to cold sintering, and a mixed insulation coating layer of ferric oxide and copper oxide can be generated on the surfaces of powder particles in situ during heat treatment, so that the compactness, the strength, the resistivity and the magnetic conductivity of the magnetic core are improved while the pressing force is reduced and the pressing efficiency is improved.

The invention provides a production process for stably controlling adhesive force of a DP steel zinc layer. The production process comprises the following steps: step 1, setting a heating section 1, a heating section 2 and a furnace nose section in a total radiation heating annealing furnace; 2, according to the model and thickness of DP steel, target dew points of a first heating section, a second heating section and a furnace nose section are set; 3, according to the target dew points set in the first heating section, the second heating section and the furnace nose section in the step 2, water vapor is put into the protective gas for humidification, and the water vapor reacts with Si, Mn and Cr elements enriched on the surface of the steel plate to generate volatile oxides; the dew point of the annealing furnace is precisely controlled in a segmented mode, different humidification modes are adopted, and the surface state is controlled, so that surface oxide residues are reduced, cleanliness of a steel substrate is guaranteed, and the binding force of a zinc layer is improved; the iron oxide layer formed on the surface of the steel plate enters a reducing atmosphere annealing furnace containing hydrogen, the hydrogen can reduce the iron oxide layer on the surface of the steel plate to form a reduced iron layer, and the adhesive force of a zinc layer is improved.

The invention relates to the technical field of iron ore tailing resource utilization, in particular to a method for preparing iron oxide yellow by leaching iron ore tailings through an advanced oxidation technology, which comprises the following steps: adding a required amount of iron ore tailing powder into a persulfate solution, stirring to react, adding a reducing agent, boiling, filtering, adding alkali liquor to adjust the pH value, and filtering, thereby obtaining the iron oxide yellow. Pure liquid containing ferrous ions is obtained; taking part of the pure solution containing ferrous ions, and adding a potassium hydroxide solution to obtain an iron oxide yellow seed crystal solution; adding a pure solution containing ferrous ions into the iron oxide yellow seed crystal solution, adding an alkali solution to adjust the pH value, reacting, and separating and drying a product to obtain the iron oxide yellow. According to the method, the persulfate is adopted to leach iron from the iron ore tailings, and the iron oxide yellow is prepared from the leachate; harmless treatment of the iron ore tailings and value-added utilization of valuable resources are achieved, the raw material source of the iron oxide yellow industry is widened, and a wider prospect is provided for development of iron oxide yellow.

The invention belongs to the technical field of environmental rock soil, and particularly relates to a preparation method of zeolite-magnetic iron oxide and application of the zeolite-magnetic iron oxide in catalyzing sodium percarbonate to repair petroleum hydrocarbon polluted soil. The specific method comprises the following steps: carrying out alkali treatment on zeolite, and then carrying out heat treatment to obtain alkali-heat combined modified zeolite; extracting an iron element in the iron-containing by-product with acid and preparing ferric hydroxide colloid; and uniformly mixing the alkali-heat combined modified zeolite with the ferric hydroxide colloid, carrying out solid-liquid separation, and then carrying out heat treatment and hydrogen reduction treatment to obtain the zeolite-magnetic iron oxide, the application specifically comprises the following steps: uniformly mixing sodium percarbonate, tween-80, silica sol and water to prepare a turbid solution A; uniformly mixing zeolite-magnetic iron oxide, organic acid, silica sol and water to prepare a turbid solution B; and uniformly mixing the turbid liquid B with the petroleum hydrocarbon polluted soil, then adding the turbid liquid A, uniformly mixing, and maintaining for 12-15 days to finish the remediation.

The invention discloses a method for improving corrosion resistance of steel, and belongs to the technical field of metal protection. The method for improving the corrosion resistance of the steel comprises the following procedures of acid pickling, rinsing, drying, reduction, hot dipping, passivation, drying and packaging. Replacing a plating assisting process in the hot dipping process with a thermal reduction process; and in the thermal reduction process, hydrogen with the volume content of 3-25% is adopted for thermal reduction. A plating assisting technology in a traditional hot dipping technology is replaced with a reduction technology, the steel obtained after acid pickling is dried and then fed into the atmosphere box, a small amount of iron oxide remaining on the surface of the steel is reduced into sponge iron in the hydrogen reduction atmosphere, the surface of the steel keeps active, and then a zinc-based or zinc alloy plating layer can be better plated; therefore, the corrosion resistance of the steel is greatly improved, and the service life is prolonged.

The invention relates to the technical field of preparation of a lithium ion battery negative electrode material, in particular to a metal organic framework coating for improving the performance of an iron oxide negative electrode lithium ion battery and a preparation method of the metal organic framework coating. The metal organic framework coating mainly comprises the step of coating the iron oxide by growing a metal organic framework on the surface of the iron oxide in situ. According to the invention, in-situ synthesis of a metal organic framework material on the surface of iron oxide is innovatively proposed, and the iron oxide material is coated in a hollow structure through a structure provided by an organic framework, so that volume expansion and shrinkage of iron oxide in charge and discharge processes are effectively buffered. By regulating and controlling the mass ratio of the organic framework to the ferric oxide, the high-rate discharge performance and the specific discharge capacity of the ferric oxide negative electrode are improved.

The invention relates to the technical field of fire coal additives, in particular to a high-efficiency coal saving agent and a preparation method thereof. The coal saving agent is prepared from the following raw materials in percentage by mass: 7-14% of an oxygen supply agent, 5-12% of a combustion improver, 5-13% of a catalyst, 0.1-1% of industrial waste residues, 1-3% of a desulfurization additive, 1-2% of a dispersing agent and the balance of deionized water, wherein the catalyst is a Ce-Mn / TiO2 catalyst, and the catalyst is a TiO2 catalyst; the industrial waste slag is selected from at least one of cold-rolled iron oxide slag, nickel slag or steel slag; the desulfurization additive is selected from at least one of calcium acetate, calcium oxide or calcium carbonate. The coal-saving agent can effectively improve the combustion characteristic of coal, improve the combustion efficiency and the combustion effect, and realize the efficient coal-saving effect under the condition of low mixing amount; meanwhile, desulfurization and denitrification can be achieved, emission of sulfide and nitric oxide is reduced, and environmental pollution can be prevented and controlled.

The invention relates to the technical field of ceramics, in particular to mottle crack glazed ceramic and a preparation method thereof.The ceramic comprises a green body, ground glaze and cover glaze, and the ground glaze is prepared from, by weight, 30-35 parts of kaolin, 25-30 parts of quartz, 20-25 parts of feldspar, 8-12 parts of ferric oxide, 5-8 parts of calcium carbonate and 3-5 parts of borax; the cover glaze is prepared from the following raw materials in parts by weight: 35 to 40 parts of feldspar, 25 to 30 parts of quartz, 6 to 10 parts of copper oxide, 5 to 8 parts of granular rock powder, 8 to 12 parts of borax and 5 to 8 parts of clay. Embedding porous particles into the green body to initiate explosion cracks, and fusing interlayer stress cracks and devitrification cracks to form a multi-stage composite crack network; iron ions in the ground glaze and copper ions in the cover glaze form ion gradient migration through the iron axe stone powder in the middle layer to generate red and green blended stripes; the microcapsule carbon powder regulates and controls the pores and texture of the glaze, and copper foil fragments are oxidized and reduced to form gilding-brown mottles.

The invention provides coal gangue-based artificial soil as well as a preparation method and application thereof. The preparation method of the coal gangue-based artificial soil comprises the following steps: S1, modifying coal gangue by adopting a solution containing citric acid and ethylenediamine tetraacetic acid to obtain modified coal gangue; s2, preparing the modified coal gangue into artificial soil. According to the invention, the citric acid can dissolve carbonate in the coal gangue, the released carbonate can be combined with heavy metals, and citrate ions and ferric ions can form a complex to destroy the outer layer of ferric oxide of the heavy metals; ethylenediamine tetraacetic acid can permeate into mineral lattices of the coal gangue, lattice bound state heavy metal is released through octahedral Al-O bond breakage, the ethylenediamine tetraacetic acid can capture heavy metal combined with citric acid, a more stable heavy metal complex is formed, the heavy metal complex carries strong negative charges, and the heavy metal complex can be separated from the coal gangue. And electrostatic repulsion can be generated on the surface of the coal gangue with negative electricity, so that the heavy metal removal effect is improved.

The invention discloses an iron oxide-iron cluster catalyst for a reverse water gas shift reaction and preparation of the iron oxide-iron cluster catalyst. The catalyst is a double-site material Fe2O3-Fe4 / C of carbon-loaded iron oxide particles and iron clusters. The preparation method comprises the following steps: firstly, synthesizing an NH2-MIL-88B (Fe) material through a solvothermal method, then grinding and uniformly mixing the NH2-MIL-88B (Fe) material with KCl, feeding the mixture into a tubular furnace for high-temperature calcination, and washing after cooling to obtain the MOFs-derived double-site catalyst, namely Fe2O3-Fe4 / C. The MOFs-derived Fe2O3-Fe4 / C double-site catalyst prepared by the invention is low in cost and simple and convenient in process, and when the MOFs-derived Fe2O3-Fe4 / C double-site catalyst is applied to a low-temperature catalytic reverse water-gas shift reaction, the CO2 conversion rate and the CO space-time yield are greatly improved, and the industrial application potential is huge.

According to the red mud-based composite material and the preparation method and application thereof, bentonite, red mud and biomass are mixed in a proper amount of water according to the mass ratio of 1: 1: (1-10), and first suspension liquid is formed; drying the first suspension to obtain a precursor of the red mud-based composite material; the precursor is subjected to a carbon thermal reaction at 300-700 DEG C, ferric oxide in the red mud is converted into zero-valent iron, and the red mud-based composite material is obtained. The red mud is alkaline and promotes manganese ions to form insoluble precipitates, the unique structure and ion exchange capacity of the bentonite can effectively solidify the manganese ions, the biomass has a high specific surface area and a developed pore structure, and the manganese ions are physically adsorbed through Van der Waals' force and pore interception; ferric oxide in the red mud is converted into zero-valent iron in the carbothermal reaction process, and the zero-valent iron can catalytically oxidize ammonia nitrogen, so that the red mud-based composite material synchronously solves the problem of combined pollution of manganese and ammonia nitrogen in the soil.

The invention provides a coal-based solid waste foamed cement material for filling a coal mine tunnel and a preparation method of the coal-based solid waste foamed cement material. The coal-based solid waste foamed cement material comprises 10-30 parts of coal gasification coarse slag micro powder, 0-30 parts of first-grade fly ash, 70-90 parts of cement, 0.3-0.8 part of a foam stabilizer and 0.1-0.5 part of an additive, the coal-based solid waste foamed cement material is further doped with foam, the mixing amount of the foam is 2-5 times of the volume of the cement slurry, the coal gasification coarse slag micro powder is coal water slurry furnace gasification coarse slag, and the coal gasification coarse slag micro powder is prepared from, by mass, 40% of silicon dioxide, 19% of aluminum oxide, 15% of ferric oxide, 16% of calcium oxide, 3% of sulfur trioxide, 3% of sodium oxide, 1% of magnesium oxide and 0.5% of titanium oxide. And 0.5% of potassium oxide. According to the invention, a physical foaming method is utilized, coal-based solid waste is used as a raw material to replace part of cement, and the foamed cement material with light weight and high strength is prepared, so that the foamed cement material meets the use requirements of underground roadway filling.

Separating the specific gravity gt of the solid-liquid mixture type underflow red mud discharged in aluminum oxide production from liquid; continuously grading and separating out ferric oxide, trace heavy metal minerals and rare earth from the 5 g / cm < 3 > material, and carrying out solid-liquid separation treatment; the separated materials with the specific gravity smaller than or equal to 5 g / cm < 3 > are atomized and dispersed into particles and liquid drops, the particles and the liquid drops are quickly freeze-dried to prepare fine particles, and the fine particles are divided into sodium aluminosilicate and silicon oxide mixed particles, calcium compound mixed particles and crystallized sodium hydroxide, sodium aluminate and ice crystal particles through multi-stage specific gravity classification in the environment with the temperature smaller than-5 DEG C; and sublimating and dehydrating the separated sodium aluminosilicate and silicon oxide mixed particles and calcium compound mixed particles to form powder materials, and melting sodium hydroxide, sodium aluminate and ice crystal particles at normal temperature to form a solution containing sodium aluminate and sodium hydroxide.

The invention provides a high-added-value recycling method of silicon and iron elements in iron tailings, and relates to the technical field of high-value and resource utilization of metallurgical solid wastes. The method comprises the steps of iron tailing grinding, middle-stage magnetic separation, microwave roasting, water quenching, grinding, high-stage magnetic separation, first-stage hot-pressing acid leaching, vacuum roasting, water quenching, second-stage hot-pressing acid leaching, low-stage magnetic separation of weakly magnetic minerals, ultrasonic acid leaching for iron extraction, aging reaction, filtering, drying and roasting. And finally obtaining high-purity quartz powder of more than 4N grade and nano iron oxide of which the purity of Fe2O3 is more than 95%. According to the method, silicon and iron elements in the iron tailings are recycled in a layered and stepped manner, and the acid leaching filtrate generated in the preparation process of the high-purity quartz powder is subjected to closed treatment, so that valuable components of silicon and iron in the iron tailings are utilized at a high value to the maximum extent, and no secondary waste liquid is discharged; meanwhile, the problem of fluorine pollution in the traditional process is avoided in the process of preparing the high-purity quartz powder, and the method is low-carbon and green and has remarkable economic benefits.

The invention relates to a process for preparing pure iron by using red mud, which is characterized in that the red mud is Bayer process red mud, i.e., solid waste residue formed by solid-liquid separation after aluminum oxide is dissolved out from bauxite through high temperature, high pressure and strong alkali in the process of producing aluminum oxide by adopting a Bayer process, so that the environmental burden caused by the Bayer process red mud can be solved; the method is beneficial for reducing carbon emission in the aspect of iron element extraction and promoting development of a green metallurgical technology, and is characterized by comprising the following steps: taking Bayer process red mud as a raw material, carrying out acid leaching on the Bayer process red mud to obtain a ferrous oxalate extract, calcining the ferrous oxalate to obtain iron oxide, and recycling the iron oxide. And dissolving the ferric oxide into a sulfuric acid solution to obtain a ferric sulfate solution, taking the ferric sulfate solution as an electrolyte in an electrolysis device, and obtaining electrolytic iron through the electrolysis device, so that the pure iron is prepared from the red mud.

The invention belongs to the technical field of iron oxide preparation, and discloses a method for purifying iron oxide for soft magnetic ferrite from red mud and application of the method. The red mud is subjected to crushing and wet grinding, and red mud slurry is obtained; the red mud slurry is subjected to magnetic separation, drying and grinding into powder, and a magnetic product containing ferric oxide is obtained; the magnetic product is subjected to acid leaching and suction filtration with hydrochloric acid, and first filtrate is obtained; carrying out alkaline leaching treatment on the first filtrate by adopting sodium hydroxide, filtering and drying to obtain a red brown dry material; grinding the red brown dry material into powder, washing with deionized water, carrying out suction filtration, and drying to obtain a first dry material; and grinding the first dry material to a powder state, and carrying out aerobic sintering to obtain the reddish brown solid iron oxide. The iron oxide extracted through the method can replace existing high-purity commercial iron oxide and can be applied to preparation and development of soft magnetic materials, and various properties of the soft magnetic materials are indifferent or even higher.

The invention provides a collaborative recovery method for directionally converting SO2 into waste tire cord steel wires, and belongs to the technical field of solid waste recycling. According to the collaborative recovery method provided by the invention, the granular waste tire cord steel is roasted in an SO2 / O2 / N2 mixed atmosphere and an air atmosphere in sequence, and then the valuable metal components copper, zinc and iron in the waste tire cord steel wire are directionally converted into copper sulfate, zinc sulfate and iron oxide through further leaching and magnetic separation processes. According to the method, efficient recovery and resource utilization of valuable metal components of copper, zinc and iron in the waste tire cord steel wires are achieved, an innovative solution is provided for high-value utilization of the waste tire cord steel wires, and the method has good application prospects and social and ecological benefits.

The invention relates to the technical field of steel for agricultural machinery, in particular to a manufacturing method of a surface hardening agricultural machinery tool. Comprising the steps of smelting, continuous casting, casting blank treatment, rolling, cooling, surface treatment, part forming, heat treatment and local surface hardening treatment. The obtained hot-rolled plate is free of surface scale, the hardness after heat treatment is 53 HRC or above, the surface hardness difference is + / -0.5 HRC, the tensile strength is 1800 MPa or above, the ductility is larger than or equal to 8%, the ballistic work Akv at the temperature of 20 DEG C is larger than or equal to 20 J, tempering treatment, sand blasting and tumbling are not needed, the hardness of an agricultural machine tool obtained after surface local hardening treatment is 60 HRC or above, and the wear resistance is obviously improved.

At least one embodiment of the invention provides a preparation method of sponge titanium, which comprises the following steps: pretreating bauxite tailings to obtain a first mixture; carrying out acid treatment on the first mixture, and filtering to obtain a second mixture; putting the second mixture into a reaction kettle containing an alkaline substance to react so as to convert the ferric titanate into titanate and ferric oxide or ferrous hydroxide to obtain a third mixture; carrying out suction filtration treatment on the third mixture to obtain a first solid phase and a first liquid phase, and drying and grinding the first solid phase; roasting the dried and ground first solid phase to form an iron elementary substance, and carrying out magnetic separation to remove the iron elementary substance; adding an acidic material into the first liquid phase for reaction to obtain metatitanic acid colloid, and washing the metatitanic acid colloid; the metatitanic acid colloid is subjected to calcination, chlorination reaction and replacement reaction in sequence to obtain the sponge titanium. The sponge titanium obtained through the preparation method is high in purity.

The invention discloses a method for detecting the content of iron oxide impurities in brown aluminum oxide. The method comprises the following steps: sampling; preparing a sample solution; obtaining the volume of the sodium thiosulfate solution consumed by the sample solution; obtaining the volume of the sodium thiosulfate solution consumed by the purified water; and determining the percentage content of the iron oxide impurity in the brown aluminum oxide. According to the method for detecting the content of the iron oxide impurity in the brown aluminum oxide, the content of the impurity ferric oxide in the brown aluminum oxide can be simply and quickly detected at very low cost under the conditions that expensive instruments are not used and tedious and complicated operation steps are not needed.

The application discloses a kind of iron oxide / nickel ferrite composite nanorods and synthesis method thereof, belong to nanometer material technical field.The obtained composite nanorod is polycrystalline structure, and is composed of rhombohedral Fe2O3 and cubic NiFe2O4 crystal phase.The diameter of the composite nanorod is 10-100nm, and the length is greater than 500nm.The synthesis method is that iron acetate and nickel acetate are dissolved in deionized water, heated to temperature 80-100 DEG C, and kept for 1-5h, and iron oxide / nickel ferrite precursor is obtained after cooling and drying;iron oxide / nickel ferrite precursor is mixed with calcium chloride and sodium chloride, then the mixture is loaded into corundum crucible, the crucible is placed in reaction furnace, at temperature 800-1000 DEG C, and kept for 5-10h.The synthesis process of the application is simple, does not need complex equipment, and is easy to control.Iron oxide / nickel ferrite composite nanorod has a large number of catalytic active sites, and is expected to have good interface performance, catalytic activity, electrical and magnetic properties, and has good application prospect in catalysts, electrical devices and magnetic devices.

The invention provides a method and system for detecting the corrosion degree of a wire steel core of an overhead transmission line, and the method comprises the steps: carrying out the multi-angle X-ray transmission of a whole to-be-detected wire in an electrified state, and obtaining a projection sequence; inverting the projection sequence into a steel core three-dimensional density body, segmenting and identifying the steel core, the air and the corrosion area based on the steel core three-dimensional density body, and calculating the corrosion sectional area loss rate of the steel core; the chemical state of the Fe element is obtained in the corrosion area, satellite peaks of Fe-K alpha and iron oxide are collected respectively, and the concentration ratio of Fe < 0 > to Fe < 3 + > is calculated; according to the steel core corrosion sectional area loss rate and the concentration ratio of Fe < 0 > to Fe < 3 + >, the corresponding corrosion grade and residual strength of the wire to be detected are output, and the problems that in the prior art, the detection efficiency and reliability of the steel core corrosion degree of the wire of the overhead transmission line are not high are effectively solved. And the detection efficiency and reliability of the corrosion degree of the wire steel core of the overhead transmission line are effectively improved.

The utility model relates to the technical field of screening equipment, in particular to a screening device for iron oxide, which comprises a box body, a stepping motor is arranged at the top end of the box body, the stepping motor is connected with a roller through a rotating structure, a barrier strip rotating clockwise is arranged on the inner wall of the roller, and the barrier strip is connected with the box body. The outer wall of the roller is provided with screening holes which can allow iron oxide powder to pass through and are evenly distributed, the bottom end of the box body is provided with a discharging port, and a collecting box capable of collecting the powder is arranged below the discharging port. According to the iron oxide screening device, iron oxide placed in the roller can be driven by the barrier strip to be turned over and beaten in the roller through the barrier strip and the screening holes, so that the iron oxide can be always in a movable state through the rotary turning of the roller, the blocking condition is not easy to occur, and even if blocking occurs, the iron oxide can be cleaned through flushing water; and the screening efficiency is greatly improved.

This invention relates to the field of iron and steel metallurgy and proposes a method for controlling the corrosion-resistant iron oxide scale on the surface of hot-rolled steel plates. The method includes the following steps: First, molten steel is smelted and cast into steel billets; then, the steel billets are heated to 550-600℃ and held at an air-fuel ratio of 1.1-1.3 for 20-30 minutes; subsequently, the temperature is raised to 1100-1150℃ and held at an air-fuel ratio of 1.0-1.1 for 40-60 minutes; finally, the temperature is raised to 1180-1220℃ and held at an air-fuel ratio of 0.9-1.0 for 20-30 minutes to obtain the heated steel billet; the heated steel billet is then hot-rolled and cooled to obtain the steel plate. This technical solution solves the problems of uneven iron oxide scale growth and poor adhesion to the matrix in related technologies.

The application discloses a production method for controlling the thickness of iron oxide scale of free-cutting steel, and the process steps are as follows: hot metal pretreatment, converter steelmaking, CAS treatment, LF furnace external refining, continuous casting, heating furnace heating, rolling, controlled cooling, coil collecting and finished product inspection. The composition and thickness of the surface iron oxide scale of the free-cuting steel wire rod are controlled by controlling the wire drawing temperature and the post-rolling cooling speed, the wire drawing temperature is ensured to be below 860 DEG C by adjusting the water amount of the water tank after the finishing mill, the Fe2O3 red rust is generated on the surface of the wire rod, and the proportion of Fe3O4 in the iron oxide scale on the surface of the wire rod is prevented from being increased due to the excessively high wire drawing temperature. The wire drawing temperature and the post-rolling cooling speed are controlled in the application, the red rust-like iron oxide scale is formed on the surface of the free-cutting steel wire rod, the thickness of the iron oxide scale on the surface of the free-cutting steel wire rod is controlled to be below 12 microns, the inclusions and the banded structure are uniformly distributed, and the application is suitable for producing the free-cutting steel with the specifications of 6.5-17 mm and S=0.28%-0.40%.

The invention discloses an iron oxide / nickel ferrite composite nanorod and a synthesis method thereof, and belongs to the technical field of nano materials. The obtained composite nanorod is of a polycrystalline structure and is composed of a rhombohedral Fe2O3 crystal phase and a cubic NiFe2O4 crystal phase. The diameter of the composite nanorod is 10-100 nm, and the length of the composite nanorod is greater than 500 nm. The synthesis method comprises the following steps: dissolving ferric acetate and nickel acetate in deionized water, heating to 80-100 DEG C, preserving heat for 1-5 hours, cooling and drying to obtain a ferric oxide / nickel ferrite precursor; fully mixing the ferric oxide / nickel ferrite precursor with calcium chloride and sodium chloride, then putting the mixture into a corundum crucible, putting the crucible into a reaction furnace, and keeping the temperature at 800-1000 DEG C for 5-10 hours; the synthesis process is simple, complex equipment is not needed, control is easy, and the iron oxide / nickel ferrite composite nanorod has a large number of catalytic active sites, is expected to have good interface performance, catalytic activity and electrical and magnetic performance and has good application prospects in the aspects of catalysts, electrical devices and magnetic devices.

The invention discloses a dezincification process for steelmaking dust sludge of a rotary kiln, and belongs to the technical field of metallurgical solid waste resource utilization. According to the method, Fe2O3 in the dust sludge is preliminarily reduced into Fe3O4 and a small amount of FeO through the coke powder, H2 is generated through lignite pyrolysis to replace part of C for reduction, and efficient reduction and separation of zinc and iron in the dust sludge through carbon-hydrogen compounding in the rotary kiln are achieved. According to the method, the brown coal is excessively added, so that ferric oxide in the raw materials is fully reacted, meanwhile, oxygen is isolated by controlling the state of the kiln head, kiln slag is recycled after being cooled, FeO is prevented from being formed again, the ring forming phenomenon of the rotary kiln is relieved, and then the continuous working time of the rotary kiln is prolonged.

To provide a ferrite composition that can reduce magnetic loss in a larger magnetic core, and also to provide a magnetic core, an electronic component, and a power supply having the composition.SOLUTION: A ferrite composition has a main component and a sub-component. The main component includes 52.0 to 53.5 mol% of iron oxide in terms of Fe2O3, 6.0 to 11.0 mol% of zinc oxide in terms of ZnO, and manganese oxide as the balance. The ferrite composition contains, as the sub-component relative to 100 pts.mass of the main component, cobalt, titanium, silicon, calcium, vanadium, and tantalum, and zirconium in an amount of 0.004 pt.mass or less (including 0) in terms of ZrO2.SELECTED DRAWING: None

The invention relates to a comprehensive utilization method of copper tailings, which comprises the following steps: S1, carrying out mineral separation on the copper tailings to obtain alunite, sulfur concentrate, middlings and quartz tailings; performing flotation on the quartz tailings to obtain high-purity quartz and flotation quartz; s2, the middlings in the step S1 and flotation quartz with the weight not lower than 90% are mixed, silicon oxide and iron oxide are separated, and a mixture is obtained; s3, mixing the mixture in the step S2 with the neutralized slag and limestone, and roasting at 1000-1450 DEG C to obtain cement clinker; the neutralization slag is solid waste generated after acid wastewater and / or waste gas are / is neutralized by lime. According to the method disclosed by the invention, the effective components in the middlings and the quartz tailings after the copper tailings are beneficiated can be efficiently utilized to obtain the cement meeting the quality requirement of GB 175-2023, so that the copper tailings and the neutralization slag are massively absorbed, the resource shortage is effectively relieved, the environmental problem caused by solid waste stockpiling is reduced, and the ecological benefit, the economic benefit and the social benefit are remarkable.