33 results about "Iron(II) oxide" patented technology

The present application belongs to the field of smelting process, and particularly relates to a smelting process for reducing the content of ferrous oxide in slag. The present application effectively reduces the content of ferrous oxide in slag by optimizing the oxygen feeding time, adjusting the position of the oxygen lance, combining with the point-to-point injection of carbon powder and specific power supply process parameters, reduces the content of ferrous oxide to 13% to 17%, and also reduces the oxygen consumption, smelting cycle and smelting power consumption, the average oxygen consumption is 17.74 Nm 3 / t, the average smelting cycle is 49.0 min / oven, and the average smelting power consumption is 433.71 kWh / t, which greatly reduces the smelting cost. Due to the reduction of ferrous oxide in slag, a large amount of iron loss in the slag discharge process is avoided, which is of great significance for low-cost smelting of scrap steel in an electric furnace.

The invention provides a red foamed ceramic wall body material. The red foamed ceramic wall body material is prepared from the following raw material components in parts by weight: 50 to 78 parts of waste glass powder, 0 to 20 parts of fly ash, 10 to 20 parts of magnesium-iron hydrotalcite, 10 to 20 parts of limestone and 2 to 5 parts of borax. According to the invention, magnesium iron hydrotalcite is subjected to in-situ decomposition to generate pleonaste, the red color of ferric ions is retained, the red foamed ceramic is prepared, and black ferrous oxide or ferroferric oxide is prevented from being generated.

The invention discloses a resourceful treatment method for stainless steel pickling waste liquid and waste water. The waste liquid is divided into high-concentration waste liquid and low-concentration waste liquid according to the acid concentration and the salt concentration to be treated respectively. Sequentially recovering gypsum, chromic hydroxide, nickel sulfide, ferrous hydroxide and manganese-rich slag from the low-concentration waste liquid through gradient precipitation; and neutralizing free acid from the high-concentration waste liquid by using ferrous hydroxide generated in a low-concentration section, cooling and crystallizing to recover ferrous sulfate, deeply removing nickel by using nickel sulfide generated in the low-concentration section, and precipitating to recover chromium hydroxide. In the whole process, generation of ferric iron is strictly controlled, and high-value productization recovery of free acid and all metals is achieved. The method has the advantages of low medicament consumption, high metal recovery rate, high product value, no secondary pollution and the like.

The invention relates to integrated preparation and synthetic ammonia application of a cobalt-ferroferric oxide / ferrous oxide loaded foam iron self-supporting electrode. The invention relates to a preparation method and application of a cobalt-ferroferric oxide / ferrous oxide loaded foam iron (Co-Fe3O4 / FeO (at) IF) self-supporting electrode with high ammonia yield and Faraday efficiency in the field of nano materials. The invention aims to solve the problems of low electrochemical nitrate reduction synthesis ammonia yield and low Faraday efficiency. The preparation method comprises the following steps: taking cobalt nitrate hexahydrate and 2, 5-dihydroxy terephthalic acid (H4DOBDC) as raw materials, preparing Co-MOF-74 through a one-step hydrothermal reaction, then preparing a Co / Fe-MOF-74 (at) IF precursor material from foam iron (IF), the Co-MOF-74 and the H4DOBDC, and finally, successfully preparing the cobalt-doped self-supporting electrode Co-Fe3O4 / FeO (at) IF with high ammonia yield and Faraday efficiency through tube furnace calcination. The electrode can be directly used as a working electrode for electrocatalytic nitrate reduction synthesis of ammonia.

The invention discloses a metal oxide composite sodium ferric sulfate positive electrode material as well as a preparation method and application thereof, and belongs to the technical field of sodium ion battery positive electrode materials. The metal oxide composite sodium ferric sulfate positive electrode material comprises the following raw materials in parts by mass: 1-20 parts of sodium sulfate, 2-40 parts of ferrous sulfate, 0.05-1 part of an antioxidant, 0.05-1 part of a carbon source and 0.01-2 parts of metal oxide, the metal oxide is at least one of ferrous oxide, ferric oxide, ferroferric oxide, manganese oxide, manganese dioxide, cobalt oxide, cobaltosic oxide, cobaltic oxide, vanadium monoxide, vanadium dioxide, vanadium trioxide, vanadium pentoxide, nickel oxide and copper oxide. The invention also discloses a preparation method and application of the metal oxide composite sodium ferric sulfate positive electrode material. The method provided by the invention can solve the problems of low conductivity and specific capacity of the existing sodium ferric sulfate positive electrode material, and has the advantages of low cost, strong process adaptability and wide application prospect.

The application discloses a preparation method of zero-valent iron with a high Fe(II) content magnetite interface by regulating the redox intensity, and belongs to the field of water treatment. The method comprises the following steps: uniformly mixing zero-valent iron particles and ferrous ion solution at 20 DEG C-30 DEG C, regulating the initial pH value to 1-4 by using a sulfuric acid solution, adding a sulfur ion solution after 20 min of reaction and reacting for another 5 min, wherein the mass ratio of the added sulfur ion to the initial ferrous ion is 0.2-0.4:1; after the reaction is completed, the zero-valent iron particles are separated by magnetism, and are dried in a vacuum oven at 40 DEG C-60 DEG C for 4-12 h to obtain Fe3O4@mZVI materials. The zero-valent iron composite material with a high Fe(II) content magnetite interface prepared by the method can be prepared in an open system without controlling the anaerobic reaction atmosphere environment. Meanwhile, the ferrous ion is oxidized by using air, and no external oxidizing agent is needed, so that the method has the advantages of simple and rapid preparation and low cost. In the preparation process, the sulfur ion is added to regulate the redox reaction degree, the proportion of Fe(II) on the material surface is significantly improved, and the zero-valent iron composite material has better reaction activity and durability for pollutant removal.

The application relates to the technical field of refractory materials, in particular to an aluminum-carbon brick for refining ladle walls and a preparation process thereof, which comprises tabular corundum aggregates, alpha-type alumina micropowder, flaky graphite, oxide composite powder, silicon carbide-based composite powder, lanthanum-hafnium composite oxide nanometer powder, aluminum powder, carbon black and thermosetting phenolic resin. The oxide composite powder accelerates the reduction reaction of ferrous oxide on the surface of the brick body, so that the ferrous oxide is rapidly consumed by carbon in a very shallow layer on the contact surface of the brick, and the penetration of the ferrous oxide into the interior of the brick body is prevented; the silicon carbide-based composite powder fixes the liquid iron obtained by surface reduction in situ, so that the liquid iron cannot freely flow and contact the refining slag again; the lanthanum-hafnium composite oxide nanometer powder strengthens the structural stability, and the obtained brick body can better meet the use requirements of long-term high-strength service of the refining ladle walls.

The application provides a method for high-precision control of the surface oxide layer of welding wire and relates to the technical field of welding. The method comprises the following steps: cooling the billet in a crystallizer to 250-300 DEG C under a nitrogen environment; performing 2-3 times of cyclic heat treatment, wherein the cyclic heat treatment comprises temperature rising treatment and temperature dropping treatment in sequence, so that the surface of the billet changes from ferrite to austenite, and an austenite layer is obtained; the final temperature of the temperature rising treatment is 900-950 DEG C, and the final temperature of the temperature dropping treatment is 100-150 DEG C; and performing oxidation treatment on the billet comprising the austenite layer in a gas containing oxygen, so that the austenite layer is oxidized into a ferrous oxide dense layer. The method for high-precision control of the surface oxide layer of welding wire provided in the application controls the form and thickness of the oxide layer in the welding wire preparation process, so that the oxide layer can be accurately and completely removed, and high-quality welding wire is prepared.

The application discloses a method for improving PPTC stability by using metastable oxide and PPTC, and belongs to the field of thermistors and circuit protection. The method comprises the following steps: mixing tungsten carbide powder and metastable oxide powder, vacuum drying to obtain dry modified tungsten carbide powder; and blending the dry modified tungsten carbide powder with polyvinylidene fluoride (PVD F ) to prepare PPTC. The application utilizes the instability of metastable oxides such as ferrous oxide (FeO) to make it react with oxygen in the environment in preference to tungsten carbide, thereby playing the roles of "sacrificial protection" and "oxygen scavenger", and the generated stable oxide further forms a barrier layer. It is verified by experiments that the PPTC prepared by the application has a significantly reduced resistance change rate after aging in a double-85 high temperature and high humidity environment, and has higher environmental stability.

The invention discloses a full-recycling process and system for pickling wastewater generated by rare earth ore hydrometallurgy, which comprises the following steps: feeding the pickling wastewater into a calcium sulfate pre-crystallization reactor to react with lime emulsion under a low pH condition to obtain calcium sulfate crystals, feeding sulfur removal wastewater into a calcium fluoride crystallization reactor to increase pH, and reacting with a lime solution to obtain calcium fluoride crystals; carrying out filter pressing on the fluorine-removed water to obtain silicon dioxide precipitate, enabling filter-pressed water to enter a ferrous hydroxide crystallization reactor to react with sodium hydroxide to obtain ferrous hydroxide crystals, enabling molten iron to enter a magnesium hydroxide crystallization reactor to react with sodium hydroxide to obtain magnesium hydroxide crystals, enabling magnesium-removed water to enter a neutralization regulating tank, adding acid for neutralization, and discharging after reaching the standard. According to the method, the pollution problem of the rare earth ore pickling wastewater is solved, resource recycling of multiple valuable components in the wastewater is achieved, particularly, the purity of the obtained calcium fluoride product is higher than 70%, the calcium fluoride product can be used in the fields of metallurgy and the like, and the value of the resource product is greatly improved.

A cathode and an aluminum-ion battery, the cathode containing an active material, said active material being manganese dioxide, ferric oxide, ferrous oxide, magnetite, copper oxide, graphite, or metal carbonitride, wherein said metal element includes at least one selected from gold, silver, copper, platinum, palladium, iron, cobalt, and nickel.

The present application relates to the technical field of the comprehensive utilization of resources, and in particular to a comprehensive utilization method for iron ore. The comprehensive utilization method for iron ore comprises the following steps: S1. preparing iron ore into pellets and performing a reduction reaction on the pellets to obtain direct reduced iron; S2. smelting the direct reduced iron to obtain molten slag and molten iron, wherein the content of ferrous oxide in the molten slag is 1 wt% to 4 wt%; and S3. directly hot preparing rock wool from the molten slag online. Different from the prior art, the present application involves the addition of a carbonaceous reducing agent during smelting, reducing the content of ferrous oxide in the obtained molten slag, and improving the thermal insulation performance and tensile mechanical performance of the prepared rock wool, thereby improving the energy-saving effect, durability and safety of the rock wool while increasing the yield of obtained metals, increasing the yield of molten iron, and improving economic benefits.

The invention belongs to the technical field of metal smelting, and provides a method for preparing high matte nickel from low-grade limonite type laterite-nickel ore. Comprising the steps that the low-grade limonite type laterite-nickel ore and a reducing agent are mixed and heated to 900-1150 DEG C, smelting is conducted for 0.5-1 h, and a reduced material is obtained; adding lime into the reduced material, introducing continuous carbon dioxide, smelting for 2-4 hours, heating to 1400-1700 DEG C, and discharging slag; silica is added, after sulfur is sprayed into the bottom of the molten liquid, air is continuously introduced, and slag is discharged after smelting is conducted for 0.5-1 h; and silica is added, air is continuously introduced, molten metal is discharged after smelting is conducted for 5-7 h, and the high matte nickel is obtained. Firstly, a reducing agent is used for reducing most of iron and nickel into simple substances from oxides, then carbon dioxide, sulfur and air are used for converting the iron simple substances into oxides, sulfides and ferrous oxide in sequence, slagging removal is carried out along with silica, and the remaining matte phase becomes high matte nickel.

This invention discloses a method and system for online reconstruction of mineral phases in high-temperature steel slag, belonging to the field of steel slag resource utilization technology. The method involves crushing coal gangue and room-temperature steel slag to a particle size of 0.5 to 3 mm, mixing them at a mass ratio of 1:0.5 to 1.5 to prepare a reconstruction adjuster, and then adding the reconstruction adjuster and high-temperature liquid steel slag (temperature above 1350℃) to a mixing furnace at a mass ratio of 0.1 to 0.5:1. After settling, the mineral phase reconstruction is completed, converting free calcium oxide into dicalcium silicate and tricalcium silicate, magnesium oxide, ferrous oxide, and manganese oxide into the RO phase, and ferric oxide into ferrous oxide and elemental iron. The mixture after the reaction is cooled to below 500℃, then crushed, magnetically separated, and ground to a specific surface area of ​​400 square meters per kilogram to obtain a cementitious material. This invention utilizes the sensible heat of the high-temperature steel slag itself, eliminating the need for additional heating, achieving high-value utilization of solid waste. The prepared cementitious material exhibits high hydration activity and good volume stability. The process is simple and easy to implement, contributing to the metallurgical industry's achievement of dual-carbon goals.

The application belongs to the technical field of chlorine precipitation electrocatalysis, and particularly relates to a ferrous oxide-graphene composite electrode and a preparation method and application thereof. The application provides a ferrous oxide-graphene composite structure obtained by simply ball milling a mixture of graphite powder and ferric nitrate, wherein the graphite powder is converted into graphene with a smaller size and a thinner thickness, and the surface of the graphene is loaded with ferrous oxide nanoparticles. The composite structure is dispersed in anhydrous ethanol, Nafion solution is added, and then the composite structure is coated on the surface of carbon cloth and naturally dried to obtain the ferrous oxide-graphene composite electrode. The composite electrode does not use noble metal, and the CER electrocatalytic activity of the composite electrode is higher than that of DSA, and the composite electrode has the characteristics of low cost and high activity.

The invention belongs to the technical field of casting, and provides an oxygen-sulfur composite inoculant and a preparation method thereof, the oxygen-sulfur composite inoculant is prepared from ferrosilicon, ferromanganese, silicon calcium, silicon barium, ferrous sulfide, manganese dioxide, iron oxide and ferrous oxide; comprising 70 to 75 wt% of silicon, 1 to 1.5 wt% of calcium, 1 to 1.5 wt% of barium, 3 to 5 wt% of manganese, 0.6 to 1 wt% of sulfur, 1 to 1.5 wt% of oxygen and the balance of iron. When the oxygen-sulfur composite nucleating agent is applied, the problem that the internal graphitization effect cannot meet the basic requirement after an ultra-large casting is formed can be solved, the spheroidization level of the casting can reach the third level, the graphite size level basically reaches the sixth level, and then the requirement for the basic performance of the casting is met.

The invention discloses a method for preparing zero-valent iron with a high Fe (II) content ferroferric oxide interface by regulating and controlling oxidation-reduction strength, and belongs to the field of water treatment. The method comprises the steps that zero-valent iron particles and a ferrous ion solution are evenly mixed at the temperature of 20-30 DEG C, the initial pH is regulated to be 1-4 through a sulfuric acid solution, after the reaction is conducted for 20 min, a sulfur ion solution is added, the reaction is conducted for 5 min, and the mass ratio of added sulfur ions to initial ferrous ions is (0.2-0.4): 1; and after the reaction is finished, magnetically separating zero-valent iron particles, and drying in a vacuum oven at 40-60 DEG C for 4-12 hours to obtain the Fe3O4 (at) mZVI material. The zero-valent iron composite material with the high Fe (II) content and the ferroferric oxide interface prepared by the method does not need to control an anaerobic reaction atmosphere environment, and can be carried out in an open system. Meanwhile, air is utilized to oxidize ferrous ions, no additional oxidant is needed, and the method has the advantages of simple and rapid preparation and low cost. Sulfur ions are added in the preparation process, the oxidation-reduction reaction degree can be regulated and controlled, the Fe (II) proportion on the surface of the material is remarkably increased, and better reaction activity and durability are achieved for pollutant removal.

This invention discloses a method for detecting the structure of iron powder combustion products, belonging to the field of detection methods. This method measures elemental iron (Fe). 0 The content of ferrous iron (Fe) was determined. 2+ The content of ferric iron (TFe) was determined; the content of total iron (TFe) was calculated; and the content of ferric iron (Fe) was calculated. 3+ The content of oxide components was calculated, including ferrous oxide, ferric oxide, and magnetite. The radii of elemental iron, ferrous oxide, ferric oxide, and magnetite were also calculated. Reliable physical and chemical analysis units were used to obtain measurement data, and then mathematical calculations were performed to obtain accurate and reliable information on the composition and structure of iron powder oxidation products, providing a solid theoretical basis for the application of iron powder as a metal particle fuel.

The invention provides a method for controlling an oxide layer on the surface of a welding wire at high precision, and relates to the technical field of welding. The method comprises the following steps: cooling a steel billet in a crystallizer to 250-300 DEG C in a nitrogen environment; 2-3 times of circulating heat treatment is carried out, the circulating heat treatment sequentially comprises heating treatment and cooling treatment, so that the surface of the steel billet is changed into austenite from ferrite, and an austenite layer is obtained; wherein the final temperature of the heating treatment ranges from 900 DEG C to 950 DEG C, and the final temperature of the cooling treatment ranges from 100 DEG C to 150 DEG C; and the steel billet comprising the austenite layer is subjected to oxidation treatment in gas containing oxygen, so that the austenite layer is oxidized into a ferrous oxide compact layer. According to the method for high-precision control of the oxidation layer on the surface of the welding wire, the shape and the thickness of the oxidation layer in the welding wire preparation process are controlled, so that the oxidation layer is accurately and thoroughly removed, and the high-quality welding wire is prepared.

A method of treating contaminated water that has ferrous ions and at least one additional mineral in solution includes the steps of: adding a sufficient quantity of a caustic agent to the contaminated water to achieve a basic pH, and adding oxygen to the contaminated water to achieve a molar ratio of oxygen to ferrous iron of at least 1:10. The pH and the oxygen concentration are sufficient to produce ferrous hydroxide (Fe(OH)2) from ferrous ions and ferric hydroxide (Fe(OH)3) from the ferrous hydroxide while limiting colloidal iron formation, at least the ferric hydroxide forming a precipitate. The precipitate is separated from the contaminated water.

This invention discloses a method and system for depleting antimony blast furnace slag, belonging to the field of non-ferrous metallurgical technology. The method for depleting antimony blast furnace slag includes the following steps: S1, primary sedimentation separation: High-temperature molten slag from the antimony blast furnace at 1200-1250℃ undergoes preliminary sedimentation separation to separate a portion of crude antimony or antimony matte, obtaining primary treated slag; S2, secondary deep depletion: The primary treated slag undergoes deep depletion treatment; the deep depletion treatment includes: adding a reducing agent to the primary treated slag at 1200-1250℃ and stirring, reducing ferrous oxide in the molten slag to elemental iron, which then forms a high-density iron-antimony alloy with metallic antimony in the molten slag, resulting in a low antimony content in the final treated slag.

The invention discloses a long-acting response type functional iron-carbon-based alkali-activated material aiming at reduction resistance and control of high-concentration organic matters, and belongs to the field of environment functional cementing materials. The preparation method of the material comprises the following steps: under the condition of oxygen isolation, impregnating biochar in advance by using a ferrous salt aqueous solution so as to load ferrous ions to obtain a turbid liquid; adding magnesium oxide into the turbid liquid, and stirring and mixing to obtain a composite alkaline solution; and mixing the composite alkaline solution with the ash body material to obtain the long-acting response type functional iron-carbon-based alkali excitation material aiming at the reduction resistance and control of the high-concentration organic matters. An iron source is introduced through the biochar impregnated with ferrite, ferrous hydroxide is generated in pores of the biochar and a material matrix by means of an alkaline environment provided when the magnesium oxide activates the blocking and controlling material, high reducibility is achieved, and the material has the organic pollution (VOCs) degradation capacity; and the reduction product (Cl <->) promotes the formation of a hydrotalcite-like phase, so that the blocking and controlling material has good strength and low permeability.

The present invention relates to a process and a plant for reducing the iron III oxide contained in calcinated clay, the process comprising the steps of: introducing the calcinated clay containing iron III oxide into a reduction reactor (100); reducing the calcinated clay in the reduction reactor (100), said step comprising an operation O1) of contacting the calcinated clay with a reducing gas containing hydrogen atoms, to obtain reduced clay particles containing iron II oxide and / or magnetite and a flow of reducing gas to be treated; and cooling the reduced clay particles in a cooling circuit.

The invention discloses an electromagnetic valve leakage detection welding tool and a leakage detection welding method thereof, and belongs to the technical field of electromagnetic valve leakage detection welding. The electromagnetic valve leakage detection welding tool comprises an operation cabinet, a supporting plate is arranged in the operation cabinet, and a sliding groove is formed in the operation cabinet; the method further comprises the following steps that S1, the electromagnetic valve is placed between the clamping plates of the upper-layer fixing part and the lower-layer fixing part, the motor is started, and the driving end of the motor drives the tooth rollers of the fixing parts on the supporting plate to rotate through the second transmission belt. The method has the advantages that the leakage point of the electromagnetic valve can be quickly determined according to the color change reaction principle of the ferrous oxide solution; the electromagnetic valve can rotate on the fixing sleeve at a constant speed, an electric welding pen can conveniently and rapidly weld leakage points of the electromagnetic valve, the welding efficiency is improved, meanwhile, the electric welding pen can freely move within a controllable range through mutual cooperation of the sliding plate and the rotating component, and the flexibility of the device in the electromagnetic valve welding process is improved.

This invention provides a method for continuously manufacturing electric wire conductors in which the surface is insulated by an aggregate of stacked Maghemite microparticles that are magnetically attracted to each other by saturated magnetization. [Solution] The method involves creating a suspension in which maghemite microparticles are dispersed in an organic compound and the viscosity can be changed, continuously adsorbing the suspension onto a conductor, continuously covering the surface of the conductor with an aggregate of maghemite microparticles using the suspension, continuously saturating the magnetization of the maghemite microparticles, continuously winding up the conductor of the wire insulated with the aggregate of maghemite microparticles, creating a suspension in which an aggregate of fine crystals of an organic iron compound that precipitates ferrous oxide by thermal decomposition is dispersed in an organic compound with a high boiling point, thermally decomposing the organic iron compound, oxidizing the ferrous oxide to ferric oxide, reducing the viscosity of the suspension with an organic solvent, continuously immersing the conductor in the low-viscosity suspension, continuously vaporizing the organic solvent and organic compound from the conductor, continuously passing the conductor through a magnetic field, and continuously winding the conductor onto a bobbin.

The invention relates to the field of compound preparation, and discloses a method for preparing ferrocyanate by taking ferrous oxide as an iron source, the method comprises the following steps: contacting a raw material A containing ferrous oxide with a solution B of alkali metal cyanide, and reacting at 40-80 DEG C to obtain the ferrocyanate, the alkali metal cyanide comprising sodium cyanide and / or potassium cyanide. According to the method for preparing the ferrocyanate, sulfate containing ferrocyanide is not byproduct, the reaction temperature is mild, the cyanide hydrolysis phenomenon is basically avoided, the yield is high, NH3 and H2 are not released in the reaction process, the process is safe, and the method is a green process which is economical and reasonable in atom, free of byproduct and free of waste gas, waste residues and waste water. Compared with the traditional method, the method provided by the invention has the advantages of almost no three wastes, low production cost, high added value of products and better industrial prospect.

The present application relates to the field of metallurgy, in particular to a kind of control method for stabilizing sinter quality.Sinter is formed by sintering after sintering raw materials, and the sintering raw materials include iron-containing ore powder, fuel and flux.The content of ferrous oxide in sinter is controlled by controlling the particle size and moisture content of fuel and adjusting the amount of fuel added, and the alkalinity of sinter is controlled by controlling the quality of flux raw materials and adjusting the ratio of flux raw materials.The fuel is sintering anthracite, and the flux raw materials include combinations of quicklime, dolomite and limestone.The present application controls the content of ferrous oxide in sinter by controlling the particle size and moisture content of fuel and adjusting the amount of fuel added, and controls the alkalinity of sinter by controlling the quality of flux raw materials and adjusting the ratio of flux raw materials, thereby achieving stable control of the alkalinity and content of ferrous oxide in sinter, avoiding large-scale fluctuations in sinter quality, and improving the quality stability of sinter.

The present application belongs to the field of steelmaking, and particularly relates to a low-cost smelting method of low-carbon molybdenum-containing steel. The method comprises controlling a higher end-point C content in the converter tapping process to avoid over-oxidation of the molten steel and thus reduce iron loss; using a lower-cost high-carbon alloy to replace a high-cost low-carbon alloy in the converter tapping process; heating the molten steel and adjusting the composition of the molten steel to a certain range in the LF refining process; and adding molybdenum oxide balls containing ferrous oxide in the RH process under vacuum conditions to decarburize under vacuum and reduce the molybdenum oxide. According to the method of the present application, the converter tapping process does not need low-carbon tapping, and the oxidizability of the molten steel can be reduced to reduce iron loss. Meanwhile, the present application uses a low-cost high-carbon alloy and molybdenum oxide to replace a high-cost low-carbon alloy and molybdenum-iron alloy, respectively, and eliminates the high-energy-consumption and high-pollution molybdenum-iron smelting process, thereby greatly reducing the smelting cost of low-carbon molybdenum-containing steel.

The invention discloses a method for improving the stability of a PPTC (Polymeric Positive Temperature Coefficient) by utilizing metastable oxide and the PPTC, and belongs to the field of thermistors and circuit protection. The method comprises the following steps: mixing tungsten carbide powder with metastable oxide powder, and carrying out vacuum drying to obtain dried modified tungsten carbide powder; and blending the dried modified tungsten carbide powder with polyvinylidene fluoride (PVDF) to prepare the PPTC. The instability of metastable oxides such as ferrous oxide (FeO) is utilized, the metastable oxides react with oxygen in the environment prior to tungsten carbide, the effects of sacrificial protection and a deoxidant are achieved, and the generated stable oxides further form a barrier layer. Experiments prove that the resistance change rate of the prepared PPTC is remarkably reduced after the PPTC is aged in a double-85 high-temperature and high-humidity environment, and the PPTC has higher environmental stability.

This invention discloses a method for recovering iron, vanadium, and titanium from furnace slag, comprising the following sequential steps: S1, adding hot titanium-containing furnace slag, vanadium-containing tailings, and iron raw materials into an electric furnace and heating at 1300–1500°C for a predetermined time; wherein the titanium-containing furnace slag is a byproduct obtained from vanadium-titanium magnetite ironmaking in a blast furnace or non-blast furnace, the vanadium-containing tailings are the tailings remaining after vanadium removal from titanium tetrachloride, and the iron raw materials are ferrous oxide, ferric oxide, and / or iron; S2, adding a carbonaceous reducing agent to the electric furnace and performing reduction carbonization at 1500–1750°C; S3, discharging the slag and performing post-processing to obtain titanium carbide slag and ferrovanadium products. This invention can recover vanadium, titanium, and iron resources from titanium-containing furnace slag and vanadium-containing tailings, and can also reduce the iron content in titanium carbide slag, ensuring the product quality and stable operation of the entire process.