72 results about "Titanium chloride" patented technology

The invention discloses a high-temperature-resistant and salt-resistant fracturing fluid and a preparation method thereof, and relates to the technical field of oil field fracturing fluids. When the high-temperature-resistant and salt-resistant fracturing fluid is prepared, sodium 3-chloro-2-hydroxypropane sulfonate, N, N-dimethylacrylamide and ethylene glycol react to prepare a quaternized solid product, and then the quaternized solid product reacts with 1-bromooctadecane to prepare an amphoteric hydrophobic monomer; guar gum powder reacts with 3-(1-naphthyloxy)-1, 2-epoxypropane to prepare naphthyloxy functionalized guar gum, and then the naphthyloxy functionalized guar gum, acrylamide and an amphoteric hydrophobic monomer are subjected to initiated polymerization through ceric ammonium nitrate to prepare modified guar gum; enabling zirconium oxychloride octahydrate, titanium chloride, lactic acid, ethanediamine and glycerol to react to prepare an organic zirconium cross-linking agent; and finally, mixing the modified guar gum, an organic zirconium cross-linking agent, sodium thiosulfate, sodium bromate, a surfactant and water to prepare the high-temperature-resistant and salt-resistant fracturing fluid. The high-temperature-resistant and salt-resistant fracturing fluid prepared by the invention has excellent high-temperature resistance and salt resistance.

This invention relates to the field of titanium chemical technology and discloses a refining process for crude titanium tetrachloride, comprising: feeding crude titanium tetrachloride and a vanadium removal agent into the bottom of a distillation column, mixing them in the bottom, and completing the vanadium removal reaction; the material in the bottom is extracted by a refining circulation pump and heated, then returned to the upper middle part of the bottom for in-situ flash evaporation, and the flash-evaporated liquid phase falls back to the bottom of the bottom; the titanium tetrachloride vapor generated by flash evaporation enters the purification section at the top of the distillation column for distillation separation, and the refined titanium tetrachloride gas generated at the top is condensed and enters a reflux tank, part of which is returned to the top of the distillation column to control the distillation purity, and the other part is output as qualified refined titanium tetrachloride product. This invention also provides a system for implementing this process. This invention solves the technical problem that traditional processes require multiple separate devices such as a circulation pump tank and a flash evaporation tank, making production operation and condition control difficult.

The invention provides a coating method of high-silicon-content compact silicon-aluminum coated titanium dioxide, which comprises the following steps: S1) mixing titanium dioxide chloride, deionized water, a pH regulator and a dispersing agent to obtain oxidized slurry; the oxidized slurry is diluted and then heated, and then the pH of the slurry is adjusted; s2) adding sodium silicate and acid liquor into the slurry obtained in the step S1), and curing; s3) adding sodium silicate and acid liquor into the slurry obtained in the step S2), and curing; s4) adding sodium silicate and acid liquor into the slurry obtained in the step S3), and curing; s5) adding sodium silicate and acid liquor into the slurry obtained in the step S4) for curing; and S6) adding an aluminum source and an acid solution into the slurry obtained in the step S5), and curing to obtain the silicon-aluminum coated titanium dioxide. According to the coating method provided by the invention, by adopting a strategy of in-situ generation of nano seeds and layer-by-layer assembly, the bottleneck of coating densification of a titanium dioxide film layer with high silicon content is broken through, so that the silicon-aluminum coated titanium dioxide with low porosity and ultrahigh weather resistance is prepared.

The invention provides a process for purifying and refining industrial grade titanium tetrachloride, which comprises the following steps of: removing main impurities such as silicon tetrachloride, vanadium oxychloride, aluminum chloride, ferric chloride and titanium oxychloride in a titanium tetrachloride crude product by adopting a rectification method and a chemical method, and condensing into a titanium tetrachloride liquid; carrying out degassing treatment on the titanium tetrachloride liquid; filtering the titanium tetrachloride liquid by using an ultrafiltration membrane; filtering the titanium tetrachloride liquid by using a nanofiltration membrane; and crystallizing the titanium tetrachloride liquid to obtain a finished product of which the purity reaches 99.99% and the total content of metal impurities is less than 5ppb. Main impurities in a titanium tetrachloride crude product are removed through a rectification method and a chemical method, then titanium tetrachloride liquid is filtered through an ultrafiltration membrane and a nanofiltration membrane, and metal impurities are efficiently removed through surface negative charges of the nanofiltration membrane, so that a titanium tetrachloride finished product with the purity reaching 99.99% and the total content of the metal impurities being smaller than 5 ppb is obtained. The process steps are simplified, and the titanium tetrachloride purification efficiency is improved.

This invention discloses a method for preparing a test solution for impurity content in titanium tetrachloride using the sulfuric acid method, and a detection method thereof, belonging to the field of component detection and analysis technology. The preparation and detection methods are as follows: water is added to the titanium tetrachloride sample and reacted until the precipitate dissolves and no more dense white fumes are produced; the obtained product is heated to dryness at a temperature not exceeding 100°C; then sulfuric acid solution and an appropriate amount of water are added, and the mixture is heated at a temperature not exceeding 200°C until the titanium matrix is ​​completely dissolved, obtaining a clear and transparent solution. This solution is diluted with water to a final volume, yielding a test solution for impurity content in titanium tetrachloride with a sulfuric acid concentration of less than 2%; the impurity content in the solution is determined using ICP-MS or ICP-OES. This invention is simple to operate, effectively avoids the risk of contamination by foreign elements, reduces operational errors, and thus greatly improves the accuracy and reliability of the analytical results.

The utility model provides a titanium tetrachloride refines with organic vanadium removal agent heating device, including the bucket body, the inside fixed mounting of bucket body has multilayer spiral type's steam heating tube, is provided with the heat preservation layer between steam heating tube and bucket body, the inside fixed connection of bucket body has vanadium removal agent storage tank seat, vanadium removal agent storage tank is located on vanadium removal agent storage tank seat, steam heating tube surrounds vanadium removal agent storage tank in. The both ends of steam heating tube are connected with steam inlet and steam outlet that extend to the outside of bucket body, are provided with steam gate valve and flowmeter on steam inlet, the top of bucket body is installed with sealed top cover, the below of bucket body is equipped with temperature sensor. The utility model discloses a steam heating tube to vanadium removal agent storage tank heating can realize the heating and heat preservation of vanadium removal agent storage tank, also can avoid the corrosion problem of steam overflow to the equipment of the scene, can realize the control of heating temperature simultaneously.

The application discloses a preparation method of rutile titanium oxide long fibers, and belongs to the field of titanium oxide preparation. The preparation steps comprise the following steps: mixing titanium chloride, ethylene glycol and ethanolamine, stirring and refluxing, filtering to obtain a clear and transparent solution, rotary evaporation of the clear and transparent solution to obtain a concentrated rectification product, mixing the rectification product with ethyl methyl ketone, adding deionized water into the mixture, stirring and refluxing to obtain an organic titanium solution; adding polyvinyl alcohol into the organic titanium solution, uniformly stirring to obtain a stable spinning solution, electrospinning, heat treating the fibers after spinning to obtain rutile titanium oxide long fibers. The titanium oxide fibers prepared by the method are of rutile structure, the fibers are continuous, not adhered to each other and smooth in surface, the preparation method is simple, suitable for industrialization, and has a wide application prospect.

The invention discloses low-chlorine-content sponge titanium and a preparation method and device thereof. The preparation method comprises the steps that a titanium rod is placed in liquid magnesium, titanium tetrachloride is added, a reduction reaction is carried out, the titanium rod is moved out, and vacuum distillation is carried out; the vacuum distillation time is more than or equal to 10h / t-Ti, and the condensation temperature in vacuum distillation is less than or equal to 350 DEG C; when the condensate water is closed, the condensation temperature is in a decreasing trend and the temperature decreasing rate is greater than or equal to 3 DEG C / h, judging a distillation end point: stopping vacuum, calculating the H volatilization pressure rise rate after 10 minutes, and stopping vacuum distillation when the H volatilization pressure rise rate is less than or equal to 0.3 Pa / min; the volatilization pressure rise rate H is equal to L2 pressure rise rate minus L1 air leakage rate. According to the method, volatilization channels are additionally arranged in the liquid magnesium, so that the volatilization resistance of Mg / MgCl2 in pores of the sponge titanium is reduced; in addition, the vacuum distillation end point is judged by adopting a composite method, so that the production of the sponge titanium with low chlorine impurity content is realized.

The invention discloses a method for preparing high-purity titanium powder by taking titanium-aluminum waste as a raw material, which comprises the following steps: annealing a titanium-aluminum waste mixture at 400-600 DEG C in an inert atmosphere to remove organic waste in the titanium-aluminum mixed waste, and carrying out reduction deoxidation reconstruction on surface oxides of the titanium-aluminum waste by using reducing micromolecules generated by pyrolysis depolymerization of the organic waste, a clean titanium and aluminum mixture is obtained; the titanium and aluminum mixture is placed in the dense medium liquid, the aluminum material floats above the dense medium liquid, the titanium material sinks to the lower portion of the dense medium liquid, and separation is achieved; the method comprises the following steps: placing a titanium material in a closed reactor, reacting by using gaseous high-reactivity Lewis acid salt, and converting the titanium material into gaseous low-valence titanium chloride; the gaseous low-valence titanium chloride is guided into an inlet-outlet high-temperature-gradient high-temperature decomposition reactor in a high-frequency pulse mode, and is converted into high-purity titanium powder in the process of passing through the high-temperature decomposition reactor, and the high-purity titanium powder is deposited in a collection area of the reactor.

This invention relates to the field of titanium tetrachloride preparation technology, and proposes a method for preparing titanium tetrachloride products. The method includes: filtering titanium tetrachloride raw materials to remove insoluble solid impurities, obtaining a pre-filtered liquid; adding a reducing agent and a catalyst to the pre-filtered liquid to react, causing vanadium-containing impurities to be reduced and precipitated, then separating the precipitate to obtain a vanadium-removed clear liquid; subjecting the vanadium-removed clear liquid to countercurrent extraction, and separating the liquid to obtain a purified clear liquid; sequentially passing the purified clear liquid through a light-water removal tower to remove impurities with boiling points lower than titanium tetrachloride, and through a heavy-water removal tower to remove impurities with boiling points higher than titanium tetrachloride, and obtaining the purified titanium tetrachloride product from the top of the heavy-water removal tower. This invention achieves deep removal of multiple types of impurities from titanium tetrachloride raw materials, can stably obtain titanium tetrachloride products with purity meeting the requirements of high-end fields, and has the advantages of high operational safety, low energy consumption, and ease of industrial implementation.

The invention relates to the technical field of chemical intermediates, and relates to C07F, in particular to a preparation method for co-production of acetyl chloride and phosphorous acid as well as a product and application thereof. The preparation method at least comprises the following steps: S1, stirring and cooling acetic acid and a catalyst, dropwise adding phosphorus trichloride, heating to 20-45 DEG C, and reacting for 0.5-6 hours; s2, after the reaction is finished, carrying out negative pressure desolvation to obtain a crude product acetyl chloride, and continuously heating to remove excessive phosphorus trichloride, so as to obtain a crude product phosphorous acid; s3, rectifying the crude product acetyl chloride to obtain an acetyl chloride product; recrystallizing the crude phosphorous acid to obtain a phosphorous acid product; the catalyst comprises at least one of aluminum trichloride, ferric trichloride, titanium tetrachloride, ytterbium trifluoromethanesulfonate and iodine; the mass ratio of the acetic acid to the catalyst is 1: (0-0.003). The method provided by the invention has the characteristics of high conversion rate, high yield, high content, small amount of three wastes, no solvent pollution, simple process, easy industrial preparation of acetyl chloride and the like.

The utility model discloses a kind of feeding devices for refining titanium tetrachloride, it is related to chemical equipment technical field, including mineral oil storage tank, for storing high viscosity mineral oil, the outside of mineral oil storage tank is equipped with steam jacket, steam inlet and steam outlet are equipped on the steam jacket;Coarse titanium storage tank, for storing coarse titanium tetrachloride;Mixing tank, the discharge outlet of mineral oil storage tank is communicated with the mixing tank by feeding assembly, the discharge outlet of coarse titanium storage tank is communicated with the mixing tank by first material transmission pipeline, the mixing tank is communicated with the feed inlet of rectification system by second material transmission pipeline, the second material transmission pipeline is used to send coarse titanium tetrachloride-mineral oil mixed solution into the rectification system.Upper described feeding device for refining titanium tetrachloride, realizes the technical effect of improving refining efficiency and product quality, reduces pipeline jamming risk, guarantees the stable operation of production.

This invention belongs to the field of titanium tetrachloride preparation technology, specifically disclosing a method for improving the quality of titanium tetrachloride produced by molten salt chlorination. The method includes: adding a mixture of titanium-containing raw materials and a carbon reducing agent into a chlorination furnace containing molten salt, and introducing chlorine gas into the furnace to react and generate flue gas containing titanium tetrachloride; at the flue outlet of the molten salt chlorination furnace, using cooled liquid titanium tetrachloride to counter-currently spray the generated flue gas; passing the sprayed flue gas sequentially through a dust collection device and a multi-stage condensation and scrubbing tower to condense and liquefy the titanium tetrachloride in the flue gas and separate it from impurities, obtaining a crude liquid titanium tetrachloride product; and installing a fan at the tail gas emission end, adjusting the fan's operating parameters to ensure the system consisting of the molten salt chlorination furnace, dust collection device, and multi-stage condensation and scrubbing tower operates under pressure control. This invention stably reduces the solid content in titanium tetrachloride to below 4 g / L, while effectively reducing the content of impurities such as Fe and Al, thus improving the quality of titanium tetrachloride.

The invention belongs to the field of copolymerization catalysts, and particularly relates to a multicomponent olefin copolymerization catalyst and a preparation method and application thereof, and the preparation method comprises the following steps: mixing activated silica gel with pentane and triisobutylaluminum, and then evaporating a solvent to dryness; the method comprises the following steps: under a protective atmosphere, adding anhydrous magnesium chloride and ethanol into hexane, carrying out a heating reaction, and then adding tetraethoxysilane to obtain a mother solution 1; under the protective atmosphere, adding titanium tetrachloride and tetrahydrofuran into hexane, and continuously stirring to obtain mother liquor 2; mixing the mother liquor 1 and the mother liquor 2 in a protective atmosphere, then adding modified silica gel, and standing; taking the solid precipitate after standing, and washing; and mixing the washed solid precipitate with hexane, diethyl aluminum monochloride and ethyl aluminum dichloride, and then drying by distillation. Compared with the prior art, the catalyst provided by the invention solves the problem that a catalyst suitable for copolymerization of ethylene and various alpha-olefins is lacked in the prior art, and the prepared catalyst is suitable for copolymerization of ethylene and alpha-olefins by adding three alkyl aluminum compounds in the scheme.

The present application relates to the technical field of coagulant preparation, in particular to a coagulant for treating sewage and a preparation method thereof.The present application provides a preparation method of a coagulant for treating sewage, which comprises two steps of S1 coagulant reaction liquid preparation and S2 coagulant preparation.The coagulant is an inorganic-organic composite coagulant generated by mixing titanium chloride, magnesium chloride and methacryloyloxyethyl trimethyl ammonium chloride (DMC) in a certain proportion and reacting at low temperature.The coagulant has high flocculation and sewage removal capacity, is stable in nature, and can be used in sewage with different pH and different temperatures.

The utility model relates to the field of titanium tetrachloride detection, in particular to a titanium tetrachloride test sample preparation device, which comprises a first container, a second container and a third container, the second container comprises a first liquid inlet and a gas outlet; and the U-shaped pipe comprises a second liquid inlet and a second liquid outlet which are respectively communicated with the first liquid outlet and the first liquid inlet in an airtight manner, and the second liquid inlet and the second liquid outlet of the U-shaped pipe are respectively close to the bottoms of the first container and the second container. According to the system disclosed by the utility model, titanium tetrachloride and a hydrochloric acid solution can be mixed in a closed environment, so that a stable titanium tetrachloride sample is prepared, and the titanium tetrachloride sample mixed with hydrochloric acid cannot generate hydrochloric acid mist, heat and solid particles after meeting air, so that the detection operation is greatly simplified, and the detection efficiency is improved. And carbon deposition cannot be generated during flame combustion detection, so that the element detection accuracy is greatly improved.

The application provides a composite flocculant suitable for alkali reduction wastewater treatment and a preparation method thereof, and relates to the technical field of wastewater treatment; the method comprises the following steps: mixing magnesite tailings and sintered red mud according to a mass ratio of 1:3 and grinding to 200 meshes, and performing ladder calcination under the protection of nitrogen to obtain a magnesite-red mud mixture; a sodium silicate solution is adjusted to a pH of 3.5 by sulfuric acid, and after stirring to form a sol, titanium tetrachloride is added to perform temperature curing to obtain a prepolymer; hydrochloric acid is added to the magnesite-red mud mixture to perform reaction, and then calcium aluminate powder, the prepolymer and konjac glucomannan phosphate are added in sequence to perform stirring reaction; calcium hydroxide suspension liquid is added to adjust the alkalinity of the system to 75-80%, and after static curing, the composite flocculant is obtained; through the multi-metal cooperation of aluminum, iron, magnesium, titanium and calcium, a four-dimensional flocculation mechanism of "electric neutralization-precipitation-net capture-bridging" is realized, and the problem of easy gelation instability of traditional polysilicate aluminum salt is solved.

The utility model relates to the technical field of titanium tetrachloride production, in particular to a thermocouple for measuring high-temperature chlorinated fused salt, which comprises a protective sleeve, a junction box mounted at one end of the protective sleeve, a patch board mounted inside the junction box, a binding post mounted on the patch board, a thermocouple core arranged inside the protective sleeve and comprising two electrodes. One ends of the electrodes are welded together through laser, the other ends of the electrodes are led out through wires to be connected to binding posts, and the electrodes and the wires are sleeved with insulating sleeves. According to the thermocouple for measuring the high-temperature chlorinated fused salt, the electrode material formed by combining the nickel-based alloy and the platinum-rhodium alloy, the tantalum-zirconium alloy protection sleeve, the high-temperature ceramic powder insulation sleeve, the corrosion-resistant and explosion-proof polytetrafluoroethylene junction box and the like are innovatively designed; the corrosion resistance, the measurement precision and the service life of the thermocouple in a high-temperature chlorinated molten salt environment are remarkably improved, meanwhile, good insulation performance and anti-explosion safety are ensured, and installation and maintenance are convenient.

The invention relates to an ordered porous carbon material as well as a preparation method and application thereof. The preparation method is a one-step synthesis method and comprises the following steps: uniformly mixing a titanium source and a resin raw material in proportion, and drying to obtain a mixed raw material; the titanium source comprises at least one of lithium titanate, titanium tetrachloride and tetraethyl titanate; the resin raw material comprises at least one of melamine resin, nitrogenous phenolic resin and nitrogenous furan resin; heating the mixed raw material to 800-1300 DEG C in an inert gas atmosphere, carrying out heat preservation for a certain time, and carrying out carbonization treatment to form a carbon material with an oxidation state and a titanium nitride modified ordered porous structure, namely the titanium oxide and titanium nitride modified ordered porous carbon material; an O-T -C-N-T heteroatom covalent network structure formed after carbonization treatment is formed at an interface layer of the titanium oxide and titanium nitride modified ordered porous carbon material. According to the method, by controlling the carbonization temperature and the ratio of the titanium source to the resin raw material, the order degree of the porous carbon can be improved, and the lithium storage and conductivity of the porous carbon can be improved.

The invention provides a solid-state battery negative electrode material and a preparation method thereof. The preparation method comprises the following steps: adding silicon powder, titanium tetrachloride and zirconium tetrachloride into ethanol, adding a dispersing agent, and dispersing to obtain a mixed suspension; reacting the mixed suspension with a reducing agent to obtain a silicon-titanium-zirconium composite precursor; the silicon-titanium-zirconium composite precursor is subjected to first calcination, and silicon-titanium-zirconium composite nanoparticles are obtained; dispersing the silicon-titanium-zirconium composite nanoparticles, glucose, urea and boric acid in water to obtain a particle suspension; carrying out hydrothermal reaction on the particle suspension to obtain a core-shell precursor; performing secondary calcination on the core-shell precursor to obtain core-shell structure composite particles; mixing and grinding the core-shell structure composite particles with lithium carbonate, aluminum oxide and ammonium dihydrogen phosphate to obtain mixed powder; and carrying out third calcination on the mixed powder. The solid electrolyte provided by the invention has the advantages of reduced volume expansion rate, high specific capacity, long cycle performance and good rate capability.

The application provides a method for preparing titanium tetrachloride by using a fluidized bed, wherein the powder fluidization area and the cooling area are alternately arranged in the fluidized bed, the whole is in a rectangular structure, the powder material is added from one side of the fluidized bed, and is sequentially overflowed through several fluidization areas and cooling areas and then discharged from the outlet; the fluidization gas enters the fluidized bed through the distribution plate at the bottom of the fluidization area, and reacts with the added powder particles at a certain temperature to prepare titanium tetrachloride; and the cooling medium is sent from the bottom of the fluidized bed and discharged from the top outlet after heat exchange. The method uses the slag containing titanium carbide, titanium nitride or titanium carbonitride as the raw material, and reacts with chlorine gas, so that the reaction efficiency is high; the fluidized bed adopts the cross design of the fluidization area and the cooling area, so that the heat released by the chlorination reaction is discharged from the fluidized bed through the cooling medium in time, and the local heat release of the reaction is avoided, and the sintering of the material or even the dead furnace condition is avoided.

An apparatus includes a body configured to support a substrate, a first coating, conformal on a surface of the body, that is corrosion resistant to at least one of: boron trichloride, nitrogen trifluoride, hafnium tetrachloride, aluminum trichloride, oxygen gas, chlorine gas, fluorine gas, chlorine trifluoride, hydrogen fluoride, hydrogen gas, ammonia, tungsten hexafluoride, tetrafluoromethane, titanium tetrachloride, molybdenum pentachloride, ozone, tetrafluorosilane, or hexafluoroethane, and a second coating, on the first coating, having a hardness that greater than or equal to about 8 gigapascals.

The utility model relates to the field of chemical production, in particular to a titanium tetrachloride cold recycling device which comprises a cold titanium tetrachloride storage tank, the device further comprises an atomizing spray head and a spray nozzle, the upper end of the cold titanium tetrachloride storage tank is fixedly connected with a supporting frame, the upper end of the supporting frame is fixedly connected with a second-stage condenser, a direct cooler and a third-stage condenser, and the inner wall of the direct cooler is fixedly connected with an annular flow dividing pipe. According to the utility model, through the use of the atomizing spray head and the spray nozzle, spraying is carried out from different angles and positions, mixed gas is further cooled, and part of gas is liquefied and flows into the cold titanium tetrachloride storage tank along the storage hopper, so that the cooling area and the uniformity are increased, and the liquefaction efficiency and the cooling effect are improved; a gas-liquid mixture is fed into a third-stage condenser for deep cooling, residual titanium tetrachloride gas is completely liquefied and flows into a cold titanium tetrachloride storage tank, liquid titanium tetrachloride in the storage tank is pressurized through a circulating system and then is fed back to a direct cooler to be used as a cooling medium, and the cooling and liquefying efficiency is improved.

This invention relates to the field of online exhaust gas detection technology, specifically to a pretreatment device for detecting titanium tetrachloride exhaust gas. The device includes an exhaust gas pipeline with a sampling pipeline connected to one side for sampling chlorination furnace exhaust gas. Along the gas flow direction, the sampling pipeline is sequentially equipped with a solid-liquid separation mechanism, a gas collection mechanism, and a real-time analysis mechanism. The solid-liquid separation mechanism includes several condensing plates for settling dust and condensing high-boiling-point compounds, and a connecting pipe for collecting low-boiling-point test gases. The gas collection mechanism includes a power component for generating negative pressure to draw in the low-boiling-point test gases and a storage tank for storing the low-boiling-point test gases. The real-time analysis mechanism analyzes the gas content corresponding to the low-boiling-point test gases in the storage tank and controls the power output of the power component based on the residual temperature inside the storage tank. This device reduces the content of dust and high-boiling-point compounds in industrial process exhaust gas, ensuring the accuracy of CO, CO2, HCl, and Cl2 gas content measurements in chlorination exhaust gas.

This invention discloses a hollow aluminum titanate ceramic fiber and its preparation method. The steps are as follows: Milkweed fiber is selected as a template, and ethanol is used as a solvent. The milkweed fiber is immersed in a mixed solution composed of aluminum nitrate, titanium tetrachloride, and yttrium nitrate. Titanium tetrachloride and aluminum nitrate penetrate into the milkweed fiber wall, and yttrium nitrate acts as a stabilizer. After immersion, the milkweed fiber is removed, drained, and dried to prevent uneven shrinkage and cracking during sintering. Then, sintering is performed at high temperature. The precursor in the milkweed fiber wall forms aluminum titanate, while the fiber decomposes and ablates at high temperature, leaving hollow aluminum titanate fibers. Finally, annealing is performed to obtain stable hollow aluminum titanate ceramic fibers. This invention has a simple and stable process, and the prepared fibers have high hollowness, good thermal shock resistance, and excellent thermal insulation performance, with lower thermal conductivity compared to conventional solid aluminum titanate fibers.

The application provides a method for controlling the particle size of titanium dioxide primary product in a chlorination process, which comprises the following steps: high-temperature O2 enters an oxidation reactor through a combustion chamber, and TiCl4 vapor enters the oxidation reactor through a TiCl4 feeding ring; the high-temperature O2 and the TiCl4 vapor react in a mixing reaction zone of the oxidation reactor to generate TiO2 powder; CsCl particles are sprayed into the oxidation reactor at the rear end of the feeding ring adjacent to the oxidation reactor; at least one magnetic field is applied to the mixing reaction zone and / or a cooling conduit, and the magnetic field parameters are set according to the target particle size of the titanium dioxide primary product. The application also provides a method for removing scars of an oxidation reactor for titanium dioxide in a chlorination process. The application also provides a device for controlling the particle size of titanium dioxide primary product in a chlorination process. The method of the application effectively solves the problem of scarring of the furnace wall from the rear end of the feeding ring to the high-temperature reaction core area of the oxidation reactor, and the average particle size of the titanium dioxide primary product produced reaches 180-260 nm, the purpose of optimizing the particle size distribution is achieved, and thus the quality of the titanium dioxide primary product in the chlorination process can be stabilized.

The present invention relates to the field of copolymerization catalysts, and in particular to a multi-olefin copolymerization catalyst, a preparation method therefor, and a use thereof. The method comprises the following steps: mixing activated silica gel with pentane and triisobutylaluminum and then evaporating the solvent to dryness; in a protective atmosphere, adding anhydrous magnesium chloride and ethanol to hexane, reacting the mixture under heating, and then adding ethyl orthosilicate to obtain a mother solution 1; in a protective atmosphere, adding titanium tetrachloride and tetrahydrofuran to hexane and continuously stirring the mixture to obtain a mother solution 2; in a protective atmosphere, mixing the mother solution 1 with the mother solution 2, then adding a modified silica gel, and leaving the mixture to stand; after standing, taking a solid precipitate and washing same; and mixing the washed solid precipitate with hexane, diethylaluminum monochloride and ethylaluminum dichloride and then evaporating the solvent to dryness. Compared with the prior art, the present invention solves the problem of the lack of a catalyst suitable for the copolymerization of ethylene and various α-olefins in the prior art. The catalyst prepared in the present solution by adding the three alkylaluminum compounds is suitable for the copolymerization of ethylene and α-olefins.

A method for producing an electrothermal film, its precursor solution, and related heating devices. The solution consists of tin tetrachloride (SnCl₄), titanium tetrachloride (TiCl₄), zinc oxide (ZnO)

The application discloses a high-yield preparation process of tetrachlorophthalic anhydride, relates to the technical field of organic synthesis, and comprises the following steps: dissolving phthalic anhydride in chlorosulfonic acid, adding into a chlorination kettle, adding a catalyst, then performing temperature rising according to a certain procedure, starting to pass in chlorine when the temperature in the reaction kettle rises to 80-100 DEG C, adjusting and controlling the flow of chlorine, reacting while stirring, absorbing tail gas by using lye, and stopping the reaction when there is substantially no HCl gas escaping; filtering the material, recovering the catalyst solvent, and ensuring that the distillation temperature is not higher than 220 DEG C; after cooling, washing with cold water, centrifugal dehydration, and drying at 150-170 DEG C, tetrachlorophthalic anhydride is obtained; wherein the catalyst is a modified montmorillonite supported titanium tetrachloride catalyst. The preparation process of tetrachlorophthalic anhydride provided by the application has high yield and high purity, and is easy to be industrialized.