The method of producing titanium dioxide
(57) Abstract:The invention relates to the production of titanium dioxide by vapor-phase hydrolysis of titanium halide. The method of obtaining titanium dioxide includes obtaining gas mixture, the interaction of the mixture with pairs of titanium tetrachloride, an introduction to the process of vapor-phase hydrolysis of additives in the form of aluminium chloride and/or potassium chloride and silicon tetrachloride, and the Department of titanium dioxide from the reaction products. A pair of silicon tetrachloride is injected parallel to the movement of the vapor-gas mixture, and as an additive of silicon tetrachloride using waste from the distillation purification of titanium tetrachloride. The content of silicon tetrachloride in the waste from the distillation purification of titanium tetrachloride is 30-60 wt.%. Waste serves in the range of 0.1 to 1.0% in terms of silicon dioxide in the finished titanium dioxide. Before feeding into the reactor waste from the distillation purification of titanium tetrachloride is heated to a vapor state. The technical result of the invention improves the performance of the process vapor hydrolysis, to reduce the cost of purchasing raw materials, additives used in the process of hydrolysis. Use as an additive from the century 3 C.p. f-crystals. The invention relates to the production of titanium dioxide by vapor-phase hydrolysis of titanium halide.A method of obtaining titanium dioxide (CBL.UK application No. 1286760) in the vapor phase by burning a combustible gas to the burner when the tangential supply of oxygen. The resulting combustion products introduced into the reaction zone, which serves as a pair of titanium tetrachloride and water. The titanium tetrachloride can be added aluminum chloride and silicon tetrachloride.The disadvantages of this method of obtaining titanium dioxide are significant costs of producing pure oxygen and complex instrumentation.A method of obtaining titanium dioxide (U.S. Pat.U.S. No. 3467498, publ.16.09.1969), in which the Central tube serves oxygen, heated to the temperature T, the titanium tetrachloride is injected through coaxially disposed tube at speeds from 2.5 to 300 m/s at a temperature not exceeding 500 ° C, in the amount of 32 g mol/min. In a stream of titanium tetrachloride introduced a pair of aluminium chloride are heated to 300C. Here we introduce 0.18 g mol/min of liquid silicon tetrachloride.The disadvantage of this method is that the lower ends of the tubes are formed deposits dioxide is tan (patent RU №2169119, publ. 20.06.2001,, BIPM No. 17), the number of General characteristics taken as the closest analogue is the prototype. The method of obtaining titanium dioxide involves feeding preheated to a temperature of 200-400C of titanium tetrachloride into the reactor, the combustion air natural gas, the supply of water in the combustion products to obtain a gas mixture. Gas-vapor mixture is fed into the reactor for vapor-phase hydrolysis perpendicular to the flow of vapors of titanium tetrachloride. The ratio of titanium tetrachloride : gas-vapor mixture is 1:2-4. At the same time in the reactor an additive of aluminum chloride at an angle of 50-55 to the movement of vapors of titanium tetrachloride, additive potassium chloride serves perpendicular to the movement of the gas mixture.The disadvantage of this method is that the particles of titanium dioxide in the process of vapor-phase hydrolysis have a high surface activity, resulting acquire electric charges that cause mutual attraction of the particles, their adhesion and aggregation, it causes the sedimentation of aggregated particles of titanium dioxide on the inner side of the reactor, which significantly reduces the efficiency of the process increases the labor costs for cleaning of equipment, reduces the product yield.The technical result is achieved in that a method of obtaining titanium dioxide, including the production of vapor-gas mixture, the interaction of the mixture with pairs of titanium tetrachloride, an introduction to the process of vapor-phase hydrolysis of additives in the form of aluminium chloride and/or potassium chloride, separating the titanium dioxide from the reaction products, what's new is that as an additive impose additional silicon tetrachloride parallel to the gas-vapor mixture in the form of waste from the distillation purification of titanium tetrachloride.In addition, the content of silicon tetrachloride in the waste from the distillation purification of titanium tetrachloride is 30-60 wt.%.In addition, the waste serves in the range of 0.1 to 1.0% in terms of silicon dioxide in the finished titanium dioxide.In addition, before feeding into the reactor waste from the distillation purification of titanium tetrachloride is heated to vapor sostavljaet to handle particles of titanium dioxide compounds of silicon, to reduce adhesion of particles of titanium dioxide, to reduce their sedimentation on the inner surface of the reactor and thereby to improve the performance of the method.Use as an additive silicon tetrachloride waste distillation purification of titanium tetrachloride can reduce the cost of purchasing expensive supplements.Conducted by the applicant's analysis of the prior art, including searching by the patent and scientific and technical information sources, and identify sources that contain information about the equivalents of the claimed invention, has allowed to establish that the applicant had not found the source, which is characterized by signs, identical all the essential features of the invention. The definition from the list of identified unique prototype, as the most similar set of features analogue, has allowed to establish the essential towards perceived by the applicant to the technical result of the distinctive features in the claimed method of producing titanium dioxide set forth in the claims.Therefore, the claimed invention meets the condition of “novelty.”To check compliance with the s solutions to identify signs that match the distinctive features of the prototype of the characteristics of the claimed method. The search results showed that the claimed invention not apparent to the expert in the obvious way from the prior art because the prior art defined by the applicant, not the influence provided the essential features of the claimed invention transformations to achieve a technical result. Therefore, the claimed invention meets the condition of “inventive step”.An example of the method.Pre-purified titanium tetrachloride (TU 1715-455-05785388-99) served in the cube evaporator where it is evaporated at a temperature of 136-140 C, then the pair is served in the superheater, again heated to a temperature of 200-S and sent to the reactor for vapor-phase hydrolysis. In a separate furnace carry out the combustion of natural gas (GOST 5542-87) and compressed air (TU 05785388-009) at a temperature of 1100-1300C. In the furnace serves 50-300 kg/h of water while maintaining up to 20% above the stoichiometric amount required for the reaction of interaction with pairs of titanium tetrachloride. The combustion of 1 nm3natural gas spend 11-20 nm3air. Poluce m3/h and at a temperature of 800-1300C perpendicular to the flow of vapors of titanium tetrachloride into the reactor for vapor-phase hydrolysis, maintaining the ratio of titanium tetrachloride: vapor-gas mixture is equal to 1:(2-4). In the reactor a vapor-phase hydrolysis serves supplements in the form of vapors of aluminum chloride and/or potassium chloride and silicon tetrachloride. Aluminium chloride in solid form is heated in a separate tank to a vapor state and serves at an angle of 50-55 into the reactor at a speed of 2.5 to 5.0 kg/h Into the reactor for vapor-phase hydrolysis can be submitted simultaneously with the addition of potassium chloride, which serves perpendicular to the movement of the gas mixture. Silicon tetrachloride is a waste distillation purification tetrachloride titanium content of silicon tetrachloride 30-60%, heated in a separate tank to a vapor state and a pair of guide parallel to the movement of the vapor-gas mixture in the reactor. In the reactor at a temperature of 600-S pair of titanium tetrachloride interact with water by reactionsTiCl4(pairs)+2H2O(pairs)=TiO2(TV.)+4l+QReceived palaeohistology mixture is sent to the camera pre-cooling, where it is cooled to a temperature of 400-800C. Then carry out subsequent processing of dust and gas smea periodically discharged into the container. Receiving waste distillation purification of titanium tetrachloride containing silicon tetrachloride. After cleaning from the technical vanadium tetrachloride titanium content, wt.% vanadium 0,15, chlorine 0,12, silicon 0,006, the phosgene acetylchloride 0,008, pumped into the tank, then in pressure vessels distillation columns. From pressure tanks served in the heater, where it is heated to a temperature of not less than S, and sent to the middle part of the distillation column. Cleaning from boiling impurities, namely from silicon tetrachloride with a boiling point S, phosgene, chlorine, hydrogen chloride, carbon dioxide is carried out in a Packed distillation columns or columns with disastrous lattice / tube sheet or plate with overflow devices. Pair boiling liquid from the upper part of the distillation column enter the condenser-reflux condenser, where it is condensation. Get distillate containing, wt.%: 22-30 - liquid titanium tetrachloride with the contents of the boiling impurities, such as SiCl445-66, 1,5 CCL4, 13 COCl2. On existing technology waste wash water and sent to the sewer. In the cleaning process gain 1-2 kg of distillate per 1 ton of titanium tetrachloride (see kN. Corsim way the proposed set of essential features of the invention improves the performance of the method of obtaining titanium dioxide, to reduce the cost of cleaning equipment and the purchase of expensive additives. 1. The method of obtaining titanium dioxide, including the production of vapor-gas mixture, the interaction of the mixture with pairs of titanium tetrachloride, an introduction to the process of vapor-phase hydrolysis of additives in the form of aluminium chloride and/or potassium chloride, separating the titanium dioxide from the reaction products, wherein the additive further added silicon tetrachloride parallel to the gas-vapor mixture in the form of waste from the distillation purification of titanium tetrachloride.2. The method according to p. 1, characterized in that the content of silicon tetrachloride in the waste from the distillation purification of titanium tetrachloride is 30-60 wt.%.3. The method according to p. 1, characterized in that the waste serves in the range of 0.1 to 1.0% in terms of silicon dioxide in the finished titanium dioxide.4. The method according to p. 1, wherein the pre before it enters the reactor waste from the distillation purification of titanium tetrachloride is heated to a vapor state.
FIELD: mining industry.
SUBSTANCE: perovskite concentrate, which can be used for manufacture of pigment titanium dioxide for paints, paper, enamels, and plastics, is processed as follows. 1 kg of concentrate is treated under atmosphere conditions with concentrated HCl at 90-100оС for 10 to 20 h to solubilize 75-85% of titanium, radioactive, and other acid-soluble components. Concentration of HCl is then lowered by diluting it with 1-5% HCl solution until TiO2 concentration 50-100 g/L. Thermohydrolysis of solution at 100-105оС accompanied by distilling away HCl leads to residual HCl concentration 20-100 g/L. Distilled HCl is sent to processing of perovskite concentrate. Titanium-containing precipitate is separated from mother liquor, washed first with 15-37% HCl solution and then with water to pH 3. Washed precipitate is treated with aluminum acid phosphate with pH 2-4. Aluminum acid phosphate uptake (on conversion to Al2O3) constitutes 0.5 to 5.0% content of TiO2. Treated precipitate is separated and calcined at 850-870оС to give pigment titanium dioxide. From mother liquor (after separation of Ti-containing precipitate), radioactive components are isolated by 4-6-step extraction with tributyl phosphate. Organic phase-to-water phase ratio is (1.5-2.0):1. Degree of titanium recovery is at least 98%, whiteness at least 96.5 conv. units, brightening power 1650-1800 conv. units, spreading capacity 38.0-40.0 g/m2, oil capacity 25-27 g/100 g pigment. Yield of pigment TiO2 is 95.7-98.0%. Amount of radioactive precipitate does not exceed 0.06 kg.
EFFECT: optimized perovskite concentrate processing parameters.
12 cl, 4 ex
FIELD: catalyst preparation methods.
SUBSTANCE: catalyst containing crystalline anatase phase in amount at least 30% and nickel in amount 0.5 to 2% has porous structure with mean pore diameter 2 to 16 nm and specific surface at least 70 m2/g. When used to catalyze photochemical reaction of isolation of hydrogen from water-alcohol mixtures, it provides quantum yield of reaction 0.09-0.13. Preparation of titanium dioxide-based mesoporous material comprises adding titanium tetraalkoxide precursor and organic-nature template to aqueous-organic solvent, ageing reaction mixture to complete formation of spatial structure therefrom through consecutive sol and gel formation stages, separating reaction product, and processing it to remove template. Invention is characterized by that water-alcohol derivative contains no more than 7% water and template consists of at least one ligand selected from group of macrocyclic compounds, in particular oxa- and oxaazamacrocyclic compounds containing at least four oxygen atoms, and/or complexes of indicated macrocyclic compounds with metal ions selected from group of alkali metals or alkali-earth metal metals, or f-metals consisting, in particular, of lithium, potassium, sodium, rubidium, cesium, magnesium, calcium, strontium, barium, lanthanum, and cerium used in amounts from 0.001 to 0.2 mole per 1 mole precursor. Sol is formed by stirring reaction mixture at temperature not higher than 35°C. Once formation of spaced structure completed, mixture is held at the same temperature in open vessel to allow free access of water steam and, when template is removed from the mixture, mixture is first treated with nickel salt solution and then with alkali metal borohydride solution until metallic nickel is formed.
EFFECT: increased sorption and photocatalytic properties of catalyst and enabled reproducibility of its property complex.
7 cl, 68 ex
FIELD: production of inorganic compounds.
SUBSTANCE: invention relates to production of titanium dioxide using chloride process , which is employed in radio-electronic industry to manufacture multiple types of composite ceramic materials and also employed as starting material from production of metal titanates. Synthesis of titanium dioxide having high-purity rutile modification involves thermal hydrolysis of titanium tetrachloride solution with concentration 60-70 g/dm3 TiO2 and containing titanium nuclei and polyacrylamide in amount 100-120 g per 1 kg TiO2 in initial solution. Hydrolysis is continued for 1.5-2 h, after which resulting titanium hydroxide is separated from filtrate, treated with 2-3% oxalic acid solution, then with distilled water, dried and calcined at 550-650°C.
EFFECT: reduced hydrolysis process time, accelerated filtration, reduced consumption of power on heat treatment of resulting precipitate, and reduced negative environmental impact.
1 dwg, 1 tbl, 11 ex
FIELD: chemical industry; methods of production of the catalytic agents of photochemical reaction and sorbents-catalysts of heterogeneous photochemical processes.
SUBSTANCE: the invention is pertaining to the field of chemical industry and may be used in production of the catalytic agents of photochemical reaction and the sorbents-catalysts of heterogeneous photochemical processes of oxidizing of the harmful organic compounds. The precursor in the form of titanium tetraalcoxide and template of the organic nature are introduced into the water-organic dissolvent. The mixture of the reactants is intermixed up to formation of the sol and is kept till the final formation of the special structure. The gained reaction product is separated and treated removal of the template using calcifying or the extraction by the alcohol after preliminary hydrothermal treatment. In preferential version of the invention the water-alcohol dissolvent is additionally introduced with the salt of lanthanum. The invention allows to produce the reproducible sorbent-photocatalyst with the high attributes: the crystal phase of the anatase - no less than 30 mass %, a mean diameter of the pores - 2-16 nanometers, the specific surface - no less than 70 m2/g, does not contain the non-desirable impurities.
EFFECT: the invention ensures production of the reproducible sorbent-photocatalyst with the high attributes of thee crystal phase of the anatase, the effective diameter of the pores, the specific surface at absence of the non-desirable impurities.
7 cl, 68 ex
FIELD: sulfate method of production of titanium dioxide from titanium-containing material.
SUBSTANCE: proposed method includes leaching-out of titanium-containing materials with sulfuric acid solution for obtaining lye, deposition of ferrous sulfate from lye, extraction of titanyl sulfate from lye by means of solvent, hydrolysis of extracted titanyl sulfate followed by roasting of solid phase obtained at hydrolysis stage. At least part of raffinate from extraction stage is used as part of leaching solution at initial leaching-out stage.
EFFECT: high degree of purity of titanium dioxide; reduced amount of acid; reduced power requirements.
20 cl, 2 dwg, 9 tbl, 13 ex
FIELD: industrial inorganic synthesis.
SUBSTANCE: invention relates to a sulfate process for titanium dioxide production from titanium-containing material. Process comprises leaching starting material to produce leaching lye containing acidic solution of titanyl sulfate, which is separated from the lye and then hydrolyzed to form hydrated titanium oxides further fired to produce desired titanium dioxide. Hydrolysis step is properly controlled to form hydrated titanium oxides with desired particle size distribution.
EFFECT: enhanced commercial process efficiency.
29 cl, 2 dwg, 9 tbl, 13 ex
FIELD: sulfate method of production of titanium dioxide from titanium-containing material.
SUBSTANCE: proposed method includes leaching-out of titanium-containing material by sulfuric acid solution, thus obtaining lye containing titanyl sulfate, separation of titanyl sulfate from lye, hydrolysis of titanyl sulfate for forming solid phase containing hydrated titanium oxides followed by roasting the solid phase obtained at the hydrolysis stage. Proposed method includes additional leaching-out stage for leaching-out of solid phase remaining after leaching-out of initial titanium-containing material by means of solution containing sulfuric acid.
EFFECT: enhanced efficiency of process.
24 cl, 2 dwg, 9 tbl, 13 ex
FIELD: light-sensitive catalysts.
SUBSTANCE: invention is directed to preparation of titanium dioxide-based catalysts for photocatalytic treatment of water and air polluted with organics and pathogenic floras. Invention provides a method comprising preparation of reaction solution containing mineral titanium salt, fluoride ion, and activation additive; hydrolysis of mineral titanium salt to form precipitate; washing and calcination of the precipitate. Activation additive utilized is ammonium hydroxide in 5-10% stoichiometric excess. Hydrolysis is conducted for 0.25-0.5 h at pH 10-13, while concentration of fluoride ion in reaction solution is maintained at least 5 wt % based on TiO2. Mineral titanium salt is selected from titanium tetrachloride, titanyl sulfate, and titanium-ammonium chloride.
EFFECT: increased degree of recovering titanium dioxide into target product, increased heat resistance and specific surface of photocatalytic anatase-modification titanium, and reduced process duration.
6 cl, 1 tbl, 14 ex
SUBSTANCE: invention can be applied in production of rutile-structured pigment based on titanium dioxide. The method of obtaining the base for pigment rutile titanium dioxide involves obtaining of source solution containing a titanium compound, addition of effective quantity of a salt catalyst to that solution, preferable addition of a chemical control agent to the solution, solution evaporation for obtaining dry amorphous intermediary product containing a mixture of titanium compounds, and baking of the intermediary product at the temperature under 500°C. Another variant of the method of obtaining the base for pigment rutile titanium dioxide uses eutectic mix of two or more NaCl, KCl and LiCl salts as the salt catalyst, melting temperature of the salt catalyst being lower than baking temperature.
EFFECT: reduction of rutile crystallisation temperature.
42 cl, 12 ex, 19 dwg
SUBSTANCE: invention is related to methods for production of nanosize particles of titanium dioxide, which may be used as photocatalysts, light sensitive materials of sun batteries, photo luminophors, as cathode materials of chemical current sources. Method for production of such particles of titanium dioxide includes hydrolysis of water solution that contains titanium ions, in presence of acid during heating. Water solution containing titanium ions is produced by dissolution of titanium hydride or metal titanium in 37% hydrochloric or 96% sulfuric acid dissolved with water, accordingly, as 1:2 or 1:3.4, to obtain ratio of Ti+3 : Cl-, equal to 1:6, or Ti+3 : SO4 2-, equal to 1:3. Hydrolysis may be performed in presence of nickel chloride or cobalt chloride.
EFFECT: invention makes it possible to simplify production of nanosize particles of titanium dioxide of different shape - in the form of nanobars, nanorods, nanoneedles, without negative effect at environment.
4 dwg, 7 ex