WO2002020407A1 - Poudres d'oxyde metallique nanocristallin, procedes de production et d'application - Google Patents

Poudres d'oxyde metallique nanocristallin, procedes de production et d'application Download PDF

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WO2002020407A1
WO2002020407A1 PCT/IB2001/001639 IB0101639W WO0220407A1 WO 2002020407 A1 WO2002020407 A1 WO 2002020407A1 IB 0101639 W IB0101639 W IB 0101639W WO 0220407 A1 WO0220407 A1 WO 0220407A1
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percent
fact
accordance
metal oxide
content
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PCT/IB2001/001639
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Gerhard Auer
Werner Schuy
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Kerr-Mcgee Pigments Gmbh & Co. Kg
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Application filed by Kerr-Mcgee Pigments Gmbh & Co. Kg filed Critical Kerr-Mcgee Pigments Gmbh & Co. Kg
Priority to KR10-2003-7003555A priority Critical patent/KR20030059133A/ko
Priority to EP01965503A priority patent/EP1317401A1/fr
Priority to JP2002525039A priority patent/JP2004508262A/ja
Priority to AU2001286140A priority patent/AU2001286140A1/en
Publication of WO2002020407A1 publication Critical patent/WO2002020407A1/fr
Priority to NO20031089A priority patent/NO20031089L/no

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    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
    • B01J21/063—Titanium; Oxides or hydroxides thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B82B1/00—Nanostructures formed by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
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    • B82—NANOTECHNOLOGY
    • B82B—NANOSTRUCTURES FORMED BY MANIPULATION OF INDIVIDUAL ATOMS, MOLECULES, OR LIMITED COLLECTIONS OF ATOMS OR MOLECULES AS DISCRETE UNITS; MANUFACTURE OR TREATMENT THEREOF
    • B82B3/00—Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
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Definitions

  • the invention comprises nanocrystalline powdery materials with a TiO 2 content of more than 50 w/w percent, a method for the production of such nanocrystalline powdery materials as well as the application of such nanocrystalline powdery materials.
  • Nanocrystalline metal oxides by which metal oxides with an average diameter of less than 100 mm are understood in the following text, gained several application opportunities in numerous fields in the past years.
  • One of the economically most important fields of application for nanocrystalline metal oxides is their utilisation as a catalyst material, especially in the catalytic decomposition of nitrogen oxides.
  • the method for catalytic destruction of nitrogen oxides in waste gases is described in detail in GB 1 495 396.
  • a gas mixture consisting of nitrogen oxides, oxygen, and ammonia is brought into contact with a catalyst.
  • the catalyst consists predominantly of titanium dioxide and can be produced by several methods, which are described in GB 1 495 396.
  • the components' crystallinity on the one hand and an intimate mixing of the titanium dioxide component with the other components before the final calcination of the catalyst substrate (page 18, lines 17 to 34) on the other hand are of special importance: Both a too coarse-crystalline titanium dioxide component and an insufficient micro-homogeneity have disadvantageous effects on the catalytic characteristics of the catalysts produced thereof.
  • the final calcination of the catalyst substrate is effected by bringing together all components required for a period of several hours, e.g. in a muffle kiln (see examples in GB 1 495 396).
  • a muffle kiln see examples in GB 1 495 396.
  • Various modifications and/or further developments of this method describe the process step of calcination in a similar way, e.g., by usage of a rotary kiln or similar aggregates (EP 268 265 A2, EP 640 386 Al, WO 99/41200).
  • US-A 3,018,186 describes a process, in which a titanium sulphate solution is converted into scaly titanium dioxide (predominantly as a modification of rutile) at temperatures of 800-l,800°C and with a retention time of 0.01-0.5 seconds.
  • the pure titanium sulphate solution used for this process is a material which is not available on a large scale, and is quite expensive in production.
  • the scaly titanium dioxide formed through this process has a diameter of 1 to 20 ⁇ m and is thus not suited for the production of catalysts.
  • US-A 2,397,430 describes a process for the production of titanium dioxide pigments, in which hydrated titanium oxide undergoes calcination at temperatures of approximately 1,000°C and with a retention time of a few minutes.
  • the titanium dioxide obtained this way is characterised by a complete or partial rutile modification and a particle size which is equivalent to the typical size of titanium dioxide pigments, and is thus not suited for the production of catalysts, among others.
  • US-A 5,009,879 describes a process for the production of titanium dioxide, in which the hydrated titanium oxide originating from the conventional sulphate process TiO 2 production undergoes flash calcination at temperatures of 800 to 1,600°C and with a retention time between 0.1 and 60 seconds.
  • the titanium dioxide obtained this way has a BET surface of 1 to 4.5 sqm/g and is thus not suited for the production of catalysts, among others.
  • US-A 5,833,892 describes a flash calcination process of titanium dioxide for the purpose of pigment production, in which the hydrated titanium oxide originating from the conventional sulphate process TiO 2 production, or other titanium-containing compounds such as TiOCl 2 , TiOBr 2 , TiOSO 4 , or hydrolysates of titanium alcoholates are atomised and undergo flash calcination at a temperature between 900 and 1,200°C, with fuels being added if required.
  • the titanium dioxide produced this way has a particle size of 150 to 250 nm (which is equivalent to the typical size of titanium dioxide pigments) and is thus not suited for the production of catalysts, among others.
  • nanocrystalline metal oxides intended for catalyst materials or intermediate products for the production of catalysts, respectively.
  • the production process should be effective and efficient, should ensure a high and constant product quality, and consequently allow flexible and fast control if variations of the educt or product characteristics are required.
  • the task of this invention is, therefore, to provide a nanocrystalline metal oxide powder which allows to form an intermediate product for the production of chemico- technical products, especially of DeNO x catalysts, in a simple and cost-effective way, i.e. without the disadvantages of previous processes.
  • This task is solved by claim 1.
  • the invention thus covers a nanocrystalline metal oxide powder with a TiO 2 content of at least 50 w/w percent to start with and preferably at least 75 w/w percent of TiO 2 , further with an average primary particle size of less than 50 nm and preferably of less than 35 nm, with a BET surface of 25-250 sqm/g, preferably of 50-150 sqm/g and especially preferably of 75-100 sqm/g, with a radiographic anatase percentage of at least 95% and preferably of at least 99%, and with a brightening capacity of 25-70 or preferably of 30-50.
  • Another task was to provide a production method for such nanocrystalline metal oxide powders.
  • the invention thus covers a process for the production of a nanocrystalline metal oxide powder in addition, which is performed with the help of short-time calcination (flash calcination) with an average retention time of the particles within the reactor of less than 120 seconds, or preferably less than 10 seconds, or most preferably less than 2 seconds.
  • the invention covers the application of nanocrystalline metal oxides produced in compliance with the invention, or in a comparable way, as a starting material for the production of chemico-technical products, especially of catalysts, colour pigments, ceramic products, products for electroceramic applications, enamels, welding electrodes, cosmetic products, or UV protectants.
  • a nanocrystalline metal oxide powder produced from traditional starting products by short-time calcination has the characteristics which allow application as a starting material for the production of catalysts, among others, if suitable process parameters are set.
  • flash calcination first the water is vaporised, followed by the calcination step, i.e. by the growth of the primary particles, with a retention time of the particles within the reactor of less than 120 seconds, or preferably of less than 10 seconds, or most preferably of less than 2 seconds.
  • Any apparatus or equipment allowing an average retention time of the calcination material of less than 2 minutes, or preferably of less than 10 seconds, or most preferably of less than 2 seconds can be used as a short-time or flash calcination facility.
  • These include all usual apparatuses the operating parameters of which are suited and which usually work with a direct hot gas supply, such as hot gas atomisation reactors, atomisation roasters, fluid-bed reactors, reaction cyclones, or flash calciners for example. Indirect heating is, however, also possible.
  • Introduction into the reactor may be effected in the form of watery solutions via single-fluid or two-fluid nozzles. Another possibility is to feed the starting material in the form of dried or partially dried materials.
  • the separation of the nanocrystalline metal oxide particles from the gas phase is performed outside the reaction chamber and can be effected by traditional technologies, which the specialist is acquainted with, such as through cyclones and/or electrical or mechanical powder separators.
  • the preferred method is a flash calcination process performed in a directly or indirectly heated reaction chamber, with a gas temperature of 800 to 1,200°C at the reaction chamber's entry and a gas temperature of 500 to 800°C at the reaction chamber's exit.
  • the material to be calcined is preferably fed into the reactor in counterflow to the hot gas, with the material to be calcined being subsequently carried over by the hot gas.
  • the nanocrystalline metal oxide powders obtained this way have good rheologic characteristics: They can well be carried and do not tend to caking.
  • a decisive advantage of the flash calcination technology is that it allows to combine the two process steps of drying and calcination used by traditional technologies, into one single process step.
  • flash calcination technology Another special advantage of the flash calcination technology is that it is possible to react to changes in the educt or product characteristics in a fast and flexible manner, thanks to the short retention times within the reactor. With rotary kilns, which are traditionally used, it may take quite a long time until changes to the process parameters really show an effect on the characteristics of the product obtained. This may lead to quality problems, demand a more personnel-intensive operation, and a larger amount of intermediate products, for example.
  • the suspension obtained is filtered and washed in deionised water in order to reduce the content of undesired dissolved solids such as alkali compounds and SO 4 .
  • the intermediate result is a filter cake.
  • Additives which may be required to achieve the characteristics desired can be added before, during, and after the process steps of filtration or washing, respectively.
  • the suspension of hydrated titanium oxide is preferably only partially neutralised, i.e. in such a manner that the content of sulphate bonded in the filter cake or in the calcined product, respectively, amounts to up to 7 w/w percent, or preferably to 0.5 to 3 w/w percent.
  • a sulphate content of this scale is advantageous to the catalytic characteristics.
  • the filter cake obtained this way is then calcined in compliance with the invention for less than 2 minutes, or preferably for less than 10 seconds, or most preferably for less than 2 seconds.
  • the process in compliance with this invention allows to expose the filter cake directly to flash calcination. It is however also possible to suspend the filter cake first and then to introduce the material obtained this way into the flash calcination facility. Finally, the partially neutralised and washed filter cake can first be completely or partially dried, and then the material obtained this way be introduced into the flash calcination facility.
  • the preferred method is to first mix the filter cake with deionised water in order to obtain a pumpable suspension, then to blind it with specific additives, if required for the application intended, and finally to directly introduce the suspension into one of the aggregates described above, with the help of a nozzle for example, and to expose it to short-time calcination (flash calcination).
  • the advantage of this process variant is that the nanocrystalline metal oxide powder desired is obtained by one single thermal process step, with the suspension allowing to be dosed into the calcination aggregate in an especially simple manner, in contrast to filter cakes.
  • An alternative variant is first to mix the filter cake with deionised water in order to obtain a pumpable suspension, then to blind it with specific additives, if required for the application intended, to completely or partially dry the suspension, and finally to introduce the product obtained into one of the aggregates described above and expose it to short-time calcination (flash calcination).
  • drying aggregates such as spray dryers, spin flash dryers, conveyor dryers, for example, or other devices, which the specialist is acquainted with, may be used.
  • a liquefier is used, pumpable, low-viscosity suspensions with a substantially higher solids content can be produced than without liquefiers, such suspensions allowing substantial energy savings during subsequent drying and/or calcination on the one hand and an increased throughput within the respective aggregate on the other hand.
  • any inorganic or organic compound which increases the electrostatic repulsion of the particles by adsorption on the surface of the hydrated titanium oxide such as hydrochloric acid, polyelectrolytes, or organic acids for example, are suited as liquefiers.
  • the preferred liquefiers to be used are organic compounds, which are degraded during the subsequent process step of calcination without leaving any residues on the nanocrystalline metal oxides.
  • compounds are especially preferred, the decomposition products of which do not contain any other compounds than those usually occurring in burner gases of directly heated calcination facilities.
  • Compounds suited for this purpose are organic acids of the C ⁇ H y O z structure, i.e. in particular carboxylic acids, among which acetic acid and formic acid are preferred most.
  • These compounds allow a distinctly increased solids content of the suspension of hydrated titanium oxide without leaving any residues on the nanocrystalline metal oxides after the calcination step, or any undesired compounds during the gas phase, at a concentration of 0.01 to 5,0 w/w percent, preferably of 0.2 to 2.5 w/w percent already.
  • This increase in the solids content of the suspension of hydrated titanium oxide allows to achieve a throughput at (spray-) drying and/or flash calcination which is increased by more than 100%, and to reduce the energy consumption by over 50%.
  • Such material can also be produced in another way, for example by one of the variants described in GB 1 495 396, such as by hydrolyses of titanium alcoholates or other inorganic or organic titanium compounds.
  • An especially preferable application form of the invention is to add to the hydrated titanium oxide, originating from the conventional sulphate process production of titanium dioxide, a tungsten compound, e. g. ammonium para tungsten, and/or vanadium compounds and/or other compounds which are supportive for catalytic activity, before the process step of flash calcination.
  • the metal oxide powder has a tungsten oxide content (in the form of WO 3 ) of preferably 0 to 20 w/w percent, or especially preferably of 5 to 15 w/w percent.
  • Another especially preferred application form of the invention is to add to the hydrated titanium oxide a silicon and/or aluminium compound and/or other compounds which are supportive for the thermal stability of the catalyst substances produced thereof, before the process step of flash calcination. It is an especially preferred method to add finely dispersed colloidal SiO .
  • the metal oxide powder has an SiO 2 content of preferably 0 to 20 w/w percent, especially preferably of 2 to 8 w/w percent. These compounds may be added before, during, and after the steps of (partial) neutralisation and washing described above. It is also possible first to completely or partially dry the suspension partially neutralised, washed and blended with the compounds stated before, and then to introduce the material obtained this way into the flash calcination facility.
  • the product in compliance with the invention and produced by the method described above has excellent characteristics, especially as a starting material for the production of catalysts.
  • the average particle size of the primary particles (determined on the basis of their BET surface, and on the assumption that the particles have a spherical geometry and a density of 4.2, or established on the basis of electron microscopic photographs, respectively) amounts to approximately 20 nm.
  • the particle size of the primary particles is predominantly determined by the temperature and retention time during calcination.
  • the particle size of the primary particles corresponds to their high specific surface (BET surface), and is a prerequisite for a high activity of the catalysts to be produced from this nanocrystalline powdery material.
  • the BET surface is determined in accordance with DIN 66131 (carrier gas method, single-point method, ratio between carrier gas and adsorptive 90:10, measuring gas nitrogen, adsorption at the temperature of the boiling nitrogen, on the assumption that one nitrogen molecule requires an area of 0.162 nm 2 , pre-treatment: heating in the nitrogen flow at 140°C for 1 hour).
  • a particle size measurement performed with a laser particle analyser delivers an average particle size (mean volume value) of approximately 1 ⁇ m (with conventional ultrasonic dispersion). This value describes solid aggregates, the size of which can essentially be determined by the flocculation structure of the starting product (hydrated titanium oxide), and which allow to be deflocculated by proportionally large forces only, such as by grinding for example.
  • agglomerates in an order of magnitude between 10 and 200 ⁇ m could be detected under the light microscope, the size of which is essentially determined by the kind of their introduction into the flash calcination reactor (e. g. by the type of nozzle). These aggregates or agglomerates, respectively, ensure good processability characteristics of the nanocrystalline metal oxides used as a starting material for catalysts.
  • the tinting strength is determined in accordance with DIN 53192 (with Dataflash 2000 (d/8°), device A of Datacolor).
  • the tinting strength is determined by analysing the values obtained this way, in accordance with DIN 55982.
  • the C/2° (CIE 1931) type of light and standard observer are used.
  • TRONOX® R-KB-2 a commercially available micronised titanium dioxide pigment of Kerr-McGee in the form of the rutile modification, coated by aluminium and silicon compounds and an organic coating, is used as a reference material.
  • the tinting strength of TRONOX® R-KB-2 is defined to be 100.
  • the chemical composition of the nanocrystalline metal oxides allows to adapt them ideally to the requirements profile of the application desired. If the metal oxides are intended to be used as a starting material for catalysts, for example, a residual sulphate content and the addition of e. g. tungsten would be beneficial.
  • An Na, K, and Fe content of less than 1,000 ppm, preferably less than 100 ppm would be as advantageous to the catalytic characteristics.
  • nanocrystalline metal oxides are, however, intended to be used as a starting material for complex mixed oxide pigments, a sulphate content as low as possible and the addition of other elements would be beneficial.
  • the TiO 2 and WO 3 content is determined in accordance with DIN 55912, Part 2, the sulphate content is determined in accordance with DIN 24935, the Na and K content is determined by HF microwave digestion in accordance with DIN 38406, Part 14, and the Fe content is determined in accordance with DIN 51083, Part 6.
  • the titanium dioxide In the absence of any additives (such as W, V, Si, Al for example), the titanium dioxide is completely provided in the form of its anatase modification. If additives as stated above are contained, the titanium dioxide has an anatase-type structure. The anatase modification is more advantageous to the catalytic characteristics, than the rutile modification.
  • the material produced in compliance with the invention and by the method described can be used as a starting material for the production of a wide range of chemico-technical or cosmetico-pharmaceutical products, besides their application as a starting material for the production of catalysts. Thanks to its nanocrystalline structure, the material allows to be used directly or after being conditioned in a suitable manner, if required, for applications requiring titanium dioxide which contains materials that are finely divided to a high degree, such as sun screening agents, or UV absorbers in plastics and coatings for example.
  • nanocrystalline materials produced in compliance with the invention as a starting material for the production of colour pigments, ceramic products, electroceramic applications, enamels, welding electrodes, or other products, with the nanocrystalline structure allowing to be especially well mixed with other components at micro level, and showing an especially high reactivity during subsequent calcination or sintering processes.
  • the nanocrystalline titanium dioxide powders in compliance with the invention for applications the starting material of which would usually be a titanium dioxide with pigment characteristics, i.e. which has an average primary particle size of approximately 0.2 ⁇ m, and is exposed to a calcination step after mixing with other components.
  • This suspension is filtered and washed with deionised water until the Na 2 O content amounts to ⁇ 100 ppm (related to TiO 2 ) and the SO 4 content is 1.5-2% (related to TiO ).
  • the filter cake is then mixed with deionised water until a solids content of 22.8 w/w percent is achieved.
  • the viscosity measured as the run-out time in accordance with DIN 53211, is 13 seconds (with a 4-mm nozzle).
  • the solids content is determined with a commercially available IR dryer.
  • the suspension of hydrated titanium oxide with a solids content of 22.8 w/w percent and a sulphate content of 1.6 w/w percent (related to TiO 2 ) and a BET surface (after drying) of approximately 300 sqm/g is calcined in a high-temperature mixing chamber in an oxidising atmosphere at 700°C (temperature at the mixing chamber's exit) for 0.3 seconds.
  • the suspension is introduced into the high-temperature mixing chamber via a two-fluid nozzle.
  • the product obtained consists predominantly of isometric primary particles of 20 nm, which are predominantly agglomerated to spherulitic particles with an average diameter of 10 to 200 ⁇ m.
  • TiO 2 is stoichiometrically neutralised with NaOH at 80°C. This suspension is filtered and washed with deionised water until the NaO content amounts to ⁇ 100 ppm (related to TiO 2 ) and the SO 4 content is 1.5-2% (related to TiO 2 ). The filter cake with a solids content of 46 w/w percent is then mixed with deionised water and 1.08 w/w percent formic acid (related to TiO 2 ) as a liquefier until a solids content of 37.5 w/w percent is achieved.
  • the viscosity of the 37.5 percent suspension is comparable to the viscosity of the 22.8 percent suspension without any liquefier.
  • the viscosity, measured as the run-out time in accordance with DIN 53211, is
  • the solids content is determined with a commercially available IR dryer.
  • This suspension of hydrated titanium oxide is calcined in a high-temperature mixing chamber in an oxidising atmosphere at 650°C (temperature at the reaction chamber's exit) for 0.3 seconds.
  • the suspension is introduced into the high-temperature mixing chamber via a two-fluid nozzle. No increased organic residues could be detected in the product obtained this way, in comparison with the product of the 1 st example (both products contain less than 0.05 w/w percent of carbon, related to TiO 2 ).
  • This suspension is filtered and washed with deionised water until the NaO content amounts to ⁇ 100 ppm (related to TiO 2 ) and the SO 4 content is 1.5-2% (related to TiO 2 ).
  • the filter cake is then mixed with deionised water, without adding any liquefier, until a solids content of 37.5 w/w percent is achieved.
  • a high viscosity substance is obtained, which does not allow to be pumped or atomised.
  • the viscosity measured as the run-out time in accordance with DIN 53211, cannot be determined as the material does not leave the nozzle at all due to its high viscosity (with a 4-mm nozzle).
  • the solids content is determined with a commercially available IR dryer.
  • a suspension of hydrated titanium oxide as described in the 1 st example (ref. first paragraph) is predried in a spray dryer and then calcined in an electric rotary kiln at approximately 600°C (temperature at the kiln exit).
  • the retention time within the rotary kiln amounts to approximately 4 hours.
  • the product obtained consists predominantly of isometric primary particles of about 20 nm, which are predominantly agglomerated to spherolitic particles with an average diameter of 10 to 200 ⁇ m.

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Abstract

L'invention concerne des matières pulvérulentes nanocristallines dont la teneur en TiO2 est supérieure à 50 % en poids, un procédé de production desdites matières pulvérulentes nanocristallines, ainsi que leur utilisation comme matière première pour la production de produits chimico-techniques ou cosmético-pharmaceutiques, en particulier des catalyseurs, des pigments de couleur, des produits céramiques, des produits destinés à des applications électrocéramiques, des émaux, des électrodes de soudage, des produits cosmétiques, ou des produits de protection contre les UV.
PCT/IB2001/001639 2000-09-11 2001-09-11 Poudres d'oxyde metallique nanocristallin, procedes de production et d'application WO2002020407A1 (fr)

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Application Number Priority Date Filing Date Title
KR10-2003-7003555A KR20030059133A (ko) 2000-09-11 2001-09-11 나노 결정립 금속 산화물 분말 및 그 제조 방법
EP01965503A EP1317401A1 (fr) 2000-09-11 2001-09-11 Poudres d'oxyde metallique nanocristallin, procedes de production et d'application
JP2002525039A JP2004508262A (ja) 2000-09-11 2001-09-11 ナノ結晶質金属酸化物粉末の製造法及び施用法
AU2001286140A AU2001286140A1 (en) 2000-09-11 2001-09-11 Nanocrystalline metal oxide powders-production and application methods
NO20031089A NO20031089L (no) 2000-09-11 2003-03-10 Nanokrystallinsk metalloksidpulver og fremgangsmåte for fremstilling av dette

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DE10044986A DE10044986A1 (de) 2000-09-11 2000-09-11 Nanokristallines Metalloxidpulver, Verfahren zu seiner Herstellung und Verwendung
DE10044986.7 2000-09-11

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WO2007074436A1 (fr) * 2005-12-27 2007-07-05 Joma International As Procedes de production de particules d'oxyde de titane, et particules et preparations ainsi obtenues
CN102523735A (zh) * 2009-07-31 2012-06-27 美礼联无机化工公司 二氧化硅稳定化的超细锐钛矿二氧化钛、氧化钒催化剂及其生产方法
CN102812094A (zh) * 2010-04-06 2012-12-05 赢创德固赛有限公司 包含二氧化硅和二氧化钛的颗粒
US8900536B2 (en) 2012-08-24 2014-12-02 Cristal Usa Inc. Catalyst support materials, catalysts, methods of making them and uses thereof
CN113804525A (zh) * 2021-09-01 2021-12-17 山西钢科碳材料有限公司 一种纤维样品的前处理方法

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DE10261287A1 (de) * 2002-12-27 2004-07-15 Sustech Gmbh & Co. Kg Titan(IV)oxid-Material
DE10261286A1 (de) * 2002-12-27 2004-07-15 Sustech Gmbh & Co. Kg Verwendung eines teilchenförmigen Titan(IV)oxid-Materials als Elektrodenmaterial in Batterien
DE102004027549A1 (de) * 2004-04-07 2005-10-27 Kronos International, Inc. Kohlenstoffhaltiger Titandioxid-Photokatalysator und Verfahren zu seiner Herstellung
DE102006029284A1 (de) * 2006-06-23 2007-12-27 Kronos International, Inc. Verfahren zur Identifizierung und Verifizierung von Titandioxid-Pigmentpartikel enthaltenden Produkten
DE102011017090B3 (de) * 2011-04-14 2012-08-30 Kronos International Inc. Verfahren zur Herstellung eines Photokatalysators auf Basis von Titandioxid

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JPH09302138A (ja) * 1996-05-09 1997-11-25 Kao Corp 高吸水性樹脂組成物
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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007074436A1 (fr) * 2005-12-27 2007-07-05 Joma International As Procedes de production de particules d'oxyde de titane, et particules et preparations ainsi obtenues
US7763232B2 (en) 2005-12-27 2010-07-27 Joma International As Methods for production of titanium oxide particles, and particles and preparations produced thereby
CN102523735A (zh) * 2009-07-31 2012-06-27 美礼联无机化工公司 二氧化硅稳定化的超细锐钛矿二氧化钛、氧化钒催化剂及其生产方法
US8545796B2 (en) 2009-07-31 2013-10-01 Cristal Usa Inc. Silica-stabilized ultrafine anatase titania, vanadia catalysts, and methods of production thereof
AU2010277226B2 (en) * 2009-07-31 2015-02-05 Tronox Llc Silica-stabilized ultrafine anatase titania, vanadia catalysts, and methods of production thereof
US9421519B2 (en) 2009-07-31 2016-08-23 Cristal USA, Inc. Silica-stabilized ultrafine anatase titania, vanadia catalysts, and methods of production thereof
EP2459310B1 (fr) 2009-07-31 2021-12-15 Tronox LLC Catalyseurs ultrafins à l oxyde de vanadium et au dioxyde de titane anatase stabilisés par de la silice, et leurs procédés de production
CN102812094A (zh) * 2010-04-06 2012-12-05 赢创德固赛有限公司 包含二氧化硅和二氧化钛的颗粒
US8900536B2 (en) 2012-08-24 2014-12-02 Cristal Usa Inc. Catalyst support materials, catalysts, methods of making them and uses thereof
US9108185B2 (en) 2012-08-24 2015-08-18 Cristal Usa Inc. Catalyst support materials, catalysts, methods of making them and uses thereof
CN113804525A (zh) * 2021-09-01 2021-12-17 山西钢科碳材料有限公司 一种纤维样品的前处理方法
CN113804525B (zh) * 2021-09-01 2024-04-19 山西钢科碳材料有限公司 一种纤维样品的前处理方法

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NO20031089D0 (no) 2003-03-10
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DE10044986A1 (de) 2002-03-21
AU2001286140A1 (en) 2002-03-22
EP1317401A1 (fr) 2003-06-11
NO20031089L (no) 2003-03-10

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