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WO2002034842A1 - Oxydes et hydroxydes metalliques munis d'un revetement - Google Patents

Oxydes et hydroxydes metalliques munis d'un revetement Download PDF

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Publication number
WO2002034842A1
WO2002034842A1 PCT/GB2001/004777 GB0104777W WO0234842A1 WO 2002034842 A1 WO2002034842 A1 WO 2002034842A1 GB 0104777 W GB0104777 W GB 0104777W WO 0234842 A1 WO0234842 A1 WO 0234842A1
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Prior art keywords
oxide
particle according
solvent
salt
lewis base
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Ceased
Application number
PCT/GB2001/004777
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English (en)
Inventor
Mark Green
Gareth Wakefield
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Oxonica Ltd
Original Assignee
Oxonica Ltd
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Filing date
Publication date
Priority claimed from GB0026341A external-priority patent/GB0026341D0/en
Priority claimed from GB0102449A external-priority patent/GB0102449D0/en
Application filed by Oxonica Ltd filed Critical Oxonica Ltd
Priority to AU2002210729A priority Critical patent/AU2002210729A1/en
Publication of WO2002034842A1 publication Critical patent/WO2002034842A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F17/00—Compounds of rare earth metals
    • C01F17/20—Compounds containing only rare earth metals as the metal element
    • C01F17/206—Compounds containing only rare earth metals as the metal element oxide or hydroxide being the only anion
    • C01F17/224—Oxides or hydroxides of lanthanides
    • C01F17/235—Cerium oxides or hydroxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • 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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
    • C01B13/14—Methods for preparing oxides or hydroxides in general
    • C01B13/145—After-treatment of oxides or hydroxides, e.g. pulverising, drying, decreasing the acidity
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/08—Treatment with low-molecular-weight non-polymer organic compounds
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/01—Crystal-structural characteristics depicted by a TEM-image
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
    • C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
    • C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
    • C01P2004/86—Thin layer coatings, i.e. the coating thickness being less than 0.1 time the particle radius
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/22—Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/12—Inorganic compounds
    • C10L1/1233—Inorganic compounds oxygen containing compounds, e.g. oxides, hydroxides, acids and salts thereof
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/16—Hydrocarbons
    • C10L1/1608—Well defined compounds, e.g. hexane, benzene
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/182—Organic compounds containing oxygen containing hydroxy groups; Salts thereof
    • C10L1/1822—Organic compounds containing oxygen containing hydroxy groups; Salts thereof hydroxy group directly attached to (cyclo)aliphatic carbon atoms
    • C10L1/1824—Organic compounds containing oxygen containing hydroxy groups; Salts thereof hydroxy group directly attached to (cyclo)aliphatic carbon atoms mono-hydroxy
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/188—Carboxylic acids; metal salts thereof
    • C10L1/1881—Carboxylic acids; metal salts thereof carboxylic group attached to an aliphatic carbon atom
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/19—Esters ester radical containing compounds; ester ethers; carbonic acid esters
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/26—Organic compounds containing phosphorus
    • C10L1/2608—Organic compounds containing phosphorus containing a phosphorus-carbon bond

Definitions

  • cerium oxide acts as a catalyst in automotive exhaust systems. Cerium oxide releases oxygen and is therefore capable of regulating the oxygen partial pressure in the exhaust system. With the engine working under lean conditions, cerium oxide removes excess oxygen from the exhaust gas and, catalysed by, for example, platinum, NO x is reduced to nitrogen. During rich cycles, cerium oxide releases oxygen to oxidise carbon monoxide to carbon dioxide. It is believed that cerium oxide acts catalytically. As such, the magnitude of the effect should be directly related to the surface area of the particles.
  • the particles are as small as possible.
  • a cerium oxide readily available, especially as very small particles, to catalyst systems and this can be achieved most easily by incorporating the cerium oxide into the fuel i.e. as a fuel additive.
  • the cerium oxide needs to be dispersible or soluble in the fuel.
  • the present invention is aimed at rendering metal oxides and hydroxides soluble or dispersible in organic solvents.
  • a nanoparticle of an oxide or hydroxide of one or more metals and/or metalloids which possesses a hydrophobic coating of an organic acid or anhydride or ester or Lewis base.
  • cerium oxide Apart from cerium oxide, the present invention is applicable to other rare earth oxides and indeed other metal oxides and hydroxides including metals of Group II of the periodic table such as magnesium, calcium, strontium and barium, aluminium, zirconium e.g. Zr0 2 , titanium e.g. TiO 2 , nickel e.g. NiO, and iron as Fe 2 0 3 and Fe 3 0 4 and other transition metals as well as lanthanide and actinide metal oxides and metalloid oxides and hydroxides such as those of silicon. Particles of mixed oxides and hydroxides such as a mixture of cerium oxide and zirconium oxide can also be produced in according with the invention.
  • metals of Group II of the periodic table such as magnesium, calcium, strontium and barium, aluminium, zirconium e.g. Zr0 2 , titanium e.g. TiO 2 , nickel e.g. NiO, and iron as Fe 2 0 3 and Fe 3 0 4 and other transition
  • the coating (or capping) agents are generally Lewis bases or an organic carboxylic acid or anhydride which typically possesses at least 8 carbon atoms, e.g. 10 to 25 carbon atoms, especially 12 to 16 or 18 carbon atoms, especially lauric acid. It will be appreciated that the carbon chain can be saturated or unsaturated, for example ethylenically unsaturated as in oleic acid. Similar comments apply to the anhydrides which can be used. A preferred anhydride is dodecylsuccinic anhydride.
  • Other organic acids, anhydrides and esters which can be used in the process of the present invention include those derived from phosphoric acid and sulphonic acid.
  • the esters are typically aliphatic esters, for example alkyl esters where both the acid and ester parts have 4 to 18 carbon atoms.
  • Suitable Lewis bases generally possess an aliphatic chain of at least 8 carbon atoms and include mercapto compounds, phosphines, phosphine oxides and amines as well as long chain ethers, diols, esters and aldehydes.
  • Polymeric materials including dendrimers can also be used provided that they possess a hydrophobic chain of at least 8 carbon atoms and one or more Lewis base groups, as well as mixtures of two or more such acids and/or Lewis bases.
  • Typical polar Lewis bases include trialkylphosphine oxides P(R 3 ) 3 0, including trioctyl phosphine oxide (TOPO), which is particularly preferred, trialkylphosphines, P(R 3 ) 3 , amines N(R 3 ) 3 , thiocompounds S(R 3 ) 2 and carboxylic acids or esters R 3 COOR 4 and mixtures thereof, wherein each R 3 , which may be identical or different, is selected from C,_ 24 alkyl groups, C 2 . 24 alkenyl groups, alkoxy groups of formula -0(C,.
  • TOPO trioctyl phosphine oxide
  • R 4 is selected from hydrogen and C t . 2 alkyl groups, preferably hydrogen and C L H alkyl groups.
  • Typical examples of ., 4 and C,. 4 alkyl groups, C 2 . 24 alkenyl groups, aryl groups and heterocyclic groups are described below.
  • polar Lewis base capping ligand a polymer, including dendrimers, containing an electron rich group such as a polymer containing one or more of the moieties P(R 3 ) 3 0, P(R 3 ) 3 , N(R 3 ) 3 , S(R 3 ) 2 or R 3 COOR 4 , wherein R 3 and R 4 are as defined above; or a mixture of Lewis bases such as a mixture of two or more of the compounds or polymers mentioned above.
  • alkyl group is an alkyl group as defined above which contains from 1 to 4 carbon atoms.
  • C alkyl groups include methyl, ethyl, i-propyl, n-propyl, n-butyl and tert-butyl.
  • a C 2 . 24 alkenyl group is a linear or branched alkenyl group which may be unsubstituted or substituted at any position and which may contain heteroatoms selected from P, N, 0 and S. Typically, it is unsubstituted or carries one or two substituents.
  • Suitable substituents include halogen, hydroxyl, cyano, -NR 2 , nitro, oxo, -CO 2 R, -SOR and -S0 2 R wherein each R may be identical or different and is selected from hydrogen or C alkyl.
  • an aryl group is typically a C 6 . 10 aryl group such as phenyl or naphthyl, preferably phenyl.
  • An aryl group may be unsubstituted or substituted at any position, with one or more substituents. Typically, it is unsubstituted or carries one or two substituents. Suitable substituents include halogen, C 1 alkyl, C,_ 4 alkenyl, each of which may be substituted by one or more halogens, hydroxyl, cyano, -NR 2 , nitro, oxo, -CO 2 R, -SOR and-SO 2 R wherein each R may be identical or different and is selected from hydrogen and C l alkyl.
  • a heterocyclic group is a 5- to 10- membered ring containing one or more heteroatoms selected from N, O and S. Typical examples include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, furanyl, thienyl, pyrazolidinyl, pyrrolyl and pyrazolyl groups.
  • a heterocyclic group may be substituted or unsubstituted at any position, with one or more substituents. Typically, a heterocyclic group is unsubstituted or substituted by one or two substituents.
  • Suitable substituents include halogen, C M alkyl, C, .4 alkenyl, each of which may be substituted by one or more halogens, hydroxyl, cyano, -NR 2 , nitro, oxo, -C0 2 R, -SOR and-S0 2 R wherein each R may be identical or different and is selected from hydrogen and C 4 alkyl.
  • halogen is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine.
  • the particles of the present invention can be prepared in more than one way but preferably by heating a decomposable salt of the metal (or metalloid) in the presence of a capping agent which is a solvent for the salt to a temperature sufficient to convert the salt to the corresponding oxide and causing the oxide to precipitate by the addition of a non-solvent therefor.
  • a capping agent which is a solvent for the salt
  • Suitable salts generally include nitrates and carbonates, depending on the particular metal.
  • the process is conducted at a sufficient temperature to ensure the conversion of the salt to the oxide. In some instances, this will involve a change of charge on the metal ion.
  • Ce(N0 3 ) 3 contains Ce 3+ and this has to be converted to Ce 4+ for the oxide.
  • a temperature of 120° C to 220 °C is typical eg. 130°C to 205°C.
  • this process of the present invention can be carried out in two ways. Either the process is carried out with the capping agent acting as solvent and reaction medium (which is therefore present in excess) and the metal salt is dissolved in a solvent which is miscible with the capping agent. Alternatively, the salt and the capping agent are mixed together in a mutual solvent.
  • the metal salt is typically dissolved in a solvent therefor and then injected into the capping agent which may have already been heated.
  • Typical solvents include aromatic solvents, for example heterocyclic compounds such as pyridine. It is desirable that the solvent also acts as a Lewis base such as 4- tert-butyl-pyridine.
  • Other solvents which can be used include aliphatic alcohols, typically of 2 to 4 or 6 carbon atoms such as 1,4-butanediol.
  • metal salt and capping agent are mixed together, for example from 10: 1 to 1 : 10, especially from 2:1 to 1 : 10, particularly about 1 : 1.
  • An excess of the solvent typically an aliphatic alcohol, for example having 2 to 4 or 6 carbon atoms such as 1 ,3-butanediol, is used.
  • the molar ratio of solvent to metal salt is at least 50: 1, especially 50: 1 to 500: 1 , preferably 75:1 to 150: 1 , typically about 100: 1. If the concentration of metal salt is too high, the particle size increases and this makes dispersion more difficult.
  • Methanol can be used to cause the oxide to come out of solution in the capping agent or in the alcohol. The resulting particles can then be recovered.
  • Suitable solvent/non-solvent combinations for this purpose include toluene/methanol, hexane/ethanol, chloroform/methanol, pyridine/hexane and butanol/methanol.
  • the capping agent prevents the particle size from increasing. In this way it is possible to obtain particle over a wide range of sizes up to, say 40nm or 50nm.
  • the particles of the present invention are nanometer sized, in general having a size not exceeding lOOnm. Typically they are from 2 or 3nm to 50nm, for example not exceeding lOnm. It will be appreciated that the actual size of the particles is less important than their ability to be dispersible.
  • the resulting particles are generally fully dispersible in common solvents including aromatic solvents, aliphatic hydrocarbons and aliphatic alcohols such as those listed above.
  • the coated metal (or metalloid) oxides and hydroxides can also readily be obtained by dispersing particles of the material in water, adding the coating agent in an organic solvent therefor to it and then mixing the materials sufficiently to cause a phase transfer to occur.
  • the organic solvent will be the solvent for which the particles are destined eg petrol or, for example, an aromatic hydrocarbon such as toluene.
  • the amount of capping agent used is not critical provided there is sufficient to coat the particles. Thus an equimolar amount of capping agent or less is generally used.
  • the present invention is particularly applicable to nanometer sized particles, in general particles having a size not exceeding 100 nm, typically 10 to 25 nm.
  • the capping agents which can be used in the present invention are capable of reacting with the metal oxide or hydroxide. It is l ⁇ iown that cerium oxide, for example, possesses hydroxy groups on the surface (see, for example, J. Chem. Soc. Faraday T92: (23) 4669-4673, December 1996) and it is believed that these react with the acid grouping leaving the long chain, lipophilic, portion of the molecule pointing into the solvent. It should be added that the presence of these- hydroxy groups means that the particles are easily dispersed in water but this, of course, in itself makes them less readily dispersible in an organic solvent.
  • the particle By incorporating a long chain in the surface, the particle becomes lipophilic and therefore more susceptible to dissolution in organic media.
  • Particles of cerium oxide obtained by the process of the present invention are particularly useful as fuel additives since they are fully dispersible in common solvents, diesel fuel and petrol.
  • Example 1 Commercially available CeO 2 (0.5g., 2.9 mmol) was dispersed in 100 ml de- ionised water. In a separate flask, a carboxylic acid namely stearic acid, 0.81 g, 3.84 mmol was dissolved in 100 ml toluene. The two solutions were mixed together and an immediate phase transfer occurred. The mixture was mixed vigorously for two hours. The resulting white powder was then isolated by centrifugation. The powder could then be dispersed in organic solvents such as toluene.
  • TOPO trioctyl phosphine oxide
  • 6I-LO is dissolved in a 5ml 4-t butyl pyridine and injected into the TOPO. An immediate reaction takes place.
  • Figure 1 is an electronmicrograph of the resulting particles.
  • Example 3 (i) 4.72g Ce(NO 3 ) 3 6H 2 0 and 4.76g pure TOPO are mixed in 100ml 1 ,4- butanediol overnight in air (mole ratio 1 : 1 :100). This produced an opaque mixture after 18 hours stirring.
  • Example 2 The samples of Examples 2 and 3 have been confirmed to be the cubic phase of Ce0 2 by electron microscopy and electron diffraction.
  • the particles of Example 2 are essentially cubes below 4nm in size while those of Example 3 which are below lOnm in size are spherical.

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  • Oil, Petroleum & Natural Gas (AREA)
  • Life Sciences & Earth Sciences (AREA)
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  • Condensed Matter Physics & Semiconductors (AREA)
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  • Crystallography & Structural Chemistry (AREA)
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  • General Chemical & Material Sciences (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

La présente invention concerne un procédé de préparation de nanoparticules d'oxyde ou d'hydroxyde de métal ou de métalloïde selon lequel on chauffe un sel décomposable du métal en présence d'un agent de capsulage qui est un solvant pour le sel à une température suffisante pour transformer le sel en l'oxyde correspondant, et on provoque la précipitation de l'oxyde en ajoutant un non solvant de ce dernier. L'invention se rapporte également à des nanoparticules d'oxyde ou d'hydroxyde d'un ou plusieurs métaux et/ou métalloïdes comprenant un revêtement hydrophobe d'un acide ou anhydride organique ou d'un ester ou d'une base de Lewis.
PCT/GB2001/004777 2000-10-27 2001-10-29 Oxydes et hydroxydes metalliques munis d'un revetement Ceased WO2002034842A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002210729A AU2002210729A1 (en) 2000-10-27 2001-10-29 Coated metal oxides and hydroxides

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB0026341A GB0026341D0 (en) 2000-10-27 2000-10-27 Coated metal oxides and hydroxides
GB0026341.8 2000-10-27
GB0102449.6 2001-01-31
GB0102449A GB0102449D0 (en) 2001-01-31 2001-01-31 Metal oxide nanoparticles

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002092703A1 (fr) * 2001-05-16 2002-11-21 Oxonica Limited Fragmentation d'oxydes et d'hydroxydes de metal enrobes
WO2007064301A1 (fr) * 2005-11-30 2007-06-07 Agency For Science, Technology And Research Nanoparticule et procedes associes
CN109971413A (zh) * 2019-02-26 2019-07-05 北京化工大学 一种高折射率led封装胶材料的制备方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB871411A (en) * 1959-03-13 1961-06-28 Micafine Ltd Methods of increasing the dispersibility of mica in powder form
EP0097563A1 (fr) * 1982-06-11 1984-01-04 Rhone-Poulenc Specialites Chimiques Procédé de préparation de dispersions colloidales de dioxyde cérique dans des liquides organiques
WO1998045212A1 (fr) * 1997-04-04 1998-10-15 Rhodia Rare Earths Inc. OXYDES DE CERIUM, OXYDES DE ZIRCONIUM, OXYDES MIXTES Ce/Zr ET SOLUTIONS SOLIDES Ce/Zr PRESENTANT UNE STABILITE THERMIQUE ET UNE CAPACITE DE STOCKAGE D'OXYGENE AMELIOREES
WO1999046204A1 (fr) * 1998-02-09 1999-09-16 Isis Innovation Limited Nanoparticules autoactivees, d'oxydes de terres rares

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB871411A (en) * 1959-03-13 1961-06-28 Micafine Ltd Methods of increasing the dispersibility of mica in powder form
EP0097563A1 (fr) * 1982-06-11 1984-01-04 Rhone-Poulenc Specialites Chimiques Procédé de préparation de dispersions colloidales de dioxyde cérique dans des liquides organiques
WO1998045212A1 (fr) * 1997-04-04 1998-10-15 Rhodia Rare Earths Inc. OXYDES DE CERIUM, OXYDES DE ZIRCONIUM, OXYDES MIXTES Ce/Zr ET SOLUTIONS SOLIDES Ce/Zr PRESENTANT UNE STABILITE THERMIQUE ET UNE CAPACITE DE STOCKAGE D'OXYGENE AMELIOREES
WO1999046204A1 (fr) * 1998-02-09 1999-09-16 Isis Innovation Limited Nanoparticules autoactivees, d'oxydes de terres rares

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002092703A1 (fr) * 2001-05-16 2002-11-21 Oxonica Limited Fragmentation d'oxydes et d'hydroxydes de metal enrobes
WO2007064301A1 (fr) * 2005-11-30 2007-06-07 Agency For Science, Technology And Research Nanoparticule et procedes associes
CN109971413A (zh) * 2019-02-26 2019-07-05 北京化工大学 一种高折射率led封装胶材料的制备方法

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