EP1189693A1 - Matieres hybrides sol-gel contenant des metaux nobles utilisees comme catalyseurs pour l'oxydation partielle d'hydrocarbures - Google Patents

Matieres hybrides sol-gel contenant des metaux nobles utilisees comme catalyseurs pour l'oxydation partielle d'hydrocarbures

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Publication number
EP1189693A1
EP1189693A1 EP00936691A EP00936691A EP1189693A1 EP 1189693 A1 EP1189693 A1 EP 1189693A1 EP 00936691 A EP00936691 A EP 00936691A EP 00936691 A EP00936691 A EP 00936691A EP 1189693 A1 EP1189693 A1 EP 1189693A1
Authority
EP
European Patent Office
Prior art keywords
titanium
organic
silicon
gold
catalyst
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP00936691A
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German (de)
English (en)
Inventor
Markus Weisbeck
Christoph Schild
Gerhard Wegener
Georg Wiessmeier
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.)
Covestro Deutschland AG
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Bayer AG
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Publication date
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Publication of EP1189693A1 publication Critical patent/EP1189693A1/fr
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D303/00—Compounds containing three-membered rings having one oxygen atom as the only ring hetero atom
    • C07D303/02—Compounds containing oxirane rings
    • C07D303/04—Compounds containing oxirane rings containing only hydrogen and carbon atoms in addition to the ring oxygen atoms
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/48—Silver or gold
    • B01J23/52—Gold
    • 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
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/036—Precipitation; Co-precipitation to form a gel or a cogel
    • 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
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/27—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation
    • C07C45/32—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen
    • C07C45/33—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties
    • C07C45/34—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D301/00—Preparation of oxiranes
    • C07D301/02—Synthesis of the oxirane ring
    • C07D301/03—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds
    • C07D301/04—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds with air or molecular oxygen
    • C07D301/08—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds with air or molecular oxygen in the gaseous phase
    • C07D301/10—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds with air or molecular oxygen in the gaseous phase with catalysts containing silver or gold

Definitions

  • Sol-gel hybrid materials containing precious metals as catalysts for the partial oxidation of hydrocarbons containing precious metals as catalysts for the partial oxidation of hydrocarbons
  • the present invention relates to a process for the preparation of a composition comprising gold and / or silver particles and an amorphous titanium-silicon mixed oxide, the compositions which can be prepared by this process and their use as a catalyst for the partial oxidation of hydrocarbons.
  • Crystalline titanium silicalite catalysts are known.
  • US-A-4,833,260 describes crystalline titanium silicalite catalysts which are effective in the epoxidation of olefins with the oxidizing agent hydrogen peroxide in the
  • propene oxidation is achieved in low yield (approx. 1-2%) and propene oxide selectivities of 60-70% in the liquid phase through in situ hydrogen peroxide formation with a gas mixture. consisting of molecular oxygen and molecular hydrogen (JP-A-92/352771, WO-97/47386-A1, WO-96/023 023-A1). Hydrogenations occurring as a side reaction lead to larger amounts of propane as a by-product and the fact that it is a liquid phase reaction in which the epoxide formed accumulates in the liquid phase makes these processes of little interest for industrial use.
  • US Pat. No. 5,623,090 describes a gas phase direct oxidation of propene to propene oxide with relatively small propene conversions (0.5-1% propene conversion based on a 10% propene feed concentration), but propene oxide selectivities of> 90% Oxygen described as an oxidizing agent. It is a gold-titanium dioxide-catalyzed gas phase oxidation with molecular oxygen in the presence of hydrogen at temperatures of 40-70 ° C. Commercial crystalline titanium dioxide with predominantly anatase modification (P 25, Degussa; 70% anatase and 30% rutile) is used as the catalyst, which is combined with nanoscale gold particles with a
  • catalysts are used in the same educt gases, in which gold particles on a carrier consisting of finely dispersed titanium centers on a silicon dioxide matrix - analogous to the Shell variant [US-A-3,923,843], a heterogeneous material containing titanium and silicon is used , which is produced by impregnating SiO 2 with titanium precursome in solution (WO-98/000415-A1; WO-98/00414-A1; EP-Al-0 827 779).
  • Another object is to minimize the disadvantages of the prior art method.
  • Another object of the present invention was to provide a technologically simple catalytic gas phase process for the selective oxidation of hydrocarbons with a gaseous oxidizing agent on inexpensive solid catalysts. To provide analyzers, which leads to high yields and low costs with very high selectivities and technically interesting catalyst life.
  • the objects are achieved by the provision of a method for producing a supported composition containing gold and / or silver particles and an amorphous titanium-silicon mixed oxide, characterized in that the titanium-silicon mixed oxide is produced by a sol-gel method, and that organic-inorganic sol-gel hybrid systems are preferably produced, solved.
  • the supported composition that can be produced according to the invention contains gold and / or silver on a carrier material.
  • gold and / or silver is mainly found as an elemental metal (analysis by X-ray absorption spectroscopy). Small amounts of gold and / or silver can also be present in a higher oxidation state. Judging by TEM recording, the largest proportion of the gold and / or silver present is on the surface of the carrier material. These are gold and / or silver clusters on a nanometer scale.
  • Preferred compositions are those in which the gold particles have a diameter in the range from 0.5 nm to 50 nm, preferably 2 to 15 nm and particularly preferably 2.1 to 10 nm.
  • the silver particles preferably have a diameter in the range from 0.5 to 100 nm, preferably 0.5 to 40 nm and particularly preferably 0.5 to 20 nm.
  • the gold concentration should advantageously be in the range of 0.001 to 4% by weight, preferably 0.001 to 2% by weight and particularly preferably 0.005-1.5% by weight of gold.
  • the silver concentration should advantageously be in the range from 0.005 to 20% by weight, preferably 0.01 to 15% by weight and particularly preferably from 0.1 to 10% by weight
  • Amount to silver Gold and / or silver concentrations higher than the ranges mentioned do not result in an increase in the catalytic activity. For economic reasons, the precious metal content should be the minimum amount required to achieve the highest catalyst activity.
  • Titanium-silicon mixed oxide in the sense of the invention generally includes a silicon component which is chemically combined with a titanium component, e.g. Titanium oxide or hydroxide, and possibly other foreign oxides (promoters) is understood. This amorphous titanium-silicon mixed oxide is in contact with a titanium component, e.g. Titanium oxide or hydroxide, and possibly other foreign oxides (promoters) is understood. This amorphous titanium-silicon mixed oxide is in contact with
  • the polarity of the surface of the catalyst according to the invention can optionally be set specifically, e.g. by means of silylating agents and / or by incorporating hydrophobic groups into the carrier matrix (e.g. alkyl and / or aryl groups, or fluorine).
  • the generation of the precious metal particles on the titanium-silicon-containing mixed oxides is not restricted to one method.
  • some example processes such as deposition precipitation (deposition precipitation) as described in EP-B-0 709 360 on page 3, lines 38 ff., Impregnation rank in solution, called incipient wetness, colloid process, sputtering, CVD, PVD.
  • Incipient wetness is understood here to mean the addition of a solution containing soluble gold and / or silver compounds to the carrier material, the volume of the solution on the carrier being less than or equal to the pore volume of the carrier.
  • the carrier thus remains macroscopically dry.
  • All solvents in which the noble metal extender compounds are soluble such as water, alcohols, ethers, esters, acetates, ketones, halogenated hydrocarbons, amines, etc., can be used as solvents for incipient wetness.
  • Preference is given to nanoscale gold particles using the incipient wetness and impregnation methods, nanoscale silver particles using the incipient wetness, impregnation and deposition-precipitation methods.
  • Gold compounds such as tetrachloroauric acid e.g. by the incipient wetness method, also in the presence of oligomeric or polymeric auxiliaries, such as polyvinylpyrolidone, polyvinyl alcohol, polypropylene glycol, polyacrylic acid etc. or in the presence of complexing components such as cyanides, acetylacetone, ethyl acetoacetate, etc.
  • Complex-forming additives such as cyanides, e.g.
  • Alkali or alkaline earth cyanides used.
  • compositions according to the invention can advantageously be further activated before and or after the noble metal coating by thermal treatment at 100-1000 ° C. in various atmospheres such as air, nitrogen, hydrogen, carbon monoxide, carbon dioxide.
  • the activation of the invention is particularly preferably carried out
  • compositions under inert gases in the temperature range of 200-600 ° C.
  • the thermally activated (tempered) compositions according to the invention often show a significantly higher catalytic activity and a longer service life in comparison to known catalysts.
  • the mixed oxides for the purposes of the invention contain, based on silicon oxide, between 0.1 and 20 mol% of titanium, preferably between 0.5 and 10 mol%, particularly preferably between 0.6 and 6 mol%.
  • the titanium is in oxidic form and is preferably chemically incorporated into the mixed oxide via Si-O-Ti bonds or tied up. Active catalysts of this type have only very minor Ti-O-Ti domains.
  • compositions according to the invention can contain further foreign oxides, so-called promoters, from group 5 of the Periodic Table according to IUPAC (1985), such as vanadium, niobium and tantalum, preferably tantalum, group 3, preferably yttrium, group 4, preferably zirconium, the group 8, preferably Fe, of group 15, preferably antimony, of group 13, preferably aluminum, boron, thallium and metals of group 14, preferably germanium
  • promoters from group 5 of the Periodic Table according to IUPAC (1985), such as vanadium, niobium and tantalum, preferably tantalum, group 3, preferably yttrium, group 4, preferably zirconium, the group 8, preferably Fe, of group 15, preferably antimony, of group 13, preferably aluminum, boron, thallium and metals of group 14, preferably germanium
  • the built-in promoters "M” are usually dispersed in the mixed oxide materials and are advantageously bound via element-O-Si bonds.
  • the chemical composition of these materials can be varied over wide ranges.
  • the proportion of the promoter element, based on silicon oxide, is in the range of 0-10 mol%, preferably 0-4 mol%.
  • the promoters are preferably in the form of promoter precursor compounds which are soluble in the respective solvent, such as promoter salts and / or organic promoter compounds, and / or promoter-organic-inorganic compounds used.
  • These promoters can increase both the catalytic activity of the composition and the life of the composition in catalytic oxidation reactions of hydrocarbons.
  • the crystal structure of the silicon component can in principle be chosen as desired, but the amorphous modification is preferred.
  • the crystal structure of the titanium oxide can in principle be selected as desired, but amorphous titanium dioxide modification is preferred.
  • the titanium-silicon mixed oxide does not have to be present as a pure component, but can also be used as a complex material, for example in combination with other oxides. lie (eg titanates). According to our knowledge, the titanium centers, which are chemically bound to silica and / or inorganic silicates, are catalytically active centers.
  • the titanium-containing mixed oxide materials are manufactured using sol-gel processes.
  • Suitable precursor compounds for silicon, titanium and promoter centers are advantageously corresponding low-molecular inorganic mixed compounds suitable for the sol-gel process or preferably a combination of corresponding inorganic and organic-inorganic mixed compounds.
  • low molecular weight means monomeric or oligomeric. If the solubility is sufficient, polymeric precursor compounds of silicon, titanium and promoters are also suitable.
  • the titanium-silicon mixed oxide is produced by simultaneous polymerization of suitable Si and Ti precursors, e.g. co-polycondensation to amorphous xerogels or aerogels or similar (sol-gel process).
  • This sol-gel process is based on the polycondensation of hydrolyzed, colloidally dissolved metal component mixtures (sol) with the formation of an amorphous, three-dimensional network (gel).
  • sol-gel process serves to illustrate this:
  • Preferred solvents for the sol-gel process are alcohols such as isopropanol, butanol, ethanol, methanol or ketones such as acetone, or ethers or chlorinated hydrocarbons.
  • Suitable starting materials are all soluble silicon and titanium compounds of the general formula (I) known to the person skilled in the art, which can serve as starting material for the corresponding oxides or hydroxides,
  • one or more hydrolyzable groups are saturated by terminal and / or bridged (eg CH 3 , C 2 H 5 , C 3 H 7 , ..) or by unsaturated (eg C 2 H 3 , C 6 H) 5 ) R group (s) have been replaced.
  • Polyfunctional organosilanes for example silanols and alkoxides, can also be used.
  • Silanes, organically modified or not, can also be used
  • Presence of di- or multiple alcohols, such as 1,4-butanediol, can be converted to organically modified polysiloxanes.
  • Bridged R groups alkylene radicals
  • Bridged structures such as chain-shaped, star-shaped (branched), cage-shaped or ring-shaped structural elements.
  • Mixed oxides with organic constituents are called organic-inorganic hybrid materials.
  • Organic-inorganic hybrid materials according to the invention contain terminal and / or bridging organic groups in the Ti-Si network. These hybrid materials are preferred for the purposes of the invention.
  • Polysiloxanes such as polydimethylsiloxane (PDMS), possibly with functionalized end groups such as hydroxyl or alkoxy, and / or diphenylsilanediol can also be incorporated homogeneously into the network structure in order to adjust the surface polarity.
  • PDMS polydimethylsiloxane
  • functionalized end groups such as hydroxyl or alkoxy
  • diphenylsilanediol can also be incorporated homogeneously into the network structure in order to adjust the surface polarity.
  • organic-inorganic silicon and titanium extender compounds can also be used in combination with purely inorganic network formers such as tetraethoxysilane, tetramethoxysilane, etc. Instead of monomeric alkoxides, their condensation products can also be used, such as Si (OC2H 5 ) 4 . Furthermore, oligomeric or polymeric systems such as poly (diethoxysiloxane) can also be used.
  • modified silanes used with preference differ significantly from the commonly used purely inorganic network formers such as alkoxysilanes [Si (OR) 4 ] with four hydrolyzable groups, which are used, for example, to produce crystalline framework silicates with a defined pore structure (WO-98 / 00413- A1; TS 1, TS 2, Ti-MCM 41 and 48) can be used.
  • Alkyl means all terminal and / or bridged linear or branched alkyl radicals with 1 to 12 carbon atoms known to the person skilled in the art, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, i-pentyl, neopentyl, hexyl and the other homologues, which in turn can be substituted.
  • Halogen, nitro, or also alkyl, hydroxide or alkoxy, and also cycloalkyl or aryl, such as benzoyl, trimethylphenyl, ethylphenyl, chloromethyl, chloroethyl and nitromethyl, are suitable as substituents.
  • Non-polar substituents such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl and benzoyl are preferably used.
  • organic-inorganic silicon and titanium precursors are suitable, such as gamma-glycidoxypropyltrimethoxysilane, 3,4-epoxycyclohexyl-ethyl-trimethoxysilane, l- (triethoxysilyl) -2- (diethoxymethylsilyl) ethane, tris (gamma-propyl) -trim ) isocyanurate, peralkylated cyclosiloxanes such as hexamethylcyclotrisiloxane, octamethyltetrasiloxane or decamethylpentasiloxane.
  • Polyalkyl (aryl) siloxanes such as polydimethylsiloxane are also suitable.
  • Aryl includes all mononuclear or multinuclear ones known to the skilled worker
  • Halogen nitro or also alkyl or alkoxyl, and also cycloalkyl or aryl, such as bromophenyl, chlorophenyl, toloyl and nitrophenyl. Phenyl, fluorenyl, bromophenyl, chlorophenyl, toloyl and nitrophenyl are preferred.
  • Examples are the corresponding alkoxides, soluble salts, and silicon or titanium organic compounds.
  • alkoxides e.g. Butoxide, isopropoxide, propoxide, ethoxide of these elements are preferred.
  • titanium derivatives such as tetralkoxytitanates, with alkyl groups from C 1 -C 2 such as isobutyl, tert-butyl, n-butyl, i-propyl, propyl, ethyl, etc., or other organic titanium species such as tetrakis (trimethylsilyl) titanate, titanylacetylacetonate, Dicyclopentadienyltitanium dihalide, titanium dihalodialkoxide, titanium halodialkoxide used particularly preferably in combination with titanium compounds containing alkyl groups. Chlorine is preferred for halogen substituents.
  • titanium silsesquioxane of the general formula TiLRySi O ⁇ , where L is an alkyl, cycloalkyl, arylalkyl, alkylaryl, alkoxy, aryloxy, siloxy, amido or a hydroxyl group and R is a cyclopentyl, cyclohexyl or a cycloheptyl group. Titanium isopropoxyheptacyclopentylsilsesquioxane is preferably used.
  • Mixed alkoxides of titanium with other elements such as, for example, titanium triisopropoxy-tri-n-butylstannoxide can also be used.
  • the titanium precursor compounds can also be used in the presence of complex-forming components such as, for example, acetylacetone or ethyl acetoacetate.
  • tetraalkyl orthotitanate is substituted by trialkoxytitanium species, eg trialkoxymethyltitanium
  • the surface polarity can also be adjusted.
  • polymeric systems such as poly (diethoxysiloxane ethyl titanate), poly (octylene glycol titanate), etc. can be used as well.
  • polymeric systems such as e.g.
  • Poly (diethoxysiloxane), poly (diethoxysiloxane-s-butylaluminate), etc. can be used.
  • Co-precipitations or co-gels of Si, Ti and optionally promoters, Si and Ti, Si and optionally promoters, Ti and optionally promoters, or Si and optionally promoters can also be used as starting compounds in the process according to the invention.
  • Water-glass-based processes are also particularly suitable for large-scale technical applications - an aqueous sodium silicate solution is e.g. after ion exchange in
  • Acid hydrolyses or a process in which silica is converted into an organic solvent and then condensed in this medium with either acid, neutral or basic catalysis - preferred starting materials for the purposes of the invention, so that the so-called water glasses are still preferred.
  • polar organic solvents such as alcohols, for example methanol, ethanol, isopropanol, butanol, preferably ethanol, isopropanol or methanol, or other polar organic solvents known to the person skilled in the art, which form the sol gel, are used as solvents - Do not adversely affect the process, such as acetone, sulfolane, or similar solvents, preferably acetone.
  • water glasses water and water-miscible organic solvents, such as alcohols, are used; water is preferably used.
  • compositions according to the invention containing gold and / or silver particles and materials containing titanium and silicon can be in the dried state are approximately described by the following empirical general formula (II) (the residues formed on the surface after modification and any incompletely reacted groups are not taken into account here):
  • SiO x stands for silicon oxide, in the formula Org means the organic constituents formed, preferably in the sol-gel process, from the organic-inorganic precursors, M is a promoter, preferably Ta, Fe, Sb, V, Nb, Zr, Al , B, TI, Y, Ge or combinations thereof, E means gold and / or silver (precious metal) and x, y and z stand for the effectively required number of oxygen to saturate the valences of Si, Ti, and M.
  • M is a promoter, preferably Ta, Fe, Sb, V, Nb, Zr, Al , B, TI, Y, Ge or combinations thereof
  • E means gold and / or silver (precious metal) and x, y and z stand for the effectively required number of oxygen to saturate the valences of Si, Ti, and M.
  • composition (II) described above can be varied over a wide range.
  • the proportion of Org in mole percent can be between 0 and 300%. It is preferably in the range from 10 to 150%, particularly preferably in the range from 30 to 120%.
  • the proportion of titanium oxide, based on silicon oxide is in the range from 0.1 to 10 mol%, preferably in the range from 0.5 to 8.0%, particularly preferably in the range from 2.0 to 7.0%.
  • the proportion of MO z based on silicon oxide is in the range from 0 to 12 mol%.
  • the proportion of E, based on the noble metal-free composition is in the range of 0.001 to 20% by weight. In the case of gold it is preferably in the range from 0.001 to 4% by weight, in the case of silver it is preferably in the range from 0.005 to 20% by weight.
  • compositions according to the invention containing gold and / or silver particles and materials containing titanium and silicon.
  • the catalysts according to the invention can be generated, for example, by simultaneous hydrolysis and / or condensation of Si and Ti precursors, by reacting the organic-inorganic precursor compounds with corresponding Ti compounds with or without subsequent addition of the corresponding Si compounds, or by simultaneously reacting organic-inorganic precursor compounds, corresponding titanium and silicon - Links.
  • the preferred organic-inorganic silicon precursor compound is initially introduced in a solvent, with the addition of a catalyst with a deficit of water, based on the theoretically necessary amount, hydrolyzed, then the titanium compound is added and further water, if appropriate with catalyst, is added. After gel formation, which can take a few minutes to a few days, depending on the composition, the catalyst, the amount of water and the temperature, the gel is dried immediately or after an aging period of up to 30 days or even longer.
  • a catalyst with a deficit of water, based on the theoretically necessary amount, hydrolyzed
  • Condensation reactions one or more treatments of the moist and / or already dried gel with an excess of water or steam. Drying in air or inert gas is preferably carried out between 50 and 250 ° C, particularly preferably between 100 and 180 ° C.
  • the hydrophobicity of the organic-inorganic hybrid materials according to the invention is largely determined by the number and type of terminal and bridging Si-C bonds. Compared to other organic bonds, e.g. Si-O-C bonds, the additional advantage that they are largely chemically inert, d. H. are insensitive to hydrolysis and oxidation reactions.
  • the noble metals can be added in the form of precursor compounds such as salts or organic complexes or compounds during the sol-gel process, or after the gel has been prepared in a known manner, e.g. by
  • Precipitation impregnation in solution, incipient wetness, sputtering, colloids, CVD be applied. If necessary, this step is followed by a surface modification of the composition.
  • DE 199 18 431.3 describes a supported composition containing gold and / or silver particles, titanium oxide and a silicon-containing carrier, which is characterized in that the composition carries groups selected from silicon alkyl, silicon aryl, fluorine-containing alkyl or fluorine-containing aryl groups on the surface, and their use as catalysts for the direct oxidation of hydrocarbons.
  • Organic-inorganic hybrid materials as carriers are not disclosed.
  • modification means in particular the application of groups selected from silicon alkyl, silicon aryl, fluorine-containing alkyl or fluorine-containing aryl groups to the surface of the supported composition, the groups covalently or coordinatively to the functional groups (for example OH groups) be bound on the surface.
  • functional groups for example OH groups
  • Water-based processes are also available for technical applications - an aqueous sodium silicate solution e.g. hydrolyzed in acid after ion exchange, or a process in which silica is converted into an organic solvent and then condensed in this medium with either acid, neutral or basic catalysis - suitable mixed titanium-silicon oxides.
  • aqueous sodium silicate solution e.g. hydrolyzed in acid after ion exchange
  • silica is converted into an organic solvent and then condensed in this medium with either acid, neutral or basic catalysis - suitable mixed titanium-silicon oxides.
  • Acids or bases are used as catalysts for the sol-gel process in the process according to the invention.
  • suitable acids and bases are known to the person skilled in the art from the sol-gel literature, such as L.C. Little, Ann. Rev. Mar. Sci., 15 (1985) 227; S. J. Teichner, G.A. Nicolaon, M.A. Vicarini and G.E.E. Garses, Adv. CoUoid
  • inorganic, aqueous or non-aqueous mineral acids such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid or similar and organic acids such as p-tolylsulfonic acids, formic acid, acetic acid, propionic acid.
  • hydrochloric acid, nitric acid and p-tolylsulfonic acid are particularly preferably used.
  • the quantities used for the starting compounds can be varied over a wide range.
  • Typical molar ratios of hydrolyzable Si (Ti) species to water are in the range of 0.5-32, preferably 0.5-10.
  • Suitable catalyst support materials such as e.g. the fumed silica, such as Aerosile and / or Cab-osile, are suspended or dispersed.
  • Additional condensable, multifunctional molecules e.g. monomeric or polymeric glycols, metal halides, cellulose, methyl cellulose, gelatin or similar compounds can also be used for the targeted “material design”; similar to the hydrolyzed alkoxy metalates, these can be used
  • Integrate polymers homogeneously into the gel network The addition of hydrophobic organic solvents to the sol phase (dispersed phase), e.g. monofunctional aliphatic alcohols with more than eight carbon atoms, causes emulsion formation (dispersed sol phase and homogeneous emulsion liquid) and thus the possibility to further tailor the material.
  • hydrophobic organic solvents e.g. monofunctional aliphatic alcohols with more than eight carbon atoms
  • the process is carried out at pressures in the range from normal pressure to 10 bar, in particular with normal pressure.
  • the process is carried out at temperatures in the range from 0-100 ° C., in particular at 10-60 ° C.
  • the wet gels obtained in the process are dried in a conventional manner, for example by lowering the drainer and / or increasing the temperature.
  • the wet gels are advantageously comminuted into powders before drying. If the aim is not to produce powders, but rather moldings, the sol is converted into appropriate shaping molds before gelling, then gelled and dried. Conventional drying is often associated with the shrinking of the initially uniform gel body through evaporation of the pore liquid. Special drying processes must be used to exchange the pore liquid for air while maintaining the filigree, solid network (aerogels). The most common is the "supercritical
  • the production of the final amorphous, noble metal-containing composition consisting of titanium-silicon mixed oxide and gold and / or silver particles is not limited.
  • the noble metals can be added in the form of leveling compounds, such as salts or organic complexes or compounds, during the sol-gel process, or after the gel has been prepared in a known manner, e.g. applied by impregnation, incipient wetness or precipitation. If appropriate, this step is followed by a surface modification of the composition, in which the surfaces of OH groups are coated with organic residues. Said surface modification can also be carried out after the gel has been produced and before the precious metal has been added.
  • leveling compounds such as salts or organic complexes or compounds
  • compositions according to the invention can have small proportions of crystalline structures.
  • the morphology and particle size of the mixed oxides can be varied over wide ranges, homogeneous, amorphous mixed oxides with high surfaces> 20 m 2 / g, preferably> 50 m 2 / g are particularly preferred.
  • the specific surface is in Usually determined according to Brunauer, Emmet and Teller, J. Anorg. Chem. Soc. 1938, 60, 309, the pore volume by the centrifugation method according to McDaniel, J. Colloid Interface Sei. 1980, 78, 31 and the particle size according to Cornillaut, Appl. Opt. 1972, 11, 265.
  • the sol-gel process offers the possibility of displaying extremely homogeneous and almost completely amorphous titanium-silicon mixed oxides.
  • high titanium contents > 10% by weight, due to the preferred Ti-O-Ti homocondensation, domains are formed in which the octahedral coordination known from pure TiO predominates.
  • dilute systems “TiO 2 in SiO 2 ” ( ⁇ 10% by weight
  • sol-gel process according to the invention is very versatile, since almost all metal, semimetal or
  • Non-metal oxide gels are known and many of them are suitable for the production of xerogels and aerogels, so that the targeted introduction of foreign oxides into the lattice of the titanium-silicon mixed oxides is possible in principle.
  • Catalysis of the oxidation of hydrocarbons can be increased if the catalytically active metal centers are built into a defined pore structure. Side reactions can be suppressed in this way.
  • titanium-silicon mixed oxides which were produced using a homogeneous copolycondensation process, are highly active and selective after precious metal coating - gold and / or silver
  • Oxidation catalysts represent. Especially after a possible treatment of the surface, such systems show technically interesting catalyst service lives of weeks and longer with excellent selectivities.
  • the promoters that may be described are, thanks to the sol-
  • the surface treatment if any, takes place by treatment with organic silylation reagents.
  • the resulting compositions represent excellent, highly selective redox catalysts.
  • silylation reagents e.g. organic silanes, organic silylamines, organic silylamides and their derivatives, organic silazanes, organic siloxanes and other silylating agents and combinations of the silylating reagents can be used.
  • Silylation compounds are expressly also understood to mean partially or perfluorinated alkyl (aryl) silicon-organic compounds.
  • organic silanes are chlorotrimethylsilane, silane Dichlorodimethyl-, Chlorobromdimethylsilan, Nitrotrimethylsilan, chlorotrimethylsilane, methylbutylsilane Ioddi-, chlorodimethylphenylsilane, chlorodimethylsilane, dimethyl-n-propylchlorosilane, Dimethylisopropylchlorsilan, t-butyldimethylchlorosilane, tripropyl chlorosilane, dimethyloctylchlorosilane, tributylchlorosilane, Trihexylchlorosilan, di- methylethylchlorsilan , dimethyloctadecylchlorosilane, n-butyldimethylchlorosilane, bromomethyldimethylchlorosilane, chloromethyldimethylchlorosilane, chlor
  • organic silylamines are N-trimethylsilylimidazole, Nt-butyldimethylsilylimidazole, N-dimethylethylsilylimidazole, N-dimethyl-n-propylsilylimidazole, N-dimethylisopropylsilylimidazol, N-trimethylsilyldimethylsilyl-methylethyl-trimethylsilyl-methyl-trimethyl-n-trimethylsilyl-trimethylsilyl-trimethylsilyl-methyl-trimethyl-n-trimethylsilyl-methyl-n-trimethylsilyl-methyl-n-trimethylsilyl-methyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-trimethyl-n-tri
  • organic silylamides and their derivatives are N, O-bistrimethylsilylacetamide, N, O-bistrimethylsilyltrifluoroacetamide, N-trimethylsilylacetamide, N-methyl-N-trimethylsilylacetamide, N-methyl-N-trimethylsilyltrifluoroacetamide, N-methyl- N-trimethylsilylheptafluorobutyramide, N- (t-butyldimethylsilyl) -N-trifluoroacetamide and N, O-bis (diethylhydrosilyl) trifluoroacetamide.
  • organic silazanes are hexamethyldisilazane, heptamethyldisilazane, 1, 1, 3,3-tetramethyldisilazane, 1,3-bis (chloromethyl) tetramethyldisilazane, 1,3-divinyl-1, 1,3,3-tetramethyldisilazane and 1,3 -Diphenyltetramethyldisilazane.
  • silylation reagents are N-methoxy-N, O-bistrimethylsilyltrifluoroacetamide, N-methoxy-N, O-bistrimethylsilycarbamate, N, O-bistrimethylsilyl sulfamate, trimethylsilyltrifluoromethanesulfonate and N, N'-bistrimethylsilylurea.
  • Preferred silylation reagents are hexamethyldisiloxane, hexamethyldisilazane, chlorotrimethylsilane, N-methyl-N- (trimethylsilyl) -2,2,2-trifluoroacetamide (MSTFA) and combinations of these silylation reagents.
  • compositions which can be prepared according to the invention can also be subjected to a water treatment before the silylation to increase the surfaces of silanol groups.
  • water treatment means that the catalyst with liquid water or an aqueous saturated ammonium chloride solution and / or ammonium nitrate solution and / or ion exchange with polyvalent cations, for example aqueous solutions of, before the silylation process step Ca 2+ , Eu 3+ , is brought into contact, for example the catalyst is suspended in water and subsequently dried (for example at 300 ° C.), or the catalyst is steamed at> 100 ° C., preferably at 150-450 ° C. , treated for 1-6 h.
  • the catalyst is particularly preferably treated with steam at 200-450 ° C. for 2-5 h, then dried and surface-modified.
  • compositions obtainable in the process according to the invention can be used in any physical form for oxidation reactions, e.g. Powders, ground powders, spherical particles, granules (e.g. by spray drying or spray granulation), pellets, extrudates etc.
  • compositions obtainable in the process according to the invention are very well suited in the gas phase in the presence of (air) oxygen and hydrogen or oxygen and gases containing carbon monoxide for the oxidation of hydrocarbons; this use is a further object of the invention.
  • epoxides are selectively obtained from olefins, ketones from saturated secondary hydrocarbons and alcohols from saturated tertiary hydrocarbons.
  • the catalyst service lives are many months and longer.
  • the relative molar ratio of hydrocarbon, oxygen, hydrogen and optionally a diluent gas can be varied over a wide range.
  • the molar amount of the hydrocarbon used in relation to the total number of moles of hydrocarbon, oxygen, hydrogen and diluent gas can be varied within a wide range.
  • the hydrocarbon content is typically greater than 1 mol% and less than 80 mol%. Hydrocarbon contents in the range from 5 to 60 mol% are preferably used, particularly preferably from 10 to 50 mol%.
  • the oxygen can be used in various forms, e.g. molecular oxygen, air and nitrogen oxide. Molecular oxygen is preferred.
  • the molar proportion of oxygen - in relation to the total molar number of hydrocarbon, oxygen, hydrogen and diluent gas - can be varied within a wide range.
  • the oxygen is preferably used in a molar deficit to the hydrocarbon.
  • Oxygen is preferably used in the range of 1-30 mol%, particularly preferably 5-25 mol%.
  • the supported compositions according to the invention show only very little activity and selectivity.
  • Productivity is low up to 180 ° C in the absence of hydrogen; at temperatures above 200 ° C, large quantities of carbon dioxide are formed in addition to partial oxidation products.
  • Any known source of hydrogen can be used, e.g. pure hydrogen, synthesis gas or hydrogen from dehydrogenation of hydrocarbons and alcohols.
  • the hydrogen can also be generated in situ in an upstream reactor, e.g. by dehydrogenation of propane or isobutane or alcohols such as e.g. Isobutanol.
  • Hydrogen can also be used as a complex-bound species, e.g. Catalyst-hydrogen complex to be introduced into the reaction system.
  • the molar proportion of hydrogen - in relation to the total number of moles of hydrocarbon, oxygen, hydrogen and diluent gas - can be varied over a wide range. Typical hydrogen contents are greater than 0.1 mol%, preferably 4-80
  • a diluent gas such as nitrogen, helium, argon, methane, carbon dioxide, carbon monoxide or similar, predominantly inert gases, can optionally also be used in addition to the essential starting gases described above.
  • inert components described can also be used.
  • the addition of inert components is favorable for transporting the heat released by this exothermic oxidation reaction and from a safety point of view.
  • gaseous dilution components such as nitrogen, helium, argon, methane and possibly water vapor and carbon dioxide are preferably used. Water vapor and carbon dioxide are not completely inert, but have a positive effect at very low concentrations ( ⁇ 2% by volume).
  • Diffusion problems of starting materials and products can furthermore be minimized in the catalysts according to the invention by specifically adapting the polarity of the matrix to the requirements of the catalytic reaction.
  • co-condensing agents with non-polar hydrocarbons must be integrated into the polymer.
  • the polarity and swelling behavior of the support can also be advantageously modulated by incorporating oxophilic elements other than silicon such as boron, aluminum, yttrium, tantalum, zircon or titanium. According to the invention, the selection of these heteroatoms is limited to elements which have redox-stable oxidation states.
  • hydrocarbon is understood to mean unsaturated or saturated hydrocarbons such as olefins or alkanes, which can also contain heteroatoms such as N, O, P, S or halogens.
  • the organic component to be oxidized can be acyclic, monocyclic, bicyclic or polycyclic and can be monoolefinic, diolefinic or polyolefinic. With organic Components with two or more double bonds can have the double bonds conjugated and non-conjugated. Hydrocarbons are preferably oxidized, from which those oxidation products are formed whose partial pressure is low enough to remove the product continuously from the catalyst.
  • Another object of the invention is the use of the compositions obtainable in the process according to the invention as catalysts in a liquid phase process for the selective oxidation of hydrocarbons to epoxides in the presence of organic hydroperoxides (R-OOH), hydrogen peroxide or in the presence of oxygen and hydrogen, or oxygen and Gases containing carbon monoxide
  • compositions according to the invention can be produced easily and inexpensively on an industrial scale in terms of process engineering.
  • test instructions Instructions for testing the catalysts (test instructions)
  • a metal tube reactor with an inner diameter of 10 mm and a length of 20 cm is used, which is tempered by means of an oil thermostat.
  • the reactor is supplied with a set of four mass flow controllers (hydrocarbon, oxygen, hydrogen, nitrogen) with feed gases.
  • hydrogen hydrogen
  • feed gases 500 mg of powdered catalyst are placed at 140 ° C and normal pressure.
  • the reactant gases are metered into the reactor from above.
  • the standard catalyst load is 3 1 / (g cat.xh).
  • Propene was selected as an example as the “standard hydrocarbon”.
  • a nitrogen-enriched gas stream hereinafter always referred to as the standard gas composition, was selected to carry out the oxidation reactions: N 2 / H 2 / O 2 / C 3 H 6 : 14/75/5/6%.
  • the reaction gases are analyzed quantitatively by gas chromatography.
  • the gas chromatographic methods hydrogen, oxygen, hydrogen, nitrogen
  • reaction products are separated using a combined FID / TCD method in which three capillary columns are run:
  • FID HP-Innowax, 0.32 mm inner diameter, 60 m long, 0.25 ⁇ m layer thickness:
  • HP-Plot Q 0.32 mm inner diameter, 30 m long, 20 ⁇ m layer thickness
  • HP-Plot Molsieve 5 A 0.32 mm inner diameter, 30 m long, 12 ⁇ m layer thickness:
  • This example describes the preparation of a catalyst consisting of a silicon and titanium-containing, organic-inorganic hybrid material which was coated with gold particles (0.1% by weight) via incipient wetness. Based on silicon, the content of non-hydrolyzable organic components is 68
  • sol-gel material 5.4 g was impregnated with a solution consisting of 540 mg of a 1% strength methanolic gold solution (HAuC x 3 H 2 O; Merck), which was made up to 2.8 g with methanol Macroscopically dry material dried for 4 h at room temperature and then annealed for 2 h at 400 ° C under a nitrogen atmosphere.
  • HuC x 3 H 2 O 1% strength methanolic gold solution
  • This example describes the preparation of a catalyst as in Example 1, but the gold-containing material dried at room temperature is annealed at 400 ° C. for 2 hours under a hydrogen atmosphere.
  • This example describes the preparation of a catalyst consisting of a silicon- and titanium-containing, organic-inorganic hybrid material which was coated with gold particles (0.5% by weight) using the deposition-precipitation method.
  • the gold content of the gold-titanium silicon catalyst is 0.48% by weight (ICP analysis).
  • This example describes the preparation of a purely inorganic catalyst support consisting of the oxides of silicon and titanium, which is coated with gold particles by the precipitation method and subsequently surface-modified.
  • tetraethoxysilane 120 mmol, TEOS, Acros, 98%) are placed in 22.5 ml of i-propanol, mixed, mixed with 2.25 g of 0.1N HCl and stirred for 2 hours. 1.06 g of tetrabutoxytitanium (3.1 mmol, Acros, 98% strength) are added to this solution. dosed dropwise and stirred for 15 min. The homogeneous batch is mixed with 23 ml of 2% aqueous NH 3 solution. The batch reaches the gel point after about 5 minutes, is left to stand for 10 hours and is dried at 120 ° C. for one hour at normal pressure, then for about 20 hours in vacuo (50 mbar) and calcined at 300 ° C. for 3 hours.
  • the gold content of the gold-titanium silicon catalyst is 0.52% by weight (ICP analysis).
  • This example describes the preparation of a catalyst analogously to Example 1, but 60 min after the addition of tetrabutoxytitanium, 220 mg of Al (OC 4 H) 3 (0.9 mmol, Chempur, 99.9% strength) are added to the homogeneous mixture, Stirred for 15 min and gelled as in Example 1, worked up, coated with gold and tempered.
  • Example 7 Comparative example according to EP-Al-827771
  • This example describes the preparation of a purely inorganic catalyst support, consisting of the oxides of silicon and titanium, which is coated with gold particles.
  • the silicon and titanium-containing catalyst carrier is through
  • Aerosil 200 pyrogenic silicon dioxide, Degussa, 200 m 2 / g
  • TiO 2 0.98 g
  • TiO 2 0.98 g
  • the suspension is evaporated to dryness on a rotary evaporator, the solid is then dried at 130 ° C. and calcined at 600 ° C. in an air stream for 3 h.
  • tetrachloroauric acid 0.16 g of tetrachloroauric acid (0.4 mmol, Merck) is dissolved in 500 ml of distilled water, adjusted to pH 8.8 with a 2N sodium hydroxide solution, heated to 70 ° C., mixed with 10 g of the above titanium-containing silica and 1 h stirred. The Solid is filtered off, washed with 30 ml of distilled water, dried at 120 ° C. for 10 hours and calcined in air at 400 ° C. for 3 hours. According to ICP analysis, the catalyst has 0.45% by weight of gold.
  • the catalyst deactivation rank increased with increasing time.
  • Trans-2-butene is selected as the unsaturated hydrocarbon instead of propene.
  • An organic-inorganic hybrid catalyst consisting of the oxides of silicon and titanium, which has been coated with gold particles, is used for the partial oxidation of trans-2-butene.
  • the catalytic preparation is carried out analogously
  • Cyclohexene is chosen as the unsaturated hydrocarbon instead of propene.
  • An organic-inorganic one is used for the partial oxidation of cyclohexene
  • Hybrid catalyst consisting of the oxides of silicon and titanium, which has been coated with gold particles, is used.
  • the catalyst is prepared analogously to Example 1. Cyclohexene is brought into the gas phase using an evaporator. In a test according to the test instructions, constant cyclohexene oxide selectivities of 90% were achieved. The maximum yield of 2.1%, which was reached after 3 h, leveled off to 1.8% after 4 days.
  • 1,3-butadiene is selected as the unsaturated hydrocarbon instead of propene.
  • an organic-inorganic hybrid catalyst consisting of the oxides of silicon and titanium, which has been coated with gold particles, is used. The catalytic preparation is carried out analogously
  • Propane is used as a saturated hydrocarbon instead of propene.
  • an organic-inorganic hybrid catalyst consisting of the oxides of silicon and titanium, which has been coated with gold particles, is used. The catalyst preparation takes place analogously to Example 1.
  • the organic component of the organic-inorganic hybrid materials on the outer and inner surface can for example by so-called DRIFTS Spectroscopy.
  • DRIFTS Diffuse Reflectance Infrared Fourier Transform Spectroscopy
  • Information on the principle of the method and some application examples from the field of heterogeneous catalysis can be found, for example, in
  • DRIFT spectra (OH and CH range) of a gold-containing organic-inorganic hybrid material (according to Example 1) and a gold-containing purely inorganic mixed oxide material. These materials were dried at 200 ° C under inert gas before the DRDFTS analysis. Dashed spectrum: purely inorganic gold, titanium and silicon-containing sol-gel mixed oxide; Solid spectrum: gold, titanium and silicon-containing organic-inorganic sol-gel hybrid material.

Abstract

La présente invention concerne un procédé de production d'une composition contenant des particules d'or et/ou d'argent et un oxyde mixte de titane-silicium amorphe, organique-inorganique. L'invention concerne également les compositions produites selon ce procédé et leur utilisation comme catalyseurs pour l'oxydation sélective d'hydrocarbures en présence d'oxygène moléculaire et d'un agent de réduction.
EP00936691A 1999-04-23 2000-04-11 Matieres hybrides sol-gel contenant des metaux nobles utilisees comme catalyseurs pour l'oxydation partielle d'hydrocarbures Withdrawn EP1189693A1 (fr)

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DE19920753 1999-04-23
DE19920753A DE19920753A1 (de) 1999-04-23 1999-04-23 Verfahren zur Herstellung von amorphen, edelmetallhaltigen Titan-Silizium-Mischoxiden
PCT/EP2000/003214 WO2000064581A1 (fr) 1999-04-23 2000-04-11 Matieres hybrides sol-gel contenant des metaux nobles utilisees comme catalyseurs pour l'oxydation partielle d'hydrocarbures

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Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19959525A1 (de) * 1999-12-09 2001-06-13 Bayer Ag Katalysatoren auf Basis Edelmetall- und Titan-haltiger, organisch-anorganisch Hybridmaterialien zur selektiven Oxidation von Kohlenwasserstoffen
DE10023717A1 (de) * 2000-05-17 2001-11-22 Bayer Ag Formkörper, Verfahren zu dessen Herstellung und Verwendung dieser Formkörper zur selektiven Oxidation von Kohlenwasserstoffen
BR0211796A (pt) 2001-08-01 2004-08-03 Dow Global Technologies Inc Método para aumentar a vida útil de um catalisador de hidro-oxidação
DE10201241A1 (de) 2002-01-15 2003-07-24 Bayer Ag Katalysator
US7081433B2 (en) * 2003-03-12 2006-07-25 The United States Of America As Represented By The Secretary Of The Navy Catalytic three dimensional aerogels having mesoporous nanoarchitecture
GB0411988D0 (en) * 2004-05-28 2004-06-30 British American Tobacco Co Smoking articles and smoking materials
KR100859748B1 (ko) * 2004-12-29 2008-09-24 학교법인 포항공과대학교 불균일계 전이금속 촉매의 제조방법
US8058202B2 (en) 2005-01-04 2011-11-15 3M Innovative Properties Company Heterogeneous, composite, carbonaceous catalyst system and methods that use catalytically active gold
JP2006289341A (ja) * 2005-03-17 2006-10-26 Sumitomo Chemical Co Ltd チタン含有珪素酸化物触媒の保存方法
DE102007019166A1 (de) * 2007-04-20 2008-10-30 Fachhochschule Kiel Verfahren zur Herstellung von Substraten für die Oberflächen-verstärkte Raman-Spektroskopie
US8313773B2 (en) * 2007-06-14 2012-11-20 Board Of Trustees Of The University Of Arkansas Near-infrared responsive carbon nanostructures
US20100194265A1 (en) 2007-07-09 2010-08-05 Katholieke Universiteit Leuven Light-emitting materials for electroluminescent devices
KR100836484B1 (ko) * 2007-11-06 2008-06-10 박혜경 보너스 포인트 거래 및 통합상품구매방법
WO2018062646A2 (fr) * 2016-09-28 2018-04-05 한국과학기술원 Super-réseau de nanoparticules d'or intégré dans de la silice poreuse et procédé de fabrication associé
US10807070B2 (en) * 2017-09-12 2020-10-20 Fuji Xerox Co., Ltd. Silica titania composite aerogel particle, photocatalyst forming composition, and photocatalyst
WO2020220313A1 (fr) * 2019-04-30 2020-11-05 中国科学院大连化学物理研究所 Procédé de préparation d'un catalyseur au carbone supporté, et catalyseur au carbone supporté et son utilisation

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3923843A (en) 1972-03-13 1975-12-02 Shell Oil Co Epoxidation process with improved heterogeneous catalyst
US4176089A (en) * 1978-08-03 1979-11-27 Exxon Research & Engineering Co. Process for the preparation of silica-titania and catalysts comprising the same
IT1127311B (it) 1979-12-21 1986-05-21 Anic Spa Materiale sintetico,cristallino,poroso costituito da ossidi di silicio e titanio,metodo per la sua preparazione e suoi usi
IT1152299B (it) 1982-07-28 1986-12-31 Anic Spa Procedimento per l'espossidazione di composti olefinici
JP3044836B2 (ja) 1991-05-28 2000-05-22 東ソー株式会社 プロピレンオキシドの製法
DE69503142T2 (de) * 1994-09-22 1998-11-05 Hoffmann La Roche Heterogenen katalysatoren
JP2615432B2 (ja) * 1994-10-28 1997-05-28 工業技術院長 金−酸化チタン含有触媒による炭化水素の部分酸化方法
DE19545042A1 (de) * 1995-12-02 1997-06-05 Studiengesellschaft Kohle Mbh Amorphe mikroporöse Mischoxidkatalysatoren mit kontrollierter Oberflächenpolarität für die selektive heterogene Katalyse Adsorption und Stofftrennung
EP0827779A4 (fr) * 1996-03-21 1999-06-30 Agency Ind Science Techn Catalyseurs et procede pour l'oxydation partielle des hydrocarbures
DE19623609A1 (de) 1996-06-13 1997-12-18 Basf Ag Oxidationskatalysator und Verfahren zur Herstellung von Epoxiden aus Olefinen, Wasserstoff und Sauerstoff unter Verwendung des Oxidationskatalysators
CN1152028C (zh) 1996-07-01 2004-06-02 陶氏环球技术公司 烯烃直接氧化成烯烃氧化物的方法
DE19648132A1 (de) 1996-11-21 1998-06-04 Beck & Co Ag Dr Verfahren zur Tränkung von Bauteilen
EP0850936B1 (fr) 1996-12-25 2004-10-27 Agency Of Industrial Science And Technology Procédé pour la préparation d'époxydes et catalyseur à utiliser dans ce procédé
EP1024895B1 (fr) * 1997-06-30 2005-11-30 Dow Global Technologies Inc. Procede pour l'oxydation directe d'olefines en vue d'obtenir des oxydes olefiniques
US6323351B1 (en) 1997-06-30 2001-11-27 The Dow Chemical Company Process for the direct oxidation of olefins to olefin oxides
US6562986B2 (en) 1997-06-30 2003-05-13 Dow Global Technologies, Inc. Process for the direct oxidation of olefins to olefin oxides
DE19757496A1 (de) * 1997-12-23 1999-06-24 Studiengesellschaft Kohle Mbh Hochporöse Photokatalysatoren zur Verwertung von sichtbarem Licht
DE19918431A1 (de) 1999-04-23 2000-10-26 Bayer Ag Verfahren zur Herstellung eines Katalysators zur selektiven Oxidation von Kohlenwasserstoffen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0064581A1 *

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AU5210000A (en) 2000-11-10
CN1347341A (zh) 2002-05-01
BR0009991A (pt) 2002-01-08
HUP0200792A3 (en) 2003-07-28
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