Abstract: Methods for synthesizing a water-soluble titanium-silicon complex are disclosed herein. The titanium-silicon complex can be utilized to produce titanated solid oxide supports and titanated chromium supported catalysts. The titanated chromium supported catalysts subsequently can be used to polymerize olefins to produce, for example, ethylene based homopolymer and copolymers.

Abstract: A hydrogel comprising water, and a plurality of titanium-silica-chromium nanoparticle agglomerates, wherein each titanium-silica-chromium nanoparticle agglomerate is an agglomeration of titanium-silica-chromium nanoparticles, the agglomerates having an average titanium penetration depth designated x with a coefficient of variation for the average titanium penetration depth of less than about 1.0 wherein a silica content of the hydrogel is of from about 10 wt. % to about 35 wt. % based on a total weight of the hydrogel.

Abstract: A hydrolysis method for tert-butyl ester in gadolinium-based contrast agent comprises hydrolyzing the tert-butyl ester with a catalyst. The preparation method of the catalyst comprises the following steps: subjecting zirconia and titanium tetrachloride to reaction in the presence of sulfuric acid and water at 60° C. to 90° C. until solids are dissolved, adding silica to perform reaction for 1 to 5 h, filtering to obtain solids, washing and calcining the solids. This hydrolysis method does not introduce other substances that are difficult to remove, such as acids, and provides high hydrolysis efficiency and high purity of the obtained product.

Abstract: Methods of simultaneously converting butanes and methanol to olefins over Ti-containing zeolite catalysts are described. The exothermicity of the alcohols to olefins reaction is matched by endothermicity of dehydrogenation reaction of butane(s) to light olefins resulting in a thermo-neutral process. The Ti-containing zeolites provide excellent selectivity to light olefins as well as exceptionally high hydrothermal stability. The coupled reaction may advantageously be conducted in a staged reactor with methanol/DME conversion zones alternating with zones for butane(s) dehydrogenation. The resulting light olefins can then be reacted with iso-butane to produce high-octane alkylate. The net result is a highly efficient and low cost method for converting methanol and butanes to alkylate.

Abstract: A hydrogel comprising water, and a plurality of titanium-silica-chromium nanoparticle agglomerates, wherein each titanium-silica-chromium nanoparticle agglomerate is an agglomeration of titanium-silica-chromium nanoparticles, the agglomerates having an average titanium penetration depth designated x with a coefficient of variation for the average titanium penetration depth of less than about 1.0 wherein a silica content of the hydrogel is of from about 10 wt. % to about 35 wt. % based on a total weight of the hydrogel.

Abstract: A silica particle includes a silica particle body and a titania coating layer formed on a surface of the silica particle body through a reaction of a titanium compound having a structure in which a hydrocarbon group bonds to a titanium atom through an oxygen atom. The silica particle has absorption at a wavelength of about 400 nm or more and about 800 nm or less in an ultraviolet-visible absorption spectrum.

Abstract: The present invention relates to a photocatalytic nanocomposite material, wherein the realization of the optimal wavelength for optical activation is controlled and accordingly is designed to work together with a LED operating at the wavelength for yielding the maximum efficiency.

Abstract: A method (P) for hydrosilylating at least one compound (C), including at least one unsaturation in the presence of an organosilicon compound (O) including at least one hydrogen atom per molecule bonded directly to a silicon atom, and of a catalytic hydrosilylation system including a structured porous material (A) including pores and an inorganic structure consisting of silicon oxide walls, in which metal nanoparticles are contained.

Abstract: The present invention relates to a process for producing a structured porous material comprising a structured inorganic framework made up of metal-oxide based walls in which nanoparticles of metal 0 are incorporated, which comprises the following steps: a) formation of a suspension of hydrophilic nanoparticles of metal 0 stabilized by non-exchangeable ligands that give the nanoparticles their hydrophilic character; b) growth of the inorganic framework from an inorganic precursor around the nanoparticles of metal 0 stabilized by the non-exchangeable hydrophilic ligands, in the presence of a pore-forming agent; and c) elimination of the pore-forming agent and at least partially of the non-exchangeable ligands that give the nanoparticles their hydrophilic character.

Abstract: A device, system, and method, for the formation of advanced oxidation products by contacting a hydrated catalytic surface of a catalytic target structure with broad spectrum ultraviolet light in the 100 nm to 300 nm range that preferably includes 185 nm and 254 nm wavelengths. The catalytic surface reacts with the ultraviolet light energy and hydrate at the catalytic surface to form advanced oxidation products, The catalytic surface in one embodiment includes a hydrophilic agent, titanium dioxide, silver, copper, and rhodium. Preferably, the catalytic surface is coated with a coating that includes the hydrophilic; agent, titanium dioxide, silver, copper, and rhodium. A photohydroionization cell (100) that includes an ultraviolet light source (204) and a catalytic target structure (110) in an air environment to form advanced oxidation product is also provided. A U.V. light indicator and a monitor and/or control system for the photohydroionization cell (100) are also provided.

Abstract: This invention relates to a protected organotin-based catalyst system for polyurethane synthesis that is useful in coatings applications. The catalyst has a formula according to; R1aR2bR3cSn[CH(OX)R4]d, wherein R1, R2, and R3 are the same or different and represent an optionally substituted hydrocarbyl, aromatic, alkoxide, amide, halide or stannyl group, R4 represents an optionally substituted hydrocarbyl or optionally substituted aryl group. a, b, and c are independently 0, 1, 2, or 3; d is 1, 2 or 3; and a+b+c+d=4; and X is an acid-labile or moisture-labile protecting group. When a coating mixture comprising the catalyst is sprayed and/or applied to a substrate as a thin film in air, the catalyst is activated. For solvent-based refinish systems comprising hydroxyl and isocyanate species at high solids levels, the catalyst system therefore provides extended viscosity stability, i.e., pot life.

Abstract: This invention relates to an organotin-based catalyst system for polyurethane synthesis that is useful in coatings applications. The catalyst has low activity in the absence of oxygen. When a coating mixture comprising the catalyst is sprayed and/or applied to a substrate as a thin film in air, the catalyst is activated. For solvent-based refinish systems comprising hydroxyl and isocyanate species at high solids levels, the catalyst system therefore provides extended viscosity stability, i.e., pot life.

Abstract: Disclosed is a photocatalyst comprising a photocatalytically active base, and a silicon oxide film covering the base and substantially having no pores. The alkali metal content of the photocatalyst is not less than 1 ppm but not more than 1,000 ppm. Also disclosed is a method for producing such a photocatalyst wherein when a photocatalytically active base present in an aqueous medium is coated with a silicon oxide film by using a silicate, the pH of the aqueous medium containing both the photocatalytically active base and the silicate is maintained at 5 or below.

Abstract: A process for the preparation of a TiO2-containing catalyst or catalyst support which is stable to high temperatures is described. In this process an aqueous Ti-containing solution having a concentration of dissolved Ti equivalent to 10 to 250 g TiO2 per liter of solution is added to a suspension of not more than 10 wt. % strength of a finely disperse inorganic support material in water, the inorganic support material having a specific surface area, measured by the BET method, of >20 m2/g and any primary particle agglomerates present having a particle size of d50<10 ?m, preferably <5 ?m, the rate of addition of the Ti-containing solution to the suspension being chosen such that an addition equivalent to 0.05 g TiO2 per m2 of support surface and hour is not exceeded, the TiO2 is precipitated on the inorganic support and the product obtained is filtered, washed and calcined.

Abstract: A method for making an inorganic oxide supported catalyst involves impregnating an inorganic oxide component with a catalytic metal using an aqueous, acid bath. More specifically, the method involves forming and washing an inorganic oxide component, such as a silica gel or a silica co-gel, for example a silica-zirconia co-gel. The washed inorganic oxide component is then contacted with the acidic bath to effect the impregnation with the catalytic metal, such as cesium, to form an activated inorganic oxide component. Subsequently, the activated component is dried to form the catalyst. The resulting catalysts possess increased surface area, which is beneficial with respect to accessibility and amount of catalytically active sites.

Abstract: In one embodiment, a reforming catalyst can include indium, tin, and a catalytically effective amount of a group VIII element for one or more reforming reactions. Typically, at least about 25%, by mole, of the indium is an In(3+) species based on the total moles of indium after exposure for about 30 minutes in an atmosphere including about 100% hydrogen, by mole, at a temperature of about 565° C. Usually, no more than about 25%, by mole, of the tin is a Sn(4+) species based on the total moles of tin after exposure for about 30 minutes in an atmosphere including about 100% hydrogen, by mole, at a temperature of about 565° C.

Abstract: A catalyst composition comprising titanium incorporated into a silica support, characterized in that the silica support is a shaped extrudate of silica powder. The catalyst composition is useful in the epoxidation of olefins into alkylene oxides using organic hydroperoxides. The composition can be prepared by extruding silica powder into an extrudate having a selected shape; calcining the extrudate; impregnating the extrudate with a titanium-containing impregnating agent; and drying and calcining the impregnated extrudate.

Abstract: The invention relates to a process for preparing an essentially spherical support for olefin polymerization catalysts, which comprises the steps: preparation of a hydrogel comprising a cogel of silicon oxide and at least one further metal oxide, if appropriate, washing of the hydrogel until the content of alkali metal ions is less than 0.1% by weight, based on the weight of solids, extraction of the water from the hydrogel until the water content is less than 5% by weight, based on the total content of liquid, and drying of the hydrogel to form a xerogel. According to the invention, the extraction step comprises at least one first extraction with a first organic solvent which is at least partially miscible with water down to a water content of 50% by weight, followed by at least one second extraction with a second organic solvent which is at least partially miscible with water.

Abstract: A bulk metal oxide catalyst composition of the general formula (X)b(M)c(Z)d(O)e??(I) wherein X represents at least one non-noble Group VIII metal; M represents at least one non-noble Group VIb metal; Z represents one or more elements selected from aluminium, silicon, magnesium, titanium, zirconium, boron, and zinc; one of b and c is the integer 1; and d and e and the other of b and c each are a number greater than 0 such that the molar ratio of b:c is in the range of from 0.5:1 to 5:1, the molar ratio of d:c is in the range of from 0.2:1 to 50:1, and the molar ratio of e:c is in the range of from 3.7:1 to 108:1; is prepared by controlled (co)precipitation of component metal compounds, refractory oxide material, and alkali compound in protic liquid. Resulting compositions find use in hydrotreatment processes involving particularly hydrodesulphurisation and hydrodenitrification.

Abstract: A photocatalytic coating composition comprising a photocatalyst, a silicon alkoxide, a zirconium compound, colloidal silica, and a liquid medium, wherein a content of the zirconium compound in terms of zirconium atoms is 0.3 to 3 times by mole a content of the silicon alkoxide in terms of silicon atoms, which can form a coating film of a photocatalyst with a high adhesion strength to a substrate.

Abstract: The invention relates to highly active spherical metal support catalysts with a metal content of 10 to 70% by mass, and a process for their production with the use of a mixture of polysaccharides and at least one metal compound which is dropped into a metal salt solution.

Abstract: The invention relates to a process for preparing an essentially spherical support for olefin polymerization catalysts, which comprises the steps: preparation of a hydrogel comprising a cogel of silicon oxide and at least one further metal oxide, if appropriate, washing of the hydrogel until the content of alkali metal ions is less than 0.1% by weight, based on the weight of solids, extraction of the water from the hydrogel until the water content is less than 5% by weight, based on the total content of liquid, and drying of the hydrogel to form a xerogel. According to the invention, the extraction step comprises at least one first extraction with a first organic solvent which is at least partially miscible with water down to a water content of 50% by weight, followed by at least one second extraction with a second organic solvent which is at least partially miscible with water.

Abstract: A carrier supporting titania thereon is further caused to carry a metal compound thereon. This metal compound is hydrogen reduced in a heating atmosphere at a first treatment temperature, then oxidized in a heating atmosphere at a second treatment temperature not higher than the first treatment temperature to thereby obtain a photocatalyst. In this event, metal is released from an extremely strong reduction state and thus highly dispersed on the catalyst in the form of fine particles so that high activity of the catalyst can be obtained. Then, by purifying gas while feeding light and heat to the photocatalyst by, for example, blacklights, a volatile organic compound such as acetaldehyde can be decomposed at a high decomposition rate through cooperation between photocatalytic activity and thermal catalytic activity of the photocatalyst.

Abstract: The invention relates to a process for the preparation of an epoxidation catalyst which process involves (a) drying a silica gel carrier having a weight average particle size of from 0.1 mm to 2 mm at a temperature of from more than 200° C. to 300° C., and (b) contacting the carrier obtained in step (a) with a gas stream containing titanium halide to obtain an impregnated carrier, and the use of such catalyst in the preparation of alkylene oxide.

Abstract: The invention concerns a filtering medium based on a photocatalytic agent and activated carbon, characterized in that it comprises a permeable support covered with a first layer based on activated carbon, then a separate second layer based on a photocatalytic agent, or vice versa. The invention also concerns a method for making such a filtering medium.

Abstract: A coated metal substrate useful for carrying an exhaust emission treatment catalyst such as a three-way conversion catalyst for use with small engine platforms. The coated metal substrate comprises a metal such as a stainless steel, a carbon steel, a FeCr alloy, HASTELLOY® and the like. The coating on the metal substrate comprises an alumina silicate having alumina particles impregnated therein. The coating is applied using a liquid dispersion containing an aluminum silicate and the alumina particles are dispersed into the aluminum silicate coating while the coating is still wet. The coated metal substrate is then calcined. Thereafter, a washcoat containing an engine exhaust treatment catalyst may be applied to the surface of the coated metal substrate.

Abstract: A method and device for loading a catalyst into a chamber. The catalyst loading is well suited for production of hydrogen producing microreactors. The catalyst is coated onto a strip which is mountable within the chamber.

Abstract: A catalyst support is produced by mixing particulate synthetic silica with 0.5–10 parts by weight of one or more particulate oxides or phosphates of the elements of group IIA, IIIB, IVB, VA, VIB, VIIB, VIII, IB, IIB, IIIA, IVA and lanthanides or precursors thereof, shaping the mixture and then calcining the shaped mixture to form the finished support. The formed support has improved stability relative to aging resistance under hydrothermal conditions. The catalyst support is used together with phosphoric acid in the production of alcohols from olefins by hydration. The resultant hydration catalysts have excellent activity and selectivity.

Abstract: The present invention relates to noble metal-containing catalysts which are composed of at least one organic/inorganic hybrid material which is composed of at least one titanium component and at least one Si—H group. The catalysts of the present invention have increased activity compared to known catalysts.

Abstract: A catalyst support is produce by mixing particulate synthetic silica with 0.5–10 parts by weight of one or more particulate oxides or phosphates of the elements of group IIA, IIIB, IVB, VA, VIB, VIIB, VIII, IB, IIB, IIIA, IVA and lanthanides or precursors thereof, shaping the mixture and then calcining the shaped mixture to form the finished support. The formed support has improved stability relative to aging resistance under hydrothermal conditions. The catalyst support is used together with phosphoric acid in the production of alcohols from olefins by hydration. The resultant hydration catalysts have excellent activity and selectivity.

Abstract: The present invention is directed to a novel one-step method for forming a supported catalyst complex of high activity by substantially simultaneously contacting a bidentate or tridentate ligand forming compound, a transition metal compound and a chromium immobilized Lewis acid support-agglomerate. The catalyst can be formed prior to polymerization of olefins or within the polymerization reaction zone.

Abstract: The invention relates to a composite material comprising silicon and titanium dioxide characterized by an enhanced thermal and hydrothermal stability of the pore structure. The composite is obtainable by precipitating titanium hydroxide from an aqueous solution containing sulfate salts and urea, followed by an hydrothermal treatment in the mother liquor, and by reacting the precipitate with a basic silica sol. The composite has a specific surface area of up to 228 m2/g for a material calcined at 800° C. for 3 hours, and is suitable for catalyzing a variety of reactions, including Claus reaction and degradation of organic impurities.

Abstract: A method for making a silica supported catalyst involves impregnating a silica component with a catalytic metal using an aqueous, alkaline bath before drying. More specifically, the method involves forming and washing a silica component, such as a silica gel or a co-gel, for example a silica-zirconia co-gel. Then, the washed silica component is contacted with the alkaline bath to effect the impregnation with the catalytic metal, such as cesium, to form an activated silica component. Subsequently, the activated silica component is dried to form the catalyst. The resulting catalysts demonstrate good mechanical strength.

Abstract: A method is for producing monolithic substrate catalysts and for their use in the gas phase oxidation of hydrocarbons. The catalysts are obtained by coating the catalyst substrate with a suspension that includes a catalytically active compound and one or more surfactants of the general formula RnYmX. R represents the hydrophobic part of the surfactant, with n being 1, 2 or 3. Y represents the hydrophobic part of the surfactant, with m being 0, 1, 2, or 3 and X represents the hydrophilic head group of the surfactant.

Abstract: The silica gel carrying a titanium oxide photocatalyst in a high concentration of the present invention is characterized in that the concentration of the titanium oxide contained in the pores near the surface of the silica gel is 7-70% by weight, said silica gel having an average pore diameter of 6-100 nm, provided that the concentration gradient is provided such that the amount of the titanium oxide contained in the pores near the surface of the silica gel is 1.5 times or more than the amount of the titanium oxide contained in the pores near the central part of the silica gel.

Abstract: This invention relates to a method for purifying and drying a polymer hydrogel. This invention is based in part upon the discovery that rapid drying of polymer hydrogels can eliminate the problem of unacceptable levels of soluble oligomers caused by prolonged thermal treatment. Rapid drying techniques allow drying hydrogels containing more water than was previously considered possible without a loss in product quality. Furthermore, it was discovered that slurries comprising polymer hydrogels and large quantities of water can be spray dried and that spray drying can be conducted with only minimal oligomer formation.

Abstract: Scaly silica particles having a laminated structure, consisting essentially of secondary particles of foliar silica, each formed by a plurality of flaky primary particles of scaly silica which are overlaid one on another and aligned face-to-face in parallel with one another, said secondary particles being present independent of one another.

Abstract: This invention relates to metallocene catalyst compositions which are highly active for the polymerization of olefins, particularly prochiral &agr;-olefins. The catalyst compositions contain at least one metallocene, and least one activator and a support that has been fluorided using a fluoride containing compound.

Abstract: The present invention includes a sol-gel supported catalyst for the dehydrogenation of lower alkanes, the catalyst comprising at least one active metal and at least one promoter metal attached to a sol-gel mixed oxide support. The sol-gel mixed oxide support arises from the polymerization of at least one precursor. The active metal and the promoter metal have been attached to the sol-gel mixed oxide support by the active metal and the promoter metal having been co-precipitated with the precursor of the sol-gel mixed oxide support. The invention also includes a method of making the above mentioned catalyst and a method of using the catalyst to dehydrogenate lower alkanes to produce lower alkenes.

Abstract: Moldings are disclosed for use as a catalyst or catalyst support for hydrating olefin, such as ethylene and propylene. The moldings are based on a pyrogenically produced mixed oxide having the following physicochemical parameters: External diameter 0.8-25 mm BET surface area 5-400 m2/g Pore volume 0.2-1.8 ml/g Fracture strength 5 to 350 N Composition At least two materials selected from the group of SiO2, Al2O3, TiO2 and ZrO2 in any desired combination, with the proviso that when the combination is a SiO2/Al2O3 mixed oxide, at least 75 wt. % of SiO2 is present based on the total weight of the mixed oxide. Other constituents <1 wt. % Bulk density 250-1500 g/l.

Abstract: The present invention relates to a chromium/silica-aluminophosphate catalyst, titanated under specific conditions and used for the homopolymerisation or the copolymerisation of ethylene. The polyethylene obtained with this catalyst has a high melt potential and a high shear resistance. The catalyst has a high level of activity.

Abstract: The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses.

Abstract: A method for preparing a titanium on silica catalyst, in the form of formed particles such as macrospheres, achieves a controlled titanium distribution type, namely either uniform, eggshell, or intermediate, by selecting the particular titanium precursor depending on its reactivity with hydroxyl groups and by selecting the molar titanium:hydroxyl ratio. Selecting a titanium precursor with a low reactivity and/or adding sufficient titanium precursor to achieve a high molar titanium:hydroxyl ratio aids in forming a uniform distribution of titanium. On the other hand, selecting a titanium precursor with a high reactivity and/or adding only a little titanium precursor resulting in a low molar titanium:hydroxyl ratio aids in forming an eggshell distribution of titanium.

Abstract: This invention relates to a process for producing an enhanced adsorbent particle comprising contacting a non-amorphous, non-ceramic, crystalline, porous, calcined, aluminum oxide particle that was produced by calcining at a particle temperature of from 300° C. to 700° C., with an acid for a sufficient time to increase the adsorbent properties of the particle. A process for producing an enhanced adsorbent particle comprising contacting a non-ceramic, porous, oxide adsorbent particle with an acid for a sufficient time to increase the adsorbent properties of the particle is also disclosed. Particles made by the process of the instant invention and particle uses, such as remediation of waste streams, are also provided. The invention also relates to a method for producing an adsorbent and/or catalyst and binder system. The invention also relates to particles made by the process, binders, and methods for remediating contaminants in a stream.

Abstract: Frangible, spray dried agglomerate catalyst supports are provided, e.g. of silica gel, which possess a controlled morphology of microspheroidal shape, rough, scabrous appearance, and interstitial void spaces which penetrate the agglomerate surface and are of substantially uniform size and distribution. The agglomerates also possess a 1-250 micron particle size, 1-1000 m2/gm. surface area, and an Attrition Quality Index (AQI) of at least 10. The agglomerates are derived from a mixture of dry milled inorganic oxide particles, e.g. silica gel, and optionally but preferably wet milled inorganic oxide particles, e.g. silica gel particles, (which preferably contain a colloidal segment of <1 micron particles) slurried in water for spray drying. The high AQI assures that the agglomerates are frangible and that polymerization performance is improved.

Abstract: A titanium-containing silicon oxide catalyst satisfying all of the following conditions (1) to (4): (1): an average pore size of 10 Å or more, (2): a pore size of 90% or more of the total pore volume of 5 to 200 Å, (3): a specific pore volume of 0.2 cm3/g or more, and (4): a quarternary ammonium ion represented by the following general formula (I) is used as a template and then said template is removed by solvent extraction operation; [NR1R2R3R4]+  (I) wherein, R1 represents a linear or branched hydrocarbon chain having 2 to 36 carbon atoms, and R2 to R4 represent an alkyl group having 1 to 6 carbon atoms, a method for producing said catalyst, and a method for producing propylene oxide by reacting propylene with a hydroperoxide, except for ethylbenzene hydroperoxide, in the presence of said catalyst.

Abstract: Provided area catalyst for polymerizing olefinic monomers, which comprises (a) a transition metal compound, (b) at least one member selected from clay, clay minerals and ion-exchanging layered compounds, (c) a silane compound, and optionally (d) an alkylating agent; a catalyst for polymerizing olefinic monomers, which comprises (a) a transition metal compound, (b) at least one member selected from clay, clay minerals and ion-exchanging layered compounds, (c) a silane compound, and optionally (e) an organic aluminum compound, and further optionally (d) an alkylating agent; and a method for producing olefinic polymers or styrenic polymers, which comprises homopolymerizing or copolymerizing olefinic or styrenic monomers in the presence of the catalyst for polymerizing olefinic monomers. The method does not require a large amount of aluminoxane, and the catalyst to be used therein has high polymerization activity.

Abstract: A method of making frangible, spray dried agglomerate catalyst supports is provided, e.g. of silica gel, which possess a controlled morphology of microspheroidal shape, preferably a rough, scabrous appearance, and interstitial void spaces which penetrate the agglomerate. The agglomerates also possess a 4-250 micron particle size, 1-1000 m2/gm. surface area, and an Attrition Quality Index (AQI) of at least 10. The method comprises dry milling inorganic oxide particles, e.g. silica gel, wet milling the dry milled inorganic oxide particles (to preferably impart a colloidal segment of <1 micron particles), and spray drying the particles. The high AQI assures that the agglomerates are frangible and that polymerization performance is improved. The controlled morphology is believed to permit the constituent particles of the agglomerates to be more uniformly impregnated or coated with conventional olefin polymerization catalysts.

Abstract: A method for preparing a titanium on silica catalyst, in the form of formed particles such as macrospheres, achieves a controlled titanium distribution type, namely either uniform, eggshell, or intermediate, by selecting the particular titanium precursor depending on its reactivity with hydroxyl groups and by selecting the molar titanium:hydroxyl ratio. Selecting a titanium precursor with a low reactivity and/or adding sufficient titanium precursor to achieve a high molar titanium:hydroxyl ratio aids in forming a uniform distribution of titanium. On the other hand, selecting a titanium precursor with a high reactivity and/or adding only a little titanium precursor resulting in a low molar titanium:hydroxyl ratio aids in forming an eggshell distribution of titanium. In particular, the method involves first preparing formed particles, such as macrospheres, of silica hydrogel then drying the formed particles.

Abstract: The photocatalyst granules of the present invention are photocatalyst granules prepared by molding a mixture containing photocatalyst particles and colloidal silica, and drying the molded mixture, wherein the content of the photocatalyst particles in the photocatalyst granules is 10% by weight or more.