Abstract: Process for producing fumed silica powder with a decreased silanol group density, comprising subjecting a fumed surface untreated silica powder with a silanol density dSiOH of at least 1.2 SiOH/nm2 and a particle size d90 of not more than 10 ?m, to thermal treatment at a temperature of 350° C. to 1250° C. for 5 min to 5 h, wherein the temperature and the duration of the thermal treatment are chosen so that dSiOH of the silica is decreased by 10%-70% relative to dSiOH of the employed thermally untreated silica, wherein the thermal treatment is carried out while the fumed silica powder is in motion, followed by optional surface treatment. Surface unmodified and modified fumed silica powders obtained by this process and the use thereof.

Abstract: The invention provides fumed silica granules having a BET surface area of 20 m2/g to 500 m2/g; a number average particle size d50 of 350 ?m to 2000 ?m; a span (d90?d10)/d50 of particle size distribution of 0.8-3.0; a bulk density of more than 0.35 g/mL; a pore volume for pores >4 nm of not more than 1.5 cm3/g, process for its preparation and use thereof as a catalyst carrier, a carrier for liquid substances, in cosmetic applications, for thermal insulation, as pharmaceutical excipient, in producing thermally treated silica granules, as an abrasive, as a component of a silicone rubber.

Abstract: Fumed silica powder, surface treated with a surface treatment agent selected from the group consisting of organosilanes, silazanes, acyclic polysiloxanes, cyclic polysiloxanes, and mixtures thereof, wherein the powder has: a) a number of silanol groups relative to BET surface area dSiOH of at least 0.85 SiOH/nm2, as determined by reaction with lithium aluminium hydride; b) a methanol wettability of more than 40% by volume of methanol in methanol-water mixture; c) a tamped density of not more than 200 g/L.

Abstract: Surface-treated fumed silica, with a tribo-electro static charge of ?500 ?C/g to +500 ?C/g, a ratio of the tribo-electro static charge to BET surface area of ?3.5 ?C/m2 to +3.5 ?C/m2, a methanol wettability of at least 20% by volume methanol in methanol/water mixture, a ratio of carbon content to BET surface area of at most 0.020 wt. %*g/m2, a process for its preparation and the use thereof.

Abstract: A process for production of silica having variable thickening wherein a) a product stream I containing at least a vaporous, hydrolysable and/or oxidizable silicon compound, b) a product stream II containing oxygen and c) a product stream III containing at least a combustible gas are made to react, where d) a feed port in a pipepiece A, the pipepiece A containing one or more static mixing elements, is used to import product stream I into product stream II, or vice versa and thereby create product stream IV, then e) a feed port in a pipepiece B, the pipepiece B containing one or more static mixing elements, is used to import product stream III in product stream IV and thereby create product stream V, f) product stream V leaving pipepiece B is imported into a reaction chamber, ignited therein and reacted in a flame, and g) the resultant solid material is separated off.

Abstract: A process for production of silica having variable thickening wherein a) a product stream I containing at least a vaporous, hydrolysable and/or oxidizable silicon compound, b) a product stream II containing oxygen and c) a product stream III containing at least a combustible gas are made to react, where d) a feed port in a pipepiece A, the pipepiece A containing one or more static mixing elements, is used to import product stream I into product stream II, or vice versa and thereby create product stream IV, then e) a feed port in a pipepiece B, the pipepiece B containing one or more static mixing elements, is used to import product stream III in product stream IV and thereby create product stream V, f) product stream V leaving pipepiece B is imported into a reaction chamber, ignited therein and reacted in a flame, and g) the resultant solid material is separated off.

Abstract: Process for production of silica having variable thickening wherein a) a product stream I comprising at least a vaporous, hydrolysable and/or oxidizable silicon compound, b) a product stream II comprising oxygen and c) a product stream III comprising at least a combustible gas are made to react, characterized in that d) a feed port in a pipepiece A, said pipepiece A comprising one or more static mixing elements, is used to import product stream I into product stream II, or vice versa and thereby create product stream IV, then e) a feed port in a pipepiece B, said pipepiece B comprising one or more static mixing elements, is used to import product stream III in product stream IV and thereby create product stream V, f) product stream V leaving pipepiece B is imported into a reaction chamber, ignited therein and reacted in a flame, and g) the resultant solid material is separated off.

Abstract: Process for production of silica having variable thickening wherein a) a product stream I comprising at least a vaporous, hydrolysable and/or oxidizable silicon compound, b) a product stream II comprising oxygen and c) a product stream III comprising at least a combustible gas are made to react, characterized in that d) a feed port in a pipepiece A, said pipepiece A comprising one or more static mixing elements, is used to import product stream I into product stream II, or vice versa and thereby create product stream IV, then e) a feed port in a pipepiece B, said pipepiece B comprising one or more static mixing elements, is used to import product stream III in product stream IV and thereby create product stream V, f) product stream V leaving pipepiece B is imported into a reaction chamber, ignited therein and reacted in a flame, and g) the resultant solid material is separated off.

Abstract: Process for the production of doped metal oxide particles, wherein the doping component is present on the surface in the form of domains, wherein in a first reaction zone, an oxidizable and/or —hydrolysable metal compound as dopant together with an atomization gas is atomized into a flow of metal oxide particles in a carrier gas, wherein the mass flow of the metal oxide particles und —the mass flow of the dopant are selected such that the doped metal oxide particles contain 10 ppm to 10 wt.

Abstract: Provided is a crystalline TiO2 powder in the form of aggregated primary particles having a variable sintering stability at a BET surface area of 70-100 m2/g and a rutile content of greater than 10% but less than or equal to 40%, and a process for preparing the crystalline TiO2 powder, which involves: introducing a TiCl4 vapor and, separately therefrom, H2 and a primary air into a mixing chamber to produce a gaseous mixture; igniting the gaseous mixture in a burner to produce a flame, which is burned into a reaction chamber to produce the crystalline TiO2 powder and gaseous substances; and separating the crystalline TiO2 powder from the gaseous substances, wherein the relative amounts of TiCl4 vapor, H2 and primary air are selected to provide crystalline TiO2 powder having the aforementioned BET surface area and rutile content, with the proviso that factor A has a value of 0.1-0.4 g/m2 in accordance within the following formula: factor A=105{[(TiCl4 vapor×H2)/(amount of air×gaseous mixture)]/BET]}.

Abstract: A crystalline titanium dioxide powder, containing aggregated primary particles, wherein a BET surface area of the aggregated primary particles is from 30 to 65 m2/g, and a rutile content of a sum of crystalline modifications in the crystalline titanium dioxide is from of 50-70%.

Abstract: Alkali metal oxide-metal oxide mixed oxide powder in the form of aggregates of pore-free primary particles, comprising from 0.005 to 5% by weight of at least one alkali metal oxide, which has a BET surface area of from 100 to 350 m2/g, has a specific DBP number, expressed as DBP number per square meter of specific surface area, greater than or equal to that of a powder which has only the metal oxide component, has the alkali metal oxide distributed in the core and on the surface of the primary particles. Silicone rubber comprising the alkali metal oxide-metal oxide mixed oxide powder.

Abstract: A method for producing potassium-doped pyrogenic oxides involves mixing a gaseous mixture including a pyrogenic oxide precursor and an aqueous aerosol containing a potassium salt to form an aerosol-gaseous mixture which is then reacted in a flame under conditions suitable for producing pyrogenic oxides by flame oxidation or flame hydrolysis to form the potassium-doped pyrogenic oxides product. The particle product is spherical, has a BET surface between 1 and 1000 m2/g and a narrow distribution of particle size of at least 0.7. The doped oxides can be used as polishing material (CMP application).

Abstract: Provided is a crystalline TiO2 powder in the form of aggregated primary particles having a variable sintering stability at a BET surface area of 70-100 m2/g and a rutile content of greater than 10% but less than or equal to 40%, and a process for preparing the crystalline TiO2 powder, which involves: introducing a TiCl4 vapor and, separately therefrom, H2 and a primary air into a mixing chamber to produce a gaseous mixture; igniting the gaseous mixture in a burner to produce a flame, which is burned into a reaction chamber to produce the crystalline TiO2 powder and gaseous substances; and separating the crystalline TiO2 powder from the gaseous substances, wherein the relative amounts of TiCl4 vapor, H2 and primary air are selected to provide crystalline TiO2 powder having the aforementioned BET surface area and rutile content, with the proviso that factor A has a value of 0.1-0.4·105 g/m2 in accordance within the following formula: factor A=105{[(TiCl4 vapor×H2)/(primary air×gaseous mixture)]/BET]}.

Abstract: Aluminium oxide powder produced by flame hydrolysis and consisting of aggregates of primary particles, having a BET surface area of from 100 to 250 m2/g, a dibutyl phthalate absorption of from 50 to 450 g/100 g of aluminium oxide powder, which powder shows only crystalline primary particles in high-resolution TEM pictures.

Abstract: A crystalline titanium dioxide powder, containing aggregated primary particles, wherein a BET surface area of the aggregated primary particles is from 30 to 65 m2/g, and a rutile content of a sum of crystalline modifications in the crystalline titanium dioxide is from of 50-70%.

Abstract: Carbon black with an OAN, measured on the beaded carbon black, of less than 120 ml/100 g. A process for the preparation of the carbon black is described, wherein a salt solution is converted into an aerosol and this is then introduced into the carbon black formation zone. The carbon black can be used in inks, paints, lacquers, printing inks and ink-jet inks, and for coloring plastics.

Abstract: Provided is a crystalline TiO2 powder in the form of aggregated primary particles having a variable sintering stability at a BET surface area of 70-100 m2/g and a rutile content of greater than 10% but less than or equal to 40%, and a process for preparing the crystalline TiO2 powder, which involves: introducing a TiCl4 vapor and, separately therefrom, H2 and a primary air into a mixing chamber to produce a gaseous mixture; igniting the gaseous mixture in a burner to produce a flame, which is burned into a reaction chamber to produce the crystalline TiO2 powder and gaseous substances; and separating the crystalline TiO2 powder from the gaseous substances, wherein the relative amounts of TiCl4 vapor, H2 and primary air are selected to provide crystalline TiO2 powder having the aforementioned BET surface area and rutile content, with the proviso that factor A has a value of 0.1-0.4·105 g/m2 in accordance within the following formula: factor A=105{[(TiCl4 vapor×H2)/(primary air×gaseous mixture)]/BET]}.

Abstract: Process for the production of doped metal oxide particles, wherein the doping component is present on the surface in the form of domains, wherein in a first reaction zone, an oxidizable and/or - hydrolysable metal compound as dopant together with an atomization gas is atomised into a flow of metal oxide particles in a carrier gas, wherein the mass flow of the metal oxide particles und - the mass flow of the dopant are selected such that the doped metal oxide particles contain 10 ppm to 10 wt.

Abstract: A crystalline titanium dioxide powder, containing aggregated primary particles, wherein a BET surface area of the aggregated primary particles is from 30 to 65 m2/g, and a rutile content of a sum of crystalline modifications in the crystalline titanium dioxide is from of 50-70%.