摘要:
Process for the production of a metal oxide powder having a BET surface area of at least 20 m2/g by reacting an aerosol with oxygen in a reaction space at a reaction temperature of more than 700° C. and then separating the resulting powder from gaseous substances in the reaction space, wherein the aerosol is obtained by atomisation using a multi-component nozzle of at least one starting material, as such in liquid form or in solution, and at least one atomising gas, the volume-related mean drop diameter D30 of the aerosol is from 30 to 100 μm and the number of aerosol drops larger than 100 μm is up to 10%, based on the total number of drops, and metal oxide powder obtainable by this process.
摘要:
Process for the production of a metal oxide powder having a BET surface area of at least 20 m2/g by reacting an aerosol with oxygen in a reaction space at a reaction temperature of more than 700° C. and then separating the resulting powder from gaseous substances in the reaction space, wherein the aerosol is obtained by atomisation using a multi-component nozzle of at least one starting material, as such in liquid form or in solution, and at least one atomising gas, the volume-related mean drop diameter D30 of the aerosol is from 30 to 100 μm and the number of aerosol drops larger than 100 μm is up to 10%, based on the total number of drops, and metal oxide powder obtainable by this process.
摘要:
Polycrystalline cerium oxide powder in the form of aggregates of primary particles with a specific surface of between 70 and 150 m2/g, an average primary particle diameter of between 5 and 20 nm and an average, projected aggregate diameter of between 20 and 100 nm. It is produced in that an aerosol is reacted in a flame obtained from a hydrogen-containing combustible gas and primary air and the solid obtained is then separated from the gaseous substances.
摘要:
Polycrystalline cerium oxide powder in the form of aggregates of primary particles with a specific surface of between 70 and 150 m2/g, an average primary particle diameter of between 5 and 20 nm and an average, projected aggregate diameter of between 20 and 100 nm. It is produced in that an aerosol is reacted in a flame obtained from a hydrogen-containing combustible gas and primary air and the solid obtained is then separated from the gaseous substances.
摘要:
Process for the production of a metal oxide powder having a BET surface area of at least 20 m2/g by reacting an aerosol with oxygen in a reaction space at a reaction temperature of more than 700° C. and then separating the resulting powder from gaseous substances in the reaction space, wherein the aerosol is obtained by atomisation using a multi-component nozzle of at least one starting material, as such in liquid form or in solution, and at least one atomising gas, the volume-related mean drop diameter D30 of the aerosol is from 30 to 100 μm and the number of aerosol drops larger than 100 μm is up to 10%, based on the total number of drops, and metal oxide powder obtainable by this process.
摘要:
Cerium oxide powder having carbonate groups and made of crystalline primary particles containing cerium oxide and having carbonate groups on the surface and in a region close to the surface, and having a BET surface area of from 25 to 150 m2/g, a mean diameter of from 5 to 50 nm, a carbonate concentration in the region close to the surface decreasing inwardly from the surface, a carbon content due to carbonate groups on the surface of from 5 to 50% by area, a carbon content due to carbonate groups at a depth of about 5 nm in a region close to the surface of from 0 to 30% by area, a content of cerium oxide calculated as CeO2 and based on the powder of at least 99.5% by weight and a content of organic and inorganic carbon of from 0.01 to 0.3% by weight. A dispersion containing this powder.
摘要:
Cerium oxide powder having carbonate groups and made of crystalline primary particles containing cerium oxide and having carbonate groups on the surface and in a region close to the surface, and having a BET surface area of from 25 to 150 m2/g, a mean diameter of from 5 to 50 nm, a carbonate concentration in the region close to the surface decreasing inwardly from the surface, a carbon content due to carbonate groups on the surface of from 5 to 50% by area, a carbon content due to carbonate groups at a depth of about 5 nm in a region close to the surface of from 0 to 30% by area, a content of cerium oxide calculated as CeO2 and based on the powder of at least 99.5% by weight and a content of organic and inorganic carbon of from 0.01 to 0.3% by weight. A dispersion containing this powder.
摘要:
Nanoscale, pyrogenically produced zinc oxide having a BET surface area of 10 to 200 m2/g, which is in the form of aggregates of anisotropic primary particles and whereby the aggregates display an average diameter of 50 to 300 nm. It is obtained from zinc powder, which is converted to zinc oxide powder in the four successive reaction zones, evaporation zone, nucleation zone, oxidation zone and quench zone. It can be used in sunscreen formulations.
摘要:
Nanoscale, pyrogenically produced zinc oxide having a BET surface area of 10 to 200 m2/g, which is in the form of aggregates of anisotropic primary particles and whereby the aggregates display an average diameter of 50 to 300 nm. It is obtained from zinc powder, which is converted to zinc oxide powder in the four successive reaction zones, evaporation zone, nucleation zone, oxidation zone and quench zone. It can be used in sunscreen formulations.
摘要:
Zinc silicon oxide particles with a core-shell structure which have a Zn/Si ratio of from 2 to 75, in atom %/atom %, whose fraction of Zn, Si and O is at least 99% by weight, based on the zinc silicon oxide particles, which have a BET surface area of from 10 to 60 m2/g, a weight-averaged primary particle diameter of from 10 to 75 nm an average aggregate area of less than 40 000 nm2 and an average aggregate diameter (ECD) of less than 200 nm, whose core is crystalline and consists of aggregated primary particles of zinc oxide and whose shell surrounds the aggregated zinc oxide primary particles and consists of one or more compounds containing the elements Si and O. Dispersion, coating composition and sunscreen formulation comprise the zinc silicon oxide particles.