Patent ID: 8535633
Filing Date: 2013-09-17
Classification: C01B,C01G,C01P,C09C,C23C

Abstract:
1. A process, comprising: atomizing, in a first reaction zone, a dopant that comprises and an atomization gas into a flow of metal oxide particles of an oxide of at least one of aluminium, boron, cerium, germanium, niobium, silicon, tantalum, vanadium, tungsten, zinc, and zirconium in a carrier gas to obtain metal oxide particles having a dopant present on surfaces thereof, wherein the mass flow of the metal oxide particles and the mass flow of the dopant are selected such that the doped metal oxide particles comprise 10 ppm to 10 wt % of the dopant, where the quantity of dopant to be introduced is calculated as the corresponding oxide, and wherein the temperature in the first reaction zone is selected such that it is below the boiling temperature of the dopant under the prevailing reaction conditions and is below a reaction temperature of the conversion of the dopant into the corresponding oxide, introducing, into a second reaction zone, a flow from the first reaction zone and oxygen, steam, or both into a reaction mixture such that oxygen, steam, or both is present in an amount to convert the dopant into a doping component, wherein the temperature in the second reaction zone is from 300 to 2000° C., doping the metal oxide particles with the doping component to obtain doped metal oxide particles, cooling the doped metal oxide particles, and separating the doped metal oxide particles from the carrier gas to isolate the doped metal oxide particles, wherein the doping component is exclusively present on the surface of the doped metal oxide particles in the form of domains, and the content of the doping component is from 10 ppm to 10 wt %, based on the doped metal oxide particles.