Process for the production of titanium dioxide, and titanium dioxide obtained thereby
US11697599B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 2022 |
| Grant date | Jul 11, 2023 |
| Priority date | — |
| Expiry date | Mar 8, 2042 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a particulate TiO2 includes supplementing metatitanic acid with an alkali compound in a quantity of 1200 ppm to 2400 ppm of alkali, with a phosphorus compound in a quantity of 0.1 wt.-% to 0.3 wt.-% by weight of P, expressed as phosphorus, and with an aluminum compound in a quantity of 1 ppm to 1000 ppm of Al, expressed as Al, to obtain a mixture. The quantity of the alkali compound, of the phosphorus compound, and of the aluminum compound are with respect to the TiO2 content. The mixture is calcined at a constant temperature of 940° C. to 1020° C. until a numerical fraction X50 of TiO2 has a primary crystallite size of at least 200 nm, to obtain a calcined mixture. The calcined mixture is cooled to obtain a cooled calcined mixture. The cooled calcined mixture is grinded to obtain the particulate TiO2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.