Process for manufacturing titanium dioxide
US4288418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1980 |
| Grant date | Sep 8, 1981 |
| Priority date | — |
| Expiry date | Oct 29, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process is provided for the manufacture of titanium dioxide pigment wherein excess ilmenite ore is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight and in preferably at least two stages wherein the first stage is maintained at a temperature up to about 140.degree. C. and the second stage is conducted at a lower temperature (than the first stage) which is below about 100.degree. C. to provide a salt solution of titanium and iron. Thereafter, the titanium is hydrolyzed to provide titanium dioxide hydrate accompanied by recycling the spent acid from the hydrolysis for reaction with the ilmenite ore charged to the process. The titanium hydrate is calcined to provide titanium dioxide pigment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.