Alumina production by nitric acid extraction of clay
US4246239A · kind A · utility
5Cited by
13References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1979 |
| Grant date | Jan 20, 1981 |
| Priority date | — |
| Expiry date | Jul 27, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S423/16
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Alumina values are extracted from clay by the steps of pelletizing into spherical particles, calcining the pellets in a fluidized bed reactor, extracting the clay in about 30-40% nitric acid, purifying the basic aluminum nitrate produced, crystallizing aluminum nitrate nonahydrate, decomposing the nonahydrate in at least three steps, calcining the produced alumina and reconstituting the NO.sub.x gases to nitric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.