Basic aluminum nitrate crystallization
US4256714A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1979 |
| Grant date | Mar 17, 1981 |
| Priority date | — |
| Expiry date | Jul 27, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01F7/66
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
There is described a process for preparing large crystals of basic aluminum nitrate (BAN) from a nitric acid feed solution containing Al.sub.2 O.sub.3 values comprising the steps of: PA1 (1) evaporating water and nitric acid from the solution in a single step evaporation performed at a temperature of between about 270.degree. and about 450.degree. F. and at a pressure of between about atmospheric and about 60 psig to produce an evaporated liquor comprising at least about 16% alumina by weight; PA1 (2) holding the evaporated liquor in a quiescent state for a period of between about 20 minutes and about two hours within the temperature range of about 270.degree. F. to about 340.degree. F.; PA1 (3) injecting water into the product of step 2, the water being added in an amount sufficient to adjust the composition of the conditioned liquor to a composition expressible as the sum of two components PA2 (1) ANN (Al.sub.2 O.sub.3.6HNO.sub.3.15H.sub.2 O or Al(NO.sub.3).sub.3.9H.sub.2 O), and PA2 (2) The desired crystal product BAN or Wiseite PA3 (a) BAN (Al.sub.2 O.sub.3.2HNO.sub.3.5H.sub.2 O or Al(OH).sub.2 NO.sub.3.2.OH.sub.2 O). or PA3 (b) Wiseite (Al.sub.2 O.sub.3.2HNO.sub.3.4H.sub.2 O o…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.