Process for preparing hydrated alumina consisting essentially of spherical particles by homogeneous precipitation
US4902494A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1989 |
| Grant date | Feb 20, 1990 |
| Priority date | — |
| Expiry date | May 26, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/64
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for preparing hydrated alumina consisting essentially of spherical particles having a narrow granulometric distribution (polydispersion index dw/dn.ltoreq.2) starting from aqueous solution of aluminum sulphate, the molar ratio SO.sub.4.sup.= /Al.sup.3+ being greater than 1, by homogeneous precipitation in the presence of cationic polyelectrolytes, which are soluble under the reaction conditions and have a mean molecular weight higher than one million and an ionicity, deriving from the cationic groups present in the polyelectrolyte, of at least 3 milliequivalents/gram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.