Method of preparing zirconia-silica xerogels, the xerogels, and xerogel catalysts
US4246137A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1979 |
| Grant date | Jan 20, 1981 |
| Priority date | — |
| Expiry date | May 31, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F110/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of preparing large pore volume zirconia-silica catalyst supports, the resulting supports and a method of polymerizing olefins comprising contacting an olefin or mixture of olefins with a catalyst prepared with these supports. The supports are prepared by reacting a zirconium compound of the formula M.sub.4 Zr(C.sub.2 O.sub.4).sub.4.nH.sub.2 O, where M is an alkali metal or ammonium ion and n equals 0 to 10, with a silicon compound of the type A.sub.2 SiO.sub.3, where A is an alkali metal, in an aqueous solution at a pH equal to at least 11, then adding an acidic solution to a pH of about 5-9 to produce a hydrocogel. The hydrocogel is then aged and washed free of soluble by-products first with water, then with aqueous ammonium nitrate and again with water. The water is removed from the washed hydrocogel by azeotropic distillation or by washing with a water miscible solvent and then calcining the resulting xerocogel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.