Halogen-containing alumina catalysts prepared from alumina of at least 99% purity
US4582818A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1985 |
| Grant date | Apr 15, 1986 |
| Priority date | — |
| Expiry date | Apr 29, 2005 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J35/66
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A halogen-containing alumina catalyst for the polymerization of olefins to liquid polymers containing a major proportion of polymers having a molecular weight higher than the trimers, said catalyst selectively polymerizing isobutene from a mixture of butenes to produce liquid polyisobutene having a molecular weight higher than about 280; said catalyst containing from about 2 to about 20 wt. % chlorine, bromine or a mixture thereof, and being prepared from an alumina having a purity of at least 99% and a surface area greater than about 150 m.sup.2 /g with at least 10% of the pores having a diameter higher than about 200 .ANG.; said preparation being effected by contacting the alumina with a dry gaseous stream comprising a halogenation agent consisting essentially of volatile chlorinated and/or brominated saturated oliphatic organic compound having a vapor pressure of at least 100 mm of Hg at a temperature of 200.degree.-230.degree. C. and having a low hydrogen content, together with a non-reducing gaseous carrier at a temperature from about 230.degree. to about 300.degree. C. during a period of time t in hours such that the ratio t/R, wherein R is the mole ratio of gaseous carrier t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.