Patent · US Expired

Twice-aged porous inorganic oxides, catalysts, and polymerization processes

US4981831A · kind A · utility

84Cited by
18References
41Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 25, 1988
Grant dateJan 1, 1991
Priority date
Expiry dateJul 25, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F10/02
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A silica-titania cogel or silica-titania-chromium tergel is first aged at a substantially neutral pH, then aged at an alkaline pH, and then spray dried or azeotrope dried to form a xerogel. Optionally, a pore-preserving agent can be added prior to drying. The cogel can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.