Patent · US Expired

Process for multi-step gaseous phase polymerization of olefins

US4420592A · kind A · utility

46Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 8, 1981
Grant dateDec 13, 1983
Priority date
Expiry dateOct 8, 2001

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01J2219/1946
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process for polymerizing an olefin in the gaseous phase in a multiplicity of steps in at least two independent polymerization zones connected to each other by a transfer passage, which comprises feeding an olefin and a catalyst into a first polymerization zone, polymerizing the olefin in the gaseous phase, intermittently or continuously withdrawing a gaseous stream containing the resulting polymer from the first zone and feeding it into said transfer passage, introducing the withdrawn polymer-containing gaseous stream into a second polymerization zone through the transfer passage, feeding the or an olefin into the second zone with or without feeding an additional supply of the catalyst thereinto, and polymerizing the olefin in the gaseous phase in the second zone; characterized in that an inert gas zone is provided in the transfer passage, and at least a part of the gas components of the gaseous stream containing the polymer is replaced by an inert gas.

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