Method for producing ethylene homo-and copolymers by intensively mixing a reactive reaction component with a mobile flow medium

US6677408B1 · kind B1 · utility

Assignee

• Basell Polyolefine GmbH · DE

Inventors

• Frank-Olaf Mähling · Mannheim, DE
• Andreas Daiss · Deidesheim, DE
• Georg Groos · Schifferstadt, DE
• Andreas Wölfert · Bad Rappenau, DE

Key dates

• Filing date: Dec 6, 2001
• Grant date: Jan 13, 2004
• Expiry date: Feb 19, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F110/02
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to a method for producing ethylene homo- and copolymers in a tubular reactor at pressures above 1000 bar and temperatures in the range from 120 to 350° C. by free-radical polymerization, in which firstly small amounts of free-radical chain initiators are added to a mobile flow medium comprising ethylene, molecular weight regulator and optionally polyethylene, and the polymerization is then carried out. In accordance with the invention, the mobile flow medium is firstly split into two volume elements flowing separately from one another, the volume elements flowing separately from one another are then set in rotation in opposite directions by means of suitable flow elements, the flowing volume elements rotating in opposite directions are then recombined to form a mobile flow medium, and then, at the moment of or shortly after the combining of the flowing volume elements rotating in opposite directions, the free-radical chain initiator is fed into the sheared interfacial region between the flowing volume elements rotating in opposite directions. The invention also relates to an apparatus for carrying out this method.