Borealis Technology Oy

Borealis Ag

Paul Allemeersch

Yvo Daniels

Vidar Almquist

Franciscus Jacobs

Ingrid S Melaaen

Roger Goris

Ann Kristin Lindahl

Werner Verwimp

Marc Verheijen

Erwin Vanzeir

Francisus Jacobs

Kristof Storms

Lodewijk Hendrickx

Odd Jarle Vargal

Ben Arve Olsen

Lars Tore Grimsland

Tone Aastad

Evi De Smet

Slurry polymerization process for the preparation of a polypropylene (PP) having a decaline soluble fraction (DS) of equal or below 2.5 wt.-%, wherein (a) a Ziegler-Natta catalyst (ZN), (b) propylene and optionally ethylene and/or an Cto C&#x3b1;-olefin, and (c) a diluent (D) comprising a donor agent (DA), are fed into a first reactor vessel (R1) and the polymerization of said polypropylene (PP) takes place in at least said first reactor (R1).

Process for the manufacture of isotactic polypropylene

A setting leg for a polymerization reactor connected to the lower part of the loop reactor (). A conduit () is welded to the loop reactor and leads to upper valve () and lower block valve (). Downstream of the lower block valve () is a further conduit () which leads to a lower region () and to a product take off (PTO) valve. Conduit () has a significantly greater cross-sectional area than conduit (). In use, the block valves () and () are always open to allow slurry from the reactor loop to enter the settling leg. The PTO valve () is regularly opened to allow the settled polyethylene 'fluff' to be rapidly expelled along conduit (). The greater area of conduit () significantly increases the settling rate ad polymer concentration of the polyethylene 'fluff'.

Polymerization reactor

Ths invention provides a process for the preparation of a polyethylene, in particular an HDPE suitable for blow moulding of HIC, which comprises polymerizing ethylene and, optionally an ethylenically unsaturated comonomer copolymerizable therewith, in the presence of a catalyst comprising a first silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 350 m /g and a chromium content of 0.1 to 1.0% by weight and a second silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 450 m /g and a chromium content of 0.1 to 1.0% by weight, wherein the silica support of said first catalyst also comprises alumina and the silica support of said second catalyst also comprises titanium, and preferably a co-catalyst.

Ethylene polymerization

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Tessenderlo, Belgium

Paul Allemeersch