公开(公告)号：DE1445229A1

公开(公告)日：1968-12-12

申请号：DE1445229

申请日：1960-12-06

Applicant: BASF AG

Inventor： HANS EILBRACHT DR ,  HELMUT PFANNMUELLER DR ,  RUDI-HEINZ ROTZOLL DR ,  FRIEDRICH URBAN DR ,  WIELAND ZACHER DR

IPC: C08F10/00

Abstract: A process for removing solvent from polyethylene produced in a high pressure continuous process and from the low-pressure recycle gas comprises the steps of separating the polyethylene from the reaction mixture in a high pressure separator 10 at a pressure of more than 150 atmospheres and while maintaining a definite level of liquid therein is decompressed into a low-pressure separator 13 from which the entrained residual ethylene and solvent are led through a gas cooler 23 into a third separator 24 where the ethylene is substantially freed from solvent and led at atmospheric pressure with the remaining solvent to a countercurrent heat-exchanger 26. The ethylene separated in the high-pressure separator with the bulk of the solvent is cooled in a precooler 16, part of this is expanded and separated from the solvent in a low-temperature separator 19 and returned through said heat-exchanger 26 and a second heat-exchanger 28 to the precompressor 3 where it is mixed with fresh ethylene 1. The remainder of the ethylene from the precooler 16 is further cooled in an after-cooler 21 and supplied to the after-compressor 5 before passing to the reaction vessel 7. Solvent is removed from the system by valves 20 and 25 and enters the system by valve 31. Polyethylene is removed through valve 14.

公开(公告)号：DE1495107A1

公开(公告)日：1969-03-27

申请号：DE1495107

申请日：1962-08-29

Applicant: BASF AG

Inventor： KLAUS KINKEL DR ,  HELMUT PFANNMUELLER DR ,  PETER RODER DR ,  RUDI-HEINZ ROTZOLL DR ,  MANFRED TITTEL DR ,  FRIEDRICH URBAN DR ,  WIELAND ZACHER DR

IPC: C08F10/00 ,  C08F110/02 ,  C08F3/04

Abstract: Polyethylene of density 0.91 to 0.94 is produced by polymerization of ethylene at 150 DEG to 300 DEG C. and 1500 to 3000 atmospheres in a tubular reactor with oxygen as catalyst and in the presence of a chain transfer agent, wherein the reaction mixture is heated to 168 DEG to 174 DEG C. in the reactor and then heat is immediately extracted externally through the reactor wall by means of a coolant whose temperature does not exceed 170 DEG C., the temperature of the reaction mixture not falling below 168 DEG C. In examples, the cooling medium used is water under pressure and at 160-170 DEG C. The transfer agent may be hydrogen, a hydrocarbon, an alcohol, an ester, an acid anhydride, an aldehyde or a ketone. Sheet of good transparency may be obtained.