High-pressure polymerization process of ethylenically unsaturated monomers in a tubular reactor

Patent metadata

Field	Value
Publication number	US-9908954-B2
Application number	US-201715674176-A
Country	US
Kind code	B2
Filing date	Aug 10, 2017
Priority date	Jul 23, 2015
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

The present technology relates to a process for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of free-radical polymerization initiators, wherein the polymerization is carried out in a continuously operated tubular reactor at temperatures from 100° C. to 350° C. and pressures from 180 MPa to 340 MPa, with a specific reactor surface area A sp of 2 m 2 /(t/h) to 5.5 m 2 /(t/h), and the tubular reactor has a specific ratio RD sp of 0.0050 MPa −1 to 0.0069 MPa −1 and an inner surface which has a surface roughness Ra of 2 μm or less.

First claim

What is claimed is:

1. A tubular reactor for polymerizing or copolymerizing ethylenically unsaturated monomers, comprising:
a length ranging from 0.5 km to 5 km, an inner diameter d i ranging from 50 mm to 120 mm, and a length-to-diameter ratio ranging from 1000 to 50000;
an inlet and at least two spatially separated initiator injection points downstream of the inlet; and
at least a portion of the length having a specific ratio RD sp ranging from 0.0050-0.0069 MPa −1 , RD sp being the ratio of an outer diameter d o to an inner diameter d i divided by a design pressure p des according to the equation:

RD
sp

=

d
o

d
i

*

p
des

.

2. The tubular reactor of claim 1 , wherein the design pressure p des of the tubular reactor ranges from 240 MPa to 400 MPa.

3. The tubular reactor of claim 1 , further comprising a pipe comprising a ratio of an outer diameter d o to an inner diameter d i ranging from 1.2 to 2.76.

4. The tubular reactor of claim 1 , further comprising an inner surface which has a surface roughness Ra of 2 μm or less, determined according to DIN EN ISO 4287:2010.

5. The tubular reactor of claim 1 , having a feed rate of reaction gas composition to the tubular reactor from 80 t/h to 210 t/h.

6. The tubular reactor of claim 1 , having a feed rate of reaction gas composition to the tubular reactor from 100 t/h to 180 t/h.

7. The tubular reactor of claim 1 , having a feed rate of reaction gas composition to the tubular reactor from 120 t/h to 160 t/h.

8. The tubular reactor of claim 1 , further comprising a tensile strength μm of at least 1100 N/mm 2 determined according to EN ISO 6892-1:2009.

9. The tubular reactor of claim 1 , having an outer diameter d o , an inner diameter d i , or an outer diameter d o and an inner diameter d i that varies over the length.

10. A process for polymerizing or copolymerizing ethylenically unsaturated monomers, comprising:
feeding a reaction gas into a tubular reactor having a specific ratio RD sp ranging from 0.0050-0.0069 MPa −1 , RD sp being the ratio of the outer diameter d o to the inner diameter d i divided by the design pressure p des according to the equation:

RD
sp

=

d
o

d
i

*

p
des

;

feeding an initiator into the tubular reactor in a concentration ranging from 0.1 mol/t to 50 mol/t; and
polymerizing the reaction gas in the tubular reactor at a temperature ranging from 100° C. to 350° C. and a pressure ranging from 180 MPa to 340 MPa.

11. The process of claim 10 , further comprising:
feeding a 30-90% by weight portion of the reaction gas to an inlet of the tubular reactor; and
feeding a 10-70% by weight portion of the reaction gas to one or more side streams of the tubular reactor downstream of the inlet of the tubular reactor.

12. The process of claim 11 , wherein the tubular reactor has an inner surface which has a surface roughness Ra of 2 μm or less, determined according to DIN EN ISO 4287:2010.

13. The tubular reactor of claim 1 , comprising at least a portion of the length having a specific ratio RD sp ranging from 0.0053 MPa −1 to 0.0066 MPa −1 .

14. The tubular reactor of claim 1 , comprising at least a portion of the length having a specific ratio RD sp ranging from 0.0056 MPa −1 to 0.0063 MPa −1 .

15. The process of claim 10 , comprising at least a portion of the tubular reactor has a specific ratio RD sp ranging from 0.0053 MPa −1 to 0.0066 MPa −1 .

16. The process of claim 10 , comprising at least a portion of the tubular reactor has a specific ratio RD sp ranging from 0.0056 MPa −1 to 0.0063 MPa −1 .

Assignees

• Basell Polyolefine Gmbh

Inventors

• Littmann Dieter
• Mohrbutter Juergen Peter
• Mei Giulia
• Finette Andre Armand
• Wolfram Sven Georg
• Deuerling Michael
• Khayrullin Danir
• Groos Georg
• Wolf Christoph

Classifications

• B01J19/2415 Primary

  Tubular reactors · CPC title

• C08F110/02 Primary

  Ethene · CPC title

• C08J2323/06

  Polyethene · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08F2/34

  Polymerisation in gaseous state · CPC title