High pressure depolymerization of hdpe and pp

Patent metadata

Field	Value
Publication number	US-2023106395-A1
Application number	US-202217954534-A
Country	US
Kind code	A1
Filing date	Sep 28, 2022
Priority date	Sep 30, 2021
Publication date	Apr 6, 2023
Grant date	—

Abstract

A method of depolymerizing polymeric material including the steps of: (a) feeding a polymeric material to a depolymerization reactor maintained at a temperature in the range of from 400° C. to 600° C. and operated under a pressure in the range of from 4 to 15 barg; and (b) depolymerizing at least a portion of the polymeric material thereby forming a first gaseous product and a first liquid product.

First claim

What is claimed is:

1 . A method of depolymerizing polymeric material comprising the steps of:
(a) feeding a polymeric material to a depolymerization reactor maintained at a temperature in the range of from 400° C. to 600° C. and operated under a pressure in the range of from 4 to 15 barg (58-218 psig); and (b) depolymerizing at least a portion of the polymeric material thereby forming a first gaseous product and a first liquid product, wherein the first liquid product has a composition comprising:
(i) from about 3.5 wt % to about 6.0 wt % C2-C4s;
(ii) from about 6.5 wt % to about 10.0 wt % C5s;
(iii) from about 11.7 wt % to about 15.0 wt % C6s;
(iv) from about 5.0 wt % to about 16.0 wt % C7s;
(v) from about 9.0 wt % to about 16.0 wt % C8s; and
(vi) less than about 59.5 wt % C9+.

2 . The method of depolymerizing polymeric material of claim 1 additionally comprising the step of:
(c) directing the first liquid product to a steam cracker or fluidized catalytic cracking unit wherein at least a portion of the liquid product is converted into one or more olefins.

3 . The method of depolymerizing polymeric material of claim 1 wherein when the polymeric material comprises polypropylene the first liquid product has a composition comprising:
(i) from about 3.0 wt % to about 4.5 wt % C2-C4s;
(ii) from about 7.5 wt % to about 11.5 wt % C5s;
(iii) from about 12.5 wt % to about 16.5 wt % C6s;
(iv) from about 4.2 wt % to about 6.4 wt % C7s;
(v) from about 9.0 wt % to about 13.0 wt % C8s; and
(vi) less than about 57.5 wt % C9+.

4 . The method of depolymerizing polymeric material of claim 3 wherein the polymeric material comprises at least 85 wt % polypropylene.

5 . The method of depolymerizing polymeric material of claim 1 wherein when the polymeric material comprises high density polyethylene the first liquid product has a composition comprising:
(i) from about 4.5 wt % to about 6.5 wt % C2-C4s;
(ii) from about 5.5 wt % to about 9.5 wt % C5s;
(iii) from about 11.5 wt % to about 15.5 wt % C6s;
(iv) from about 12.0 wt % to about 17.5 wt % C7s;
(v) from about 12.0 wt % to about 17.5 wt % C8s; and
(vi) less than about 50.0 wt % C9+.

6 . The method of depolymerizing polymeric material of claim 5 wherein the polymeric material comprises at least 85 wt % high density polyethylene.

7 . The method of depolymerizing polymeric material of claim 1 wherein depolymerization is conducted in the absence of a catalyst.

8 . The method of depolymerizing polymeric material of claim 1 wherein depolymerization is conducted in the absence of molecular oxygen.

9 . The method of depolymerizing polymeric material of claim 1 wherein depolymerization is conducted in an inert atmosphere.

10 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated at a temperature in the range of from 400° C. to 500° C.

11 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated at a temperature in the range of from 450° C. to 550° C.

12 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated at a temperature in the range of from 500° C. to 600° C.

13 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated under a pressure in the range of from 10 to 15 barg.

14 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated under a pressure in the range of from 6 to 12 barg.

15 . The method of depolymerizing polymeric material of claim 1 wherein the reactor is operated under a pressure in the range of from 4 to 8 barg.

16 . The method of depolymerizing polymeric material of claim 1 wherein the polymeric material is post-industrial waste polymeric material.

17 . The method of depolymerizing polymeric material of claim 1 wherein the polymeric material is post-consumer waste polymeric material.

18 . The method of depolymerizing polymeric material of claim 1 wherein the polymeric material is washed before being fed to the depolymerization reactor.

19 . The method of depolymerizing polymeric material of claim 1 wherein the polymeric material is a mixture of two or more polymeric materials.

Assignees

• Basell Poliolefine Italia Srl

Inventors

• Ramage David L
• Smith Christopher D
• Yang Xueyong
• White Daniel F
• Nagy Sandor

Classifications

• Y02P20/143

  the feedstock being recycled material, e.g. plastics · CPC title

• Y02W30/62

  Plastics recycling; Rubber recycling · CPC title

• C08J2323/06

  Polyethene · CPC title

• C08J2323/02

  not modified by chemical after treatment · CPC title

• C10G9/36

  with heated gases or vapours · CPC title