Plastic depolymerization using halloysite

Patent metadata

Field	Value
Publication number	US-11319424-B2
Application number	US-202017015506-A
Country	US
Kind code	B2
Filing date	Sep 9, 2020
Priority date	Sep 9, 2019
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

A method of depolymerizing plastics using a halloysite catalyst is described herein. The method reduces the energy required for the depolymerization process while achieving improved depolymerization results.

First claim

What is claimed is:

1. A method of depolymerizing plastics, comprising the steps of:
a) introducing a feedstock comprising plastic;
b) mixing the feedstock comprising plastic with a catalyst to obtain a reactant mixture; and
c) heating the reactant mixture to obtain a product;
wherein the catalyst is halloysite, and wherein the reactant mixture comprises 1-20 wt. % of the catalyst.

2. The method of claim 1 , wherein the feedstock comprising plastic is a polyolefin or a mixture of polyolefins.

3. The method of claim 1 , wherein in step c) onset temperature is reduced by 5% as compared to a depolymerization without using the catalyst.

4. The method of claim 1 , wherein in step c) the pressure in the reactor is maintained at 0-200 psi.

5. The method of claim 1 , wherein in step c) the pressure in the reactor is maintained at 5-100 psi.

6. The method of claim 1 , wherein in step c) the pressure in the reactor is maintained at 10-30 psi.

7. The method of claim 1 , wherein a depolymerization half time at 400° C. is 50 minutes or less.

8. The method of claim 1 , wherein the product in step c) comprises a liquid product.

9. The method of claim 8 , wherein a final boiling point (FBP) of 99.5 wt % is determined by ASTM D7213 simulated distillation GC method, and the FBP of the of the liquid product is at least 5° C. lower than a FBP of a liquid product from the method of claim 1 without using the catalyst.

10. The method of claim 8 , wherein a final boiling point (FBP) of 99.5 wt % as determined by ASTM D7213 simulated distillation GC method, and the FBP of the of the liquid product is at least 10° C. lower than a FBP of a liquid product from the method of claim 1 without using the catalyst.

11. The method of claim 8 , wherein a weight average molecular weight (Mw) of the liquid product is at least 5% lighter than a Mw of a liquid product from the method of claim 1 without using the catalyst.

12. The method of claim 8 , wherein a weight average molecular weight (Mw) of the liquid product is at least 10% lighter than a Mw of a liquid product from the method of claim 1 without using the catalyst.

13. A method of depolymerizing plastics, comprising the steps of:
a) introducing a feedstock comprising plastic;
b) mixing the feedstock comprising plastic with a catalyst to obtain a reactant mixture; and
c) heating the reactant mixture to obtain a product;
wherein the catalyst is halloysite, and wherein a depolymerization half time at 400° C. is 50 minutes or less.

14. The method of claim 13 , wherein the reactant mixture comprises 1-20 wt % of the catalyst.

15. The method of claim 13 , wherein the feedstock comprising plastic is a polyolefin or a mixture of polyolefins.

16. The method of claim 13 , wherein in step c) onset temperature is reduced by 5% as compared to a depolymerization without using the catalyst.

17. The method of claim 13 , wherein in step c) the pressure in the reactor is maintained at 0-200 psi.

18. The method of claim 13 , wherein the product in step c) comprises a liquid product.

19. The method of claim 18 , wherein a final boiling point (FBP) of 99.5 wt % is determined by ASTM D7213 simulated distillation GC method, and the FBP of the of the liquid product is at least 5° C. lower than a FBP of a liquid product from the method of claim 1 without using the catalyst.

20. The method of claim 18 , wherein a weight average molecular weight (Mw) of the liquid product is at least 5% lighter than a Mw of a liquid product from the method of claim 1 without using the catalyst.

Assignees

• Basell Poliolefine Italia Srl

Inventors

• Brita Diego
• Davis Sheri E
• Fraaije Volker
• Guidotti Simona
• Liguori Dario
• Nagy Sandor
• Ramage David L
• Mihan Shahram
• Smith Christopher D
• White Daniel F
• Yang Xueyong

Classifications

• Y02W30/62

  Plastics recycling; Rubber recycling · CPC title

• C08J11/16 Primary

  by treatment with inorganic material (C08J11/14 takes precedence) · CPC title

• B01J21/12

  Silica and alumina · CPC title

• C08J2323/12

  Polypropene · CPC title

• C08J2323/06

  Polyethene · CPC title