Use of a catalyst composition for the catalytic depolymerization of plastics waste

Patent metadata

Field	Value
Publication number	US-10647922-B2
Application number	US-201616062723-A
Country	US
Kind code	B2
Filing date	Dec 15, 2016
Priority date	Dec 18, 2015
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Use of a catalyst composition comprising A) a first component containing oxidic compounds comprising aluminum and silicon with a molar ratio of silicon to aluminum of more than 1) B) a second component containing an oxidic compound of silicon wherein the ratio of the number of acidic sites of component A, determined by temperature programmed desorption with ammonia as a base, to the number of acidic sites of component B, determined under the same conditions, is at least 3: in a process for the catalytic depolymerization of plastics waste.

First claim

The invention claimed is:

1. A process comprising catalytic depolymerization of plastics waste using a catalyst composition comprising
A) a first component containing oxidic compounds comprising aluminum and silicon with a molar ratio of silicon to aluminum of more than 1, and
B) a second component containing an oxidic compound of silicon;
wherein the ratio of the number of acidic sites of component A, determined by temperature programmed desorption with ammonia as a base, to the number of acidic sites of component B, determined under the same conditions, is at least 3:1; and wherein the catalyst composition contains at least 50 wt %, based on the combined weight of components A and B, of component B.

2. The process of claim 1 wherein component A comprises supported or unsupported zeolites.

3. The process of claim 1 wherein component A) is a fresh fluid catalytic cracking catalyst, an equilibrium fluid catalytic cracking catalyst or a mixture thereof.

4. The process of claim 1 wherein the plastics waste is selected from the group consisting of post consumer waste plastics, off-spec plastics, and industrial scrap plastic.

5. The process of claim 1 wherein the plastics waste comprises at least 50 wt % of polyolefins, styrene polymers or mixtures thereof.

6. The process of claim 1 wherein the plastics waste is essentially free of thermosetting polymers.

7. The process according to claim 1 , wherein the catalyst composition contains at least 55 wt %, based on the combined weight of components A and B, of component B.

8. The process according to claim 7 , wherein the catalyst composition contains at greater than 60 wt %, based on the combined weight of components A and B, of component B.

9. A catalytic composition, comprising
A) a first component containing oxidic compounds comprising aluminum and silicon with a molar ratio of silicon to aluminum of more than 1 and
B) a second component containing an oxidic compound of silicon,
wherein the ratio of the number of acidic sites of component A, determined by temperature programmed desorption with ammonia as a base, to the number of acidic sites of component B, determined under the same conditions, is at least 3:1, and wherein the catalyst composition contains at least 50 wt %, based on the combined weight of components A and B, of component B.

10. The catalytic composition in accordance with claim 9 wherein component A) comprises supported or unsupported zeolites.

11. The catalytic composition in accordance with claim 9 wherein component A) is a fresh fluid catalytic cracking catalyst, an equilibrium fluid catalytic cracking catalyst or a mixture thereof.

12. The catalytic composition in accordance with claim 9 wherein the ratio of the number of acidic sites of component A to the number of acidic sites of component B, determined under the same conditions, is at least 5:1.

13. A process for the catalytic depolymerization of plastic waste, the process comprising
a) in a first step, introducing plastics waste into a reactor, melting the plastics waste, and thereafter increasing the temperature to a temperature in the range of from 350 to 600° C.,
b) thereafter adding, to the molten plastics, a catalytic composition comprising as component A) a fluid catalytic cracking (FCC) catalyst and as component B) a compound based on oxidic compounds of silicon, wherein the ratio of the number of acidic sites of component A to the number of acidic sites of component B is at least 3:1, and wherein the catalyst composition contains at least 50 wt %, based on the combined weight of components A and B, of component B,
c) carrying out the catalytic depolymerization at a temperature of from 350 to 600° C., and
d) recovering the product fractions formed.

14. The process in accordance with claim 13 wherein component A) is a fresh fluid catalytic cracking catalyst, an equilibrium fluid catalytic cracking catalyst or a mixture thereof.

15. The process of claim 13 wherein the plastic waste comprises at least 50 wt % of polyolefins, styrene polymers or mixtures thereof.

16. The process of claim 13 wherein the plastics waste is selected from the group consisting of post consumer waste plastics, off-spec plastics, and industrial scrap plastic.

Assignees

• Solvay

Inventors

• Streiff Stéphane
• Piccinini Marco
• Corma Avelino
• Cerro-Alarcón Miriam
• Mengual Jesús

Classifications

• C08J2323/02

  not modified by chemical after treatment · CPC title

• C08J11/16

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

• C08J2323/06

  Polyethene · CPC title

• C10G1/086

  Characterised by the catalyst used · CPC title

• C08J2323/10

  Homopolymers or copolymers of propene · CPC title