Methods for the decomposition of contaminated plastic waste

• US 10,557,011 B2
• Filed: 05/24/2019
• Issued: 02/11/2020
• Est. Priority Date: 04/19/2018
• Status: Active Grant

• Current Assignee: Novoloop Incorporated
• Original Assignee: Biocellection Inc.
• Inventors: Yao, Jia Yun, Wang, Yu Wen, Muppaneni, Tapaswy, Shrestha, Ruja, Le Roy, Jennifer, Figuly, Garret D.
• Primary Examiner(s): Tischler, Frances
• Application Number:
  US16/422,423
• Publication Number:
  US 20190322834A1
• Time in Patent Office: 263 Days
• CPC Class Codes: B09B 3/00 Destroying solid waste or transforming solid waste into something useful or harmless
• CPC Class Codes: B09B 3/40 involving thermal treatment, e.g. evaporation processes using mineral binders involving a melting or softening step B09B3/29; involving radiation B09B3/50
• CPC Class Codes: B09B 3/45 Steam treatment, e.g. supercritical water gasification or oxidation
• CPC Class Codes: B09B 3/80 involving an extraction step
• CPC Class Codes: C07C 51/27 with oxides of nitrogen or nitrogen-containing mineral acids
• CPC Class Codes: C07C 51/275 of hydrocarbyl groups
• CPC Class Codes: C07C 51/487 by treatment giving rise to chemical modification by chemisorption C07C51/47
• CPC Class Codes: C07C 55/02 Dicarboxylic acids
• CPC Class Codes: C07C 55/06 Oxalic acid
• CPC Class Codes: C07C 55/10 Succinic acid
• CPC Class Codes: C07C 55/12 Glutaric acid
• CPC Class Codes: C07C 55/14 Adipic acid
• CPC Class Codes: C07C 55/16 Pimelic acid
• CPC Class Codes: C07C 55/18 Azelaic acid
• CPC Class Codes: C07C 55/20 Sebacic acid
• CPC Class Codes: C07C 55/21 Dicarboxylic acids containing twelve carbon atoms
• CPC Class Codes: C07C 67/03 by reacting an ester group with a hydroxy group
• CPC Class Codes: C07C 67/08 by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
• CPC Class Codes: C07C 67/48 Separation; Purification; Stabilisation; Use of additives
• CPC Class Codes: C07C 69/34 Esters of acyclic saturated polycarboxylic acids having an esterified carboxyl group bound to an acyclic carbon atom
• CPC Class Codes: C07C 69/40 : Succinic acid esters
• CPC Class Codes: C07C 69/42 : Glutaric acid esters
• CPC Class Codes: C07C 69/44 : Adipic acid esters
• CPC Class Codes: C07C 69/46 : Pimelic acid esters
• CPC Class Codes: C07C 69/48 : Azelaic acid esters
• CPC Class Codes: C07C 69/50 : Sebacic acid esters
• CPC Class Codes: C08J 11/10 : by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation depolymerisation to the original monomer C07
• CPC Class Codes: C08J 11/14 : by treatment with steam or water
• CPC Class Codes: C08J 11/16 : by treatment with inorganic material C08J11/14 takes precedence
• CPC Class Codes: C08J 11/28 : by treatment with organic compounds containing nitrogen, sulfur or phosphorus
• CPC Class Codes: C08J 2323/02 : not modified by chemical after treatment
• CPC Class Codes: C08J 2323/06 : Polyethene
• CPC Class Codes: C08J 2423/06 : Polyethene

Abstract

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

Claims

1. A method for decomposing polyethylene, comprising:

a. adding polyethylene to a reaction vessel;

b. adding aqueous nitric acid (HNO₃) to the reaction vessel to give a mixture, wherein the wt. ratio of polyethylene to aqueous nitric acid is greater than 1;

10; and

c. subjecting the mixture obtained in b. to conditions effective to decompose the polyethylene to produce decomposition products, wherein the decomposition products comprise;

i. succinic acid, glutaric acid, adipic acid, pimelic acid, and azelaic acid, or the salts and esters thereof;

ii. at least one of oxalic acid, suberic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, 2-octenedioic acid, 2-nonenedioic acid, 2-decenedioic acid, and 2-undecenedioic acid, or the salts or esters thereof; and

iii. at least one of C₈-C₂₀ dicarboxylic acid substituted with a single nitro group at the 2-position, or the salts or esters thereof.

2. The method of claim 1, wherein the decomposition products in ii. comprise at least one of oxalic acid, suberic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, or the salts or esters thereof.

3. The method of claim 1, wherein the at least one C₈-C₂₀ dicarboxylic acid substituted with a single nitro group in the 2-position is 2-nitro-suberic acid, 2-nitro-azelaic acid, 2-nitro-sebacic acid, 2-nitro-undecanedioic acid, 2-nitro-dodecanedioic acid, 2-nitro-brassylic acid, 2-nitro-tetradecanedioic acid, 2-nitro-pentadecanedioic acid, 2-nitro-hexadecanedioic acid, 2-nitro-heptadecanedioic acid, 2-nitro-octadecanedioic acid, 2-nitro-nonadecanedioic acid, or nitro-icosanedioic acid, or the salts or esters thereof.

4. The method of claim 1, wherein the at least one C₈-C₂₀ dicarboxylic acid substituted with a single nitro group in the 2-position is present up to 1 wt % in the decomposition products.

5. The method of claim 1, wherein the polyethylene further comprises at least one non-plastic waste.

6. The method of claim 1, wherein the nitric acid has a concentration of 10-90 wt %.

7. The method of claim 1, wherein the nitric acid has a concentration of about 67 to about 70 wt %.

8. The method of claim 1, wherein the weight ratio of polyethylene to nitric acid is 1:

10 to 1;

100.

9. The method of claim 1, further comprising adding at least one solid e catalyst to the reaction vessel.

10. The method of claim 9, wherein the at least one solid state catalyst is a zeolite, alumina, silico-alumino-phosphate, sulfated zirconia, zinc oxide, titanium oxide, zirconium oxide, niobium oxide, iron carbonate, calcium carbide, or combinations thereof.

11. The method of claim 1, wherein the conditions effective comprise a temperature range of about 60°

C. to about 200°

C.

12. The method of claim 1, wherein the conditions effective comprise an initial pressure of 0-1000 psi.

13. The method of claim 1, wherein the conditions effective comprise a batch process with a residence time in the reaction vessel of about 1 hour to about 10 hours.

14. The method of claim 1, wherein the conditions effective comprise a batch process with a residence time in the reaction vessel of about 3 hours to about 6 hours.

15. The method of claim 1, wherein the conditions effective comprise a continuous process.

16. The method of claim 15, wherein the continuous process comprises the continuous addition of polyethylene and aqueous nitric acid to the reaction vessel and the continuous removal of decomposition products.

17. The method of claim 1, wherein the decomposition products comprise:

a. succinic acid is present in an amount of from about 5 to about 18 wt %, glutaric acid is present in an amount of from about 8 to about 28 wt %, adipic acid is present in an amount of about 10 to about 29 wt %, pimelic acid is present in an amount of about 10 to about 20 wt %, and azelaic acid is present in an amount of about 8 to about 13 wt %, and

b. if present, oxalic acid is present in an amount up to 10 wt %, if present suberic acid is present in an amount of about 9 to about 20 wt %, if present sebacic acid is present in an amount of about 1 to about 10 wt %, if present undecanedioic acid is present in an amount of about 1 to about 8 wt %, if present dodecanedioic acid is present up to about 5 wt %, if present tridecanedioic acid is present up to about 4 wt %, if present tetradecanedioic acid is present up to about 2 wt %, and if present pentadecanedioic acid is present up to about 0.4 wt %.

18. The method of claim 1, wherein the decomposition products comprise:

a. succinic acid is present in an amount of from about 10 to about 11 wt %, glutaric acid is present in an amount of from about 15 to about 18 wt %, adipic acid is present in an amount of about 16 to about 18 wt %, pimelic acid is present in an amount of about 15 to about 17 wt %, and azelaic acid is present in an amount of about 10 to about 12 wt %, and

b. if present, oxalic acid is present in an amount up to 10 wt %, if present suberic acid is present in an amount of about 13 to about 15 wt %, if present sebacic acid is present in an amount of about 5 to about 9 wt %, if present undecanedioic acid is present in an amount of about 3 to about 6 wt %, if present dodecanedioic acid is present in an amount of 1-3 wt %, if present tridecanedioic acid is present in an amount of about 0.5 to about 1.5 wt %, if present tetradecanedioic acid is present up to about 0.2 wt %, and if present pentadecanedioic acid is present up to about 0.2 wt %.

19. The method of claim 1, wherein

a. succinic acid is present in an amount of from about 5 to about 40 wt %, glutaric acid is present in an amount of from about 8 to about 27 wt %, adipic acid is present in an amount of about 10 to about 29 wt %, pimelic acid is present in an amount of about 10 to about 20 wt %, and azelaic acid is present in an amount of about 1 to about 13 wt %, or an equivalent amount of the salts or esters thereof, and

b. if present, oxalic acid is present in an amount up to 10 wt %, if present suberic acid is present in an amount of to about 4 to about 20 wt %, if present sebacic acid is present up to about 10 wt %, if present undecanedioic acid is present up to about 8 wt %, if present dodecanedioic acid is present up to about 5 wt %, if present tridecanedioic acid is present up to about 4 wt %, if present tetradecanedioic acid is present up to about 2 wt %, and if present pentadecanedioic acid is present up to about 0.4 wt %, or an equivalent amount of the salts or esters thereof.

20. The method of claim 1, wherein the conditions effective further comprise the presence of a zeolite catalyst.

21. The method of claim 1, further comprising isolating the decomposition products.

22. The method of claim 21, wherein the decomposition products are isolated by removal of insoluble products.

23. The method of claim 22, wherein the removal of insoluble products is by filtration.

24. The method of claim 22, further comprising evaporation of solvent.

25. The method of claim 24, wherein the solvent comprises nitric acid.