Process for the recycling and cracking waste plastics based oil

Patent metadata

Field	Value
Publication number	US-12404459-B2
Application number	US-202318992282-A
Country	US
Kind code	B2
Filing date	Jul 13, 2023
Priority date	Jul 14, 2022
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

The disclosure relates to the purification and treatment of oil produced from the liquefaction of waste polymer like for instance the pyrolysis of waste plastic via the polymerization of dienes prior to further treatments.

First claim

The invention claimed is:

1. Process for a purification of liquified waste polymer comprising the following steps:
a) providing a feedstream ( 1 ) containing liquified waste polymer, wherein said feedstream ( 1 ) contains at least 0.1 wt. % to at most 80 wt. % of dienes based on the total weight of said feedstream ( 1 );
c) performing a polymerization reaction on said feedstream ( 1 ) under polymerization conditions to obtain a first product stream ( 3 ) comprising an oligomeric product ( 33 ) wherein the cationic polymerization is performed in the presence of an acidic catalyst;
d) optionally, performing a neutralization reaction by contacting said first product stream ( 3 ) with a basic compound ( 25 ) to obtain a neutralized product stream ( 4 ) and removing said basic compound from neutralized product stream ( 4 ) to obtain a second product stream ( 5 );
g) performing a separation to separate the oligomeric product ( 33 ) from the purified liquified waste polymer ( 34 ); and
k) performing a cracking reaction wherein said purified liquified waste polymer ( 34 ) is cracked on a catalyst being a 10 MR or 12 MR molecular sieve at a temperature ranging from 450° C. to 650° C., a total pressure ranging from 0.5 to 10 barg and/or with an hydrogen partial pressure ranging from 0 to 7.5 barg to crack the olefins and/or paraffins of said purified liquified waste polymer into olefins having 2 to 4 carbon atoms.

2. The process according to claim 1 is characterized in that the process further comprises a step (b) of drying the feedstream ( 1 ) to obtain a dried feedstream ( 2 ) wherein step b) is performed before step c) of polymerization so that step c) of polymerization reaction is performed on the dried feedstream ( 2 ).

3. The process according to the claim 2 is characterized in that step b) of drying is performed and comprises a sub-step b1) of decantation and/or centrifugation; with preference, the first sub-step b1) is followed by a second sub-step b2) of drying using a molecular sieve to reach a water content of less than 0.1 vol. % according to ASTM D95-13 (2018).

4. The process according to claim 1 is characterized in that the acidic catalyst is a Brönsted acid or a Lewis acid.

5. The process according to claim 1 is characterized in that the polymerization reaction in step c) is a cationic polymerization performed in the presence of an acidic catalyst being a Lewis acid chosen among BF 3 , complexes of boron trifluoride, AICl 3 , SnCl 4 , ZnCl 2 , FeCl 3 and TiCl 3 , alkyl aluminum chlorides, H 2 SO 4 or any mixture thereof; with preference, acidic catalyst is or comprises boron trifluoride etherate.

6. The process according to claim 1 is characterized in that the acidic catalyst is present at a concentration ranging from 0.5 wt. % to 5.0 wt. % based on the total weight of said feedstream ( 1 ) and/or in that the polymerization reaction of step c) is carried out until the dienes of the purified liquified waste polymer is less than 5.0 wt. % based on the total weight of the first product stream ( 3 ).

7. The process according to claim 1 is characterized in that the polymerization conditions of step (c) comprises a contact time ranging from 5 min to 5 hours; and/or a temperature ranging from 5 to 100° C. at atmospheric pressure.

8. The process according to claim 1 is characterized in that the polymerization reaction of step c) is performed in the presence of one or more comonomers; with preference, the one or more comonomers comprise a vinyl aromatic and/or the one or more comonomer are present at a concentration from 1.0 to 25.0 wt. % based on the total weight of the liquified waste polymer.

9. The process according to claim 1 is characterized in that step d) is performed and the concentration of the basic compound ranges from 0.1 to 50.0 wt. % based on the total weight of said neutralized product stream ( 4 ).

10. The process according to claim 1 is characterized in that step d) is performed and in that the basic compound:
has a pKa in water ranging from 7.5 to 14; and/or
is selected from LiOH, NaOH, CsOH, Ba(OH) 2 , Na 2 O, KOH, K 2 O, CaO, Ca(OH) 2 , MgO, Mg(OH) 2 , NH 4 OH or any mixtures thereof.

11. The process according to claim 1 is characterized in that step d) is performed in continuous mode and/or in that step d) is performed and the removal of said basic compound from neutralized product stream ( 4 ) to obtain a second product stream ( 5 ), is performed by decantation and/or a centrifugation.

12. The process according to claim 1 is characterized in that it further comprises a step e) of washing the first product stream ( 3 ) or the second product stream ( 5 ) with a solvent ( 27 ) to obtain a washed stream ( 6 ); with preference, the washing is performed at a temperature ranging from 5° C. to 95° C.

13. The process according to claim 12 is characterized in that the solvent ( 27 ) is selected from water or an aqueous acidic solution comprising one or more organic acids selected from citric acid (C 6 H 8 O 7 ), formic acid (CH 2 O 2 ), acetic acid (CH 3 COOH), sulfamic acid (H 3 NSO 3 ) and any combination thereof and/or one or more inorganic acids selected from hydrochloric acid (HCl), nitric acid (HNO 3 ), sulfuric acid (H 2 SO 4 ), phosphoric acid (H 3 PO 4 ) and any combination thereof.

14. The process according to claim 12 is characterized in that the washing is performed until the pH of said washed stream ( 6 ), is in the range of 5.0 to 9.0; and/or in that the washing is followed by a decantation and/or a centrifugation to separate the solvent from washed stream ( 6 ).

15. The process according to claim 1 is characterized in that it further comprises a step f) of filtering the stream obtained in the previous step to obtain a filtered stream ( 7 ) wherein the filtering is performed to remove solids from the first product stream ( 3 ) or from the second product stream ( 5 ) or from the washed stream ( 6 ), and/or to coalesce remaining traces of solvent if any; with preference, the filtering step is followed by a dewatering step.

16. The process according to claim 1 is characterized in that step g) of separation is performed via distillation or steam distillation or vacuum stripping or fractional distillation or any combination.

17. The process according to claim 1 is characterized in that, after the separation step g):
the oligomeric product is recovered and mixed with an elastomer, a curing agent and a filler to obtain a rubber composition or is used as a tackifying resin and mixed with an elastomer to form an adhesive composition;
the purified liquified waste polymer is recovered and blended in the fuel pool, with preference, the purified liquified waste polymer is separated in a naphtha cut having a boiling range of less than 150° C. and a diesel cut having a boiling range between 15° and 350° C. wherein said naphtha cut is incorporated in a naphtha pool, said diesel cut is incorporated in a diesel pool; and/or
the purified liquified waste polymer is recovered and is further treated either pure or diluted in a purification step h) to trap silicon and/or metals and/or phosphorous and/or halogenates over at least one trap to obtain a purified stream, wherein step h) is performed before the cracking step k) so that the cracking step k) is performed on the purified stream.

18. The process according to claim 1 is characterized in that the liquified waste polymer is a pyrolysis plastic oil, with preference, step a) of providing a feedstream ( 1 ) containing liquified waste polymer comprises the preliminary steps of preparation of l

Assignees

• Totalenergies Onetech

Inventors

• Biber Benjamin
• Richardson Christine
• Minoux Delphine
• Nelson Keith
• Adam Cindy

Classifications

• C09J121/00

  Adhesives based on unspecified rubbers · CPC title

• C08L2207/324

  Liquid component is low molecular weight polymer · CPC title

• C08L2207/20

  Recycled plastic · CPC title

• C08L21/00 Primary

  Compositions of unspecified rubbers · CPC title

• C08J11/12

  by dry-heat treatment only · CPC title