ACRYLIC ACID PRODUCTION PROCESS

• US 20170267618A1
• Filed: 03/21/2017
• Published: 09/21/2017
• Est. Priority Date: 03/21/2016
• Status: Active Grant

• Current Assignee: Novomer, Inc (Danimer Scientific, Inc.)
• Original Assignee: Novomer, Inc (Danimer Scientific, Inc.)
• Inventors: Sookraj, Sadesh H., Tseitlin, Alexander, Pokrovski, Konstantin A., Mukaddam, Waheed
• Granted Patent: US 10,662,139 B2
• Time in Patent Office: Days
• CPC Class Codes: B01J 20/267 Cross-linked polymers
• CPC Class Codes: B01J 20/3085 Chemical treatments not covered by groups B01J20/3007 - B01J20/3078
• CPC Class Codes: B01J 2208/00752 Feeding
• CPC Class Codes: B01J 29/084 Y-type faujasite
• CPC Class Codes: B01J 29/40 of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
• CPC Class Codes: B01J 4/001 Feed or outlet devices as such, e.g. feeding tubes
• CPC Class Codes: B01J 8/0278 Feeding reactive fluids for solid material B01J8/0015
• CPC Class Codes: C07C 51/09 from carboxylic acid esters or lactones
• CPC Class Codes: C07C 51/44 by distillation
• CPC Class Codes: C07C 51/50 Use of additives, e.g. for stabilisation
• CPC Class Codes: C07C 57/04 Acrylic acid; Methacrylic acid
• CPC Class Codes: C07D 305/12 Beta-lactones
• CPC Class Codes: C08F 120/06 Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
• CPC Class Codes: C08F 20/06 Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof

Abstract

Provided herein are methods of producing acrylic acid from bPL. Such methods involve the use of a heterogeneous catalyst, such as a zeolite at vapor phase conditions. The method may use a fixed bed, moving bed or fluidized contacting zone as the reactor configurations.

Claims

1. A method of producing acrylic acid from β

-propiolactone, the method comprising;

contacting β

-propiolactone with a heterogeneous catalyst comprising crystalline microporous solids under vapor phase conditions, optionally in the presence of a radical polymerization inhibitor, and

maintaining the β

-propiolactone in the vapor phase and converting at least a portion of the β

-propiolactone into acrylic acid.

2. The method of claim 1, wherein the crystalline microporous solid is a selected from the group consisting of alkaline-earth phosphates, supported phosphate salts, calcium hydroxyapatites, inorganic salts, and zeolites, or combinations thereof.

3. The method of claim 1 wherein the catalyst comprises alumina-silicate molecular sieve having Lewis and/or Brö

nsted acidity.

4. The method of claim 3 wherein the catalyst comprises a zeolite.

5. The method of claim 2 wherein the heterogeneous catalyst comprises Zeolite Y, beta Zeolite, ZSM-5, ZSM-11 ZSM-22, MCM-22, ZSM-35, Zeolite A, or combinations thereof.

6. The method of claim 2 wherein the zeolite catalyst is in a hydrogen form or in metal cation exchanged form.

7. Method of claim 6 wherein the metal cations are Na⁺, K⁺, Ca²⁺, Mg²⁺, Cu²⁺, Cu⁺.

8. The method of claim 1 wherein the heterogeneous catalyst comprises a sodium form ZSM-5 or beta zeolite having an at least 50% exchange of potassium cations with the available cation exchange sites and a silica to alumina ratio in a range of between 20 and 120.

9. The method of claim 1 wherein the radical polymerization inhibitor is phenothiazine.

10. The method of claim 1 wherein the β

-propiolactone is provided at a WHSV of between 0.1 h<sup>−

1</sup> to 2.1 h<sup>−

1</sup>.

11. The method of claim 5, wherein the β

-propiolactone is provided at a WHSV of from 0.3 h<sup>−

1</sup> to 0.9 h<sup>−

1</sup>.

12. The method of claim 1 wherein the acrylic acid produced is continuously isolated.

13. The method of claim 1 wherein the acrylic acid is produced at a yield of at least 50%.

14. The method of claim 1 wherein the acrylic acid is produced at a temperature of between 100°

C. and 300°

C.

15. The method of claim 1 wherein the β

-propiolactone, the and the catalyst are further combined with a solvent.

16. The method of claim 15, wherein the solvent comprises a polar aprotic solvent.

17. The method of claim 15, wherein the solvent comprises sulfolane.

18. The method of claim 1 wherein the acrylic acid produced has a purity of greater than 95%.

19. The method of claim 1 wherein the contacting comprises:

passing a vapor phase feed stream comprising β

-propiolactone to a fixed bed of a zeolite catalyst at conversion conditions;

recovering a product stream containing Acrylic Acid from the fixed bed; and

separating Acrylic Acid from the product stream in a separation zone.

20. The method of claim 19 wherein the conversion conditions include a pressure in a range of 200 to 20 mm Hg.

21. The method of claim 19 wherein the vapor feed stream includes the polymerization inhibitor.

22. The method of claim 19 wherein the catalyst comprises ZSM-11, ZSM-5, and ZSM-5/ZSM-11.

23. The method of claim 1 wherein the contacting comprises:

a passing vapor phase feed stream comprising β

-propiolactone to a moving bed of a catalyst comprising zeolite particles at conversion conditions;

recovering a product stream containing acrylic acid from the moving bed;

separating acrylic acid from the product stream in a separation zone; and

,

periodically withdrawing at least partially deactivated catalyst from the moving bed and replacing the deactivated catalyst with fresh catalyst having a greater activity for conversion of β

-propiolactone to acrylic acid than the catalyst withdrawn from the moving bed.

24. The method of claim 23 wherein the catalyst entering the moving bed is heated before contacting the feed stream.

25. The method of claim 23 wherein the deactivated catalyst passes to a regeneration zone where it is contacted with a regeneration gas to at least partially restore its activity and produce regenerated catalyst and at least a portion of the regenerated catalyst is returned to said moving bed as said fresh catalyst.

26. The method of claim 1 wherein the contacting comprises:

passing a vapor phase feed stream comprising β

-propiolactone into contact with a catalyst comprising zeolite particles in a fluidized reaction zone;

maintaining the catalyst particles under fluidized conditions;

disengaging a vapor phase product stream from the fluidized catalyst particles; and

,

recovering an acrylic acid product stream from the vapor phase product stream.

27. The method of claim 23 wherein the vapor phase product stream undergoes separation in at least one cyclone separator.

28. The method of claim 23 wherein the catalyst particles are maintained as a fluidized bed and the vapor phase feed stream is injected into the fluidized bed having a catalyst density of at least 25 lbs per cubic foot and the vapor phase product stream is recovered from the fluidized bed.

29. The method of claim 23 wherein the vapor phase feed stream contacts the fluidized particles in a dilute phase transfer mode wherein the dilute phase has a catalyst density of less than 20 lbs per cubic foot;

a transport gas carries the catalyst particles through the dilute phase transfer zone and the catalyst particles are disengaged from the from the transport gas at the end of the dilute phase transfer zone to recover the vapor phase product stream.

30. The method of claim 23 wherein an inert gas provides at least a portion of the fluidization gas.

31. The method of claim 23 wherein contact of the catalyst particles with the β

-propiolactone feed produces spent catalyst that contains carbon on the catalyst particles;

at least a portion of the spent catalyst particles enter a regeneration zone wherein a regeneration gas contacts the catalyst particles to remove carbon from the catalyst and produce a regenerated catalyst; and

, the regenerated catalyst if returned to the fluidized reaction zone.

32. The method of claim 23 further comprising isolating acrylic acid.

33. The method of claim 32 wherein the acrylic acid is isolated by distillation.

34. The method of claim 1 wherein the □

-propiolactone is produced from ethylene oxide and carbon monoxide.

35. A method of producing a superabsorbent polymer, comprising:

polymerizing acrylic acid produced according to the method of claim 1 in the presence of a cross-linker to produce the superabsorbent polymer.

36. A method of producing acrylic acid from β

-propiolactone, the method comprising;

passing a vapor phase feed stream comprising β

-propiolactone to a catalyst bed containing a zeolite catalyst at conversion conditions;

contacting the feed stream under vapor phase conditions in the catalyst bed; and

maintaining the β

-propiolactone in the vapor phase;

converting at least a portion of the β

-propiolactone into acrylic acid;

recovering an acrylic acid containing effluent stream from the catalyst bed; and

,

separating acrylic acid from effluent stream to recover a bPL product.

37. The method of claim 36 wherein the catalyst bed comprises a fixed bed.

38. The method of claim 37 wherein the flow of the feed steam to the catalyst bed is interrupted;

the catalyst bed receives a regeneration gas at elevated temperature to remove deactivating material from the zeolite catalyst; and

,

the passing of the feed stream to the catalyst bed is resumed.

39. The method of claim 36 wherein the catalyst bed comprises a moving catalyst bed adapted for the periodic withdrawal and replacement of catalyst;

catalyst having deactivating deposits accumulated thereon are removed from the bottom of the catalyst and fresh catalyst having a higher activity, relative to the catalyst the was removed, is added to the top of the bed replaces the volume of catalyst removed from the catalyst bed.

40. The method of claim 39 wherein the catalyst removed from the catalyst bed enters a regeneration zone;

the removed catalyst passes through the regeneration zone and contacts a regeneration gas as it passes through the regeneration zone to produce at least a portion of the fresh catalyst that replaces the spent catalyst in the catalyst bed.

41. A method of producing acrylic acid from β

-propiolactone, the method comprising;

passing a vapor phase feed stream comprising β

-propiolactone into contact with a catalyst comprising zeolite particles in a fluidized reaction zone at conversion conditions;

maintaining the β

-propiolactone in the vapor phase and maintaining the catalyst particles under fluidized conditions in the fluidization zone to convert at least a portion of the β

-propiolactone to acrylic acid;

at least partially deactivating at least a portion of the catalyst by conversion of the β

-propiolactone to acrylic acid,

disengaging a vapor phase effluent stream fluidized catalyst particles; and

,

recovering an acrylic acid product stream from the vapor phase effluent stream;

passing at least a portion of the catalyst to a regeneration zone;

at least partially restoring the activity of the catalyst by contact with a regeneration gas in the regeneration zone; and

,

passing at least a portion of the catalyst to the fluidized reaction zone.

42. The method of claim 41 wherein the catalyst is maintained as a fluidized bed and the vapor phase feed stream is injected into the fluidized bed;

the fluidized bed has a catalyst density of at least 25 lbs per cubic foot; and

, the vapor phase product stream is recovered from the fluidized bed.

43. The method of claim 41 wherein the fluidized reaction zone operates in a dilute phase transfer mode where a transfer gas carries the catalyst particles through the dilute phase transfer zone;

the dilute phase transfer zone has a catalyst density of less than 20 lbs per cubic foot; and

the catalyst particles are disengaged from the transfer gas to recover the vapor phase effluent stream.