ACRYLIC ACID AND WATER-ABSORBING POLYMER STRUCTURES BASED ON RENEWABLE RAW MATERIALS AND PROCESS FOR THEIR PRODUCTION BY DEHYDRATION

• US 20090239995A1
• Filed: 08/22/2007
• Published: 09/24/2009
• Est. Priority Date: 08/22/2006
• Status: Active Grant

• Current Assignee: Evonik Superabsorber GmbH
• Original Assignee: Evonik Stockhausen GmbH (Evonik Degussa GmbH)
• Inventors: Sabbagh, Andreas, Mosler, Jürgen, Stochniol, Guido, Furno, Franck, Kuppinger, Franz-Felix, Winterberg, Markus, Bub, Günther, Latoschinski, Günter, Knippenberg, Udo, Sauer, Jörg
• Granted Patent: US 7,939,597 B2
• Time in Patent Office: Days
• US Class Current: 524/556
• CPC Class Codes: B01J 10/002 carried out in foam, aerosol or bubbles
• CPC Class Codes: B01J 19/006 Baffles
• CPC Class Codes: B01J 19/2415 Tubular reactors
• CPC Class Codes: B01J 19/32 Packing elements in the form of grids or built-up elements for forming a unit or module inside the apparatus for mass or heat transfer
• CPC Class Codes: B01J 2208/00176 outside the reactor
• CPC Class Codes: B01J 2208/0053 Controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling
• CPC Class Codes: B01J 2219/0004 Processes in series
• CPC Class Codes: B01J 2219/00081 Tubes
• CPC Class Codes: B01J 2219/00094 Jackets
• CPC Class Codes: B01J 2219/00159 controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling
• CPC Class Codes: B01J 2219/00768 vertical
• CPC Class Codes: B01J 2219/185 vertical
• CPC Class Codes: B01J 2219/1943 cylindrical
• CPC Class Codes: B01J 2219/32279 Tubes or cylinders
• CPC Class Codes: B01J 2219/32286 Grids or lattices
• CPC Class Codes: B01J 8/025 in a cylindrical shaped bed
• CPC Class Codes: B01J 8/22 gas being introduced into the liquid
• CPC Class Codes: C07C 45/52 by dehydration and rearrangement involving two hydroxy groups in the same molecule
• CPC Class Codes: C07C 47/22 Acryaldehyde; Methacryaldehyde
• CPC Class Codes: C07C 51/252 of propene, butenes, acrolein or methacrolein
• CPC Class Codes: C07C 57/04 : Acrylic acid; Methacrylic acid
• CPC Class Codes: C08F 2/00 : Processes of polymerisation
• CPC Class Codes: C08F 2/20 : with the aid of macromolecular dispersing agents
• CPC Class Codes: C08F 220/06 : Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof

Abstract

The present invention relates to a process for production of acrylic acid, comprising the steps of a) dehydration of glycerine to an acrolein-comprising dehydration product; b) gas phase oxidation of the dehydration product to obtain an acrylic acid-comprising monomer gas; c) bringing into contact of the monomer gas with a quench agent to obtain an acrylic acid-comprising quench phase; and d) work-up of the quench phase to obtain an acrylic acid-comprising monomer phase; whereby, during the dehydration a liquid phase a1 and a gas phase a2 is present, whereby in the liquid phase a1 a plurality of gas bubbles is generated, as well as a process for production of polymers by polymerisation of acrylic acid, preferably for production of water-absorbing polymers, the water-absorbing polymers obtainable by this process, a composite, a process for production of a composite, the composite obtainable by this process, and further chemical products.

Claims

1. A process for preparation of acrylic acid, comprising the following steps:

a dehydration of glycerine to an acrolein-comprising dehydration product;

b gas phase oxidation of the dehydration product to obtain an acrylic acid-comprising monomer gas;

c bringing into contact the monomer gas with a quench agent to obtain an acrylic acid-comprising quench phase; and

d work-up of the quench phase to obtain an acrylic acid-comprising monomer phase;

wherein during the dehydration of step a), a liquid phase a1 and a gas phase a2 is present, wherein in the liquid phase a1 a plurality of gas bubbles is generated.

15. The process according to any claim 2 preceding claims, wherein the dehydration occurs at a pressure in a range from about 2 to about 200 bar.

17. The process according to claim 2 preceding claims, wherein the acrolein arising from the dehydration is transferred by the plurality of gas bubble out of the liquid phase a1 into the gas phase a2.

2. A process for preparation of a polymer by polymerization of acrylic acid, comprising at least the following steps:

A dehydration of glycerine to an acrolein-comprising dehydration product;

B gas phase oxidation of the dehydration product to obtain an acrylic acid-comprising monomer gas;

C bringing into contact of the monomer gas with a quench agent to obtain an acrylic acid-comprising quench phase;

D work-up of the quench phase to obtain an acrylic acid-comprising monomer phase; and

E polymerization of the monomer phase;

wherein during the dehydration a liquid phase a1 and a gas phase a2 is present, wherein in the liquid phase a1 a plurality of gas bubbles is generated.

3. The process according to claim 2, wherein the polymer is a water-absorbing polymer structure.

4. The process according to claim 3, wherein the water-absorbing polymer structure is obtainable by a process comprising the following process steps:

i) polymerization of the acrylic acid in the presence of a crosslinker to form a polymer gel;

ii) optionally comminution of the polymer gel;

iii) drying of the optionally comminuted polymer gel to obtain water-absorbing polymer structures, and

iv) optionally surface post-treatment of the water-absorbing polymer structures.

5. The process according to claim 2 wherein the acrylic acid is present to at least about 20 mol %, based on the monomer, as a salt.

6. The process according to claim 2 wherein at least a part of the plurality of gas bubbles within the liquid phase a1 is conducted.

7. The process according to claim 2 wherein at least a part of the plurality of gas bubbles within the liquid phase a1 is divided.

8. The process according to claim 2 wherein the glycerine is obtained by saponification of fats.

9. The process according to claim 2 wherein the dehydration occurs along a path over which the glycerine concentration decreases.

10. The process according to claim 9, wherein along this path a pressure change occurs.

11. The process according to claim 10, wherein along this path different flow rates exist.

12. The process according to claim 2 wherein the glycerine is produced in the generation of liquid carburants from natural raw materials.

13. The process according to claim 2 wherein the dehydration occurs at least partially in the liquid phase.

14. The process according to claim 2 wherein the dehydration occurs at a temperature in a range from about 100 to about 400°

C.

16. The process according to claim 2 wherein the dehydration occurs with an average reactor residence time in a range from about 1 to about 30 minutes.

18-37. -37. (canceled)

38. A device for production of acrylic acid, comprising, in fluid-conducting communication with each othera dehydration reactor,a gas phase oxidation reactor,a quench unit, anda work-up unit,

wherein the dehydration reactor comprises a gas bubble generator.

39. The device for preparation of polymers, comprising, in fluid-conducting communication with each othera dehydration reactor,a gas phase oxidation reactor,a quench unit,a work-up unit, anda polymerization unit,

wherein the dehydration reactor comprises a gas bubble generator.

40-47. -47. (canceled)

48. A water-absorbing polymer structure that is based to at least about 25 wt. % on optionally partially neutralized acrylic acid, wherein the water-absorbing polymer structures are characterized by a sustainability factor of at least about 80%.

49-60. -60. (canceled)