Process for Producing Acesulfame Potassium

• US 20130331565A1
• Filed: 05/24/2013
• Published: 12/12/2013
• Est. Priority Date: 06/08/2012
• Status: Active Grant

• Current Assignee: Nutrinova Netherlands BV (Mitsui & Company Limited)
• Original Assignee: Nutrinova Nutrition Specialties & Food Ingredients GmbH (Celanese Corporation)
• Inventors: Bayer, Michael J., Brietzke, Stephan, Groer, Peter, Mollenkopf, Christoph
• Granted Patent: US 9,024,016 B2
• Time in Patent Office: Days
• US Class Current: 544/2
• CPC Class Codes: A23L 27/30 Artificial sweetening agents
• CPC Class Codes: C07C 303/34 of amides of sulfuric acids
• CPC Class Codes: C07C 307/02 Monoamides of sulfuric acids or esters thereof, e.g. sulfamic acids
• CPC Class Codes: C07D 291/06 Six-membered rings

Abstract

In one embodiment, the invention relates to processes for producing acesulfame potassium. In one embodiment, the process comprises the step of reacting a first reaction mixture to form an amidosulfamic acid salt such as a trialkyl ammonium amidosulfamic acid salt. The first reaction mixture comprises sulfamic acid, an amine, and smaller amounts, if any, acetic acid, e.g., less than 1 wt % (10000 wppm). In terms of ranges, the first reaction mixture may comprise from 1 wppm to 1 wt % acetic acid. The process further comprises the step of reacting the amidosulfamic acid salt with diketene to form an acetoacetamide salt. In preferred embodiments, the amidosulfamic acid salt formation reaction is conducted at pH levels from 5.5 to 7.0. The process further comprises the step of deriving the acesulfame-K from the acetoacetamide salt.

Claims

1. A process for producing acesulfame potassium, the process comprising the steps of:

(a) reacting a first reaction mixture comprising;

sulfamic acid,

an amine, and

from 1 wppm to 1 wt % wppm acetic acid to form an amidosulfamic acid salt;

(b) reacting the amidosulfamic acid salt with diketene to form an acetoacetamide salt;

(c) deriving the acesulfame potassium from the acetoacetamide salt.

2. The process of claim 1, wherein step (c) comprises:

reacting the acetoacetamide salt with a cyclizing agent to form a cyclic sulfur trioxide adduct; and

deriving the acesulfame potassium composition from the cyclic sulfur trioxide adduct.

3. The process of claim 2, wherein the deriving comprises:

hydrolyzing the cyclic sulfur trioxide adduct to form acesulfame-H; and

neutralizing the acesulfame-H with potassium hydroxide to form the potassium acesulfame.

4. The process of claim 1, wherein a molar ratio of acetic acid to sulfamic acid in the first reaction mixture is less than 0.095:

1.

5. The process of claim 1, wherein the pH of the reaction in step (a) ranges from 5.5 to 7.0.

6. The process of claim 1, wherein the amine comprises triethylamine.

7. The process of claim 1, wherein the reaction in step (a) is conducted at an amine excess of less than 6 mol %.

8. The process of claim 1, wherein the amidosulfamic acid salt has a yellowing index less than 5 and/or the acetoacetamide salt has a yellowing index less than 45.

9. The process of claim 1, wherein the acesulfame potassium has a yellowing index less than 5.

10. The process of claim 1, wherein a molar ratio of amine to sulfamic acid in the first reaction mixture is less than 1.06:

1.

11. The process of claim 1, wherein the process does not comprise an acetic acid removal step.

12. The process of claim 1, wherein step (b) comprises:

contacting the amidosulfamic acid salt and diketene to form a second reaction mixture; and

reacting the second reaction mixture to form the acetoacetamide salt.

13. Acesulfame potassium produced from the process of claim 1.

14. An amidosulfamic acid salt produced from the process of claim 1.

15. An acetoacetamide salt produced from the process of claim 1.

16. A process for producing an amidosulfamic acid salt, the process comprising the step of:

reacting sulfamic acid, an amine and less than 10000 wppm acetic acid to form the amidosulfamic acid salt.

17. The process of claim 16, wherein the reacting is conducted at a pH ranging from 5.5 to 7.0.

18. A process for producing an acetoacetamide salt, the process comprising the steps of:

(a) reacting sulfamic acid, an amine and from 1 wppm to 10000 wppm acetic acid to form an amidosulfamic acid salt; and

(b) reacting the amidosulfamic acid salt with diketene to form the acetoacetamide salt.

19. The process of claim 18, wherein step (a) is conducted at a pH ranging from 5.5 to 7.0.

20. The process of claim 18, wherein the amidosulfamic acid salt has a yellowing index less than 5 and/or the acetoacetamide salt has a yellowing index less than 45.