Acesulfame potassium compositions and processes for producing same

Patent metadata

Field	Value
Publication number	US-10975047-B2
Application number	US-202016984356-A
Country	US
Kind code	B2
Filing date	Aug 4, 2020
Priority date	Sep 21, 2016
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

Improved processes for producing high purity acesulfame potassium. In one embodiment, the process comprises the steps of contacting a solvent, e.g., dichloromethane, and a cyclizing agent, e.g., sulfur trioxide, to form a cyclizing agent composition and reacting an acetoacetamide salt with the cyclizing agent in the composition to form a cyclic sulfur trioxide adduct. The contact time is less than 60 minutes. The process also comprises forming from the cyclic sulfur trioxide adduct composition a finished acesulfame potassium composition comprising non-chlorinated, e.g., non-chlorinated, acesulfame potassium and less than 35 wppm 5-halo acesulfame potassium, preferably less than 5 wppm.

First claim

We claim:

1. A process for producing a finished acesulfame potassium composition, the process comprising:
(a) providing a solvent at an initial temperature and a cyclizing agent at an initial temperature, wherein the cyclizing agent includes sulfur trioxide;
(b) contacting the solvent and the cyclizing agent to form a cyclizing agent composition;
(c) reacting an acetoacetamide salt with the cyclizing agent composition to form a cyclic sulfur trioxide adduct, wherein prior to being reacted with the acetoacetamide salt, the cyclizing agent composition has a temperature that is lower than the initial temperature of the cyclizing agent and/or the initial temperature of the solvent; and
(d) hydrolyzing the cyclic sulfur trioxide adduct to form an acesulfame-H composition comprising acesulfame-H, neutralizing the acesulfame-H in the acesulfame-H composition to form a crude acesulfame potassium composition comprising non-chlorinated acesulfame potassium, forming a finished acesulfame potassium composition from the crude acesulfame potassium composition comprising non-chlorinated acesulfame potassium and less than 35 wppm 5-chloro-acesulfame potassium;
wherein the contact time from the beginning of step (b) to the beginning of step (c) is less than 60 minutes.

2. The process of claim 1 , wherein the finished acesulfame potassium composition comprises from 0.001 wppm to 5 wppm 5-chloro-acesulfame potassium.

3. The process of claim 1 , wherein the hydrolyzing comprises adding water to the cyclic sulfur trioxide adduct to form a hydrolysis reaction mixture, and wherein the temperature of the hydrolysis reaction mixture is maintained at a temperature ranging from −35° C. to 0° C.

4. The process of claim 3 , wherein the finished acesulfame potassium composition comprises from 0.001 wppm to 5 wppm organic impurities.

5. The process of claim 1 , further comprising:
reacting sulfamic acid and an amine to form an amidosulfamic acid salt; and
reacting the amidosulfamic acid salt and acetoacetylating agent to form the acetoacetamide salt.

6. The process of claim 1 , wherein the finished acesulfame potassium composition comprises from 0.001 wppm to 2.7 wppm 5-chloro-acesulfame potassium.

7. The process of claim 1 , wherein the finished acesulfame potassium composition comprises from 0.001 wppm to 5 wppm organic impurities.

8. The process of claim 1 , wherein the finished acesulfame potassium composition comprises from 0.001 wppm to 5 wppm heavy metals.

9. The process of claim 1 , wherein the cyclizing agent composition comprises less than 1 wt % of compounds selected from chloromethyl chlorosulfate, methyl-bis-chlorosulfate, and mixtures thereof.

10. The process of claim 1 , wherein the reacting is conducted for a cyclization reaction time, from the start of a reactant feed to the end of the reactant feed, of less than 35 minutes.

11. The process of claim 1 , wherein the weight ratio of solvent to cyclizing agent in the cyclizing agent composition is at least 1:1.

12. The process of claim 1 , wherein the solvent comprises dichloromethane.

13. A finished acesulfame potassium composition produced from the process of claim 1 .

14. The finished acesulfame potassium composition of claim 13 , comprising:
non-chlorinated acesulfame potassium;
from 0.001 wppm to 2.7 wppm 5-chloro acesulfame potassium; and
from 0.001 wppm to 5 wppm heavy metals.

15. The finished acesulfame potassium composition of claim 13 , wherein the finished composition contains less than 37 wppm acetoacetamide-N-sulfonic acid.

16. The finished acesulfame potassium composition of claim 13 , wherein the finished composition contains from 0.001 wppm to 5 wppm organic impurities and from 0.001 wppm to 5 wppm of at least one heavy metal.

17. The finished acesulfame potassium composition of claim 16 , wherein the heavy metal is selected from the group consisting of mercury, lead and mixtures thereof.

18. The finished acesulfame potassium composition of claim 17 , wherein mercury is present in the finished composition in an amount of 1 wppb to 20 wppm.

19. The finished acesulfame potassium composition of claim 17 , wherein lead is present in the finished composition in an amount of 1 wppb to 25 wppm.

20. The process of claim 1 , wherein the temperature of the cyclizing agent composition is at least 2° C. lower than the initial temperature of the solvent and/or the initial temperature of the cyclizing agent.

21. The process of claim 1 , further comprising cooling the cyclizing agent composition.

22. The process of claim 21 , wherein the cyclizing agent composition is cooled to a temperature of less than 35° C.

23. The process of claim 21 , wherein the cyclizing agent composition is cooled to a temperature of less than 15° C.

24. The process of claim 1 , further comprising cooling the solvent prior to contact with the cyclizing agent.

25. The process of claim 24 , wherein the solvent is cooled to a temperature that is at least 2° C. less than the initial temperature of the solvent.

26. The process of claim 24 , wherein the solvent is cooled to a temperature of less than 35° C.

27. The process of claim 24 , wherein the solvent is cooled to a temperature of less than 15° C.

28. The process of claim 1 , further comprising cooling the cyclizing agent prior to contact with the solvent.

29. The process of claim 28 , wherein the cyclizing agent is cooled to a temperature that is at least 2° C. less than the initial temperature of the cyclizing agent.

30. The process of claim 28 , wherein the cyclizing agent is cooled to a temperature of less than 35° C.

31. The process of claim 28 , wherein the cyclizing agent is cooled to a temperature of less than 15° C.

32. The process of claim 1 , wherein the temperature of the cyclizing agent composition is less than 35° C. prior to reacting with the acetoacetamide salt.

33. The process of claim 1 , wherein the temperature of the cyclizing agent composition is less than 15° C. prior to reacting with the acetoacetamide salt.

34. The process of claim 1 , wherein the contact time is less than 15 minutes.

35. The process of claim 34 , wherein the temperature of the cyclizing agent composition is less than 35° C. prior to reacting with the acetoacetamide salt.

36. The process of claim 35 , wherein the finished acesulfame potassium composition comprises from 1 wppb to 5 wppm 5-chloro-acesulfame potassium.

37. The process of claim 1 , wherein the contact time is less than 5 minutes.

38. The process of claim 37 , wherein the temperature of the cyclizing agent composition is less than 35° C. prior to reacting with the acetoacetamide salt.

39. The process of claim 38 , wherein the finished acesulfame potassium composition comprises from 1 wppb to 5 wppm 5-chloro-acesulfame potassium.

40. The process of claim 1 , further comprising forming the acetoacetamide salt by a process that comprises reacting sulfamic acid and triethylamine to form an amidosulfamic acid salt, and reacting the amidosulfamic acid salt and a diketene to the form acetoacetamide salt.

Assignees

• Celanese Int Corp

Inventors

• Mollenkopf Christoph
• Groer Peter
• Yadav Arvind

Classifications

• C07D291/06 Primary

  Six-membered rings · CPC title

• C07C235/74

  of a saturated carbon skeleton · CPC title

• A23L27/30

  Artificial sweetening agents · CPC title

• A23V2002/00

  Food compositions, function of food ingredients or processes for food or foodstuffs · CPC title