Process for manufacturing a complexing agent

Patent metadata

Field	Value
Publication number	US-11485703-B2
Application number	US-201816626026-A
Country	US
Kind code	B2
Filing date	Jun 19, 2018
Priority date	Jun 28, 2017
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

The present invention is directed towards a process for manufacturing a complexing agent, said process comprising the steps of (a) Providing a nitrile according to general formula (I a) or (I b)

With M being selected from alkali metal and hydrogen and combinations thereof, (b) Saponification with a total alkali amount of 2.5 to 2.9 mol of alkali metal hydroxide per mole of nitrile according to general formula (I a) or (I b), respectively, and a pH value in the range of from 9.5 to 11.5 at the end of step (b), (c) Adding an amount of alkali metal hydroxide so that the total alkali content is 2.9 to 3.15 moles per mole nitrile according to general formula (I a) or (I b), respectively, and (d) Allowing further conversion.

First claim

The invention claimed is:

1. A process for manufacturing a complexing agent, the process comprising:
(a) providing a nitrile according to general formula (I a) or (I b):

with M being selected from alkali metal and hydrogen and combinations thereof,
(b) saponifying with a total alkali metal hydroxide amount of 2.5 to 2.9 mol of alkali metal hydroxide per mole of nitrile according to general formula (I a) or (I b), respectively, and a pH value in the range of from 9.5 to 11.5 at the end of step (b),
(c) adding an amount of alkali metal hydroxide so that the total alkali metal hydroxide content is 2.9 to 3.15 moles per mole of nitrile according to general formula (I a) or (I b), respectively, wherein, if a total of 2.9 moles alkali metal hydroxide per mole of nitrile according to general formula (I a) or (I b) are employed by the end of step (c), the amount of alkali metal hydroxide in the respective step (b) is in the range of from 2.5 to less than 2.9 moles, and
(d) further saponifying, neutralizing, or removing ammonia.

2. The process according to claim 1 , wherein step (d) is neutralizing or saponifying.

3. The process according to claim 1 , wherein the nitrile according to formula (I b) is selected from the racemic mixture, enantiomerically pure L-(I b) and mixtures of enantiomers of (I b) in which the L-isomer prevails.

4. The process according to claim 1 , wherein the saponification in step (b) is carried out at a temperature in the range of from 25 to 200° C.

5. The process according to claim 1 , wherein the alkali metal hydroxide in step (b) or step (c) is potassium hydroxide or sodium hydroxide.

6. The process according to claim 1 , wherein the addition of alkali metal hydroxide according to step (c) is performed at a temperature in the range of from 25 to 100° C.

7. The process according to claim 1 , wherein in step (c) an amount of alkali metal hydroxide is added so that the total alkali metal hydroxide content is 2.9 to 3.0 moles per mole nitrile according to general formula (I a) or (I b), respectively.

8. The process according to claim 1 , further comprising an ammonia removal step between steps (b) and (d).

9. The process according to claim 1 , wherein said process comprises the additional step (e) of spray-drying or spray granulating the resultant complexing agent.

Assignees

• Basf Se

Inventors

• Schmidt Thomas
• Stamm Armin
• Reinoso Garcia Marta
• Mormul Verena
• Mueller Michael Klemens
• Jaekel Frank
• Manning Jeremy T

Classifications

• C07C227/26 Primary

  from compounds containing carboxyl groups by reaction with HCN, or a salt thereof, and amines, or from aminonitriles · CPC title

• C07C229/16

  to carbon atoms of hydrocarbon radicals substituted by amino or carboxyl groups, e.g. ethylenediamine-tetra-acetic acid, iminodiacetic acids · CPC title

• C11D3/33

  Amino carboxylic acids · CPC title