Method for preparing a fatty amidoalkyldialkylamine
The present invent ion concerns a method for preparing a fatty amidoalkyldialkylamine by reacting a fatty acid with a dialkylaminoalkylamine, using a molar ratio of said dialkylaminoalkylamine to said fatty acid of more than 1 and up to 1.5, in the presence of Candida antarctica lipase as catalyst.
1 . A method for preparing at least one fatty amidoalkyldialkylamine by reacting at least one fatty acid containing from 8 to 24 carbon atoms with at least one dialkylaminoalkylamine of formula (I):
in which: R 1 represents a divalent alkyl group containing from 2 to 6 carbon atoms; R 2 and R 3 represent, independently of each other, monovalent alkyl groups-containing from 1 to 4 carbon atoms,
using a molar ratio of said dialkylaminoalkylamine to said fatty acid of more than 1 and up to 1.5,
in a presence of Candida antarctica lipase as a catalyst,
wherein the reaction is carried out under vacuum at a pressure ranging from 25*10 2 to 200*10 2 Pa.
2 . The method of claim 1 , wherein the at least one fatty acid contains from 10 to 20 carbon atoms.
3 . The method of claim 2 , wherein the at least one fatty acid contains from 12 to 18 carbon atoms.
4 . The method of claim 1 , wherein the at least one fatty acid is chosen from lauric acid, stearic acid, oleic acid, and mixtures thereof, as well as mixtures of fatty acids comprising from 8 to 18 carbon atoms.
5 . The method of claim 4 , wherein the at least one fatty acid is chosen from lauric acid and stearic acid.
6 . The method of claim 1 , wherein in formula (I), R 1 represents a divalent alkyl group containing 3 or 4 carbon atoms.
7 . The method of claim 1 , wherein in formula (I), the R 2 and R 3 groups are identical.
8 . The method of claim 7 , wherein in formula (I), the R 2 and R 3 groups both represent methyl groups.
9 . The method of claim 1 , wherein the dialkylaminoalkylamine of formula (I) is dimethylaminopropyl amine.
10 . The method of claim 1 , wherein the molar ratio of dialkylaminoalkylamine(s) to fatty acid(s) ranges from 1.05 to 1.3.
11 . The method of claim 10 , wherein the molar ratio of dialkylaminoalkylamine(s) to fatty acid(s) ranges from 1.1 to 1.2.
12 . The method of claim 1 , wherein the catalyst is in a form of a solid catalyst containing Candida Antarctica lipase grafted onto a polymeric support.
13 . The method of claim 12 , wherein the polymeric support is an anionic resin.
14 . The method of claim 13 , wherein the anionic resin is an acrylic resin.
15 . The method of claim 1 , wherein Candida Antarctica lipase is present in an amount ranging from 0.2 to 2% by weight, with regard to a total weight of fatty acid(s).
16 . The method of claim 15 wherein Candida Antarctica lipase is present in an amount ranging from 0.5 to 1.5% by weight, with regard to the total weight of fatty acid(s).
17 . The method of claim 1 , wherein the reaction is carried out at a temperature within the range from 75 to 120° C.
18 . The method of claim 1 , wherein the reaction is carried out in a batch reactor.
19 . The method of claim 18 , wherein after a first reaction cycle, the catalyst is recycled to the batch reactor where it is reused for a next reaction batch.