METHOD OF PRODUCING ZWITTERIONIC SURFACTANT Russian patent published in 2024 - IPC C07C231/02 C11D1/90 C07C233/36 C07C233/38 C09K3/32 

FIELD: organic chemistry; surfactant chemistry.

SUBSTANCE: invention relates to a method of producing a zwitterionic surfactant which exhibits a thickener property and can be used in the oil industry. Method of producing a zwitterionic surfactant involves, at a first step, a reaction between dimethylaminopropylamine and lauric acid, or palmitic acid, or oleic acid, or stearic acid, or erucic acid to form fatty acid amide in molar ratio of (1–1.1):1 in the presence of orthophosphoric acid, temperature of 140–155 °C, duration of synthesis from 3 to 5 hours and at the second stage reaction between sodium salt of monochloroacetic acid and amide with formation of alkylamidopropyl betaine in molar ratio of 1:1 in a medium of isopropyl alcohol and water, temperature of 80 °C and duration of synthesis of 6 hours, wherein the first stage is carried out with ultrasonic exposure with amplitude control from 10 to 100% in a periodic cycle of pulsation: 60 seconds of exposure and 60 seconds of pause.

EFFECT: obtaining a surfactant with high output.

1 cl, 2 tbl, 11 ex