Preparation method of octadecyltrimethylammonium chloride_Industrial additives

Background and overview^[1]

Octadecyltrimethylammonium chloride has good compatibility with cationic, nonionic and amphoteric surfactants, has excellent penetration, softness, emulsification, antistatic, biodegradability and bactericidal properties, and is chemically stable It has good properties and is widely used in hair conditioners, fabric softeners, fiber antistatic agents, silicone oil emulsifiers, asphalt emulsifiers, organic bentonite modifiers, disinfectants, protein flocculants in the biopharmaceutical industry, and water treatment flocculants. .

Preparation^[1]

A preparation process of highly stable octadecyltrimethylammonium chloride, including the following steps:

S1. Add dimethyloctadecylamine, deionized water and ethanol into the reaction kettle in sequence, raise the temperature of the reaction kettle to 55°C, stir evenly, the stirring speed is 300 rpm, and the stirring time is 25min;

S2. Slowly add methyl chloride into the reaction kettle. The mass ratio of dimethyloctadecylamine, deionized water, ethanol and methyl chloride is 4:1:1:1. Stir evenly after the addition. , adjust the temperature of the reactor to 60°C, the pressure to less than 0.2MPa, continue to stir, the stirring speed is rpm, and the stirring time is 1.5h;

S3. When the pressure in the reaction kettle is reduced to 0.03 MPa, the reaction ends, vacuum is applied, and liquid caustic soda, ethanol and hydrogen peroxide are added in sequence. The mass ratio of liquid caustic soda, ethanol and hydrogen peroxide is 8:4:1. Stir for 20 minutes and then take samples. Detection;

S4. According to the test results, if the color is darker, add 0.5kg hydrogen peroxide into the reaction kettle; if the content of free amine and ammonium salt is greater than 1.5%, add methyl chloride; if the pH is lower than 6.5, add 1.8Kg liquid alkali and 1.8Kg ethanol;

S5. After the temperature of the reaction kettle drops below 60°C, take out the product and fill it.

References

[1] [Chinese invention] CN201811026650.8 Preparation process of highly stable octadecyltrimethylammonium chloride