Method for synthesizing and preparing bronopol by one step

A technology of bronopol and liquid bromine, which is applied in the field of one-step synthesis and preparation of bronopol, can solve the problems of low production efficiency, increased production consumption, and low product yield, so as to improve production efficiency and production capacity, and the production conditions are easy to control , The effect that the reaction conditions are easy to control

A technology of bronopol and liquid bromine, which is applied in the field of one-step synthesis and preparation of bronopol, can solve the problems of low production efficiency, increased production consumption, and low product yield, so as to improve production efficiency and production capacity, and the production conditions are easy to control , The effect that the reaction conditions are easy to control

CN102850226AActive Publication Date: 2013-01-02WEIFANG YUKAI CHEM
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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] Put 175kg of 37% formaldehyde and 600kg of 5% sodium bromide aqueous solution into a 2000L reactor, then put in 61.04kg of nitromethane, adjust the temperature to 20°C, add 125kg of 32% liquid caustic soda, dropwise add the liquid caustic soda 160 kilograms of liquid bromine, until the color of the reaction solution becomes colorless; detect bromic acid, and adjust the content of bromic acid to obtain the adjusted product below 10ppm.

[0032] Transfer the adjusted product to the distillation tower for negative pressure distillation under the conditions of pressure below -92kpa and tower top temperature of 45-60°C, control the Baume degree of the distillation product at about 51, cool down after the distillation, and release the distillation when the temperature drops to 5°C leftovers.

[0033] The distillation product was centrifuged and dried to obtain 193 kg of bronopol, yield: 97wt%, content 99wt%, formaldehyde 6ppm, cosmetic grade bromate up to standard.

Embodiment 2

[0035] Put 175 kg of 37% formaldehyde and 600 kg of 5% sodium bromide aqueous solution into a 2000L reactor, then add 61.04 kg of nitromethane, adjust the temperature to 18°C, add 135.5 kg of 31% liquid alkali dropwise within 1 hour, and drop the solution Incubate for 1 minute after alkali, add 163 kilograms of liquid bromine dropwise in 10 minutes, until the color of the reaction solution becomes colorless; detect bromic acid with reagent, adjust the content of bromic acid to below 10ppm with 30% sodium bisulfite to adjust product.

[0036] Transfer the adjusted product to the distillation tower for negative pressure distillation under the conditions of pressure below -92kpa and tower top temperature of 45-60°C, control the Baume degree of the distillation product at about 51, distill for 70 minutes, and cool down after the end, and the temperature drops to 5°C When the distillation residue is released.

[0037] The distillation product was centrifuged and dried to obtain 19...

Embodiment 3

[0039] Put 178kg of 36% formaldehyde and 600kg of 7% sodium bromide aqueous solution into a 2000L reactor, then put in 61.04kg of nitromethane, adjust the temperature to 15°C, add 140kg of 30% liquid alkali dropwise within 65 minutes, and finish adding the solution Incubate for 3 minutes after the alkali, add 161 kilograms of liquid bromine dropwise in 20 minutes, until the color of the reaction solution becomes colorless; detect bromic acid with a reagent, and adjust the content of bromic acid to below 10ppm with 30% sodium bisulfite to adjust product.

[0040] Transfer the adjusted product to the distillation tower for negative pressure distillation under the conditions of pressure below -92kpa and tower top temperature of 45-60°C, control the Baume degree of the distillation product at about 52, distill for 80 minutes, and cool down after the end, and the temperature drops to 5°C When the distillation residue is released.

[0041] The distillation product was centrifuged and...

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Abstract

The invention discloses a method for synthesizing and preparing bronopol by one step. The method comprises the steps of: (1) adding nitromethane, a formaldehyde solution and a solvent into a reaction vessel and mixing, adding liquid caustic soda into the mixture at the temperature of 0-20 DEG C, and then adding liquid bromine into the mixture until the reaction liquid is colorless, and adjusting the content of bromic acid in the reaction product to be less than 10ppm to obtain a crude product, wherein the molar ratio of nitromethane to formaldehyde in the formaldehyde solution to alkali in the caustic soda to the liquid bromine is 1:( 2.1-2.2): (1-1.1): (1-1.05); (2) putting the crude product obtained in the step (1) into a distillation tower for negative pressure distillation, so as to obtain distillation product in a tower kettle; and (3) centrifuging and drying the distillation product to obtain bronopol. The invention relates to the technical field of fine chemical engineering, and the method is short in reaction period, simple in production technology, low in production consumption and environmental pollution as well as high in product quality and yield.

Description

technical field [0001] The invention relates to the technical field of fine chemicals, in particular to a method for preparing bronopol through one-step synthesis. Background technique [0002] Bronopol (Bronopol), chemical name: 2-bromo-2-nitro-1,3-propanediol, also known as Bronopol, bronopol, bacteriostatic alcohol, Pi Lebao, etc. Bronopol is a white to pale yellow crystalline powder with a melting point of 120-123°C. It is easily soluble in water, ethanol, and propylene glycol, but insoluble in chloroform, acetone, and benzene. Bronopol is a broad-spectrum, high-efficiency, low-toxicity bactericidal preservative. It exerts antibacterial activity in a wide pH range and has a good inhibitory effect on yeast and mold, especially against Gram-positive bacteria with strong resistance. , The inhibitory effect on negative bacteria is outstanding. Because it can still maintain its antibacterial properties in cationic, nonionic surfactants and protein hydrolyzates, it is very s...

Claims

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Application Information

Patent Timeline
02 Jan 2013
Publication
CN102850226A
IPC
C07C205/26; C07C201/12
Inventors
王志祥