CN-122010750-A - Environment-friendly production method of benzethonium chloride with solvent recycling

CN122010750ACN 122010750 ACN122010750 ACN 122010750ACN-122010750-A

Abstract

The invention belongs to the technical field of organic synthesis, and particularly relates to an environment-friendly production method of benzethonium chloride by recycling a solvent, which comprises the following steps of (1) mixing p-tert-octylphenol, ethylene oxide and epichlorohydrin according to a mole ratio of 1 (1.2-1.5), adding the mixture into a compound solvent A, carrying out addition reaction under the action of a catalyst to obtain a reaction solution containing a chloride intermediate, wherein the compound solvent A is formed by mixing ethanol and ethyl acetate according to a volume ratio of 3-5:1, the mass of the compound solvent A is 1.2-2.0 times of the total mass of p-tert-octylphenol, ethylene oxide and epichlorohydrin, (2) quaternization reaction, (3) crude product purification, (4) solvent recovery, and (5) residue treatment. The invention adopts a composite solvent system, optimizes the multi-tower rectification recovery process, ensures that the recovery rate of the solvent can reach more than 95 percent, and realizes the closed-loop cyclic utilization of the solvent.

Inventors

LIU JIANWEI
WANG XINGJUN
XU YANWEI
DING JIANG
HUA XIAN

Assignees

潍坊汇韬化工有限公司

Dates

Publication Date: 20260512
Application Date: 20251231

Claims (10)

1. The environment-friendly production method of benzethonium chloride with the solvent recycled is characterized by comprising the following steps: (1) Adding a mixed solution of (1.2-1.5) of (1.05-1.35) of (1.2-1.35) p-tert-octylphenol, ethylene oxide and epichlorohydrin into a composite solvent A, and carrying out addition reaction under the action of a catalyst to obtain a reaction solution containing a chloride intermediate, wherein the composite solvent A is formed by mixing ethanol and ethyl acetate according to a volume ratio of (3-5) 1, and the mass of the composite solvent A is 1.2-2.0 times of the total mass of the p-tert-octylphenol, the ethylene oxide and the epichlorohydrin; (2) The quaternization reaction is carried out by mixing the reaction solution containing the chloride intermediate with N, N-dimethylbenzylamine according to a mole ratio of 1 (1.12-1.23), adding the mixture into a compound solvent B for quaternization reaction to obtain a benzethonium chloride crude product mixed solution, wherein the compound solvent B is formed by mixing isopropanol and acetone according to a volume ratio of (2-4): 1, and the mass of the compound solvent B is 1.5-2.5 times of the total mass of the chloride intermediate and the N, N-dimethylbenzylamine; (3) Crude purification, namely filtering the benzethonium chloride crude product mixed solution to obtain filtrate and filter residue, washing the filter residue, and drying to obtain benzethonium chloride pure product and washing solution; (4) Solvent recovery, namely combining the filtrate with the washing liquid, recovering the composite solvent A and the composite solvent B through a rectification separation process, and recycling the recovered solvents for the reaction of the step (1) and the step (2); (5) Residue treatment, namely treating residues generated after rectification separation to obtain industrial-grade byproducts.
2. The environment-friendly production method of benzethonium chloride with solvent recycling according to claim 1, wherein the purity of p-tert-octylphenol in the step (1) is more than or equal to 98%, the purity of ethylene oxide is more than or equal to 99.5%, and the purity of epichlorohydrin is more than or equal to 98.5%.
3. The environment-friendly production method of benzethonium chloride with solvent recycling according to claim 2, wherein the purity of the ethanol in the composite solvent A in the step (1) is more than or equal to 99%, and the purity of the ethyl acetate is more than or equal to 98%.
4. The environment-friendly production method of benzethonium chloride with cyclic utilization of solvent according to claim 3, wherein the catalyst in the step (1) is boron trifluoride diethyl ether complex, the purity is more than or equal to 98%, the catalyst dosage is 0.5% -1.5% of the mass of p-tert-octyl phenol, the addition reaction temperature is 40-60 ℃, the reaction time is 3-5h, the pH value of the system is controlled to be 3.5-4.5 in the reaction process, and hydrochloric acid is adopted to adjust the pH value.
5. The environment-friendly production method of benzethonium chloride with the cyclic utilization of the solvent according to claim 1, wherein the purity of the N, N-dimethylbenzylamine in the step (2) is more than or equal to 98 percent, the quaternization reaction temperature is 60-80 ℃, the reaction time is 4-6h, the pH value of a system is controlled to be 7.0-7.5 in the reaction process, and the pH is regulated by adopting a sodium hydroxide solution.
6. The environment-friendly production method of benzethonium chloride with solvent recycling according to claim 5, wherein the purity of isopropanol in the composite solvent B in the step (2) is more than or equal to 99%, and the purity of acetone is more than or equal to 99%.
7. The environment-friendly production method of benzethonium chloride with the cyclic utilization of the solvent according to claim 1, wherein a precise filtering membrane is adopted in the step (3), the filtering precision is 0.22-0.45 μm, the washing is carried out by adopting ethanol for gradient washing for 2-3 times, the drying temperature is 60-80 ℃, the drying time is 2-3h, and the drying pressure is 0.08-0.1MPa.
8. The environment-friendly production method of benzethonium chloride with solvent recycling according to claim 1, wherein the rectification separation process in the step (4) comprises the following specific steps: S1, combining the filtrate obtained in the step (3) with the washing liquid to obtain mixed waste liquid containing ethanol, ethyl acetate, isopropanol and acetone; S2, adding 0.1-0.3% of 2, 6-di-tert-butyl-p-cresol into the mixed waste liquid, heating to 50-60 ℃, and stirring for 30min; s3, multi-tower sequential rectification separation: controlling the temperature of the top of the first rectifying tower to be 56-58 ℃, the temperature of the bottom of the first rectifying tower to be 75-78 ℃ and the operating pressure to be 0.1MPa, distilling acetone from the top of the first rectifying tower, and collecting to obtain acetone fraction; Feeding the bottom liquid of the first rectifying tower into a second rectifying tower, controlling the temperature of the top of the second rectifying tower to be 71-72 ℃, controlling the temperature of the bottom of the second rectifying tower to be 85-90 ℃, and distilling the ethanol-ethyl acetate azeotrope from the top of the second rectifying tower under the operating pressure of 0.1 MPa; And (3) feeding the bottom liquid of the second rectifying tower into a third rectifying tower, controlling the temperature of the top of the third rectifying tower to be 81-83 ℃, controlling the temperature of the bottom of the third rectifying tower to be 95-100 ℃, operating the pressure to be 0.1MPa, distilling off isopropanol from the top of the third rectifying tower, and collecting to obtain isopropanol fraction, wherein the bottom of the third rectifying tower is rectifying residue.
9. The environment-friendly production method of benzethonium chloride with the cyclic utilization of the solvent, which is characterized in that the residue treatment in the step (5) is specifically that rectification residue and 10-20wt% sodium hydroxide solution are mixed according to the mass ratio of 1 (3-5), the mixture is reacted for 2-3 hours at 80-100 ℃, sodium salt products are obtained through filtration, industrial sodium chloride is obtained through concentration and crystallization, and the filtrate is discharged after neutralization treatment after reaching standards.
10. The environment-friendly production method of benzethonium chloride with solvent recycling according to any one of claims 1 to 9, wherein the recovered composite solvent a and composite solvent B are subjected to purity detection before recycling, recycling is performed when the solvent purity is more than or equal to 98%, and rectification and purification are performed again when the solvent purity is less than 98%.

Description

Environment-friendly production method of benzethonium chloride with solvent recycling Technical Field The invention belongs to the technical field of organic synthesis, and particularly relates to an environment-friendly production method of benzethonium chloride with solvent recycling. Background Benzisothiammonium chloride, the chemical name of which is N-benzyl-N, N-dimethyl dodecane-1-ammonium chloride, is a common quaternary ammonium salt cationic surfactant, has good sterilization, disinfection and corrosion resistance, and is widely applied to the fields of medicine, sanitation, food processing, water treatment and the like. At present, industrial production of benzethonium chloride generally adopts a multi-step synthesis process, and the core steps of ethylene oxide addition, chlorination, quaternization and the like are generally carried out, namely, firstly, phenol derivatives with tert-octyl (tert-octyl) groups (such as p-tert-octyl phenol) and epoxy compounds such as ethylene oxide, epichlorohydrin and the like are subjected to addition reaction in a solvent to generate a chloride intermediate containing a phenoxyethyl or phenoxyethoxyethyl structure, and then, the intermediate and a quaternization reagent are subjected to quaternization to generate benzethonium chloride. However, the traditional process generally adopts a single solvent (such as ethanol, isopropanol and the like) as a reaction medium, although the reaction selectivity is mainly determined by a catalyst, temperature and material proportion, the single solvent system is difficult to realize the cooperative optimization of the raw material solubility and the reaction selectivity, or the poor solubility leads to slow reaction rate or polarity mismatch to aggravate side reaction, and finally leads to increased byproduct yield, so that the product yield can be maintained at 80-83%, the purity is generally 96-97%, and the difficulty of subsequent solvent recovery and product purification is obviously increased due to the strong interaction of the byproducts and the solvent. Disclosure of Invention The invention aims to provide an environment-friendly production method of benzethonium chloride with solvent recycling, which aims to solve the technical problems in the background technology. An environment-friendly production method of benzethonium chloride with solvent recycling comprises the following steps: (1) Adding a mixed solution of (1.2-1.5) of (1.05-1.35) of (1.2-1.35) p-tert-octylphenol, ethylene oxide and epichlorohydrin into a composite solvent A, and carrying out addition reaction under the action of a catalyst to obtain a reaction solution containing a chloride intermediate, wherein the composite solvent A is formed by mixing ethanol and ethyl acetate according to a volume ratio of (3-5) 1, and the mass of the composite solvent A is 1.2-2.0 times of the total mass of the p-tert-octylphenol, the ethylene oxide and the epichlorohydrin; (2) The quaternization reaction is carried out by mixing the reaction solution containing the chloride intermediate with N, N-dimethylbenzylamine according to a mole ratio of 1 (1.12-1.23), adding the mixture into a compound solvent B for quaternization reaction to obtain a benzethonium chloride crude product mixed solution, wherein the compound solvent B is formed by mixing isopropanol and acetone according to a volume ratio of (2-4): 1, and the mass of the compound solvent B is 1.5-2.5 times of the total mass of the chloride intermediate and the N, N-dimethylbenzylamine; (3) Crude purification, namely filtering the benzethonium chloride crude product mixed solution to obtain filtrate and filter residue, washing the filter residue, and drying to obtain benzethonium chloride pure product and washing solution; (4) Solvent recovery, namely combining the filtrate with the washing liquid, recovering the composite solvent A and the composite solvent B through a rectification separation process, and recycling the recovered solvents for the reaction of the step (1) and the step (2); (5) Residue treatment, namely treating residues generated after rectification separation to obtain industrial-grade byproducts. As the optimization of the technical scheme, the purity of the p-tert-octyl phenol in the step (1) is more than or equal to 98 percent, the purity of the ethylene oxide is more than or equal to 99.5 percent, and the purity of the epichlorohydrin is more than or equal to 98.5 percent. As the optimization of the technical scheme, the purity of the ethanol in the composite solvent A in the step (1) is more than or equal to 99%, and the purity of the ethyl acetate is more than or equal to 98%. As the optimization of the technical scheme, the catalyst in the step (1) is boron trifluoride diethyl etherate, the purity is more than or equal to 98%, the catalyst dosage is 0.5% -1.5% of the mass of the p-tert-octyl phenol, the addition reaction temperature is 40-60 ℃, the reaction time is 3-5h, the pH valu