阅读说明：本技术 一种1,12-十二烷二醇的制备方法 (Preparation method of 1, 12-dodecanediol ) 是由 周明和 周兆昌 周俊 于 2019-09-03 设计创作，主要内容包括：本申请涉及医药化工技术领域,具体涉及一种1,12-十二烷二醇的制备方法。一种1,12-十二烷二醇的制备方法,该方法采用十二烷二酸与正己醇酯化反应,获得十二烷二酸二己酯,再通过加氢还原制备目标产品1,12-十二烷二醇。该方法可以不用催化剂,减少了催化剂分离步骤既可以实现酯化,减少了生产的步骤,降低了生产的成本。(The application relates to the technical field of pharmaceutical chemicals, in particular to a preparation method of 1, 12-dodecanediol. The method adopts esterification reaction of dodecanedioic acid and n-hexanol to obtain dihexyl dodecanedioic acid, and then prepares the target product 1, 12-dodecanediol through hydrogenation reduction. The method does not need catalyst, reduces the catalyst separation steps, realizes esterification, reduces the production steps and reduces the production cost.)

1. The preparation method of 1, 12-dodecanediol is characterized in that dodecanedioic acid and n-hexanol are subjected to esterification reaction to obtain dihexyl dodecanedioic acid, and the dihexyl dodecanedioic acid is subjected to hydrogenation reduction to prepare the target product 1, 12-dodecanediol.

2. The process according to claim 1, wherein n-hexanol is a by-product containing n-hexanol, wherein the by-product contains more than 20 wt% of n-hexanol and C6 monoalcohols other than n-hexanol.

3. the method of claim 1,12 ~ dodecanediol, wherein n ~ hexanol is a by ~ product of 1, 6 ~ hexanediol production, and the by ~ product comprises 30 ~ 40 wt% of n ~ hexanol and 20 ~ 30 wt% of methylcyclopentanol.

4. the method for preparing 1,12 ~ dodecanediol according to claim 1, wherein the mass ratio of dodecanedioic acid to n ~ hexanol is 1 (2 ~ 5), the reaction time is 8 ~ 12 hours, the esterification reaction temperature is 150 ~ 220 ℃, the medium ~ controlled acid value is less than 40mgKOH/g, and after the reaction is finished, the excess n ~ hexanol is removed by reduced pressure distillation to obtain dihexyl dodecanedioate.

5. the method for preparing 1,12 ~ dodecanediol according to claim 1, wherein the dihexyl dodecanedioate is subjected to catalytic hydrogenation reduction by passing through a hydrogenation reaction tower filled with a catalyst under a pressure of 1 ~ 20MPa and at a temperature of 100 ~ 220 ℃ to obtain a crude product of 1,12 ~ dodecanediol.

6. The process according to claim 6, wherein the catalyst is a supported copper catalyst.

7. The method is characterized in that dodecanedioic acid and the byproduct containing the n-hexanol are subjected to esterification reaction to obtain dihexyl dodecanedioate, 1, 12-dodecanediol is prepared by hydrogenation reduction, and the high-purity n-hexanol is obtained by hydrogenation reduction.

8. the method for separating high ~ purity n ~ hexanol from a by ~ product containing n ~ hexanol according to claim 7, wherein the dihexyl dodecanedioate is subjected to catalytic hydrogenation reduction by passing through a hydrogenation reaction tower filled with a catalyst and introducing hydrogen at a pressure of 1 ~ 20MPa and a temperature of 100 ~ 220 ℃ to obtain a crude product of 1,12 ~ dodecanediol.

9. The process of claim 8, wherein the catalyst is a supported copper based catalyst.

10. the method for separating high ~ purity n ~ hexanol from a by ~ product containing n ~ hexanol according to claim 7, wherein the esterification reaction is performed to remove excess n ~ hexanol and methylcyclopentanol by reduced pressure distillation to obtain methylcyclopentanol with a mass percentage content of 60 ~ 80%.

Technical Field

The application relates to the technical field of pharmaceutical chemicals, in particular to a preparation method of 1, 12-dodecanediol.

Background

the 1, 12-dodecanediol is used for synthesizing medicines, high-grade coatings, high-grade printing ink, high-grade resin, synthetic fiber rubber, a surfactant and the like, is white solid at normal temperature, is environment-friendly and has good chemical stability. The high carbon dibasic acid is esterified with methanol to generate high carbon dibasic ester, then hydrogenated to prepare high carbon dibasic alcohol, and finally rectified and purified to obtain pure high carbon dibasic alcohol, so that the purity of the product can be effectively improved, the generation of byproducts is reduced, the three wastes are less, and the raw materials are easy to obtain.

The Chinese patent application (publication No. CN 109678657A) discloses a method for preparing high-carbon dihydric alcohol by continuously hydrogenating high-carbon dibasic acid, which comprises the following steps:

(1) And esterification reaction: uniformly mixing high-carbon dibasic acid, a solvent and a cosolvent according to a proportion, and adding the solution into a preheater filled with a solid acid catalyst to perform an esterification reaction;

(2) And catalytic hydrogenation: mixing the material passing through the preheater with hydrogen, carrying out hydrogenation reaction in the presence of a hydrogenation catalyst, and carrying out gas-liquid separation on the reaction material after passing through a cooler to obtain a high-carbon dihydric alcohol crude product;

(3) And high-carbon polyhydric alcohol rectification: and (3) purifying the high-carbon-content dihydric alcohol crude product obtained in the step (2) by adopting a continuous rectification method to finally obtain the high-carbon-content dihydric alcohol crude product.

The Chinese patent application (publication number CN 104961627A) discloses a preparation method of 1, 10-decanediol, which comprises the following steps: adding sebacic acid, decanediol and a titanate catalyst into a dry wax esterification reaction kettle, slowly heating to 130-180 ℃ under stirring, and finishing vacuum dehydration reaction for 5-30 hours to obtain decanediol sebacate wax ester; the decanediol sebacate wax ester is subjected to reduction reaction with hydrogen under the action of a hydrogenation catalyst, the hydrogen pressure is maintained at 10.0MPa to 20.0MPa, and the hydrogen flow rate is 300m³/h～1000m³And h, generating a crude decanediol product, and distilling under high vacuum to obtain the 1, 10-decanediol.

In the method, the esterification of the high-carbon dihydric alcohol needs to be carried out by adding a catalyst, after the esterification is finished, the post-treatment is carried out, the catalyst is separated, and if the esterification is not carried out, the influence on the catalytic hydrogenation catalyst applied in the subsequent application (the poisoning of the catalyst is caused) and the product quality are influenced.

in addition, mixed C6 monohydric alcohol is co-produced in the production process of 1, 6-hexanediol, and the mixed C6 monohydric alcohol mainly comprises n-hexanol and 20-30% of methylcyclopentanol and the like.

Disclosure of Invention

in order to solve the technical problem that the catalyst needs to be separated after the esterification is finished, the first object of the application is to provide a preparation method of 1, 12-dodecanediol, which can realize the esterification without using the catalyst, reduce the catalyst separation steps, reduce the production steps and reduce the production cost. The second object of the present application is to provide a method for separating high purity n-hexanol from a by-product containing n-hexanol, which realizes separation of high purity n-hexanol from a by-product of n-hexanol, providing added value to the by-product.

In order to achieve the first object, the following technical solutions are adopted in the present application:

The method adopts esterification reaction of dodecanedioic acid and n-hexanol to obtain dihexyl dodecanedioic acid, and then prepares the target product 1, 12-dodecanediol through hydrogenation reduction of the dihexyl dodecanedioic acid.

Preferably, the n-hexanol is a by-product containing more than 20% by weight of n-hexanol and C6 monohydric alcohol except n-hexanol.

preferably, the n ~ hexanol is a by ~ product generated in the production of 1, 6 ~ hexanediol, and the by ~ product contains 30 ~ 40% of n ~ hexanol and 20 ~ 30% of methylcyclopentanol by weight percentage.

preferably, the mass ratio of the dodecanedioic acid to the n ~ hexanol is 1 (2 ~ 5), the reaction time is 8 ~ 12 hours, the esterification reaction temperature is 150 ~ 220 ℃, the medium acid value is less than 40mgKOH/g, and after the reaction is finished, the excessive n ~ hexanol is removed through reduced pressure distillation to obtain the dihexyl dodecanedioic acid.

preferably, the dihexyl dodecanedioate is subjected to catalytic hydrogenation reduction by passing through a hydrogenation reaction tower filled with a catalyst under the pressure of 1 ~ 20MPa, preferably 5 ~ 20MPa, at the temperature of 100 ~ 220 ℃ and preferably 130 ~ 220 ℃ to obtain a crude product of 1,12 ~ dodecanediol.

Preferably, the catalyst is a supported copper catalyst. The catalyst can realize lower hydrogenation pressure, lower hydrogenation temperature and lower hydrogen-ester ratio for the catalytic hydrogenation of the dihexyl dodecanedioate.

In order to achieve the second object, the following technical solutions are adopted in the present application:

The process of separating high purity n-hexanol from n-hexanol containing side product includes esterification of dodecanedioic acid with n-hexanol containing side product to obtain dihexyl dodecanedioate, hydrogenation to reduce 1, 12-dodecanediol and hydrogenation to reduce n-hexanol to obtain high purity n-hexanol.

preferably, the dihexyl dodecanedioate passes through a hydrogenation reaction tower filled with a catalyst, hydrogen is introduced, the pressure is controlled to be 1 ~ 20MPa, the temperature is controlled to be 100 ~ 220 ℃, and the catalytic hydrogenation reduction is carried out to obtain a 1,12 ~ dodecanediol crude product.

Preferably, the catalyst is a supported copper catalyst.

preferably, the esterification reaction is carried out to remove excessive byproducts of n ~ hexanol and methylcyclopentanol by reduced pressure distillation, so as to obtain methylcyclopentanol with the mass percentage content of 60 ~ 70%.

Due to the adoption of the technical scheme, the dodecanedioic acid and the n-hexanol belong to the catalyst-free esterification reaction. In the process, the n-hexanol is a reaction raw material and a good esterification water-carrying solvent, and water generated by the esterification reaction can be separated out of a reaction system, so that the esterification reaction is smoothly carried out. No catalyst is used in the esterification process, and no complex post-treatment process is needed after the esterification is finished.

The catalyst-free in this application means that the reaction can be carried out without adding an additional catalyst in general, but if a part of the catalyst is added to further increase the rate or conversion of the reaction and to facilitate separation, it should be included in this application, for example, the addition of a resin acid catalyst during esterification to further increase the rate or conversion of the reaction.

In addition, cyclopentyl alcohols in the mixed alcohol as a byproduct of n-hexanol are difficult to form esters due to steric hindrance, while n-hexanol is a straight chain and is easy to form dibasic esters. In the subsequent application, n-hexanol with the content of more than 99.0% can be separated and purified in the hydrogenation process, and methylcyclopentanol with high purity (60-70%) can be separated in the esterification process and used as perfume; can also be used as surfactant, plasticizer, etc. Thereby improving the market application added value of the byproduct n-hexanol.

the catalytic hydrogenation catalyst for the dihexyl dodecanedioate is a supported copper ~ zinc catalyst, and is a copper ~ zinc catalyst prepared by an impregnation method through improvement of a carrier, and the catalytic hydrogenation of the dihexyl dodecanedioate by the catalyst can realize lower hydrogenation pressure (1 ~ 20 MPa), lower hydrogenation temperature (100 ~ 220 ℃) and lower hydrogen ~ ester ratio.

The conversion rate of the raw material dihexyl dodecanedioate is more than or equal to 99.5%, and the selectivity of 1, 12-dodecanediol is more than or equal to 98.0%. And rectifying and purifying the crude product to obtain the target product 1, 12-dodecanediol. The purity of the product is detected to be more than or equal to 99.5 percent.

Drawings

FIG. 1 is a reaction equation of the present application.

Fig. 2 is a process flow diagram of the present application.

FIGS. 3 and 4 are the spectra of 1, 12-dodecanediol and n-hexanol prepared in example 6 of the present application.

FIGS. 5 and 6 are the spectra of 1, 12-dodecanediol and n-hexanol prepared in example 7 of the present application.

FIGS. 7 and 8 are the spectra of 1, 12-dodecanediol and n-hexanol prepared in example 8 of the present application.

FIGS. 9 and 10 are the spectra of 1, 12-dodecanediol and n-hexanol prepared in example 9 of the present application.

FIGS. 11 and 12 show the spectra of 1, 12-dodecanediol and n-hexanol prepared in example 10 of the present application.

Detailed Description

The original source of the application:

1. Dodecanedioic acid is prepared from biomass raw materials by Zhejiang Bomo New Material Co., Ltd through a fermentation method to obtain a crude product, and the crude product is refined and purified to obtain the dodecanedioic acid.

2. the byproduct n ~ hexanol is a byproduct generated in the production of 1, 6 ~ hexanediol of Zhejiang Bopolymer new materials Co., Ltd, and the n ~ hexanol content is 30 ~ 40%, and 20 ~ 30% of mixed C6 monohydric alcohol such as methylcyclopentanol.

As shown in fig. 1, the target product 1, 12-dodecanediol (shown in fig. 2) is prepared by esterification and hydrogenation reduction of dodecanedioic acid derived from biomass and byproduct n-hexanol serving as raw materials.