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A kind of purification method of the primary product of guaiacol that is used for catalytic synthesis of catechol and methanol

A technology of methyl guaiacol and guaiacol, applied in ether separation/purification, dehydration of hydroxyl-containing compounds to prepare ether, organic chemistry, etc., can solve problems such as separation and purification difficulties

Active Publication Date: 2021-05-11
SHANGHAI INST OF TECH
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem of difficult separation and purification of phthalate, 6-methylguaiacol and 3-methylguaiacol in the guaiacol produced by catechol and methanol synthesis method, the purpose of the present invention To provide a method for purifying the primary guaiacol used in the catalytic synthesis of catechol and methanol

Method used

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  • A kind of purification method of the primary product of guaiacol that is used for catalytic synthesis of catechol and methanol
  • A kind of purification method of the primary product of guaiacol that is used for catalytic synthesis of catechol and methanol
  • A kind of purification method of the primary product of guaiacol that is used for catalytic synthesis of catechol and methanol

Examples

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Effect test

Embodiment 1

[0030] Example 1: Melt crystallization

[0031] Get a certain amount of first product guaiacol (the mass content of main substances is: 97.73% guaiacol, 0.64% 6-methyl guaiacol, 1.29% phthalate, 3-methyl guaiacol Wood phenol 0.29%) is placed in the crystallizer with glass jacket. The inner tube of the crystallizer has a diameter of 50mm and a height of 230mm, and an outer tube of 65mm in diameter and a height of 200mm. Heating or cooling water can be passed between the inner and outer tubes for temperature control. Raise the temperature of the crystallizer to above 28°C until the crystals are completely dissolved, then lower the temperature to 15°C at a cooling rate of 1.0°C / h, and keep the temperature for 20h. The valve at the bottom of the crystallizer is opened to discharge the uncrystallized mother liquor, and the mother liquor is used as a raw material for rectification and enrichment of guaiacol. Then heat up slowly through the jacket to sweat at a rate of 1.0°C / h, rai...

Embodiment 2

[0032] Example 2: Melt crystallization

[0033]Get a certain amount of first product guaiacol (the mass content of main substances is: 97.93% guaiacol, 0.54% 6-methyl guaiacol, 1.02% phthalate, 3-methyl guaiacol Wood phenol 0.44%) is placed in the same glass-jacketed crystallizer of Example 1, and the crystallizer is heated up to more than 28°C until the crystals are completely dissolved, then cooled to 15°C at a cooling rate of 2.0°C / h, and kept for 10h. Open the valve at the bottom of the crystallizer to release the uncrystallized mother liquor, which can be used as a raw material for distillation and enrichment of guaiacol. Then, the jacket is slowly heated to sweat at a rate of 1.0°C / h, the temperature is raised to 26°C, and the temperature is kept for 60 minutes. After sweating is over, sweat is released and sweated liquid is collected, which can be used as crystallization raw material. Rapidly raise the temperature of the crystallizer to above 28° C. to melt the crystal...

Embodiment 3

[0034] Example 3: Melt crystallization

[0035] Get a certain amount of first product guaiacol (the mass content of main substances is: 95.23% guaiacol, 1.19% 6-methyl guaiacol, 1.36% phthalate, 3-methyl guaiacol Wood phenol (0.69%) is placed in the same glass-jacketed crystallizer as Example 1, and the crystallizer is heated to above 28°C until the crystals are completely dissolved, then cooled to 5°C at a cooling rate of 3.0°C / h, and kept for 10h. Open the valve at the bottom of the crystallizer to release the uncrystallized mother liquor, which can be used as a raw material for distillation and enrichment of guaiacol. Then, the jacket is slowly heated to sweat at a rate of 3.0°C / h, the temperature is raised to 24°C, and the temperature is kept for 30 minutes. After sweating, the sweat is released and the sweating liquid is collected, which can be used as a raw material for rectification and enrichment of guaiacol. Rapidly raise the temperature of the crystallizer to above ...

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Abstract

The invention discloses a method for purifying the primary product of guaiacol, which is used for the catalytic synthesis of catechol and methanol; the primary product of guaiacol in the present invention is melted and crystallized, heated and sweated to obtain high-purity guaiacol Wood phenol; the residual mother liquor in the crystallization process and the mother liquor produced in the sweating process are collected separately, the mother liquor and raw materials with a purity higher than 90% are combined for direct crystallization, and the components with a purity lower than 90% are subjected to vacuum distillation to enrich the guaiacol Crystallization is carried out after the collection meets the requirements of crystallization; a mixture rich in phthalylene dimethyl ether is obtained by rectification under reduced pressure, and stripping treatment is carried out to obtain pure phthalylene dimethyl ether pure product. The purification process of the present invention has low energy consumption, high product quality, and low separation cost; while obtaining the main product of high-purity guaiacol, the by-product phthalate can also be obtained; the purity of the obtained guaiacol finished product can reach More than 99.5%, wherein the impurity 6-methylguaiacol and 3-methylguaiacol contents are all below 0.05%.

Description

technical field [0001] The invention belongs to the technical field of synthetic perfumes, and in particular relates to a method for purifying primary guaiacol synthesized by catalytic synthesis of catechol and methanol. Background technique [0002] Guaiacol is an important fine chemical product, which can be used as a food additive, spice, and raw material for the synthesis of vanillin and guaiacol. At present, the global annual demand reaches nearly 20,000 tons. There are mainly two synthesis methods for guaiacol, namely o-nitrochlorobenzene method and catechol method (see published patent CN101081805). Since the catechol method is relatively cleaner, there is currently a comprehensive alternative to o-nitrochlorobenzene Benzene trends. The reaction equation for the synthesis of guaiacol by catechol method is shown in figure 1 . [0003] The reaction of catechol and methanol to synthesize guaiacol is generally completed in a fixed-bed reactor under the action of an ac...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): C07C41/09C07C41/34C07C43/23C07C43/205
CPCC07C41/09C07C41/34C07C43/23C07C43/2055
Inventor 毛海舫王浩靳苗苗王朝阳姚跃良张博董芸利毛宁阳刘君
Owner SHANGHAI INST OF TECH