CN114773178A - Method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid - Google Patents
Method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid Download PDFInfo
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- CN114773178A CN114773178A CN202210432942.1A CN202210432942A CN114773178A CN 114773178 A CN114773178 A CN 114773178A CN 202210432942 A CN202210432942 A CN 202210432942A CN 114773178 A CN114773178 A CN 114773178A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/02—Preparation of carboxylic acids or their salts, halides or anhydrides from salts of carboxylic acids
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
Abstract
The invention provides a method for reacting and crystallizing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid, and belongs to the field of chemical reactions. Mixing water with first hydrochloric acid and then preheating to obtain a preheated hydrochloric acid solution; simultaneously dropwise adding a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and second hydrochloric acid into the preheated hydrochloric acid solution to obtain a reaction solution, and carrying out double decomposition reaction to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt% in the dropwise adding process; and continuously discharging the double decomposition product, and then sequentially cooling and carrying out solid-liquid separation. The invention ensures the constant content of hydrochloric acid in the reaction liquid, limits the simultaneous dropwise addition of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid sodium solution and the hydrochloric acid, improves the crystallization state of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid, enables the crystallization particles of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid to be more suitable for solid-liquid separation, and improves the quality level of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid.
Description
Technical Field
The invention relates to the technical field of chemical reaction, in particular to a method for reacting and crystallizing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
Background
3,3 ', 4, 4' -biphenyl dianhydride is an important monomer for synthesizing polyimide, the polyimide produced by using the polyimide has excellent high temperature resistance and high insulating property, is widely applied to the fields of aviation, aerospace, electromechanics and electronics, and is used as a high-end electronic material for a display screen, a 5G network equipment material and a new energy automobile material with the development of digitalization, intellectualization and touch screen, and the using amount of the polyimide is rapidly increased.
With the popularization of high-end application of 3,3 ', 4, 4' -biphenyl dianhydride, the demand for high-quality 3,3 ', 4, 4' -biphenyl dianhydride is increasing, and it is important to control and improve the quality level from the production pre-process, namely 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
The content of the product produced by preparing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid from a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution in the existing production process of 3,3 ', 4, 4' -biphenyl dianhydride can only reach 99 wt%, and the problem of low content exists.
Disclosure of Invention
In view of this, the present invention aims to provide a method for the reaction crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid. The content of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid obtained by the method provided by the invention is high.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a method for crystallizing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid by reaction, which comprises the following steps:
mixing water with first hydrochloric acid and then preheating to obtain a preheated hydrochloric acid solution;
simultaneously dropwise adding a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and second hydrochloric acid into the preheated hydrochloric acid solution to obtain a reaction solution, carrying out double decomposition reaction on the reaction solution to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt% in the dropwise adding process;
and continuously discharging the double decomposition product, and then sequentially carrying out cooling and solid-liquid separation to obtain the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
Preferably, the mass concentration of the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution is 70-90%.
Preferably, the mass ratio of the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution to the second hydrochloric acid is 1-3: 1.
Preferably, the mass concentration of the preheated hydrochloric acid solution is 1-10%.
Preferably, the temperature of the preheated hydrochloric acid solution is 80-110 ℃.
Preferably, the temperature of the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution is 60-80 ℃.
Preferably, the temperature of the second hydrochloric acid is 30-50 ℃.
Preferably, the temperature of the double decomposition reaction is 80-110 ℃.
Preferably, the final temperature of the temperature reduction is 40-80 ℃.
Preferably, the 3,3 ', 4, 4' -biphenyltetracarboxylic acid is a flaky crystal, and the water content is 10% -20%.
The invention provides a method for crystallizing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid by reaction, which comprises the following steps: mixing water with first hydrochloric acid and then preheating to obtain a preheated hydrochloric acid solution; simultaneously dropwise adding a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and second hydrochloric acid into the preheated hydrochloric acid solution to obtain a reaction solution, carrying out double decomposition reaction on the reaction solution to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt% in the dropwise adding process; and continuously discharging the double decomposition product, and then sequentially carrying out cooling and solid-liquid separation to obtain the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
The invention ensures that the content of hydrochloric acid in the reaction liquid is constant, and limits the simultaneous dropwise addition of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid sodium solution and the second hydrochloric acid, thereby not only improving the crystallization state of 3,3 ', 4, 4' -biphenyltetracarboxylic acid, and enabling the crystallization particles of 3,3 ', 4, 4' -biphenyltetracarboxylic acid to be more suitable for solid-liquid separation, and improving the quality level of 3,3 ', 4, 4' -biphenyltetracarboxylic acid, and the data of the embodiment shows that the content of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid obtained by the invention reaches more than 99.5 wt%, and the invention is suitable for industrial production; meanwhile, continuous production is realized, the concentration of hydrochloric acid in reaction liquid is reduced, the problem that the required acid needs to be added at one time when feeding is carried out in intermittent production is avoided, the content of the added acid is higher by at least 20 wt%, frequent temperature change of equipment is eliminated, the damage to reaction equipment is reduced, the cost is reduced, and the production efficiency is improved.
The method provided by the invention is simple to operate, low in cost, economic and environment-friendly, and suitable for industrial production.
Drawings
FIG. 1 is a crystal morphology of a 3,3 ', 4, 4' -biphenyltetracarboxylic acid crystal prepared in example 3 under 400-fold microscope;
FIG. 2 is a crystal morphology diagram of 3,3 ', 4, 4' -biphenyltetracarboxylic acid crystal prepared by comparative example under 400-fold microscope.
Detailed Description
The invention provides a method for reacting and crystallizing 3,3 ', 4, 4' -biphenyl tetracarboxylic acid, which comprises the following steps:
mixing water with first hydrochloric acid and then preheating to obtain a preheated hydrochloric acid solution;
simultaneously dropwise adding a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and second hydrochloric acid into the preheated hydrochloric acid solution to obtain a reaction solution, carrying out double decomposition reaction on the reaction solution to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt% in the dropwise adding process;
and continuously discharging the double decomposition product, and then sequentially carrying out cooling and solid-liquid separation to obtain the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
In the present invention, all the raw material components are commercially available products well known to those skilled in the art unless otherwise specified.
According to the invention, water and first hydrochloric acid are mixed and then preheated to obtain a preheated hydrochloric acid solution.
In the present invention, the mass concentration of the preheated hydrochloric acid solution is preferably 1% to 10%, more preferably 2% to 7%, and still more preferably 3% to 5%.
In the invention, the temperature of the preheated hydrochloric acid solution is preferably 80-110 ℃, more preferably 80-90 ℃, and further preferably 85 ℃.
The temperature rise rate of the temperature rise is not particularly limited in the present invention, and may be in a manner known to those skilled in the art.
After the preheated hydrochloric acid solution is obtained, the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and the second hydrochloric acid are simultaneously dripped into the preheated hydrochloric acid solution to obtain a reaction solution for double decomposition reaction, so as to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt%, more preferably 2-7%, and further preferably 3-5% in the dripping process.
In the present invention, the mass concentration of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid sodium solution is preferably 70% to 90%.
In the invention, the mass ratio of the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution to the second hydrochloric acid is preferably 1-3: 1, and more preferably 1-1.5: 1.
In the invention, the temperature of the 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution is preferably 60-80 ℃, and more preferably 70 ℃.
In the invention, the temperature of the second hydrochloric acid is preferably 30-50 ℃, and more preferably 40 ℃.
In the present invention, the temperature of the double decomposition reaction is preferably 80 to 110 ℃, more preferably 80 to 90 ℃, and further preferably 85 ℃.
In the present invention, the reaction equation of the metathesis reaction is shown as follows:
after a double decomposition product is obtained, the double decomposition product is continuously discharged and is sequentially subjected to temperature reduction and solid-liquid separation to obtain the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
The present invention preferably transfers the metathesis product to another equipment vessel for temperature reduction.
In the present invention, the discharge amount of the continuous discharge is preferably the sum of the dropwise addition amounts of the sodium 3,3 ', 4, 4' -biphenyltetracarboxylic acid solution and the second hydrochloric acid.
In the invention, the final temperature of the temperature reduction is preferably 40-80 ℃, more preferably 50-60 ℃, and further preferably 55 ℃. The rate of the temperature decrease is not particularly limited in the present invention.
In the present invention, the solid-liquid separation is preferably centrifugation or filtration.
In the present invention, the 3,3 ', 4, 4' -biphenyltetracarboxylic acid is preferably a flaky crystal, and the water content is preferably 10% to 20%.
In order to further illustrate the present invention, the following examples are given to describe the method for the reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to the present invention in detail, but they should not be construed as limiting the scope of the present invention.
Example 1
Adding 300Kg of pure water and 40Kg of 30 wt% of industrial hydrochloric acid into an enamel reaction tank, heating to 85 ℃, dropwise adding 70 ℃ 3,3 ', 4, 4' -biphenyl tetracarboxylic acid sodium reaction liquid according to 568L/h, dropwise adding 40 ℃ and 30 wt% hydrochloric acid solution according to 300L/h, controlling the reaction temperature to be 85 ℃, dropwise adding for 2h, transferring the reaction liquid into a cooling enamel reaction tank according to 868L/h, cooling to 55 ℃, performing solid-liquid separation by using a centrifugal machine, centrifuging the obtained 3,3 ', 4, 4' -biphenyl tetracarboxylic acid flaky crystals, wherein the water content is 15 wt%, and the content is 99.8 wt% after drying.
Example 2
310Kg of pure water and 42Kg of 30 wt% of industrial hydrochloric acid are added into an enamel reaction tank, the temperature is raised to 80 ℃, 70 ℃ 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid reaction liquid is dripped according to 570L/h, 40 ℃ and 30 wt% hydrochloric acid solution is dripped according to 290L/h, the reaction temperature is controlled to be 80 ℃, the reaction liquid is transferred into the enamel reaction tank according to 860L/h after being dripped for 2h, the temperature is lowered to 50 ℃, a centrifuge is used for solid-liquid separation, the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid flaky crystal obtained by centrifugation has the water content of 17 wt% and the content of 99.7 wt% after drying.
Example 3
290Kg of pure water and 35Kg of 30 wt% of industrial hydrochloric acid are added into an enamel reaction tank, the temperature is raised to 82 ℃, 70 ℃ 3,3 ', 4, 4' -biphenyl tetracarboxylic acid sodium reaction liquid is dripped according to 565L/h, 40 ℃ 30 wt% hydrochloric acid solution is dripped according to 295L/h, the reaction temperature is controlled to 82 ℃, the reaction liquid is transferred into the enamel reaction tank according to 860L/h after being dripped for 2h, the temperature is lowered to 52 ℃, a centrifuge is used for solid-liquid separation, the obtained 3,3 ', 4, 4' -biphenyl tetracarboxylic acid flaky crystals (the crystal morphology is shown in figure 1) are centrifuged, the water content is 13 wt%, and the content is 99.6 wt% after drying.
Comparative example
One batch of intermittent production kettles are used, raw materials are added at one time when feeding, 1000kg of industrial 30 wt% hydrochloric acid, 500kg of pure water, 3000kg of 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution are added according to the current 5-cubic reaction kettle in a workshop, the reaction temperature is 82 ℃, the temperature is reduced to 52 ℃ when the temperature is kept for 2 hours, solid-liquid separation is carried out by using a centrifugal machine, the crystal morphology of the obtained 3,3 ', 4, 4' -biphenyl tetracarboxylic acid is shown in figure 2, the content is 99.0 wt% after drying, and the discharge amount is 300 kg.
In conclusion, the content of the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid obtained by the invention reaches more than 99.5 wt%, and the method is suitable for industrial production; meanwhile, continuous production is realized, the concentration of hydrochloric acid in reaction liquid is reduced, the condition that the required acid needs to be added at one time when materials are fed in batch production is avoided, the content of the added acid is relatively high, frequent temperature change of equipment is eliminated, the damage to reaction equipment is reduced, the cost is reduced, and the production efficiency is improved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be construed as the protection scope of the present invention.
Claims (10)
1. The method for the reactive crystallization of the 3,3 ', 4, 4' -biphenyltetracarboxylic acid is characterized by comprising the following steps:
mixing water with first hydrochloric acid and then preheating to obtain a preheated hydrochloric acid solution;
simultaneously dropwise adding a 3,3 ', 4, 4' -biphenyl sodium tetracarboxylic acid solution and second hydrochloric acid into the preheated hydrochloric acid solution to obtain a reaction solution, and carrying out double decomposition reaction to obtain a double decomposition product, wherein the content of hydrochloric acid in the reaction solution is kept at 1-10 wt% in the dropwise adding process;
and continuously discharging the double decomposition product, and then sequentially carrying out cooling and solid-liquid separation to obtain the 3,3 ', 4, 4' -biphenyl tetracarboxylic acid.
2. The method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the mass concentration of the sodium 3,3 ', 4, 4' -biphenyltetracarboxylic acid solution is 70 to 90 percent.
3. The method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1 or 2, wherein the mass ratio of the sodium 3,3 ', 4, 4' -biphenyltetracarboxylic acid solution to the second hydrochloric acid is 1-3: 1.
4. The method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the mass concentration of the preheated hydrochloric acid solution is 1 to 10%.
5. The method for the reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1 or 4, wherein the temperature of the preheated hydrochloric acid solution is 80 to 110 ℃.
6. The method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the temperature of the sodium 3,3 ', 4, 4' -biphenyltetracarboxylic acid solution is 60 to 80 ℃.
7. The method for the reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1 or 6, wherein the temperature of the second hydrochloric acid is 30 to 50 ℃.
8. The method for the reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the temperature of the double decomposition reaction is 80 to 110 ℃.
9. The method for the reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the final temperature of the cooling is 40 to 80 ℃.
10. The method for reactive crystallization of 3,3 ', 4, 4' -biphenyltetracarboxylic acid according to claim 1, wherein the 3,3 ', 4, 4' -biphenyltetracarboxylic acid is a flaky crystal and has a water content of 10% to 20%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114507130A (en) * | 2022-02-09 | 2022-05-17 | 河北海力香料股份有限公司 | Purification method of 3,3',4,4' -biphenyltetracarboxylic acid |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101607894A (en) * | 2009-07-15 | 2009-12-23 | 石家庄海力精化有限责任公司 | A kind of preparation 3,3 ＇, the method for 4,4 ＇-bibenzene tetracarboxylic |
| CN110563678A (en) * | 2019-10-15 | 2019-12-13 | 上海固创化工新材料有限公司 | Preparation method of 3,3',4,4' -biphenyl tetracarboxylic dianhydride |
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- 2022-04-24 CN CN202210432942.1A patent/CN114773178A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101607894A (en) * | 2009-07-15 | 2009-12-23 | 石家庄海力精化有限责任公司 | A kind of preparation 3,3 ＇, the method for 4,4 ＇-bibenzene tetracarboxylic |
| CN110563678A (en) * | 2019-10-15 | 2019-12-13 | 上海固创化工新材料有限公司 | Preparation method of 3,3',4,4' -biphenyl tetracarboxylic dianhydride |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114507130A (en) * | 2022-02-09 | 2022-05-17 | 河北海力香料股份有限公司 | Purification method of 3,3',4,4' -biphenyltetracarboxylic acid |
| CN114507130B (en) * | 2022-02-09 | 2023-07-14 | 河北海力恒远新材料股份有限公司 | Purification method of 3,3', 4' -biphenyl tetracarboxylic acid |
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