阅读说明：本技术 一种乙酸甘油缩丙酮酯的合成方法 (Synthetic method of acetic acid glycerol ketal ester ) 是由 李斌仁 鲁晓东 熊东路 肖增钧 徐涛 龙绪俭 杨轩 于 2020-08-13 设计创作，主要内容包括：本发明公开了一种乙酸甘油缩丙酮酯的合成方法,涉及化工合成技术领域。本发明提供的乙酸甘油缩丙酮酯的合成方法,以醋酸和甘油缩丙酮为原料在催化剂与脉冲电场(PEF)协同作用下于低温下反应生成乙酸甘油缩丙酮酯,达到在较低温度下可使催化剂达到较高的催化效率的目的。本发明提供的合成方法具有反应温度低、反应时间短、效率高,条件易控制,对环境友好,生产成本低,适合于工业化规模生产等特点。(The invention discloses a method for synthesizing glycerol acetate acetonide ester, and relates to the technical field of chemical synthesis. The synthesis method of the acetic acid glycerol ketal ester provided by the invention takes acetic acid and glycerol ketal as raw materials to react at low temperature under the synergistic effect of the catalyst and a Pulsed Electric Field (PEF) to generate the acetic acid glycerol ketal ester, thereby achieving the purpose that the catalyst can achieve higher catalytic efficiency at lower temperature. The synthesis method provided by the invention has the characteristics of low reaction temperature, short reaction time, high efficiency, easily controlled conditions, environmental friendliness, low production cost, suitability for industrial mass production and the like.)

1. A synthesis method of acetic acid glycerol acetonide ester is characterized in that acetic acid and glycerol acetonide are reacted under a pulse electric field according to a molar ratio of 1:1-6, and the dosage of a catalyst is 0.001-1% of the total mass of reactants.

2. The method of claim 1, wherein the molar ratio of acetic acid to glycerol acetonide is 1: 2-5.

3. The method of synthesizing glycerol acetonide acetate of claim 1, wherein the reaction temperature is 20-70 ℃.

4. The method of synthesizing glycerol ketal acetate of claim 3, wherein the reaction temperature is 20 to 60 ℃.

5. The method for synthesizing triacetin as claimed in claim 1, wherein the electric field intensity of the pulsed electric field is 0 to 30.0k V/cm.

6. The method of synthesizing glycerol ketal acetate of claim 5, wherein the pulse frequency of the pulsed electric field is 0.8 to 1.2 khz.

7. The method of claim 6, wherein the pulse width of the pulsed electric field is 25.0-35 μ s.

8. The method of synthesizing glycerol ketal acetate of claim 1, wherein the catalyst is an ion exchange resin catalyst.

9. The method of synthesizing triacetin acetonide ester according to claim 8, wherein the catalyst is any one of Amberlyst-15 resin, NKC-9 resin, D001cc resin, D72 resin, or 732 resin.

10. The method of claim 9, wherein the catalyst is pre-treated before use, and the pre-treatment comprises the following steps:

soaking the resin in absolute ethyl alcohol with the volume 1.5-3 times that of the resin for 3-5 h;

washing with deionized water, and activating the resin;

washing the resin with deionized water after the activation is finished until the pH of the washing liquid is the same as that of the deionized water;

drying the resin in an oven at 80 ℃ after drying the resin in the air at 30-50 ℃.

Technical Field

The invention relates to the technical field of chemical synthesis, in particular to a synthetic method of acetic acid glycerol ketal ester.

Background

Glycerol acetate acetonide is an organic compound with a bifunctional structure, and the chemical structure of the glycerol acetate acetonide is as follows:

the acetin molecules contain ether bonds, ester bonds and different alkyl groups, and based on the principle of similarity and intermiscibility, the acetin molecules can dissolve organic molecules and synthesize natural high molecular compounds and can be mutually dissolved with water or water-soluble compounds to different degrees. The solvent performance is superior to that of common solvents (such as ethyl acetate, acetone, xylene, and the like), small molecular organic matters, large molecular organic matters, synthetic and natural high molecular organic matters can be dissolved, and an azeotrope can be formed with water. Its performance is superior to glycol ether and propylene glycol ether, and it has very strong dissolving power, especially for polymer. It can improve the performance of paint and ink, reduce filming temperature, increase luster, raise the adhesion, insulating property and fastness of paint film. Therefore, it has properties which are not possessed by general organic solvents.

The synthesis method of the acetic acid glycerol acetonide is wide, and can be catalyzed and synthesized by catalysts such as sulfonic acid catalysts, molecular sieve catalysts, heteropoly acid catalysts, solid super acidic catalysts, bisulfate catalysts, ionic liquid catalysts, ion exchange resin catalysts and the like, and the synthesis methods are different in thousands of autumn.

Ion exchange resins are insoluble, high molecular weight compounds, usually spherical particles, with functional groups (active groups that exchange ions) and a network structure. In solution it can exchange its own ions with the same number of ions in solution. The ion exchange resin catalyst has the advantage of easy separation from the product and also has better catalytic activity for esterification reaction. But the application is limited due to the low use temperature.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome some defects in the background technology and provide a synthetic method of acetic glycerol ketal ester, which has high catalytic efficiency, can react at low temperature and has low production cost.

In order to solve the above problems, the present invention proposes the following technical solutions:

a synthesis method of acetic acid glycerol acetonide ester comprises reacting acetic acid and glycerol acetonide at a molar ratio of 1:1-6 under pulsed electric field, wherein the amount of catalyst is 0.001-1% of the total mass of reactants.

The reaction formula of the synthesis method of the acetic acid glycerol ketal ester provided by the invention is as follows:

the further technical proposal is that the molar ratio of acetic acid and glycerol acetonide is 1: 2-5.

The further technical proposal is that the reaction temperature is 20-70 ℃.

The further technical proposal is that the reaction temperature is 20-60 ℃.

The technical scheme is that the electric field intensity of the pulse electric field is 0-30.0 k V/cm.

The further technical proposal is that the pulse frequency of the pulse electric field is 0.8-1.2k Hz.

The further technical proposal is that the pulse width of the pulse electric field is 25.0-35 mus.

The further technical scheme is that the catalyst is an ion exchange resin catalyst.

The technical scheme is that the catalyst is any one of Amberlyst-15 resin, NKC-9 resin, D001cc resin, D72 resin and 732 resin.

The further technical scheme is that the catalyst needs to be pretreated before use, and the pretreatment process is as follows:

soaking the resin in absolute ethyl alcohol with the volume 1.5-3 times that of the resin for 3-5 h;

washing with deionized water, and activating the resin;

washing the resin with deionized water after the activation is finished until the pH of the washing liquid is the same as that of the deionized water;

drying the resin in an oven at 80 ℃ after drying the resin in the air at 30-50 ℃.

The pulse electric field is generated by a pulse electric field continuous processing system; the pulse electric field continuous processing system comprises an oscilloscope, a load resistor, a pulse generator, a processing chamber and a constant flow pump; the oscilloscope is connected with the load resistor and the pulse generator in series, and the pulse generator is arranged in the processing chamber; the constant flow pump is respectively communicated with the reaction liquid storage tank and the processing chamber, and conveys reactants in the reaction liquid storage tank to the processing chamber.

The treatment chamber is provided with an electrode made of stainless steel. In the processing chamber, the insulating material is polytetrafluoroethylene.

The volume of the chamber was 0.0212mL and the pulse waveform was a square flat wave.

In the present invention, the pulsed electric field has a great effect of promoting the esterification reaction, and the use of the pulsed electric field does not increase the concentration of the reactant and does not increase the reaction temperature. The pulse electric field influences the esterification reaction mechanism of the alcohol acid water-containing system. Mainly comprises two aspects, one is that the pulsed electric field promotes the weak electrolyte acetic acid to ionize more H⁺The formation of a tetrahedral active intermediate in the esterification reaction process is accelerated, the activation energy of the esterification reaction is reduced, and the reaction rate is increased; on the other hand, the pulse electric field destroys hydrated ions and hydrated molecular structures in the system, more free ions and molecules are exposed outside, and the collision probability among reactant molecules is increased, so that the reaction rate is increased.

Compared with the prior art, the invention can achieve the following technical effects:

the synthesis method of the acetic acid glycerol ketal ester provided by the invention takes acetic acid and glycerol ketal as raw materials to react at low temperature under the synergistic effect of the catalyst and a Pulsed Electric Field (PEF) to generate the acetic acid glycerol ketal ester, thereby achieving the purpose that the catalyst can achieve higher catalytic efficiency at lower temperature. The pulse electric field is used together with a catalyst only by applying an external electric field without increasing the concentration of reactants or raising the temperature, so that the catalytic efficiency is further improved, the reaction time is shortened, and the pulse electric field has a synergistic effect.

The synthesis method provided by the invention has the characteristics of low reaction temperature, short reaction time, high efficiency, easily controlled conditions, environmental friendliness, lower production cost, suitability for industrial mass production and the like.

Detailed Description

The technical solutions in the examples will be clearly and completely described below. It is apparent that the embodiments to be described below are only a part of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The synthesis method of the acetic glycerol ketal ester provided by the embodiment of the invention takes acetic acid and glycerol ketal as raw materials to react at low temperature under the synergistic effect of ion exchange resin and Pulsed Electric Field (PEF) to generate the acetic glycerol ketal ester.

The reaction formula of the synthesis method of the acetic acid glycerol ketal ester provided by the invention is as follows:

in other embodiments, the ion exchange resin catalyst is pretreated prior to use, the pretreatment process comprising: soaking the resin in absolute ethyl alcohol with the volume twice that of the resin for 4 hours to remove impurities and pigments in the resin; then washing with deionized water, and soaking with 5 times of dilute hydrochloric acid solution with the mass fraction of 5% -6% for 24h to activate the resin; then washing with deionized water until the pH is the same as that of the used deionized water; drying at lower temperature (such as 40 deg.C), and oven drying at 80 deg.C.

The pulse electric field is generated by a pulse electric field continuous processing system; the pulse electric field continuous processing system comprises an oscilloscope, a load resistor, a pulse generator, a processing chamber and a constant flow pump; the oscilloscope is connected with the load resistor and the pulse generator in series, and the pulse generator is arranged in the processing chamber; the constant flow pump is respectively communicated with the reaction liquid storage tank and the processing chamber, and conveys reactants in the reaction liquid storage tank to the processing chamber.

It should be noted that the pulsed electric field continuous processing system may also include some auxiliary equipment, such as digital thermometer, rotameter, constant temperature circulator, the electrode material of the processing chamber is stainless steel, the insulating part is polytetrafluoroethylene, and the capacity is 0.0212 mL. The skilled person can add or design the pulsed electric field continuous processing system according to the need; the person skilled in the art can also purchase the existing pulse generating device to generate the pulse, and as long as the parameters of the pulse electric field are controlled within the specified range of the present invention, the method provided by the present invention operates to obtain the corresponding technical effect, and all that is within the protection scope of the present invention.

In other embodiments, the pulsed electric field parameters are: the electric field intensity is 0-30.0 k V/cm, the pulse frequency is 1.0k Hz, and the pulse width is 30.0 mu s; the waveform is a flat square wave.

The following are specific embodiments: