阅读说明：本技术 一种二元醇的合成方法 (Method for synthesizing dihydric alcohol ) 是由 高计皂 王伟 伍小驹 何驰剑 佘喜春 于 2021-09-14 设计创作，主要内容包括：本发明公开了一种二元醇的合成方法,涉及化工合成技术领域。将摩尔比为(1～60)：(0～30)：(0.5～10):1的酮、醇、烯烃和双氧水通过装有催化剂的反应器,烯烃与双氧水等发生环氧化反应,生成的环氧化物原位进一步与水反应生成二元醇,的反应条件是温度50～179℃,反应器压力0.3～5.0MPa,液体空速0.1～70h～(-1)。本发明提供的方法工艺简单,双氧水转化率高,目标产物选择性好,且整个过程环境友好,利于工业化生产和应用。(The invention discloses a method for synthesizing dihydric alcohol, and relates to the technical field of chemical synthesis. The molar ratio is (1-60): (0-30): (0.5-10) passing the ketone, alcohol, olefin and hydrogen peroxide solution of 1 through a reactor filled with a catalyst to perform epoxidation reaction on the olefin and the hydrogen peroxide solution and the like, and further reacting the generated epoxide in situ with water to generate dihydric alcohol, wherein the reaction conditions are that the temperature is 50-179 ℃, the pressure of the reactor is 0.3-5.0 MPa, and the liquid airspeed is 0.1-70 h ‑1 . The method provided by the invention has the advantages of simple process, high hydrogen peroxide conversion rate, good target product selectivity and environment-friendly whole process, and is beneficial to industrial production and application.)

1. A process for synthesizing diol from ketone, alcohol, olefin and dioxygenThe molar ratio of water is (1-60): (0-30): (0.5-10) passing the mixture in a reactor filled with a catalyst according to the proportion of 1, carrying out epoxidation reaction on olefin and hydrogen peroxide, further reacting the generated epoxide with water to generate dihydric alcohol, wherein the reaction conditions are as follows: the temperature is 50-179 ℃, the pressure of the reactor is 0.3-5.0 MPa, and the liquid space velocity is 0.1-70 h^-1The catalyst is a titanium-silicon molecular sieve, a modified titanium-silicon molecular sieve or a molded catalyst containing a titanium-silicon molecular sieve and a modified titanium-silicon molecular sieve.

2. The method for synthesizing glycol according to claim 1, wherein: the titanium silicalite molecular sieve is a titanium silicalite molecular sieve with an MFI structure, an MEL structure or an MFI/MEL intermediate structure.

3. The method for synthesizing the diol according to claim 1 or 2, wherein: the catalyst is selected from titanium silicalite molecular sieves having the general formula: xTiO₂·(1-x)SiO₂Wherein x is between 0.001 and 0.04.

4. The method for synthesizing glycol according to claim 1, wherein: the catalyst is in the shape of powder, small pieces, microspheres, spheres, extrudates and the like.

5. The method for synthesizing glycol according to claim 1, wherein: the hydrogen peroxide is H with the mass concentration less than or equal to 70 percent₂O₂An aqueous solution.

6. The method for synthesizing glycol according to claim 1, wherein: the ketone is acetone or butanone.

7. The method for synthesizing glycol according to claim 1, wherein: the alcohol is one of methanol, ethanol and propanol.

8. The method for synthesizing the diol according to any one of claims 1, 6, 7 and 8, wherein: the molar ratio of ketone to alcohol is equal to or greater than 1, preferably equal to or greater than 3, most preferably equal to or greater than 9.

9. The method for synthesizing glycol according to claim 1, wherein: the olefin is one or more of propylene, 1-butene, 2-butene, isobutene and butene in mixed C4.

10. The method for synthesizing glycol according to claim 1, wherein: the reactor is one of a fixed bed reactor, a slurry bed reactor, a pipeline reactor, a kettle type reactor and a fluidized bed reactor.

Technical Field

The invention relates to a method for synthesizing dihydric alcohol, in particular to a method for synthesizing C3-C4 dihydric alcohol by olefin in one step.

Background

Dihydric alcohols having the formula of C3-C4, such as 1, 2-propanediol, 1, 2-butanediol, 2, 3-butanediol, 2-methyl-1, 2-propanediol, are important chemical raw materials, and are mainly used for synthesizing polyester resins, antifreeze, cosmetics, photographic materials, lubricants, medical intermediates, various fine chemicals and the like.

In the prior art, 1, 2-propanediol, 1, 2-butanediol and 2-methyl-1, 2-propanediol are mainly produced by the corresponding epoxide reconversion, which is considered as a nucleophilic substitution reaction, whereby the opening of the alkylene oxide occurs, water acts as a nucleophile, usually at 180 ℃ and 220 ℃ and 15-25Bar, and in order to increase the selectivity of the target product, a large amount of water must be used simultaneously to suppress the production of polydihydric alcohol, usually 10-25 times as much water is used. However, even with a very large excess of water, the selectivity to the target product is low. However, this method has a significant disadvantage: that is, after the completion of the hydration reaction, a plurality of evaporators are installed in the apparatus for concentrating, dehydrating and fractionating the reaction mixture, resulting in a long production process flow, high energy consumption and the like, which is an uneconomical production method.

In the prior art, the production of 2, 3-butanediol is mainly based on biological methods. The method comprises the steps of generally adopting a common method to culture serratia marcescens, then inoculating strain seed liquid into a culture medium, introducing air, stirring, and fermenting and culturing for 3-6 hours at a certain temperature; then supplementing a product promoting factor-sodium acetate, and fermenting and culturing in the culture solution again for 3-6 hours at 25-35 ℃; and then controlling the respiratory entropy, and carrying out fermentation culture in the culture solution at the temperature of 25-35 ℃ for 32-36 hours to obtain the fermentation liquor of the 2, 3-butanediol. But the biological method has the defects of long fermentation period, complex process, low yield, high cost, low selectivity and the like, and the synthesis, popularization and application of the 2, 3-butanediol are severely restricted.

CN1850755A discloses a method for preparing diol, which is a method for preparing olefin carbonate from epoxide and carbon dioxide under the action of a catalyst, and the olefin carbonate reacts with water to generate corresponding diol and carbon dioxide. The method adopts olefin epoxide as raw material to synthesize dihydric alcohol, needs to adopt commercially available epoxide or to finish the synthesis of epoxide at upstream, and adopts two-step synthesis process, thus having long preparation flow.

CN1678598A discloses a continuous preparation method of propylene glycol, comprising three steps: the method comprises the steps of reacting propylene with hydrogen peroxide to obtain propylene oxide and propylene glycol, reacting the propylene oxide with water to obtain the propylene glycol, and separating to obtain the propylene glycol. The method also needs to synthesize a target product by a two-step synthesis process, namely two reaction systems, and the synthesis process is complex and has high investment; moreover, the patent mentions that most of the target products are generated by the second reactor at a higher temperature of 180-220 ℃ together with a stoichiometric excess of water, which inevitably results in a decrease in propylene glycol selectivity, and furthermore, on the one hand, the crude propylene oxide is obtained by separating and purifying the reaction product in the first step, which additionally increases the separation facilities and energy consumption, and on the other hand, the method does not solve the defects that in the conventional process, a large amount of water must be used to suppress the generation of polydiols, and a large amount of energy is consumed to remove water after the hydration reaction.

CN103193596A discloses a method for synthesizing 2, 3-butanediol, which is to react alcohol, mixed C4 hydrocarbon and hydrogen peroxide to generate 2, 3-butanediol. Although the method realizes the one-step synthesis of the 2, 3-butanediol, the patent mentions that a large amount of active alcohol is adopted as a solvent in the synthesis process, side reaction is easy to generate butanediol ether, and the product selectivity is seriously influenced, actually, the main product of the reaction is the butanediol ether, the 2, 3-butanediol is a coproduct, the 2, 3-butanediol selectivity is less than 50 percent in the system, and the selectivity of a target product is lower.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and invents a method for synthesizing C3-C4 dihydric alcohol by olefin in one step, which has the advantages of simple process, high product selectivity and environmental protection.

The purpose of the invention is realized by the following technical scheme: a synthesis method of dihydric alcohol comprises the following steps of: (0-30): (0.5-10) passing the mixture in a reactor filled with a catalyst in a ratio of 1, carrying out epoxidation reaction on olefin, hydrogen peroxide and the like, further reacting the generated epoxide with water to generate dihydric alcohol, wherein the reaction conditions are as follows: the temperature is 50-179 ℃, the pressure of the reactor is 0.3-5.0 MPa, and the liquid space velocity is 0.1-70 h^-1The catalyst is titanium-silicon molecular sieve, modified titanium-silicon molecular sieve or titanium-silicon-containing molecular sieve or modified titanium-silicon molecular sieveA catalyst of the type (I) is provided.

The titanium silicalite molecular sieve is a titanium silicalite molecular sieve with an MFI structure, an MEL structure or an MFI/MEL intermediate structure.

The catalyst is selected from titanium silicalite molecular sieves having the general formula: xTiO₂·(1-x)SiO₂Wherein x is between 0.001 and 0.04.

The catalyst is in the shape of powder, small pieces, microspheres, spheres, extrudates and the like.

The hydrogen peroxide is H with the mass concentration less than or equal to 70 percent₂O₂An aqueous solution.

The ketone is acetone or butanone, preferably acetone.

The alcohol is one of methanol, ethanol and propanol.

The molar ratio of the ketone to the alcohol is not less than 1, preferably not less than 3, more preferably not less than 9.

The olefin is one or more of propylene, 1-butene, 2-butene, isobutene and butene in mixed C4.

The reactor can be one of a fixed bed reactor, a slurry bed reactor, a pipeline reactor, a kettle type reactor and a fluidized bed reactor.

The invention has the following characteristics: the method for synthesizing the dihydric alcohol C3-C4 by adopting the olefin in one step adopts the inert solvent and a small amount of polar solvent to replace the polar solvent in the synthesis, thereby not only maintaining the epoxidation activity of the olefin, but also reducing the probability of side reaction between the polar solvent and an epoxidation product and greatly improving the selectivity of the dihydric alcohol; simultaneously, the corresponding dihydric alcohol prepared by olefin epoxidation and epoxide hydration is coupled to a reactor, thereby simplifying the process flow, reducing the investment and the operating cost, optimizing the synthesis process condition and improving the selectivity of the target product; the method is a green synthesis process, has no special production equipment requirement, is simple and easy to control in process, and is beneficial to industrial production and application.

The invention has the following beneficial effects: olefin is adopted to synthesize the dihydric alcohol C3-C4 in one step, the process flow is simple, and the investment and operation cost is low; the inert solvent and a small amount of polar solvent are selected to replace the polar solvent, so that the selectivity of the dihydric alcohol is high, and the technical economy is strong.

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

Example 1

10g of titanium silicalite molecular sieve catalyst is diluted by 10g of quartz sand and then is loaded in a fixed bed reactor. The mol ratio of acetone, methanol and hydrogen peroxide is 60: 15: 1, the mass concentration of hydrogen peroxide is 60%, the mol ratio of propylene and hydrogen peroxide is 1: 1, the acetone, the methanol and the hydrogen peroxide are respectively injected into a reactor by a metering pump, the propylene enters the reactor through a gas mass flow meter, and the feeding is in contact reaction with a titanium-silicon molecular sieve catalyst to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 179 ℃, the reaction pressure is 5.0MPa, and the liquid space velocity of the reaction bed is 70h^-1. The obtained product is analyzed by chromatography, the selectivity of the propylene glycol is 89.6 percent, and the conversion rate of the hydrogen peroxide is 99.5 percent.

Example 2

Taking 25% of A1₂O₃And mixing the titanium silicalite molecular sieve catalyst and 75% of the titanium silicalite molecular sieve catalyst uniformly, extruding the mixture to form strips, drying the strips at 100 ℃ for 4 hours, and roasting the strips at 540 ℃ for 4 hours to obtain the alumina modified titanium silicalite molecular sieve forming catalyst.

The prepared catalyst was diluted with 10g of quartz sand and charged in a fixed bed reactor. The mol ratio of acetone, methanol and hydrogen peroxide is 20: 5: 1, the mass concentration of the hydrogen peroxide is 60%, and the mol ratio of isobutene to the hydrogen peroxide is 10:1, respectively injecting acetone, methanol and hydrogen peroxide into a reactor by using a metering pump, injecting isobutene into the reactor by using the metering pump, and carrying out contact reaction on the fed materials and a formed catalyst containing a titanium-silicon molecular sieve to synthesize the 2-methyl-1, 2-propylene glycol. Reaction conditions are as follows: the reaction temperature is 50 ℃, the reaction pressure is 2MPa, and the liquid space velocity of the reaction bed is 3h^-1. The obtained product is analyzed by chromatography, the selectivity of the 2-methyl-1, 2-propanediol is 93.9 percent, and the conversion rate of the hydrogen peroxide is 90.3 percent.

Example 3

100g of titanium silicalite molecular sieve is filled in a slurry bed reactor, and the total volume of liquid is 2 litersCatalyst loading was 5% of total liquid. The mol ratio of butanone, ethanol and hydrogen peroxide is 60: 30: 1, the mass concentration of hydrogen peroxide is 70%, the mol ratio of 1-butene and hydrogen peroxide is 0.5: 1, butanone, ethanol and hydrogen peroxide are respectively injected into a reactor by a metering pump, 1-butene is injected into the reactor by the metering pump, and feeding is in contact reaction with a molding catalyst containing a titanium-silicon molecular sieve to synthesize 1, 2-butanediol. Reaction conditions are as follows: the reaction temperature is 100 ℃, the reaction pressure is 3MPa, and the liquid space velocity of the reaction bed layer is 0.1h^-1. The obtained product is analyzed, the selectivity of the 1, 2-butanediol is 95.1 percent, and the conversion rate of the hydrogen peroxide is 98.2 percent.

Example 4

The titanium silicalite molecular sieve is arranged in a kettle type batch reactor, the total volume of liquid is 3 liters, and the filling amount of the catalyst accounts for 5 percent of the total liquid. The mol ratio of acetone, propanol and hydrogen peroxide is 1: 1, the mass concentration of the hydrogen peroxide is 60%, the mol ratio of olefin and the hydrogen peroxide in the mixed C4 hydrocarbon is 10:1, the acetone, the propanol and the hydrogen peroxide are added at the beginning of the reaction, the mixed C4 hydrocarbon is injected into a reactor through a metering pump, and the materials are added and then are stabilized at constant temperature for 1 hour under the condition of stirring. Reaction conditions are as follows: the reaction temperature is 60 ℃, the reaction pressure is 0.3MPa, and the methanol is used. The selectivity of the obtained product is 92.1 percent and the conversion rate of the hydrogen peroxide is 89.0 percent through analysis.

Example 5

20g of titanium silicalite was charged to a fluidized bed reactor. The molar ratio of acetone to hydrogen peroxide is 10:1, the mass concentration of hydrogen peroxide is 60%, the molar ratio of 2-butylene to hydrogen peroxide is 2:1, the acetone and the hydrogen peroxide are mixed and then injected into a reactor through a metering pump, the 2-butylene is injected into the reactor through the metering pump, and the materials are in contact reaction with a catalyst to synthesize the 2, 3-butanediol. Reaction conditions are as follows: the reaction temperature is 130 ℃, the reaction pressure is 1.0MPa, and the liquid space velocity of the reaction bed layer is 2.3h^-1. The obtained product is analyzed, the selectivity of the 2, 3-butanediol is 94.6 percent, and the conversion rate of the hydrogen peroxide is 99.1 percent.

Example 6

20g of titanium silicalite was charged to a tubular reactor. The mol ratio of the acetone to the methanol to the hydrogen peroxide is 8: 1, the mass concentration of the hydrogen peroxide is 60 percent, and the butene in the butene-containing mixed C4The mol ratio of the hydrogen peroxide is 3:1, acetone, methanol and the hydrogen peroxide are mixed and then injected into a reactor through a national metering pump, the mixed C4 containing butylene is injected into the reactor through the metering pump, and the materials and a catalyst are in contact reaction to synthesize the butanediol. Reaction conditions are as follows: the reaction temperature is 90 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 0.8h^-1. The selectivity of the obtained product is 94.9 percent and the conversion rate of the hydrogen peroxide is 98.1 percent through analysis.

Example 7

10g of the shaped titanium silicalite catalyst was loaded in a fixed bed reactor and the catalyst preparation was as in example 2. The mol ratio of acetone, methanol and hydrogen peroxide is 8: 2:1, the mass concentration of hydrogen peroxide is 50%, the mol ratio of propylene and hydrogen peroxide is 2:1, the acetone, the methanol and the hydrogen peroxide are mixed and then injected into a reactor through a metering pump, the propylene is injected into the reactor through the metering pump, and the materials and a catalyst are in contact reaction to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 110 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 2.0h^-1. The obtained product is analyzed, the selectivity of the propylene glycol is 93.8 percent, and the conversion rate of the hydrogen peroxide is 98.7 percent.

Example 8

10g of the shaped titanium silicalite catalyst was loaded in a fixed bed reactor and the catalyst preparation was as in example 2. The mol ratio of acetone, methanol and hydrogen peroxide is 8: 1, the mass concentration of hydrogen peroxide is 50%, the mol ratio of propylene and hydrogen peroxide is 2:1, the acetone, the methanol and the hydrogen peroxide are mixed and then injected into a reactor through a metering pump, the propylene is injected into the reactor through the metering pump, and the materials are in contact reaction with a catalyst to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 110 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 2.0h^-1. The obtained product is analyzed, the selectivity of the propylene glycol is 94.3 percent, and the conversion rate of the hydrogen peroxide is 98.1 percent.

Example 9

10g of the shaped titanium silicalite catalyst was loaded in a fixed bed reactor and the catalyst preparation was as in example 2. The mol ratio of the acetone, the methanol and the hydrogen peroxide is 8: 0.5: 1, the mass concentration of the hydrogen peroxide is 50 percent, the mol ratio of the propylene and the hydrogen peroxide is 2:1, and the acetone and the methanol areAnd mixing alcohol and hydrogen peroxide, injecting the mixture into a reactor through a metering pump, injecting propylene into the reactor through the metering pump, and carrying out contact reaction on the materials and a catalyst to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 110 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 2.0h^-1. The obtained product is analyzed, the selectivity of the propylene glycol is 95.1 percent, and the conversion rate of the hydrogen peroxide is 97.5 percent.

Example 10

10g of the shaped titanium silicalite catalyst was loaded in a fixed bed reactor and the catalyst preparation was as in example 2. The mol ratio of acetone, methanol and hydrogen peroxide is 8: 1, no methanol is added, the mass concentration of hydrogen peroxide is 50%, the mol ratio of propylene and hydrogen peroxide is 2:1, the acetone and the hydrogen peroxide are mixed and then injected into a reactor through a metering pump, the propylene is injected into the reactor through the metering pump, and the materials are in contact reaction with a catalyst to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 110 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 2.0h^-1. The obtained product is analyzed, the selectivity of the propylene glycol is 98.5 percent, and the conversion rate of the hydrogen peroxide is 93.8 percent.

Comparative example 1

10g of the shaped titanium silicalite catalyst was loaded in a fixed bed reactor and the catalyst preparation was as in example 2. The mol ratio of the methanol to the hydrogen peroxide is 8: 1, no acetone is added, the mass concentration of the hydrogen peroxide is 50%, the mol ratio of the propylene to the hydrogen peroxide is 2:1, the methanol and the hydrogen peroxide are mixed and then injected into a reactor through a metering pump, the propylene is injected into the reactor through the metering pump, and the materials and the catalyst are in contact reaction to synthesize the propylene glycol. Reaction conditions are as follows: the reaction temperature is 110 ℃, the reaction pressure is 2.0MPa, and the liquid space velocity of the reaction bed layer is 2.0h^-1. The obtained product is analyzed, the selectivity of the propylene glycol is 18.6 percent, and the conversion rate of the hydrogen peroxide is 99.3 percent.

From the results of examples 1 to 10 and comparative example 1, it can be seen that the method of the present invention for synthesizing glycol can achieve both glycol selectivity and hydrogen peroxide conversion, and obtain higher glycol yield.