WO2016184038A1

WO2016184038A1 - Method for preparing cyclohexene oxide using micro-flow field reaction technology

Info

Publication number: WO2016184038A1
Application number: PCT/CN2015/093162
Authority: WO
Inventors: 郭凯; 方正; 何伟; 李昕; 张锴; 万力; 欧阳平凯
Original assignee: 南京工业大学
Priority date: 2015-05-15
Filing date: 2015-10-29
Publication date: 2016-11-24
Also published as: CN104817520B; CN104817520A

Abstract

Disclosed is a method for preparing cyclohexene oxide using a micro-flow field reaction technology. The method is a method for preparing cyclohexene oxide from raw materials such as m-chlorobenzoyl chloride, an aqueous hydrogen peroxide solution and inorganic base in a micro-channel modular reaction device. Compared with the prior art, the method of the present invention is simple and easy to control, adopts easily available and cheap raw materials, is high in yield and conversion rate, and facilitates industrial production.

Description

Method for preparing epoxy cyclohexane by micro flow field reaction technology

Technical field

The invention belongs to the field of chemical synthesis, and particularly relates to a method for preparing epoxy cyclohexane by using a microfluidic field reaction technique.

Background technique

Epoxycyclohexane is a versatile organic intermediate that has been used in surfactants, epoxies, paints, adhesives, pharmaceuticals, pesticides, and polymeric materials. Due to the presence of an active epoxy group in the molecular structure of epoxycyclohexane, the epoxy group is susceptible to ring-opening reaction under acid or base catalysis, and reacts with ammonia, amine, alcohol, phenol, carboxylic acid, water and the like. Produce high value-added compounds.

At present, the preparation methods of epoxycyclohexane mainly include: (1) organic peroxyacid method, but the process is usually used as an oxidizing agent such as peroxyformic acid or acetic acid, the peroxyacid is unstable, easy to be decomposed, difficult to store, and the reaction time is difficult to control. . (2) Cyclohexene is added to HOCl and then condensed into a ring method. This process requires strong acid catalysis, and a large amount of 1,2-cyclohexanediol is often formed in the reaction, which affects the yield. (3) Hydrogen peroxide oxidation method. Although there are many advantages, due to instability and easy decomposition characteristics, it can only be used to catalyze the oxidation of molecules with a small molecular weight at a low temperature, and requires a highly active catalyst. (4) Alkyl hydroperoxide method. The method uses the alkyl hydrogen peroxide containing no a-H as an oxidant, and has the characteristics of mild reaction, convenient control, high yield and good catalytic selectivity. (5) Molecular oxygen oxidation method. The law is still under study and has certain development prospects. However, in the report, the epoxidized product is usually a mixture of epoxycyclohexane, cyclohexenol and cyclohexenone, and the yield is low and the separation is complicated. In addition, there are electrochemical epoxidation methods, biological methods, and the like. Epoxycyclohexane is chemically active and highly hydrolyzable. Therefore, the method of preparing cyclohexene by hydrogen peroxide to oxidize cyclohexane generally adds a large amount of organic solvents such as chloroform, dichloromethane, and 1,2-dichloroethane. Alkane or the like to slow the hydrolysis of epoxycyclohexane. The addition of a large amount of organic solvent will reduce the production capacity, increase the recovery cost of the solvent and increase the production cost of epoxycyclohexane. On the other hand, the use of toxic and harmful organic solvents greatly reduces the hydrogen peroxide as a green oxidant. Advantage. The Dalian Institute of Material Science and Technology of the Chinese Academy of Sciences applies the phase transfer technology to the preparation of epoxycyclohexane. This type of catalyst is insoluble in the reaction medium, but reacts with hydrogen peroxide to form an active substance dissolved in the reaction medium. When the hydrogen peroxide is consumed, the catalyst is analyzed. It came out, but in actual production, it was found that such a catalyst is difficult to maintain stable catalytic performance, and the production cost is high, and it is difficult to industrially produce.

CN101348472A discloses a titanium-modified silica as a catalyst, cyclohexene and an organic peroxide. As a method for preparing epoxycyclohexane as a substrate, the method can solve the problems of environmental pollution and corrosion of equipment, but the preparation of the catalyst is complicated, the organic peroxide is expensive, and it cannot be industrialized on a large scale. CN101691363A discloses a method for preparing epoxycyclohexane by using a titanium-titanium molecular sieve as a catalyst and adding a basic auxiliary agent, but such a catalyst has a small particle size, and difficulty in recovery results in difficulty in industrial application. Zhengzhou University CN101020669A prepares epoxycyclohexane with organic resin compound and quaternary ammonium phosphotungstate as catalyst and hydrogen peroxide as oxidant. The catalyst has high catalytic activity, high reaction selectivity and easy recovery. However, the catalyst preparation process is complicated and the cost is too high, which is not suitable for industrial applications. CN1542007A uses cyclohexene as raw material, molecular oxygen as oxidant, n-pentanal or isovaleraldehyde or isobutyraldehyde as an intermediary, and at least one of manganese or iron or cobalt or nickel oxide, at least molybdenum or tungsten One of the oxides, at least one of nitrogen or phosphorus or arsenic oxyacids, is reacted at a temperature of 30 to 80 ° C for 2 to 12 hours to prepare epoxycyclohexane. The compound catalyst used in the method can oxidize an aldehyde to a peroxyacid and further epoxidize cyclohexene to obtain an epoxycyclohexane. The method has high catalyst preparation cost and low single-pass conversion rate of raw materials.

The domestic large-scale production manufacturers include Shandong Gaomi Yinying Chemical Fiber Co., Ltd. (referred to as Gaomi Yinying), Hunan Yueyang Changde Chemical Industry Co., Ltd. (referred to as Yueyang Changde) and Yueyang Petrochemical General Factory Longxing Industrial Company (referred to as Longxing Industrial). . However, these manufacturers adopt batch operation, the output is small, the equipment self-control level is low, and the production cannot be continuous, and the required catalyst preparation is complicated, the reusability is poor, and the production cost is high.

Summary of the invention

The technical problem to be solved by the present invention is to provide a method for preparing epoxy cyclohexane by using a microfluidic field reaction technology, so as to solve the problem that the reaction existing in the preparation of epoxycyclohexane in the prior art is difficult to control, the cost is too high, and the efficiency is high. Low problem.

In order to solve the above problems, the technical solution adopted by the present invention is as follows:

A method for preparing epoxycyclohexane by using a microfluidic reaction technique, which comprises the following steps:

(1) mixing m-chlorobenzoyl chloride, aqueous hydrogen peroxide solution and inorganic base, and then injecting into the first microstructure reactor of the microchannel modular reaction device, reacting at 0 to 60 ° C, and the residence time is 0.5 to 5 min;

(2) mixing the mixed system obtained in the step (1) with an acidic dichloromethane solution, and then injecting into the oil-water separation device of the microchannel modular reaction device, and injecting the second microstructure reaction into the organic layer and cyclohexene via the micromixer. After the reaction, the reaction is carried out at 10 to 60 ° C, and the residence time is 5 to 20 minutes;

(3) introducing the mixed system obtained in the step (2) into a product collecting device in the microchannel modular reaction device, sequentially washing the organic phase with a sodium carbonate aqueous solution and water to pH 7.0, and drying to obtain an epoxy ring. alkyl;

Wherein the microchannel modular reaction device comprises a first microstructure mixer connected in series by a pipeline, a first microstructure reactor, a second microstructure mixer, a water-water separation device third microstructure mixer, a second microstructure reactor, and a product collection device; wherein, the first raw material storage tank and the second raw material storage tank a feed port of the microstructure mixer is connected, a third material storage tank is connected to the feed port of the second microstructure mixer, and a fourth material storage tank is connected to the feed port of the third microstructure mixer;

Wherein, the m-chlorobenzoyl chloride is located in the first raw material storage tank, the aqueous hydrogen peroxide solution and the inorganic alkali are located in the second raw material storage tank, the acidic dichloromethane solution is located in the third raw material storage tank, and the cyclohexene is located in the fourth raw material storage tank.

among them,

The microstructure mixer is a slit plate mixer LH25 (Hastelloy C), a valve-assisted mixer (Hastelloy C); purchased from Ehrfeld Mikrotechnik BTS GmbH, model numbers 0109-4-0004-F; 0111-2-0014- F;

The microstructure reactor is meaner reactor HC, sandwich reactor HC, fixed bed meander reactor HC, Hastelloy capillary; preferably sandwich reactor HC, available from Ehrfeld Mikrotechnik BTS GmbH, model number 0211-2-0314-F; 1-0004-F; 0222-2-2004-F.

In the step (1), the concentration of the solute hydrogen peroxide in the aqueous hydrogen peroxide solution is 30% by weight.

In the step (1), the inorganic base is potassium hydroxide, sodium hydroxide or barium hydroxide.

In the step (1), the molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is from 1:1 to 10, preferably from 1:4 to 8.

In the step (1), the molar ratio of the hydrogen peroxide to the inorganic base is 1:1 to 5, preferably 1:1 to 4.

In the step (1), the reaction temperature is preferably 10 to 40 ° C, and the reaction time is preferably 0.5 to 3 min;

Wherein, in the step (2), the reaction temperature is preferably 20 to 40 ° C, and the reaction time is preferably 10 to 20 min;

In the step (2), the acidic dichloromethane solution is prepared by mixing 1 mol/L hydrochloric acid aqueous solution with dichloromethane and stirring for 2 hours, and then removing the aqueous layer to obtain an acidic dichloromethane solution.

In the step (2), the pH of the acidic dichloromethane solution is 2 to 3.

In the step (2), the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is 1:1 to 8, preferably 1:1 to 6.

In the step (3), the concentration of the solute sodium carbonate in the sodium carbonate aqueous solution is 5% by weight.

Advantageous Effects: Compared with the prior art, the method of the invention has the advantages of simple and easy control, low cost of raw materials, high yield and high conversion rate, and is advantageous for industrial production.

DRAWINGS

Figure 1 is a schematic diagram of the reaction scheme of the present invention.

detailed description

The invention can be better understood in light of the following examples. However, those skilled in the art will understand that the description of the embodiments is only intended to illustrate the invention and should not be construed as limiting the invention as described in the claims.

The reaction feedstock is passed through a precision and low pulsation pump (such as an HPLC pump or syringe pump) into the micromixer and subsequent equipment, enabling the material to continuously control its residence time through the microchannel modular reaction unit. The second microstructured reactor and the product collection bottle are connected by a length of polytetrafluorocapillary capillary which can be immersed in an ice water bath to terminate the reaction.

The microstructure mixer is a slit plate mixer LH25 (Hastelloy C), a valve-assisted mixer (Hastelloy C); purchased from Ehrfeld Mikrotechnik BTS GmbH, model numbers 0109-4-0004-F; 0111-2-0014- F.

The microstructure heat exchanger was a coaxial heat exchanger (Hastelloy C); available from Ehrfeld Mikrotechnik BTS GmbH under the model number 0309-3-0314-F.

Example 1:

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and sodium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:4, hydrogen peroxide and hydrogen. The molar ratio of sodium oxide is 1:1, and it stays at 10 ° C for 0.5 min; the first microstructure reactor discharge is mixed with the acidic dichloromethane solution and injected into the oil-water separation device, the lower dichloromethane solution and cyclohexene. After mixing, the micro-mixer and the second microstructure reactor are respectively controlled, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to be 1:1, and the mixture is kept at 20 ° C for 10 min, and the second microstructure reactor is discharged. The material was introduced into a separator, and the organic phase was washed with a 5 wt% sodium carbonate solution and distilled water, respectively, to pH = 7.0, and dried to obtain epoxycyclohexane. The conversion ratio of the cyclohexene raw material was 90%.

Example 2:

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and sodium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:8, hydrogen peroxide and hydrogen. The molar ratio of sodium oxide is 1:4, and the temperature stays at 40 ° C for 3 min; the first microstructure reactor discharge is mixed with the acidic dichloromethane solution and injected into the oil-water separation device, and the lower dichloromethane solution is mixed with cyclohexene. After that, the micro-mixer and the second microstructure reactor are successively controlled, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to 1:6, and the temperature is kept at 40 ° C for 20 min, and the second microstructure reactor is discharged. The mixture was introduced into a separator, and the organic phase was washed with a 5 wt% sodium carbonate solution and distilled water to pH = 7.0, respectively, and dried to obtain epoxycyclohexane. The conversion ratio of the cyclohexene raw material was 98%.

Example 3:

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and sodium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:6, hydrogen peroxide and hydrogen. The molar ratio of sodium oxide is 1:2, and the mixture is kept at 30 ° C for 2 min; the first microstructure reactor discharge is mixed with the acidic dichloromethane solution and injected into the oil-water separation device, and the lower dichloromethane solution is mixed with cyclohexene. After that, the micro-mixer and the second microstructure reactor are respectively controlled, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to 1:4, and the mixture is kept at 30 ° C for 15 min, and the second microstructure reactor is discharged. The mixture was introduced into a separator, and the organic phase was washed with a 5 wt% sodium carbonate solution and distilled water, respectively, to pH = 7.0, and dried to obtain epoxycyclohexane. The conversion ratio of the cyclohexene raw material was 95%.

Example 4:

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and potassium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:6, hydrogen peroxide and hydrogen. The molar ratio of sodium oxide is 1:2, and the mixture is kept at 30 ° C for 2 min; the first microstructure reactor discharge is mixed with the acidic dichloromethane solution and injected into the oil-water separation device, and the lower dichloromethane solution is mixed with cyclohexene. After that, the micro-mixer and the second microstructure reactor are respectively controlled, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to 1:4, and the mixture is kept at 30 ° C for 15 min, and the second microstructure reactor is discharged. The mixture was introduced into a separator, and the organic phase was washed with a 5 wt% sodium carbonate solution and distilled water to pH = 7.0, respectively, and dried to obtain epoxycyclohexane. The conversion ratio of the cyclohexene raw material was 94.5%.

Example 5:

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and cesium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:6, hydrogen peroxide and hydrogen. Sodium oxide molar ratio 1:2, stay at 30 ° C for 2 min; the first microstructure reactor discharge and acidic dichloromethane solution mixed into the oil-water separation device, the lower layer of dichloromethane solution and cyclohexene mixed and then passed through the micro a mixer, a second microstructure reactor, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to 1:4, and the mixture is stopped at 30 ° C for 15 minutes, and the second microstructure reactor discharge is introduced into the separator. The organic phase was washed with a 5 wt% sodium carbonate solution and distilled water to pH = 7.0, respectively, and dried to obtain epoxycyclohexane. The conversion of the cyclohexene raw material was 92.5%.

Example 6

A mixture of m-chlorobenzoyl chloride, hydrogen peroxide and sodium hydroxide is injected into the first microstructure reactor of the microchannel modular reaction unit. The molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:2, hydrogen peroxide and hydrogen. The molar ratio of sodium oxide is 1:1, and the mixture is kept at 0 ° C for 5 min; the first microstructure reactor discharge is mixed with the acidic dichloromethane solution and injected into the oil-water separation device, and the lower dichloromethane solution is mixed with cyclohexene. After that, the micro-mixer and the second microstructure reactor are respectively controlled, wherein the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is controlled to 1:8, and the mixture is kept at 10 ° C for 20 min, and the second microstructure reactor is discharged. The mixture was introduced into a separator, and the organic phase was washed with a 5 wt% sodium carbonate solution and distilled water to pH = 7.0, respectively, and dried to obtain epoxycyclohexane. The conversion ratio of the cyclohexene raw material was 91%.

Claims

A method for preparing epoxycyclohexane by using a microfluidic reaction technique, comprising the steps of:

(1) mixing m-chlorobenzoyl chloride, aqueous hydrogen peroxide solution and inorganic base, and then injecting into the first microstructure reactor of the microchannel modular reaction device, reacting at 0 to 60 ° C, and the residence time is 0.5 to 5 min;

(2) mixing the mixed system obtained in the step (1) with an acidic dichloromethane solution, and then injecting into the oil-water separator of the microchannel modular reaction device, mixing the organic layer and the cyclohexene, and injecting the third micromixer. After the two microstructured reactor, the reaction is carried out at 10 to 60 ° C, and the residence time is 5 to 20 minutes;

(3) introducing the mixed system obtained in the step (2) into a product collector in the microchannel modular reaction device, sequentially washing the organic phase with a sodium carbonate aqueous solution and water to pH 7.0, and drying to obtain an epoxy ring. alkyl;

Wherein the microchannel modular reaction device comprises a first microstructure mixer, a first microstructure reactor, a second microstructure mixer, a water separator, a third microstructure mixer, and the like, which are sequentially connected by a pipeline. a second microstructure reactor and a product collector; wherein the first raw material storage tank and the second raw material storage tank are connected to the feed port of the first microstructured mixer, and the third raw material storage tank and the second microstructured mixer are advanced The feed port is connected, and the fourth raw material storage tank is connected to the feed port of the third microstructured mixer.
The production method according to claim 1, wherein in the step (1), the concentration of the solute hydrogen peroxide in the aqueous hydrogen peroxide solution is 30% by weight.
The preparation method according to claim 1, wherein in the step (1), the inorganic base is potassium hydroxide, sodium hydroxide or barium hydroxide.
The preparation method according to claim 1, wherein in the step (1), the molar ratio of m-chlorobenzoyl chloride to hydrogen peroxide is 1:1 to 10.
The preparation method according to claim 1, wherein in the step (1), the molar ratio of the hydrogen peroxide to the inorganic base is 1:1 to 5.
The preparation method according to claim 1, wherein in the step (2), the acidic dichloromethane solution is prepared by mixing a 1 mol/L hydrochloric acid aqueous solution with dichloromethane and stirring for 2 hours, and then removing the water layer, that is, An acidic dichloromethane solution was obtained.
The preparation method according to claim 1, wherein in the step (2), the pH of the acidic dichloromethane solution is 2 to 3.
The preparation method according to claim 1, wherein in the step (2), the molar ratio of cyclohexene to m-chloroperoxybenzoic acid is 1:1 to 8.
The preparation method according to claim 1, wherein in the step (3), in the aqueous sodium carbonate solution, The concentration of the solute sodium carbonate was 5 wt%.