Ketone-alcohol dehydration condensation reaction device and method

Abstract

The present application discloses a ketone-alcohol dehydration condensation reaction device and method, the device includes a reaction unit, a gas phase treatment unit, and a liquid phase separation unit; the reaction unit includes a reactor with a cavity; the gas phase treatment unit includes a stripping tower and a decanter; the liquid phase separation unit includes a separator; along the gas phase flow direction, the reaction unit is connected to the gas phase treatment unit; along the liquid phase flow direction, the reaction unit is connected to the liquid phase separation unit. The device adopts the "reaction-distillation-decantation-separation" combined operation, which can improve the overall reaction yield of ketone-alcohol condensation and reduce the equipment specifications through continuous production, and belongs to the field of chemical technology. This method can be used for the continuous production of ketal compounds, thereby reducing equipment specifications, reducing raw material losses, and improving product yields.

Description

Technical Field

[0001] The present application relates to a ketone-alcohol dehydration condensation reaction device and method, belonging to the field of reaction technology. Background Art

[0002] Ketals are a type of fine chemical products with a special floral and fruity aroma, and are therefore widely used in the fragrance and flavoring of cosmetics, alcoholic beverages, food, and other daily necessities, as well as in the synthesis of spices. At the same time, ketal compounds are also often used as carbonyl protecting agents and drug intermediates due to their synthetic reversibility.

[0003] The existing ketal production process uses ketone alcohol as raw material to undergo dehydration condensation reaction, and adopts azeotropic evaporation method to evaporate water and water-carrying agent together to improve the raw material conversion rate. The whole process adopts intermittent operation, the equipment specifications are large, the energy consumption is high, and a lot of raw material alcohol is carried away in the wastewater, resulting in a waste of raw materials, reducing the overall yield of the product and limiting the scale of production. Therefore, it is necessary to improve the process of ketone alcohol condensation reaction, develop a continuous production method, improve the product yield, and reduce the equipment scale and investment. Summary of the invention

[0004] The present application provides a ketone-alcohol condensation reaction device, which can be operated continuously and improve the product yield.

[0005] According to one aspect of the present application, a ketone-alcohol dehydration condensation reaction device is provided.

[0006] The device comprises a reaction unit, a gas phase treatment unit, and a liquid phase separation unit;

[0007] The reaction unit comprises a reactor having a cavity;

[0008] The gas phase treatment unit includes a stripping tower, a condenser, a reflux device, and a decanter;

[0009] The liquid phase separation unit comprises a separator;

[0010] The reaction unit is connected to the gas phase treatment unit and the liquid phase separation unit respectively;

[0011] The gas phase outlet of the reactor is connected to the gas phase inlet of the stripping tower, the gas phase outlet of the stripping tower is connected to the inlet of the reflux device through a condenser, the liquid phase outlet of the reflux device is connected to the liquid phase inlet of the stripping tower and the liquid phase inlet of the decanter through pipeline I and pipeline II, respectively; the oil phase outlet of the decanter is connected to the oil phase inlet of the reactor.

[0012] Optionally, the decanter further comprises a water phase outlet;

[0013] The liquid phase outlet of the reflux device is connected to pipeline I and pipeline II respectively through pump I.

[0014] Optionally, a stirrer is provided in the cavity of the reactor;

[0015] A jacket is arranged outside the cavity of the reactor for heating the reactor.

[0016] Optionally, the liquid phase outlet of the reactor is connected to the liquid phase inlet of the separator, and the outlet I of the separator is connected to the inlet I of the reactor;

[0017] Preferably, the outlet I of the separator is connected to the inlet I of the reactor via a pump II;

[0018] The separator also includes a product outlet;

[0019] Optionally, the stripping tower is a plate tower;

[0020] The theoretical number of plates of the plate tower is 8 to 25; the number of plates theoretically affects the separation effect of by-product water. If the theoretical number of plates is too low, the water component cannot be separated to the greatest extent, and if the theoretical number of plates is too high, the equipment investment will be affected.

[0021] According to another aspect of the present application, a method for continuous synthesis of ketal is provided, wherein raw materials containing ketone, alcohol and water-containing agent are introduced into the reactor of the device to synthesize ketal.

[0022] The ketone is selected from at least one of cyclohexanone, cyclohexanedione, cyclopentanone and butanone;

[0023] The alcohol is a dihydroxy alcohol compound;

[0024] The dihydroxy alcohol compound is selected from at least one of ethylene glycol, propylene glycol, butylene glycol and hexylene glycol;

[0025] The water-carrying agent is selected from at least one of cyclohexane, benzene, dichloromethane, carbon tetrachloride and petroleum ether.

[0026] Optionally, the method comprises the following steps:

[0027] (1) adding raw materials from the raw material inlet of the reactor into a reactor containing a catalyst, wherein the raw materials are stirred and mixed by the stirrer in the reactor and heated to the reaction temperature by the jacket to react to generate gas phase products and liquid phase products;

[0028] (2) The gas phase product described in step (1) passes through the stripping tower and is exchanged with the liquid phase refluxed through the reflux device through mass transfer, and the gas phase containing water and water agent is separated from the acetal product; the gas phase containing water and water agent flows through a condenser to condense into a liquid phase, passes through the reflux device, pipeline I, pipeline II, returns to the stripping tower, and is sent to a decanter; the liquid phase entering the decanter is separated into an oil phase and a water phase, the oil phase returns to the reactor, and the water phase is discharged as waste water;

[0029] The liquid product described in step (1) enters the separator, and is separated by gravity sedimentation to obtain slurry and reaction products. The slurry is returned to the reactor, and the reaction product is discharged from the product outlet of the separator.

[0030] Optionally, in step (1), the reaction temperature is 90-150°C.

[0031] Preferably, the reaction temperature may be independently selected from 90°C, 100°C, 105°C, 110°C, 120°C, 130°C, 140°C, 150°C.

[0032] Optionally, in step (2), the pressure of the stripping tower is 101.3 to 110 kPaA;

[0033] Preferably, the pressure of the stripping tower is 101.3-105 kPaA;

[0034] The temperature of the stripping tower is 42-75°C;

[0035] Preferably, the temperature at the top of the stripping tower is 42-60°C;

[0036] The reflux ratio of the stripping tower is 0.1 to 30;

[0037] Preferably, the reflux ratio of the stripping tower is 0.1-10.

[0038] The oil phase includes a water carrier and a ketone.

[0039] The slurry includes the catalyst and unseparated products.

[0040] One solution of the device of the present invention comprises a reaction unit, a gas phase treatment unit, and a liquid phase separation unit;

[0041] The reaction unit comprises a reactor having a cavity, a stirrer is arranged in the cavity of the reactor, and a jacket is arranged outside the cavity of the reactor for heating the reactor;

[0042] The gas phase treatment unit comprises a stripping tower, a condenser, a reflux device, and a decanter; the stripping tower is a plate tower; the number of theoretical plates of the plate tower is 8 to 25;

[0043] The liquid phase separation unit comprises a separator;

[0044] The reaction unit is connected to the gas phase treatment unit and the liquid phase separation unit respectively;

[0045] The gas phase outlet of the reactor is connected to the gas phase inlet of the stripping tower, the gas phase outlet of the stripping tower is connected to the inlet of the reflux device through a condenser, the liquid phase outlet of the reflux device is connected to pipeline I and pipeline II respectively through pump I, pipeline I and pipeline II are respectively connected to the liquid phase inlet of the stripping tower and the liquid phase inlet of the decanter; the oil phase outlet of the decanter is connected to the oil phase inlet of the reactor; the decanter also includes a water phase outlet.

[0046] The liquid phase outlet of the reactor is connected to the liquid phase inlet of the separator, and the outlet I of the separator is connected to the inlet I of the reactor via a pump II; the separator also includes a product outlet.

[0047] The beneficial effects of this application include:

[0048] 1) The device and method provided in this application can realize continuous production of ketal and reduce equipment specifications;

[0049] 2) The device and method provided in this application can achieve stable operation and ensure product quality;

[0050] 3) The device and method provided in the present application can recover the unreacted raw alcohol contained in the gas phase and recover it to the reactor through stripping in a stripping tower, thereby reducing the loss in the separation process and improving the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a schematic diagram of a ketone-alcohol condensation reaction device containing a stirrer in the present application.

[0052] Among them: 1. Reactor; 2. Stripping tower; 3. Condenser; 4. Reflux tank; 5. Circulation pump; 6. Decanter; 7. Separator; 8. Slurry pump; 9. Agitator; 10. Jacket. DETAILED DESCRIPTION

[0053] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0054] Unless otherwise specified, the raw materials and catalysts in the examples of this application were purchased through commercial channels.

[0055] Example 1

[0056] like Figure 1The present invention provides another scheme of a ketal dehydration condensation reaction device, comprising: a reactor 1, a stripping tower 2 (the number of plates in the tower is 25), a condenser 3, a reflux tank 4, a circulation pump 5, a decanter 6, a separator 7, and a slurry pump 8, wherein a stirrer 9 is provided in the cavity of the reactor 1, and a jacket 10 is provided outside the cavity, the gas phase outlet at the top of the reactor 1 is connected to the gas phase inlet at the bottom of the stripping tower 2, the gas phase outlet at the top of the stripping tower 2 is connected to the condenser 3, the reflux tank 4, and the inlet of the circulation pump 5 in sequence, the outlet pipeline of the circulation pump 5 is divided into two branches, which are respectively connected to the liquid phase inlet of the stripping tower 2 and the liquid phase inlet of the decanter 6, and the oil phase outlet of the decanter 6 is connected to the oil phase inlet of the reactor 1;

[0057] The liquid phase outlet of the reactor 1 is connected to the liquid phase inlet of the separator 7, the slurry outlet of the separator 7 is connected to the raw material inlet II of the reactor 1 through a slurry pump 8, and a product outlet is provided at the top of the separator 7.

[0058] Example 2

[0059] This embodiment also provides a method for continuous synthesis of ketal, using Figure 1 The device shown specifically comprises the following steps:

[0060] Cyclohexanone, ethylene glycol and cyclohexane with water are sent as reaction materials into a reactor 1 filled with a supported phosphomolybdic tungstic acid catalyst, and are heated to 105°C by steam in the jacket, undergoing a dehydration condensation reaction to generate cyclohexanone ethylene glycol acetal and a large amount of water. The water, cyclohexane and a small amount of mixed steam of reaction raw materials and products obtained after the reaction enter the stripping tower 2 through the connection point, and are exchanged with the reflux liquid flowing down from the top of the tower step by step by mass transfer. Finally, they flow out from the top of the stripping tower 2 and are condensed by the condenser 3 to obtain a condensate at 55°C, which is sent to the reflux tank 4 for short-term buffering. The reflux ratio of the stripping tower 2 is 0.26, the top pressure is 102kPaA, the number of theoretical plates is 15, and the top temperature is 55°C. After being pressurized by the circulating pump 5, part of the condensate returns to the top of the stripping tower 2 as reflux, and part of it is sent to the decanter 6 for stable stratification. The oil phase in the decanter 6 is cyclohexane with a molar fraction greater than 99.6%, which is returned to the reactor for use as a dehydrating agent. The water phase is wastewater with a molar fraction greater than 99.5%. The mixture at the bottom of the reactor 1 is sent to the separator 7 for separation. The catalyst and part of the product mixture at the bottom are pressurized by the slurry pump 8 and returned to the reactor 1. The upper product is sent out of the reaction device to the separation unit. The overall yield of the process product is 85%, which is higher than the single-pass yield of 82%, and can be used for continuous production of cyclohexanone ethylene glycol acetal.

[0061] Example 3

[0062] This embodiment also provides a method for continuous synthesis of ketal, using Figure 1 The device shown specifically comprises the following steps:

[0063] Butanone, ethylene glycol and cyclohexane with water are sent as reaction materials into a reactor 1 containing a copper-loaded SBA-15 catalyst, and are heated to 110°C by steam in the jacket, undergoing a dehydration condensation reaction to generate butanone glycol acetal and a large amount of water. The water, cyclohexane and a small amount of mixed steam of reaction raw materials and products obtained after the reaction enter the stripping tower 2 through the connection point, and are exchanged with the reflux liquid flowing down from the top of the tower step by step by mass transfer. Finally, they flow out from the top of the stripping tower 2 and are condensed by the condenser 3 to obtain a condensate at 57°C, which is sent to the reflux tank 4 for short-term buffering. The reflux ratio of the stripping tower 2 is 1.56, the top pressure is 102kPaA, the number of theoretical plates is 15, and the top temperature is 57°C. After being pressurized by the circulating pump 5, part of the condensate returns to the top of the stripping tower 2 as reflux, and part is sent to the decanter 6 for stable stratification. The oil phase in the decanter 6 is composed of cyclohexane with a molar fraction of 86% and butanone with a molar fraction of 13.5%, which is returned to the reactor as a dehydrating agent and circulating raw material. The aqueous phase is wastewater with a molar fraction greater than 98.9%. The mixture at the bottom of the reactor 1 is sent to the separator 7 for separation. The catalyst and part of the product mixture at the bottom are pressurized by the slurry pump 8 and returned to the reactor 1. The upper product is sent out of the reaction device to the separation unit. The overall yield of the process product is 96.6%, which is higher than the single-pass yield of 85%, and can be used for continuous butanone glycol acetal production.

[0064] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A ketal synthesis continuous reaction device, characterized in that: The device comprises a reaction unit, a gas phase treatment unit, and a liquid phase separation unit; The reaction unit comprises a reactor having a cavity; The gas phase treatment unit includes a stripping tower, a condenser, a reflux device, and a decanter; The liquid phase separation unit comprises a separator; The reaction unit is connected to the gas phase treatment unit and the liquid phase separation unit respectively; The gas phase outlet of the reactor is connected to the gas phase inlet of the stripping tower, the gas phase outlet of the stripping tower is connected to the inlet of the reflux device through a condenser, and the liquid phase outlet of the reflux device is connected to the liquid phase inlet of the stripping tower and the liquid phase inlet of the decanter through pipeline I and pipeline II respectively; the oil phase outlet of the decanter is connected to the oil phase inlet of the reactor; A stirrer is provided in the cavity of the reactor; A jacket is provided outside the cavity of the reactor for heating the reactor; The liquid phase outlet of the reactor is connected to the liquid phase inlet of the separator, and the outlet I of the separator is connected to the inlet I of the reactor; The separator also includes a product outlet; The stripping tower is a plate tower; The number of theoretical plates of the plate tower is 8 to 25.

2. The device according to claim 1, characterized in that The decanter also includes a water phase outlet; The liquid phase outlet of the reflux device is connected to pipeline I and pipeline II respectively through pump I.

3. The device according to claim 1, characterized in that The outlet I of the separator is connected to the inlet I of the reactor via a pump II.

4. A method for continuous synthesis of ketal, characterized in that: Passing raw materials containing ketone, alcohol and water-carrying agent into the device according to any one of claims 1 to 3 to synthesize ketal; The water-carrying agent is cyclohexane.

5. The method according to claim 4, characterized in that The ketone is selected from at least one of cyclohexanone, cyclohexanedione, cyclopentanone and butanone; The alcohol is a dihydroxy alcohol compound; The dihydroxy alcohol compound is selected from at least one of ethylene glycol, propylene glycol, butylene glycol and hexylene glycol.

6. The method according to claim 4, characterized in that The method comprises the following steps: (1) adding raw materials from the raw material inlet of the reactor into the reactor containing the catalyst, the raw materials are stirred and mixed by the stirrer in the reactor, and heated to the reaction temperature by the jacket, and react to generate gas phase products and liquid phase products; (2) The gas phase product described in step (1) passes through the stripping tower and is exchanged with the liquid phase refluxed through the reflux device, and the gas phase containing water and water agent is separated from the acetal product; the gas phase containing water and water agent flows through a condenser to condense into a liquid phase, passes through the reflux device, pipeline 1, pipeline 2, returns to the stripping tower, and is sent to a decanter; the liquid phase entering the decanter is separated into an oil phase and a water phase, the oil phase returns to the reactor, and the water phase is discharged as waste water; The liquid product in step (1) enters the separator and is separated by gravity sedimentation to obtain slurry and reaction products. The slurry is returned to the reactor, and the reaction products are discharged from the product outlet of the separator.

7. The method according to claim 6, characterized in that The reaction temperature in step (1) is 90-150 o C.

8. The method according to claim 6, characterized in that In step (2), the pressure of the stripping tower is 101.3-110 kPaA; The top temperature of the stripping tower is 42-75°C; The reflux ratio of the stripping tower is 0.1-30.

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