A method for co-producing butyl butyrate in a butanol production device

Abstract

The present invention relates to the technical field of catalytic hydrogenation, specifically to a method for co-producing butyl butyrate in a butanol production device, comprising: liquid-phase n-butyraldehyde and circulating hydrogen are injected into an evaporator, and the liquid-phase n-butyraldehyde is completely volatilized into a gas phase; the gas-phase n-butyraldehyde and circulating hydrogen enter a hydrogenation reactor after being heated and heated; the obtained hydrogenation product flows into a gas-liquid separator after heat exchange and condensation; the separated gas and the newly added hydrogen are used together as circulating hydrogen; the separated liquid enters a light-removing tower as a crude product; the crude product with light components removed flows from the light-removing tower into a heavy-removing tower, and a butanol product is obtained at the top of the heavy-removing tower; the materials in the bottom of the heavy-removing tower enter a butyl butyrate tower, and a butyl butyrate product is obtained at the top of the heavy-removing tower. The present invention co-produces butyl butyrate in the butanol production process, realizes the resource utilization of materials to the greatest extent, and allows hydrogen to be recycled, which also reduces the production cost, and has the characteristics of simple process, low cost, high efficiency, etc.

Description

Technical Field

[0001] The invention relates to the technical field of catalytic hydrogenation, in particular to a method for co-producing butyl butyrate with a butanol production device. Background Art

[0002] N-Butanol is mainly used to make plasticizers such as butyric acid, butylamine, melamine formaldehyde resin, butyl acrylate, dibutyl phthalate, etc., and is widely used in various plastics and rubber products. The ethers and amines made from it can be used as latex paints, fabric processing adhesives, pesticides, rubber processing aids, leather treatment agents, etc. Butyl butyrate is a fine chemical product used to make spices, and is also used as a solvent for resins such as nitrocellulose, shellac, rosin, coumarone, and paint solvents.

[0003] The industrial production method of n-butanol is mainly to produce n-butyraldehyde through hydrogenation reaction. However, the butanol production device can only be used to produce butanol, and the non-butanol materials formed in the production process cannot be effectively utilized, which will cause a waste of resources. Based on this, a method for co-producing butyl butyrate in a butanol production device is proposed. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for co-producing butyl butyrate in a butanol production device, which realizes the resource utilization of materials to the greatest extent, allows hydrogen to be recycled, and also reduces production costs. It has the characteristics of simple process, low cost, and high efficiency.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for co-producing butyl butyrate in a butanol production device, comprising the following steps:

[0006] (1) Liquid n-butyraldehyde and circulating hydrogen are injected into the evaporator. Under the heating of the evaporator and the stripping effect of circulating hydrogen, the liquid n-butyraldehyde is completely volatilized into the gas phase;

[0007] (2) The mixed gas formed by the gas phase n-butyraldehyde and the circulating hydrogen enters the heater to be heated and then enters the hydrogenation reactor to undergo a hydrogenation reaction;

[0008] (3) The obtained hydrogenation product is heat exchanged with the circulating hydrogen flowing to the evaporator through a heat exchanger, and then condensed by a condenser and flows into a gas-liquid separator for gas-liquid separation;

[0009] (4) The separated gas and the newly added hydrogen are used as circulating hydrogen and injected into the evaporator under the action of the compressor; the separated liquid is sent to the light removal tower as the crude product to remove the light components;

[0010] (5) the crude product after light components are removed flows from the light components removal column into the heavy components removal column, where the butanol and heavy components therein are effectively separated, and the butanol product is obtained at the top of the heavy components removal column;

[0011] (6) The materials from the bottom of the deheaving tower enter the No. 1 butyl butyrate tower to continue removing butanol. The materials from the bottom of the No. 1 butyl butyrate tower enter the No. 2 butyl butyrate tower, where butyl butyrate and other heavy components are effectively separated, and the butyl butyrate product is obtained at the top of the No. 2 butyl butyrate tower.

[0012] Preferably, in step (1), the flow rate of n-butyraldehyde is 45 t / h, and the flow rate of circulating hydrogen is 1125 kg / h.

[0013] Preferably, in step (1), the heating temperature of the evaporator is 95-102°C.

[0014] Preferably, in step (2), the temperature of the mixed gas after heating is higher than the dew point temperature of n-butyraldehyde by more than 15°C.

[0015] Preferably, in step (2), in the hydrogenation reactor, the hydrogenation catalyst is hydrogenation-X1, the hydrogenation reaction temperature is 240-250° C., and the hydrogenation reaction pressure is 0.38-0.45 MPa.

[0016] Preferably, in step (3), the cooling temperature of the condenser is 6-10°C.

[0017] Preferably, in step (4), the pressure of the compressor is 0.40-0.46 MPa.

[0018] Preferably, in step (5), the pressure of the lightness removal tower is 30 KPa, and the bottom temperature is 130-135°C; the pressure of the heavyness removal tower is 27 KPa, and the bottom temperature is 132-138°C; the pressure of the No. 1 butyl butyrate tower is -70 KPa, and the bottom temperature is 140-150°C; the pressure of the No. 2 butyl butyrate tower is -80 KPa, and the bottom temperature is 145-155°C.

[0019] Preferably, in steps (4) to (6), the light-removal tower, heavy-removal tower and butyl butyrate tower are all high-efficiency plate-type distillation towers.

[0020] The present invention provides a method for co-producing butyl butyrate in a butanol production device, which has the following beneficial effects compared with the prior art:

[0021] The present invention co-produces butyl butyrate in the butanol production process, separates the by-product butyl butyrate as a heavy component, so as to realize the resource utilization of materials to the greatest extent, and allows hydrogen to be recycled, thereby reducing the production cost. The present invention has the characteristics of simple process, low cost, high efficiency and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0023] Figure 1 The present invention is a flow chart of the butanol production device for co-producing butyl butyrate. DETAILED DESCRIPTION

[0024] The following examples are used to explain the implementation methods of the present application in detail, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0025] A method for co-producing butyl butyrate in a butanol production device comprises the following steps:

[0026] (1) Liquid n-butyraldehyde and circulating hydrogen are injected into the evaporator. Under the heating of the evaporator and the stripping effect of circulating hydrogen, the liquid n-butyraldehyde is completely volatilized into the gas phase;

[0027] The flow rate of n-butyraldehyde is 45t / h, and the flow rate of circulating hydrogen is 1125kg / h; the temperature of circulating hydrogen after heat exchange is between 90-95°C; and the heating temperature of the evaporator is 95-102°C.

[0028] (2) The mixed gas formed by the gas phase n-butyraldehyde and the circulating hydrogen enters the heater to be heated and then enters the hydrogenation reactor to undergo a hydrogenation reaction;

[0029] The temperature of the mixed gas after heating is higher than the dew point temperature of n-butyraldehyde by more than 15°C; in the hydrogenation reactor, the hydrogenation catalyst is hydrogenation-X1, the hydrogenation reaction temperature is 240-250°C, and the hydrogenation reaction pressure is 0.38-0.45MPa.

[0030] (3) The obtained hydrogenation product is heat exchanged with the circulating hydrogen flowing to the evaporator through a heat exchanger, and then condensed by a condenser and flows into a gas-liquid separator for gas-liquid separation; the cooling temperature of the condenser is 6-10°C.

[0031] (4) The separated gas and the newly added hydrogen are used together as circulating hydrogen and injected into the evaporator under the action of the compressor; the separated liquid enters the light-removal tower (high-efficiency plate distillation tower) as the crude product to remove the light components (including n-butyraldehyde, isobutyraldehyde and water); the pressure of the compressor is 0.40-0.46MPa; the pressure of the light-removal tower is 30KPa, and the temperature of the tower bottom is 130-135℃.

[0032] (5) The crude product after light components are removed flows from the light components removal tower (high-efficiency plate distillation tower) into the heavy components removal tower (high-efficiency plate distillation tower), where the butanol and heavy components (including butyric acid, butyl butyrate, and butyl isobutyrate) are effectively separated, and a butanol product is obtained at the top of the heavy components removal tower with an output of 20 t / h. The pressure of the heavy components removal tower is 27 KPa, and the bottom temperature is 132-138°C.

[0033] (6) The materials in the bottom of the de-heavy tower enter the No. 1 butyl butyrate tower (high-efficiency plate distillation tower) to continue to remove butanol, and the materials in the bottom of the No. 1 butyl butyrate tower enter the No. 2 butyl butyrate tower (high-efficiency plate distillation tower), where butyl butyrate and other heavy components are effectively separated, and butyl butyrate products are obtained at the top of the No. 2 butyl butyrate tower. The pressure of the No. 1 butyl butyrate tower is -70KPa, and the bottom temperature is 140-150°C; the pressure of the No. 2 butyl butyrate tower is -80KPa, and the bottom temperature is 145-155°C.

[0034] By adopting the method for co-producing butyl butyrate with the butanol production device, the output of the butanol product is 20 t / h, and the output of the butyl butyrate product is 0.2 t / h.

[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for co-producing butyl butyrate in a butanol production device, characterized in that: The following steps are involved: (1) Liquid n-butyraldehyde and circulating hydrogen are injected into the evaporator. Under the heating of the evaporator and the stripping effect of circulating hydrogen, the liquid n-butyraldehyde is completely volatilized into the gas phase; (2) The mixed gas formed by the gas phase n-butyraldehyde and the circulating hydrogen enters the heater to be heated and then enters the hydrogenation reactor to undergo a hydrogenation reaction; (3) The obtained hydrogenation product is heat exchanged with the circulating hydrogen flowing to the evaporator through a heat exchanger, and then condensed by a condenser and flows into a gas-liquid separator for gas-liquid separation; (4) The separated gas and the newly added hydrogen are used as circulating hydrogen and injected into the evaporator under the action of the compressor; the separated liquid is sent to the light removal tower as the crude product to remove the light components; (5) the crude product after light components are removed flows from the light components removal column into the heavy components removal column, where the butanol and heavy components therein are effectively separated, and the butanol product is obtained at the top of the heavy components removal column; (6) The materials from the bottom of the deheaving tower enter the No. 1 butyl butyrate tower to continue removing butanol. The materials from the bottom of the No. 1 butyl butyrate tower enter the No. 2 butyl butyrate tower, where butyl butyrate and other heavy components are effectively separated, and the butyl butyrate product is obtained at the top of the No. 2 butyl butyrate tower.

2. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (1), the flow rate of n-butyraldehyde is 45 t / h, and the flow rate of circulating hydrogen is 1125 kg / h.

3. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (1), the heating temperature of the evaporator is 95-102°C.

4. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (2), the temperature of the mixed gas after heating is higher than the dew point temperature of n-butyraldehyde by more than 15°C.

5. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (2), in the hydrogenation reactor, the hydrogenation reaction temperature is 240-250° C., and the hydrogenation reaction pressure is 0.38-0.45 MPa.

6. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (3), the cooling temperature of the condenser is 6-10°C.

7. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (4), the pressure of the compressor is 0.40-0.46 MPa.

8. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In step (5), the pressure of the lightness removal tower is 30 KPa, and the bottom temperature is 130-135°C; the pressure of the heavyness removal tower is 27 KPa, and the bottom temperature is 132-138°C; the pressure of the No. 1 butyl butyrate tower is -70 KPa, and the bottom temperature is 140-150°C; the pressure of the No. 2 butyl butyrate tower is -80 KPa, and the bottom temperature is 145-155°C.

9. The method for co-producing butyl butyrate in a butanol production device according to claim 1, characterized in that: In steps (4) to (6), the light-removal tower, heavy-removal tower and butyl butyrate tower are all high-efficiency plate-type distillation towers.

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