Separation system and method for preparing acetaldehyde product from ethanol

Abstract

The invention discloses a separation system for preparing acetaldehyde products from ethanol, which comprises a reactor and an ethanol absorption tower, the reactor is connected with the bottom side wall of the ethanol absorption tower, and the tower top of the ethanol absorption tower is sequentially connected with a compressor, a first cooler and a first gas-liquid separation tank; a tower bottom outlet of the ethanol absorption tower is connected with an acetaldehyde rectifying tower through a booster pump, the tower top of the acetaldehyde rectifying tower is sequentially connected with a second cooler, a second gas-liquid separation tank and a reflux pump, and the reflux pump is further connected with the side wall of the top of the acetaldehyde rectifying tower; the tower bottom of the acetaldehyde rectifying tower is respectively connected with the top side wall of the ethanol absorption tower and the inlet of the reactor; and the tower bottom of the acetaldehyde rectifying tower is also provided with an ethanol outlet. Meanwhile, the invention also discloses a method for preparing an acetaldehyde product by separating ethanol by using the system. By adding the ethanol absorption tower, the main product acetaldehyde, the by-product hydrogen and the unreacted ethanol can be efficiently separated, the separation precision is high, and the utilization efficiency of raw materials is high.

Description

technical field

[0001] The invention belongs to the field of separation of acetaldehyde products from ethanol, and in particular relates to a separation system and method for acetaldehyde products from ethanol. Background technique

[0002] Acetaldehyde is an important organic chemical intermediate and is a direct derivative of ethanol, which can be used to produce acetic acid, acetate, pentaerythritol, crotonaldehyde, trichloroacetaldehyde, glyoxal, vinyl acetate and pyridine compounds, etc. It has a wide range of uses in the fields of pesticides, medicine, food and feed additives.

[0003] At present, the industrial production routes of acetaldehyde in the world mainly include the following: ethylene oxidation method, acetylene hydration method, and ethanol method. Among them, the ethanol method is further divided into ethanol oxidation method and ethanol catalytic dehydrogenation method. The ethanol oxidation method is that ethanol vapor is mixed with air on a silver wir...

Examples

Embodiment 1

[0032] A separation system for producing acetaldehyde products from ethanol, comprising a reactor 1 and an ethanol absorption tower 2, the reactor 1 is connected with the bottom side wall of the ethanol absorption tower 2, and the top of the ethanol absorption tower 2 is connected in turn There are a compressor 3, a first cooler 4, and a first gas-liquid separation tank 5;

[0033] The bottom outlet of the ethanol absorption tower 2 is connected with an acetaldehyde rectification tower 7 through a booster pump 6, and the top of the acetaldehyde rectification tower 7 is connected with a second cooler 8 and a second gas-liquid separation tank in turn. 9. The reflux pump 10 is also connected with the top side wall of the acetaldehyde rectifying tower 7; the second gas-liquid separation tank 9 is provided with a gas outlet, and the reflux pump 10 is connected to the The pipeline that distillation tower 7 is connected is also provided with acetaldehyde outlet;

[0034] The bottom ...

Embodiment 2

[0037] On the basis of Example 1, the ethanol absorption tower 2 is provided with 10-20 trays. The acetaldehyde rectifying tower 7 is provided with 10-20 trays.

Embodiment 3

[0039] A method for separating acetaldehyde products from ethanol, using the above-mentioned separation system for acetaldehyde products from ethanol to separate, comprising the following steps:

[0040] (1) Ethanol enters the reactor 1 for dehydrogenation reaction, the temperature in the reactor 1 is 220-300°C, the pressure is 0.05-0.15MPa, and the catalyst used is a Cu-based catalyst;

[0041] The product of ethanol dehydrogenation, according to the mole percentage of 100%, the mole percentage of each substance is as follows:

[0042] Acetaldehyde 15-25%,

[0043] Ether 0.1-0.5%,

[0044] Butyraldehyde 0.1-1%,

[0045] Ethyl acetate 0.1-0.5%,

[0046] Butanol 0.001-0.1%,

[0047] Hydrogen 15-25%,

[0048] The rest are unreacted ethanol;

[0049]Among them, acetaldehyde is used as the main product, and hydrogen is used as a by-product;

[0050] (2) The gaseous product of the dehydrogenation reaction is cooled to 30-50 °C, and enters the bottom of the ethanol absorption...

technical field

[0001] The invention belongs to the field of separation of acetaldehyde products from ethanol, and in particular relates to a separation system and method for acetaldehyde products from ethanol. Background technique

[0002] Acetaldehyde is an important organic chemical intermediate and is a direct derivative of ethanol, which can be used to produce acetic acid, acetate, pentaerythritol, crotonaldehyde, trichloroacetaldehyde, glyoxal, vinyl acetate and pyridine compounds, etc. It has a wide range of uses in the fields of pesticides, medicine, food and feed additives.

[0003] At present, the industrial production routes of acetaldehyde in the world mainly include the following: ethylene oxidation method, acetylene hydration method, and ethanol method. Among them, the ethanol method is further divided into ethanol oxidation method and ethanol catalytic dehydrogenation method. The ethanol oxidation method is that ethanol vapor is mixed with air on a silver wir...

Examples

Embodiment 1

[0032] A separation system for producing acetaldehyde products from ethanol, comprising a reactor 1 and an ethanol absorption tower 2, the reactor 1 is connected with the bottom side wall of the ethanol absorption tower 2, and the top of the ethanol absorption tower 2 is connected in turn There are a compressor 3, a first cooler 4, and a first gas-liquid separation tank 5;

[0033] The bottom outlet of the ethanol absorption tower 2 is connected with an acetaldehyde rectification tower 7 through a booster pump 6, and the top of the acetaldehyde rectification tower 7 is connected with a second cooler 8 and a second gas-liquid separation tank in turn. 9. The reflux pump 10 is also connected with the top side wall of the acetaldehyde rectifying tower 7; the second gas-liquid separation tank 9 is provided with a gas outlet, and the reflux pump 10 is connected to the The pipeline that distillation tower 7 is connected is also provided with acetaldehyde outlet;

[0034] The bottom ...

Embodiment 2

[0037] On the basis of Example 1, the ethanol absorption tower 2 is provided with 10-20 trays. The acetaldehyde rectifying tower 7 is provided with 10-20 trays.

Embodiment 3

[0039] A method for separating acetaldehyde products from ethanol, using the above-mentioned separation system for acetaldehyde products from ethanol to separate, comprising the following steps:

[0040] (1) Ethanol enters the reactor 1 for dehydrogenation reaction, the temperature in the reactor 1 is 220-300°C, the pressure is 0.05-0.15MPa, and the catalyst used is a Cu-based catalyst;

[0041] The product of ethanol dehydrogenation, according to the mole percentage of 100%, the mole percentage of each substance is as follows:

[0042] Acetaldehyde 15-25%,

[0043] Ether 0.1-0.5%,

[0044] Butyraldehyde 0.1-1%,

[0045] Ethyl acetate 0.1-0.5%,

[0046] Butanol 0.001-0.1%,

[0047] Hydrogen 15-25%,

[0048] The rest are unreacted ethanol;

[0049]Among them, acetaldehyde is used as the main product, and hydrogen is used as a by-product;

[0050] (2) The gaseous product of the dehydrogenation reaction is cooled to 30-50 °C, and enters the bottom of the ethanol absorption...

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