Method and device for continuously treating hydroformylation reaction product and application

Abstract

The invention provides a method and device for continuously treating a hydroformylation reaction product and application, and the method comprises the following steps: a) reducing the pressure of a hydroformylation liquid product to 2.5-5.5 Mpa in a first pressure reduction separation unit, and then carrying out gas-liquid separation to separate a gas phase and a liquid phase; b) reducing the pressure to 0.5-2.5 Mpa in a second pressure reduction separation unit, and then carrying out gas-liquid separation to separate a gas phase and a liquid phase; c) cooling the hydroformylation gas-phase product, separating a gas phase and a liquid phase, emptying the gas phase as high-pressure emptying gas, and feeding the liquid phase into a second depressurization separation unit; and d) further separating a crude product containing low-boiling-point byproducts and unreacted raw materials from the liquid phase after depressurization separation, and mainly containing high-boiling-point byproducts, a hydroformylation catalyst and a solvent. The method provided by the invention can be used for comprehensively treating multiple streams of gas-phase and liquid-phase discharges from multiple reaction units, so that the loss of the catalyst along with gas-phase discharge is reduced, and meanwhile, the product yield is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of hydroformylation reaction product treatment, and in particular relates to a method, a device and an application of continuously treating hydroformylation reaction products. Background Art

[0002] The preparation of the corresponding aldehyde by hydroformylation reaction is very important in chemical production, so there are many studies on the hydroformylation method worldwide. The present invention relates to a method for comprehensively treating the effluent in the continuous hydroformylation reaction of vinyl acetate, and the effluent includes gaseous effluent and liquid effluent. The gaseous effluent mainly contains synthesis gas, low boiling point by-products, a small amount of hydroformylation catalyst, etc.; the liquid effluent mainly includes aldehyde, high boiling point by-products, hydroformylation catalyst, unreacted raw materials, low boiling point by-products and dissolved synthesis gas.

[0003] Chinese patent CN1223568A discloses a method of first performing two-stage decompression, and then contacting the gas-liquid two-phase flow obtained after the second stage decompression in a countercurrent manner in a stripping tower to achieve separation of the catalyst and the product aldehyde. This method lacks comprehensive treatment of the catalyst that may be entrained in the gas phase discharge, and the gas phase is not further treated after the first stage decompression, resulting in product loss.

[0004] In view of the above problems, the present invention provides a method for comprehensively treating effluent from vinyl acetate hydroformylation, which can comprehensively treat gaseous effluent and liquid effluent from multiple hydroformylation reaction units, reduce the loss of catalyst with gaseous phase discharge, and reduce the loss of products and raw materials. Summary of the invention

[0005] The present invention provides a method and device for continuously treating hydroformylation reaction products, which can comprehensively treat gaseous effluents and liquid effluents from multiple hydroformylation reaction units. The effluents include gaseous effluents and liquid effluents. The gaseous effluents mainly contain synthesis gas, low-boiling point by-products, a small amount of hydroformylation catalyst, etc.; the liquid effluents mainly contain aldehydes, high-boiling point by-products, hydroformylation catalysts, unreacted raw materials, low-boiling point by-products and dissolved synthesis gas.

[0006] One of the objects of the present invention is to provide a method for continuously treating a hydroformylation reaction product, comprising:

[0007] (1) performing gas-liquid separation on the hydroformylation reaction product obtained by the hydroformylation reaction to obtain a gas phase component G1 and a liquid phase component L1;

[0008] (2) cooling the gas phase component G1 obtained in step (1), and then performing gas-liquid separation to obtain a gas phase component G2 and a liquid phase component L2, wherein the gas phase component G2 is discharged;

[0009] (3) The liquid component L1 obtained in step (1) is subjected to a pressure reduction operation and gas-liquid separation to obtain a gas component G' and a liquid component L'. The obtained liquid component L' is subjected to separation treatment to obtain a crude aldehyde product and a mixture containing a hydroformylation catalyst and a solvent.

[0010] According to the present invention, in the method for continuously treating the hydroformylation reaction product:

[0011] The hydroformylation reaction product may be a mixture obtained after any hydroformylation reaction in the art. In the present invention, the hydroformylation reaction product is a reaction product of vinyl acetate and synthesis gas, wherein the synthesis gas may be synthesis gas of various specifications commonly used in the art, for example, the synthesis gas contains hydrogen and carbon monoxide, preferably, the molar ratio of hydrogen to carbon monoxide in the synthesis gas is (0.5-5):1, more preferably, the molar ratio of hydrogen to carbon monoxide in the synthesis gas is (0.5-2):1, and the synthesis gas may be present in the hydroformylation liquid phase discharge in the form of dissolved or bubbled form;

[0012] The gas phase component G1 of the hydroformylation reaction product mainly includes hydrogen, carbon monoxide, a hydroformylation catalyst, and low boiling point by-products, and the liquid phase component L1 mainly includes aldehydes, high boiling point by-products, a hydroformylation catalyst, unreacted raw materials, low boiling point by-products and dissolved synthesis gas, wherein the low boiling point by-products include acetic acid, ethyl acetate, ethylene, etc., and the high boiling point by-products include aldehyde oligomers, etc. The solvent can be a high boiling point inert solvent, such as o-dichlorobenzene, or other organic solvents commonly used in the art;

[0013] The hydroformylation catalyst can be a catalyst commonly used in the art. For example, the hydroformylation catalyst is selected from at least one compound containing metal rhodium and / or cobalt, preferably at least one of octacarbonyl cobalt and L-coordinated tricarbonyl hydride rhodium (HRh(CO)3L).

[0014] According to the present invention, in the method for continuously treating the hydroformylation reaction product:

[0015] The temperature of the hydroformylation reaction product in step (1) is 50 to 150° C. and the pressure is 0.5 to 8 MPa;

[0016] In step (2), the temperature of the gas phase component G1 after cooling is 20 to 80° C., preferably 20 to 60° C.;

[0017] The pressure reduction operation in step (3) includes at least two stages of pressure reduction process;

[0018] The mixture containing the hydroformylation catalyst and the solvent obtained in step (3) is optionally partially or completely recycled to the hydroformylation reaction unit.

[0019] According to the present invention, in the method for continuously treating the hydroformylation reaction product, the step (3) specifically comprises:

[0020] a) subjecting the liquid phase component L1 to first-stage decompression and flash evaporation to obtain a gas phase component G3 and a liquid phase component L3;

[0021] b) The liquid phase component L3 is subjected to the second stage of decompression and flash evaporation to obtain the gas phase component G4 and the liquid phase component L4;

[0022] c) combining the gas phase component G3 and the gas phase component G4, cooling them, and then separating the gas and liquid to obtain the gas phase component G5 and the liquid phase component L5, and discharging the gas phase component G5;

[0023] d) The liquid phase component L5 is combined with the liquid phase component L4 and separated to obtain a crude aldehyde product and a mixture containing a hydroformylation catalyst and a solvent.

[0024] According to the present invention, in the above step (3):

[0025] In step a), the pressure of the liquid component L1 after the first stage of decompression is 2.5 to 5.5 MPa, preferably 3 to 4.5 MPa;

[0026] Step b) the pressure of the liquid component L3 after the second stage of decompression is 0.5-2.5 MPa, preferably 0.5-2 MPa;

[0027] The flash evaporation operation in step a) and step b) is not particularly limited, and the flash evaporation operation method commonly used in the art can be adopted;

[0028] In step c), the temperature of the gas phase component G3 and the gas phase component G4 after cooling is 20 to 80° C., preferably 20 to 60° C.;

[0029] The separation in step d) can adopt the separation equipment and separation conditions commonly used in the prior art, for example, a separation tower can be used. Specifically, the conditions of the separation tower are: tower top temperature 80-120°C, tower bottom temperature 90-150°C, pressure 10-200KPa, and tower plate number 5-40.

[0030] According to a specific embodiment of the present invention, the method for continuously treating the hydroformylation reaction product is specifically completed by the following steps:

[0031] a) reducing the pressure of the hydroformylation reaction liquid discharge L1 to 2.5-5.5 MPa in a first depressurization separation unit, and then performing gas-liquid separation to separate a gas phase G3 containing synthesis gas, low-boiling point by-products, a small amount of aldehyde products and unreacted raw materials, and a liquid phase L3 containing aldehyde products, high-boiling point by-products, hydroformylation reaction catalyst and solvent;

[0032] b) the liquid phase L3 obtained in the first depressurization separation unit is reduced to 0.5-2.5 MPa in the second depressurization separation unit, and then subjected to gas-liquid separation to separate a gas phase G4 containing synthesis gas, low-boiling point by-products, a small amount of aldehyde products and unreacted raw materials; the gas phase composition obtained in the first depressurization separation unit and the second depressurization separation unit mainly contains synthesis gas and part of the low-boiling point by-products, and these two parts of gas phase G3 and G4 are cooled and then enter the second separation unit to separate the gas phase G5 as low-pressure vent gas and discharge it to the outside, and the liquid phase L5 is recovered and sent to the third separation unit;

[0033] c) cooling the gaseous phase effluent G1 from the hydroformylation reaction and then sending it into the first separation unit to separate the gaseous phase G2 and the liquid phase L2, wherein the gaseous phase G2 is discharged as high-pressure vent gas and the liquid phase L2 is sent to the second pressure reduction separation unit;

[0034] d) After two-stage depressurization, the liquid phase L4 is sent to a third separation unit for separation, and a crude product containing a small amount of low-boiling point by-products and unreacted raw materials and a mixture mainly containing high-boiling point by-products, hydroformylation catalyst and solvent are separated in the third separation unit.

[0035] A second object of the present invention is to provide an apparatus for continuously treating a hydroformylation reaction product, for implementing the above-mentioned method for continuously treating a hydroformylation reaction product.

[0036] According to the present invention, the device for continuously treating the hydroformylation reaction product comprises: a first cooling unit and a first separation unit connected in sequence by pipelines from the gas phase component G1 outlet of the hydroformylation reaction product, and a pressure reduction separation system, a second cooling unit and a separation system connected by pipelines from the liquid phase component L1 outlet of the hydroformylation reaction product.

[0037] According to a specific embodiment of the present invention, the outlet of the liquid component L1 of the hydroformylation reaction product is sequentially connected to the first depressurization separation unit, the second depressurization separation unit, the second cooling unit, the second separation unit, and the third separation unit by pipelines.

[0038] According to the present invention, in the device for continuously treating the hydroformylation reaction product:

[0039] The first depressurization separation unit and the second depressurization separation unit respectively include a depressurization device and a flash tank; the depressurization device can be a depressurization device commonly used in the prior art, such as a depressurization valve; the flash tank is not particularly limited, and can be a flash tank commonly used in the prior art;

[0040] The first separation unit is provided with a gas phase G2 outlet and a liquid phase L2 outlet, wherein the liquid phase L2 outlet is connected to the material inlet of the second pressure reduction separation unit through a pipeline;

[0041] The first depressurization and separation unit is provided with a gas phase G3 outlet and a liquid phase L3 outlet, wherein the gas phase G3 outlet is connected to the second cooling unit and the second separation unit in sequence by a pipeline, and the liquid phase L3 outlet is connected to the material inlet of the second depressurization and separation unit by a pipeline;

[0042] The second pressure reduction separation unit is provided with a gas phase G4 outlet and a liquid phase L4 outlet, wherein the gas phase G4 outlet is connected to the material inlet of the second cooling unit through a pipeline, and the liquid phase L4 outlet is connected to the material inlet of the third separation unit through a pipeline;

[0043] The second separation unit is provided with a gas phase G5 outlet and a liquid phase L5 outlet, wherein the liquid phase L5 outlet is connected to the material inlet of the third separation unit through a pipeline;

[0044] The third separation unit is provided with an outlet for a crude aldehyde product and an outlet for a mixture containing a hydroformylation catalyst and a solvent. Preferably, the outlet for the mixture containing a hydroformylation catalyst and a solvent is optionally provided with a pipeline connected to a hydroformylation reaction unit.

[0045] A third object of the present invention is to provide an application of the method or device for continuously treating a hydroformylation reaction product in treating a hydroformylation reaction product.

[0046] The method for continuously treating the hydroformylation reaction product provided by the present invention can comprehensively treat multiple gas phase effluents and liquid phase effluents from multiple reaction units, and comprehensively treat the liquid phase effluent while recovering the catalyst and unreacted raw materials entrained in the gas phase effluent to the maximum extent. A multi-stage pressure reduction method is adopted to avoid the loss of products and unreacted raw materials during the pressure reduction process, and reasonable coupling is performed in the gas phase and liquid phase effluent treatment process, so as to fully utilize the equipment processing capacity and further improve the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The following is a simplified process flow diagram of the method for continuously treating the hydroformylation reaction product used in the embodiment.

[0048] Figure 2 The following is a simplified process flow diagram of the method for treating the hydroformylation reaction product used in the comparative example.

[0049] Description of reference numerals:

[0050] 1-first pressure reduction separation unit, 2-second pressure reduction separation unit; 3-second separation unit, 4-first separation unit, 5-hydroformylation reaction liquid phase component L1, 6-hydroformylation reaction gas phase component G1, 7-gas phase component G2 separated by the first separation unit, 8-gas phase component G5 separated by the second separation unit, 9-liquid phase component L5 separated by the second separation unit, 10-third separation unit, 11-crude product, 12-mixture containing hydroformylation catalyst and solvent, 13-first cooling unit, 14-second cooling unit. DETAILED DESCRIPTION

[0051] The present invention is described in detail below in conjunction with specific embodiments and drawings. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the content of the present invention still fall within the scope of protection of the present invention.

[0052] The raw materials used in the examples and comparative examples, unless otherwise specified, are disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0053] The present invention uses a device for continuously treating the hydroformylation reaction product such as Figure 1As shown, it includes: a first cooling unit 13 and a first separation unit 4 connected in sequence by pipelines from the gas phase component G1 outlet 6 of the hydroformylation reaction product, and a first pressure reduction separation unit 1, a second pressure reduction separation unit 2, a second cooling unit 14, a second separation unit 3, and a third separation unit 10 connected in sequence by pipelines from the liquid phase component L1 outlet 5 of the hydroformylation reaction product. Among them, the first pressure reduction separation unit 1 and the second pressure reduction separation unit 2 respectively include a pressure reduction device and a flash tank (this embodiment adopts a pressure reduction valve and a flash tank commonly used in the art, which are common equipment or devices and are not shown in the figure); the first separation unit 4 is provided with a gas phase G2 outlet and a liquid phase L2 outlet, wherein the liquid phase L2 outlet is connected to the material inlet of the second pressure reduction separation unit 2 through a pipeline; the first pressure reduction separation unit 1 is provided with a gas phase G3 outlet and a liquid phase L3 outlet, wherein the gas phase G3 outlet is connected to the second cooling unit 14 and the second separation unit 3 in sequence by a pipeline, and the liquid phase L3 outlet is connected to the material inlet of the second pressure reduction separation unit 2 through a pipeline. The pipeline is connected to the material inlet of the second pressure reduction separation unit 2; the second pressure reduction separation unit 2 is provided with a gas phase G4 outlet and a liquid phase L4 outlet, wherein the gas phase G4 outlet is connected to the material inlet of the second cooling unit 14 through a pipeline, and the liquid phase L4 outlet is connected to the material inlet of the third separation unit 10 through a pipeline; the second separation unit is provided with a gas phase G5 outlet 8 and a liquid phase L5 outlet 9, wherein the liquid phase L5 outlet 9 is connected to the material inlet of the third separation unit 10 through a pipeline; the third separation unit 10 is provided with an aldehyde product crude product outlet 11, and an outlet 12 containing a hydroformylation catalyst and a solvent.

[0054] Example 1

[0055] The method for continuously treating the hydroformylation reaction product provided by the present invention is as follows Figure 1 The process shown is carried out.

[0056] 4554.86 kg / h of hydroformylation liquid discharge L1 (composed of 0.48 wt% of vinyl acetate, 2.56 wt% of acetic acid, 2.34 wt% of ethyl acetate, 52.44 wt% of 3-acetoxypropionaldehyde, 38.24 wt% of 2-acetoxypropionaldehyde, 2.8 wt% of cobalt-based catalyst, 0.04 wt% of hydrogen, 0.25 wt% of carbon monoxide, and 0.85 wt% of ethylene) at a temperature of 102°C and a pressure of 6.98 MPa, is depressurized to 3.5 MPa in the first stage and then enters a flash tank, from which 4540.28 kg / h of liquid phase L3 is discharged. The liquid phase L3 is depressurized to 1.0 MPa in the second stage and then enters a flash tank, from which 44521.86 kg / h of liquid phase L4 is discharged. After the first and second stage decompression, the flash tank discharges a total of 30.01 kg / h of gas phases G3 and G4 (mainly unreacted synthesis gas and low-boiling by-products, part of unreacted raw materials and products). After cooling to 40°C, the liquid phase L53.48 kg / h (mainly products and unreacted raw materials) is recovered and sent to the third separation unit (separation tower) 10. The uncondensed gas phase G5 (39°C, 1 MPa, mainly synthesis gas and low-boiling by-products) is discharged as low-pressure vent gas, which is 26.53 kg / h. The hydroformylation gas discharge G1 (composed of 0.29 wt% of vinyl acetate, 0.37 wt% of acetic acid, 1.37 wt% of ethyl acetate, 2.15 wt% of 3-acetoxypropionaldehyde, 3.23 wt% of 2-acetoxypropionaldehyde, 12.3 wt% of hydrogen, 52.5 wt% of carbon monoxide, and 27.78 wt% of ethylene) with a temperature of 102° C., a pressure of 6.98 MPa, and a temperature of 27.23 kg / h was cooled to 40° C. to obtain a liquid phase L2 of 3.73 kg / h (mainly aldehyde products and part of the entrained catalyst), which was sent to the second pressure reduction separation unit to be combined with the liquid phase L3 for further treatment. The uncondensed gas phase G2 (39° C., 6.98 MPa, 41.93 kg / h) was discharged as high-pressure vent gas (mainly synthesis gas and low-boiling by-products), and the liquid phase L2 was sent to the second slurry separation unit. The liquid phase L4 and liquid phase L5 obtained after the above treatment are combined and sent to the third separation unit (separation tower) 10 at 4529.1 kg / h, wherein the top temperature of the separation tower 10 is 97.7°C, the bottom temperature is 123.4°C, the pressure is 30 kPa, the number of plates is 23, and part of the crude acetoxypropionaldehyde product is refluxed at the top of the tower, and the reflux ratio is 1, so that the crude acetoxypropionaldehyde product and unreacted vinyl acetate are mainly extracted from the top of the tower, and the top extraction rate is 3644.14 kg / h. A mixture 12 (catalyst solution) containing a catalyst (cobalt-based catalyst) and a solvent is extracted from the bottom of the separation tower 10, and the extraction rate is 841 kg / h. The catalyst solution is returned to the hydroformylation unit for use.

[0057] During the above treatment process, 0.20 kg / h of vinyl acetate raw material and 0.45 kg / h of acetoxypropionaldehyde were lost in the venting air.

[0058] Example 2

[0059] The process of Example 1 was followed, except that:

[0060] 4508.9 kg / h of hydroformylation liquid discharge L1 (composed of 0.38 wt% of vinyl acetate, 2.56 wt% of acetic acid, 2.33 wt% of ethyl acetate, 52.38 wt% of 3-acetoxypropionaldehyde, 38.67 wt% of 2-acetoxypropionaldehyde, 2.54 wt% of rhodium catalyst, 0.03 wt% of hydrogen, 0.48 wt% of carbon monoxide, and 0.64 wt% of ethylene) at a temperature of 107°C and a pressure of 6.48 MPa enters a flash tank after being decompressed to a pressure of 3.0 MPa in the first stage. 4491.14 kg / h of liquid phase L3 discharged from the flash tank is decompressed to a pressure of 1.5 MPa in the second stage and enters a flash tank. 44480.62 kg / h of liquid phase L is discharged after the second stage decompression. After the first and second stage decompression, the flash tank discharges a total of 28029 kg / h of gas phases G3 and G4 (mainly unreacted synthesis gas and low-boiling by-products, part of unreacted raw materials and products), and after cooling to 35°C, recovers 32.61 kg / h of liquid phase L5 (mainly products and unreacted raw materials) and sends it to the third separation unit (separation tower) 10. The uncondensed gas phase G5 (35°C, 1.5 MPa, mainly synthesis gas and low-boiling by-products) is discharged as low-pressure vent gas, which is 25.68 kg / h. The hydroformylation gas discharge G1 (composed of 1.21 wt% vinyl acetate, 0.30 wt% acetic acid, 1.07 wt% ethyl acetate, 1.80 wt% 3-acetoxypropionaldehyde, 2.71 wt% 2-acetoxypropionaldehyde, 5.52 wt% hydrogen, 70.06 wt% carbon monoxide, 17.3 wt% ethylene) with a temperature of 107°C, a pressure of 6.48 MPa, and 145.08 kg / h is cooled to 35°C to obtain a liquid phase L28.55 kg / h (mainly aldehyde products and part of the entrained catalyst) which is fed into the second pressure reduction separation unit, and the uncondensed gas phase G2 (35°C, 6.48 MPa, 136.53 kg / h) is discharged as high-pressure vent gas (mainly synthesis gas and low-boiling point by-products). After treatment, liquid phases L4 and L5 are combined and sent to the third separation unit (separation tower) 10 at 4491.77 kg / h, wherein the top temperature of the separation tower 10 is 97.5°C, the bottom temperature is 122°C, the pressure is 30 kPa, the number of plates is 23, and part of the crude acetoxypropionaldehyde product is refluxed at the top of the tower, and the reflux ratio is 1, so that the crude acetoxypropionaldehyde product and unreacted vinyl acetate are mainly extracted from the top of the tower, and the top extraction rate is 3645.97 kg / h. The catalyst solution 12 is extracted from the bottom of the separation tower 10, and the extraction rate is 800 kg / h. The catalyst solution is returned to the hydroformylation unit for use.

[0061] During the above treatment process, 0.37 kg / h of vinyl acetate raw material and 0.50 kg / h of acetoxypropionaldehyde were lost in the venting air.

[0062] Comparative Example

[0063] The comparative example provided by the present invention is according to Figure 2 The process shown is carried out.

[0064] 4554.86 kg / h of hydroformylation liquid discharge 5 (composed of 0.48 wt% of vinyl acetate, 2.56 wt% of acetic acid, 2.34 wt% of ethyl acetate, 52.44 wt% of 3-acetoxypropionaldehyde, 38.24 wt% of 2-acetoxypropionaldehyde, 2.8 wt% of cobalt-based catalyst, 0.04 wt% of hydrogen, 0.25 wt% of carbon monoxide, and 0.85 wt% of ethylene) at a temperature of 102°C and a pressure of 6.98 MPa, is depressurized to 3.5 MPa in the first stage and then enters a flash tank. 4540.28 kg / h of liquid phase discharged from the flash tank is depressurized to 1.0 MPa in the second stage and then enters a flash tank. 4521.86 kg / h of liquid phase after the second stage depressurization is discharged. After the primary and secondary decompression, the flash tank discharges a total of 29.99 kg / h of gas phase (mainly unreacted synthesis gas and low-boiling by-products, part of unreacted raw materials and products), and after cooling to 40°C, 3.48 kg / h of liquid phase (mainly products and unreacted raw materials) is recovered and sent to the separation tower 10. The uncondensed gas phase at 39°C, 1 MPa, and 26.52 kg / h (mainly synthesis gas and low-boiling by-products) is discharged as low-pressure vent air. The hydroformylation gas discharge 6 (composed of 0.29 wt% of vinyl acetate, 0.37 wt% of acetic acid, 1.37 wt% of ethyl acetate, 2.15 wt% of 3-acetoxypropionaldehyde, 3.23 wt% of 2-acetoxypropionaldehyde, 12.3 wt% of hydrogen, 52.5 wt% of carbon monoxide and 27.78 wt% of ethylene) at a temperature of 102° C., a pressure of 6.98 MPa and a temperature of 27.23 kg / h is cooled to 40° C., and 4.07 kg / h of liquid phase (mainly aldehyde products and part of the entrained catalyst) is fed into the separation tower 10, and the uncondensed gas phase at 39° C., 6.98 MPa and a temperature of 39.07 kg / h is discharged as high-pressure vent gas (mainly synthesis gas and low-boiling by-products). After treatment, three liquid phases are combined and sent to the separation tower 10 at a rate of 4529.4 kg / h, wherein the top temperature of the separation tower 10 is 97.7°C, the bottom temperature is 123.4°C, the pressure is 30 kPa, the number of plates is 23, and part of the crude acetoxypropionaldehyde product is refluxed at the top of the tower, and the reflux ratio is 1, so that the crude acetoxypropionaldehyde product and unreacted vinyl acetate are mainly extracted from the top of the tower, and the top extraction rate is 3644.14 kg / h. The catalyst solution 12 is extracted from the bottom of the separation tower 10, and the extraction rate is 841 kg / h. The catalyst solution is returned to the hydroformylation unit for use.

[0065] During the above treatment process, 0.71 kg / h of vinyl acetate raw material and 0.52 kg / h of acetoxypropionaldehyde were lost in the venting air.

[0066] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for continuously treating a hydroformylation reaction product, comprising: (1) performing gas-liquid separation on the hydroformylation reaction product obtained by the hydroformylation reaction to obtain a gas phase component G1 and a liquid phase component L1; (2) cooling the gas phase component G1 obtained in step (1), and then performing gas-liquid separation to obtain a gas phase component G2 and a liquid phase component L2, wherein the gas phase component G2 is discharged; (3) The liquid component L1 obtained in step (1) is subjected to a pressure reduction operation and gas-liquid separation to obtain a gas component G' and a liquid component L'. The obtained liquid component L' is subjected to separation treatment to obtain a crude aldehyde product and a mixture containing a hydroformylation catalyst and a solvent.

2. The method according to claim 1, characterized in that The hydroformylation reaction product is a reaction product of vinyl acetate and synthesis gas, wherein the synthesis gas contains hydrogen and carbon monoxide, and preferably, the molar ratio of hydrogen to carbon monoxide in the synthesis gas is (0.5-5):1; and / or, The hydroformylation catalyst is selected from at least one of compounds containing metal rhodium and / or cobalt, preferably at least one of octacarbonyl cobalt and L-coordinated tricarbonyl rhodium hydride.

3. The method according to claim 1, characterized in that The temperature of the hydroformylation reaction product in step (1) is 50 to 150° C., and / or the pressure is 0.5 to 8 MPa; and / or, The temperature of the gas phase component G1 after cooling in step (2) is 20 to 80° C., preferably 20 to 60° C.; and / or, The pressure reduction operation in step (3) includes at least two-stage pressure reduction processes; and / or, The mixture containing the hydroformylation catalyst and the solvent obtained in step (3) is optionally partially or completely recycled to the hydroformylation reaction unit.

4. The method according to claim 1, characterized in that: The step (3) specifically includes: a) subjecting the liquid phase component L1 to first-stage decompression and flash evaporation to obtain a gas phase component G3 and a liquid phase component L3; b) The liquid phase component L3 is subjected to the second stage of decompression and flash evaporation to obtain the gas phase component G4 and the liquid phase component L4; c) combining the gas phase component G3 and the gas phase component G4, cooling them, and then separating the gas and liquid to obtain the gas phase component G5 and the liquid phase component L5, and the gas phase component G5 is discharged; d) The liquid phase component L5 is combined with the liquid phase component L4 and separated to obtain a crude aldehyde product and a mixture containing a hydroformylation catalyst and a solvent.

5. The method according to claim 4, characterized in that In step a), the pressure of the liquid component L1 after the first stage of decompression is 2.5 to 5.5 MPa, preferably 3 to 4.5 MPa; and / or, Step b) the pressure of the liquid component L3 after the second stage of decompression is 0.5-2.5 MPa, preferably 0.5-2 MPa; and / or, In step c), the temperature of the gas phase component G3 and the gas phase component G4 after cooling is 20 to 80° C., preferably 20 to 60° C.; and / or, In step d), separation is performed using a separation tower. Preferably, the conditions of the separation tower are: a tower top temperature of 80 to 120° C., and / or a tower bottom temperature of 90 to 150° C., and / or a pressure of 10 to 200 KPa, and / or a tower plate number of 5 to 40.

6. A device for continuously treating a hydroformylation reaction product, used to implement the method for continuously treating a hydroformylation reaction product according to any one of claims 1 to 5.

7. The device according to claim 6, characterized in that The device comprises: a first cooling unit and a first separation unit connected in sequence by pipelines from the gas phase component G1 outlet of the hydroformylation reaction product, and a pressure reduction separation system, a second cooling unit and a separation system connected by pipelines from the liquid phase component L1 outlet of the hydroformylation reaction product.

8. The device according to claim 7, characterized in that The outlet of the liquid component L1 of the hydroformylation reaction product is connected to the first pressure reduction separation unit, the second pressure reduction separation unit, the second cooling unit, the second separation unit, and the third separation unit in sequence through pipelines.

9. The device according to claim 8, characterized in that The first depressurization separation unit and the second depressurization separation unit respectively include a depressurization device and a flash tank; and / or, The first separation unit is provided with a gas phase G2 outlet and a liquid phase L2 outlet, wherein the liquid phase L2 outlet is connected to the material inlet of the second pressure reduction separation unit through a pipeline; and / or, The first depressurization and separation unit is provided with a gas phase G3 outlet and a liquid phase L3 outlet, wherein the gas phase G3 outlet is connected to the second cooling unit and the second separation unit in sequence by a pipeline, and the liquid phase L3 outlet is connected to the material inlet of the second depressurization and separation unit by a pipeline; and / or, The second pressure reduction separation unit is provided with a gas phase G4 outlet and a liquid phase L4 outlet, wherein the gas phase G4 outlet is connected to the material inlet of the second cooling unit through a pipeline, and the liquid phase L4 outlet is connected to the material inlet of the third separation unit through a pipeline; and / or, The second separation unit is provided with a gas phase G5 outlet and a liquid phase L5 outlet, wherein the liquid phase L5 outlet is connected to the material inlet of the third separation unit through a pipeline; and / or, The third separation unit is provided with an outlet for a crude aldehyde product and an outlet for a mixture containing a hydroformylation catalyst and a solvent. Preferably, the outlet for the mixture containing a hydroformylation catalyst and a solvent is optionally provided with a pipeline connected to a hydroformylation reaction unit.

10. Use of the method for continuously treating a hydroformylation reaction product according to any one of claims 1 to 5 or the device for continuously treating a hydroformylation reaction product according to any one of claims 6 to 9 in treating a hydroformylation reaction product.

Images