Recycling system, recycling method and application of carbonyl synthesis catalyst

Abstract

The invention provides a recovery system, a recovery method and application of a carbonyl synthesis catalyst. According to the invention, the variable-diameter evaporator is adopted, and the heights of the cooler and the receiving tank are adjusted, so that the carbonyl synthesis catalyst is separated from the product. The technical scheme provided by the invention has the characteristics of low operation cost, simple equipment, low investment, easiness in operation and control and the like.

Description

Technical Field

[0001] The invention belongs to the field of carbonyl synthesis, and in particular relates to a recovery system and a recovery method of a carbonyl synthesis catalyst and application thereof. Background Art

[0002] One of the methods for preparing organic compounds such as aldehydes, acids, and esters is to use carbonyl synthesis reaction. Conventionally, homogeneous reaction is used to insert carbonyl groups on the double bonds of olefins under the catalysis of metal organic catalysts and ligands to generate aldehydes, acids, esters, etc. The commonly used catalysts for carbonyl synthesis are rhodium, palladium, cobalt, platinum, copper, nickel, etc., and the commonly used ligands are organic phosphorus ligands, such as phosphate ligands, phosphite ligands, phosphophosphine ligands, phosphorene ligands, and oxalamide phosphorus ligands. Among them, metal organic catalysts and phosphorus ligands are sensitive to temperature changes and are easily decomposed at high temperatures, resulting in a decrease in reaction rate. It is necessary to regularly add ligands, which increases operating costs. At the same time, when the degraded ligands accumulate to a certain concentration, they need to be discharged regularly, resulting in the need for regular unloading and regeneration of the catalyst, which affects the continuous operation of the device.

[0003] Patent CN107141204B relates to a hydroformylation process and discloses an improved method for separating a catalyst from a product, wherein a partition is provided at the gas-liquid contact interface of a separation tank, wherein at least one partition selectively contains at least one perforation, wherein at least a portion of at least one partition is near the gas-liquid interface, provided that at least a portion of at least one partition is at or below the interface, and wherein the temperature of the liquid containing the catalyst measured at the liquid extraction port is lower than the temperature of the vapor space. The partition of this invention can isolate the gas-liquid interface and prevent the light components in the separation tank from condensing at the gas-liquid interface. However, the built-in cooler of the separation tank is a built-in heat exchanger, which only has a tube bundle but no shell side and shell side fluid guide plates, resulting in low heat exchange efficiency of the catalyst solution in the shell side, poor heat exchange effect of the cooler, large volume, and too long residence time of the catalyst outside the cooler tube bundle. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a carbonyl synthesis catalyst recovery system, recovery method and application. In the present invention, only conventional chemical equipment combinations, such as evaporators, coolers and receiving tanks, are used to adjust the height difference of the equipment to achieve the separation of carbonyl synthesis catalyst and product.

[0005] One of the purposes of the present invention is to provide a carbonyl synthesis catalyst recovery system, comprising: an evaporator, a cooler, and a receiving tank connected in sequence by pipelines, wherein the operating liquid level of the receiving tank is higher than the highest point of the cooler.

[0006] According to the present invention, in the recovery system of the oxo synthesis catalyst:

[0007] The evaporator is an evaporation separator, and the evaporator equipment commonly used in the art can be used to achieve the gasification of the light components in the reaction liquid. Preferably, the top of the upper head of the evaporator is provided with an inlet for the material to be separated;

[0008] A liquid phase outlet is provided at the bottom of the lower head of the evaporator and is connected to a liquid phase inlet of the cooler by a pipeline;

[0009] The evaporator is a cylindrical tank body, provided with an upper head and a lower head; wherein the lower head includes a tank body with a large diameter near the bottom end and a tank body with a small diameter above the bottom end, and the connection between the two parts of the tank body can adopt a common reducer connection method in the art;

[0010] Preferably, in the evaporator, the ratio of the diameter of the large-diameter tank body near the bottom end of the lower head to the small-diameter tank body above the lower head is greater than 1, preferably (1.5-3):1;

[0011] In the evaporator, a gas phase external discharge outlet is arranged at the side wall of the large-diameter tank body near the bottom of the lower head, and specifically, the gas phase external discharge outlet is arranged at 1 / 8 to 7 / 8, preferably 1 / 4 to 1 / 2, of the side wall of the large-diameter tank body near the bottom of the lower head from top to bottom; a baffle and a wire mesh demister are arranged inside the gas phase external discharge outlet of the lower head of the evaporator, the baffle is arranged above the wire mesh demister, and the baffle and the wire mesh demister are both arranged horizontally and fixed to the inner wall of the evaporator;

[0012] The lower evaporator head has a small-diameter tank body, the diameter of which is consistent with the diameter of the evaporator tank body above it.

[0013] According to the present invention, in the recovery system of the oxo synthesis catalyst:

[0014] The cooler can adopt a cooler device commonly used in the art. Specifically, the cooler is provided with a liquid phase inlet and a liquid phase outlet. The liquid phase inlet is connected to the liquid phase outlet at the bottom of the evaporator by a pipeline, and the liquid phase outlet is connected to the liquid phase inlet of the receiving tank by a pipeline.

[0015] According to the present invention, in the recovery system of the oxo synthesis catalyst:

[0016] The receiving tank can adopt a material receiving device commonly used in the art. Specifically, the receiving tank has a liquid phase inlet on the side line, a gas phase outlet on the top, and a liquid phase outlet on the bottom. Preferably, the liquid phase inlet on the side line of the receiving tank is arranged at 1 / 10 to 3 / 4, preferably 1 / 5 to 1 / 2, from the bottom to the top of the receiving tank; the gas phase outlet pipeline on the top of the receiving tank is connected to the gas phase outlet pipeline arranged on the side wall of the large diameter tank body near the bottom of the lower head of the evaporator;

[0017] The gas phase of the receiving tank is connected to the gas phase of the side wall of the lower head of the evaporator, which is the gas phase equilibrium line to balance the pressure. The receiving tank is used to receive the catalyst and form a gas-liquid interface inside the receiving tank. Because the catalyst solution in the receiving tank has been cooled by the cooler and the temperature is relatively low, part of the gas phase will be cooled by contact with the liquid surface. Since the size of the gas phase equilibrium line pipeline is relatively small, a very small amount of gas is cooled in the receiving tank.

[0018] A second object of the present invention is to provide a method for recovering the carbonyl synthesis catalyst, wherein the carbonyl synthesis catalyst is recovered in the above-mentioned recovery system.

[0019] According to the present invention, the recovery method comprises:

[0020] (1) the mixed liquid after carbonyl synthesis enters the evaporator, in which the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, the catalyst solution is a liquid phase, and gas-liquid separation occurs at the lower end of the evaporator;

[0021] (2) After the gas-liquid separation in the evaporator, the gas phase is discharged, and the liquid phase enters the cooler for cooling and is then sent to the receiving tank;

[0022] (3) The cooled liquid phase enters a receiving tank, where it is further cooled. The catalyst solution is discharged from the bottom of the receiving tank and returned to the reaction system for recycling.

[0023] According to the present invention, in the recovery method:

[0024] The carbonyl synthesis reaction is not particularly limited and can be a commonly used carbonyl synthesis reaction, for example, the carbonyl synthesis is at least one of a hydroformylation reaction, a carbonyl esterification reaction, and a carbonyl oxidation reaction;

[0025] The catalyst is not particularly limited and can be a catalyst commonly used in carbonyl synthesis reactions. For example, the catalyst is a metal ligand compound. Preferably, the metal is selected from at least one of rhodium, palladium, cobalt, platinum, copper and nickel; the ligand is selected from organophosphorus ligands, preferably at least one of phosphate ligands, phosphite ligands, phosphophosphine ligands, phosphorene ligands and oxalophosphine ligands;

[0026] The raw material for carbonyl synthesis is an olefin compound, wherein the olefin compound can be an olefin compound commonly used in carbonyl synthesis in the art. For example, the raw material for carbonyl synthesis is an olefin compound, preferably at least one selected from ethylene, propylene, butene, pentene, hexene, and octene.

[0027] According to the present invention, in the recovery method, the operating conditions of the evaporator and the cooler can select suitable operating temperature and operating pressure according to the product obtained from the specific carbonyl synthesis reaction and the catalyst used. For example, the operating temperature of the evaporator can be selected within the range of 65 to 140°C, the operating conditions of the receiving tank are the same as those of the evaporator, and the outlet temperature of the cooler can be controlled to be no higher than 60°C.

[0028] A third object of the present invention is to provide a system for recovering the carbonyl synthesis catalyst or a method for recovering the carbonyl synthesis catalyst, and use the system or method in a carbonyl synthesis reaction.

[0029] The invention provides a method for recovering a carbonyl synthesis catalyst. The conventional chemical equipment evaporator, cooler and receiving tank are combined. The reaction liquid of the carbonyl synthesis enters the evaporator. In the evaporator, the product of the carbonyl synthesis becomes a light component and is evaporated into a gas phase. The catalyst solution is a liquid phase. Gas-liquid separation occurs in the lower section of the evaporator. The separated gas phase is discharged through a wire mesh demister. The liquid phase (catalyst solution) enters the pipe side of the cooler by its own gravity and enters the cooler for cooling. The highest point of the cooler needs to be arranged below the operating liquid level under the receiving tank to ensure that the catalyst solution always fills the cooler. The cooled catalyst solution enters the bottom of the receiving tank by the principle of a communicating vessel, and then the catalyst solution is discharged and returned to the reaction system for recycling.

[0030] The present invention adopts an evaporator lower head including cylindrical tank bodies of different diameters. The lower head includes a tank body with a large diameter near the bottom end and a tank body with a small diameter above the bottom end. The above design is conducive to gas-liquid separation. The diameter of the lower cylindrical tank body becomes larger, the gas phase flow rate becomes smaller, and the liquid entrained by the gas phase becomes smaller, which is more conducive to gas-liquid separation and improves the separation efficiency.

[0031] The technical solution provided by the present invention has the following beneficial effects:

[0032] (1) Low operating cost. The catalyst solution flows only by gravity and is cooled by a cooler. The catalyst solution in the high temperature section is small, which has a significant effect on extending the life of the catalyst and ligand.

[0033] (2) The equipment is simple. The gas-liquid separation is carried out by expanding the diameter of the lower section of the evaporator. The purpose of catalyst separation and cooling is achieved by combining several simple typical equipment. The equipment is simple and easy to implement in engineering.

[0034] (3) Small investment, because the equipment is simple and all are conventional typical equipment;

[0035] (4) Easy to control, because the catalyst solution flows by its own gravity, no control is required, and it can flow and be cooled as long as the height difference requirements are met. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the carbonyl synthesis catalyst recovery system used in Examples 1 and 2 of the present invention.

[0037] Figure 1 In the figure, 1-inlet for materials to be separated, 2-evaporator, 3-cooler, 4-receiving tank, 5-upper head of evaporator, 6-lower head of evaporator, 7-gas phase outlet of evaporator side line, 8-liquid phase outlet of evaporator, 9-liquid phase inlet of receiving tank side line, 10-gas phase external discharge pipeline of receiving tank, 11-liquid phase external discharge pipeline of separation tank, 12-wire mesh demister. DETAILED DESCRIPTION

[0038] The invention provides a method for recovering a carbonyl synthesis catalyst. The conventional chemical equipment evaporator, cooler and receiving tank are combined. The reaction liquid of the carbonyl synthesis enters the evaporator. In the evaporator, the product of the carbonyl synthesis becomes a light component and is evaporated into a gas phase. The catalyst solution is a liquid phase. Gas-liquid separation occurs in the lower section of the evaporator. The separated gas phase is discharged through a wire mesh demister. The liquid phase (catalyst solution) enters the pipe side of the cooler by its own gravity and enters the cooler for cooling. The highest point of the cooler needs to be arranged below the operating liquid level under the receiving tank to ensure that the catalyst solution always fills the cooler. The cooled catalyst solution enters the bottom of the receiving tank by the principle of a communicating vessel, and then the catalyst solution is discharged and returned to the reaction system for recycling.

[0039] To achieve the above object, the present invention provides a carbonyl synthesis catalyst recovery system, comprising: an evaporator, a cooler, and a receiving tank connected by pipelines, wherein the operating liquid level of the receiving tank is higher than the highest point of the cooler.

[0040] Wherein, in the recovery system of the carbonyl synthesis catalyst:

[0041] An inlet for materials to be separated is arranged at the top of the upper head of the evaporator;

[0042] A liquid phase outlet is provided at the bottom of the lower head of the evaporator and is connected to a liquid phase inlet of the cooler by a pipeline;

[0043] The evaporator is a cylindrical tank body, which is provided with an upper head and a lower head. The lower head includes a tank body with a large diameter near the bottom end and a tank body with a small diameter above the part. The connection method between the two parts of the tank body can adopt a reducer connection method commonly used in the art; wherein, the diameter ratio of the tank body with a large diameter near the bottom end of the lower head and the tank body with a small diameter above the part is greater than 1, preferably (1.5-3):1; a gas phase external discharge outlet is arranged at the side wall of the tank body with a large diameter near the bottom end of the lower head, and a wire mesh demister is optionally arranged at the gas phase external discharge outlet; preferably, the gas phase external discharge outlet is arranged at 1 / 8-7 / 8 of the side wall of the tank body with a large diameter near the bottom end of the lower head from top to bottom, preferably 1 / 4-1 / 2.

[0044] In the recovery system of the oxo synthesis catalyst:

[0045] The cooler is provided with a liquid phase inlet and a liquid phase outlet. The liquid phase inlet is connected to the liquid phase outlet at the bottom of the evaporator by a pipeline, and the liquid phase outlet is connected to the liquid phase inlet of the side line of the receiving tank by a pipeline.

[0046] In the recovery system of the oxo synthesis catalyst:

[0047] The receiving tank side line is provided with a liquid phase inlet, the top is provided with a gas phase external discharge outlet, and the bottom is provided with a liquid phase external discharge outlet. Preferably, the receiving tank side line liquid phase inlet is arranged at 1 / 10 to 3 / 4 of the receiving tank from bottom to top, preferably 1 / 5 to 1 / 2; the gas phase external discharge outlet pipeline at the top of the receiving tank is communicated with the gas phase external discharge outlet pipeline arranged on the side wall of the tank body with a large diameter near the bottom end of the lower head of the evaporator.

[0048] The present invention provides a method for recovering an oxo synthesis catalyst, comprising:

[0049] (1) The mixed liquid after carbonyl synthesis enters the evaporator, where the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, while the catalyst solution is a liquid phase, and gas-liquid separation occurs at the lower head of the evaporator;

[0050] (2) After the gas-liquid separation in the evaporator, the gas phase is discharged, and the liquid phase enters the cooler for cooling and is then sent to the receiving tank;

[0051] (3) The cooled liquid phase enters a receiving tank, where it is further cooled. The catalyst solution is discharged from the bottom of the receiving tank and returned to the reaction system for recycling.

[0052] Wherein, the carbonyl synthesis is at least one of a hydroformylation reaction, a carbonyl esterification reaction, and a carbonyl oxidation reaction;

[0053] The catalyst is a metal ligand compound, preferably, the metal is selected from at least one of rhodium, palladium, cobalt, platinum, copper and nickel; the ligand is selected from organic phosphorus ligands, preferably at least one of triphenylphosphine ligands, phosphate ligands, phosphite ligands, phosphine phosphate ligands, phosphorene ligands and oxalamide phosphorus ligands;

[0054] The raw material for carbonyl synthesis is an olefin compound, preferably at least one selected from ethylene, propylene, butene, pentene, hexene and octene;

[0055] The operating temperature of the evaporator can be selected within the range of 65 to 140°C, the operating conditions of the receiving tank are the same as those of the evaporator, and the outlet temperature of the cooler can be controlled to be no higher than 60°C.

[0056] The present invention is described in detail below in conjunction with specific embodiments. 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 contents of the present invention still fall within the scope of protection of the present invention.

[0057] Example 1

[0058] Combine the following Figure 1 The invention describes a recovery system and a recovery method for the carbonyl synthesis catalyst.

[0059] like Figure 1 As shown, the recovery system of carbonyl synthesis catalyst includes: an evaporator 2, a cooler 3, and a receiving tank 4 connected by pipelines, wherein the top of the evaporator 2 is provided with a material inlet 1 to be separated, the bottom is provided with a liquid phase pipeline outlet 8, the upper head 5 and the lower head 6 are provided inside, the side wall of the lower cylindrical tank body is provided with a gas phase pipeline outlet 7, and a wire mesh demister 12 is provided at the gas phase pipeline outlet 7. The material inlet of the cooler 3 is connected to the liquid phase pipeline outlet 8 at the bottom of the evaporator by a pipeline, and the material outlet is connected to the side line liquid phase inlet 9 of the receiving tank by a pipeline. The top cover of the receiving tank 4 is provided with a gas phase external discharge pipeline 10, and the highest point of the cooler 3 is set below the operating liquid level of the receiving tank 4.

[0060] In the recovery system adopted, the ratio of the diameter of the tank body with a large diameter near the bottom end of the lower head of the evaporator 2 to the tank body with a small diameter above this part is 2:1, the gas phase external discharge outlet is arranged at 1 / 4 of the side wall of the tank body with a large diameter near the bottom end of the lower head from top to bottom, and the receiving tank side line liquid phase inlet 9 is arranged at 1 / 4 of the receiving tank 4 from bottom to top.

[0061] Using the above Figure 1 The recovery system is used to recover the carbonyl synthesis catalyst. The specific recovery method includes:

[0062] (1) Ethylene and synthesis gas (hydrogen and carbon monoxide in a molar ratio of 1:1) undergo carbonyl synthesis reaction in the presence of rhodium acetate catalyst and triphenylphosphine ligand to produce propionaldehyde, wherein the temperature of the carbonyl synthesis reaction is 72°C and the reaction pressure is 1.2 MPaG.

[0063] (2) After the reaction product passes through the evaporator 2, about 3 / 4 of the product is vaporized and enters the lower head 6 of the evaporator. The gas-liquid separation is carried out in the lower head. The gas phase passes through the wire mesh demister 12 and then is discharged from the evaporator. The liquid phase 8 at a temperature of 90°C enters the cooler 3 by its own gravity for cooling. After cooling to 60°C, it flows into the receiving tank 4 by gravity. The gas phase 10 of the receiving tank 4 is connected to the gas phase 7 from the evaporator. The catalyst solution 11 at the bottom of the receiving tank is discharged from the system. Among them, the operating temperature of the evaporator is 90°C and the operating pressure is 0.08MPaG.

[0064] In the entire separation system, only a small section of catalyst solution with a temperature of 90°C is accumulated in the pipe at the same height as the liquid level in the receiving tank in the outlet pipeline at the bottom of the cooler and the lower head of the evaporator, which accounts for about 1-2% of the volume of the catalyst solution. The temperature of the remaining catalyst is lower than 60°C. The proportion of the catalyst in the high-temperature part is very small. The low temperature is very beneficial to the life of the catalyst and the stability of the ligand, which can extend the amount of catalyst and ligand added to the device and extend the long-term operation time of the device.

[0065] Example 2

[0066] Combine the following Figure 1 The invention describes a recovery system and a recovery method for the carbonyl synthesis catalyst.

[0067] like Figure 1 As shown, the recovery system of carbonyl synthesis catalyst includes: an evaporator 2, a cooler 3, and a receiving tank 4 connected by pipelines, wherein the top of the evaporator 2 is provided with a material inlet 1 to be separated, the bottom is provided with a liquid phase pipeline outlet 8, the upper head 5 and the lower head 6 are provided inside, the side wall of the lower cylindrical tank body is provided with a gas phase pipeline outlet 7, and a wire mesh demister 12 is provided at the gas phase pipeline outlet 7. The material inlet of the cooler 3 is connected to the liquid phase pipeline outlet 8 at the bottom of the evaporator by a pipeline, and the material outlet is connected to the side line liquid phase inlet 9 of the receiving tank by a pipeline. The top cover of the receiving tank 4 is provided with a gas phase external discharge pipeline 10, and the highest point of the cooler 3 is set below the operating liquid level of the receiving tank 4.

[0068] In the recovery system adopted, the ratio of the diameter of the tank body with a large diameter near the bottom end of the lower head of the evaporator 2 to the tank body with a small diameter above this part is 4:1, the gas phase external discharge outlet is arranged at 1 / 2 from top to bottom of the side wall of the tank body with a large diameter near the bottom end of the lower head, and the receiving tank side line liquid phase inlet 9 is arranged at 1 / 4 from bottom to top of the receiving tank 4.

[0069] Using the above Figure 1 The recovery system is used to recover the carbonyl synthesis catalyst. The specific recovery method includes:

[0070] (1) 1-Butene and synthesis gas (hydrogen and carbon monoxide in a molar ratio of 1:1) undergo carbonyl synthesis reaction in the presence of rhodium acetate catalyst and phosphite ligand to produce propionaldehyde, wherein the temperature of the carbonyl synthesis reaction is 82°C and the reaction pressure is 1.3 MPaG.

[0071] (2) After the reaction product passes through the evaporator 2, about 90% of the reaction liquid is vaporized and enters the lower head 6 of the evaporator. The gas-liquid separation is carried out in the lower head. The gas phase passes through the wire mesh demister 12 and then is discharged from the evaporator. The liquid phase 8 with a temperature of 105°C enters the cooler 3 by its own gravity for cooling. After cooling to 60°C, it flows into the receiving tank 4 by gravity. The gas phase 10 of the receiving tank 4 is connected to the gas phase 7 from the evaporator. The catalyst solution 11 at the bottom of the receiving tank is discharged from the system. Among them, the operating temperature of the evaporator is 105°C and the operating pressure is 0.04MPaG.

[0072] In the entire separation system, only a small section of catalyst solution with a temperature of 120°C is accumulated in the pipe at the same height as the liquid level in the receiving tank in the outlet pipeline at the bottom of the cooler and the lower head of the evaporator, which accounts for about 1-2% of the volume of the catalyst solution. The temperature of the remaining catalyst is lower than 60°C. The proportion of the catalyst in the high-temperature part is very small. The low temperature is very beneficial to the life of the catalyst and the stability of the ligand, which can extend the amount of catalyst and ligand added to the device and extend the long-term operation time of the device.

[0073] Comparative Example 1

[0074] A separation device according to the prior art (see FIG2 of patent CN107141204B) is used as comparative example 1.

[0075] The carbonyl reaction product (same as Example 1) enters the evaporator to separate the catalyst and the product. The separated gas-liquid two-phase enters the separation tank for gas-liquid two-phase separation. The gas phase product is discharged from the top of the separation tank, and the catalyst solution enters the lower part of the separation tank to form a certain liquid level. The separation tank has a built-in cooler. The catalyst solution above the cooler accounts for about 30% of the catalyst solution, that is, the catalyst solution in the high temperature section accounts for more than 30%. In Comparative Example 1, the built-in cooler is built in the separation tank, so the flow rate of the catalyst solution is small and the cooling effect is poor.

[0076] Compared with comparative example 1, the catalyst solution in the high temperature section in example 1 only accounts for 1-2%. The catalyst has a good cooling effect and a longer service life. In addition, the present invention combines the separation tank with the evaporator, and uses the lower head of the evaporator for separation, which reduces the equipment investment; the cooler is simpler, the catalyst solution enters the cooler through a pipeline, the heat transfer coefficient of the catalyst solution in the cooler is high, and the cooling effect is good.

Claims

1. A recovery system for an oxo synthesis catalyst, comprising: An evaporator, a cooler, and a receiving tank are connected in sequence by pipelines, wherein the operating liquid level of the receiving tank is higher than the highest point of the cooler.

2. The recovery system according to claim 1, characterized in that: The top of the upper end cover of the evaporator is provided with an inlet for the material to be separated; and / or, A liquid phase outlet is arranged at the bottom of the lower head of the evaporator and is connected to a liquid phase inlet of the cooler by a pipeline.

3. The recovery system according to claim 1, characterized in that: The evaporator is a cylindrical tank body, provided with an upper head and a lower head, wherein the lower head comprises a tank body with a large diameter near the bottom end and a tank body with a small diameter above the bottom end.

4. The recovery system according to claim 3, characterized in that: In the evaporator, the ratio of the diameter of the large-diameter tank body near the bottom end of the lower head to the small-diameter tank body above the lower head is greater than 1, preferably (1.5-3):1; and / or, In the evaporator, a gas phase discharge outlet is arranged at the side wall of the tank body with a large diameter near the bottom end of the lower head; preferably, the gas phase discharge outlet is arranged at 1 / 8 to 7 / 8, preferably 1 / 4 to 1 / 2, of the side wall of the tank body with a large diameter near the bottom end of the lower head; and / or, The lower evaporator head has a small-diameter tank body, the diameter of which is consistent with the diameter of the evaporator tank body above it.

5. The recovery system according to claim 1, characterized in that: The cooler is provided with a liquid phase inlet and a liquid phase outlet, the liquid phase inlet is connected to the liquid phase outlet at the bottom of the evaporator by a pipeline, and the liquid phase outlet is connected to the liquid phase inlet of the receiving tank by a pipeline; and / or, The receiving tank is provided with a liquid phase inlet on the side line, a gas phase outlet on the top, and a liquid phase outlet on the bottom.

6. The recovery system according to claim 5, characterized in that: The side line liquid phase inlet of the receiving tank is arranged at 1 / 10 to 3 / 4, preferably 1 / 5 to 1 / 2, from bottom to top of the receiving tank; and / or, The gas phase external discharge outlet pipeline at the top of the receiving tank is communicated with the gas phase external discharge outlet pipeline arranged on the side wall of the tank body with a large diameter near the bottom end of the lower head of the evaporator; and / or, A baffle and a wire mesh demister are arranged inside the gas phase external discharge outlet of the lower head of the evaporator.

7. A method for recovering a carbonyl synthesis catalyst, comprising recovering the carbonyl synthesis catalyst by using the recovery system according to any one of claims 1 to 6.

8. The recycling method according to claim 7, characterized in that: The recycling method comprises: (1) the mixed liquid after carbonyl synthesis enters the evaporator, in which the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, the catalyst solution is a liquid phase, and gas-liquid separation occurs at the lower end of the evaporator; (2) After the gas-liquid separation in the evaporator, the gas phase is discharged, and the liquid phase enters the cooler for cooling and is then sent to the receiving tank; (3) The cooled liquid phase enters a receiving tank, where it is further cooled. The catalyst solution is discharged from the bottom of the receiving tank and returned to the reaction system for recycling.

9. The recycling method according to claim 8, characterized in that: The carbonylation reaction is at least one of a hydroformylation reaction, a carbonyl esterification reaction, and a carbonyl oxidation reaction; and / or, The catalyst is a metal ligand compound, preferably, the metal is selected from at least one of rhodium, palladium, cobalt, platinum, copper and nickel; and / or, the ligand is selected from organic phosphorus ligands, preferably at least one of triphenylphosphine ligands, phosphate ligands, phosphite ligands, phosphine phosphate ligands, phosphorene ligands and oxalamide phosphorus ligands; and / or, The raw material for carbonyl synthesis is an olefin compound, preferably at least one selected from ethylene, propylene, butene, pentene, hexene and octene.

10. Use of a system for recovering a carbonyl synthesis catalyst according to any one of claims 1 to 6 or a method for recovering a carbonyl synthesis catalyst according to any one of claims 7 to 9 in a carbonyl synthesis reaction.

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