Separation system, separation method and application of carbonyl synthesis catalyst and carbonyl synthesis product

Abstract

The invention provides a separation system and a separation method for a carbonyl synthesis catalyst and a carbonyl synthesis product, and application of the separation system and the separation method. According to the present invention, the separation of the carbonyl synthesis catalyst and the product is achieved only by using the conventional chemical equipment combination and adjusting the equipment height difference, such that the retention time of the catalyst solution in the high temperature region is minimum, and the condensation of the light component at the gas-liquid interface in the separation tank is less. 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 separation system and a separation method for carbonyl synthesis catalyst and carbonyl synthesis product and application thereof. Background Art

[0002] Carbonyl synthesis is an addition reaction between carbon monoxide and organic compounds under the catalysis of metal organic compounds to produce aldehydes, acids, esters, etc.

[0003] 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, phosphine ligands, phosphorene ligands, and oxalamide phosphorus ligands. The reaction conventionally adopts a homogeneous reaction, and olefins and CO are catalyzed by metal organic catalysts and ligands to insert carbonyl groups on the double bonds of olefins. 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. Ligands need to be added regularly, 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, affecting the continuous operation of the device.

[0004] In view of the above problems, conventional catalysts and products are separated by Figure 1a In the process shown, the reaction liquid (1') from carbonyl synthesis enters the evaporator (2'), where the reaction liquid is heated, wherein the light component (mainly the product) becomes a gas phase, and at the outlet of the evaporator (2'), a gas-liquid two-phase mixture is formed, and then enters the separation tank (3'), where the gas-liquid two-phase is separated, and the gas phase (4') (mainly the product) passes through the defoamer in the separation tank (3') and leaves the separation tank as a crude product. The liquid phase (mainly the catalyst) at the bottom of the separation tank is mainly the catalyst solution, which is cooled by the cooler inside the separation tank and returned to the reaction zone as the catalyst (5') solution for recycling. Because the cooling coil (6') in the separation tank has a limited coverage range, and the flow velocity of the fluid in the tank is low, the heat transfer is slow, resulting in a long residence time of the catalyst solution in the tank (the solution containing the catalyst and the ligand) at high temperature, resulting in a short ligand life and a large amount of ligand addition.

[0005] For conventional process 1a, the current industry also adopts Figure 1b The catalyst solution (5') at the bottom of the separation tank (3') is forced to circulate through a pump (9') at the bottom of the separation tank and cooled through an external cooler (6"), and then divided into two parts, one part of the catalyst solution (5'a) returns to the separation tank, and the other part of the catalyst solution (5'b) returns to the reaction system. Figure 1aCompared with the process shown in the figure, the residence time of the catalyst at low temperature is significantly shortened, but the high-temperature gas phase at the gas-liquid interface of the separation tank (3') contacts the cooled liquid phase and partially condenses, which reduces the amount of the gas phase and ultimately causes the evaporator (2') to require a larger heat load. Figure 1b The process adopts a forced circulation cooling solution and requires the use of a pump for forced condensation. The circulating pump has a large power and increases electricity consumption, resulting in increased energy consumption of the entire system. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a novel separation method of carbonyl synthesis catalyst and carbonyl synthesis product, which only adopts a conventional chemical equipment combination and adjusts the height difference of the equipment to achieve the separation of the carbonyl synthesis catalyst and the carbonyl synthesis product, so that the residence time of the catalyst solution in the high temperature area is minimized, and the light component condenses less at the gas-liquid interface in the separation tank; the method has the characteristics of low operating cost, simple equipment, small investment, easy operation and control, etc.

[0007] One of the objects of the present invention is to provide a separation system for carbonyl synthesis catalyst and carbonyl synthesis product, comprising: an evaporator, a cooler, a separation tank connected by pipelines, and optionally a receiving tank; wherein the highest point of the cooler is arranged below the operating liquid level of the separation tank.

[0008] According to the present invention, the evaporator is an evaporation separator, and the evaporator equipment commonly used in the art can be used to realize the gasification of the light component in the reaction liquid and realize gas-liquid separation at the lower end cap. The evaporator is provided with an upper end cap and a lower end cap, the top of the upper end cap of the evaporator is provided with an inlet for the material to be separated, the bottom of the lower end cap is provided with a liquid phase outlet, and the side wall of the lower end cap is provided with a gas phase outlet.

[0009] According to the present invention, the cooler may be a cooler device commonly used in the art, and the material inlet of the cooler is connected to the liquid phase outlet at the bottom of the evaporator by a pipeline.

[0010] According to the present invention, the top cover of the separation tank is provided with a gas phase external discharge pipeline; the side line of the separation tank is provided with a gas phase inlet, which is connected to the gas phase outlet of the evaporator by a pipeline; the side line of the separation tank below the gas phase inlet is provided with a liquid phase inlet, which is connected to the cooler outlet by a pipeline. A wire mesh demister is provided inside the separation tank near the top to reduce the amount of liquid phase entrained by the gas phase and reduce the entrainment loss of the catalyst and ligand.

[0011] According to the present invention, the separation system is optionally provided with a receiving tank, and the receiving tank can be a material receiving device commonly used in the art.

[0012] According to one embodiment of the present invention, the separation system includes an evaporator, a cooler, and a separation tank connected by pipelines, wherein the separation tank is divided into an upper section, a middle section, and a lower section from top to bottom, wherein the upper section of the separation tank is a cylindrical structure, the middle section is an inverted cone structure, and the lower section is a cylindrical structure with a reduced diameter; the upper end size of the inverted cone in the middle section is the same as the size of the upper section cylinder, and the lower end size is the same as the size of the lower section cylinder; a gas phase inlet is provided on the side line of the upper section of the separation tank, which is connected to the gas phase outlet provided on the side wall at the lower head of the evaporator by a pipeline; a liquid phase inlet is provided on the side line of the lower section of the separation tank, which is connected to the cooler outlet by a pipeline; a liquid phase discharge pipeline is provided at the bottom of the lower section of the separation tank.

[0013] In the above embodiment, in the separation tank, the ratio of the diameter of the lower cylinder to that of the upper cylinder is less than 1, preferably (0.2 to 0.3): 1; the gas phase inlet of the upper side line of the separation tank is arranged at 1 / 8 to 1 / 2 from the bottom to the top of the upper cylinder of the separation tank, preferably 1 / 4 to 1 / 3; the liquid phase inlet of the lower side line of the separation tank is arranged at 1 / 8 to 1 / 2 from the bottom to the top of the lower cylinder of the separation tank, preferably 1 / 8 to 1 / 4.

[0014] According to another embodiment of the present invention, the separation system also includes a receiving tank connected to a cooler by a pipeline, wherein the highest point of the cooler is arranged below the operating liquid level of the receiving tank; a liquid phase inlet is arranged on the side line of the receiving tank, which is connected to the cooler outlet by a pipeline; a liquid phase external discharge pipeline is arranged on the bottom of the receiving tank; a gas phase external discharge pipeline is arranged on the top cover of the receiving tank; the separation tank is a cylindrical structure; a gas phase inlet is arranged on the side line of the separation tank, which is connected to the gas phase outlet on the side wall of the lower head of the evaporator by a pipeline; a liquid phase outlet pipeline is arranged on the bottom of the separation tank, which is connected to the liquid phase outlet pipeline arranged on the bottom of the evaporator and connected to the cooler inlet.

[0015] In the above embodiment, the side line gas phase inlet of the separation tank is arranged at 1 / 10 to 3 / 4 of the separation tank from bottom to top, preferably 1 / 5 to 1 / 2; the side line liquid phase inlet of the receiving tank is arranged at 1 / 10 to 1 / 2 of the receiving tank from bottom to top, preferably 1 / 5 to 1 / 3; the gas phase external discharge pipeline of the separation tank top cover is connected to the gas phase external discharge pipeline arranged on the receiving tank top cover.

[0016] A second object of the present invention is to provide a method for separating a carbonyl synthesis catalyst from a carbonyl synthesis product, wherein the carbonyl synthesis catalyst and the carbonyl synthesis product are separated by using the above-mentioned separation system.

[0017] According to the present invention, the separation method comprises:

[0018] Method 1:

[0019] (1) The mixed liquid after the carbonyl synthesis reaction enters the evaporator, where the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, while the solution containing the catalyst is a liquid phase, and gas-liquid separation occurs at the lower head of the evaporator;

[0020] (2) After the gas-liquid separation in the evaporator, the gas phase enters the separation tank for further gas-liquid separation, and finally the gas phase is discharged and the liquid phase enters the bottom of the separation tank;

[0021] (3) The liquid phase after gas-liquid separation in the evaporator enters the cooler for cooling, and the cooled liquid phase enters the bottom of the separation tank, and then the catalyst solution is discharged from the bottom of the separation tank and returned to the reaction system;

[0022] or,

[0023] Method 2:

[0024] (1) The mixed liquid after the carbonyl synthesis reaction enters the evaporator, where the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, while the solution containing the catalyst is a liquid phase, and gas-liquid separation occurs at the lower head of the evaporator;

[0025] (2) After the gas-liquid separation in the evaporator, the gas phase enters the separation tank for another gas-liquid separation, and finally the gas phase is discharged, and the liquid phase enters the bottom of the separation tank and is connected to the liquid phase discharge pipeline of the evaporator through the pipeline and sent to the cooler together;

[0026] (3) The liquid phase after gas-liquid separation in the evaporator and the liquid phase at the bottom of the separation tank enter the cooler for cooling. The cooled liquid phase enters the bottom of the receiving tank, and then the catalyst solution is discharged from the bottom of the receiving tank and returned to the reaction system. The gas phase is discharged from the top of the receiving tank.

[0027] According to the present invention, in the separation method:

[0028] 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;

[0029] 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; and / or, the ligand is selected from an organic phosphorus ligand, preferably at least one of a triphenylphosphine ligand, a phosphate ligand, a phosphite ligand, a phosphophosphate ligand, a phosphorene ligand, and an oxalophosphine ligand;

[0030] 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 preferably at least one selected from ethylene, propylene, butene, pentene, hexene and octene.

[0031] According to the present invention, in the separation method, the operating conditions of the evaporator, cooler and separation tank 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.

[0032] A third object of the present invention is to provide a separation system for the carbonyl synthesis catalyst and the carbonyl synthesis product or a separation method for the carbonyl synthesis catalyst and the carbonyl synthesis product, and use the separation system in the carbonyl synthesis reaction.

[0033] The invention provides a method for separating a carbonyl synthesis catalyst and a product. The reaction liquid of the carbonyl synthesis enters an evaporator, and the product of the carbonyl synthesis is converted into a light component and evaporated into a gas phase in the evaporator. The catalyst solution is a liquid phase. Gas-liquid separation occurs at the lower head of the evaporator, and the gas phase enters a separation tank for gas-liquid separation again. Finally, the gas phase is discharged, and the liquid phase enters the bottom of the separation tank. The liquid phase (catalyst solution) at the lower head of the evaporator enters a cooler for cooling. The highest point of the cooler needs to be arranged below the operating liquid level under the separation tank to ensure that the catalyst solution always fills the cooler. The cooled catalyst solution enters the bottom of the separation tank, and then the catalyst solution is discharged and returned to the reaction system.

[0034] The present invention combines conventional chemical equipment evaporators, coolers and separation tanks, uses the lower end cap of the evaporator to perform the first gas-liquid separation, and the gas phase enters the separation tank for the second deep separation to reduce catalyst entrainment. The catalyst solution enters the pipe side of the cooler by its own gravity, and immediately enters the separation tank by the communicating vessel principle after being cooled. The bottom of the separation tank is reduced in diameter to reduce the contact between the gas and liquid surfaces or by adding a receiving tank, so as to finally achieve the separation of the carbonyl synthesis catalyst and the product. The technical scheme of the present invention is applicable to the separation of carbonyl synthesis catalysts, wherein the carbonyl synthesis reaction includes hydroformylation reaction, carbonyl esterification reaction, and carbonyl oxidation reaction.

[0035] In the separation system provided by the present invention, the reaction liquid of carbonyl synthesis is passed through the evaporator to obtain gas-liquid two-phases, and the gas-liquid two-phases are directly separated at the lower head of the evaporator. The liquid phase enters the cooler by gravity to cool, and then enters the lower section of the separation tank, so that the catalyst solution is cooled in the shortest time. At the same time, the catalyst solution flows by the height difference and the gravity of the fluid itself, which is energy-saving and convenient to control. At the same time, the cooler is arranged below the operating liquid level of the separation tank, and the liquid is always submerged in the heat exchanger, and the catalyst solution is always in a cooling state. If the position of the cooler is higher than the liquid level of the separation tank, the catalyst solution will pass through the cooler quickly, and the cooling time is not enough, and the cooling effect cannot be achieved well. The cooling effect is not enough, which affects the service life of the catalyst and the ligand. The separation system and method of the carbonyl synthesis catalyst of the present invention can realize the effective separation of the carbonyl synthesis catalyst and the product, and at the same time is conducive to protecting the life of the catalyst ligand and improving its recycling value, reducing the amount of catalyst addition, and the low energy consumption is conducive to industrial energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1a ~b is a schematic diagram of a separation device in the prior art.

[0037] Figure 2 This is a schematic diagram of the separation device used in Example 1, Figure 2 In the figure, 1-inlet for materials to be separated, 2-evaporator, 3-cooler, 4-separation tank, 5-gas phase external discharge pipeline of separation tank, 6-liquid phase outlet pipeline of separation tank, 7-upper head of evaporator, 8-lower head of evaporator, 9-gas phase outlet of evaporator side line, 10-gas phase inlet of separation tank side line, 11-liquid phase outlet of evaporator, 12-liquid phase inlet of separation tank side line, 13-wire mesh demister.

[0038] Figure 3 This is a schematic diagram of the separation device used in Example 2, Figure 3 In the figure, 1-inlet for materials to be separated, 2-evaporator, 3-cooler, 4-separation tank, 5-gas phase external discharge pipeline of separation tank, 6-liquid phase outlet pipeline of separation tank, 7-upper head of evaporator, 8-lower head of evaporator, 9-side gas phase outlet of evaporator, 10-side gas phase inlet of separation tank, 11-liquid phase outlet of evaporator, 13-wire mesh demister, 14-receiving tank, 15-liquid phase inlet of receiving tank, 16-gas phase outlet of receiving tank, 17-liquid phase outlet of receiving tank. DETAILED DESCRIPTION

[0039] 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.

[0040] Example 1

[0041] Combine the following Figure 2 The invention describes a separation system and a separation method for a carbonyl synthesis catalyst and a carbonyl synthesis product.

[0042] like Figure 2 As shown, the separation system of carbonyl synthesis catalyst and carbonyl synthesis product comprises: an evaporator 2, a cooler 3, and a separation 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 11, the upper head 7 and the lower head 8 are provided inside, and the gas phase pipeline outlet 9 is provided at the side wall of the lower head 8. The material inlet of the cooler 3 is connected to the liquid phase pipeline outlet 11 at the bottom of the evaporator by a pipeline, and the material outlet is connected to the liquid phase inlet 12 of the side line of the lower section of the separation tank by a pipeline. The top cover of the separation tank 4 is provided with a gas phase external discharge pipeline 5, and a wire mesh demister 13 is provided at the gas phase outlet. The highest point of the cooler 3 is set below the operating liquid level of the separation tank 4, and the separation tank 4 is divided into an upper section, a middle section and a lower section from top to bottom, wherein the upper section is a cylindrical structure, the middle section is an inverted cone structure, and the lower section is a cylindrical structure with a reduced diameter. A gas phase inlet 10 is arranged on the upper side line of the separation tank 4 and is connected to a gas phase pipeline outlet 9 of the evaporator by a pipeline; the upper end size of the middle inverted cone is the same as that of the upper cylinder, and the lower end size is the same as that of the lower cylinder; a liquid phase external discharge pipeline 6 is arranged at the bottom of the lower section of the separation tank 4.

[0043] Among them, the diameter of the lower cylinder of the separation tank is 1 / 4 of the diameter of the upper cylinder; the gas phase inlet 10 of the upper side line of the separation tank is set at 1 / 8 of the upper cylinder of the separation tank from bottom to top; the liquid phase inlet 12 of the lower side line of the separation tank is set at 1 / 8 of the lower cylinder of the separation tank from bottom to top.

[0044] Using the above Figure 2 A separation system is used to separate the carbonyl synthesis catalyst from the carbonyl synthesis product. The specific separation method includes:

[0045] (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 conditions for the carbonyl synthesis reaction are: reaction temperature 72°C, reaction pressure 1.2 MPaG.

[0046] (2) After the carbonyl reaction product passes through the evaporator 2, about 3 / 4 of the product is vaporized and enters the separation tank 4 through the gas phase outlet 9 of the lower head side line of the evaporator 2 for gas-liquid separation again. The separated gas phase is discharged and the liquid phase enters the bottom of the separation tank. The operating conditions of the evaporator are: the operating temperature of the evaporator is 90°C and the operating pressure is 0.08MPaG.

[0047] (3) The remaining 1 / 4 of the catalyst solution in the evaporator 2 has a temperature of about 90°C and enters the cooler 3 through the bottom pipe of the evaporator 2 and is cooled to 60°C. It then enters the bottom of the lower cylindrical structure of the separation tank 4. The catalyst obtained from the secondary gas-liquid separation in the separation tank is discharged from the bottom of the system and returned to the reaction system for recycling.

[0048] In the entire separation system, only a small section of catalyst solution with a temperature of 90°C is accumulated in the pipeline at the same height as the liquid level in the lower section of the separation tank in the inlet pipeline from the cooler to the cooler, 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 high-temperature section catalyst accounts for the smallest proportion. 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.

[0049] Example 2

[0050] Combine the following Figure 3 The invention describes a separation system and a separation method for a carbonyl synthesis catalyst and a carbonyl synthesis product.

[0051] like Figure 3 As shown, the separation system of the carbonyl synthesis catalyst and the carbonyl synthesis product includes: an evaporator 2, a cooler 3, a separation tank 4 and a receiving tank 14 connected by pipelines. The top of the evaporator 2 is provided with an inlet 1 for the material to be separated, the bottom is provided with a liquid phase pipeline outlet 11, the upper head 7 and the lower head 8 are provided inside, and the gas phase pipeline outlet 9 is provided at the side wall of the lower head 8. The material inlet of the cooler 3 is connected to the liquid phase pipeline outlet 11 at the bottom of the evaporator by a pipeline, and the material outlet is connected to the side line liquid phase inlet 15 of the receiving tank 14 by a pipeline. The top cover of the separation tank 4 is provided with a gas phase external discharge pipeline 5, a wire mesh demister 13 is provided at the gas phase outlet, and a gas phase inlet 10 is provided on the side line of the separation tank 4 and is connected to the gas phase pipeline outlet 9 of the evaporator 2 by a pipeline. The highest point of the cooler 3 is set below the operating liquid level of the separation tank 4 and the receiving tank 14. The separation tank 4 is a cylindrical structure. The liquid phase pipeline provided at the liquid phase outlet 6 at the bottom of the separation tank 4 is connected to the liquid phase outlet pipeline at the bottom of the evaporator 2, and is connected to the inlet of the cooler 3 by a pipeline. The bottom of the receiving tank 14 is provided with a liquid phase external discharge pipeline 17, and the top cover of the receiving tank 14 is provided with a gas phase external discharge pipeline 16, which is connected to the gas phase external discharge pipeline 5 on the top cover of the separation tank 4. Among them, the gas phase inlet 10 of the side line of the separation tank is set at 1 / 8 of the separation tank from bottom to top; the side line inlet 15 of the receiving tank is set at 1 / 4 of the receiving tank from bottom to top.

[0052] Using the above Figure 3 A separation system is used to separate the carbonyl synthesis catalyst from the carbonyl synthesis product. The specific separation method includes:

[0053] (1) Propylene and synthesis gas (hydrogen and carbon monoxide in a molar ratio of 1:1) undergo carbonyl synthesis reaction in the presence of rhodium acetylacetone catalyst and triphenylphosphine ligand to produce butyraldehyde, wherein the reaction temperature is 80°C and the reaction pressure is 1.35 MPaG.

[0054] (2) After the reaction product passes through the evaporator 2, about 3 / 4 of the product is vaporized and enters the separation tank 4 through the lower head side line of the evaporator 2 for gas-liquid separation again. The gas phase after the secondary separation in the separation tank is discharged, and the liquid phase enters the cooler 3. The operating conditions of the evaporator are as follows: the operating temperature of the evaporator is 100°C and the operating pressure is 0.08MPaG.

[0055] (3) The remaining 1 / 4 of the catalyst solution in the evaporator 2 has a temperature of about 100°C and enters the cooler 3 through the bottom pipe of the evaporator 2 and is cooled to 60°C. It then enters the receiving tank 14. The catalyst is discharged from the bottom of the receiving tank and returned to the reaction system for recycling.

[0056] In the entire separation system, only a small section of catalyst solution with a temperature of 100°C is accumulated in the pipeline from the cooler to the cooler inlet at the same height as the liquid level in the lower section of the receiving tank, 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 high-temperature section catalyst accounts for the smallest proportion. 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.

[0057] Comparative Example 1

[0058] Combine the following Figure 1a The present invention describes the separation method of carbonyl synthesis catalyst and carbonyl synthesis product used in the prior art.

[0059] The carbonyl reaction product (same as in Example 1) 1′ enters the evaporator 2′ to separate the catalyst and the product. The separated gas-liquid two phases enter the separation tank 3′ for gas-liquid two phase separation. The gas phase product 4′ is discharged from the top of the separation tank, and the catalyst solution enters the lower part of the separation tank 3′ to form a certain liquid level. The separation tank 3′ has a built-in cooler 6′. Figure 1a The part of the catalyst solution above the cooler has not been cooled, and the part below the cooler has been cooled. Conventionally, at least 1 / 3 of the catalyst solution has not been cooled and is in the high-temperature part, and 2 / 3 of the catalyst solution has been cooled and is in the low-temperature part. At the same time, due to the large diameter of the separation tank and the small liquid flow rate, the heat transfer coefficient is small when the catalyst solution contacts the cooler, and the cooling speed is slow.

[0060] Compared with Examples 1-2, in Comparative Example 1, the catalyst solution in the high temperature part accounts for more than 1 / 3 of the catalyst solution, while in Examples 1-2, the catalyst solution in the high temperature part accounts for only 1-2%. Examples 1-2 have obvious advantages in extending the service life of the catalyst and the ligand.

[0061] Comparative Example 2

[0062] Combine the following Figure 1b The present invention describes the separation method of carbonyl synthesis catalyst and carbonyl synthesis product used in the prior art.

[0063] The carbonyl reaction product (same as in Example 1) 1′ enters the evaporator 2′ to separate the catalyst and the product. The separated gas-liquid two-phase enters the separation tank 3′ for gas-liquid two-phase separation. The gas phase product 4′ is discharged from the top of the separation tank. The catalyst solution enters the lower part of the separation tank 3′ to form a certain liquid level. The catalyst solution 5′ is discharged from the separation tank 3′ and enters the catalyst pump 9′. The catalyst solution at the pump outlet enters the cooler 6′ for cooling. A part 5′b of the cooled catalyst returns to the reaction system, and a part 5′a returns to the separation tank 3′ to mix with the high-temperature catalyst from the evaporator 2′ for cooling.

[0064] Comparative Example 2 uses a catalyst pump. Since the reaction pressure of conventional carbonyl synthesis is greater than 1.0MPaG, the head of the catalyst pump is conventionally greater than 120m. Part of the catalyst solution returns to the separation tank, which consumes a lot of energy. At the same time, in order to cool the catalyst in the separation tank 3' in Comparative Example 2, it is conventional to ensure that the amount of 5'a is greater than 2-3 times the amount of catalyst entering the separation tank 3', resulting in a larger flow rate of the catalyst circulation amount 5'a and higher energy consumption. At the same time, due to the large diameter of the separation tank 3', the fluid mixing is prone to unevenness, forming a local high-temperature dead zone, causing the local catalyst to be at high temperature, affecting the life of the catalyst. At the same time, the upper and lower diameters of the separation tank 3' are the same, resulting in a large liquid surface area of ​​the catalyst solution. After contacting the gas phase space of the separation tank 3', the gas phase will be cooled at the liquid surface, causing the product to be cooled, resulting in high energy consumption. Compared with Examples 1 to 2, the process of Comparative Example 2 is complicated and requires more power consumption and energy consumption.

Claims

1. A separation system for an oxo synthesis catalyst and an oxo synthesis product, comprising: An evaporator, a cooler, and a separation tank connected by pipelines, and optionally a receiving tank; wherein the highest point of the cooler is arranged below the operating liquid level of the separation tank.

2. The separation system according to claim 1, characterized in that: The evaporator is provided with an upper head and a lower head, the top of the upper head of the evaporator is provided with an inlet for the material to be separated, the bottom of the lower head is provided with a liquid phase outlet, and the side wall of the lower head is provided with a gas phase outlet; and / or, The material inlet of the cooler is connected to the liquid phase outlet at the bottom of the evaporator by a pipeline; and / or, The top cover of the separation tank is provided with a gas phase discharge pipeline; and / or, The side line of the separation tank is provided with a gas phase inlet, which is connected to the gas phase outlet of the evaporator by a pipeline; and / or, The separation tank is provided with a liquid phase inlet at the side line below the gas phase inlet, which is connected to the cooler outlet by a pipeline; and / or, A wire mesh demister is arranged inside the upper section of the separation tank near the top.

3. The separation system according to claim 2, characterized in that: In the separation system, the separation tank is divided into an upper section, a middle section and a lower section from top to bottom; The upper section of the separation tank is a cylindrical structure, the middle section is an inverted cone structure, and the lower section is a cylindrical structure with a reduced diameter; A gas phase inlet is arranged on the upper side line of the separation tank, and is connected to a gas phase outlet arranged on the side wall of the lower end cap of the evaporator by a pipeline; A liquid phase inlet is provided on the lower side line of the separation tank and is connected to a cooler outlet by a pipeline; A liquid phase discharge pipeline is arranged at the bottom of the lower section of the separation tank.

4. The separation system according to claim 3, characterized in that: In the separation tank, the ratio of the diameter of the lower cylinder to that of the upper cylinder is less than 1, preferably (0.2-0.3):1; and / or, The gas phase inlet of the upper side line of the separation tank is arranged at 1 / 8 to 1 / 2, preferably 1 / 4 to 1 / 3 of the upper cylinder of the separation tank from bottom to top; and / or, The side line liquid phase inlet of the lower section of the separation tank is arranged at 1 / 8 to 1 / 2 of the lower section cylinder of the separation tank from bottom to top, preferably 1 / 8 to 1 / 4.

5. The separation system according to claim 2, characterized in that: The separation system also includes a receiving tank connected to the cooler by a pipeline; Wherein, the highest point of the cooler is arranged below the operating liquid level of the receiving tank; The receiving tank side line is provided with a liquid phase inlet, which is connected to the cooler outlet by a pipeline; A liquid phase discharge pipeline is arranged at the bottom of the receiving tank; The top cover of the receiving tank is provided with a gas phase external exhaust pipeline; The separation tank is a cylindrical structure; The separation tank side line is provided with a gas phase inlet, which is connected to the gas phase outlet on the side wall of the lower head of the evaporator by a pipeline; A liquid phase outlet pipeline is arranged at the bottom of the separation tank, which is communicated with the liquid phase outlet pipeline arranged at the bottom of the evaporator and connected to the inlet of the cooler.

6. The separation system according to claim 5, characterized in that The side gas phase inlet of the separation tank is arranged at 1 / 10 to 3 / 4, preferably 1 / 5 to 1 / 2, from bottom to top of the separation tank; and / or, The side line liquid phase inlet of the receiving tank is arranged at 1 / 10 to 1 / 2, preferably 1 / 5 to 1 / 3 of the bottom-up position of the receiving tank; and / or, The gas phase external discharge pipeline of the separation tank top cover is communicated with the gas phase external discharge pipeline provided on the receiving tank top cover.

7. A method for separating a carbonyl synthesis catalyst from a carbonyl synthesis product, comprising separating the carbonyl synthesis catalyst from the carbonyl synthesis product by using the separation system according to any one of claims 1 to 6.

8. The separation method according to claim 6, characterized in that The separation method comprises: Method 1: (1) The mixed liquid after the carbonyl synthesis reaction enters the evaporator, where the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, while the solution containing the catalyst is a liquid phase, and gas-liquid separation occurs at the lower head of the evaporator; (2) After the gas-liquid separation in the evaporator, the gas phase enters the separation tank for further gas-liquid separation, and finally the gas phase is discharged and the liquid phase enters the bottom of the separation tank; (3) The liquid phase after gas-liquid separation in the evaporator enters the cooler for cooling, and the cooled liquid phase enters the bottom of the separation tank, and then the catalyst solution is discharged from the bottom of the separation tank and returned to the reaction system; or, Method 2: (1) The mixed liquid after the carbonyl synthesis reaction enters the evaporator, where the carbonyl synthesis product becomes a light component and is evaporated into a gas phase, while the solution containing the catalyst is a liquid phase, and gas-liquid separation occurs at the lower head of the evaporator; (2) After the gas-liquid separation in the evaporator, the gas phase enters the separation tank for another gas-liquid separation, and finally the gas phase is discharged, and the liquid phase enters the bottom of the separation tank and is connected to the liquid phase discharge pipeline of the evaporator through the pipeline and sent to the cooler together; (3) The liquid phase after gas-liquid separation in the evaporator and the liquid phase at the bottom of the separation tank enter the cooler for cooling. The cooled liquid phase enters the bottom of the receiving tank, and then the catalyst solution is discharged from the bottom of the receiving tank and returned to the reaction system. The gas phase is discharged from the top of the receiving tank.

9. The separation 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 separation system for a carbonyl synthesis catalyst and a carbonyl synthesis product according to any one of claims 1 to 6 or a separation method for a carbonyl synthesis catalyst and a carbonyl synthesis product according to any one of claims 7 to 9 in a carbonyl synthesis reaction.

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