A system and method for separating 1-hexene from an ethylene trimer product

Abstract

The application discloses a system and a method for separating 1-hexene in ethylene trimerization products, and the system comprises a light-removing column which is provided with a top outlet and a column bottom outlet; a dividing wall column which is connected with the column bottom outlet of the light-removing column, wherein the top of the dividing wall column is provided with a light component outlet, the column bottom is provided with a heavy component outlet, and a side line is provided with a solvent outlet; and a purification column which is connected with the light component outlet of the dividing wall column, wherein the top of the purification column is provided with a butene outlet, and the column bottom is provided with a product outlet; and wherein a heat exchange device is further arranged between the solvent outlet and the heavy component outlet of the dividing wall column, so that the solvent component flowing out of the solvent outlet is subjected to heat exchange with the heavy component flowing out of the heavy component outlet, the heat-exchanged heavy component returns to the bottom of the dividing wall column, and the heat-exchanged solvent component partially returns to the dividing wall column. The system has low energy consumption.

Description

Technical Field

[0001] This invention belongs to the field of chemical distillation, and in particular relates to a system for separating 1-hexene from ethylene trimer products, and a method for separating 1-hexene from ethylene trimer products. Background Technology

[0002] 1-Hexene is an organic compound mainly used in the manufacture of fragrances, dyes and synthetic resins.

[0003] Traditional processes for separating 1-hexene from ethylene trimer products, such as Figure 1 As shown, the ethylene trimer product SO1 is fed into the light component removal tower C2-T. The resulting liquid stream SO2 from the bottom of the tower is directly fed into the decene recovery tower C10-T. All the solvent is vaporized in the decene recovery tower C10-T. The solvent discharged from the top of the decene recovery tower is then condensed and enters the solvent recovery tower C6-T. The solvent is discharged from the bottom of the solvent recovery tower C6-T and separated. The gaseous product SO4 is separated from the top of the solvent recovery tower C6-T and enters the purification tower C4-T. Light component by-products are obtained at the top of the tower, and hexene is obtained from the bottom of the tower.

[0004] Therefore, traditional methods require at least two distillation columns for solvent recovery and reuse. The concentration of intermediate components, i.e., solvent, tends to peak within the column, which can lead to backmixing of intermediate components, thereby reducing separation efficiency and increasing energy consumption.

[0005] CN1609083A employs two distillation columns connected in series to purify 1-hexene. The process utilizes a side-stream discharge column, simultaneously completing the removal of heavy and light components within a single column, reducing production costs and equipment investment compared to the traditional three-column series method. However, this patent does not significantly reduce energy consumption, achieving only about 7%.

[0006] CN113166001A addresses the issue of low-molecular-weight polyethylene (LAO) products obtained in the presence of Ziegler-type catalysts, which typically require multiple distillation columns to separate the linear α-olefin (LAO) product to the desired carbon number. However, multiple distillation columns lead to energy and capital intensity problems. A proposal suggests using at least one partition wall column to separate the LAO product to reduce these burdens. However, this method requires at least one reboiler and one condenser in the partition wall column, and the heat from the top and bottom of the column cannot be effectively utilized.

[0007] Therefore, further research is needed in this field on methods for separating 1-hexene from ethylene trimer products. Summary of the Invention

[0008] The main objective of this invention is to provide a system and method for separating 1-hexene from ethylene trimer products, so as to overcome the problems of multiple distillation columns, low separation efficiency, and high energy consumption in the prior art when separating 1-hexene from ethylene trimer products.

[0009] To achieve the above objectives, the present invention provides a system for separating 1-hexene from ethylene trimer products, comprising:

[0010] The light-weight removal tower is equipped with a top outlet and a bottom outlet.

[0011] The partition wall column is connected to the bottom outlet of the light component removal column. The top of the partition wall column is provided with a light component outlet, the bottom of the column is provided with a heavy component outlet, and the side line is provided with a solvent outlet and a solvent component inlet.

[0012] A purification tower is connected to the light component outlet of the partition tower. The top of the purification tower is provided with a butene outlet, and the bottom of the tower is provided with a 1-hexene product outlet.

[0013] A heat exchange device is provided between the solvent outlet and the heavy component outlet of the partition tower, so that the solvent component flowing out of the solvent outlet and the heavy component flowing out of the heavy component outlet can exchange heat. The heavy component after heat exchange returns to the bottom of the partition tower, and part of the solvent component after heat exchange returns to the partition tower.

[0014] The system for separating 1-hexene from ethylene trimer products according to the present invention includes a pressurizing device between the solvent outlet of the partition tower and the heat exchange device, so that the solvent component flowing out of the solvent outlet is pressurized and heated before entering the heat exchange device.

[0015] The system for separating 1-hexene from ethylene trimer products according to the present invention includes an inlet on the side of the light trimer, through which the ethylene trimer products enter the light trimer.

[0016] The system for separating 1-hexene from ethylene trimer products according to the present invention includes a partition wall in which a partition plate is provided to divide the partition wall into a pre-separation tower and a main tower, and the solvent component after heat exchange is partially returned to the main tower.

[0017] The system for separating 1-hexene from ethylene trimer products according to the present invention comprises a pre-separation tower with 20-36 theoretical plates, a main tower with 30-66 theoretical plates, and a partition tower with a reflux ratio of 10-12.

[0018] The system for separating 1-hexene from ethylene trimer products according to the present invention includes a feed inlet in the partition column located on trays 5-14 of the pre-separation column, a solvent outlet in the main column located on trays 30-50, a solvent component inlet in the main column located on the tray above the solvent outlet, an upper end of the partition plate located on trays 10-20, and a lower end of the partition plate located on trays 40-55.

[0019] The system for separating 1-hexene from ethylene trimer products according to the present invention, wherein the compression ratio of the pressurizing device is 1.75-3.

[0020] The system for separating 1-hexene from ethylene trimer products according to the present invention, wherein the purification tower has a theoretical plate number of 10-20 and a reflux ratio of 10-15.

[0021] To achieve the above objectives, the present invention also provides a method for separating 1-hexene from ethylene trimer products, comprising the following steps:

[0022] Step 1: The ethylene trimer product is passed into the light-light phase removal tower to separate ethylene and the bottom liquid phase.

[0023] Step 2: The liquid phase from the bottom of the column described in Step 1 is introduced into the adjacent column. The light component flows out from the top of the column, the heavy component flows out from the bottom of the column, and the solvent component is obtained from the side stream.

[0024] Step 3: The light component described in Step 2 is passed into a purification column. A light component byproduct is obtained at the top of the column, and 1-hexene product is obtained at the bottom of the column.

[0025] In this process, the solvent component exchanges heat with the heavy component, and the heavy component after heat exchange returns to the bottom of the partition column, while part of the solvent component after heat exchange returns to the partition column.

[0026] The method for separating 1-hexene from ethylene trimer products according to the present invention includes a process in which the solvent component is pressurized and heated before exchanging heat with the heavy component, and the solvent component after heat exchange is depressurized and cooled, and then partially returned to the partition tower.

[0027] The beneficial effects of this invention are:

[0028] The present invention relates to a system for separating 1-hexene from ethylene trimer products. The solvent component in the side stream of the partition column is pressurized and heated, and then exchanges heat with the heavy component in the bottom of the column. After heat exchange, part of the solvent component is returned to the partition column, and part can be recycled for the ethylene trimer reaction. In this way, the heat source can be effectively utilized, the thermodynamic efficiency can be improved, and at the same time, the number of distillation columns and the equipment footprint can be reduced, thus achieving an overall reduction in economic costs. Attached Figure Description

[0029] Figure 1 This is a process flow diagram of the comparative separation of 1-hexene from ethylene trimer according to the present invention.

[0030] Figure 2 This is a process flow diagram for separating 1-hexene from ethylene trimer according to one embodiment of the present invention.

[0031] In the attached figures, the following labels are used:

[0032] C10-T Decene Recovery Tower

[0033] C6-T Solvent Recovery Tower

[0034] C2-T Light Tower

[0035] S04 gaseous products

[0036] DWC's neighboring tower

[0037] C4-T purification tower

[0038] C3 heat exchanger

[0039] C5 pressurization device

[0040] C6 Pressure Reducing Valve

[0041] C7 Cooler

[0042] C8 separator

[0043] a pre-separation tower

[0044] b Main Tower

[0045] S01 Ethylene trimer

[0046] S02 Liquid Phase Flow

[0047] S03 light components Detailed Implementation

[0048] The technical solution of the present invention will be described in detail below. The following embodiments are implemented under the premise of the technical solution of the present invention and a detailed implementation process is given. However, the protection scope of the present invention is not limited to the following embodiments. Structures or experimental methods that do not specify specific conditions in the following embodiments are generally performed under conventional conditions.

[0049] This invention provides a system for separating 1-hexene from ethylene trimer products, such as... Figure 2 As shown, the system includes a light-light content removal tower C2-T, a partition wall tower DWC, and a purification tower C4-T. In one embodiment, the system of the present invention is suitable for a chromium-ethylene trimerization catalytic system, with the main product being 1-hexene, and small amounts of byproducts such as butene and decene.

[0050] The light-weight product removal tower C2-T is equipped with a top outlet and a bottom outlet. The top outlet is located at the top of the tower, and the bottom outlet is located at the bottom. Additionally, the light-weight product removal tower C2-T has a side stream inlet through which the ethylene trimer product SO1 enters the tower. In one embodiment, after processing, the liquid phase of the ethylene trimer product SO1 enters the light-weight product removal tower C2-T. The light-weight product removal tower C2-T is, for example, a distillation tower. The ethylene trimer product SO1 is distilled within the tower, and the separated ethylene is discharged through the top outlet, while the liquid phase stream SO2 is discharged through the bottom outlet. The present invention does not impose any particular limitation on the light component removal column C2-T. The theoretical number of trays is, for example, 8-20, the feed position is, for example, the 3rd-6th tray, the reflux ratio is, for example, 0.3-0.4, the mass ratio of distillate to feed is, for example, 0.1-0.2, the top pressure is, for example, controlled at 1-2 MPa, and the bottom pressure is, for example, controlled at 1-2 MPa.

[0051] The partition column DWC is connected to the bottom outlet of the light component removal column C2-T. The partition column DWC has a light component outlet at its top, a heavy component outlet at its bottom, and a solvent outlet and a solvent component inlet on its side. In one embodiment, the partition column DWC is equipped with a vertically arranged baffle, dividing it into a pre-separation column a and a main column b. The solvent outlet is located in the main column b.

[0052] In one embodiment, the pre-separation column a has 20-36 theoretical plates, the main column b has 30-66 theoretical plates, and the reflux ratio of the partition column is 10-12. The partition column DWC has a feed inlet located on plates 5-14 of the pre-separation column a. The solvent outlet of the main column b is located on plates 30-50. The upper end of the partition is located on plates 10-20, and the lower end is located on plates 40-55. In this invention, the solvent component inlet of the main column is located on the plate above the solvent outlet. For example, if the solvent outlet is on plate 30, then the solvent component inlet should be on plate 31.

[0053] Divider column DWC is a fully thermally coupled distillation technology. The partition cleverly divides the distillation column into two parts, namely the pre-separation column and the main column. The two columns are connected by mutually flowing thermally coupled gas-liquid streams, which can reduce the backmixing of intermediate components and achieve complete thermal coupling.

[0054] In this invention, a heat exchange device C3 is also provided between the solvent outlet and the heavy component outlet of the partition tower DWC. Specifically, the heat exchange device C3 is connected to both the heavy component outlet and the solvent outlet of the partition tower DWC. The heavy components and solvent components enter the heat exchange device C3 for heat exchange. After heat exchange, the heavy components return to the bottom of the partition tower DWC, while the solvent components are partially extracted via a side stream. In one embodiment, a pressurizing device C5, such as a compressor, is also provided between the solvent outlet of the partition tower DWC and the heat exchange device C3 to pressurize and heat the solvent flowing out of the solvent outlet before it enters the heat exchange device C3. The compression ratio is, for example, 1.75-3. In another embodiment, a pressure reducing valve C6, a cooler C7, and a separator C8 are sequentially provided on the pipeline returning the heat-exchanged solvent to the partition tower DWC through the solvent component inlet. Separator C8 separates the solvent component into solvent (e.g., cyclohexane) and other streams, which include a portion of 1-hexene, light components, and heavy components. The solvent is discharged from the system or recycled back to the reaction unit, while the other streams are returned to the isolation tower.

[0055] This invention uses a partitioned column to separate ethylene trimer products. By optimizing the parameters of the partitioned column, energy consumption is significantly reduced while meeting the purity requirements of the 1-hexene product. Heat exchange is performed between the side-stream solvent and the heavy components in the column bottom, effectively utilizing the heat source and improving thermodynamic efficiency. At the same time, the number of distillation columns and the equipment footprint are reduced, resulting in a significant reduction in overall economic costs.

[0056] Thus, the liquid stream SO2 from the light component removal tower C2-T enters the partition tower DWC through the feed inlet. Specifically, it enters the pre-separation tower a of the partition tower DWC for simple pre-separation, and then enters the main tower b for further component separation. The resulting light component SO3 flows out from the light component outlet at the top of the tower, the resulting heavy component flows out from the heavy component outlet at the bottom of the tower, and the solvent component flows out from the solvent outlet. The light component is a liquid phase, including byproducts and butene and 1-hexene; the solvent includes at least one of cyclohexane, toluene, methylcyclohexane, and heptane; the heavy component is octene and C8+ olefin byproducts, including decene, which can be recovered and reused in other processes.

[0057] The solvent component and a portion of the heavy components are fed into heat exchanger C3 for heat exchange, for example, a non-contact heat exchange. The heavy components after heat exchange are returned to the bottom of the partition tower DWC, while the solvent component after heat exchange is partially returned to the partition tower DWC and partially recycled back to the ethylene trimer reactor.

[0058] In one embodiment, the solvent component is pressurized and heated by the pressurizing device C5 and then passed into the heat exchange device C3 to exchange heat with the heavy components, providing heat to the bottom of the tower. After heat exchange, the solvent component is depressurized by the pressure reducing valve C6, cooled by the cooler C7, and separated by the separator C8. Part of it is returned to the partition tower DWC, and part is recycled back to the ethylene trimer reactor. The heavy components after heat exchange are returned to the bottom of the partition tower DWC.

[0059] Purification column C4-T is connected to the light component outlet of the adjacent column DWC. Purification column C4-T has a butene outlet at its top and a product outlet at its bottom. In one embodiment, the purification column is, for example, a distillation column with, for example, 10-20 theoretical plates, a reflux ratio for example, 10-18, and an operating pressure for example, 0.05-0.2 MPa.

[0060] The light component SO3 obtained from the light component removal tower C2-T is passed into the purification tower C4-T to separate the light component byproduct (mainly butene) and the product 1-hexene. The light component byproduct can be flared.

[0061] The system described above is used for the separation of 1-hexene from ethylene trimer products. The separation method includes the following steps:

[0062] Step 1: The ethylene trimer product is passed into the light-light phase removal tower to separate ethylene and the bottom liquid phase.

[0063] Step 2: The liquid phase from the bottom of the column described in Step 1 is introduced into the adjacent column, the light component flows out from the top of the column, the heavy component flows out from the bottom of the column, and the solvent component is obtained from the side stream.

[0064] Step 3: The light component described in Step 2 is passed into a purification column. A light component byproduct is obtained at the top of the column, and 1-hexene product is obtained at the bottom of the column.

[0065] In this process, the solvent component exchanges heat with the heavy component, and the heavy component after heat exchange returns to the bottom of the partition column, while part of the solvent component after heat exchange returns to the partition column.

[0066] In one embodiment, the solvent component is pressurized and heated before exchanging heat with the heavy component. After heat exchange, the solvent component is depressurized and cooled, and a portion of it is returned to the partition tower.

[0067] In one specific embodiment, the method for separating 1-hexene from ethylene trimer products of the present invention is as follows: ethylene trimerization is carried out in a reactor, and the resulting reaction liquid enters the light component removal tower C2-T. The bottom stream of the light component removal tower C2-T first enters the partition wall tower DWC for separation. After separation in the partition wall tower DWC, the top stream of the partition wall tower DWC yields light components butene and 1-hexene. The top stream enters the purification tower C4-T to complete the purification of 1-hexene and product collection. The side stream of the partition wall tower DWC yields the solvent component, which is pressurized and heated by a compressor to exchange heat with the heavy component in the bottom of the tower. The obtained solvent component after heat exchange is separated by depressurization and cooling and returned to the reactor to continue the ethylene trimerization reaction. Octene and C8 and above olefin byproducts are obtained from the bottom of the partition wall tower DWC, which can be recycled.

[0068] In this invention, the C10-T decene recovery tower and the C6-T solvent recovery tower are combined into a partition tower. The side stream is used as an intermediary between the heat pump and the partition tower, realizing an effective combination of intermediate heat exchange, heat pump technology and partition tower. The intermediate heat exchanger replaces the high-quality heat source with a relatively inexpensive heating medium, reducing energy consumption, saving operating costs and reducing the economic cost of 1-hexene.

[0069] The technical solution of the present invention will be described in detail below through specific embodiments. The present invention does not limit the specific parameters of the ethylene trimerization process. The ethylene trimerization product used in the following embodiments is the product obtained by the chromium ethylene trimerization catalytic system.

[0070] Example 1

[0071] The separation of 1-hexene in ethylene trimerization using a partitioned-wall column is described above, and the parameters of the various devices used are as follows:

[0072] Parameters of the light component removal column C2-T: theoretical number of trays: 10, feed position: 3rd tray, reflux ratio: 0.378, ratio of distillate to feed: 0.110, top pressure: 1.5 MPa, bottom pressure: 1.5 MPa.

[0073] Divider column DWC parameters: Divider column operating pressure is 0.1 MPa, pre-separation column has 24 trays, main column has 44 trays, reflux ratio is 10.90, pre-separation column feed position is the 7th tray, side stream solvent component exit position is the 35th tray, upper end of the divider is the 20th tray, lower end of the divider is the 37th tray, liquid phase distribution ratio (distribution ratio of liquid phase extraction flow) is 0.72, gas phase distribution ratio (distribution ratio of gas phase extraction flow) is 0.53, and compression ratio is 1.75.

[0074] The C4-T purification column operates at a pressure of 0.1 MPa, has 12 theoretical plates, and a reflux ratio of 16.18.

[0075] The 1-hexene product obtained using the above-mentioned device has a purity of 99.5%, and its energy consumption is reduced by 29.5% compared with the conventional process in the comparative example, resulting in a saving of 16.21% in annual economic costs.

[0076] The feed and product results for Example 1 are shown in Table 1.

[0077] Table 1. Feed and Product Results of Example 1

[0078]

[0079] The mass ratio refers to the percentage of the substance in the entire logistics.

[0080] Example 2

[0081] The separation of 1-hexene in ethylene trimerization using a partitioned-wall column is described above, and the parameters of the various devices used are as follows:

[0082] Parameters of the light component removal column C2-T: theoretical number of trays is 10, feed position is the 3rd tray, reflux ratio is 0.378, distillate to feed ratio is 0.110, top pressure is 1.5 MPa, bottom pressure is 1.5 MPa.

[0083] Divider column DWC parameters: Divider column operating pressure is 0.1 MPa, pre-separation column has 32 trays, main column has 56 trays, reflux ratio is 10.85, pre-separation column feed position is the 12th tray, side stream solvent component exit position is the 43rd tray, upper end of the divider is the 19th tray, lower end of the divider is the 47th tray, liquid phase distribution ratio is 0.71, gas phase distribution ratio is 0.53, and compression ratio is 1.80.

[0084] The purification column C4-T operates at a pressure of 0.1 MPa, has a theoretical plate number of 18, and a reflux ratio of 15.86.

[0085] The 1-hexene product obtained using the above-mentioned device has a purity of 99.5%, and its energy consumption is reduced by 22.94% compared with the conventional process in the comparative example, saving 14.90% of the annual economic cost.

[0086] The feed and product results for Example 2 are shown in Table 2.

[0087] Table 2. Feed and Product Results of Example 2

[0088]

[0089] The mass ratio refers to the percentage of the substance in the entire logistics.

[0090] Example 3

[0091] The separation of 1-hexene in ethylene trimerization using a partitioned-wall column is described above, and the parameters of the various devices used are as follows:

[0092] Parameters of the light component removal column C2-T: theoretical plate number is 10, feed position is 3, reflux ratio is 0.378, distillate to feed ratio is 0.110, column top pressure is 1.5 MPa, column bottom pressure is 1.5 MPa.

[0093] Divider column DWC parameters: Divider column operating pressure is 0.1 MPa, pre-separation column has 36 trays, main column has 66 trays, reflux ratio is 10.5, pre-separation column feed position is the 14th tray, side stream solvent component exit position is the 51st tray, upper end of the divider is the 19th tray, lower end of the divider is the 57th tray, liquid phase distribution ratio is 0.72, gas phase distribution ratio is 0.53, and compression ratio is 1.75.

[0094] The purification column C4-T operates at a pressure of 0.1 MPa, has 14 theoretical plates, and a reflux ratio of 17.62.

[0095] The 1-hexene product obtained using the above-mentioned device has a purity of 99.5%, and its energy consumption is reduced by 22.80% compared with the traditional process, saving 13.60% of the annual economic cost.

[0096] The feed and product results for Example 3 are shown in Table 3.

[0097] Table 3. Feed and Product Results of Example 3

[0098]

[0099]

[0100] The mass ratio refers to the percentage of the substance in the entire logistics.

[0101] Comparative Example

[0102] The comparative process is as follows: Figure 1 As shown, the process parameters for each device are:

[0103] Parameters of the light component removal column C2-T: theoretical number of trays is 10, feed position is the 3rd tray, reflux ratio is 0.378, distillate to feed ratio is 0.110, top pressure is 1.5 MPa, bottom pressure is 1.5 MPa.

[0104] The pressure of the decene recovery tower C10-T is 0.1 MPa, the number of trays is 31, the feed position is the 23rd tray, and the reflux ratio is 0.592.

[0105] The solvent purification tower C6-T has a pressure of 0.1 MPa, 54 trays, a feed position on the 23rd tray, and a reflux ratio of 6.91.

[0106] The C4-T purification column operates at a pressure of 0.1 MPa, has 12 theoretical plates, and a reflux ratio of 16.18.

[0107] The purity of the 1-hexene product obtained using the above-mentioned apparatus is 99.5%.

[0108] The feed and product results for the comparative studies are shown in Table 4.

[0109] Table 4 Comparative Feed and Product Results

[0110]

[0111] The mass ratio refers to the percentage of the substance in the entire logistics.

[0112] As shown in Tables 1-4, compared with the conventional process of the comparative example, the purity of 1-hexene obtained by the technical solution of the present invention is basically 99.5%. Under the condition that the purity of 1-hexene obtained is 99.5%, the energy consumption of the partition wall tower technology solution of the present invention is reduced by 22.80% compared with the conventional process, and the annual economic cost is saved by 13.60%.

[0113] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. An apparatus for separating 1-hexene from ethylene trimer products, characterized in that, include: The light-weight removal tower is equipped with a top outlet and a bottom outlet. The partition wall column is connected to the bottom outlet of the light component removal column. The top of the partition wall column is provided with a light component outlet, the bottom of the column is provided with a heavy component outlet, and the side line is provided with a solvent outlet and a solvent component inlet. A purification tower is connected to the light component outlet of the partition tower. The purification tower has a butene outlet at the top and a 1-hexene outlet at the bottom. The partition wall tower is equipped with a baffle plate that divides it into a pre-separation tower and a main tower. The solvent component after heat exchange is partially returned to the main tower. The pre-separation tower has 20-36 theoretical plates, and the main tower has 30-66 theoretical plates. The solvent outlet of the main tower is located at plate 30-50. A heat exchange device is also provided between the solvent outlet and the heavy component outlet of the partition wall tower to allow heat exchange between the solvent component flowing out of the solvent outlet and the heavy component flowing out of the heavy component outlet. The heavy component after heat exchange returns to the bottom of the partition wall tower, and a portion of the solvent component after heat exchange returns to the partition wall tower.

2. The apparatus for separating 1-hexene from ethylene trimer products according to claim 1, characterized in that, A pressurizing device is also provided between the solvent outlet of the partition tower and the heat exchange device, so that the solvent components flowing out of the solvent outlet are pressurized and heated before entering the heat exchange device.

3. The apparatus for separating 1-hexene from ethylene trimer products according to claim 1, characterized in that, The side of the light-light product removal tower is provided with an inlet, through which the ethylene trimer product enters the light-light product removal tower.

4. The apparatus for separating 1-hexene from ethylene trimer products according to claim 1, characterized in that, The reflux ratio of the adjacent tower is 10-12.

5. The apparatus for separating 1-hexene from ethylene trimer products according to claim 1, characterized in that, The partition tower is also provided with a feed inlet located on the 5th to 14th trays of the pre-separation tower. The solvent component inlet of the main tower is located on the tray above the solvent outlet. The upper end of the partition is located on the 10th to 20th trays, and the lower end of the partition is located on the 40th to 55th trays.

6. The apparatus for separating 1-hexene from ethylene trimer products according to claim 2, characterized in that, The compression ratio of the pressurizing device is 1.75-3.

7. The apparatus for separating 1-hexene from ethylene trimer products according to claim 1, characterized in that, The purification column has a theoretical plate number of 10-20 and a reflux ratio of 10-15.

8. A method for separating 1-hexene from ethylene trimer products, characterized in that, Using the apparatus according to any one of claims 1-7 includes the following steps: Step 1: The ethylene trimer product is passed into the light-light phase removal tower to separate ethylene and the bottom liquid phase. Step 2: The liquid phase from the bottom of the column described in Step 1 is introduced into the adjacent column. The light component flows out from the top of the column, the heavy component flows out from the bottom of the column, and the solvent component is obtained from the side stream. Step 3: The light component described in Step 2 is passed into a purification column. A light component byproduct is obtained at the top of the column, and 1-hexene product is obtained at the bottom of the column. In this process, the solvent component exchanges heat with the heavy component, and the heavy component after heat exchange returns to the bottom of the partition column, while part of the solvent component after heat exchange returns to the partition column.

9. The method for separating 1-hexene from ethylene trimer products according to claim 8, characterized in that, The solvent component is pressurized and heated before exchanging heat with the heavy component. After heat exchange, the solvent component is depressurized and cooled, and part of it is returned to the partition tower.

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