Separation device of azeotropic mixture and production system of 4-methyl-2-pentanone
By combining a distillation column and a dehydrogenation reaction column into a separation device, the problem of difficult separation of azeotropic mixtures was solved, achieving efficient and low-energy separation of 4-methyl-2-pentanone and C9, and simplifying the process flow.
Patent Information
- Application Number
- CN202520012025.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-01-02
AI Technical Summary
Existing technologies struggle to efficiently separate azeotropic mixtures, especially azeotropes of 4-methyl-2-pentanone and C9, resulting in low purity and high energy consumption. Furthermore, extractive distillation requires high energy consumption for solvent recovery, impacting reaction and product quality.
The separation unit, which includes a first distillation column, a phase separation device, a dehydrogenation reaction column, and a third distillation column, achieves efficient separation through distillation and dehydrogenation reaction, simplifies the process flow, and reduces system circulation and energy consumption.
The separation of high-purity 4-methyl-2-pentanone and C9 was achieved, simplifying the process, reducing energy consumption, and avoiding the use of multi-stage reactions and distillation equipment.
Smart Images
Figure CN223861336U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of separation and purification, and more specifically, to a separation device for azeotropic mixtures and a production system for 4-methyl-2-pentanone. Background Technology
[0002] Currently, conventional distillation or extractive distillation are commonly used to separate organic mixtures. If azeotropic substances are present in the mixture, conventional distillation is difficult to obtain high-purity target products, and the large circulation volume results in high energy consumption. Extractive distillation uses solvents such as toluene as extractants. Since the extractants need to be recycled, energy consumption is high, and incomplete separation can have a significant impact on the reaction and the product.
[0003] In view of the above, this utility model is hereby proposed. Utility Model Content
[0004] The purpose of this invention is to provide a separation device for azeotropic mixtures and a production system for 4-methyl-2-pentanone, which aims to improve at least one of the problems mentioned in the background art.
[0005] The embodiments of this utility model are implemented as follows:
[0006] In a first aspect, the present invention provides a separation device for an azeotropic mixture, comprising a first distillation column, a phase separation device, a dehydrogenation reaction column, a second distillation column, and a third distillation column;
[0007] The first distillation column has outlets at the top, middle and bottom. The top outlet of the first distillation column is connected to the inlet of the phase separation unit, the middle outlet of the first distillation column is connected to the inlet of the dehydrogenation reaction column, and the bottom outlet of the first distillation column is connected to the inlet of the second distillation column.
[0008] The phase separation device has discharge ports at both the top and bottom. The top discharge port of the phase separation device is connected to the wastewater discharge pipe, and the bottom discharge port of the phase separation device is connected to the feed port of the second distillation column.
[0009] The second distillation column has outlets at both the top and bottom. The top outlet of the second distillation column is connected to the first light component phase discharge pipe, and the bottom outlet of the second distillation column is connected to the first ketone collection pipe.
[0010] The dehydrogenation reaction tower has outlets at both the top and bottom. The top outlet of the dehydrogenation reaction tower is connected to the second ketone collection pipe, and the bottom outlet of the dehydrogenation reaction tower is connected to the inlet of the third distillation tower.
[0011] The third distillation column has outlets at the top, middle, and bottom. The top outlet of the third distillation column is connected to the second light component phase discharge pipe, the middle outlet of the third distillation column is connected to the C9 collection pipe, and the bottom outlet of the third distillation column is connected to the heavy component phase collection pipe.
[0012] In an optional embodiment, the first light component phase discharge pipe is connected to the feed inlet of the first distillation column.
[0013] In an optional embodiment, the second light component phase discharge pipe is connected to the feed inlet of the dehydrogenation reaction tower.
[0014] In an optional embodiment, the first distillation column has 6 to 50 trays.
[0015] In an optional embodiment, the second distillation column has 6 to 50 trays.
[0016] In an optional implementation, the third distillation column has 6 to 50 trays.
[0017] In an optional embodiment, a first top reflux pipe is provided at the top of the first distillation column, a first reflux port is provided at the upper part of the first distillation column, one end of the first top reflux pipe is connected to the top outlet of the first distillation column, the other end of the first top reflux pipe is connected to the first reflux port, and a first condenser is provided on the first top reflux pipe.
[0018] On the top reflux pipe of the first tower, there is a phase separation device connecting pipe located between the first condenser and the first reflux port. The phase separation device connecting pipe is connected to the feed port of the phase separation device.
[0019] In an optional embodiment, a second top reflux pipe is provided at the top of the second distillation column, a second reflux port is provided at the upper part of the second distillation column, one end of the second top reflux pipe is connected to the top outlet of the second distillation column, the other end of the second top reflux pipe is connected to the second reflux port, and a second condenser is provided on the second top reflux pipe.
[0020] The material discharge pipe at the top of the first tower is connected to the reflux pipe at the top of the second tower, and the connection point is located between the second condenser and the second reflux port.
[0021] In an optional embodiment, a third top reflux pipe is provided at the top of the third distillation column, a third reflux port is provided at the upper part of the third distillation column, one end of the third top reflux pipe is connected to the top outlet of the third distillation column, the other end of the third top reflux pipe is connected to the third reflux port, and a third condenser is provided on the third top reflux pipe.
[0022] The material discharge pipe at the top of the second column is connected to the reflux pipe at the top of the third column, and the connection point is located between the third condenser and the third reflux port.
[0023] Secondly, this utility model provides a production system for 4-methyl-2-pentanone, including a separation device as described in any of the foregoing embodiments.
[0024] The beneficial effects of this utility model embodiment are:
[0025] The separation device provided by this invention can separate mixtures containing water, 4-methyl-2-pentanone, 4-methyl-2-pentanol, C9, and heavy components. It effectively solves the problems of difficult separation of 4-methyl-2-pentanone and C9 when separating and purifying 4-methyl-2-pentanone, due to the presence of many azeotropic components in the stream containing water, 4-methyl-2-pentanone, 4-methyl-2-pentanol, and C9, especially the azeotrope of C9 with 4-methyl-2-pentanone, which makes it difficult to obtain high-purity 4-methyl-2-pentanone. It also addresses the problems of complex operation, high energy consumption, and unsatisfactory C9 separation effect of current separation technologies for mixtures containing azeotropes. The device features a small system circulation volume and low energy consumption. Furthermore, the dehydrogenation of 4-methyl-2-pentanol to 4-methyl-2-pentanone simultaneously achieves the distillation separation of alcohol and ketone, eliminating the need for subsequent multi-stage reaction devices and multi-stage distillation separation devices, resulting in a simple process structure. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of the separation device provided in an embodiment of the present invention.
[0028] Icons: T101 - First distillation column; V106 - Phase separation unit; R102 - Dehydrogenation reaction column; T103 - Second distillation column; T104 - Third distillation column; 01 - Azeotropic mixture inlet; 02 - Phase separation unit connection pipe; 03 - Dehydrogenated material inlet; 04 - Third distillation column material inlet; 07 - Dehydrogenated heavy component discharge pipe; 09 - Second ketone outlet pipe; 11 - Second distillation column material inlet; 12 - Wastewater discharge pipe; 13 - First light component phase discharge pipe; 14 - First ketone outlet pipe; 16 - Second light component phase discharge pipe; 17 - C9 outlet pipe; 18 - Heavy component phase outlet pipe; 101 - First condenser; 102 - Second condenser; 103 - Third condenser; 104 - Fourth condenser. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0033] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0034] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0035] like Figure 1 As shown, this utility model embodiment provides a separation device for an azeotropic mixture, including a first distillation column T101, a phase separation device V106, a dehydrogenation reaction column R102, a second distillation column T103, and a third distillation column T104;
[0036] The first distillation column T101 has outlets at the top, middle and bottom. The top outlet of the first distillation column T101 is connected to the inlet of the phase separation device V106, the middle outlet of the first distillation column T101 is connected to the inlet of the dehydrogenation reaction column R102, and the bottom outlet of the first distillation column T101 is connected to the inlet of the second distillation column T103.
[0037] The phase separation device V106 has discharge ports at both the top and bottom. The top discharge port of the phase separation device V106 is connected to the wastewater discharge pipe 12, and the bottom discharge port of the phase separation device V106 is connected to the feed port of the second distillation column T103.
[0038] The second distillation column T103 has discharge ports at both the top and bottom. The top discharge port of the second distillation column T103 is connected to the first light component phase discharge pipe 13, and the bottom discharge port of the second distillation column T103 is connected to the first ketone collection pipe 14.
[0039] The dehydrogenation reaction tower R102 has outlets at both the top and bottom. The top outlet of the dehydrogenation reaction tower R102 is connected to the second ketone collection pipe 09, and the bottom outlet of the dehydrogenation reaction tower R102 is connected to the inlet of the third distillation tower T104.
[0040] The third distillation column T104 has discharge ports at the top, middle and bottom. The top discharge port of the third distillation column T104 is connected to the second light component phase discharge pipe 16, the middle discharge port of the third distillation column T104 is connected to the C9 collection pipe 17, and the bottom discharge port of the third distillation column T104 is connected to the heavy component phase collection pipe 18.
[0041] The separation device provided by this utility model is used as follows:
[0042] A mixture containing water, 4-methyl-2-pentanone, 4-methyl-2-pentanol, C9, and heavy components is fed to the first distillation column T101 for distillation through the azeotropic mixture inlet pipe 01. The azeotropic mixture obtained from the top of the column, containing water, 4-methyl-2-pentanone, and C9 (1,3,5-trimethylcyclohexane and its isomers), enters the phase separation unit V106. The side stream containing 4-methyl-2-pentanol and 4-methyl-2-pentanone enters the dehydrogenation reaction column R102. The bottom stream containing 4-methyl-2-pentanol and heavy components enters the third distillation column T104 through the third distillation column feed inlet pipe 04.
[0043] The mixture of water and 4-methyl-2-pentanone produced at the top of the first distillation column T101 flows to the phase separation device V106. After phase separation by the phase separation device V106, the upper aqueous phase, mainly containing water, flows through the wastewater discharge pipe 12 to the wastewater treatment unit. The lower oil phase, mainly containing 4-methyl-2-pentanone and a small amount of water, enters the second distillation column T103 through the material inlet pipe 11. After separation by the second distillation column T103, the water and 4-methyl-2-pentanone stream obtained at the top of the column is collected through the first light component phase collection pipe, and the 4-methyl-2-pentanone stream with a purity of more than 95% is obtained at the bottom of the column and is collected through the first ketone collection pipe 14.
[0044] The stream containing 4-methyl-2-pentanol and 4-methyl-2-pentanone from the side stream of the first distillation column T101 enters the dehydrogenation reaction column R102 through the dehydrogenation feed inlet pipe 03 for dehydrogenation reaction and distillation. The 4-methyl-2-pentanone stream with a purity of over 95% obtained at the top of the column is collected through the second ketone outlet pipe 09, and the heavy components obtained at the bottom of the column are fed into the third distillation column T104 through the dehydrogenation heavy component outlet pipe 07.
[0045] The bottom stream of the first distillation column T101, containing 4-methyl-2-pentanol and heavy components, enters the third distillation column through the feed inlet pipe 04 for distillation. The top stream of the third distillation column T104, containing 4-methyl-2-pentanol, is collected through the second light component phase discharge pipe 16. The side stream is collected through the C9 collection pipe 17, which contains C9 by-product with a purity ≥95%. The bottom stream contains heavy components, and the heavy component phase in the bottom stream is collected through the heavy component phase collection pipe 18.
[0046] The azeotropic mixture separation device provided by this invention can separate a mixture containing water, 4-methyl-2-pentanone, 4-methyl-2-pentanol, C9, and heavy components to produce high-purity 4-methyl-2-pentanone and C9.
[0047] Optionally, the first distillation column T101 can be a multi-functional distillation column, specifically a packed column or a plate column. The second distillation column T103 and the third distillation column T104 are ordinary distillation columns, specifically packed columns or plate columns.
[0048] Optionally, the phase separation device V106 is a phase separation tank.
[0049] Optionally, the first light component phase discharge pipe 13 is connected to the feed inlet of the first distillation column T101.
[0050] The top of the second distillation column T103 yields a stream containing water and 4-methyl-2-pentanone. This stream is collected through the first light component phase discharge pipe and recycled back into the first distillation column T101 for further separation.
[0051] Optionally, the second light component phase discharge pipe 16 is connected to the feed port of the dehydrogenation reaction tower R102.
[0052] The 4-methyl-2-pentanol-containing stream obtained from the top of the third distillation column T104 is recycled back to the dehydrogenation reaction column R102 through the second light component phase discharge pipe 16, thus realizing the recovery and utilization of 4-methyl-2-pentanol.
[0053] Optionally, in order to achieve better separation and purification results, the number of trays in the first distillation column T101 is 6 to 50.
[0054] Optionally, in order to achieve better separation and purification results, the number of trays in the second distillation column T103 is 6 to 50.
[0055] Optionally, in order to achieve better separation and purification results, the number of trays in the third distillation column T104 is 6 to 50.
[0056] Optionally, a first top reflux pipe is provided at the top of the first distillation column T101, a first reflux port is provided at the upper part of the first distillation column T101, one end of the first top reflux pipe is connected to the top outlet of the first distillation column T101, the other end of the first top reflux pipe is connected to the first reflux port, and a first condenser 101 is provided on the first top reflux pipe;
[0057] On the top reflux pipe of the first tower, a phase separation device connecting pipe 02 is connected between the first condenser 101 and the first reflux port. The phase separation device connecting pipe is connected to the feed port of the phase separation device.
[0058] Optionally, a second top reflux pipe is provided at the top of the second distillation column T103, and a second reflux port is provided at the upper part of the second distillation column T103. One end of the second top reflux pipe is connected to the top outlet of the second distillation column T103, and the other end of the second top reflux pipe is connected to the second reflux port. A second condenser 102 is provided on the second top reflux pipe.
[0059] The material discharge pipe at the top of the first tower is connected to the reflux pipe at the top of the second tower, and the connection point is located between the second condenser 102 and the second reflux port.
[0060] Optionally, a third top reflux pipe is provided at the top of the third distillation column T104, a third reflux port is provided at the upper part of the third distillation column T104, one end of the third top reflux pipe is connected to the top outlet of the third distillation column T104, the other end of the third top reflux pipe is connected to the third reflux port, and a third condenser 103 is provided on the third top reflux pipe.
[0061] The material discharge pipe at the top of the second tower is connected to the reflux pipe at the top of the third tower, and the connection point is located between the third condenser 103 and the third reflux port.
[0062] Optionally, a fourth top reflux pipe is provided at the top of the dehydrogenation reaction tower R102, a fourth reflux port is provided at the upper part of the dehydrogenation reaction tower R102, one end of the fourth top reflux pipe is connected to the top discharge port of the dehydrogenation reaction tower R102, the other end of the fourth top reflux pipe is connected to the fourth reflux port, and a fourth condenser 104 is provided on the fourth top reflux pipe.
[0063] The second ketone outlet pipe 09 is connected to the fourth column top reflux pipe, and the connection point is located between the fourth condenser 104 and the fourth reflux port.
[0064] This invention also provides a production system for 4-methyl-2-pentanone, including the separation device provided in this invention.
[0065] In the production of 4-methyl-2-pentanone, the reaction product typically includes a mixture of water, 4-methyl-2-pentanol, 4-methyl-2-pentanone, and C9. The separation device provided in this embodiment of the invention can separate these components to obtain 4-methyl-2-pentanone and C9 with higher purity.
[0066] Example
[0067] The mixture containing 2.54% water, 20.05% 4-methyl-2-pentanol, 55.28% 4-methyl-2-pentanone, and approximately 19.70% C9 was fed into the first distillation column T101 for separation.
[0068] The theoretical plate number of the first distillation column T101 is 6–50, with a top temperature of 94℃ and a bottom temperature of 127℃; the theoretical plate number of the second distillation column T103 is 6–50, with a top temperature of 83℃, a bottom temperature of 115℃, and a reflux ratio of 0.5–5; the theoretical plate number of the third distillation column T104 is 6–50, with a top temperature of 100℃ and a bottom temperature of 130℃; the dehydrogenation reaction column R102 has a reaction temperature of 170–260℃ and a pressure of 0.1 MPa–10 MPa.
[0069] The content of each substance at different locations in this embodiment is shown in Table 1:
[0070] Table 1 Content of each substance at different locations
[0071]
[0072] As can be seen from the examples, the T101 side stream material, after undergoing the efficient dehydrogenation reaction in R102, yields a high-purity 4-methyl-2-pentanone (99.14%) at the top of the column, which can be directly collected as a product. In contrast, the comparative example uses a conventional batch or fixed-bed reactor, resulting in poor dehydrogenation reaction. 4-methyl-2-pentanone (78%) cannot be directly collected and must be returned to T101 for distillation separation. This leads to the disadvantages of large circulation volume and high energy consumption, as well as system complexity.
[0073] In summary, the separation device provided in this embodiment of the present invention can be used to separate a mixture of water, 4-methyl-2-pentanol, 4-methyl-2-pentanone and C9, producing 4-methyl-2-pentanone and C9 with high purity.
[0074] The separation device provided by this utility model achieves the separation of the mixture into a fore-distillate, a middle-distillate, and a post-distillate in the first distillation column T101. In the dehydrogenation reaction column R102, 4-methyl-2-pentanol is dehydrogenated to generate 4-methyl-2-pentanone, and the alcohol and ketone are separated by distillation. The reaction product is then passed through the second distillation column T103 to remove light components and obtain high-purity 4-methyl-2-pentanone.
[0075] The separation device provided by this invention effectively solves the problems encountered in the separation and purification of 4-methyl-2-pentanone, where numerous azeotropic components exist in the stream containing water, 4-methyl-2-pentanone, 4-methyl-2-pentanol, and C9. In particular, the azeotrope between C9 and 4-methyl-2-pentanone makes the separation of 4-methyl-2-pentanone from C9 difficult, resulting in the difficulty of obtaining high-purity 4-methyl-2-pentanone. Furthermore, current separation technologies for mixtures containing azeotropes are complex to operate, energy-intensive, and have unsatisfactory C9 separation effects. This device features a small system circulation volume and low energy consumption. Moreover, the dehydrogenation of 4-methyl-2-pentanol to generate 4-methyl-2-pentanone simultaneously achieves the distillation separation of alcohol and ketone, eliminating the need for subsequent multi-stage reaction devices and multi-stage distillation separation devices, thus greatly simplifying the process.
[0076] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A separation apparatus for an azeotropic mixture, characterized in that, It includes a first distillation column, a phase separation unit, a dehydrogenation reaction column, a second distillation column, and a third distillation column; The first distillation column has outlets at the top, middle and bottom. The top outlet of the first distillation column is connected to the inlet of the phase separation device, the middle outlet of the first distillation column is connected to the inlet of the dehydrogenation reaction column, and the bottom outlet of the first distillation column is connected to the inlet of the second distillation column. The phase separation device has discharge ports at both the top and bottom. The top discharge port of the phase separation device is connected to a wastewater discharge pipe, and the bottom discharge port of the phase separation device is connected to the feed port of the second distillation column. The second distillation column has outlets at both the top and bottom. The top outlet of the second distillation column is connected to the first light component phase discharge pipe, and the bottom outlet of the second distillation column is connected to the first ketone collection pipe. The dehydrogenation reaction tower has outlets at both the top and bottom. The top outlet of the dehydrogenation reaction tower is connected to the second ketone collection pipe, and the bottom outlet of the dehydrogenation reaction tower is connected to the inlet of the third distillation tower. The third distillation column has outlets at the top, middle, and bottom. The top outlet of the third distillation column is connected to the second light component phase discharge pipe, the middle outlet of the third distillation column is connected to the C9 collection pipe, and the bottom outlet of the third distillation column is connected to the heavy component phase collection pipe.
2. The separation device according to claim 1, characterized in that, The first light component phase discharge pipe is connected to the feed inlet of the first distillation column.
3. The separation device according to claim 1, characterized in that, The second light component phase discharge pipe is connected to the feed inlet of the dehydrogenation reaction tower.
4. The separation device according to claim 1, characterized in that, The first distillation column has 6 to 50 trays.
5. The separation device according to claim 1, characterized in that, The second distillation column has 6 to 50 trays.
6. The separation device according to claim 1, characterized in that, The third distillation column has 6 to 50 trays.
7. The separation device according to claim 1, characterized in that, The first distillation column is provided with a first top reflux pipe at the top of the column, and a first reflux port is provided at the upper part of the first distillation column. One end of the first top reflux pipe is connected to the top outlet of the first distillation column, and the other end of the first top reflux pipe is connected to the first reflux port. A first condenser is provided on the first top reflux pipe. On the first tower top reflux pipe, a phase separation device connecting pipe is connected between the first condenser and the first reflux port, and the phase separation device connecting pipe is connected to the feed port of the phase separation device.
8. The separation device according to claim 6, characterized in that, The second distillation column is provided with a second top reflux pipe at the top of the column, and a second reflux port is provided at the upper part of the second distillation column. One end of the second top reflux pipe is connected to the top outlet of the second distillation column, and the other end of the second top reflux pipe is connected to the second reflux port. A second condenser is provided on the second top reflux pipe. The material discharge pipe at the top of the first tower is connected to the reflux pipe at the top of the second tower, and the connection point is located between the second condenser and the second reflux port.
9. The separation device according to claim 8, characterized in that, The third distillation column is provided with a third top reflux pipe at the top of the column, and a third reflux port is provided at the upper part of the third distillation column. One end of the third top reflux pipe is connected to the top outlet of the third distillation column, and the other end of the third top reflux pipe is connected to the third reflux port. A third condenser is provided on the third top reflux pipe. The material discharge pipe at the top of the second tower is connected to the reflux pipe at the top of the third tower, and the connection point is located between the third condenser and the third reflux port.
10. A system for producing 4-methyl-2-pentanone, characterized in that, Includes the separation device as described in any one of claims 1 to 9.