CN116020149A - Cyclohexanone refining device and method - Google Patents

Abstract

The invention provides a cyclohexanone refining device and a method, wherein the device comprises the following steps: a separation unit of a partition tower, which is used for processing a crude alcohol ketone material prepared by cyclohexanol dehydrogenation reaction to prepare a refined alcohol ketone mixture; the dividing wall column separation unit includes a dividing wall column; a ketone refining unit for separating refined alcohol-ketone mixture prepared by the bulkhead tower to obtain refined ketone and cyclic alcohol of the ketone tower; by arranging the partition tower, the coupling of the processes of light removal and heavy impurity removal is realized in a single tower by utilizing the partition tower technology, the separation characteristics of the partition tower are fully utilized, and the refined alcohol-ketone mixture with high purity is obtained, so that the product yield is improved, the cyclohexanone content in the circulating alcohol is obviously reduced, and the equipment investment and the energy consumption are saved; by arranging the circulating alcohol refining unit, the circulating alcohol is separated from the impurity-containing alcohol material enriched with intermediate accumulated impurities, which is separated by the separation unit of the partition tower, and the utilization rate of the cyclohexanol material is improved.

Description

Cyclohexanone refining device and method

Technical Field

The invention relates to the technical field of cyclohexanone preparation, in particular to a cyclohexanone refining device and method.

Background

The cyclohexanone is mainly applied to industries such as fiber, rubber, medicine, organic solvent and the like, and is an important chemical intermediate raw material for producing products such as caprolactam, adipic acid, nylon 66 and the like. The production and preparation of the cyclohexanol are generally realized by gas-phase catalytic dehydrogenation of the cyclohexanol in the industry, the once-through conversion rate of the cyclohexanol is generally 50-60%, and impurities are generated by side reactions. Thus, in existing cyclohexanone preparation processes, a separation scheme with other mixture of heteroalcohol-containing ketones must be included. Because the boiling point of the alcohol ketone is close to that of the alcohol ketone, and the boiling point of the alcohol ketone is higher under normal pressure, the industrial alcohol ketone separation process is generally realized by reduced pressure rectification.

The traditional process is roughly divided into three steps: "light removal+refined ketone+heavy removal". The light component removal step is to separate light impurities in the crude alcohol ketone mixture through the light component removal tower by vacuum distillation, and to reduce the ketone content in the light oil and improve the recovery rate of cyclohexanone, the reflux ratio of the light component removal tower is usually controlled to be very high, or a light two-tower is added to carry out secondary distillation to recover the cyclohexanone in the externally thrown light oil; "refined ketone": the refined ketone product is obtained through the reduced pressure rectification of the ketone tower, so that the number of theoretical plates required by the ketone tower is more, and the separation efficiency is low; the heavy impurities in the cyclohexanol are separated through the alcohol tower under reduced pressure, so that the influence of more heavy impurities in the circulating cyclohexanol on the dehydrogenation reaction is avoided. The alcohol ketone separation process is realized by at least 3-4 vacuum rectification systems, a large amount of energy is consumed, equipment investment is high, wherein the energy consumption of light component removal is about 40-60% of the total energy consumption of alcohol ketone separation, and the energy consumption of refined ketone and heavy component removal is about one level. In addition, as the whole separation process is a decompression operation, components with boiling points close to that of cyclohexanol under the decompression condition cannot be effectively separated, and accumulation of impurities in cyclohexanol materials can be caused.

CN111662171a discloses a method for removing cyclohexanone and intermediate components in cyclohexanol, separating crude alcohol in the kettle of a ketone tower by using a partition tower, returning cyclohexanol with cyclohexanone in the top of the tower to a crude alcohol ketone tank, discharging kettle liquid, and returning a side line to the crude alcohol tank; and the separation of the intermediate components is completed by means of decompression and normal pressure rectification. However, when the content of the intermediate component in the crude alcohol tank is not high, the intermediate component is difficult to separate in the two ways, and the economic benefit brought by the method is considerable only when the content of the intermediate component in the system is accumulated to a certain extent, but the continuous operation can add extra energy consumption to the production process of the device.

As shown by the analysis, aiming at the alcohol-ketone separation process, the energy consumption of the light-component removal step is maximum, but the energy consumption can be obviously reduced by a few methods. Although some solutions have been proposed in recent years for the accumulation of intermediate impurities in the recycle cyclohexanol, good separation effect can be achieved only when intermediate impurities accumulate to a certain level in the system by intermittent operation, it is difficult to control it to a low level, and stable operation of the apparatus is not facilitated, and additional energy consumption is also increased, which is not advantageous in reducing the energy consumption in the refining process of cyclohexanone.

Disclosure of Invention

The invention aims to provide a cyclohexanone refining device and a cyclohexanone refining method which can greatly reduce the energy consumption and equipment investment of the device and improve the utilization rate of raw materials and the yield of products.

In order to achieve the above object, the present invention provides a cyclohexanone refining apparatus comprising:

a separation unit of a partition tower, which is used for processing a crude alcohol ketone material prepared by cyclohexanol dehydrogenation reaction to prepare a refined alcohol ketone mixture; the divided wall column separation unit includes a divided wall column in which,

the separation wall tower is internally provided with a separation wall, the separation wall divides the separation wall tower into a prefractionation area, an alcohol ketone refining area, a light impurity separation area and a heavy impurity separation area, and the prefractionation area and the alcohol ketone refining area are positioned at two sides of the separation wall; the prefractionation area is communicated with the crude alcohol ketone feed inlet and is used for inputting the crude alcohol ketone material into the prefractionation area of the dividing wall column; the light impurity separation zone is positioned at the top of the partition tower and is used for enriching light impurities in the crude alcohol ketone material; the heavy impurity separation zone is positioned at the tower kettle part of the partition tower and is used for enriching heavy impurities in the crude alcohol ketone material; the alcohol ketone refining zone is used for preparing refined alcohol ketone mixture, and a discharging hole of the refined alcohol ketone mixture is communicated with the alcohol ketone refining zone and is used for discharging the refined alcohol ketone mixture prepared by the partition tower;

A ketone refining unit for separating refined alcohol-ketone mixture prepared by the bulkhead tower to obtain refined ketone and cyclic alcohol of the ketone tower; the ketone refining unit comprises:

the ketone tower is provided with a refined alcohol ketone mixture feed inlet, a refined ketone discharge outlet and a circulating alcohol discharge outlet; wherein, the refined alcohol ketone mixture feed inlet is communicated with the refined alcohol ketone mixture discharge outlet of the partition tower and is used for leading the refined alcohol ketone mixture to enter the ketone tower; the refined ketone discharge port is used for discharging refined ketone, and the circulating alcohol discharge port is used for discharging circulating alcohol of the ketone tower.

The cyclohexanone refining apparatus as described above, further comprising: the dehydrogenation reaction unit is used for carrying out dehydrogenation reaction on the cyclohexanol material to obtain the crude alcohol ketone material;

the dehydrogenation reaction unit is provided with a feed inlet for inputting cyclohexanol materials and a crude alcohol ketone discharge outlet for discharging crude alcohol ketone materials, and the crude alcohol ketone discharge outlet is communicated with the crude alcohol ketone feed inlet of the partition tower and is used for inputting the crude alcohol ketone materials prepared by the dehydrogenation reaction unit into the partition tower;

the circulating alcohol outlet of the ketone tower is communicated with one feed inlet of the dehydrogenation reaction unit, so that ketone tower circulating alcohol materials from the ketone tower are circulated back to the dehydrogenation reaction unit.

The cyclohexanone refining device, wherein the partition tower is also provided with a fusel-containing discharging port for enriching intermediate accumulated impurities, and the fusel-containing discharging port is used for discharging fusel-containing materials enriched with intermediate accumulated impurities from the partition tower;

the cyclohexanone refining apparatus further comprises an alcohol refining unit, wherein the circulating alcohol refining unit comprises:

an alcohol tower provided with one or more feed inlets, a circulating alcohol discharge outlet arranged at the top of the tower, and an accumulated impurity outlet arranged in the middle of the tower kettle; the impurity-containing alcohol discharge port of the partition tower, which is used for enriching the intermediate accumulated impurities, is communicated with one feed port of the alcohol tower, so that impurity-containing alcohol materials from the partition tower, which are used for enriching the intermediate accumulated impurities, enter the alcohol tower for treatment, and the circulating alcohol materials of the alcohol tower are obtained; the circulating alcohol discharge port of the alcohol tower is communicated with one feed port of the dehydrogenation reaction unit, so that the circulating alcohol material of the alcohol tower from the alcohol tower is circulated back to the dehydrogenation reaction unit.

The cyclohexanone refining apparatus as described above wherein said alcohol column is further provided with a cyclohexanol feed inlet such that at least a portion of fresh cyclohexanol feed enters said alcohol column for treatment.

The cyclohexanone refining apparatus as described above wherein the cyclohexanone refining apparatus further comprises an alcohol column top-ketone column bottom heat exchanger for heat exchanging column top material from an alcohol column top with column bottom material from a ketone column bottom in the alcohol column top-ketone column bottom heat exchanger.

The cyclohexanone refining device, wherein the operating pressure of the alcohol tower is 101-200kPa, the reflux ratio is 0.1-10, the tower top temperature is 80-190 ℃, and the tower bottom temperature is 180-250 ℃.

The cyclohexanone refining device, wherein the operation pressure of the partition tower is 1-90kPa, the reflux ratio is 10-800, the tower top temperature is 80-150 ℃, the tower bottom temperature is 130-180 ℃, and the total theoretical plates of the tower are 30-100;

wherein the theoretical plate number of the prefractionation area is 5-50, and the cross section area of the prefractionation area is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining area is 15-70; the theoretical plate number of the light impurity separation zone is 5-30; the theoretical plate number of the heavy impurity separation zone is 5-30; the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1.

The cyclohexanone refining device, wherein the operation pressure of the ketone tower is 1-60kPa, the reflux ratio is 0.5-10, the tower top temperature is 35-100 ℃, and the tower bottom temperature is 50-150 ℃.

The cyclohexanone refining device as described above, wherein the crude alcohol ketone material has a cyclohexanol content of 30 to 70%, a cyclohexanone content of 25 to 70%, a light impurity content of 0.1 to 10%, a heavy impurity content of 0.1 to 10%, and an intermediate accumulated impurity content of 0.1 to 25% based on the total weight of the crude alcohol ketone material.

The embodiment of the invention also provides a cyclohexanone refining method, which is carried out in the cyclohexanone refining device and comprises the following steps:

allowing a crude alcohol ketone material prepared by cyclohexanol dehydrogenation to enter a prefractionation area of a bulkhead tower through a crude alcohol ketone feed inlet of the bulkhead tower for treatment, preparing a refined alcohol ketone mixture in an alcohol ketone refining area of the bulkhead tower, and discharging the refined alcohol ketone mixture out of the bulkhead tower through a refined alcohol ketone mixture discharge outlet;

enabling the refined alcohol-ketone mixture to enter a ketone tower through a refined alcohol-ketone mixture feed inlet of the ketone tower for refining, obtaining a refined ketone product at the top of the ketone tower, and extracting from a refined ketone discharge outlet of the ketone tower; and (3) obtaining a ketone tower circulating alcohol material at the tower kettle of the ketone tower, and extracting the ketone tower circulating alcohol material from a circulating alcohol discharge port of the ketone tower.

The method for refining cyclohexanone as described above, further comprising:

feeding the cyclohexanol material into a dehydrogenation reaction unit through a feed inlet to perform cyclohexanol dehydrogenation reaction to obtain a crude alcohol ketone material, and discharging the crude alcohol ketone material through a crude alcohol ketone discharge outlet;

a ketone column recycle alcohol feed from the ketone column is recycled back to the dehydrogenation reaction unit.

The method for refining cyclohexanone in the specific embodiment further comprises the following steps: discharging a fusel-containing material enriched in intermediate accumulated impurities from a side line of a heavy impurity separation zone of the dividing wall column;

enabling the impurity-containing alcohol material enriched with the intermediate accumulated impurities from the partition tower to enter an alcohol tower for treatment to obtain an alcohol tower circulating alcohol material;

recycling alcohol column recycle alcohol material from the alcohol column back to the dehydrogenation reaction unit.

The cyclohexanone refining method, wherein the mass ratio of the refined alcohol ketone mixture to the impurity-containing alcohol material enriched with intermediate accumulated impurities is 3-10:1; and/or

The sum of the ketone column recycle alcohol material and the alcohol column recycle alcohol material is 0.01 to 0.99 mass percent of the cyclohexanol material fed to the dehydrogenation reaction unit.

The method for refining cyclohexanone as described above, further comprising:

at least a portion of the fresh cyclohexanol feed is passed to the alcohol column for treatment.

The cyclohexanone refining method, wherein the operating pressure of the alcohol tower is 101-200kPa, the reflux ratio is 0.1-10, the tower top temperature is 80-190 ℃, and the tower bottom temperature is 180-250 ℃.

The operation pressure of the partition tower is 1-90kPa, the reflux ratio is 10-800, the tower top temperature is 80-150 ℃, the tower bottom temperature is 130-180 ℃, and the total theoretical plates of the tower are 30-100;

wherein the theoretical plate number of the prefractionation area is 5-50, and the cross section area of the prefractionation area is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining area is 15-70; the theoretical plate number of the light impurity separation zone is 5-30; the theoretical plate number of the heavy impurity separation zone is 5-30; the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1;

the operation pressure of the ketone tower is 1-60kPa, the reflux ratio is 0.5-10, the tower top temperature is 35-100 ℃, and the tower bottom temperature is 50-150 ℃.

Compared with the prior art, the technical scheme has the following advantages: by arranging the partition tower, the coupling of the processes of light removal and heavy impurity removal is realized in a single tower by utilizing the partition tower technology, the separation characteristics of the partition tower are fully utilized, and the refined alcohol-ketone mixture with high purity is obtained, so that the product yield is improved, the cyclohexanone content in the circulating alcohol is obviously reduced, and the equipment investment and the energy consumption are saved; the recycle alcohol refining unit is arranged, so that recycle alcohol is separated from the impurity-containing alcohol material enriched with intermediate accumulated impurities, which is separated by the partition tower separating unit, the utilization rate of cyclohexanol materials is improved, and accumulation of intermediate accumulated impurities is avoided; by arranging the heat exchanger of the alcohol tower top and the ketone tower kettle, the heat of the alcohol tower can be coupled with the operation of the ketone tower, and the energy consumption is not increased even if the alcohol tower is increased.

Drawings

The following drawings are only for purposes of illustration and explanation of the present invention and are not intended to limit the scope of the invention. Wherein:

FIG. 1 is a schematic view of an embodiment of a cyclohexanone refining apparatus of the invention;

FIG. 2 is a schematic view of another embodiment of the cyclohexanone refining apparatus of the invention;

FIG. 3 is a schematic diagram of a device of a comparative example;

fig. 4 is a schematic view of another comparative example apparatus.

Detailed Description

The present application is further described in detail below by way of the accompanying drawings and examples. The features and advantages of the present application will become more apparent from the description.

The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are illustrated in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

In addition, the technical features described below in the different embodiments of the present application may be combined with each other as long as they do not collide with each other.

As shown in fig. 1 and 2, the cyclohexanone refining apparatus provided herein may include a dehydrogenation reaction unit 100, where the dehydrogenation reaction unit 100 is configured to subject a cyclohexanol material to dehydrogenation treatment in the presence of a catalyst to obtain a crude alcohol ketone material 104. The cyclohexanol feed 102 fed to dehydrogenation reaction unit 100 can be fresh cyclohexanol feed 101 and can further comprise an amount of recycle alcohol feed 136 (comprising ketone column recycle alcohol feed 127 and optionally alcohol column recycle alcohol feed 133), as described below. The hydrogen 105 generated by the dehydrogenation unit 100 is discharged through a pipeline, and the obtained crude alcohol ketone material 104 enters a subsequent separation unit 200 of a partition tower for separation treatment. As will be described later, a part of the fresh cyclohexanol feedstock 103 may also be fed into the alcohol tower 16 for treatment, so that the fresh cyclohexanol feedstock can be previously removed of intermediate accumulated impurities that are difficult to remove under reduced pressure, before being fed into the dehydrogenation reaction unit 100, avoiding accumulation of intermediate accumulated impurities in the reaction system.

The dehydrogenation unit 100 and the dehydrogenation reactions occurring therein can employ reactors and reaction conditions known in the art. For example, the temperature may be 200 to 280℃and the pressure 0 to 50kPag. The catalyst used may also be various catalysts known in the art and will not be described in detail herein.

In one embodiment, the crude alcohol ketone material 104 has a cyclohexanol content of 30 to 70%, cyclohexanone content of 25 to 70%, light impurity content of 0.1 to 10%, and heavy impurity content of 0.1 to 10%, based on the total weight of the crude alcohol ketone material 104.

The cyclohexanone purification apparatus provided herein may include a divided wall column separation unit 200 for processing a crude alcohol ketone material 104 produced from a cyclohexanol dehydrogenation reaction to produce a purified alcohol ketone mixture 121. As shown in fig. 1 and 2, the divided wall column separation unit 200 includes a divided wall column 8, a divided wall column top condenser 9, a divided wall column top reflux drum 10, and a divided wall column bottom reboiler 11.

A partition wall 1 is arranged in the partition wall tower 8, the partition wall 1 divides the partition wall tower 8 into a prefractionation area 3, an alcohol ketone refining area 4, a light impurity separation area 2 and a heavy impurity separation area 5, and the prefractionation area 3 and the alcohol ketone refining area 4 are positioned at two sides of the partition wall 1. The partition wall 1 can be arranged in the middle of the partition wall tower 8, a light impurity separation zone 2 is arranged above the partition wall 1, a heavy impurity separation zone 5 is arranged below the partition wall 1, a prefractionation zone 3 is arranged in a zone, connected with a feed pipeline, of one side of the partition wall 1, and an alcohol ketone refining zone 4 is arranged in a zone, connected with a discharge pipeline, of the other side of the partition wall 1. The partition tower 8 is internally provided with a crude alcohol ketone feed inlet and a refined alcohol ketone mixture discharge outlet, and the prefractionation area 3 is communicated with the crude alcohol ketone feed inlet and is used for inputting the crude alcohol ketone material 104 into the prefractionation area 3 of the partition tower 8; the light impurity separation zone 2 is positioned at the top part of the partition tower 8 and is used for enriching light impurities in the crude alcohol ketone material; the heavy impurity separation zone 5 is positioned at the tower kettle part of the partition tower 8 and is used for enriching heavy impurities in the crude alcohol ketone material; the alcohol ketone refining zone 4 is used for preparing a refined alcohol ketone mixture, and a discharge hole of the refined alcohol ketone mixture is communicated with the alcohol ketone refining zone 4 and is used for discharging a refined alcohol ketone mixture 121 prepared by the partition tower 8.

In one embodiment, the number of full column theoretical plates of divided wall column 8 is 30 to 100; wherein the theoretical plate number of the prefractionation area 3 is 5-50, and the cross section area of the prefractionation area 3 is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining zone 4 is 15-70; the theoretical plate number of the light impurity separation zone 2 is 5-30; the number of theoretical plates of the heavy impurity separation zone 5 is 5 to 30.

A dividing wall column top condenser 9 and a dividing wall column top reflux drum 10 are connected to the light impurity separation region 2 of the dividing wall column 8, and are used for extracting the light impurities 114, 119,118 enriched in the light impurity separation region 2. The overhead material 115 from the divided wall column exiting the light impurity separation zone 2 may be in the vapor phase and the liquid phase stream 116 after condensation by the divided wall column overhead condenser 9 enters the divided wall column overhead reflux drum 10, a portion of stream 117 is refluxed to the top of the divided wall column 2, and light impurities 118, 119, 114 may be withdrawn from the divided wall column overhead reflux drum 10. In one embodiment, the overhead temperature is 80-150 ℃, and the overhead reflux ratio is 50-300:1

The dividing wall column bottoms reboiler 11 is used for heating the column bottoms of the dividing wall column, so that a part of the column bottoms 120 is reboiled and then flows back into the dividing wall column, and a part of the heavy impurities 128 enriched in the heavy impurity separation zone 5 are extracted from the dividing wall column 8. In one embodiment, the bottoms temperature is 130-180deg.C and the bottoms reflux ratio is 150-500:1.

In the application, the crude alcohol ketone material 104 is firstly subjected to preliminary separation in a prefractionation area 3 of a partition tower 8, light impurities in the crude alcohol ketone are enriched in a light impurity separation area 2, and finally light impurities 118, 119 and 114 are extracted after passing through a partition tower top condenser 9 and a partition tower top reflux tank 10; the heavy impurities are enriched in the heavy impurity separation zone 5, and the heavy impurities 128 are extracted from the tower bottom of the dividing wall tower; the alcohol ketone refining zone 4 of the divided wall column 8 produces a refined alcohol ketone mixture 121.

In one embodiment, the operation pressure of the partition tower is 1-90kPa, the reflux ratio is 10-800, the tower top temperature is 80-150 ℃, and the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1.

In one embodiment, as shown in fig. 2, a side line of the heavy impurity separation zone 5 of the dividing wall column 8 is further provided with a fusel-containing discharge port for extracting a fusel-containing material 129 enriched in intermediate accumulated impurities. In one embodiment, the mass ratio of refined alcohol-ketone mixture 121 to the impurity-containing alcohol-enriched material 129 enriched in intermediate accumulated impurities is in the range of 3 to 10:1. By withdrawing a portion of the fusel-containing material 129 enriched in intermediate accumulated impurities, the accumulation of intermediate accumulated impurities can be reduced, facilitating the subsequent refining process and facilitating an increase in purity of the product. This fusel-containing material 129 may be passed to a subsequent alcohol column 16 for processing as described below.

Such an arrangement is particularly advantageous when the crude alcohol ketone material 104 contains some intermediate accumulated impurities. In one embodiment, the crude alcohol ketone material 104 has a cyclohexanol content of 30-70%, cyclohexanone content of 25-70%, light impurity content of 0.1-10%, heavy impurity content of 0.1-10%, and intermediate cumulative impurity content of 0.1-25% based on the total weight of the crude alcohol ketone material.

The apparatus of the present application comprises a ketone refining unit 300 for separating a refined alcohol ketone mixture 121 produced in a divided wall column 8 to obtain refined ketone 125 and recycled alcohol 127. The ketone refining unit 300 includes a ketone column 12, a ketone column top condenser 13, a ketone column top reflux drum 14, and a ketone column bottom reboiler 20. Refined alcohol ketone mixture 121 enters ketone column 12 from the middle, refined ketone product 125 at the top of the column can be taken out as product, refined recycle alcohol 127 at the bottom of the column is taken out from the bottom of the column, and can be directly recycled back to dehydrogenation reaction unit 100 as part of the alcohol feed for further reaction.

A ketone column top condenser 13, a ketone column top reflux drum 14 are connected to the top portion of the ketone column 12 for withdrawing a refined ketone product 125. The overhead ketone stream 122 exiting the top of ketone 12 may be in the vapor phase, and the liquid phase stream 123 after condensation by the overhead ketone condenser 13 may enter the overhead ketone reflux drum 14, and a portion of stream 124 may be refluxed to the top of ketone 12, and refined ketone product 125 may be withdrawn from the overhead ketone reflux drum 14. In one embodiment, the overhead temperature is from 35 to 100 ℃, and the overhead reflux ratio is from 1.0 to 3.5:1. in one embodiment, cyclohexanone content in refined ketone product 125 may be up to about 100%.

The ketone column bottoms reboiler 20 is used to heat the bottoms material of the ketone column such that a portion of the bottoms material 126 is reboiled and refluxed to the ketone column 12 and a portion of the ketone column recycle alcohol 127 containing a small amount of ketone is withdrawn at the ketone column bottoms. In one embodiment, the temperature of the tower kettle is 50-150 ℃, and the reflux ratio of the tower kettle is 2.0-5.0:1. in one embodiment, the ketone column recycle alcohol 127 has a cyclohexanol content of from 99.0 to 99.8% and a cyclohexanone content of from 0.2 to 1.0% based upon the total weight of ketone column recycle alcohol 127.

In one embodiment, the ketone column 12 is operated at a pressure of 1 to 60kPa, a reflux ratio of 0.5 to 10, a column top temperature of 35 to 100 ℃, and a column bottom temperature of 50 to 150 ℃.

As shown in fig. 2, the cyclohexanone refining apparatus of the present application may further comprise an alcohol refining unit 400 for treating the fusel-containing material 129 as well as a portion of the fresh cyclohexanol feedstock 103. The alcohol refining unit 400 includes an alcohol column 16, an alcohol column top-ketone column bottoms heat exchanger 20, an alcohol column top reflux drum 18, and an alcohol column bottoms reboiler 19. In one embodiment, a portion of the fresh cyclohexanol feedstock 103 fed to the alcohol refining unit 400 may comprise 10-50wt% of total fresh cyclohexanol feedstock 101.

The impurity-containing alcohol material 129 enriched with intermediate accumulated impurities and a part of fresh cyclohexanol raw material 103 enter an alcohol tower 16 to separate intermediate accumulated impurities, a tower top gas phase material 130 of the alcohol tower enters an alcohol tower top-ketone tower kettle heat exchanger 20, a condensed liquid phase flow 131 enters an alcohol tower top reflux tank 18, a part of the material 132 returns to the alcohol tower 16 as reflux, the other part of the material is extracted as alcohol tower circulating alcohol 133, and the material is mixed with ketone tower circulating alcohol 127 and then returns to a dehydrogenation reaction unit as a total circulating alcohol flow 136 for further reaction.

An alcohol tower top-ketone tower kettle heat exchanger 20 is arranged and is used for enabling tower top materials 130 from the alcohol tower top and tower kettle materials 126 from the ketone tower kettle to exchange heat in the alcohol tower top-ketone tower kettle heat exchanger, and the temperature of an alcohol tower top material flow is higher than the temperature of the ketone tower kettle materials by more than 10 ℃, so that heat exchange is realized in the alcohol tower top-ketone tower kettle heat exchanger 20, heat coupling of the alcohol tower top material and the ketone tower kettle material is realized, and energy consumption is reduced. In one embodiment, the overhead temperature is 80-190 ℃ and the reflux ratio of the tower bottom is 2.0-5.0:1.

in one embodiment, the mass ratio of the recycle alcohol material (sum of the alcohol column recycle alcohol 133 and ketone column recycle alcohol 127) to the cyclohexanol material entering the dehydrogenation reaction unit 100 may be in the range of 0.01 to 0.99.

The alcohol column bottoms reboiler 19 is used to heat the bottoms material of the alcohol column such that a portion of the bottoms material 132 is reboiled back into the alcohol column 16 and a portion of the intermediate accumulated impurity stream 135 is withdrawn at the alcohol column bottoms. In one embodiment, the temperature of the tower kettle is 180-250 ℃, and the reflux ratio of the tower kettle is 250-450:1.

in one embodiment, the alcohol column 16 may be operated at atmospheric pressure at an operating pressure of 101 to 200kPa, a reflux ratio of 0.1 to 10, a column top temperature of 80 to 190 ℃, and a column bottom temperature of 180 to 250 ℃.

The recycle alcohol refining unit can be selectively arranged according to different process production conditions. For example, for a process with less intermediate cumulative impurity content, the recycle alcohol refining unit may not be provided; for the process with more impurities and serious accumulation phenomenon in the oxidation method, the circulating alcohol refining unit is arranged to remove the intermediate accumulated impurities, so that the method can be flexibly applied to cyclohexanone preparation flows of different processes.

Thus, the present application provides a method for purifying cyclohexanone, which can be performed in the above-mentioned cyclohexanone purifying apparatus, comprising:

treating a crude alcohol ketone material prepared by cyclohexanol dehydrogenation through a bulkhead tower, preparing a refined alcohol ketone mixture in an alcohol ketone refining area of the bulkhead tower, and discharging the refined alcohol ketone mixture out of the bulkhead tower through a refined alcohol ketone mixture discharging port;

Enabling the refined alcohol-ketone mixture to enter a ketone tower through a refined alcohol-ketone mixture feed inlet of the ketone tower for refining, obtaining a refined ketone product at the top of the ketone tower, and extracting from a refined ketone discharge outlet of the ketone tower; and (3) obtaining a ketone tower circulating alcohol material at the tower kettle of the ketone tower, and extracting the ketone tower circulating alcohol material from a circulating alcohol discharge port of the ketone tower.

In one embodiment, the method of the present application further comprises: feeding the cyclohexanol material into a dehydrogenation reaction unit through a feed inlet to perform cyclohexanol dehydrogenation reaction to obtain a crude alcohol ketone material, and discharging the crude alcohol ketone material through a crude alcohol ketone discharge outlet;

a ketone column recycle alcohol feed from the ketone column is recycled back to the dehydrogenation reaction unit.

In one embodiment, the method of the present application further comprises:

discharging a fusel-containing material enriched in intermediate accumulated impurities from a side line of a heavy impurity separation zone of the dividing wall column;

enabling the impurity-containing alcohol material enriched with the intermediate accumulated impurities from the partition tower to enter an alcohol tower for treatment to obtain an alcohol tower circulating alcohol material;

recycling alcohol column recycle alcohol material from the alcohol column back to the dehydrogenation reaction unit.

In one embodiment, the mass ratio of the refined alcohol ketone mixture to the fusel-containing material enriched in intermediate accumulated impurities is 3-10:1; and/or

The sum of the ketone column recycle alcohol material and the alcohol column recycle alcohol material is 0.01 to 0.99 mass percent of the cyclohexanol material fed to the dehydrogenation reaction unit.

In one embodiment, the method of the present application further comprises:

at least a portion of the fresh cyclohexanol feed is passed to the alcohol column for treatment.

In one embodiment, the alcohol column is operated at a pressure of 101 to 200kPa, a reflux ratio of 0.1 to 10, a column top temperature of 80 to 190 ℃, and a column bottom temperature of 180 to 250 ℃.

In one embodiment, the operation pressure of the partition tower is 1-90kPa, the reflux ratio is 10-800, the tower top temperature is 80-150 ℃, the tower bottom temperature is 130-180 ℃, and the total theoretical plates of the tower are 30-100;

wherein the theoretical plate number of the prefractionation area is 5-50, and the cross section area of the prefractionation area is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining area is 15-70; the theoretical plate number of the light impurity separation zone is 5-30; the theoretical plate number of the heavy impurity separation zone is 5-30; the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1;

The operation pressure of the ketone tower is 1-60kPa, the reflux ratio is 0.5-10, the tower top temperature is 35-100 ℃, and the tower bottom temperature is 50-150 ℃.

As described above, the ketone column recycle alcohol and the alcohol column recycle alcohol are also recycled back to the dehydrogenation reaction unit for further reaction. It should be noted that the description of the related embodiments of the apparatus is equally applicable to the method, and will not be repeated here.

In the present application, light impurities refer to substances having a boiling point lower than that of cyclohexanone under vacuum conditions (1 to 90 kPa), including but not limited to: water, alcohols such as ethanol, propanol, n-isobutanol, n-iso-neopentyl alcohol and cyclopentanol, aldehydes such as acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde and cycloalkylaldehyde, ketones such as acetone, butanone, pentanone, alkyl cyclopentanone and cycloalkyl ketone, cyclohexyl ethers such as methyl cyclohexyl ether, ethyl cyclohexyl ether and butyl cyclohexyl ether, olefins such as ethylene, propylene, butene, cyclohexene and cyclopentene, esters such as ethyl acetate and butyl acetate, ketenes such as cyclopentenone and cyclohexenone, epoxy groups such as ethylene oxide, propylene oxide and epoxycyclohexane, and low-carbon fatty acids such as acetic acid, propionic acid and butyric acid.

Heavy impurities refer to materials having a boiling point higher than the boiling point of cyclohexanol under vacuum conditions (1-90 kPa), including but not limited to: alkyl cyclohexanols such as ethylcyclohexanol, propylcyclohexanol, cyclopentylcyclohexanol and cyclohexylcyclohexanol, alkyl cyclohexanones such as methylcyclohexanone, ethylcyclohexanone, propylcyclohexanone and butylcyclohexanone, alkylphenols such as phenol, cresol and ethylphenol, and alcohol ketone condensates such as cyclohexylcyclohexanone and cyclohexylcyclohexanol.

Intermediate accumulated impurities refer to materials having a boiling point close to (within + -10 ℃ from) the boiling point of cyclohexanol under vacuum conditions (1-90 kPa), but a boiling point higher than that of cyclohexanol under normal pressure or pressurized conditions, including but not limited to: ethylcyclohexanone, cyclohexylketone, cyclohexyl acetate, and the like.

The method adopts a partition tower to separate light impurities and heavy impurities, adopts a ketone tower to separate cyclohexanol to obtain qualified cyclohexanone products, and optionally further adopts an alcohol tower to separate intermediate accumulated impurities in cyclohexanol, thereby obtaining cyclohexanone products with high purity. The method provided by the invention can greatly reduce the energy consumption and equipment investment of the device, improve the utilization rate of raw materials and the yield of products, can be flexibly applied to the cyclohexanone preparation flow of different processes, has simple operation flow and is easy for industrial amplification.

The method and apparatus for refining crude alcohol ketone according to the present invention will be described with reference to the accompanying drawings, but the present invention is not limited thereto.

The invention is further illustrated by the following examples, which are not intended to be limiting in any way.

Example 1

The crude alcohol ketone feed a was subjected to alcohol ketone separation using the apparatus shown in fig. 1, and the mass composition of the main materials is shown in table 1. The apparatus does not include the dehydrogenation reaction unit 100, but includes the dividing wall column separation unit 200 and the ketone column separation unit 300. Crude alcohol ketone feed a (104) is fed directly to dividing wall column 8 before being treated in ketone column 12. The operating conditions, equipment structural parameters and energy consumption of the bulkhead column and the ketone column are shown in Table 2, the liquid ratio of the light impurity separation zone to the liquid flowing into the prefractionation zone and the alcohol ketone refining zone in the bulkhead column is 0.1:0.9, and the gas ratio of the heavy impurity separation zone to the liquid flowing into the prefractionation zone and the alcohol ketone refining zone is 0.21:0.89.

Comparative example 1

The crude alcohol ketone feed a was subjected to alcohol ketone separation using the apparatus shown in fig. 3, and the main material mass composition is shown in table 1, and the operating conditions, equipment structural parameters and energy consumption of the light component removal column, ketone column and alcohol column are shown in table 2. Unlike example 1, crude alcohol ketone is passed through a light ends column, a ketone column, and an alcohol column in this order to obtain a purified ketone product and recycle alcohol.

The specific process flow is as follows: after the crude alcohol ketone 101 'enters the light component removal tower 8', the gas-phase tower top material 115 'is cooled by the light component removal tower top condenser 9' to obtain a liquid-phase material 116', and after flowing into the light component removal tower top reflux tank 10' through a pipeline, light impurities 119 'and 118' are removed, and the rest 117 'is refluxed to the light component removal tower 8'. Part of the liquid phase material 120' at the tower bottom of the light component removing tower is heated by the reboiler 11' at the tower bottom of the light component removing tower, and then flows back to the light component removing tower 8', the other part is taken as an alcohol-ketone mixture 121' and enters the ketone tower 12' from the middle part, the refined ketone product 125' at the tower top can be taken out as a product, and the circulating alcohol 127' at the tower bottom is taken out from the tower bottom. Specifically, a ketone column top condenser 13', a ketone column top reflux drum 14', is connected to the top portion of the ketone column 12 'for producing a refined ketone product 125'. The overhead ketone stream 122' exiting the top of ketone column 12' may be in the vapor phase, and the liquid phase stream 123' after condensation by ketone column overhead condenser 13' may enter ketone column overhead reflux drum 14', and a portion of stream 124' may be refluxed to the top of ketone column 12', and refined ketone product 125' may be withdrawn from ketone column overhead reflux drum 14 '. The ketone column bottoms reboiler 15 'is used to heat the bottoms material of the ketone column such that a portion of the bottoms material 126' is reboiled and returned to the ketone column 12 'and a portion of the ketone column recycle alcohol 127' containing a small amount of ketone is withdrawn at the ketone column bottoms. After the ketone tower circulating alcohol 127' enters the alcohol tower 16', the tower top gas phase material 128' of the alcohol tower enters the ketone tower top condenser 17' for condensation, the condensed liquid phase flow 129' enters the alcohol tower top reflux tank 18', part of the material 130' returns to the alcohol tower 16' as reflux, and the other part of the material is extracted as alcohol tower circulating alcohol 131', so that the material can be recycled to the dehydrogenation reaction unit for continuous reaction. The alcohol column bottoms reboiler 19 'is used to heat the bottoms material of the alcohol column such that a portion of the bottoms material 132' is reboiled back into the alcohol column 16 'and a portion of the intermediate accumulated impurity stream 133' is withdrawn at the alcohol column bottoms.

The energy consumption of the device in the example 1 is saved by 23% compared with that in the comparative example 1, and the cyclohexanone content in the circulating alcohol can be controlled to be 0.4%.

Example 2

The crude alcohol ketone feed B was subjected to alcohol ketone separation using the apparatus shown in fig. 2, and the mass composition of the main materials is shown in table 3. The apparatus also does not include the dehydrogenation reaction unit 100, but includes a dividing wall column separation unit 200, a ketone column separation unit 300, and an alcohol column 400. Crude alcohol ketone feed B (104) is fed directly to dividing wall column 8 prior to treatment in ketone column 12 and alcohol column 16. The operating conditions, equipment structural parameters and energy consumption of the bulkhead column, the ketone column and the alcohol column are shown in Table 4, the liquid ratio of the light impurity separation zone flowing into the prefractionation zone to the alcohol ketone refining zone in the bulkhead column is 0.7:0.3, and the gas phase ratio of the heavy impurity separation zone flowing into the prefractionation zone to the alcohol ketone refining zone is 0.81:0.19.

Comparative example 2

The crude alcohol ketone feed B was subjected to alcohol ketone separation using the apparatus shown in FIG. 3, and the main material mass composition is shown in Table 3, and the operating conditions, equipment structural parameters and energy consumption of the light component removal column, ketone column and alcohol column are shown in Table 4. Unlike example 2, crude alcohol ketone is passed through a light ends column, a ketone column, and an alcohol column in this order to obtain a purified ketone product and recycle alcohol. The specific process flow was similar to comparative example 1.

The energy consumption of the device in the example 2 is 15% less than that in the comparative example 2, and the cyclohexanone content in the circulating alcohol can be controlled to be 0.4%.

Example 3

The device shown in fig. 2 is adopted to carry out dehydrogenation reaction and alcohol ketone separation on the cyclohexanol raw material C, the mass composition of main materials is shown in table 5, the operating conditions, equipment structural parameters and energy consumption of a partition tower, a ketone tower and an alcohol tower are shown in table 6, part of the cyclohexanol raw material directly enters the alcohol tower, the proportion of the cyclohexanol raw material is controlled to be 25% of the total feeding amount of the hexanol raw material, the ratio of liquid flowing into the prefractionation area from the light impurity separation area to the alcohol ketone refining area in the partition tower is 0.17:0.83, and the gas phase ratio of liquid flowing into the prefractionation area from the heavy impurity separation area to the alcohol ketone refining area is 0.3:0.7.

Comparative example 3

The device shown in fig. 4 is used for dehydrogenation reaction of cyclohexanol raw material C and separation of alcohol and ketone, the mass composition of main materials is shown in table 5, and the operating conditions, equipment structural parameters and energy consumption of the light component removal tower, ketone tower and alcohol tower are shown in table 6. Unlike example 3, the content of intermediate accumulated impurities in the recycle alcohol was not separated, and the accumulation of intermediate accumulated impurities was further exacerbated as the recycle alcohol was returned to the reaction unit.

The specific process flow is as follows: after mixing the cyclohexanol raw material 101 'and alcohol tower circulating alcohol 131', introducing the mixture into a dehydrogenation reaction unit by using mixed alcohol feed 103 'to perform dehydrogenation treatment to obtain a crude alcohol ketone material 104'; the crude alcohol ketone material 104 'enters the light component removal tower 8', the gas phase tower top material 115 'is cooled by the light component removal tower top condenser 9', a liquid phase material 116 'is obtained, after flowing into the light component removal tower top reflux tank 10' through a pipeline, light impurities 119 'and 118' are removed, and the residual 117 'is refluxed to the light component removal tower 8'. Part of the liquid phase material 120' at the tower bottom of the light component removing tower is heated by the reboiler 11' at the tower bottom of the light component removing tower, and then flows back to the light component removing tower 8', the other part is taken as an alcohol-ketone mixture 121' and enters the ketone tower 12' from the middle part, the refined ketone product 125' at the tower top can be taken out as a product, and the ketone tower circulating alcohol 127' at the tower bottom is taken out from the tower bottom. Specifically, a ketone column top condenser 13', a ketone column top reflux drum 14', is connected to the top portion of the ketone column 12 'for producing a refined ketone product 125'. The overhead ketone stream 122' exiting the top of ketone column 12' may be in the vapor phase, and the liquid phase stream 123' after condensation by ketone column overhead condenser 13' may enter ketone column overhead reflux drum 14', and a portion of stream 124' may be refluxed to the top of ketone column 12', and refined ketone product 125' may be withdrawn from ketone column overhead reflux drum 14 '. The ketone column bottoms reboiler 15 'is used to heat the bottoms material of the ketone column such that a portion of the bottoms material 126' is reboiled and returned to the ketone column 12 'and a portion of the ketone column recycle alcohol 127' containing a small amount of ketone is withdrawn at the ketone column bottoms. After the ketone tower circulating alcohol 127 'enters the alcohol tower 16', the tower top gas phase material 128 'of the alcohol tower enters the ketone tower top condenser 17' for condensation, the condensed liquid phase flow 129 'enters the alcohol tower top reflux tank 18', part of the material 130 'returns to the alcohol tower 16' as reflux, the other part of the material is extracted as alcohol tower circulating alcohol 131', and the alcohol tower circulating alcohol 131' returns to the dehydrogenation reaction unit for continuous reaction. The alcohol column bottoms reboiler 19 'is used to heat the bottoms material of the alcohol column such that a portion of the bottoms material 132' is reboiled back into the alcohol column 16 'and a portion of the intermediate accumulated impurity stream 133' is withdrawn at the alcohol column bottoms.

The energy consumption of the device in the example 3 is reduced by 19% compared with that in the comparative example 3, and the content of intermediate impurities in the cyclohexanol feed of the reaction unit can be stably controlled at 0.3%.

Example 4

The device shown in fig. 2 is used for carrying out dehydrogenation reaction and alcohol ketone separation on cyclohexanol raw material D, the mass composition of main materials is shown in table 7, the operating conditions, equipment structural parameters and energy consumption of a partition tower, a ketone tower and an alcohol tower are shown in table 6, the proportion of partial raw material cyclohexanol directly passing through the alcohol tower is controlled to be 35% of the feeding amount, the liquid ratio of the liquid flowing into the prefractionation area from the light impurity separation area to the alcohol ketone refining area in the partition tower is 0.27:0.73, and the gas phase ratio of the liquid flowing into the prefractionation area from the heavy impurity separation area to the alcohol ketone refining area is 0.2:0.8.

Comparative example 4

The device shown in fig. 4 is used for carrying out dehydrogenation reaction on cyclohexanol raw material D and separating alcohol and ketone, the process flow is similar to that of comparative example 3, the mass composition of main materials is shown in table 7, and the operating conditions, equipment structural parameters and energy consumption of the light component removal tower, ketone tower and alcohol tower are shown in table 8. Unlike example 4, the content of intermediate accumulated impurities in the recycle alcohol was not separated, and the phenomenon of intermediate impurity accumulation was further exacerbated as the recycle alcohol was returned to the reaction unit. The specific process flow was similar to comparative example 3.

The energy consumption of the device in the example 4 is 14% less than that in the comparative example 4, and the content of the intermediate impurity in the cyclohexanol feed of the reaction unit can be stably controlled to be 0.1%.

In the description of the present application, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly, unless explicitly specified and limited otherwise. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

The present application has been described in connection with the preferred embodiments, but these embodiments are merely exemplary and serve only as illustrations. On the basis of this, many alternatives and improvements can be made to the present application, which fall within the scope of protection of the present application.

TABLE 1 Main Material composition of example 1 and comparative example 1

Table 2 example 1 and comparative example 1 plant parameters and energy consumption comparison

TABLE 3 Main Material composition of example 2 and comparative example 2

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Table 4 comparative example 2 and example 2 equipment parameters and energy consumption comparison

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TABLE 6 comparative examples 3 and 3 equipment parameters and energy consumption comparison

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Table 8 example 4 and comparative example 4 equipment parameters and energy consumption vs

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Claims (16)

1. A cyclohexanone refining apparatus, comprising:

a separation unit of a partition tower, which is used for processing a crude alcohol ketone material prepared by cyclohexanol dehydrogenation reaction to prepare a refined alcohol ketone mixture; the divided wall column separation unit includes a divided wall column in which,

The separation wall tower is internally provided with a separation wall, the separation wall divides the separation wall tower into a prefractionation area, an alcohol ketone refining area, a light impurity separation area and a heavy impurity separation area, and the prefractionation area and the alcohol ketone refining area are positioned at two sides of the separation wall; the prefractionation area is communicated with the crude alcohol ketone feed inlet and is used for inputting the crude alcohol ketone material into the prefractionation area of the dividing wall column; the light impurity separation zone is positioned at the top of the partition tower and is used for enriching light impurities in the crude alcohol ketone material; the heavy impurity separation zone is positioned at the tower kettle part of the partition tower and is used for enriching heavy impurities in the crude alcohol ketone material; the alcohol ketone refining zone is used for preparing refined alcohol ketone mixture, and a discharging hole of the refined alcohol ketone mixture is communicated with the alcohol ketone refining zone and is used for discharging the refined alcohol ketone mixture prepared by the partition tower;

a ketone refining unit for separating refined alcohol-ketone mixture prepared by the bulkhead tower to obtain refined ketone and cyclic alcohol of the ketone tower; the ketone refining unit comprises:

the ketone tower is provided with a refined alcohol ketone mixture feed inlet, a refined ketone discharge outlet and a circulating alcohol discharge outlet; wherein, the refined alcohol ketone mixture feed inlet is communicated with the refined alcohol ketone mixture discharge outlet of the partition tower and is used for leading the refined alcohol ketone mixture to enter the ketone tower; the refined ketone discharge port is used for discharging refined ketone, and the circulating alcohol discharge port is used for discharging circulating alcohol of the ketone tower.

2. The cyclohexanone refining apparatus of claim 1 further comprising: the dehydrogenation reaction unit is used for carrying out dehydrogenation reaction on the cyclohexanol material to obtain the crude alcohol ketone material;

the dehydrogenation reaction unit is provided with a feed inlet for inputting cyclohexanol materials and a crude alcohol ketone discharge outlet for discharging crude alcohol ketone materials, and the crude alcohol ketone discharge outlet is communicated with the crude alcohol ketone feed inlet of the partition tower and is used for inputting the crude alcohol ketone materials prepared by the dehydrogenation reaction unit into the partition tower;

the circulating alcohol outlet of the ketone tower is communicated with one feed inlet of the dehydrogenation reaction unit, so that ketone tower circulating alcohol materials from the ketone tower are circulated back to the dehydrogenation reaction unit.

3. A cyclohexanone refining apparatus as claimed in claim 2, wherein,

the bulkhead tower is also provided with a fusel-containing discharge port for enriching intermediate accumulated impurities, and the fusel-containing discharge port is used for discharging fusel-containing materials enriched with intermediate accumulated impurities from the bulkhead tower;

the cyclohexanone refining apparatus further comprises an alcohol refining unit, wherein the circulating alcohol refining unit comprises:

an alcohol tower provided with one or more feed inlets, a circulating alcohol discharge outlet arranged at the top of the tower, and an accumulated impurity outlet arranged in the middle of the tower kettle; the impurity-containing alcohol discharge port of the partition tower, which is used for enriching the intermediate accumulated impurities, is communicated with one feed port of the alcohol tower, so that impurity-containing alcohol materials from the partition tower, which are used for enriching the intermediate accumulated impurities, enter the alcohol tower for treatment, and the circulating alcohol materials of the alcohol tower are obtained; the circulating alcohol discharge port of the alcohol tower is communicated with one feed port of the dehydrogenation reaction unit, so that the circulating alcohol material of the alcohol tower from the alcohol tower is circulated back to the dehydrogenation reaction unit.

4. A cyclohexanone refining apparatus as claimed in claim 3, characterized in that the alcohol column is further provided with a cyclohexanol feed inlet, such that at least a portion of fresh cyclohexanol feed enters the alcohol column for treatment.

5. A cyclohexanone refining apparatus as claimed in claim 3, characterized in that the cyclohexanone refining apparatus further comprises an alcohol column top-ketone column bottom heat exchanger for heat exchanging column top material from the alcohol column top with column bottom material from the ketone column bottom in the alcohol column top-ketone column bottom heat exchanger.

6. A cyclohexanone refining apparatus as claimed in claim 3, wherein,

the operating pressure of the alcohol tower is 101-200kPa, the reflux ratio is 0.1-10, the tower top temperature is 80-190 ℃, and the tower bottom temperature is 180-250 ℃.

7. The cyclohexanone refining apparatus according to claim 1, wherein the operation pressure of the dividing wall column is 1-90kPa, the reflux ratio is 10-800, the column top temperature is 80-150 ℃, the column bottom temperature is 130-180 ℃, and the number of theoretical plates of the whole column is 30-100;

wherein the theoretical plate number of the prefractionation area is 5-50, and the cross section area of the prefractionation area is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining area is 15-70; the theoretical plate number of the light impurity separation zone is 5-30; the theoretical plate number of the heavy impurity separation zone is 5-30; the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1.

8. A cyclohexanone refining apparatus according to claim 1, characterized in that the ketone column is operated at a pressure of 1-60kPa, reflux ratio of 0.5-10, column top temperature of 35-100 ℃, column bottom temperature of 50-150 ℃.

9. A cyclohexanone refining apparatus according to claim 1, characterized in that in the crude alcohol ketone material, the cyclohexanol content is 30-70%, the cyclohexanone content is 25-70%, the light impurity content is 0.1-10%, the heavy impurity content is 0.1-10%, and the intermediate accumulated impurity content is 0.1-25% based on the total weight of the crude alcohol ketone material.

10. A cyclohexanone purification process carried out in a cyclohexanone purification device according to claim 1, comprising:

allowing a crude alcohol ketone material prepared by cyclohexanol dehydrogenation to enter a prefractionation area of a bulkhead tower through a crude alcohol ketone feed inlet of the bulkhead tower for treatment, preparing a refined alcohol ketone mixture in an alcohol ketone refining area of the bulkhead tower, and discharging the refined alcohol ketone mixture out of the bulkhead tower through a refined alcohol ketone mixture discharge outlet;

enabling the refined alcohol-ketone mixture to enter a ketone tower through a refined alcohol-ketone mixture feed inlet of the ketone tower for refining, obtaining a refined ketone product at the top of the ketone tower, and extracting from a refined ketone discharge outlet of the ketone tower; and (3) obtaining a ketone tower circulating alcohol material at the tower kettle of the ketone tower, and extracting the ketone tower circulating alcohol material from a circulating alcohol discharge port of the ketone tower.

11. The cyclohexanone refining method of claim 10 further comprising:

feeding the cyclohexanol material into a dehydrogenation reaction unit through a feed inlet to perform cyclohexanol dehydrogenation reaction to obtain a crude alcohol ketone material, and discharging the crude alcohol ketone material through a crude alcohol ketone discharge outlet;

a ketone column recycle alcohol feed from the ketone column is recycled back to the dehydrogenation reaction unit.

12. The cyclohexanone refining process of claim 11 further comprising:

discharging a fusel-containing material enriched in intermediate accumulated impurities from a side line of a heavy impurity separation zone of the dividing wall column;

enabling the impurity-containing alcohol material enriched with the intermediate accumulated impurities from the partition tower to enter an alcohol tower for treatment to obtain an alcohol tower circulating alcohol material;

recycling alcohol column recycle alcohol material from the alcohol column back to the dehydrogenation reaction unit.

13. The cyclohexanone purification process according to claim 12, wherein the mass ratio of the purified alcohol ketone mixture to the impurity-containing alcohol material enriched in intermediate accumulated impurities is 3-10:1; and/or

The sum of the ketone column recycle alcohol material and the alcohol column recycle alcohol material is 0.01 to 0.99 mass percent of the cyclohexanol material fed to the dehydrogenation reaction unit.

14. The cyclohexanone refining process of claim 12 further comprising:

At least a portion of the fresh cyclohexanol feed is passed to the alcohol column for treatment.

15. A method for purifying cyclohexanone according to claim 12, wherein,

the operating pressure of the alcohol tower is 101-200kPa, the reflux ratio is 0.1-10, the tower top temperature is 80-190 ℃, and the tower bottom temperature is 180-250 ℃.

16. A method for purifying cyclohexanone according to claim 10, wherein,

the operation pressure of the partition tower is 1-90kPa, the reflux ratio is 10-800, the tower top temperature is 80-150 ℃, the tower bottom temperature is 130-180 ℃, and the total theoretical plates of the tower are 30-100;

wherein the theoretical plate number of the prefractionation area is 5-50, and the cross section area of the prefractionation area is 10-50% of the cross section area of the dividing wall column; the theoretical plate number of the alcohol ketone refining area is 15-70; the theoretical plate number of the light impurity separation zone is 5-30; the theoretical plate number of the heavy impurity separation zone is 5-30; the liquid phase distribution ratio of the light impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.005-0.99:1; the gas phase distribution ratio of the heavy impurity separation zone to the prefractionation zone and the alcohol ketone refining zone is 0.05-0.95:1;

the operation pressure of the ketone tower is 1-60kPa, the reflux ratio is 0.5-10, the tower top temperature is 35-100 ℃, and the tower bottom temperature is 50-150 ℃.

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