Device for refining acetophenone and alpha-phenethyl alcohol

Abstract

The utility model relates to a device for refining acetophenone and alpha-phenethyl alcohol, which comprises a first rectifying tower provided with a first inlet, a first outlet, a first discharge port and an extractant inlet; the second rectifying tower is provided with a second inlet, a second outlet and a second discharge port, and the second inlet is communicated with the first discharge port; the third rectifying tower is provided with a third reboiler which is provided with a third inlet, a third outlet and a third discharge port, the third outlet is formed in the top of the third rectifying tower, the third discharge port is formed in the bottom of the third rectifying tower, and the third reboiler of the third rectifying tower is communicated with the second outlet; the material flowing out of the second outlet is condensed by a third reboiler and then is branched into two paths, one path flows back to the upper part of the second rectifying tower, and the other path is communicated with a third inlet; the cooler is provided with a material inlet and a liquid outlet, the material inlet is communicated with the third outlet, and the liquid outlet is used for discharging alpha-phenethyl alcohol. The energy consumption is reduced.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, specifically to an apparatus for refining acetophenone and α-phenylethanol. Background Technology

[0002] Acetophenone and α-phenylethanol are important organic chemical raw materials, widely used in the fragrance, pharmaceutical, and chemical industries. The PO / SM process, which uses ethylbenzene, air, and propylene as raw materials to produce propylene oxide and styrene via co-oxidation, is a relatively mature international method. However, the reaction generates α-phenylethanol and the byproduct acetophenone. Acetophenone is concentrated at the top of a hydrogenation feed fractionation column after distillation, and then sent to a hydrogenation reactor for hydrogenation to produce α-phenylethanol. α-Phenylene is then dehydrated to produce the SM product. After concentration at the top of the hydrogenation feed fractionation column, the acetophenone content is approximately 70%, the α-phenylethanol content is approximately 25%, and other impurities account for approximately 5%. However, these two main compounds have very similar physicochemical properties, especially their boiling points of 202℃ and 203.5℃, respectively. This makes it difficult to achieve efficient separation using conventional distillation processes, resulting in high energy consumption and difficulty in achieving the high purity requirement of over 99.5%.

[0003] To address this issue, researchers have proposed various improved separation methods in recent years. For example, extractive distillation technology improves the separation effect by selecting a suitable extractant (such as glycerol) based on the different solubilities and relative volatility of acetophenone and 1-phenylethanol in glycerol. This is exemplified by the Chinese utility model patent application CN2010713615.3 (publication number CN105418397A), which discloses a method for separating acetophenone and 1-phenylethanol.

[0004] However, both distillation and extraction columns operate at high temperatures and require a large amount of heat source. This patent does not make full use of the heat source, resulting in high energy consumption. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a device for refining acetophenone and α-phenylethanol with low energy consumption, based on the current state of the technology.

[0006] The technical solution adopted by this utility model to solve the above-mentioned technical problems is: an apparatus for refining acetophenone and α-phenylethanol, comprising...

[0007] The first distillation column has a first inlet, a first outlet, a first discharge port and an extractant inlet. The first outlet is located at the top of the first distillation column and the first discharge port is located at the bottom of the first distillation column.

[0008] The second distillation column has a second inlet, a second outlet and a second discharge port, wherein the second inlet and the first discharge port are connected, the second outlet is located at the top of the second distillation column and the second discharge port is located at the bottom of the second distillation column;

[0009] The third distillation column is equipped with a third reboiler, which has a third inlet, a third outlet, and a third discharge port. The third outlet is located at the top of the third distillation column, and the third discharge port is located at the bottom of the third distillation column. The third reboiler of the third distillation column is connected to the second outlet. The material flowing out of the second outlet is condensed by the third reboiler and then branched into two paths. One path flows back to the upper part of the second distillation column, and the other path is connected to the third inlet.

[0010] The cooler has a material inlet and a drain outlet, the material inlet being connected to a third outlet, the drain outlet being used to discharge α-phenylethanol.

[0011] To further improve the separation efficiency of acetophenone and α-phenylethanol, the apparatus further includes a fourth distillation column for separating the heavy and light components in the mixture of acetophenone and α-phenylethanol. The fourth distillation column has a fourth inlet, a fourth outlet, a fourth discharge port, and a fourth material outlet. The fourth inlet is for feeding raw materials containing acetophenone and α-phenylethanol, the fourth outlet is for the light components to flow out, the fourth discharge port is for the heavy components to flow out, and the fourth material outlet is connected to the first inlet. The first distillation column first removes heavy components, light components, and other impurities from the raw material, so that the subsequent material mainly contains acetophenone and α-phenylethanol, thus improving both the separation efficiency and the separation purity.

[0012] Preferably, the fourth distillation column is a partitioned column, with the fourth inlet located on the feed side and the fourth material outlet located on the discharge side. Partitioned columns have a small footprint and offer good distillation efficiency.

[0013] To save energy, the adjacent column is equipped with a fourth reboiler. The first outlet is connected to the fourth reboiler of the adjacent column. The material flowing out of the first outlet is condensed in the fourth reboiler and then branches into two paths: one path supplies acetophenone for discharge, and the other path is connected to the upper part of the first distillation column. The vapor phase of the first distillation column serves as the heat source for the fourth reboiler, eliminating the need for an additional heat source for the fourth reboiler, thus saving energy and being environmentally friendly.

[0014] In the above scheme, a fourth condenser and a fourth buffer tank are sequentially provided downstream of the fourth outlet. The discharge port of the fourth buffer tank is connected to a fourth discharge pipe, which branches into two fourth branches. One of the fourth branches is connected to the upper part of the first distillation column, and the other fourth branch is used for the discharge of light components.

[0015] Preferably, the second discharge port of the second distillation column is connected to the extractant inlet of the first distillation column, and a cooling element for cooling the material is provided along the flow path between the second discharge port and the extractant inlet. This allows for the recycling and reuse of the extractant, saving costs.

[0016] Preferably, a first preheating element, a third preheating element, and a fourth preheating element are respectively provided upstream of the first inlet, the third inlet, and the fourth inlet to preheat the material, so as to improve the distillation effect of the material in the corresponding distillation column.

[0017] Preferably, the device includes a first heat exchanger, a third heat exchanger, and a fourth heat exchanger, all of which are located on the flow path between the second discharge port and the extractant inlet, and are spaced apart along the flow path.

[0018] The cooling components are three in number: a first cooling component, a third cooling component, and a fourth cooling component. The tube side of the first heat exchanger is connected to the first inlet, and the shell side of the first heat exchanger is connected to the extractant inlet and the second discharge port. The shell side serves as the first cooling component, and the tube side serves as the first heating component. Alternatively, the shell side of the first heat exchanger is connected to the first inlet, and the tube side of the first heat exchanger is connected to the extractant inlet and the second discharge port. The tube side serves as the first cooling component, and the shell side serves as the first heating component.

[0019] If the tube side of the third heat exchanger is connected to the third inlet, then the shell side of the third heat exchanger is connected to the extractant inlet and the second discharge port. The shell side serves as the third cooling element, and the tube side serves as the third heating element. Alternatively, if the shell side of the third heat exchanger is connected to the third inlet, then the tube side of the third heat exchanger is connected to the extractant inlet and the second discharge port. The tube side serves as the third cooling element, and the shell side serves as the third heating element.

[0020] If the tube side of the fourth heat exchanger is connected to the fourth inlet, then the shell side of the fourth heat exchanger is connected to the extractant inlet and the second discharge port. The shell side serves as the fourth cooling element, and the tube side serves as the fourth heating element. Alternatively, if the shell side of the fourth heat exchanger is connected to the fourth inlet, then the tube side of the fourth heat exchanger is connected to the extractant inlet and the second discharge port. The tube side serves as the fourth cooling element, and the shell side serves as the fourth heating element.

[0021] In this way, as the extractant flows back from the second discharge port of the second distillation column to the extractant inlet of the first distillation column, it also acts as a heat source to heat the materials entering the first, third, and fourth inlets. This eliminates the need to set up additional heat sources upstream of the first, third, and fourth inlets. Furthermore, the extractant cools itself while heating the materials, achieving two benefits at once.

[0022] In the above scheme, a third condenser and a third buffer tank are sequentially provided downstream of the third reboiler. Both the third reboiler and the third condenser are connected to the third buffer tank. The discharge port of the third buffer tank is connected to a third discharge pipe, which branches into two third branches. One of the third branches is connected to the third inlet, and the other third branch is connected to the upper part of the second distillation column to maintain the balance of temperature, pressure, etc. in the third distillation column.

[0023] Because the condensate contains a large amount of α-phenylethanol after the material is condensed by the cooler, but the non-condensable gas also contains a small amount of α-phenylethanol, the device also includes a buffer container in order to further recover α-phenylethanol. A fifth condenser is provided downstream of the material discharge port of the cooler, and the fifth condenser and the discharge port are connected to the buffer container.

[0024] Preferably, the cooler is a heat exchanger, in which material flows through the tube side (or shell side) of the heat exchanger for further condensation. During the material flow, the material in the shell side (or tube side), such as water, is heated. The heated water can be used for other purposes, which is energy-saving and environmentally friendly.

[0025] Compared with the prior art, the advantages of this utility model are as follows: By connecting the third reboiler of the third distillation column to the second outlet, the third distillation column and the second distillation column are thermally coupled. In this way, the gas phase flowing out of the second outlet of the second distillation column becomes the heat source of the reboiler of the third distillation column, eliminating the need for an additional heat source to heat the third reboiler. At the same time, the third reboiler also acts as a cold source to cool the material flowing out of the second outlet. This fully utilizes the heat generated during the production process of the device, saving energy and protecting the environment. It has significant practicality and economic benefits and broad application prospects. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of an embodiment of the present utility model (only the tube side of the first heat exchanger, the third heat exchanger, and the fourth heat exchanger is shown);

[0027] Figure 2 This is a process flow diagram of an embodiment of the present invention (only the shell side of the first heat exchanger, the third heat exchanger, and the fourth heat exchanger are shown). Detailed Implementation

[0028] Various exemplary embodiments of the present invention are now described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, features and implementations of the present invention.

[0029] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, regarding numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0030] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0031] Various improvements and variations can be made to the specific embodiments described in this utility model without departing from the scope or spirit of this utility model, which will be obvious to those skilled in the art. Other embodiments derived from this utility model description will also be obvious to those skilled in the art. This utility model description and embodiments are merely exemplary.

[0032] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0033] like Figure 1 , 2 As shown, the apparatus for refining acetophenone and α-phenylethanol in this preferred embodiment includes a first distillation column 1, a second distillation column 2, a third distillation column 3, a fourth distillation column 4, and a cooler 5.

[0034] The fourth distillation column 4 is used to separate the heavy components and light components in the raw material containing acetophenone and α-phenylethanol. The first distillation column 1 first removes the heavy components, light components and other impurities from the raw material, so that the subsequent material basically contains only acetophenone and α-phenylethanol, which not only improves the separation effect, but also improves the separation purity.

[0035] The fourth distillation column 4 has a fourth inlet 41, a fourth outlet 42, a fourth discharge port 43 and a fourth material outlet 44. The fourth inlet 41 is used to feed raw materials containing acetophenone and α-phenylethanol, the fourth outlet 42 is used to feed light components, and the fourth discharge port 43 is used to feed heavy components.

[0036] In this application, the fourth distillation column 4 is a partition wall column equipped with a fourth reboiler 48. The partition wall column has a small footprint and good distillation effect. The fourth inlet 41 is located on the feed side of the partition wall column, the fourth material outlet 44 is located on the discharge side of the partition wall column, the fourth outlet 42 is located at the top of the fourth distillation column 4, and the fourth discharge port 43 is located at the bottom of the fourth distillation column 4.

[0037] Downstream of the fourth outlet 42, a fourth condenser 45 and a fourth buffer tank 46 are sequentially provided. The gas phase flowing out of the fourth outlet 42 is condensed into liquid by the fourth condenser 45 and then enters the fourth buffer tank 46. The discharge port of the fourth buffer tank 46 is connected to a fourth discharge pipe 47. The fourth discharge pipe 47 branches into two fourth branch pipes 471. One of the fourth branch pipes 471 is connected to the upper part of the fourth distillation column 4, and the other fourth branch pipe 471 is used for the discharge of light components. A fourth cooler 472 is provided on the fourth branch pipe 471 so that the light components are cooled before flowing out of the device.

[0038] The fourth discharge port 43 is for discharging heavy components. A cooling device 431 is installed downstream of the fourth discharge port 43. The heavy components are cooled by the cooling device 431 before being discharged from the device. The liquid phase in the upper part of the fourth distillation column 4 is self-circulated by a pump.

[0039] The fourth material outlet 44 is connected to the first inlet 11 of the first distillation column 1 to further distill the material after removing light and heavy components in the first distillation column 1. The first distillation column 1 has a first inlet 11, a first outlet 12, a first discharge port 13, and an extractant inlet 14. The first outlet 12 is located at the top of the first distillation column 1, the first discharge port 13 is located at the bottom of the first distillation column 1, and the first inlet 11 and the extractant inlet 14 are both located on the side of the first distillation column 1.

[0040] The first outlet 12 of the first distillation column 1 is connected to the fourth reboiler 48 of the adjacent column. The material flowing out of the first outlet 12 is condensed by the fourth reboiler 48 and then branches into two paths: one path is for acetophenone discharge, and the other path is connected to the upper part of the first distillation column 1.

[0041] Specifically, in this application, in order to further recover acetophenone, a fourth buffer 40 and a fourth condenser 49 are sequentially provided downstream of the fourth reboiler 48. The condensate after being condensed by the fourth reboiler 48 flows into the fourth buffer 40. The non-condensable gas that is not condensed by the fourth reboiler 48 is condensed by the fourth condenser 49, and the condensate also enters the fourth buffer 40 under its own gravity. The discharge port of the fourth buffer 40 is connected to a fourth discharge pipe, which branches into two fourth discharge branches 401. One of the fourth discharge branches 401 is connected to the upper part of the first distillation column 1, and the other fourth discharge branch 401 is used to discharge acetophenone. The fourth discharge branch 401 is equipped with a fourth cooling device 403 so that the acetophenone is cooled before being discharged.

[0042] As can be seen from the above, the gas phase of the first distillation column 1 serves as the heat source (thermally coupled) for the fourth reboiler 48, heating the fourth reboiler 48 without the need for an additional heat source. The fourth reboiler 48 also serves as a cold source for cooling the material flowing out from the first outlet 12, achieving two goals at once, saving energy and protecting the environment.

[0043] The material after distillation in the first distillation column 1 enters the second distillation column 2 for further distillation. The second distillation column 2 has a second inlet 21, a second outlet 22, and a second discharge port 23. The second inlet 21 is connected to the first discharge port 13. The second inlet 21 is located on the side of the second distillation column 2, the second outlet 22 is located at the top of the second distillation column 2, and the second discharge port 23 is located at the bottom of the second distillation column 2.

[0044] The material after distillation in the second distillation column 2 enters the third distillation column 3 for further distillation. The third distillation column 3 has a third inlet 31, a third outlet, and a third discharge port 33. The third outlet is located at the top of the third distillation column 3, and the third discharge port 33 is located at the bottom of the third distillation column 3. In this application, there are three third inlets 31, all located on the side of the third distillation column 3, which ensures uniform material entry and improves the separation effect. Of course, the number of third inlets 31 is not limited to three and can also be other numbers.

[0045] The third distillation column 3 is equipped with a third reboiler 37, which is connected to the second outlet 22 of the second distillation column 2. The material flowing out of the second outlet 22 is condensed by the third reboiler 37 and then branched into two streams. One stream flows back to the upper part of the third distillation column 3, and the other stream is connected to the third inlet 31.

[0046] Specifically in this application, because the third reboiler 37 may not be able to fully condense the material flowing out from the second outlet 22, in order to further recover the material, a third buffer tank 35 and a third condenser 34 are sequentially provided downstream of the third reboiler 37. The condensate after being condensed by the third reboiler 37 flows into the third buffer tank 35, and the non-condensable gas that is not condensed by the third reboiler 37 is condensed by the third condenser 34, and the condensate also enters the third buffer tank 35 under its own gravity.

[0047] The discharge port of the third buffer tank 35 is connected to a third discharge pipe 36, which branches into two third branch pipes 361. One of the third branch pipes 361 is connected to the third inlet 31, and the other third branch pipe 361 is connected to the upper part of the second distillation column 2 to maintain the balance of temperature, pressure and other parameters in the second distillation column 2.

[0048] The third reboiler 37 of the third distillation column 3 is connected to the second outlet 22 of the second distillation column 2, so that the third distillation column 3 and the second distillation column 2 are thermally coupled. In this way, the gas phase flowing out of the second outlet 22 of the second distillation column 2 is the heat source of the third reboiler 37 of the third distillation column 3. There is no need to set up an additional heat source to heat the third reboiler 37, making full use of the heat source generated by the production operation of the unit itself. At the same time, the third reboiler 37 also serves as a cold source for the gas phase flowing out of the second outlet 22, achieving two goals at once, saving energy and protecting the environment.

[0049] The material discharged from the third discharge port 33 is also cooled by the cooling device 431 before being discharged from the device.

[0050] The cooler 5 has a material inlet, a material outlet 52 and a liquid outlet 53. The material inlet is connected to the third outlet of the third distillation column 3, and the liquid outlet 53 is used to discharge α-phenylethanol.

[0051] Because the condensate contains a large amount of α-phenylethanol after the material is condensed by the cooler 5, but the non-condensable gas also contains a small amount of α-phenylethanol, in order to further recover α-phenylethanol, the device also includes a buffer container 54. A fifth condenser 55 is provided downstream of the material discharge port 52 of the cooler 5. The fifth condenser 55 and the discharge port 53 are both connected to the buffer container 54. After the non-condensable gas is condensed by the fifth condenser 55, the condensate also enters the buffer container 54.

[0052] In this application, the cooler 5 is a heat exchanger. In this way, the gas phase supplied from the third distillation column 3 flows through the tube side (or shell side) of the heat exchanger for condensation. During the gas phase flow, the material in the shell side (or tube side), such as water, will be heated. The heated material can then be used for other purposes, which is energy-saving and environmentally friendly.

[0053] Furthermore, the second discharge port 23 of the second distillation column 2 is connected to the extractant inlet 14 of the first distillation column 1, thus enabling the recycling and reuse of the extractant and saving costs. Additionally, a feed inlet (not shown in the figure) for the extractant is provided along the flow path between the second discharge port 23 and the extractant inlet 14. When the device is first turned on, the extractant is introduced into the first distillation column 1 through this inlet. After the device is turned on again, this feed inlet can be closed because the extractant can be recycled, eliminating the need to introduce new extractant.

[0054] Cooling elements for cooling the material are provided on the flow path between the second discharge port 23 and the extractant inlet 14. There are three cooling elements: the first cooling element, the third cooling element, and the fourth cooling element.

[0055] In addition, a first preheating element, a third preheating element, and a fourth preheating element are respectively provided upstream of the first inlet 11, the third inlet 31, and the fourth inlet 41 to preheat the material, so as to improve the distillation effect of the material in the corresponding distillation column.

[0056] The device of this application includes a first heat exchanger 61, a third heat exchanger 62, and a fourth heat exchanger 63. The first heat exchanger 61, the third heat exchanger 62, and the fourth heat exchanger 63 are all located on the flow path between the second discharge port 23 and the extractant inlet 14, and are arranged at intervals along the flow path.

[0057] If the tube side of the first heat exchanger 61 is connected to the first inlet 11, then the shell side of the first heat exchanger 61 is connected to the extractant inlet 14 and the second discharge port 23. The shell side serves as the first cooling element, and the tube side serves as the first heating element. Alternatively, if the shell side of the first heat exchanger 61 is connected to the first inlet 11, then the tube side of the first heat exchanger 61 is connected to the extractant inlet 14 and the second discharge port 23. The tube side serves as the first cooling element, and the shell side serves as the first heating element.

[0058] If the tube side of the third heat exchanger 62 is connected to the third inlet 31, then the shell side of the third heat exchanger 62 is connected to the extractant inlet 14 and the second discharge port 23. The shell side serves as the third cooling element, and the tube side serves as the third heating element. Alternatively, if the shell side of the third heat exchanger 62 is connected to the third inlet 31, then the tube side of the third heat exchanger 62 is connected to the extractant inlet 14 and the second discharge port 23. The tube side serves as the third cooling element, and the shell side serves as the third heating element.

[0059] If the tube side of the fourth heat exchanger 63 is connected to the fourth inlet 41, then the shell side of the fourth heat exchanger 63 is connected to the extractant inlet 14 and the second discharge port 23. The shell side serves as the fourth cooling element, and the tube side serves as the fourth heating element. Alternatively, if the shell side of the fourth heat exchanger 63 is connected to the fourth inlet 41, then the tube side of the fourth heat exchanger 63 is connected to the extractant inlet 14 and the second discharge port 23. The tube side serves as the fourth cooling element, and the shell side serves as the fourth heating element.

[0060] In this embodiment, the material flowing out from the second discharge port 23 flows through the tube side of the first heat exchanger 61, the third heat exchanger 62, and the fourth heat exchanger 63, and the material entering the first inlet 11, the third inlet 31, and the fourth inlet 41 flows through the shell side of the corresponding heat exchanger in sequence.

[0061] In this way, during the reflux of the extractant from the second discharge port 23 of the second distillation column 2 to the extractant inlet 14 of the first distillation column 1, the extractant also acts as a heat source to heat the materials entering the first inlet 11, the third inlet 31, and the fourth inlet 41. This eliminates the need to set up additional heat sources upstream of the first inlet 11, the third inlet 31, and the fourth inlet 41. Furthermore, the extractant cools itself down while heating the materials, achieving two benefits at once.

[0062] As can be seen from the above, the material undergoes three stages of heat exchange during its flow from the second discharge port 23 to the extractant inlet 14: the first stage heat exchange reaches 198–203°C, the second stage heat exchange reaches 192–198°C, and the third stage heat exchange reaches 152–160°C.

[0063] In addition, both the third distillation column 3 and the fourth distillation column 4 are equipped with vacuum systems connected to them at the top to maintain the pressure inside the columns. The reboilers of the first distillation column 1 and the second distillation column 2 both require forced circulation heating with high-pressure steam. These are existing technologies and will not be described in detail here.

[0064] The process method for refining acetophenone and α-phenylethanol according to this application uses the above-mentioned apparatus, and the process method includes the following steps:

[0065] (1) The raw material containing acetophenone and α-phenylethanol is fed into the partition column through the fourth inlet 41 for distillation. The light components in the raw material flow out through the fourth outlet 42, and the heavy components in the raw material flow out through the fourth discharge port 43. The raw material after removing the light and heavy components flows out through the fourth material outlet 44 to the first inlet 11 for distillation in the first distillation column 1. The extractant is introduced into the extractant inlet 14 of the first distillation column 1.

[0066] (2) The material flowing out from the first outlet 12 is condensed by the fourth reboiler 48 of the adjacent tower and then enters the fourth buffer 40. The non-condensable gas is condensed by the fourth condenser 49 and the condensate also enters the fourth buffer 40. Then the material flowing out from the fourth buffer 40 branches into two paths. One path is acetophenone and is discharged, while the other path is returned to the upper part of the first distillation column 1.

[0067] The material flowing out from the first discharge port 13 flows through the second inlet 21 to the second distillation column 2 for distillation;

[0068] (3) The material flowing out from the second outlet 22 is condensed by the third reboiler 37 of the third distillation column 3 and then enters the third buffer tank 35. The non-condensable gas is condensed by the third condenser 34 and also enters the third buffer tank 35. The material flowing out from the third buffer tank 35 is branched into two paths. One path of material flows back to the upper part of the second distillation column 2, and the other path of material enters the third distillation column 3 through the third inlet 31.

[0069] The material flowing out of the second discharge port 23 is cooled by the cooling unit and then flows back to the first distillation column 1 through the extractant inlet 14. During the flow of the material flowing out of the second discharge port 23, it exchanges heat with the material entering the first inlet 11, the third inlet 31 and the fourth inlet 41, which not only cools itself down, but also heats the material entering the first inlet 11, the third inlet 31 and the fourth inlet 41.

[0070] (4) After the material flowing out of the third outlet of the third distillation column 3 is condensed by the cooler 5, part of it flows back to the top of the third distillation column 3, and the other part enters the third buffer tank 35. After the non-condensable gas is condensed by the third condenser 34, the condensate also enters the third buffer tank 35. The material in the third buffer tank 35 is α-phenylethanol.

[0071] The structures of the components in this application, such as distillation columns, reboilers, condensers, cooling components, and heat exchangers, all adopt existing structures. In addition, pumps for conveying materials can be installed on the pipeline as needed.

[0072] To test the effectiveness of the apparatus and process method of this application, the following tests were conducted:

[0073] The applicant conducted the following comparative experiment:

[0074] The feed rate of the raw materials containing acetophenone and α-phenylethanol is 1000 kg / h. The operating pressure of the fourth distillation column 4 is 20 kPaA, and the operating temperature is 128.6℃. The operating pressure of the first distillation column 1 is 50 kPaA, and the operating temperature is 177.1℃. The operating pressure of the second distillation column 2 is 25 kPaA, and the operating temperature is 155℃. The operating pressure of the third distillation column 3 is 15 kPaA, and the operating temperature is 156.6℃.

[0075] The comparative experiment was conducted under a lower vacuum, and no thermal coupling was performed between the fourth distillation column 4 and the first distillation column 1, or between the second distillation column 2 and the third distillation column 3. The final purity of the acetophenone product reached 98.5%, and the purity of the α-phenylethanol product reached 98.5%. The energy consumption was 45% higher than that of the thermal coupling process, the material polymerization loss was greater, and the production efficiency was lower.

[0076] Furthermore, the applicant used the apparatus and process methods described in this application to conduct the following tests, Experiment 1 and Experiment 2:

[0077] Experiment 1:

[0078] The feed rate of the raw materials containing acetophenone and α-phenylethanol is 3500 kg / h. The operating pressure of the fourth distillation column 4 is 4 kPaA, and the operating temperature is 84.7℃. The operating pressure of the first distillation column 1 is 28 kPaA, and the operating temperature is 155.8℃. The operating pressure of the second distillation column 2 is 16 kPaA, and the operating temperature is 142.6℃. The operating pressure of the third distillation column 3 is 3 kPaA, and the operating temperature is 104.5℃.

[0079] The tests showed that the purity of the final acetophenone product reached 99.6%, the purity of the α-phenylethanol product reached 99.7%, energy consumption was reduced by 20%, material loss was reduced by 15%, and production efficiency was increased by 30%.

[0080] Experiment 2:

[0081] The feed rate of the raw materials containing acetophenone and α-phenylethanol is 4000 kg / h. The operating pressure of the fourth distillation column 4 is 10 kPaA, and the operating temperature is 95℃. The operating pressure of the first distillation column 1 is 35 kPaA, and the operating temperature is 165℃. The operating pressure of the second distillation column 2 is 25 kPaA, and the operating temperature is 158℃. The operating pressure of the third distillation column 3 is 5 kPaA, and the operating temperature is 115℃.

[0082] The tests showed that the purity of the final acetophenone product reached 99.55%, the purity of the α-phenylethanol product reached 99.6%, energy consumption was reduced by 25%, material loss was reduced by 20%, and production efficiency was increased by 35%.

[0083] By using the apparatus and process described in this application, the purity of the acetophenone product and α-phenylethanol separated in this application both reach over 99.5% (wt), and the recovery efficiency is high, reducing material loss.

[0084] In summary, this application overcomes the technical defects of existing separation and purification of acetophenone and α-phenylethanol products, not only achieving the preparation of high-purity products, but also greatly reducing the consumption of cooling water and system heat energy, and saving equipment investment costs. It has significant technological advancements and economic benefits, and has broad application prospects.

Claims

1. An apparatus for purifying acetophenone and α-phenylethanol, comprising: The first distillation column (1) has a first inlet (11), a first outlet (12), a first discharge port (13) and an extractant inlet (14). The first outlet (12) is located at the top of the first distillation column (1) and the first discharge port (13) is located at the bottom of the first distillation column (1). The second distillation column (2) has a second inlet (21), a second outlet (22) and a second discharge port (23), wherein the second inlet (21) is connected to the first discharge port (13), the second outlet (22) is located at the top of the second distillation column (2), and the second discharge port (23) is located at the bottom of the second distillation column (2); Its features are, Also includes The third distillation column (3) is equipped with a third reboiler (37). The third distillation column (3) has a third inlet (31), a third outlet, and a third discharge port (33). The third outlet is located at the top of the third distillation column (3), and the third discharge port (33) is located at the bottom of the third distillation column (3). The third reboiler (37) of the third distillation column (3) is connected to the second outlet (22). The material flowing out from the second outlet (22) is condensed by the third reboiler (37) and then branched into two paths. One path is connected to the upper part of the second distillation column (2), and the other path is connected to the third inlet (31). The cooler (5) has a material inlet and a drain outlet (53), the material inlet and the third outlet are connected, and the drain outlet (53) is used to supply α-phenylethanol.

2. The apparatus according to claim 1, characterized in that: It also includes a fourth distillation column (4) for separating the heavy and light components in a mixture of acetophenone and α-phenylethanol. The fourth distillation column (4) has a fourth inlet (41), a fourth outlet (42), a fourth discharge port (43), and a fourth material outlet (44). The fourth inlet (41) is for feeding raw materials containing acetophenone and α-phenylethanol, the fourth outlet (42) is for the light components to flow out, the fourth discharge port (43) is for the heavy components to flow out, and the fourth material outlet (44) is connected to the first inlet (11).

3. The apparatus according to claim 2, characterized in that: The fourth distillation column (4) is a partition column, the fourth inlet (41) is located on the feed side of the partition column, and the fourth material outlet (44) is located on the discharge side of the partition column.

4. The apparatus according to claim 3, characterized in that: The partition column is equipped with a fourth reboiler (48). The first outlet (12) is connected to the fourth reboiler (48) of the partition column. The material flowing out from the first outlet (12) is condensed by the fourth reboiler (48) and then branches into two paths. One path is for acetophenone to be discharged, and the other path is connected to the upper part of the first distillation column (1).

5. The apparatus according to claim 2, characterized in that: The second discharge port (23) of the second distillation column (2) is connected to the extractant inlet (14) of the first distillation column (1), and a cooling element for cooling the material is provided on the flow path between the second discharge port (23) and the extractant inlet (14).

6. The apparatus according to claim 5, characterized in that: A first preheating element, a third preheating element, and a fourth preheating element for preheating materials are respectively provided upstream of the first inlet (11), the third inlet (31), and the fourth inlet (41).

7. The apparatus according to claim 6, characterized in that: The device includes a first heat exchanger (61), a third heat exchanger (62), and a fourth heat exchanger (63). The first heat exchanger (61), the third heat exchanger (62), and the fourth heat exchanger (63) are all located on the flow path of the second discharge port (23) and the extractant inlet (14), and are spaced apart along the flow path. The cooling components are three in number: a first cooling component, a third cooling component, and a fourth cooling component. The tube side of the first heat exchanger (61) is connected to the first inlet (11), and the shell side of the first heat exchanger (61) is connected to the extractant inlet (14) and the second discharge port (23). The shell side serves as the first cooling component, and the tube side serves as the first heating component. Alternatively, the shell side of the first heat exchanger (61) is connected to the first inlet (11), and the tube side of the first heat exchanger (61) is connected to the extractant inlet (14) and the second discharge port (23). The tube side serves as the first cooling component, and the shell side serves as the first heating component. The tube side of the third heat exchanger (62) is connected to the third inlet (31), and the shell side of the third heat exchanger (62) is connected to the extractant inlet (14) and the second discharge port (23). The shell side serves as the third cooling element, and the tube side serves as the third heating element. Alternatively, the shell side of the third heat exchanger (62) is connected to the third inlet (31), and the tube side of the third heat exchanger (62) is connected to the extractant inlet (14) and the second discharge port (23). The tube side serves as the third cooling element, and the shell side serves as the third heating element. The tube side of the fourth heat exchanger (63) is connected to the fourth inlet (41), and the shell side of the fourth heat exchanger (63) is connected to the extractant inlet (14) and the second discharge port (23). The shell side serves as the fourth cooling element, and the tube side serves as the fourth heating element. Alternatively, the shell side of the fourth heat exchanger (63) is connected to the fourth inlet (41), and the tube side of the fourth heat exchanger (63) is connected to the extractant inlet (14) and the second discharge port (23). The tube side serves as the fourth cooling element, and the shell side serves as the fourth heating element.

8. The apparatus according to any one of claims 1 to 7, characterized in that: The cooler (5) is a heat exchanger.

9. The apparatus according to any one of claims 1 to 7, characterized in that: Downstream of the third reboiler (37) are a third buffer tank (35) and a third condenser (34). Both the third reboiler (37) and the third condenser (34) are connected to the third buffer tank (35). The discharge port of the third buffer tank (35) is connected to a third discharge pipe (36). The third discharge pipe (36) branches into two third branches (361). One of the third branches (361) is connected to the third inlet (31), and the other third branch (361) is connected to the upper part of the second distillation column (2).

10. The apparatus according to any one of claims 1 to 7, characterized in that: It also includes a buffer container (54), and a fifth condenser (55) is provided downstream of the material discharge port (52) of the cooler (5). The fifth condenser (55) and the drain port (53) are both connected to the buffer container (54).

Images