Device for preparing cyclohexanol through cyclohexyl acetate hydrogenation

Abstract

The invention provides a device for preparing cyclohexanol by cyclohexyl acetate hydrogenation, which comprises: a reactor, the reactor comprises a feed inlet, a gas-liquid discharge outlet and a porous membrane, the porous membrane is loaded with a catalytic active component; the hydrogen feeding pipe is connected with a feeding hole of the reactor; and the cyclohexyl acetate feeding pipe is connected with the feeding hole of the reactor. The invention also provides a method for producing cyclohexanol by using the device provided by the invention.

Description

Technical Field

[0001] The invention belongs to the technical field of fine chemical organic synthesis, and specifically relates to a device and a method for producing cyclohexanol, and more specifically, to a device and a method for producing cyclohexanol by catalytic hydrogenation of cyclohexyl acetate. Background Art

[0002] Cyclohexanol is an excellent medium-to-high boiling point organic chemical product and an important intermediate in the production of nylon. Cyclohexanol can be oxidized to produce adipic acid, and cyclohexanol can also be dehydrogenated to produce cyclohexanone. Cyclohexanone and adipic acid are the main raw materials for the production of polyamide plastics nylon 6 and nylon 66, respectively. Ethanol is also an important chemical raw material and an important blending component of gasoline.

[0003] Traditional methods for preparing cyclohexanol mainly include cyclohexane oxidation and phenol hydrogenation. Currently, cyclohexane oxidation is mostly used in industry.

[0004] Asahi Kasei Corporation of Japan has developed a new process for producing cyclohexene by partial hydrogenation of benzene and then hydrating cyclohexene to produce cyclohexanol. All reactants in this process are converted into products, which saves energy and reduces emissions, and the reaction process is safe. However, cyclohexene is not miscible with water, and 1,4-dioxane or the like needs to be added as a cosolvent to increase the solubility of cyclohexene in water. This process has the disadvantages of low cyclohexene conversion rate, high reaction temperature, and difficulty in separating the product cyclohexanol from the cosolvent after the reaction.

[0005] In recent years, for the preparation of cyclohexanol, there is also a method of esterifying cyclohexene with acetic acid to generate cyclohexyl acetate, and then hydrogenating cyclohexyl acetate to generate cyclohexanol. This method has high atomic utilization, can significantly reduce the production cost and energy consumption of cyclohexanol, and has obvious economic and technical advantages. However, the hydrogenation process belongs to a multiphase reaction, and the gas-liquid phase mass transfer area of ​​the existing reactor is limited. During the reaction, cyclohexyl acetate and hydrogen cannot be fully mixed, and the mass transfer efficiency between the gas-liquid phase is low, and the reaction efficiency is low. On the other hand, the temperature and pressure of the esterification reaction are high, which causes the safety and stability of the system to be greatly reduced. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a device and method for producing cyclohexanol by hydrogenating cyclohexyl acetate, innovatively introducing a porous membrane loaded with catalytic active components to strengthen gas-liquid mass transfer and synchronize catalytic reaction, thereby improving the conversion rate of cyclohexyl acetate and reducing the reaction temperature and pressure, and ultimately achieving efficient synthesis of cyclohexanol.

[0007] One aspect of the present application provides a device for producing cyclohexanol by hydrogenating cyclohexyl acetate, comprising: a reactor, the reactor comprising a feed port, a gas-liquid discharge port, and a porous membrane, wherein the porous membrane is loaded with catalytically active components; a hydrogen feed pipe connected to the feed port of the reactor; and a cyclohexyl acetate feed pipe connected to the feed port of the reactor. The device may also include a gas-liquid separator connected to the gas-liquid discharge port of the reactor.

[0008] Another aspect provides a method for producing cyclohexanol using the device of the present invention, the method comprising: feeding hydrogen and cyclohexyl acetate into a reactor equipped with a porous membrane, allowing the hydrogen and cyclohexyl acetate to pass through the porous membrane for a hydrogenation reaction, wherein the porous membrane carries a catalytically active component. The method may further comprise: introducing the gas-liquid mixture after the reaction into a gas-liquid separation tank for gas-liquid separation.

[0009] In another aspect, the present application provides use of the porous membrane loaded with catalytically active components described in the present invention in manufacturing the device described in the present invention.

[0010] In another aspect, the present application provides use of the porous membrane loaded with catalytically active components described in the present invention in implementing the method described in the present invention.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] (1) Hydrogen is well dispersed and has high utilization rate. The present invention uses a porous membrane to enhance mass transfer, significantly improving the gas-liquid mass transfer efficiency;

[0013] (2) The reaction temperature and pressure are significantly reduced. This device significantly improves the reaction efficiency and reduces the temperature and pressure required for the reaction by strengthening gas-liquid mass transfer;

[0014] (3) It is preferred to adopt a gas-liquid co-current upward flow method to achieve efficient contact between the gas and liquid phases, thereby improving the conversion rate and product selectivity.

[0015] (4) The device of the present invention can be operated continuously, with material being fed and discharged simultaneously, thus significantly improving the reaction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of a device according to one embodiment of the present invention; the description of the reference numerals is as follows:

[0017] 1. Reactor body; 2. Plate and frame porous membrane assembly; 3. Hydrogen feed pipe; 4. Cyclohexyl acetate feed pipe; 5. Hydrogenation liquid pipeline; 6. Gas-liquid separation tank; 7. Hydrogen circulation pipeline. DETAILED DESCRIPTION

[0018] "Scope" disclosed herein is defined in the form of lower limit and upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular range. The scope defined in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a particular parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0019] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0020] In this application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0021] In the present application, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0022] In this application, unless otherwise specified, the terms "include" and "comprising" mentioned herein may be open-ended or closed-ended. For example, the terms "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0023] In the description of this article, it should be noted that, unless otherwise specified, "above" and "below" are inclusive of the number itself, and "several" in "one or several" means two or more.

[0024] In the description herein, unless otherwise specified, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0025] Herein, unless otherwise specified, percentage (%) or part refers to percentage by weight or part by weight relative to the composition.

[0026] Herein, if there is no contrary description, the sum of the contents of the various components in the composition is 100%.

[0027] Herein, if there is no contrary description, the sum of the parts of each component in the composition may be 100 parts by weight.

[0028] In this document, unless otherwise specified, "a combination thereof" means a multi-component mixture of the elements described, for example a mixture of two, three, four and up to the maximum possible multi-component mixture.

[0029] If not specifically stated, the terms "a" or "an" used in the present specification means "at least one".

[0030] Herein, unless otherwise stated, all reactions are carried out at normal temperature and pressure.

[0031] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0032] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0034] One aspect of the present application provides a device for producing cyclohexanol by hydrogenating cyclohexyl acetate, comprising:

[0035] A reactor, the reactor comprising a feed inlet, a gas-liquid discharge port and a porous membrane, wherein the porous membrane is loaded with catalytically active components;

[0036] a hydrogen feed pipe connected to the feed port of the reactor; and

[0037] A cyclohexyl acetate feed pipe connected to the feed port of the reactor.

[0038] Reactor

[0039] Preferably, the reactor is a gas-liquid co-current upward reactor. As used herein, "gas-liquid co-current upward reactor" means that the raw liquid and gas enter the reactor cavity from the feed port, pass through the porous membrane loaded with catalytic active components from bottom to top to react, and then are extracted from the gas-liquid discharge port. From the perspective of relative position, the relative position relationship between the feed port, the gas-liquid discharge port and the porous membrane is that in the vertical direction of the reactor, the feed port is at a lower position, the porous membrane is at a middle position, and the gas-liquid discharge port is at a higher position.

[0040] In some embodiments, the feed port is arranged at the bottom of the reactor, the porous membrane is arranged at the middle section of the reactor, and the gas-liquid discharge port is arranged at the top of the reactor. More specifically, "the feed port is arranged at the bottom of the reactor", wherein "the bottom of the reactor" refers to the area within 30% of the overall height of the reactor vertically from the lowest point of the reactor; "the porous membrane is arranged at the middle section of the reactor", wherein "the middle section of the reactor" refers to the area within 20% of the overall height of the reactor vertically from the center point of the reactor, that is, the area occupying 40% of the middle of the reactor in the vertical direction of the reactor; "the gas-liquid discharge port is arranged at the top of the reactor", wherein "the top of the reactor" refers to the area within 30% of the overall height of the reactor vertically from the highest point of the reactor.

[0041] Porous membrane loaded with catalytically active components

[0042] In some embodiments, the porous membrane is a plate-and-frame flat membrane. The flat membrane is loaded onto the plate-and-frame assembly by a threaded press, and the plate-and-frame membrane assembly is connected to each other by a flange and connected to the reactor body. Preferably, the porous membrane is installed in the reactor in a direction parallel to the cross section of the reactor, for example, the inclination angle of the porous membrane to the cross section of the reactor does not exceed 10°. Preferably, the porous membrane covers most of the cross-sectional area of ​​the reactor in the plane, for example, 80%, 90% or 100% of the cross-sectional area of ​​the reactor.

[0043] Preferably, the pore size of the porous membrane is 50 nm to 2000 nm, or 100 to 1500 nm, or 200 to 1200 nm.

[0044] The number of the porous membranes used in the present application can be one or more, for example, 1, 2, 3, 4, 5, 6, 7 or more. For example, a plurality of porous membranes are installed in the reactor in a parallel and spaced manner.

[0045] Preferably, the thickness of the porous membrane is 0.1-10 mm, or 1-6 mm, or 3-5 mm.

[0046] Preferably, the material of the porous membrane comprises one or any combination of silicon oxide, aluminum oxide and zirconium oxide. Preferably, the catalytically active component comprises one or any combination of Cu, Zn and Fe. Preferably, the loading amount of the active component is 0.1 wt%-10 wt% based on the weight of the porous membrane. Preferably, the active component is loaded onto the porous membrane by atomic vapor deposition, specifically, the active component is plated on the surface of the porous membrane layer by layer in the form of a single atomic film.

[0047] Other devices

[0048] In some embodiments, the device according to the present application may further include a gas-liquid separator connected to the gas-liquid outlet of the reactor. The gas-liquid separator separates the gas-liquid mixture after the reaction. For example, the temperature of the gas-liquid separator is 10°C to 20°C.

[0049] In some embodiments, the device may further include a hydrogen circulation pipeline. Preferably, the hydrogen separated from the gas and liquid is circulated into the reactor through the hydrogen circulation pipeline to participate in the reaction.

[0050] In some embodiments, the device may further include a hydrogen source connected to the hydrogen feed pipe, and a cyclohexyl acetate storage tank connected to the cyclohexyl acetate feed pipe.

[0051] In some embodiments, the device may further include a hydrogenation product tank, and the liquid phase separated from the gas-liquid separator enters the hydrogenation product tank to obtain a mixed product.

[0052] Another aspect of the present application provides a method for producing cyclohexanol using the device of the present application, wherein the method comprises: feeding hydrogen and cyclohexyl acetate into a reactor equipped with a porous membrane, allowing the hydrogen and cyclohexyl acetate to pass through the porous membrane for a hydrogenation reaction, wherein the porous membrane is loaded with a catalytically active component.

[0053] Preferably, the gas-liquid mixture of hydrogen and cyclohexyl acetate enters the reactor from the bottom of the reactor and flows upward. The hydrogen is rapidly broken down by the porous membrane and reacts rapidly with the cyclohexyl acetate under the catalytic action of the catalytically active components supported on the porous membrane.

[0054] In some embodiments, the method further comprises: introducing the gas-liquid mixture after the reaction into a gas-liquid separation tank for gas-liquid separation. For example, the temperature of the gas-liquid separator is 10° C. to 20° C. Preferably, the separated hydrogen is circulated into the reactor through a hydrogen circulation pipeline to participate in the reaction.

[0055] Preferably, the method is implemented in a continuous operation mode, with material being fed and discharged simultaneously, and is carried out uninterruptedly within a certain period of time to achieve improved production efficiency.

[0056] Preferably, the mass space velocity of cyclohexyl acetate is 0.2h -1 ~1.0h -1 For example, the mass space velocity of cyclohexyl acetate is 0.2h -1 、0.3h -1 、0.4h -1 , 0.5h -1 , 0.6h -1 、0.7h -1 , 0.8h -1 , 0.9h -1 or 1.0h -1 .

[0057] Preferably, the molar ratio of hydrogen to cyclohexyl acetate is 8: 1 to 16: 1. For example, the molar ratio of hydrogen to cyclohexyl acetate is 8: 1, 9: 1, 10: 1, 11: 1, 12: 1, 13: 1, 14: 1, 15: 1 or 16: 1.

[0058] Preferably, the temperature in the reactor is 120° C. to 180° C. For example, the temperature in the reactor is 120° C., 130° C., 140° C., 150° C., 160° C., 170° C. or 180° C.

[0059] Preferably, the pressure of hydrogen is 3.0 MPa to 6.0 MPa. For example, the pressure of hydrogen is 3.0 MPa, 3.5 MPa, 4.0 MPa, 4.5 MPa, 5.5 MPa or 6.0 MPa.

[0060] Another aspect of the present application provides use of the porous membrane loaded with catalytically active components as described herein in manufacturing the device according to the present application.

[0061] Another aspect of the present application provides use of the porous membrane loaded with catalytically active components described herein in implementing the method described in the present application.

[0062] Example

[0063] To make the technical solution of the present invention clearer, the technical solution of the present invention will be further described below in conjunction with some specific embodiments. The described embodiments are intended to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention.

[0064] The conversion rate and selectivity in the examples of the present application are calculated as follows:

[0065] Cyclohexyl acetate conversion rate = (mass of cyclohexyl acetate charged in feed - mass of cyclohexyl acetate charged in reaction solution) / mass of cyclohexyl acetate charged in feed * 100;

[0066] Cyclohexanol selectivity = moles of cyclohexanol in the reaction solution / moles of cyclohexyl acetate in the feed * 100;

[0067] Ethanol selectivity = moles of ethanol in the reaction solution / moles of cyclohexyl acetate in the feed * 100;

[0068] Source of raw materials: cyclohexyl acetate-Aladdin; hydrogen-Nanjing special gas;

[0069] Experimental equipment manufacturer: Yantai Songling Chemical

[0070] Gas chromatograph: Agilent 8890

[0071] Preparation of porous plate-and-frame flat membrane loaded with catalytically active components

[0072] The porous membrane was placed in the reaction chamber, and after the air inlet pipe was preheated, the catalytic active component precursor gas was introduced for reaction. The carrier gas was high-purity nitrogen at 50 mL / min. In the deposition mode, the pulse time and exposure time of the catalytic active component precursor were set to 1.0 s and 150 s respectively. After 100 cycles, the temperature was lowered to obtain a porous membrane loaded with catalytic active components.

[0073] Example 1

[0074] The reactor is provided with a feed port at the bottom, a gas-liquid discharge port at the top, the bottom feed port is connected to a hydrogen feed pipe and a cyclohexyl acetate feed pipe, the top gas-liquid discharge port is connected to a gas-liquid separator, the top of the gas-liquid separator is connected to the hydrogen feed pipe through a hydrogen circulation pipeline, and the bottom of the gas-liquid separator is connected to the hydrogenation product tank through a hydrogenation liquid pipeline. Four plate-frame flat porous membranes are loaded in the middle section of the reactor, and the porous membrane material is ZrO2 (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.), the porous membrane thickness is 4mm, the porous membrane pore size is 200nm, and the catalytic active component loaded by the porous membrane is Cu (the precursor is copper acetylacetonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.) (loading amount is 5 weight%).

[0075] After the installation is completed, open the valve to introduce hydrogen and cyclohexyl acetate. The gas-liquid mixture flows upward from the bottom of the reactor into the reactor. The hydrogen / cyclohexyl acetate molar ratio is controlled to be 8, and the mass space velocity of cyclohexyl acetate is 0.2h -1 . After being pressurized to 3.0MPa and heated to 120°C, the continuous reaction begins. Hydrogen is quickly broken down by the porous membrane, and reacts quickly with cyclohexyl acetate under the catalytic action of the active component. The gas-liquid mixture after the reaction is taken out from the discharge port and enters the gas-liquid separator for gas-liquid separation. The temperature of the gas-liquid separator is set to 10°C. The separated hydrogen is circulated back to the reactor to participate in the reaction; the liquid phase enters the hydrogenation product tank to obtain a mixed hydrogenation product. The mixed hydrogenation product was analyzed by gas chromatography to calculate the conversion rate and selectivity. The results obtained are: cyclohexyl acetate conversion rate 99.86%, cyclohexanol selectivity 98.23%, ethanol selectivity 97.57%, cyclohexane selectivity 1.63%, cyclohexyl ether selectivity 0.28%.

[0076] Example 2

[0077] The reactor is provided with a feed port at the bottom, a gas-liquid discharge port at the top, the bottom feed port is connected to a hydrogen feed pipe and a cyclohexyl acetate feed pipe, the top gas-liquid discharge port is connected to a gas-liquid separator, the top of the gas-liquid separator is connected to the hydrogen feed pipe through a hydrogen circulation pipeline, and the bottom of the gas-liquid separator is connected to the hydrogenation product tank through a hydrogenation liquid pipeline. Two plate-frame flat porous membranes are loaded in the middle section of the reactor, and the porous membrane material is Al2O3 (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.), the porous membrane thickness is 4mm, the porous membrane pore size is 50nm, and the catalytic active component of the porous membrane load is Zn (the precursor is zinc acetylacetonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.) (loading amount is 5 weight %).

[0078] After the installation is completed, open the valve to introduce hydrogen and cyclohexyl acetate. The gas-liquid mixture flows upward from the bottom of the reactor into the reactor. The hydrogen / cyclohexyl acetate molar ratio is controlled to be 12 and the mass space velocity of cyclohexyl acetate is 0.6h -1. After being pressurized to 6.0MPa and heated to 160°C, the continuous reaction begins. Hydrogen is quickly broken down by the porous membrane, and reacts quickly with cyclohexyl acetate under the catalytic action of the active component. The gas-liquid mixture after the reaction is taken out from the discharge port and enters the gas-liquid separator for gas-liquid separation. The temperature of the gas-liquid separator is set to 15°C. The separated hydrogen is circulated back to the reactor to participate in the reaction; the liquid phase enters the hydrogenation product tank to obtain a mixed hydrogenation product. The mixed hydrogenation product was analyzed by gas chromatography to calculate the conversion rate and selectivity. The results obtained are: cyclohexyl acetate conversion rate 98.17%, cyclohexanol selectivity 97.19%, ethanol selectivity 96.47%, cyclohexane selectivity 1.45%, cyclohexyl ether selectivity 1.39%.

[0079] Example 3

[0080] The reactor is provided with a feed port at the bottom, a gas-liquid discharge port at the top, the bottom feed port is connected to a hydrogen feed pipe and a cyclohexyl acetate feed pipe, the top gas-liquid discharge port is connected to a gas-liquid separator, the top of the gas-liquid separator is connected to the hydrogen feed pipe through a hydrogen circulation pipeline, and the bottom of the gas-liquid separator is connected to a hydrogenation product tank through a hydrogenation liquid pipeline. A plate-frame flat porous membrane is loaded in the middle section of the reactor, the porous membrane material is ZrO2 (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.), the porous membrane thickness is 4mm, the porous membrane pore size is 50nm, and the catalytic active component loaded by the porous membrane is Zn (the precursor is zinc acetylacetonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.) (loading amount is 5 weight %).

[0081] After the installation is completed, open the valve to introduce hydrogen and cyclohexyl acetate. The gas-liquid mixture flows upward from the bottom of the reactor into the reactor. The hydrogen / cyclohexyl acetate molar ratio is controlled to be 14 and the mass space velocity of cyclohexyl acetate is 1.0 h -1 . After being pressurized to 5.0MPa and heated to 140°C, the continuous reaction begins. Hydrogen is quickly broken down by the porous membrane, and reacts quickly with cyclohexyl acetate under the catalytic action of the active component. The gas-liquid mixture after the reaction is taken out from the discharge port and enters the gas-liquid separator for gas-liquid separation. The temperature of the gas-liquid separator is set to 20°C. The separated hydrogen is circulated back to the reactor to participate in the reaction; the liquid phase enters the hydrogenation product tank to obtain a mixed hydrogenation product. The mixed hydrogenation product was analyzed by gas chromatography to calculate the conversion rate and selectivity. The results obtained are: cyclohexyl acetate conversion rate 95.74%, cyclohexanol selectivity 97.35%, ethanol selectivity 94.33%, cyclohexane selectivity 2.01%, cyclohexyl ether selectivity 2.57%.

[0082] Example 4

[0083] The reactor is provided with a feed port at the bottom, a gas-liquid discharge port at the top, the bottom feed port is connected to a hydrogen feed pipe and a cyclohexyl acetate feed pipe, the top gas-liquid discharge port is connected to a gas-liquid separator, the top of the gas-liquid separator is connected to the hydrogen feed pipe through a hydrogen circulation pipeline, and the bottom of the gas-liquid separator is connected to the hydrogenation product tank through a hydrogenation liquid pipeline. The reactor is loaded with 3 plate-frame flat porous membranes in the middle section, the porous membrane material is Al2O3 (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.), the porous membrane thickness is 4mm, the porous membrane pore size is 1000nm, and the catalytic active component of the porous membrane load is Cu (the precursor is copper acetylacetonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.) (loading amount is 5 weight %).

[0084] After the installation is completed, open the valve to introduce hydrogen and cyclohexyl acetate. The gas-liquid mixture flows upward from the bottom of the reactor into the reactor. The hydrogen / cyclohexyl acetate molar ratio is controlled to be 16 and the mass space velocity of cyclohexyl acetate is 0.8 h -1 . After being pressurized to 4.0MPa and heated to 180°C, the continuous reaction begins. Hydrogen is quickly broken down by the porous membrane, and reacts quickly with cyclohexyl acetate under the catalytic action of the active component. The gas-liquid mixture after the reaction is taken out from the discharge port and enters the gas-liquid separator for gas-liquid separation. The temperature of the gas-liquid separator is set to 15°C. The separated hydrogen is circulated back to the reactor to participate in the reaction; the liquid phase enters the hydrogenation product tank to obtain a mixed hydrogenation product. The mixed hydrogenation product was analyzed by gas chromatography to calculate the conversion rate and selectivity. The results obtained are: cyclohexyl acetate conversion rate 98.05%, cyclohexanol selectivity 95.19%, ethanol selectivity 94.47%, cyclohexane selectivity 2.73%, cyclohexyl ether selectivity 2.51%.

[0085] Comparative Example 1

[0086] On the basis of Example 1, the catalyst was filled in a fixed bed reactor in the form of particles, and other conditions were kept the same as those in Example 1, and the loading amount of the active component was also kept the same, and the reaction was carried out in gas-liquid co-flow under the same conditions. The results obtained were: cyclohexyl acetate conversion rate of 94.65%, cyclohexanol selectivity of 96.87%, ethanol selectivity of 95.32%, cyclohexane selectivity of 2.34%, and cyclohexyl ethyl ether selectivity of 1.12%.

[0087] It can be seen from the comparison between Comparative Example 1 and Example 1 that, compared with the catalyst filled in particle form, the porous membrane loaded with catalytically active components is used to produce cyclohexanol by hydrogenation of cyclohexyl acetate, and the hydrogen is well dispersed, the utilization rate is high, the gas-liquid mass transfer efficiency is improved, and the conversion rate of cyclohexyl acetate and the selectivity of cyclohexanol are improved.

[0088] Comparison results of gas-liquid flow direction

[0089] Based on Example 1, the results of different gas-liquid flow patterns were compared through further Examples 5-6. Except for the different gas-liquid flow patterns, other conditions of Examples 5-6 were the same as those of Example 1. The results are summarized in Table 1 below:

[0090] Table 1

[0091]

[0092] From the results in the above table, it can be seen that the cyclohexyl acetate conversion rate and cyclohexanol selectivity obtained by adopting the gas-liquid co-current upward mode are higher than those of the other two modes. Without being limited by theory, it is believed that the gas-liquid co-current upward mode is more conducive to efficient contact between the gas and liquid phases.

[0093] Membrane pore size

[0094] Based on Example 1, the results of different porous membrane pore sizes were compared through further Examples 7-9. Except for the different porous membrane pore sizes, the other conditions of Examples 7-9 were the same as those of Example 1. The results are summarized in Table 2 below:

[0095] Table 2

[0096]

[0097] From the results in the above table, it can be seen that a porous membrane with a pore size that is too large will affect the contact and mass transfer between the gas and liquid phases, resulting in reduced conversion rate and selectivity.

[0098] Plate and frame flat porous membrane quantity

[0099] Based on Example 1, the results of different numbers of plate-frame flat porous membranes were compared through further Examples 10-11. Except for the different numbers of plate-frame flat porous membranes, the other conditions of Examples 10-11 were the same as those of Example 1, and the total loading amount of the active component remained unchanged. The results are summarized in Table 3 below:

[0100] Table 3

[0101]

[0102] Active ingredients

[0103] Based on Example 1, the results of different catalytic active components were compared through further Examples 12-13. Except for the different active components loaded, the other conditions of Examples 12-13 were the same as those of Example 1. The results are summarized in Table 4 below:

[0104] Table 4

[0105]

[0106] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A device for producing cyclohexanol by hydrogenating cyclohexyl acetate, comprising: A reactor, the reactor comprising a feed inlet, a gas-liquid discharge port and a porous membrane, wherein the porous membrane is loaded with catalytically active components; a hydrogen feed pipe connected to the feed port of the reactor; and A cyclohexyl acetate feed pipe connected to the feed port of the reactor.

2. The device according to claim 1, wherein: The reactor is gas-liquid co-flowing to the upper reactor; Preferably, the feed inlet is arranged at the bottom of the reactor, the porous membrane is loaded in the middle section of the reactor, and the gas-liquid discharge port is arranged at the top of the reactor.

3. The device according to any one of the preceding claims, further comprising a gas-liquid separator connected to the gas-liquid discharge port of the reactor; Preferably, the device further comprises a hydrogen circulation pipeline connecting the gas-liquid separator to the feed port of the reactor or the hydrogen feed pipe.

4. A device as claimed in any one of the preceding claims, wherein: Preferably, the pore size of the porous membrane is 50 nm to 2000 nm; Preferably, the porous membrane is a plate-and-frame flat membrane; Preferably, the number of the porous membranes is one or more, for example, 1, 2, 3, 4, 5, 6, 7; Preferably, the material of the porous membrane includes one or any combination of silicon oxide, aluminum oxide and zirconium oxide; Preferably, the thickness of the porous membrane is 0.1 to 10 mm, or 1 to 6 mm, or 3 to 5 mm; Preferably, the catalytically active component comprises one or any combination of Cu, Zn and Fe; Preferably, the catalytically active components are loaded onto the porous membrane by atomic vapor deposition.

5. The apparatus of any one of the preceding claims, further comprising a hydrogen source, a cyclohexyl acetate storage tank, and a hydrogenation product tank.

6. A method for producing cyclohexanol using the device according to any one of claims 1 to 5, the method comprising at least: Feeding hydrogen and cyclohexyl acetate into a reactor equipped with a porous membrane, allowing the hydrogen and cyclohexyl acetate to pass through the porous membrane for a hydrogenation reaction, wherein the porous membrane is loaded with a catalytically active component; Preferably, hydrogen and cyclohexyl acetate are passed through the porous membrane in a co-current flow upward.

7. The method according to claim 6, further comprising introducing the gas-liquid mixture after the reaction into a gas-liquid separation tank for gas-liquid separation; Preferably, the separated hydrogen is circulated into the reactor to participate in the reaction; Preferably, the temperature of the gas-liquid separator is 10°C to 20°C.

8. The method according to claim 6 or 7, wherein: Preferably, the method is carried out in a continuous manner; Preferably, the mass space velocity of cyclohexyl acetate is 0.2h -1 ~1.0h -1 ; Preferably, the hydrogen / cyclohexyl acetate molar ratio is 8:1 to 16:1; Preferably, the temperature in the reactor is 120°C to 180°C; Preferably, the pressure of hydrogen is 3.0 MPa to 6.0 MPa.

9. Use of a porous membrane loaded with catalytically active components in the manufacture of a device according to any one of claims 1 to 5.

10. Use of a porous membrane loaded with catalytically active components in the method according to any one of claims 6 to 8.

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