Electrochemical organic hydrogenation reaction device

Abstract

The invention provides an electrochemical organic hydrogenation reaction device, and relates to the field of electrochemical reaction devices. The electrochemical organic hydrogenation reaction device comprises a hydrogenation reaction mechanism and a circulating feeding mechanism, the hydrogenation reaction mechanism comprises two end plates, a collector plate and an electric reaction tank stack, and the two end plates are arranged at an interval; the electric reaction tank pile and the collector plates are located between the two end plates, and the collector plates are arranged at the two ends of the electric reaction tank pile; the electric reaction tank stack comprises at least one electric reaction tank, and the electric reaction tank is provided with an anode flow channel and a cathode flow channel; the circulating feeding mechanism comprises a driving part and a liquid storage tank, the liquid storage tank is communicated with the end plate through a pipeline, the driving part is installed on the liquid storage tank or the pipeline and used for driving a reaction solution in the liquid storage tank to flow through the cathode flow channel and then be recycled, and the anode flow channel is used for gas to flow through. The electrochemical organic hydrogenation reaction device provided by the invention solves the technical problems of non-uniform reactant distribution, low current density and poor stability when an electrochemical reactor is applied to hydrogenation reaction.

Description

Technical Field

[0001] The present application relates to the field of electrochemical reaction devices, and in particular, to an electrochemical organic hydrogenation reaction device. Background Art

[0002] As an emerging alternative technology to thermal catalytic hydrogenation, electrocatalytic hydrogenation technology can realize hydrogenation conversion reactions under mild conditions such as room temperature and pressure. Combined with the green hydrogen electrochemical engineering technology with green premium characteristics, it is expected to bring revolutionary changes to organic synthesis with high energy consumption and high precious metal usage. In order to achieve efficient and practical organic synthesis pathways, electrochemical reaction devices use a stack structure to reduce internal resistance, increase active area, and accelerate reaction rates. However, existing electrochemical reactor stacks have the following limitations: 1) The number and area of ​​the cell stack can theoretically continue to increase, but the simple increase in cells and area will cause uneven distribution of reactants in the reaction device, resulting in easy failure of stack materials and heat management; 2) Existing electrochemical reactors have low current density, many side reactions, and poor stability for hydrogenation reactions, which cannot meet the needs of actual applications. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide an electrochemical organic hydrogenation reaction device to alleviate the technical problems existing in the prior art of uneven distribution of reactants, low current density and poor stability when the electrochemical reactor is applied to the hydrogenation reaction.

[0004] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0005] In a first aspect, the electrochemical organic hydrogenation reaction device provided by the present invention comprises a hydrogenation reaction mechanism and a circulating feeding mechanism;

[0006] The hydrogenation reaction mechanism comprises an end plate, a current collecting plate and an electric reactor stack, wherein two end plates are provided and the two end plates are arranged at intervals; the electric reactor stack and the current collecting plate are both located between the two end plates, and the current collecting plate is provided at both ends of the electric reactor stack; the electric reactor stack comprises at least one electric reactor, and the electric reactor has an anode flow channel and a cathode flow channel;

[0007] The circulating feeding mechanism includes a driving member and a liquid storage tank, the liquid storage tank is connected to the end plate through a pipeline, the driving member is installed on the liquid storage tank or the pipeline, and is used to drive the reaction solution in the liquid storage tank to flow through the cathode flow channel and then be recovered, and the anode flow channel is used for gas to flow through.

[0008] Furthermore, the anode flow channel and the cathode flow channel include at least one of a serpentine flow channel, a radial flow channel, a grid flow channel and a bionic flow channel.

[0009] Furthermore, the electric reaction cell comprises an anode electrode, a cathode electrode and a diaphragm, wherein the anode electrode and the cathode electrode are respectively located on both sides of the diaphragm;

[0010] A bipolar plate is provided on the side of the anode electrode facing away from the diaphragm and opposite to the anode side of the bipolar plate; or opposite to one of the current collecting plates;

[0011] The bipolar plate is provided on the side of the cathode electrode facing away from the diaphragm and opposite to the cathode side of the bipolar plate; or opposite to another current collecting plate;

[0012] The anode side is provided with the anode flow channel, and the cathode side is provided with the cathode flow channel.

[0013] Furthermore, the anode electrode is loaded with a transition metal catalyst, and the cathode electrode or the diaphragm is loaded with a carbon-based catalyst.

[0014] Furthermore, the transition metal catalyst includes at least one of metals, alloys, oxides and hydroxides containing elements such as copper and nickel; the carbon-based catalyst includes at least one of carbon black, graphene oxide and graphite.

[0015] Furthermore, the material of the anode electrode and the cathode electrode includes at least one of a gas diffusion layer, porous carbon, graphite and foamed metal.

[0016] Furthermore, the cathode electrode and the anode electrode are both configured as porous hydrophobic gas diffusion electrodes.

[0017] Furthermore, the membrane is configured as a polyolefin membrane, a proton exchange membrane or a nanocomposite membrane.

[0018] Furthermore, the reaction solution includes a mixed solution of a reaction substrate and an organic solvent; the organic solvent is one or more of n-hexane, cyclohexane, nitrogen, nitrogen-dimethylformamide, xylene, trimethylbenzene, pentane, hexane, octane, dichloromethane, cyclohexanone, toluene, cyclohexanone, methanol, ethanol, n-butanol, acetonitrile, pyridine, and phenol.

[0019] Furthermore, the hydrogenation reaction mechanism further includes an insulating plate, and the insulating plate is located between the end plate and the current collecting plate.

[0020] Based on the above technical solutions, the technical effects that can be achieved by the present invention are analyzed as follows:

[0021] The electrochemical organic hydrogenation reaction device provided by the present invention includes a hydrogenation reaction mechanism and a circulating feeding mechanism; the hydrogenation reaction mechanism includes an end plate, a current collecting plate and an electric reactor stack, two end plates are provided, and the two end plates are arranged at intervals; the electric reactor stack and the current collecting plate are both located between the two end plates, and the two ends of the electric reactor stack are provided with current collecting plates; the electric reactor stack includes at least one electric reactor, and the electric reactor has an anode flow channel and a cathode flow channel; the circulating feeding mechanism includes a driving member and a liquid storage tank, the liquid storage tank is connected to the end plate through a pipeline, the driving member is installed on the liquid storage tank or the pipeline, and is used to drive the reaction solution in the liquid storage tank to flow through the cathode flow channel for recovery, and the anode flow channel is used for gas to flow through. The circulating feeding mechanism realizes the recovery and circulation of the reaction solution, and the design of the cathode and anode gas-liquid co-recovery reduces the osmotic pressure between the two poles to avoid the loss of yield; the electric reactor structure improves the hydrogenation reaction rate and is easy to enlarge, and has industrial prospects; the anode flow channel and the cathode flow channel make the reactants evenly distributed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of an electrochemical organic hydrogenation reaction device provided in an embodiment of the present application;

[0024] Figure 2 A schematic diagram of the structure of the hydrogenation reaction mechanism in the electrochemical organic hydrogenation reaction device provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of the decomposition of an electric reaction cell in an electrochemical organic hydrogenation reaction device provided in an embodiment of the present application;

[0026] Figure 4 A schematic diagram of the structure of an electric reaction cell in an electrochemical organic hydrogenation reaction device provided in an embodiment of the present application;

[0027] Figure 5 A simulation diagram of the multi-channel radial flow channels of the bipolar plate in the electrochemical organic hydrogenation reaction device provided in an embodiment of the present application.

[0028] icon:

[0029] 1-hydrogenation reaction mechanism; 11-end plate; 12-current collecting plate; 13-electric reaction cell; 131-bipolar plate; 132-anode electrode; 133-cathode electrode; 134-diaphragm; 135-catalytic layer; 136-sealing gasket; 14-insulating plate;

[0030] 2-Circulation feeding mechanism. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0033] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" 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 direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0034] The electrochemical organic hydrogenation reaction device provided by the embodiment of the present invention includes a hydrogenation reaction mechanism 1 and a circulating feeding mechanism 2; the hydrogenation reaction mechanism 1 includes an end plate 11, a current collecting plate 12 and an electric reaction cell stack, two end plates 11 are provided, and the two end plates 11 are arranged at intervals; the electric reaction cell stack and the current collecting plate 12 are both located between the two end plates 11, and the current collecting plates 12 are provided at both ends of the electric reaction cell stack; the electric reaction cell stack includes at least one electric reaction cell 13, and the electric reaction cell 13 has an anode flow channel and a cathode flow channel; the circulating feeding mechanism 2 includes a driving member and a liquid storage tank, the liquid storage tank is connected to the end plate 11 through a pipeline, the driving member is installed on the liquid storage tank or the pipeline, and is used to drive the reaction solution in the liquid storage tank to flow through the cathode flow channel and then be recovered, and the anode flow channel is used for gas to flow through.

[0035] Specifically, see Figures 1 to 4, the end plate 11 is arranged as the outermost side of the hydrogenation reaction mechanism 1. The circulating feeding mechanism 2 drives the reaction solution to flow out of the liquid storage tank into the hydrogenation reaction mechanism 1, and the reaction solution is recycled after passing through the cathode flow channel and the cathode electrode 133 in the hydrogenation reaction mechanism 1 in turn. The gas enters the hydrogenation reaction mechanism 1 and passes through the anode flow channel and the anode electrode 132 in turn. The current collecting plate 12 is arranged between the end plates 11 or fixed on the side of the anode electrode 132 and the cathode electrode 133 close to the end plate 11. The driving member is arranged as a peristaltic pump. The circulating feeding mechanism 2 also includes a gas control member, which is installed in the liquid storage tank or the pipeline; the gas control member is a gas flow meter.

[0036] The circulating feeding mechanism 2 realizes the recovery and circulation of the reaction solution. The design of joint recovery of cathode and anode gas and liquid reduces the osmotic pressure between the two electrodes to avoid yield loss; the stack structure improves the hydrogenation reaction rate and is easy to scale up, with industrial prospects; the anode flow channel and the cathode flow channel make the reactants evenly distributed.

[0037] In an optional solution of the embodiment of the present invention, the anode flow channel and the cathode flow channel include at least one of a serpentine flow channel, a radial flow channel, a grid flow channel and a bionic flow channel.

[0038] Specifically, in this embodiment, the anode flow channel and the cathode flow channel are configured as serpentine flow channels, which can effectively solve the problem of uneven distribution of reactants in the electrochemical reaction device and improve the mass transfer and liquid transfer rate of the electrochemical organic hydrogen reaction device. Of course, the anode flow channel and the cathode flow channel are configured as one or more of parallel flow channels, direct flow channels, interdigital flow channels and spiral flow channels, which should also be within the protection scope of the embodiments of the present invention.

[0039] In an optional solution of the embodiment of the present invention, the electric reaction cell 13 includes an anode electrode 132, a cathode electrode 133 and a diaphragm 134, wherein the anode electrode 132 and the cathode electrode 133 are respectively located on both sides of the diaphragm 134; a bipolar plate 131 is provided on the side of the anode electrode 132 away from the diaphragm 134, and is opposite to the anode side of the bipolar plate 131; or, is opposite to one of the current collectors; a bipolar plate 131 is provided on the side of the cathode electrode 133 away from the diaphragm 134, and is opposite to the cathode side of the bipolar plate 131; or, is opposite to another current collector. An anode flow channel is provided on the anode side of the bipolar plate 131, and a cathode flow channel is provided on the cathode side.

[0040] Specifically, a sealing gasket 136 is provided between the diaphragm 134 and the cathode electrode 133, and a sealing gasket 136 is provided between the diaphragm 134 and the anode electrode 132; the sealing gasket 136 plays a sealing role. Two adjacent electric reaction cells 13 share a bipolar plate 131, that is, the two adjacent electric reaction cells 13 use the cathode side and the anode side of the same bipolar plate 131 respectively. Figure 2, from left to right, the first electric reaction cell 13 includes an anode electrode 132, a cathode electrode 133, a diaphragm 134 and the cathode side of the bipolar plate 131, wherein the diaphragm 134 is located between the anode electrode 132 and the cathode electrode 133, the side of the anode electrode 132 away from the diaphragm 134 is opposite to the first current collecting plate 12, and the side of the cathode electrode 133 away from the diaphragm 134 is opposite to the cathode side of the bipolar plate 131; the second electric reaction cell 13 includes the anode side of the bipolar plate 131 , anode electrode 132, cathode electrode 133, diaphragm 134 and the cathode side of the bipolar plate 131, and are stacked in the order of the anode side of the bipolar plate 131, the anode electrode 132, the diaphragm 134, the cathode electrode 133 and the cathode side of the bipolar plate 131; and so on, the last electric reaction cell 13 includes the anode side of the bipolar plate 131, the anode electrode 132, the cathode electrode 133 and the diaphragm 134, wherein the cathode electrode 133 is opposite to the second current collecting plate 12.

[0041] The bipolar plate 131 , the anode electrode 132 , the cathode electrode 133 and the diaphragm 134 form an electric reaction cell 13 to realize a hydrogenation reaction.

[0042] In an optional solution of the embodiment of the present invention, the anode electrode 132 is loaded with a transition metal catalyst, and the cathode electrode 133 or the diaphragm 134 is loaded with a carbon-based catalyst.

[0043] In an optional scheme of an embodiment of the present invention, the transition metal catalyst includes at least one of metals, alloys, oxides and hydroxides containing elements such as copper and nickel; the carbon-based catalyst includes at least one of carbon black, graphene oxide and graphite.

[0044] In the optional scheme of the embodiment of the present invention, the loading method of the transition metal catalyst is electrochemical deposition, spraying, impregnation or ion exchange; the loading range of the metal in the microporous layer of the transition metal catalyst is 1-3 mg / cm 2 .

[0045] Specifically, the metal loading in the microporous layer of the transition metal catalyst is set to 1 mg / cm 2 , 2mg / cm 2 or 3mg / cm 2 .

[0046] In the optional scheme of the embodiment of the present invention, the carbon-based catalyst is loaded by electrochemical deposition, spraying, impregnation or ion exchange; the platinum loading range in the microporous layer of the carbon-based catalyst is 0.1-0.4 mg / cm 2 .

[0047] Specifically, the platinum loading in the carbon-based catalyst microporous layer was set to 0.1 mg / cm 2 , 0.2mg / cm 2 or 0.4mg / cm2 .

[0048] In an optional solution of the embodiment of the present invention, the material of the anode electrode 132 and the cathode electrode 133 includes at least one of a gas diffusion layer, porous carbon, graphite and foam metal.

[0049] In an optional solution of the embodiment of the present invention, the cathode electrode 133 and the anode electrode 132 are both configured as porous hydrophobic gas diffusion electrodes.

[0050] Specifically, the use of porous hydrophobic gas diffusion electrodes in the electrochemical organic hydrogenation device greatly shortens the gas diffusion distance compared to the H-type electrolytic cell, and the current density can reach 500mA / cm 2 Compared with the H-type electrolytic cell and the single electrolytic cell, which have the phenomenon of gas enrichment on the electrode surface, the electrochemical organic hydrogenation reaction device adopts a flow-type electrolyzer to improve the bubble density phenomenon, and the bubble enrichment phenomenon on the electrode surface is improved by coating the surface of the gas diffusion electrode with hydrophilic and hydrophobic materials and alkali modification. The electrochemical organic hydrogenation reaction device is mainly composed of a porous hydrophobic gas diffusion layer, a cathode chamber, an anode chamber and an exchange membrane. H2 continuously passes through the porous hydrophobic gas diffusion layer and reacts with the catalyst and the electrolyte at the gas-liquid-solid three-phase interface, which effectively solves the problem of low mass transfer efficiency of the H-type electrolyzer.

[0051] In an optional solution of the embodiment of the present invention, a voltage is applied to the electrochemical organic hydrogenation reaction device to change the flow field distribution to accelerate the hydrogenation reaction rate of the organic compound.

[0052] In an optional solution of the embodiment of the present invention, the materials of the end plate 11 and the current collecting plate 12 include metal materials and stainless steel materials, and the material of the bipolar plate includes at least one of stainless steel materials, titanium metal and titanium alloy.

[0053] In an optional solution of the embodiment of the present invention, the surface of the end plate 11 and / or the current collecting plate 12 is provided with a coating.

[0054] Specifically, the surfaces of the end plate 11 and the current collecting plate 12 are both provided with a coating, and the coating prevents the end plate 11 and the current collecting plate 12 from being corroded by the reaction solution. Furthermore, the end plate 11 and the current collecting plate 12 are coated by surface treatment.

[0055] In an optional solution of the embodiment of the present invention, the membrane 134 is configured as a polyolefin membrane, a proton exchange membrane or a nanocomposite membrane.

[0056] In an optional scheme of an embodiment of the present invention, the reaction solution includes a mixed solution of a reaction substrate and an organic solvent; the organic solvent is one or more of n-hexane, cyclohexane, nitrogen, nitrogen-dimethylformamide, xylene, trimethylbenzene, pentane, hexane, octane, dichloromethane, cyclohexanone, toluene, cyclohexanone, methanol, ethanol, n-butanol, acetonitrile, pyridine, and phenol.

[0057] In an optional solution of the embodiment of the present invention, the hydrogenation reaction mechanism 1 further includes an insulating plate 14, and the insulating plate 14 is located between the end plate 11 and the current collecting plate 12. The insulating plate 14 can prevent the hydrogenation reaction mechanism 1 from short-circuiting.

[0058] In an optional solution of the embodiment of the present invention, the hydrogenation reaction mechanism 1 is assembled by screws.

[0059] Specifically, the hydrogenation reaction mechanism 1 is assembled by applying pressure through screws, and the assembly method is simple.

[0060] The present invention has no special restrictions on the sources of all raw materials. Unless otherwise specified, they are all conventional products that can be obtained commercially.

[0061] The following is an example of the application of the electrochemical organic hydrogenation reaction device:

[0062] In the following embodiments, the anode catalyst used in the electrochemical organic hydrogenation reaction device is a platinum-carbon catalyst (platinum loading 3%), and the cathode nickel-based catalyst is a nickel-carbon catalyst (nickel loading 30%). The electrochemical organic hydrogenation reaction device includes a hydrogenation reaction mechanism 1 and a circulating feeding mechanism 2. In this embodiment, the circulating feeding mechanism 2 uses a peristaltic pump as a power drive device. The circulating feeding mechanism 2 is connected to the hydrogenation reaction mechanism 1 by a pipeline.

[0063] Example 1

[0064] In this embodiment, the reaction area of ​​the hydrogenation reaction mechanism 1 is 1 cm×1 cm, and each component is assembled by applying pressure with screws. The hydrogenation reaction mechanism 1 includes an electric reaction cell 13, and is connected to the circulating feed mechanism 2, with a total active area of ​​1×1 cm 2 The electric reaction cell 13 includes a diaphragm 134, and the two sides of the diaphragm 134 are respectively pressed by the anode electrode 132, the cathode electrode 133 and the catalyst layer 135 through the sealing gasket 136. Such a setting can increase the electrochemical hydrogenation reaction rate, and the structure is easy to scale up and has industrial prospects.

[0065] In this embodiment, a mixed solution of 10 ml of ethanol, 1 mmol of an aromatic azo compound and 0.4 mmol of tetrabutylammonium tetrafluoroborate is used as an organic solvent for hydrogenation reaction. The circulating feeding mechanism 2 includes a liquid storage tank and a driving member, and the liquid storage tank is used to place the reaction solution. The bipolar plate 131 is made of stainless steel, and the diaphragm 134 is made of a proton exchange membrane with a pore size of 0.45 μm. The anode electrode 132 is made of a gas diffusion layer with a thickness of 0.1 mm and a porosity of 50%. Platinum carbon is used as a catalyst and is loaded on the surface of the diffusion layer by spraying. The loading range of platinum carbon is 0.1-0.4 mg / cm 2The platinum-based catalyst used in the anode electrode 132 can improve the catalytic activity of the reaction of aromatic azo compounds, thereby improving the yield and yield of the product; the cathode electrode 133 is made of pure nickel foam, with a thickness of 0.2 mm and a porosity of 95%. On this basis, the feeding device is heated and stirred at a constant temperature of 35°C. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to the electrochemical workstation for hydrogenation experiments. The external voltage applied to the hydrogenation reaction mechanism 1 is -1V, so that the reaction occurs and the reaction solution is recovered at the same time. With this arrangement, the reaction solution can be recovered, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 60 minutes, the conversion rate of aromatic azo compounds is as high as 99% or more.

[0066] Example 2

[0067] Different from Example 1, N, N-diisopropylethylamine is added in this embodiment, and the specific reaction solution is a mixed solution of 10ml ethanol, 1mmol aromatic azo compound, 0.04mmol N, N-diisopropylethylamine and 0.4mmol tetrabutylammonium tetrafluoroborate. The cathode electrode 133 is made of pure nickel foam, with a thickness of 0.2mm and a porosity of 95%. On this basis, the circulating feeding mechanism 2 is heated and stirred at a constant temperature of 35°C. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to the electrochemical workstation for hydrogenation experiments. The external voltage applied to the hydrogenation reaction mechanism 1 is -1V, so that the reaction occurs and the reaction solution is recovered. In this way, the reaction solution can be recovered, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 60min, the conversion rate of aromatic azo compounds is as high as 99% or more.

[0068] Example 3

[0069] Unlike Example 2, the cathode electrode 133 uses a foam copper catalyst. The reaction solution is a mixed solution of 10ml ethanol, 1mmol aromatic azo compound, 0.04mmol N,N-diisopropylethylamine and 0.4mmol tetrabutylammonium tetrafluoroborate. The cathode electrode 133 is made of pure foam copper with a thickness of 0.8mm and a porosity of 95%. On this basis, the circulating feeding mechanism 2 is heated and stirred at a constant temperature of 35°C. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to the electrochemical workstation for hydrogenation experiments. The external voltage of the hydrogenation reaction mechanism 1 is -1V, so that the reaction occurs and the reaction solution is recovered at the same time. With this arrangement, the reaction solution can be recovered, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 60min, the conversion rate of aromatic azo compounds is as high as 99% or more.

[0070] Example 4

[0071] Different from Example 2, in this example, the surface of the copper foam of the cathode electrode 133 is modified with ammonia. The specific reaction solution is a mixed solution of 10 ml ethanol, 1 mmol aromatic azo compound, 0.04 mmol N, N-diisopropylethylamine and 0.4 mmol tetrabutylammonium tetrafluoroborate. The anode electrode 132 is made of a gas diffusion layer with a thickness of 0.1 mm and a porosity of 50%. A nickel-based carbon material is used as a catalyst and loaded on the surface of the diffusion layer by spraying, and the loading range is 0.1-0.4 mg / cm 2 Between. The platinum-carbon catalyst selected for the anode electrode 132 can increase the reaction rate of the aromatic azo compound, thereby increasing the yield and yield of the product; the cathode electrode 133 is made of foam copper with a thickness of 0.8 mm and a porosity of 95%, and is immersed in ammonia water for 4 hours. On this basis, the circulating feeding mechanism 2 is heated and stirred at a constant temperature of 35°C. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to the electrochemical workstation for the hydrogenation experiment. The hydrogenation reaction mechanism 1 applies an external voltage of -1V, so that the reaction occurs and the reaction solution is recovered at the same time. With this arrangement, the reaction solution can be recovered, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 60 minutes, the conversion rate of aromatic azo compounds is as high as 99% or more.

[0072] Example 5

[0073] Different from Example 4, in this example, the reaction area of ​​the hydrogenation reaction mechanism 1 is 5 cm×5 cm, and each component is assembled by applying pressure with screws. The hydrogenation reaction mechanism 1 is composed of five stacked electric reaction cells and a circulating feed mechanism 2, with a total active area of ​​5×25 cm 2 . In this embodiment, a mixed solution of 50ml ethanol, 5mmol aromatic azo compound, 0.2mmol N,N-diisopropylethylamine and 2mmol tetrabutylammonium tetrafluoroborate is used as an organic solvent for hydrogenation reaction. The circulating feeding mechanism 2 includes a liquid storage tank and a driving part, and the liquid storage tank is used to place the reaction solution. The bipolar plate 131 is made of stainless steel, and the diaphragm 134 is made of a proton exchange membrane with a pore size of 0.45μm. The material of the anode electrode 132 is a gas diffusion layer with a thickness of 0.1mm and a porosity of 50%. Platinum carbon is used as a catalyst and is loaded on the surface of the diffusion layer by spraying. The loading range of platinum carbon is 0.1-0.4mg / cm 2The platinum-based catalyst used in the anode electrode 132 can improve the catalytic activity of the reaction of aromatic azo compounds, thereby improving the yield and yield of the product; the material of the cathode electrode 133 is nickel foam, with a thickness of 0.2 mm and a porosity of 95%, and graphene oxide is loaded on the cathode electrode 133 by a hydrothermal method. The loading amount of the graphene oxide catalyst in the microporous layer is 0.1 mg / L, which can effectively improve the catalytic activity of the reduction reaction of aromatic azo compounds, thereby improving the yield and yield of the product. On this basis, the feeding device is heated and stirred at a constant temperature of 35°C. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to a DC power supply for hydrogenation experiments. The external voltage applied to the hydrogenation reaction mechanism 1 is -8V, so that the reaction occurs and the reaction solution is recovered. In this way, the reaction solution can be recovered, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 20 minutes, the conversion rate of aromatic azo compounds is as high as 99% or more.

[0074] Example 6

[0075] The difference between this embodiment and embodiment 5 is that in this embodiment, the reaction area of ​​the hydrogenation reaction mechanism 1 is 10 cm×10 cm, the hydrogenation reaction mechanism 1 is composed of five stacked electric reaction cells, and is connected to the circulating feeding mechanism 2, and each component is assembled by applying pressure with screws, and the total active area is 5×100 cm 2 The outermost end plate 11 and bipolar plate 131 of the hydrogenation reaction mechanism 1 are made of stainless steel, and the diaphragm 134 is made of a water electrolysis hydrogen production membrane. The anode electrode 132 is made of a gas diffusion layer with a thickness of 0.1 mm and a porosity of 50%. A nickel base is used as a catalyst to be loaded on the surface of the gas diffusion layer by electrodeposition, and the loading amount of the nickel base is 0.4 mg / cm 2 , which can effectively increase the hydrogenation reaction rate of aromatic azo compounds and reduce the occurrence of side reactions. The circulating feeding mechanism 2 transports the reaction solution to the cathode flow channel, and the bipolar plate 131 is connected to a DC power supply for hydrogenation experiments. The external voltage applied to the hydrogenation reaction mechanism 1 is -8V, and the anode flow channel and the cathode flow channel are set as tree-like flow channels. Such a setting can realize the joint recovery of the cathode and anode solutions, thereby reducing the yield loss between the two poles. Under the conditions of this embodiment, when the hydrogenation reaction time is 10min, the conversion rate of aromatic azo compounds is as high as more than 99%.

[0076] Example 7

[0077] The difference between this embodiment and embodiment 6 is that in this embodiment, the reaction area of ​​the hydrogenation reaction mechanism 1 is 10 cm×15 cm, the hydrogenation reaction mechanism 1 is composed of five stacked electric reaction cells, and is connected to the circulating feeding mechanism 2, and each component is assembled by applying pressure with screws, and the total active area is 5×150 cm 2The outermost end plate 11 of the hydrogenation reaction mechanism 1 is made of titanium, and the diaphragm 134 is made of a proton membrane. The anode electrode 132 is made of a gas diffusion layer with a thickness of 0.1 mm and a porosity of 50%. Nickel-based and carbon black are used as catalysts and loaded on the surface of the electrode skeleton by spraying. The nickel loading is 0.4 mg / cm 2 , which can effectively increase the hydrogenation reaction rate of aromatic azo compounds and reduce the occurrence of side reactions. The cathode electrode 133 is made of foam copper with a thickness of 0.2mm and a porosity of 95%. Graphene oxide is loaded on the cathode electrode 133 by a hydrothermal method. The loading amount of graphene oxide catalyst in the microporous layer is 0.1mg / L, which can effectively improve the catalytic activity of the reduction reaction of aromatic azo compounds, thereby improving the yield and yield of the product. The circulating feeding mechanism 2 uses a peristaltic pump as a material conveying device, and ethanol is used as an organic solvent. The anode flow channel and the cathode flow channel are set as radial flow channels, and experimental simulation is carried out using an electrochemical organic hydrogenation reaction device. Through the comparison of experimental simulation data, it is found that when the anode and cathode flow channels are set as serpentine six-channel reaction liquid flow rate of 600mL / min, the simulated flow rate can reach 2.61m / s, and the maximum pressure difference is about 0.3 atmospheres. The anode flow channel and the cathode flow channel are set as radial flow channels for simulation experiments, and it is found that the mass transfer and liquid transfer rate of the radial flow channel is increased by 8 to 10 times. The radial flow channel simulation diagram is as shown in the figure Figure 5 shown.

[0078] The electrochemical organic hydrogenation reaction device provided in the embodiment of the present invention can be applied to the hydrogenation reaction of aromatic azo compounds.

[0079] Working process of electrochemical organic hydrogenation reaction device: prepare a reaction solution before the reaction, and assemble and connect the hydrogenation reaction mechanism 1 and the circulating feeding mechanism 2 in advance; during the reaction, use the circulating feeding mechanism 2 to circulate the reaction solution into the cathode flow channel of the hydrogenation reaction mechanism 1 for reaction, and pass the gas into the anode flow channel of the hydrogenation reaction device for reaction; apply voltage to the hydrogenation reaction mechanism 1, and the voltage range is (-1.0 to -8.0V). Stop the reaction and recover the reaction solution.

[0080] Example 8

[0081] The conversion rate of hydrogenated aromatic azo compounds prepared by the electrochemical organic hydrogenation reaction device in Example 1 is above 99%. The specific steps are as follows:

[0082] (1) Before the reaction, prepare a reaction solution: mix the aromatic azo compound with the ethanol solution in a ratio of 1:10, add tetrabutylammonium tetrafluoroborate and N,N-diisopropylethylamine, and place it in a liquid storage tank.

[0083] (2) The reaction solution in the liquid storage tank was heated to 35°C and stirred at a constant temperature.

[0084] (3) The reaction solution is circulated into the cathode flow channel and the gas is circulated into the anode flow channel using the circulating feeding mechanism 2.

[0085] (4) A voltage is applied to the hydrogenation reaction mechanism 1 and a DC power supply is used for testing.

[0086] (5) Stop the reaction and recover the reaction solution.

[0087] It should be noted that, in the absence of conflict, the features in the embodiments of this application may be combined with each other.

[0088] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electrochemical organic hydrogenation reaction device, characterized in that: include: A hydrogenation reaction mechanism (1) and a circulating feeding mechanism (2); The hydrogenation reaction mechanism (1) comprises an end plate (11), a current collecting plate (12) and an electric reaction cell stack, wherein two end plates (11) are provided, and the two end plates (11) are arranged at intervals; the electric reaction cell stack and the current collecting plate (12) are both located between the two end plates (11), and the current collecting plate (12) is provided at both ends of the electric reaction cell stack; the electric reaction cell stack comprises at least one electric reaction cell (13), and the electric reaction cell (13) has an anode flow channel and a cathode flow channel; The circulating feeding mechanism (2) comprises a driving member and a liquid storage tank, wherein the liquid storage tank is connected to the end plate (11) via a pipeline, and the driving member is installed on the liquid storage tank or the pipeline and is used to drive the reaction solution in the liquid storage tank to flow through the cathode flow channel and then be recovered, and the anode flow channel is used for gas to flow through.

2. The electrochemical organic hydrogenation reaction device according to claim 1, characterized in that: The anode flow channel and the cathode flow channel include at least one of a serpentine flow channel, a radial flow channel, a grid flow channel, and a bionic flow channel.

3. The electrochemical organic hydrogenation reaction device according to claim 1, characterized in that: The electric reaction cell (13) comprises an anode electrode (132), a cathode electrode (133) and a diaphragm (134), wherein the anode electrode (132) and the cathode electrode (133) are respectively located on both sides of the diaphragm (134); A bipolar plate (131) is provided on a side of the anode electrode (132) facing away from the diaphragm (134), and is opposite to the anode side of the bipolar plate (131); or, is opposite to one of the current collecting plates (12); The bipolar plate (131) is provided on a side of the cathode electrode (133) facing away from the diaphragm (134), and is opposite to the cathode side of the bipolar plate (131); or, is opposite to another current collecting plate (12); The anode side is provided with the anode flow channel, and the cathode side is provided with the cathode flow channel.

4. The electrochemical organic hydrogenation reaction device according to claim 3, characterized in that: The anode electrode (132) is loaded with a transition metal catalyst, and the cathode electrode (133) or the separator (134) is loaded with a carbon-based catalyst.

5. The electrochemical organic hydrogenation reaction device according to claim 4, characterized in that: The transition metal catalyst includes at least one of metals, alloys, oxides and hydroxides containing elements such as copper and nickel; the carbon-based catalyst includes at least one of carbon black, graphene oxide and graphite.

6. The electrochemical organic hydrogenation reaction device according to claim 3, characterized in that: The material of the anode electrode (132) and the cathode electrode (133) includes at least one of a gas diffusion layer, porous carbon, graphite and foamed metal.

7. The electrochemical organic hydrogenation reaction device according to claim 3, characterized in that: The cathode electrode (133) and the anode electrode (132) are both configured as porous hydrophobic gas diffusion electrodes.

8. The electrochemical organic hydrogenation reaction device according to claim 3, characterized in that: The diaphragm (134) is configured as a polyolefin diaphragm, a proton exchange membrane or a nanocomposite diaphragm.

9. The electrochemical organic hydrogenation reaction device according to claim 1, characterized in that: The reaction solution comprises a mixed solution of a reaction substrate and an organic solvent; the organic solvent is one or more of n-hexane, cyclohexane, nitrogen, nitrogen-dimethylformamide, xylene, trimethylbenzene, pentane, hexane, octane, dichloromethane, cyclohexanone, toluene, cyclohexanone, methanol, ethanol, n-butanol, acetonitrile, pyridine, and phenol.

10. The electrochemical organic hydrogenation reaction device according to any one of claims 1 to 9, characterized in that: The hydrogenation reaction mechanism (1) further comprises an insulating plate (14), wherein the insulating plate (14) is located between the end plate (11) and the current collecting plate (12).

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