CN217378044U - Novel high-temperature electrochemical urea electrolytic cell device - Google Patents

Abstract

The utility model provides a novel high-temperature electrochemical urea-producing electrolytic cell device, which utilizes nitrogen gas and carbon dioxide to electrochemically directly couple to prepare urea under heating conditions, and belongs to the technical field of electrochemical and electrocatalytic reaction equipment. The device includes a cathode plate, a cathode flow channel, an anode plate, an anode flow channel, a cathode gas diffusion layer, a cathode catalyst layer, a common gasket, a cathode electrolyte chamber gasket, a cathode electrolyte layer, a solid electrolyte layer, an anode catalyst layer, Anode gas diffusion layer, heating system, high temperature compression screw, electrolytic cell incubator. The high-temperature electrochemical urea electrolytic cell device with the above structure has the characteristics of reasonable design structure, simple assembly process, high urea conversion rate, low material cost and long service life, which can realize large-scale urea production, greatly improve production efficiency, and meet the needs of production needs.

Description

A new type of high temperature electrochemical urea electrolytic cell device

technical field

The utility model belongs to the technical field of electrochemical and electrocatalytic reaction equipment, in particular to a novel high-temperature electrochemical urea-producing electrolytic cell device.

Background technique

Urea, also known as urea and carbonamide, with the chemical formula CO(NH ₂ ) ₂ , is an important raw material in the chemical industry. Urea is relatively stable, easy to store, easy to use, and has little damage to soil. It is the fertilizer nitrogen source with the highest nitrogen content. However, the current industrial production of urea uses carbon dioxide and ammonia as raw materials, and the industrial production of ammonia is carried out under high temperature and high pressure, resulting in high energy consumption and dangerous operation. In addition, industrially utilizes carbon dioxide and ammonia to produce urea, first generates ammonium carbamate, and then forms urea through dehydration, and this reaction condition is also high temperature and high pressure, and energy consumption is higher, and its reaction equation is:

2NH ₃ +CO ₂ →NH ₂ COONH ₄ →CO(NH ₂ ) ₂ +H ₂ O

The use of electrical energy to synthesize chemicals with high added value through electrolysis technology is of great significance for the sustainable development of human society. At present, it has been reported that the electrochemical reduction of nitrogen and carbon dioxide to prepare urea at room temperature is a relatively new method. However, this method usually adopts an H-cell (H-cell) at room temperature. Nitrogen and carbon dioxide gas are passed into the catholyte solution, and the dissolved nitrogen and carbon dioxide are used for the reaction. However, this method of using H-cell and using dissolved gas has low reaction efficiency and low urea yield. The most important reasons include: first, the activation and conversion of nitrogen at room temperature is difficult; second, only dissolved carbon dioxide and The nitrogen reaction leads to difficulty in mass transfer; the third is the serious hydrogen evolution in the cathode side reaction.

Therefore, a new type of high-temperature electrochemical urea electrolytic cell device is sought, which activates nitrogen and carbon dioxide in situ at a relatively high temperature, and uses gas phase to directly couple to prepare urea. Overpotential is the future focus of researchers in the field.

Utility model content

In view of this, in view of the shortcomings of the existing room temperature H-cell electrochemical urea preparation technology, the utility model provides a novel high temperature electrochemical urea preparation electrolytic cell device, which can utilize the direct coupling of nitrogen and carbon dioxide at higher temperatures , to achieve large-scale production of urea. The electrolytic cell assembly method is simple, the cost is low, the reaction efficiency is remarkable, and the electrolytic cell has a good application prospect in industrial production in the future.

In order to solve the above technical problems, the technical scheme of the present utility model is: a novel high-temperature electrochemical urea electrolytic cell device, comprising a cathode plate, a cathode flow channel, an anode plate, an anode flow channel, a cathode gas diffusion layer, a cathode catalyst layer, Common gasket, catholyte chamber gasket, catholyte layer, solid electrolyte layer, anode catalyst layer, anode gas diffusion layer, heating system, high temperature compression screw, electrolytic cell incubator.

As a new type of high-temperature electrochemical urea electrolytic cell device, the cathode plate and anode plate of the high-temperature electrolysis cell are respectively engraved with cathode flow channels and anode flow channels for gas and liquid circulation, and cathode flow channel inlets and cathode flow channels are located on the cathode plate. There are anode flow channel inlet and anode flow channel outlet on the anode plate, and there is a power interface on each side plate; the cathode plate and the anode plate are separated by ordinary gaskets, and the space between the ordinary gasket and the cathode plate is An additional catholyte chamber gasket can be added to store the catholyte layer; the catholyte chamber gasket is provided with an electrolyte inlet and an electrolyte outlet; the cathode plate, the anode plate, the common gasket and the catholyte chamber Gaskets are connected and fixed by high-temperature compression screws; heating systems are provided on the cathode plate and anode plate, and an electrolytic cell incubator is provided outside the electrolytic cell; between the cathode plate, the anode plate, the common gasket and the catholyte chamber gasket A closed space is formed, and the closed space is provided with a catalyst layer, a gas diffusion layer, an electrolyte and an electrolyte layer, and the order of arrangement is from the cathode plate to the anode plate, the cathode gas diffusion layer, the cathode catalyst layer, the cathode electrolyte layer, the solid state Electrolyte layer, anode catalyst layer, anode gas diffusion layer.

As a new type of high-temperature electrochemical urea electrolytic cell, the cathode plate and anode plate of the electrolytic cell are round, square or diamond.

As a new type of high temperature electrochemical urea electrolysis cell, the cathode plate, cathode flow channel, anode plate, anode flow channel, heating system, high temperature compression screw, cathode flow channel inlet, cathode flow channel outlet, anode flow channel The material of the channel inlet, anode flow channel outlet and power interface is one or more of graphite, stainless steel and engineering plastics.

As a new type of high-temperature electrochemical urea electrolytic cell, the electrolytic cell incubator is used to ensure the reaction temperature in the electrolytic cell, and its material is one or more of inorganic thermal insulation materials and organic thermal insulation materials.

As a new type of high-temperature electrochemical urea electrolytic cell, common gaskets and catholyte chamber gaskets are used to seal the electrolytic cell and avoid short circuits of bipolar plates. In addition, the catholyte chamber gasket is used to construct a catholyte chamber; the gasket material is one or more of silica gel, polytetrafluoroethylene, and engineering plastics.

As a new type of high-temperature electrochemical urea electrolytic cell, the cathode gas diffusion layer and the anode gas diffusion layer are made of one or more of carbon paper, carbon cloth, porous metal and alloy, porous metal compound, and porous stainless steel. .

As a new type of high-temperature electrochemical urea electrolytic cell, the cathode catalyst layer and the anode catalyst layer are made of one or more of non-metals, non-precious metals and precious metals.

As a new type of high-temperature electrochemical urea electrolysis cell, a closed space is formed between the cathode plate, the anode plate, the common gasket and the cathode electrolyte chamber gasket, and the closed space is provided with a catalyst layer, a gas diffusion layer, an electrolyte and Electrolyte layer, the sum of the thickness of each layer is consistent with the thickness of the enclosed space.

As a new type of high-temperature electrochemical urea electrolysis cell, the cathode flow channel inlet and cathode flow channel outlet are located outside the cathode plate, the anode flow channel inlet and anode flow channel outlet are located outside the anode plate, and the electrolyte inlet, electrolysis solution The liquid outlet is located on the outside of the catholyte chamber gasket, and the positions of the inlet and outlet can be interchanged according to the actual reaction requirements.

As a new type of high-temperature electrochemical urea electrolysis cell, the anode reactant is water vapor, which enters the anode flow channel from the anode flow channel inlet, and reaches the surface of the anode catalyst layer after being dispersed by the anode gas diffusion layer, and is oxidized into oxygen. The outlet of the flow channel flows out, and the protons generated at the same time pass through the solid electrolyte layer and the catholyte layer, and reach the surface of the cathode catalyst layer.

As a new type of high-temperature electrochemical urea electrolysis cell, the cathode reactants are carbon dioxide and nitrogen, which enter the cathode flow channel from the inlet of the cathode flow channel, and then reach the surface of the cathode catalyst layer after being dispersed by the cathode gas diffusion layer. , urea is generated by coupling on the surface of the cathode catalyst layer, and flows out from the outlet of the cathode flow channel.

As a new type of high-temperature electrochemical urea electrolytic cell, the catholyte layer has the functions of ion exchange and enhanced cathode reaction selectivity, and is made of one or more of ionic liquid, organic solvent, organic polymer, and inorganic salt composite More than two types, the catholyte layer has a certain fluidity, or is in the form of a sheet without fluidity, and its thickness is consistent with the catholyte chamber gasket, and the catholyte layer can be used or removed according to actual reaction requirements.

As a new type of high-temperature electrochemical urea electrolytic cell, the solid electrolyte layer has an ion exchange function, and its material is one of organic polymers, silicon oxides, phosphorus oxides, boron oxides, metals and alloys, and metal compounds. Or two or more kinds, and the solid electrolyte layer is in the form of a sheet.

As a new type of high-temperature electrochemical urea electrolysis cell, the anode flow channel is one or more of annular, serpentine, parallel, cross, and zigzag shapes, and the anode gas diffusion layer and the anode catalyst layer are sheet-shaped. .

As a new type of high-temperature electrochemical urea electrolytic cell, the cathode flow channel is one or more of annular, serpentine, parallel, cross, and zigzag shapes, and the cathode gas diffusion layer and the cathode catalyst layer are in the form of sheets. .

The device has the advantages of simple assembly process, easy size control, low material cost, remarkable reaction strengthening effect, and good application prospect in industrial production.

Description of drawings

FIG. 1 is a schematic structural diagram of a high-temperature electrochemical urea electrolytic cell device according to an embodiment.

In the figure: cathode plate 1, cathode flow channel 2, anode plate 3, anode flow channel 4, cathode gas diffusion layer 5, cathode catalyst layer 6, common gasket 7, catholyte liquid chamber gasket 8, catholyte liquid layer 9 , solid electrolyte layer 10, anode catalyst layer 11, anode gas diffusion layer 12, heating system 13, high temperature compression screw 14, electrolytic cell incubator 15, cathode flow channel inlet 16, cathode flow channel outlet 17, anode flow channel inlet 18 , Anode flow channel outlet 19 , power interface 20 , electrolyte inlet 21 , electrolyte outlet 22 .

2 is a schematic structural diagram of the main body block of the high-temperature electrochemical urea electrolytic cell device of the embodiment, which does not include a gas diffusion layer, a catalyst layer, an electrolyte layer, a solid electrolyte layer, and an electrolytic cell incubator.

FIG. 3 is a schematic structural diagram of the cathode plate 1 and the cathode flow channel 2 of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

FIG. 4 is a schematic structural diagram of the anode plate 3 and the anode flow channel 4 of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

FIG. 5 is a schematic structural diagram of the high-temperature compression screw 14 of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

FIG. 6 is a schematic structural diagram of the common gasket 7 of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

FIG. 7 is a schematic structural diagram of the gasket 8 of the catholyte chamber of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

8 is a schematic structural diagram of a gas diffusion layer, a catalyst layer, an electrolyte layer, and an electrolyte layer of a high-temperature electrochemical urea electrolytic cell device according to an embodiment.

In the figure: cathode gas diffusion layer 5 , cathode catalyst layer 6 , catholyte layer 9 , solid electrolyte layer 10 , anode catalyst layer 11 , anode gas diffusion layer 12 .

FIG. 9 is a schematic structural diagram of the electrolytic cell incubator 15 of the high-temperature electrochemical urea electrolytic cell device according to the embodiment.

Detailed ways

The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping the understanding of the present invention, and should not be regarded as a specific limitation of the present invention. Various modifications and variations can be made without departing from the scope of the invention as defined by the appended claims, and if any such modifications and variations exist, they will fall within the scope of the invention described herein Inside. In addition, the background art is intended to illustrate the research and development status and significance of the present invention, and is not intended to limit the application field of the present invention or the present application.

Example

A novel high-temperature urea-producing electrolytic cell device provided by the embodiment of the present utility model, the schematic diagram of the core unit structure is shown in FIG. 1 and FIG. , anode plate 3, anode flow channel 4, cathode gas diffusion layer 5, cathode catalyst layer 6, common gasket 7, catholyte chamber gasket 8, catholyte layer 9, solid electrolyte layer 10, anode catalyst layer 11, Anode gas diffusion layer 12, heating system 13, compression screw 14, electrolytic cell incubator 15, cathode flow channel inlet 16, cathode flow channel outlet 17, anode flow channel inlet 18, anode flow channel outlet 19, power interface 20, electrolysis Liquid inlet 21 and electrolyte outlet 22 .

In the embodiment of the present invention, the cathode plate 1 and the anode plate 3 of the electrolytic cell are circular, the anode flow channel 4 and the cathode flow channel 2 are annular, wherein the schematic diagram of the structure of the cathode plate 1 and the cathode flow channel 2 is shown in FIG. The schematic diagram of the structure of the plate 3 and the anode flow channel 4 is shown in FIG. 4 .

In the embodiment of the present invention, the cathode plate 1, cathode flow channel 2, anode plate 3, anode flow channel 4, heating system 13, cathode flow channel inlet 16, cathode flow channel outlet 17, anode flow channel inlet 18, The material of the anode flow channel outlet 19 and the power interface 20 is stainless steel, the material of the pressing screw 14 is engineering plastic, and the schematic diagram of the structure of the pressing screw is shown in FIG. 5 .

In the embodiment of the present utility model, the common gasket 7 and the catholyte chamber gasket 8 are used to seal the electrolytic cell and avoid the short circuit of the bipolar plates. In addition, the catholyte chamber gasket 8 is used to construct a catholyte chamber; The sheet material is expanded polytetrafluoroethylene, the schematic diagram of the structure of the common gasket 7 is shown in FIG. 6 , and the schematic diagram of the structure of the gasket 8 of the catholyte chamber is shown in FIG. 7 .

In the embodiment of the present invention, the cathode gas diffusion layer 5 is made of porous titanium, and the anode gas diffusion layer 12 is made of stainless steel mesh.

In the embodiment of the present invention, the cathode catalyst layer 6 is made of metal alloy, and the anode catalyst layer 11 is made of precious metal.

In the embodiment of the present utility model, a closed space is formed between the cathode plate 1, the anode plate 3, the common gasket 7 and the cathode electrolyte chamber gasket 8, and the closed space is provided with a cathode gas diffusion layer 5, a cathode catalyst layer 6, The catholyte layer 9, the solid electrolyte layer 10, the anode catalyst layer 11, and the anode gas diffusion layer 12, the thickness and structure of each layer are shown in FIG. 8 .

In the embodiment of the present invention, the anode reactant is water vapor, which enters the anode flow channel 4 through the anode flow channel inlet 18, is dispersed by the anode gas diffusion layer 12 and reaches the surface of the anode catalyst layer 11, where it is oxidized into oxygen gas, and is transported from the anode flow channel by the anode flow channel. The outlet 19 flows out, and the protons generated at the same time pass through the solid electrolyte layer 10 and the catholyte layer 9 to reach the surface of the cathode catalyst layer 6 .

In the embodiment of the present utility model, the cathode reactants are carbon dioxide and nitrogen, which enter the cathode flow channel 2 through the cathode flow channel inlet 16, and then reach the surface of the cathode catalyst layer 6 after being dispersed by the cathode gas diffusion layer 5. The surface of the cathode catalyst layer 6 is coupled to generate urea, which flows out from the cathode flow channel outlet 17 .

In the embodiment of the present invention, the catholyte layer 9 has functions such as ion exchange and enhancement of the cathode reaction selectivity, and the material is ionic liquid. The catholyte layer 9 has a certain fluidity, and its thickness is the same as that of the catholyte chamber gasket 8 .

In the embodiment of the present invention, the solid electrolyte layer 10 has an ion exchange function, and the material is a composite of silicon oxide, metal phosphate, and metal alloy, and the solid electrolyte layer 10 is in the shape of a sheet.

In the embodiment of the present utility model, the electrolytic cell insulation box 15 is used to ensure the reaction temperature in the electrolytic cell, and its material is thermal insulation cotton, and its structural schematic diagram is shown in FIG. 9 .

Claims (8)

1. a novel high temperature electrochemical urea electrolytic cell device is characterized in that: comprise cathode plate (1), cathode flow channel (2), anode plate (3), anode flow channel (4), cathode gas diffusion layer ( 5), cathode catalyst layer (6), common gasket (7), catholyte chamber gasket (8), catholyte layer (9), solid electrolyte layer (10), anode catalyst layer (11), anode a gas diffusion layer (12), a heating system (13), a high temperature compression screw (14), an electrolytic cell incubator (15), The cathode plate (1) and the anode plate (3) of the high-temperature electrolytic cell are respectively engraved with a cathode flow channel (2) and an anode flow channel (4) for supplying gas and liquid, and the cathode plate (1) has a cathode flow channel inlet ( 16) and the cathode flow channel outlet (17), the anode plate (3) is provided with an anode flow channel inlet (18) and an anode flow channel outlet (19), and each side plate is provided with a power interface (20); The plate (1) and the anode plate (3) are separated by an ordinary gasket (7). An additional catholyte chamber gasket (8) can be added between the ordinary gasket (7) and the cathode plate (1). For storing catholyte layer (9); catholyte chamber gasket (8) is provided with electrolyte inlet (21) and electrolyte outlet (22); cathode plate (1), anode plate (3), common pad The sheet (7) and the catholyte chamber gasket (8) are connected and fixed by high temperature pressing screws (14); a heating system (13) is provided on the cathode plate (1) and the anode plate (3), There is an electrolytic cell incubator (15); a closed space is formed between the cathode plate (1), the anode plate (3), the common gasket (7) and the cathode electrolyte chamber gasket (8), and the closed space is provided with a catalyst layer, gas diffusion layer, electrolyte and electrolyte layer, the order of arrangement is from cathode plate (1) to anode plate (3), cathode gas diffusion layer (5), cathode catalyst layer (6), catholyte layer ( 9), a solid electrolyte layer (10), an anode catalyst layer (11), and an anode gas diffusion layer (12). 2. A novel high-temperature electrochemical urea electrolytic cell device according to claim 1, characterized in that: the cathode plate (1) and the anode plate (3) are circular, square or rhombus. 3. a kind of novel high temperature electrochemical urea electrolytic cell device according to claim 1 is characterized in that: described cathode plate (1), anode plate (3), common gasket (7) and catholyte chamber A closed space is formed between the gaskets (8), the closed space is provided with a catalyst layer, a gas diffusion layer, an electrolyte and an electrolyte layer, and the total thickness of each layer is consistent with the thickness of the closed space. 4. A novel high-temperature electrochemical urea electrolytic cell device according to claim 1, characterized in that: the cathode flow channel inlet (16) and the cathode flow channel outlet (17) are arranged on the outside of the cathode plate (1) , the anode flow channel inlet (18) and the anode flow channel outlet (19) are arranged on the outside of the anode plate (3), and the electrolyte inlet (21) and the electrolyte outlet (22) are arranged on the outside of the catholyte chamber gasket (8). , the inlet and outlet positions can be interchanged according to the actual response needs. 5. a kind of novel high temperature electrochemical urea electrolytic cell device according to claim 1, is characterized in that: described catholyte layer (9) has ion exchange, strengthens the cathode reaction selectivity function, catholyte layer (9) 9) It has a certain fluidity or is in the form of a sheet without fluidity, and its thickness is the same as that of the catholyte chamber gasket (8). 6. A novel high-temperature electrochemical urea electrolytic cell device according to claim 1, characterized in that: the solid electrolyte layer (10) has an ion exchange function, and the solid electrolyte layer (10) is in a sheet shape. 7. a kind of novel high-temperature electrochemical urea electrolytic cell device according to claim 1, is characterized in that: described anode flow channel (4) is a ring shape, serpentine shape, parallel shape, cross shape, and broken line shape. One or more kinds, the anode gas diffusion layer (12) and the anode catalyst layer (11) are in sheet shape. 8. a kind of novel high temperature electrochemical urea electrolytic cell device according to claim 1, is characterized in that: described cathode flow channel (2) is a ring shape, serpentine shape, parallel shape, cross shape, and broken line shape. One or two or more kinds, the cathode gas diffusion layer (5) and the cathode catalyst layer (6) are in sheet shape.

Images