Diffusion layer used in hydrogen production electrolyzer and its preparation process

Abstract

The present invention discloses a diffusion layer used in a hydrogen production electrolyzer and a preparation process thereof. The technical scheme thereof is as follows: the diffusion layer used in the hydrogen production electrolyzer comprises a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer, and the porosity of the non-woven fabric base layer is 78%-82%. The diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process.

Description

Technical Field

[0001] The present invention relates to the field of hydrogen production electrolysis, and in particular to a diffusion layer used in a hydrogen production electrolyzer and a preparation process thereof. Background Art

[0002] A hydrogen electrolyzer is a device that produces hydrogen and oxygen by electrolyzing water. In this process, electrical energy is provided to split water molecules into hydrogen and oxygen. The process is usually carried out in a specially designed electrolyzer and involves the transfer of electrons from water molecules between an anode (positive electrode) and a cathode (negative electrode). There are two main types of hydrogen electrolyzers: alkaline electrolyzers and solid-state electrolyzers. Alkaline electrolyzers usually contain alkaline electrolytes and mineral acid salts, such as potassium hydroxide and sodium hydroxide, to increase the efficiency of electrolysis. In this electrolyzer, water molecules are decomposed into oxygen and negative ions at the anode, and the negative ions then migrate through the electrolyte to the cathode, where they combine to produce hydrogen. The main advantages of alkaline electrolyzers are low cost and simple operation. However, they are relatively inefficient and may fail at higher temperatures.

[0003] Hydrogen electrolyzers are widely used in hydrogen production, energy storage and fuel cells. By using renewable energy (such as solar, wind or hydroelectric power) as a power source, hydrogen electrolyzers can provide a more sustainable and environmentally friendly way to produce hydrogen.

[0004] In the structure of the hydrogen production electrolyzer, there is a diffusion layer, the main function of which is to increase the reaction area, etc. The current diffusion layer has a relatively complex production process and needs to be improved. Summary of the invention

[0005] The object of the present invention is to provide a diffusion layer used in a hydrogen production electrolyzer and a preparation process thereof, so as to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: the diffusion layer used in the hydrogen production electrolyzer includes a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer, and the porosity of the non-woven fabric base layer is 78%-82%.

[0007] Preferably, the non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer comprises the following components by mass: 50-80 parts of chlorinated polypropylene, 4-10 parts of cellulose derivatives, 8-15 parts of epoxy resin, 4-10 parts of polyamide resin, 3-8 parts of water-soluble melamine resin, and 2-5 parts of organic peptide compounds.

[0008] The present invention also discloses a preparation process of a diffusion layer used in a hydrogen production electrolyzer, comprising the following steps:

[0009] S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber;

[0010] S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 30%-40%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing;

[0011] S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine;

[0012] S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated;

[0013] S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing;

[0014] S6, shaping: Use high temperature to iron the fiber cotton into a hot rod;

[0015] S7, knife cutting into rolls: The knife structure is designed to remove impurities on the mesh surface, and then receive the needle-punched non-woven fabric formed by the hot rod and roll it into a roll.

[0016] Preferably, in S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and the puncture is repeated.

[0017] Preferably, during shaping, the S6 utilizes high temperature to roll-form the fiber cotton, and the temperature of the roll is 80-85°C.

[0018] Preferably, when S2 is loosening and mixing the cotton, the raw fibers are placed in a mixing box for loosening and mixing. The mixing box is a pressure box, and air is blown in the pressure box to comb the fibers in the transverse direction to ensure uniform transverse distribution of the fibers.

[0019] Preferably, after the S5 web laying and spunlacing, a rinsing operation is performed, the spunlaced nonwoven fabric is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

[0020] Preferably, the rinsing liquid in the rinsing box includes the following components by mass: 4-8 parts of a surfactant, 10-20 parts of citric acid, 1-3 parts of a preservative and 300-400 parts of softened water, wherein the preservative is one or more of sorbic acid and its salts, dehydroacetic acid and its sodium salts, parabens, and sodium diacetate, and the surfactant is one of a non-ionic surfactant, an amphoteric surfactant, and a compound surfactant.

[0021] Preferably, the cutting knife structure includes a frame, on which a first blade, a second blade and a third blade are arranged in parallel to slide vertically, and a first hydraulic cylinder, a second hydraulic cylinder and a third hydraulic cylinder are installed on the frame to respectively drive the first blade, the second blade and the third blade to slide, a coating box is fixed on the frame, a PCT heater is embedded in the third blade, and a scraping structure is provided on the second blade for pushing the protective layer in the coating box from the coating box to the surface of the third blade when the second blade moves upward; the scraping structure includes a push plate, a push rod, a fixed rod, a slide groove, a slider, a ball hinge seat and a swing rod, the push plate is slidably connected in the coating box, the push rod is fixed at the bottom of the push plate and is slidably connected between the coating box, the fixed rod is fixed at the end of the push rod, the slide groove is opened in the fixed rod, the slider is slidably connected in the slide groove, one end of the swing rod is hinged to the second blade, and the other end of the swing rod is connected to the slider through a ball hinge seat.

[0022] By adopting the above technical solution, the diffusion layer can be cut by using the cutter structure, which solves a technical problem: the technical problem is that the traditional cutter adopts a one-time overall cutting method, while the diffusion layer has a three-layer structure. Single one-time overall cutting will cause burrs to protrude. The cutter structure used in this process can solve this problem; when the cutter structure is applied, the first hydraulic cylinder on the frame can be started to drive the first blade to cut the top protective layer in the diffusion layer, but the non-woven fabric base layer is not cut; then the second hydraulic cylinder is started to drive the second blade to cut the non-woven fabric base layer; finally, the third hydraulic cylinder is started to drive the third blade to cut the bottom the protective layer is cut off; when the second hydraulic cylinder drives the second blade downward, it will drive the swing rod to swing, and the push rod on the fixed rod can be driven upward through the cooperation of the ball joint seat, the slider, the slide groove, etc., thereby driving the push plate to slide in the coating box, so that the solidified coating in the coating box can leak out from the opening, so that the solidified solid coating can be cut off when the third hydraulic cylinder drives the third blade downward. Since a PCT heater is embedded in the third blade, it can melt the solid coating on the surface of the third blade, and while cutting off the bottom protective layer, the end face of the entire diffusion layer is repaired, thereby forming an end face with smaller burrs.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a flowchart of the present invention;

[0026] Figure 2 It is one of the structural schematic diagrams of the cutter structure in the present invention;

[0027] Figure 3 is a structural cross-sectional view of the cutter structure of the present invention;

[0028] Figure 4 for Figure 3 A in the enlarged view;

[0029] Figure 5 This is the second structural schematic diagram of the cutter structure in the present invention;

[0030] Figure 6 for Figure 5 Enlarged view of point B in .

[0031] Among them, 1. frame; 2. first blade; 3. second blade; 4. third blade; 5. first hydraulic cylinder; 6. second hydraulic cylinder; 7. third hydraulic cylinder; 8. coating box; 9. push plate; 10. push rod; 11. fixed rod; 12. slide groove; 13. slider; 14. ball joint seat; 15. swing rod. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Example 1

[0034] See also Figure 1-Figure 6 This embodiment provides a technical solution: a diffusion layer used in a hydrogen production electrolyzer includes a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer. The porosity of the non-woven fabric base layer is 78%.

[0035] The non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer includes the following components by mass: 60 parts of chlorinated polypropylene, 7 parts of cellulose derivatives, 12 parts of epoxy resin, 7 parts of polyamide resin, 6 parts of water-soluble melamine resin, and 3 parts of organic peptide compounds.

[0036] This embodiment also discloses a preparation process of a diffusion layer used in a hydrogen production electrolyzer, comprising the following steps:

[0037] S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber;

[0038] S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 31%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing;

[0039] S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine;

[0040] S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated;

[0041] S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing;

[0042] S6, shaping: Use high temperature to iron the fiber cotton into a hot rod;

[0043] S7, knife cutting into rolls: The knife structure is designed to remove impurities on the mesh surface, and then receive the needle-punched non-woven fabric formed by the hot rod and roll it into a roll.

[0044] Among them, in S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated.

[0045] Wherein, during shaping, the S6 utilizes high temperature to roll the fiber cotton into shape, and the temperature of the rolling rod is 80°C.

[0046] Among them, when S2 is loosening and mixing cotton, the raw fiber is put into a mixing box for loosening and mixing. The mixing box is an air pressure box. Air flow is blown in the air pressure box to comb the fibers in the horizontal direction to ensure the uniformity of the horizontal distribution of the fibers.

[0047] Among them, after the S5 web laying and spunlacing, a rinsing operation is performed, the non-woven fabric after spunlacing is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

[0048] The rinse box includes the following components by mass: 4 parts of surfactant, 20 parts of citric acid, 3 parts of preservative and 300 parts of softened water, wherein the preservative is sorbic acid and its salts, and the surfactant is a non-ionic surfactant.

[0049] Among them, the diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process.

[0050] refer to Figures 1 to 6, wherein the cutter structure includes a frame 1, on which a first blade 2, a second blade 3 and a third blade 4 are arranged in parallel for vertical sliding, a first hydraulic cylinder 5, a second hydraulic cylinder 6 and a third hydraulic cylinder 7 are installed on the frame 1 to respectively drive the first blade 2, the second blade 3 and the third blade 4 to slide, a coating box 8 is fixed on the frame 1, a PCT heater is embedded in the third blade 4, and a scraping structure is provided on the second blade 3 to push the protective layer in the coating box 8 from the coating box 8 to the surface of the third blade 4 when the second blade 3 moves upward The scraping structure includes a push plate 9, a push rod 10, a fixed rod 11, a slide groove 12, a slider 13, a ball hinge seat 14 and a swing rod 15. The push plate 9 is slidably connected in the coating box 8. The push rod 10 is fixed at the bottom of the push plate 9 and is slidably connected to the coating box 8. The fixed rod 11 is fixed at the end of the push rod 10. The slide groove 12 is opened in the fixed rod 11. The slider 13 is slidably connected in the slide groove 12. One end of the swing rod 15 is hinged to the second blade 3, and the other end of the swing rod 15 is connected to the slider 13 through the ball hinge seat 14.

[0051] refer to Figures 1 to 6 The diffusion layer can be cut by using a cutter structure, which solves a technical problem: the technical problem is that the traditional cutter adopts a one-time overall cutting method, while the diffusion layer has a three-layer structure. Single one-time overall cutting will cause burrs to protrude. The cutter structure used in this process can solve this problem; when the cutter structure is applied, the first hydraulic cylinder 5 on the frame 1 can be started to drive the first blade 2 to cut the top protective layer in the diffusion layer, but the non-woven fabric base layer is not cut; then the second hydraulic cylinder 6 is started to drive the second blade 3 to cut the non-woven fabric base layer; finally, the third hydraulic cylinder 7 is started to drive the third blade 4 to cut the bottom protective layer; in the second hydraulic cylinder 7, the first hydraulic cylinder 5 is started to drive the first blade 2 to cut the top protective layer in the diffusion layer, but the non-woven fabric base layer is not cut; then, the second hydraulic cylinder 6 is started to drive the second blade 3 to cut the non-woven fabric base layer; finally, the third hydraulic cylinder 7 is started to drive the third blade 4 to cut the bottom protective layer; When the pressure cylinder 6 drives the second blade 3 downward, it will drive the swing rod 15 to swing, and through the cooperation of the ball hinge seat 14, the slider 13, the slide groove 12, etc., it can drive the push rod 10 on the fixed rod 11 to move upward, thereby driving the push plate 9 to slide in the coating box 8, so that the solidified coating in the coating box 8 can leak out from the opening, so that the solidified solid coating can be cut off when the third hydraulic cylinder 7 drives the third blade 4 downward. Since a PCT heater is embedded in the third blade 4, it can melt the solid coating on the surface of the third blade 4, and while cutting off the bottom protective layer, the end face of the entire diffusion layer is repaired, thereby forming an end face with smaller burrs.

[0052] Example 2

[0053] See also Figure 1-Figure 6 This embodiment provides a technical solution: a diffusion layer used in a hydrogen production electrolyzer includes a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer. The porosity of the non-woven fabric base layer is 82%.

[0054] The non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer includes the following components by mass: 70 parts of chlorinated polypropylene, 8 parts of cellulose derivatives, 15 parts of epoxy resin, 10 parts of polyamide resin, 3 parts of water-soluble melamine resin, and 2 parts of organic peptide compounds.

[0055] This embodiment also discloses a preparation process of a diffusion layer used in a hydrogen production electrolyzer, comprising the following steps:

[0056] S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber;

[0057] S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 38%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing;

[0058] S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine;

[0059] S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated;

[0060] S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing;

[0061] S6, shaping: Use high temperature to iron the fiber cotton into a hot rod;

[0062] S7, knife cutting into rolls: The knife structure is designed to remove impurities on the mesh surface, and then receive the needle-punched non-woven fabric formed by the hot rod and roll it into a roll.

[0063] Among them, in S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated.

[0064] Wherein, during shaping, the S6 utilizes high temperature to roll-form the fiber cotton, and the temperature of the roll is 85°C.

[0065] Among them, when S2 is loosening and mixing cotton, the raw fiber is put into a mixing box for loosening and mixing. The mixing box is an air pressure box. Air flow is blown in the air pressure box to comb the fibers in the horizontal direction to ensure the uniformity of the horizontal distribution of the fibers.

[0066] Among them, after the S5 web laying and spunlacing, a rinsing operation is performed, the non-woven fabric after spunlacing is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

[0067] The rinse box includes the following components by mass: 4 parts of surfactant, 20 parts of citric acid, 3 parts of preservative and 400 parts of softened water, wherein the preservative is dehydroacetic acid and sodium salt.

[0068] Among them, the diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process.

[0069] Example 3

[0070] See also Figure 1-Figure 6 This embodiment provides a technical solution: a diffusion layer used in a hydrogen production electrolyzer includes a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer. The porosity of the non-woven fabric base layer is 81%.

[0071] The non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer includes the following components by mass: 60 parts of chlorinated polypropylene, 8 parts of cellulose derivatives, 8 parts of epoxy resin, 10 parts of polyamide resin, 8 parts of water-soluble melamine resin, and 5 parts of organic peptide compounds.

[0072] This embodiment also discloses a preparation process of a diffusion layer used in a hydrogen production electrolyzer, comprising the following steps:

[0073] S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber;

[0074] S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 34%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing;

[0075] S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine;

[0076] S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated;

[0077] S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing;

[0078] S6, shaping: Use high temperature to iron the fiber cotton into a hot rod;

[0079] S7, knife cutting into rolls: The knife structure is designed to remove impurities on the mesh surface, and then receive the needle-punched non-woven fabric formed by the hot rod and roll it into a roll.

[0080] Among them, in S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated.

[0081] Wherein, during shaping, the S6 utilizes high temperature to roll-form the fiber cotton, and the temperature of the rolling rod is 82°C.

[0082] Among them, when S2 is loosening and mixing cotton, the raw fiber is put into a mixing box for loosening and mixing. The mixing box is an air pressure box. Air flow is blown in the air pressure box to comb the fibers in the horizontal direction to ensure the uniformity of the horizontal distribution of the fibers.

[0083] Among them, after the S5 web laying and spunlacing, a rinsing operation is performed, the non-woven fabric after spunlacing is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

[0084] The rinse box includes the following components by mass: 5 parts of surfactant, 13 parts of citric acid, 2 parts of preservative and 300 parts of softened water, wherein the preservative is a paraben and the surfactant is a compound surfactant.

[0085] Among them, the diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process.

[0086] Example 4

[0087] See also Figure 1This embodiment provides a technical solution: a diffusion layer used in a hydrogen production electrolyzer includes a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer. The porosity of the non-woven fabric base layer is 82%.

[0088] The non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer includes the following components by mass: 50 parts of chlorinated polypropylene, 10 parts of cellulose derivatives, 8 parts of epoxy resin, 10 parts of polyamide resin, 3 parts of water-soluble melamine resin, and 2 parts of organic peptide compounds.

[0089] This embodiment also discloses a preparation process of a diffusion layer used in a hydrogen production electrolyzer, comprising the following steps:

[0090] S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber;

[0091] S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 35%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing;

[0092] S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine;

[0093] S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated;

[0094] S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing;

[0095] S6, shaping: Use high temperature to iron the fiber cotton into a hot rod;

[0096] S7, knife cutting into rolls: The knife structure is designed to remove impurities on the mesh surface, and then receive the needle-punched non-woven fabric formed by the hot rod and roll it into a roll.

[0097] Among them, in S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated.

[0098] Wherein, during shaping, the S6 utilizes high temperature to roll-form the fiber cotton, and the temperature of the rolling rod is 82°C.

[0099] Among them, when S2 is loosening and mixing cotton, the raw fiber is put into a mixing box for loosening and mixing. The mixing box is an air pressure box. Air flow is blown in the air pressure box to comb the fibers in the horizontal direction to ensure the uniformity of the horizontal distribution of the fibers.

[0100] Among them, after the S5 web laying and spunlacing, a rinsing operation is performed, the non-woven fabric after spunlacing is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

[0101] The rinse box includes the following components by mass: 5 parts of surfactant, 15 parts of citric acid, 2 parts of preservative and 400 parts of softened water, wherein the preservative is sodium diacetate and the surfactant is a non-ionic surfactant.

[0102] Among them, the diffusion layer used in the hydrogen production electrolyzer has the advantages of less surface fiber impurities and high fiber smoothness; the preparation process of the diffusion layer used in the hydrogen production electrolyzer has the advantage of simple production process.

[0103] In order to verify the superiority of the diffusion layer, the performance of common non-woven fabrics on the market and the non-woven fabrics of the four embodiments of the present invention were tested, and the following data were obtained:

[0104] cost Bursting strength tensile strength Compare files 100％ 100％ 100％ Example 1 78％ 123％ 145％ Example 2 64％ 132％ 128％ Example 3 71％ 122％ 144％ Example 4 77％ 129％ 131％

[0105] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A diffusion layer used in a hydrogen production electrolyzer, characterized in that: It comprises a non-woven fabric base layer, and protective layers are respectively arranged on both sides of the non-woven fabric base layer, and the porosity of the non-woven fabric base layer is 78%-82%; the non-woven fabric base layer is applied between several groups of plate electrodes and membrane electrodes, and the protective layer comprises the following components by weight: 50-80 parts of chlorinated polypropylene, 4-10 parts of cellulose derivatives, 8-15 parts of epoxy resin, 4-10 parts of polyamide resin, 3-8 parts of water-soluble melamine resin, and 2-5 parts of organic peptide compounds.

2. A process for preparing a diffusion layer used in a hydrogen production electrolyzer, characterized in that: The following steps are involved: S1. Feeding: using purified terephthalic acid or dimethyl terephthalate and ethylene glycol as raw materials to obtain a fiber-forming polymer polyethylene terephthalate through esterification or transesterification and polycondensation reaction, and then spinning and dyeing to obtain raw fiber; S2, opening and mixing: put the raw fiber into the mixing box for loosening and mixing. After the block fiber is opened and mixed in the mixing box, the single-sided state is controlled to reach 30%-40%, and then it is transported to the middle warehouse mixing box to make the cotton layer uniform by vibration mixing; S3, combing and spinning: comb the fibers that have been processed in the mixing box into single fibers, then form a mesh fiber layer, and then gather into fiber strips and transmit them to the web laying machine; S4. Net laying and needling: The net laying machine receives the fiber strips transmitted by the carding machine for net laying. The model progress of the net laying machine is automatically adjusted by the frequency conversion four-segment to reduce the phenomenon that the net is thick on both sides and thin in the middle. After the net is formed, it is transmitted to the needling machine, and the needling machine is used to pre-reinforce the fiber net to form a grey cloth. Then, the fiber net is reinforced again by using a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated; S5. Laying and spunlacing: feeding the needle-punched mesh into the spunlacing box for spunlacing; S6, shaping: Use high temperature to iron the fiber cotton into a hot rod; S7, cutting into rolls: a cutting structure is designed to remove impurities on the mesh surface, and then receive the needle-punched nonwoven fabric formed by the hot roller and roll it; the cutting structure comprises a frame (1), on which a first blade (2), a second blade (3) and a third blade (4) are arranged in parallel for vertical sliding; a first hydraulic cylinder (5), a second hydraulic cylinder (6) and a third hydraulic cylinder (7) are installed on the frame (1) for respectively driving the first blade (2), the second blade (3) and the third blade (4) to slide; a coating box (8) is fixed on the frame (1), a PCT heater is embedded in the third blade (4), and the second blade (3) is provided with a protective layer in the coating box (8) to be pushed out of the coating box (8) when the second blade (3) moves upward. ) enters into the scraping structure of the surface of the third blade (4); the scraping structure includes a push plate (9), a push rod (10), a fixed rod (11), a slide groove (12), a slider (13), a ball hinge seat (14) and a swing rod (15), the push plate (9) is slidably connected in the coating box (8), the push rod (10) is fixed at the bottom of the push plate (9) and is slidably connected to the coating box (8), the fixed rod (11) is fixed at the end of the push rod (10), the slide groove (12) is opened in the fixed rod (11), the slider (13) is slidably connected in the slide groove (12), one end of the swing rod (15) is hinged to the second blade (3), and the other end of the swing rod (15) is connected to the slider (13) through the ball hinge seat (14).

3. The process for preparing a diffusion layer used in a hydrogen production electrolyzer according to claim 2, characterized in that: In S4, after the fiber web is pre-reinforced by a needle punching machine to form a grey cloth, a sodium chloride solution with a mass concentration of 1% is sprayed on the fiber web, and then the fiber web is reinforced again by a triangular or other shaped cross-section with barbs on the edges, and puncture is repeated.

4. The process for preparing a diffusion layer used in a hydrogen production electrolyzer according to claim 2, characterized in that: When the S6 is being shaped, the fiber cotton is shaped by a hot roller at high temperature, and the temperature of the hot roller is 80-85°C.

5. The process for preparing a diffusion layer used in a hydrogen production electrolyzer according to claim 2, characterized in that: When S2 is loosening and mixing cotton, the raw fibers are placed in a mixing box for loosening and mixing. The mixing box is an air pressure box, and air is blown in the air pressure box to comb the fibers in the transverse direction to ensure uniform transverse distribution of the fibers.

6. The process for preparing a diffusion layer used in a hydrogen production electrolyzer according to claim 2, characterized in that: After the S5 web laying and spunlacing, a rinsing operation is performed, the spunlaced nonwoven fabric is squeezed with water by a padder, and then pulled into a rinsing box by a traction machine for rinsing, and then washed once, and then transferred to an air dryer for air drying.

7. The process for preparing a diffusion layer used in a hydrogen production electrolyzer according to claim 2, characterized in that: The rinsing liquid in the rinsing box includes the following components by mass: 4-8 parts of surfactant, 10-20 parts of citric acid, 1-3 parts of preservative and 300-400 parts of softened water, the preservative is one or more of sorbic acid and its salts, dehydroacetic acid and sodium salts, parabens, sodium diacetate, and the surfactant is one of a non-ionic surfactant, an amphoteric surfactant, and a compound surfactant.

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