WO1998040535A1

WO1998040535A1 - Electrolytic ozone-generating apparatus and the process for manufacturing the same

Info

Publication number: WO1998040535A1
Application number: PCT/CN1998/000030
Authority: WO
Inventors: Song Hu; Yuanquan Zhou; Rong Gao
Original assignee: Wuhan University
Priority date: 1997-03-07
Filing date: 1998-03-04
Publication date: 1998-09-17
Also published as: WO1998040535A8; CN1195643A; JP3025473B2; CN1128759C; TW401373B; AU6288498A; JPH111789A

Abstract

The present invention relates to an electrolytic ozone-generating apparatus and the process for manufacturing the same. The apparatus comprises an ozonizer, an anode water box, a cathode water box, an equilibrium device, and circulating tubes between water boxes and the ozonizer, and is characterized in that said ozonizer comprises (a) a cation-exchange membrane, (b) an anodic catalyst sheet (comprising mainly of PbO2), (c) a cathodic catalyst sheet (comprising mainly of Pt-C powder), (d) a porous anode current-collecting plaque, and (e) a cathode current-collecting plaque. Whereby said anodic and cathodic catalyst sheets contact closely with the corresponding side of the membrane, and said anode and cathode current-collecting plaques are in contact with the corresponding side of the anodic and cathodic catalyst sheets. This apparatus can be produced in mass-scale with low cost, and operated stable with high ozone generation efficiency under pressure.

Description

Electrolytic ozone generating device and preparation method thereof

FIELD OF THE INVENTION The present invention relates to an electrolytic ozone generator, which belongs to the fields of electrochemical technology and ozone application technology. BACKGROUND OF THE INVENTION The advantages of sterilization by ozone method are receiving increasing attention. At present, corona discharge methods using high frequency and high voltage are mostly used to generate ozone, and research and development of electrochemical methods to generate high concentration ozone have attracted widespread attention. The basic principle of electrochemical production of ozone is well known: ozone generation takes deionized water as the raw material. When a DC power supply is applied, the electrochemical reaction formula of the cathode and anode is:

Cathode hydrogen evolution reaction formula: 2H ÷ + 2e-* H ₂ † (1)

Cathodic oxygen depolarization reaction: l / 20 ₂ + 2H ++ 2e- → H ₂ 0 (2)

Anode main reaction formula: H ₂ 0— 1/30 ₃ † + 2e- + 2H + (3)

Anode reaction equation: H ₂ 0- * l / 20 ₂ f + 2e- + 2H ^÷ (4)

The protons produced by the anode reaction migrate to the cathode through the cation exchange membrane in the form of water-solvated protons under the action of a direct-current electric field.

According to the above electrochemical reaction principle, it is known that the core part constituting a most basic electrolytic ozone generating device is an electrolytic cell. The electrolytic cell must have an anode, a cathode, an electrolyte, and raw water.

Chinese patent application CN 8 6 1 0 8 7 9 2 A describes a solid polymer electrolyte structure, which includes a membrane, a plurality of conductive particles and a conductive water-permeable substrate member, wherein the conductive particles and the conductive water-permeable substrate ( As a current collector plate) they are physically or electrically contacted with each other and embedded in the diaphragm, or combined with the diaphragm. Among these membranes, fluorocarbon materials are generally preferred. To make conductive water-permeable base The body is embedded in the fluorocarbon film, and the fluorocarbon is preferably in a thermoplastic state. The conductive water-permeable substrate includes carbon cloth, carbon paper, metal mesh, metal felt, and porous metal sheet. Carbon cloth is preferred. Electrocatalytically active particles can be added to the surface of the diaphragm using a variety of techniques, including pressurization, mixing with solvents, and blending with powder of the diaphragm or other polymer. One specific method is as follows: First, prepare a thin film composed of electro-catalytically active particles by using a binder such as polytetrafluoroethylene or a membrane in a thermoplastic state. The composition is subject to being in a porous film state. This film can then be laminated between the collector and the diaphragm.

The film can be prepared from a thermoplastic ion exchange membrane mix containing 10% (by weight) carbon particles with a particle size of 30 microns and 5% platinum on it. The mixture can be hot-pressed at a temperature of 3 0 ° C and a pressure of 1 ton / inch ² (155 atmospheres) for 1.5 minutes to prepare a film having a thickness of less than 0.05 mm. The film can be laminated between the carbon cloth collector plate and the membrane by conventional hot pressing techniques. Afterwards, the carbon cloth can be embedded in the diaphragm, the method is as follows: preheat both the diaphragm / carbon cloth together for about 30 seconds at a temperature of 120 ° (:) and atmospheric pressure, and then at the same temperature and heating 225 seconds, the pressure in, and then in 2. 1 - - 2 tons / ⁱⁿ² (310 atm 155) - heated to about under pressure - (465 atm 310) 3 tons / ⁱⁿ² 60 seconds.

JP, Hei 4-8 8 1 8 2 proposed the use of a perfluorosulfonic acid cation exchange membrane (type 1 17) manufactured by DuPont of the United States, and the suspension (suspension) of a commercial ion powder (ion exchange resin powder) was coated on the surface. ) Liquid, a pressure of 5 kg / cm ² is applied, and the porous ion exchange resin layer is formed by heating at a temperature of 180 ° to 200 ° C for 30 minutes. The thickness of the surface layer of this ion exchange resin layer is 100 ° Microns. On the formed ion exchange resin layer, a porous layer was formed with lead oxide as an anode electrode. A ruthenium metal film is formed on the surface of the ion-exchange membrane opposite to this porous layer by electroless plating as a cathode.

The specific method for preparing a lead oxide anode is to first apply a coating solution containing 75% titanium and 25% platinum on a plate-like substrate made of sintered tantalum powder, and form a platinum / An intermediate layer made of tantalum. An 800 g / l lead nitrate aqueous solution was used as the electrolyte. After adding a small amount of nitric acid, the solution was heated to 70. The foregoing substrate and titanium were immersed in the electrolyte, and a current density of 10 A / dm ^{2 was} previously used. Pre-electrolysis, and then electrodeposition-dioxide on the surface of the aforementioned substrate with a current density of 4 A / dm ² The lead layer serves as the anode. The surface thickness of the lead dioxide layer is 100 m, and the electrodeposited lead dioxide layer anode is pressed against the ion exchange resin layer side of the ion exchange membrane at a pressure of 1.0 kg / cm ² to form an electrode structure. .

JP, Hei 2-4 3 3 8 9 and J P, Hei 2-4 3 3 9 0 have proposed a method for manufacturing an ion exchange resin film and a lead dioxide electrode connector. In this method, an aqueous solution containing lead ions is disposed on one side of a cation or anion exchange resin film, and an aqueous solution of hypochlorous acid (or an aqueous solution of bromine) is disposed on the other side, so that lead dioxide is precipitated on one surface of the ion exchange resin film. The coating serves as an anode catalyst for the production of ozone by electrolyzing water.

U S 4 9 2 7 8 0 0 introduces an electrode catalyst containing lead dioxide electrolytic deposition layer and a method for preparing the electrode catalyst. Particles containing β-lead dioxide powder are dispersed in the catalyst deposition layer. These particles contain β-lead dioxide powder and an optional electrolytic co-catalyst. The electrolytic co-catalyst is one of PT E (polytetrafluoroethylene), agar, and perfluoro ion exchange resin. This electrode catalyst is useful in the production of ozone by electrolyzing water and the production of peroxides by electrolytic water solutions.

The common features of the above patent applications are: The electrolyte is a solid polymer electrolyte (SPPE), usually a perfluorosulfonic acid cation exchange membrane. The cation exchange membrane serves as both an electrolyte and a cathode chamber and an anode chamber in an electrolytic cell. Between the isolation membranes.

The cathode material (catalyst) is usually a platinum group metal, gold, silver, nickel, ruthenium, or a mixture thereof.

Anode materials (catalysts) are usually platinum-based metals, gold or mixtures thereof, and glassy carbon and lead dioxide.

The method for preparing an electrolytic ozone generator using a solid polymer electrolyte as described above involves the following three processes:

First, the electrode composite film is prepared by a hot pressing process. This process procedure is complicated and the conditions are harsh, requiring high pressure and temperature, which increases the manufacturing cost. And if the membrane formed by this process cannot be assembled into the whole generator in time, the moisture content of the membrane will change accordingly due to changes in humidity at room temperature and storage space, which will cause deformation of the electrode / membrane assembly. The second is through penetration chemical plating (ie, electroless plating). This method deposits a layer of electrocatalyst on one or both sides of the ion exchange membrane. The concentration of metal ions, oxidants or reducing agents used in this method is in chemical beryllium Changes occur during the process, and it is difficult to ensure the uniformity of the membrane / electrode assembly prepared each time. The concentration, temperature, and pH of various components must be strictly maintained. Otherwise, it is difficult to ensure the quality of the prepared catalyst.

Third, the preparation of the anode catalyst (such as when using lead dioxide) uses porous titanium as a substrate, and a β-lead dioxide layer is electrodeposited on this substrate. A certain amount of lead ions and other additives need to be guaranteed in this plating solution. Concentration (including various components such as β-lead dioxide particles, PT FE, agar, perfluoro ion exchange resin and the like in the above-mentioned dispersion plating method), and the crystal form of lead dioxide in the coating layer when the PΗ value is changed It has also changed.

Therefore, in the prior art, a method for preparing a catalyst / ion exchange membrane electrode in an electrolytic ozone generator using a solid polymer electrolyte has disadvantages and shortcomings, namely, the preparation process is complicated, the production cost is high, and it is not easy to industrialize produce.

In addition, the electrochemical reactions occurring in the electrolytic ozone generator [see reaction formulas (3) and (4)] raw material water must be consumed when generating ozone and oxygen; the electrochemical reactions [see reaction formulas (1) and ( 2)] protons are consumed in the process. The protons are generated by the anode reaction and migrate to the cathode / cation exchange membrane interface via the cation exchange membrane. Proton migration always occurs in the form of water solvation. As the electrochemical reaction progresses, the amount of raw material water in the anode chamber decreases and the amount of raw material water in the cathode chamber gradually increases. At the same time, with the electrochemical reaction of the electrode, the reaction interface Heat, if no heat dissipation measures are used, the efficiency of ozone generation will be reduced. OBJECTS OF THE INVENTION The purpose of the present invention is to overcome the disadvantages of the complicated electrode preparation process and high production cost in the prior art, and provide an electrolytic ozone generator. The device has a solid polymer electrolyte membrane composite electrode composed of discrete membranes. The component and electrode manufacturing process is simple, the production cost is low, and it is easy to produce on an industrial scale. At the same time, the raw material water in the anode and anode chambers of the electrolytic ozone generator of the present invention is automatically balanced and can output pressure. Ozone above atmospheric pressure has high ozone generation efficiency.

Another object of the present invention is to provide a method for preparing an electrolytic ozone generator in the above-mentioned electrolytic ozone generator. SUMMARY OF THE INVENTION The electrolytic ozone generator of the present invention includes an electrolytic ozone generator, an anode water tank connected to an anode chamber of the ozone generator through an anode circulating water pipe, and a cathode water tank connected to a cathode chamber of the ozone generator through a cathode circulating water pipe.

According to the electrolytic ozone generating device of the present invention, the electrolytic ozone generator includes an independent cation exchange membrane, independent anode catalyst membranes and independent cathode catalyst membranes, which are respectively close to both sides of the cation exchange membrane, An anode porous current collecting sheet on the other side of the anode catalyst membrane, and a cathode porous current collecting sheet on the other side of the cathode catalyst membrane.

2-0. 3 腾 The cation exchange membrane is a perfluorosulfonic acid cation exchange resin commonly used in the prior art, and the anode catalyst membrane is a polytetrafluoroethylene and lead dioxide having a thickness of 0.2-0.3 1-0.2。 The film of the cathode catalyst is a film containing polytetrafluoroethylene and platinum carbon powder with a thickness of 0.1-0.2, the anode porous current collector sheet is coated with a layer containing platinum, A sintered porous titanium sheet of tin and antimony conductive oxide, and the cathode porous current collector sheet is a sintered porous titanium sheet.

In the electrolytic ozone generating device of the present invention, the position of the cathode water tank is higher than that of the anode water tank, and a one-way balancing valve (or on-off solenoid valve) is connected between the cathode water tank and the anode water tank to realize automatic balance of raw material water and make This device can output ozone with pressure. The raw material water in the cathode water tank and the anode water tank is not only the raw material for generating ozone, but also the circulating coolant of the anode and cathode.

The preparation method of the ozone generator in the electrolytic ozone generating device of the present invention includes:

a. Mix 5-15% by weight of platinum carbon powder and polytetrafluoroethylene emulsion (suspension) with an appropriate amount of secondary distilled water in a water bath at about 80 ° C, and then paste into a paste. 0-4 0 repeatedly rolled at a temperature of 0.1-0. 2m m thick film, wherein the weight of polytetrafluoroethylene accounts for 5- 15%, drying the rolled membrane at 50-60 ° C and cutting to the required size to obtain a cathode catalyst membrane (33);

The lead powder b dioxide and PTFE dispersion with an appropriate amount of double distilled water at 8 0 ° (:. a water bath at about stirred into a paste, and then at ³ 0 -4 0 ^e C temperature was repeatedly passed into 0 .2-0 ^.3 mm thick film, in which the weight of polytetrafluoroethylene accounts for 1-5% of the weight of lead dioxide, the laminated film is dried and cut at 50-60 ° C Into the required size to obtain the anode catalyst membrane (3 5);

c. The sintered porous titanium sheet is degreased and pre-treated with 5-20% (by weight) hydrochloric acid, rinsed with distilled water until it is free of chloride ions and dried, and then the surface is coated with platinum and tin. An organic solution of antimony was oxidized in an electric furnace at 500-530 ° C to form a thin layer of conductive oxide containing platinum, tin, and antimony on its surface to obtain an anode porous current collector sheet (36);

d. The sintered porous titanium sheet is degreased and pretreated with 5-20% by weight of hydrochloric acid, rinsed with secondary distilled water to be free of chloride ions, and then dried to obtain a cathode porous current collector sheet (3 2 ).

The ozone generator in the present invention is assembled by combining the independent components mentioned above with other necessary components well known in the art. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic structural diagram of an electrolytic ozone generating device according to the present invention.

FIG. 2 is an assembly schematic diagram of the solid polymer electrolyte membrane composite electrode electrolytic ozone generator (8) in FIG. 1. FIG.

FIG. 3 is an expanded view of FIG. 2.

FIG. 4 is a structural diagram of the one-way balancing valve 1 3. DETAILED DESCRIPTION OF THE INVENTION The electrolytic ozone generator of the present invention is described in further detail below with reference to the drawings: The electrolytic ozone generator of the present invention includes an electrolytic ozone generator 8, an anode water tank 1 connected to the anode chamber of the ozone generator 8 through a circulating water pipe 7, and a cathode connected to the cathode chamber of the ozone generator 8 through a circulating water pipe 6. Water tank 4, one-way balancing valve 1 3, cooling fan 10, 1 1, water level detector 19, 20, 2 1, 2 2 and isolation tube 17.

The electrolytic ozone generator 8 includes a cation exchange membrane 3 4, an anode catalyst membrane 3 5, an anode porous current collector sheet 3 6, an anode chamber frame 3 7, an anode heat sink 3 8, a cathode catalyst membrane 3 3, and a cathode. Porous current collecting sheet 3 2, cathode chamber frame 30, deflector 3 1, anti-corrosion sheet 2 8, deflector clip 2 7, seal 2 9 and bolt 4 0, nut 2 5, washer 2 6, 4 2, Insulating washer 3 9, drainage screw 4 1.

In the electrolytic ozone generating device of the present invention, the anode water tank 18 has a gas collecting surface 18 a at the upper end, so that the anode gas can be discharged quickly without retention. On the gas collecting surface, there is an elongated air duct 18 b, the top of the air duct has an ozone and oxygen outlet 2 4, the air outlet 2 4 has a microporous damping plate 2 3, and the anode water tank is provided with an isolation tube 17. Or titanium tube. The anode gas (ozone, oxygen) and circulating water produced by the anode reaction are introduced into the anode water tank through this tube. The isolation tube 17 is arranged to reduce the contact and dissolution of ozone and the raw material water in the anode water tank. Ozone and oxygen quickly enter the air duct 18 b through the gas collecting surface 18 a, and the gas / water separation is realized at the upper end of the air duct. The separated ozone and oxygen pass through the microporous damping plate 2 3 and are derived from the ozone and oxygen outlets 2 4.

The position of the cathode water tank 4 is higher than that of the anode water tank 18, and the top has a water inlet 2, a water inlet cover 1, and a hydrogen gas outlet 3. The cathode water tank 4 is equipped with a water level detector 19, 20, 21, 22, which is composed of a reed tube 2 2, a float 21, a permanent magnet 20, and a water level detection sealing tube 19. When the water level in the cathode water tank is too high or too low, a signal is output to stop the generator.

The cathode circulation water pipe 6 connects the cathode water tank 4 and the cathode chamber frame 30 to form a water circulation circuit, and the heat generated during the cathode reaction is taken out in time by the water circulation.

The anode circulating water pipe 7 connects the anode water tank 18 and the anode chamber frame 37 to form a water circulation circuit, and the heat generated during the anode reaction is taken out in time by the water circulation.

According to the electrochemical reaction principle of the electrolytic ozone generator, the production of ozone and oxygen in anode reactions 3 and 4 requires the consumption of raw water. The protons produced by the reaction pass through the cation exchange membrane to the cathode in a water-solvated form. Migration, when the electrolytic reaction continues, the raw water in the anode water tank is continuously consumed, and the raw water in the cathode water tank is continuously increased. The raw material water added in the cathode water tank cannot be returned to the anode water tank through the cation exchange membrane in the reverse direction, and eventually the raw water in the anode water tank is completely depleted.

To solve the above problems, the present invention provides a one-way balancing valve between the cathode water tank and the anode water tank. Referring to Figures 1 and 4, the one-way balancing valve 1 3 is composed of an upper valve body 5 1, a diaphragm 50, and a lower valve body 4 9. The upper valve body 5 1 is provided with a cathode water tank interface 4 3, the anode water tank interface 5 2, a damping hole 5 2 a in the interface 5 2, and a ring-shaped sealing lip 4 5; the one-way balanced lower valve body 4 9 is provided with an anode water tank Interface 4

7. Pressure-limiting valve port 4 8. Pressure-limiting plug 4 8 a.

Cathode water tank interface 4 of upper body 5 1 of check valve is connected to cathode water tank 4 and anode water tank interface 5 2 is connected to anode water tank 1 8 and its lower valve body 4 9 is connected to anode water tank 4 7 and anode water tank

1 8 phase connection.

When the ozone generator starts to work, the ozone and oxygen in the anode water tank 18 due to the damping of the microporous damper 2 3 gradually form a pressure P, which passes through the anode water tank interface 5 of the valve body 5 1 on the one-way balance valve. 2 and the anode water tank interface 4 7 of the lower valve body 4 9 are transmitted to both sides of the diaphragm 50. At this time, because the cathode water tank interface 4 3 is also inside the upper valve body 5 1, the raw water is formed from the anode water tank 1 8 to Flow of cathode water tank 4. The water flow through the damping hole 5 2 a of the anode water tank connection 5 2 generates a pressure drop ΔP. The generation of ΔP causes a pressure difference between the two sides of the diaphragm 50, and the diaphragm 50 is biased upward to the valve body 5 1 under this pressure difference until it presses on the annular sealing lip 4 5, and the cathode water tank 4 is cut off at this time. 8 water flow channels with anode water tank. The diaphragm 50 is maintained in this state by the pressure P in the anode water tank 18 being maintained. At this time, the ozone generator device of the present invention can output ozone and oxygen at a pressure P.

When the ozone generator stops working, the pressure P gradually disappears. If the water level of the cathode water tank 4 is higher than the water level of the anode water tank 18, the diaphragm 50 will be biased downward to the valve body 4 9 by the water level pressure difference, and the cathode water tank 4 and The anode water tank 1 8 is connected again through a one-way balancing valve, and the water levels in the cathode and anode water tanks will gradually return to equilibrium.

The pressure-limiting plug 4 8 a of the one-way balance valve will be opened when the pressure in the anode water tank 18 is too high, and it will perform pressure-limiting protection. In addition to the one-way balancing valve provided between the cathode water tank 4 and the anode water tank 18, the electrolytic ozone generating device of the present invention can also be provided with an on-off solenoid valve, which can also achieve the purpose of water balance. On-off solenoid valve When the device is started, the channels of the cathode and anode water tanks are closed. When the device is stopped, the on-off type solenoid valve is connected to the channels of the cathode and anode water tanks.

The cooling fans 10, 1 1 are installed at the lower part of the electrolytic ozone generator 8, and the cooling air blows upward through the fins 38, the anode water tank 18, and the cathode water tank 4 to assist the heat dissipation.

The ozone generator in the present invention is cold-pressed by using the following independent membranes prepared through different processes, respectively.

The cation exchange membrane 3 4 used in the present invention is a perfluorinated transverse acid cation exchange membrane (model 1 1 7) produced by DuPont of the United States. The treatment process is: Soaking with 10% hydrogen peroxide at 80-90 ° C for one hour to remove organic impurities in the membrane. After rinsing with a large amount of secondary distilled water at about 60 ° C, immerse in 2 0 mol / 1 sulfuric acid at 80 0-9 0 ° C for half an hour to remove a small amount of metal ions, and finally use a large amount of about 60 ° C Rinse the sub-distilled water to neutrality, and store in the sub-distilled water for assembly.

The preparation process of the cathode catalyst membrane 3 3 is as follows: platinum carbon powder (2 0 0 mesh sieved) containing 5 to 15% by weight of platinum is sieved with polytetrafluoroethylene emulsion (suspension) and an appropriate amount of secondary distilled water Stir in a water bath at about 80 ° C to form a paste, and then repeatedly roll it to a thickness of 0.1-0 · 2 mm at a temperature of 30-4 0 "C. Among them, polytetrafluoroethylene accounts for the weight of platinum carbon powder. 5-15% by weight. the rolling diaphragm through 5 0 -6 0 ^e C dry, and cut into a desired size, to be assembled with the cathode catalyst membrane thus produced in a process It has porous conductive properties. Hydrogen generated at the catalyst membrane / cation exchange membrane contact interface and water accompanied by proton migration can smoothly enter the cathode chamber through the micropores of the cathode catalyst membrane.

The anode catalyst membrane 3 5 is prepared by mixing lead dioxide powder (180 mesh sieved) with polytetrafluoroethylene emulsion (suspension) and an appropriate amount of twice-distilled water at about 80 ° C. to form a paste. 0 -4 0. (Rolled at a temperature of 0.2-0.3 mm film. Polytetrafluoroethylene accounts for 1-5% of the weight of lead dioxide powder. After drying the film at 50-60 ^e C Cut to the required size and save it for use during assembly. The anode catalytic membrane produced by this process has porous conductivity, and ozone and oxygen generated at the contact surface of the cation exchange membrane of the anode catalyst membrane I can pass through the anode catalyst smoothly. Diaphragm micropores Electrode chamber; At the same time, the raw material water can migrate backward through the membrane pores and enter the anode catalyst membrane / cation exchange membrane reaction interface to participate in the anode reaction. Part of the raw material water moves to the cathode compartment along with the protons through the cation exchange membrane.

The preparation process of anode porous current collector sheet 3 6 is: sintered porous titanium sheet (maximum pore size is 2 6 〃m, air permeability is 1 19 M ³ / m ^2. Hk P a) after degreasing and using 5- After 20% (by weight) hydrochloric acid is etched and pre-treated, it is rinsed with double distilled water to be free of chloride ions and then dried. Then the surface is coated with an organic solution containing platinum, tin, and antimony, and oxidized in an electric furnace at 500-5 30 ° C to form a thin layer of conductive oxide containing platinum, tin, and antimony on the surface to prevent The porous current collector is passivated when passing through the anode current. The porous current collector sheet made by the above process has the functions of electrical conduction and gas-liquid conduction (that is, gas products can leave the electrode reaction interface through the current collector sheet; and raw water can enter the electrode reaction interface through the current collector sheet). The weight percentage of the organic solution containing platinum, tin, and antimony described herein is:

Concentrated hydrochloric acid _{3 - 9%;. H 2} P t Cl 6 6H 2 0 1 - 2%;. S n Cl 4 5H 2 0 5 - 1 0%; S b Cl 3 0 .5 - 1 .5%; C ₄ H ₉ 0H 6 0-9 0%.

The cathode porous current collector sheet 3 2 is prepared by sintering a porous titanium sheet (with a maximum pore size of 26 μm and an air permeability of 1 1 9 M ³ / m ² ■ hk P a) after degreasing and using 5-2 Etching with 0% by weight of hydrochloric acid, rinsing with double distilled water until there are no chloride ions, drying, storing, and using it for assembly. The porous current collecting sheet has the functions of conduction and gas-liquid conduction.

The deflector 3 1 is a metal titanium plate, and the parts with vertical and horizontal grooves are formed after processing, as shown in FIG. 3. The deflectors are respectively assembled in the cathode and anode frames to form the cathode and anode compartments. Its vertical and horizontal groove faces face the cathode and anode porous current collectors, respectively. The vertical and horizontal grooves of the deflector 31 can contain raw water, and the raw water and gas products convect and diffuse in the groove. The deflector has a conductive cooling function.

The anode chamber frame 37 is made of polytetrafluoroethylene and processed into independent components, as shown in Figure 3. The frame is provided with upper and lower gas nozzles, and is respectively connected with the anode water tank 18 to form a raw material water circulation circuit in the anode room. With the rise of the gas (ozone, oxygen) generated by the anode reaction and the temperature difference between the temperature of the raw material water in the anode chamber and the temperature of the anode water tank as the motive force, an automatic circulation of water is formed to play a cooling role.

The cathode chamber frame 3 0 is made of organic glass or ABS plastic, as shown in Figure 3. The framework There are upper and lower gas nozzles, which are respectively connected with the cathode water tank 4 to form a raw material water circulation circuit in the cathode chamber. With the rise of the gas (hydrogen) generated by the cathode reaction and the temperature difference between the temperature of the raw material water in the cathode chamber and the temperature of the cathode water tank as the motive force, an automatic circulation of water is formed to play a cooling role.

The gasket 2 9 is made of silicone rubber material, which ensures the sealing of the gas and raw water generated in the yin and yang chambers.

Anti-corrosive sheet 2 8 Select titanium metal material to prevent the spoiler from corrosion. The deflector clamp 2 7 is made of hard alloy aluminum plate, and is used as the generator's cathode and anode to connect with external DC power supply.

The ozone generator of the present invention is made of the above components by cold pressing assembly method, and the assembly sequence is: anode fins 3 8, deflectors 2 7, anticorrosive sheets 2 8, seals 2 9, deflectors 3 1. Anode chamber frame 3 7, Seal 2 9, Anode porous current collector 3 6, Anode catalyst diaphragm 3 5, Cation exchange membrane 3 4, Cathode catalyst diaphragm 3 3, Cathodic porous current collector 3 2, Seal The pad 2 9, the deflector 3 1, the cathode chamber frame 30, the gasket 2 9, the anticorrosive sheet 2 8, the deflector clamp 27, and then fasten with bolts, nuts, washers, and insulating washers.

The electrolytic ozone generating device of the present invention has a simple preparation process and convenient assembly. Compared with the prior art ozone generating device, the cost of the device of the present invention can be reduced by 30 to 50%. And the raw material water in the cathode and anode water tanks of the electrolytic ozone generating device of the present invention can be automatically balanced, and the highest output can be higher than atmospheric pressure 0.1 Pa. The device can run stably for a long time, and the ozone generation efficiency is high. The following table is a comparison of the ozone life-saving efficiency between the device of the present invention and some electrolytic ozone generators of the prior art: cell voltage current density ozone generation efficiency reference

(V) (A / cm ² ) (%)

The invention 3. 5 1. 5 18-20

Prior art 1 3. 6 1. 0 16 US4927800 Prior art 2 4. 0 8 JP43390 / 90 Prior art 3 3. 3 1. 0 13 JP20488 / 91 Prior art 4 4. 0 7 JP43389 / 90 Prior art 5 0 13-16 US5203972 Example: Example 1: Preparation of electrolytic ozone generator (8) a. Preparation of cation exchange membrane ( ³ 4): 1 1 7 type perfluorosulfonic acid cation exchange Membrane (product of DuPont) Boil with 10% hydrogen peroxide at 90 ° (for one hour to remove the organic impurities in the membrane, rinse with a large amount of 60 ^e C double distilled water, and then put in 80 V 2 mol Soak in / 1 sulfuric acid for half an hour to remove a small amount of metal ions. Finally, rinse with a large amount of 60 ° C secondary distilled water to neutrality, and store in secondary distilled water for assembly.

b. Preparation of cathode catalyst membrane ( ³³ ): platinum carbon powder ( ²⁰⁰ mesh sieved) containing 6% (wt) platinum with polytetrafluoroethylene emulsion (suspension) and appropriate amount of secondary distilled water at 8 Stir in a water bath around 0 ^e C to a paste, then at 3 5. (: Repeatedly rolled into a film with a thickness of 0.1 mm at the temperature. The weight of polytetrafluoroethylene accounts for 10% of the weight of the platinum carbon powder. The rolled film is dried at 60 ° C and cut Into the required size, ready for assembly.

C. Preparation of anode catalyst membrane (35): β-lead dioxide powder (180 mesh sieved), polytetrafluoroethylene emulsion (suspension) and appropriate amount of secondary distilled water are stirred at about 80 ° C The paste was then rolled into a 0.2 mm film at 40 ° C. Among them, polytetrafluoroethylene accounts for 2% of the weight of lead dioxide powder. After drying at 5 5 'C, the diaphragm is cut to the required size and stored for use during assembly.

d. Preparation of anode porous current collector sheet (3 6): Sintered porous titanium sheet (maximum pore size is 2 6 M, air permeability is 1 1 9 M ³ / m ^2. hk P a) after degreasing and using 1 After 0% hydrochloric acid etching and pre-treatment, rinse with distilled water until there are no chloride ions, and then dry. Then the surface is coated with an organic solution containing platinum, tin, and antimony, and oxidized in an electric furnace at 5 20 C to form a thin layer of conductive oxide containing platinum, tin, and antimony on the surface. The weight percentage of the organic solution containing platinum, tin, and antimony described herein is:

Of concentrated hydrochloric acid _{_{5%;. H 2 P t}} Cl 6 6H 2 0 1%;. S n Cl 4 5H 2 0 8%; S b Cl 3 1. 0%; C 4 H 9 OH 85% ₀

e. Preparation of cathode porous current collector sheet ( ³ 2): Sintered porous titanium sheet (maximum pore size is 26 μm, air permeability is 1 1 9 M ³ / m ² .hk P a), after degreasing, use 1 Etching with 0% hydrochloric acid, rinsing with distilled water until there are no chloride ions, drying, storing, and using it for assembly.

Cut the five components prepared above into 8 cm ² size squares, cooperate with other components, follow the anode heat sink (3 8), deflector (2 7), anti-corrosion sheet (2 8), and gasket (2 9 ), Deflector (3 1), anode chamber frame (3 7), gasket (2 9), anode porous current collecting sheet (3 6), anode catalyst membrane ( ³ 5), cation exchange membrane (3 4 ), Cathode catalyst diaphragm ( ³ 3), cathode porous current collector (3 2), seal (2 9), deflector ( ³¹ ), cathode chamber frame ( ³⁰ ), seal (2 9) The anti-corrosion sheet (2 8) and the deflector splint (2 7) are arranged in order. The deflector (3 1) is made of a 10 mm thick metal titanium plate, and one side is evenly distributed with 7 widths 2. 5 mm, 6 mm deep grooves; the cathode chamber frame (30) is injection-molded with plexiglass material, and there is a space of 3 1 X3 1 X9 mm ³ in the frame, and the inner diameter of the upper and lower gas-water connection nozzles is ⁴ mm; the anode The chamber frame (37) is made of polytetrafluoroethylene, and its shape, size and inner volume are exactly the same as those of the cathode chamber frame (30); 28) are made of commercially pure titanium, a thickness of 0 8 mm, an area of 4 0 X4 0 mm ^2;. Clamp guide (27) is a carbide of aluminum, having a thickness of 8 mm, an area of 6 0 X6 0 mm ² ; then use bolts (40), nuts (2 5), washers (2 6, 4 2) and insulation washers (3 9) to fasten to obtain the electrolytic ozone generator (8) of the present invention. Example 2: ozone generator, (8) the preparation of a preparation of a cation exchange membrane ⁽³⁴⁾ is: The 117 perfluorosulfonic acid type cation exchange membrane (product of DuPont Co.) with 10% peracetic Hydrogen oxide was immersed in 80 ° C for one hour to remove organic impurities in the membrane. After rinsing with a large amount of 60 ° C secondary distilled water, it was immersed in 802 mol / 1 sulfuric acid for half an hour to remove a small amount of The metal ions are finally rinsed with a large amount of 60 ^e C secondary distilled water to neutrality, and stored in the secondary distilled water for assembly. D. Preparation of cathode catalyst membrane (3 3): Platinum carbon powder (200 mesh sieve) containing 12% (weight) of platinum was mixed with polytetrafluoroethylene emulsion (suspension) and an appropriate amount of secondary distilled water in Stir in a water bath at about 80 ° C to form a paste, and then repeatedly roll into a 0.2 mm thick film at 40 ° C. The weight of polytetrafluoroethylene accounts for 15% of the weight of platinum carbon powder. The rolled membrane is dried at 60 ° C and cut to the required size for use during assembly.

C. Preparation of anode catalyst membrane ( ³ 5): Stir the lead dioxide powder (180 mesh through a sieve) with polytetrafluoroethylene emulsion (suspension) and an appropriate amount of secondary distilled water at about 80 ° C to form a paste. Then at 3 5. (: Rolled into a 0.2 mm film at temperature. Polytetrafluoroethylene accounts for 1% of the weight of lead dioxide powder. The film is dried at 60 ° C and cut to the required size for storage. To be used when assembling.

d. Preparation of anode porous current collector sheet (3 6): Sintered porous titanium sheet (maximum pore size is 2 6 Mm, air permeability is 1 1 9 M ³ / m ^2. hk P a) after degreasing and using 1 After 0% hydrochloric acid etching and pre-treatment, rinse with distilled water until there are no chloride ions, and then dry. Then the surface is coated with an organic solution containing platinum, tin, and antimony, and oxidized in a 500 ° (:) electric furnace to form a thin layer of a conductive oxide containing platinum, tin, and antimony on the surface. The weight percentages of organic solutions containing platinum, tin, and antimony are:

Concentrated hydrochloric acid _{_{9%; H 2 P t Cl}} 6 .6H 2 0 2%; S n Cl 4 .5H 2 0 10%; S b Cl 3 1.0%; C 4 H 9 OH 78% 0

e. Preparation of cathode porous current collector sheet (3 2): Sintered porous titanium sheet (maximum pore size is 26 μm, air permeability is 1 1 9 M ³ / m ² .hk P a), after degreasing, use 1 0 «¾ Hydrochloric acid etching, rinse with distilled water until there are no chloride ions, dry, save, and use it during assembly.

According to the same method as in Example 1, the components prepared above and other components were assembled into the electrolytic ozone generator ( ⁸ ) of the present invention. Example 3: Preparation of electrolytic ozone generator (8) a. Preparation of cation exchange membrane (3 4): A 1 1 7 type perfluorosulfonic acid cation exchange membrane (product of DuPont) was used at 10% Soak hydrogen oxide at 8 5 ° C for one hour to remove organic impurities in the membrane. After rinsing with a large amount of secondary distilled water at 60 ° C, immerse it in sulfuric acid at 80 "C 2 mol / 1 for half an hour to remove a small amount of metal ions. Finally, rinse with a large amount of secondary distilled water at 60 ° C until Neutral, stored in re-distilled water for use when assembled.

b. Preparation of cathode catalyst membrane (3 3): platinum carbon powder (2) containing 10% by weight of platinum (2

0 0 mesh sieved) with polytetrafluoroethylene emulsion (suspension) and an appropriate amount of secondary distilled water at 80 ° (: left and right water bath to stir into a paste, and then repeatedly rolled to 0 at the temperature of 0. 1 mm thick film. The weight of PTFE is 5% of the weight of platinum carbon powder. The rolled film is dried at 60 ° C and cut to the required size for use during assembly.

C. Preparation of the membrane an anode catalyst ^(35): A mixture of β - dioxide lead powder (180 mesh sieve) and PTFE emulsion (suspension) and an appropriate amount of double distilled water was stirred at about 8 0 ° C Make a paste and then at 30. (: Rolled into a 0.3 mm film at temperature. Of which polytetrafluoroethylene accounts for the weight of lead dioxide powder

1.5%. The membrane is dried at 6CTC and cut to the required size for storage and used during assembly.

d. Preparation of anode porous current collector sheet (3 6): Sintered porous titanium sheet (maximum pore size is 2 6 Mm, air permeability is 1 1 9 M ³ / m ^2. hk P a) after degreasing and using 1 After 0% hydrochloric acid etching and pre-treatment, rinse with distilled water until there are no chloride ions, and then dry. Then the surface is coated with an organic solution containing platinum, tin, and antimony, and oxidized in an electric furnace at 520 ° C to form a thin layer of conductive oxide containing platinum, tin, and antimony on the surface. The weight percentage of the organic solution containing platinum, tin, and antimony described herein is:

Of concentrated hydrochloric acid, _{_{3%; H 2 P t Cl}} 6 .6H 2 0 1.5%; S n Cl 4, 5H 2 0 5%; S b Cl 3 0.5%; C 4 H 9 OH

90% _o

e. Preparation of cathode porous current collector sheet (3 2): Sintered porous titanium sheet (maximum pore size is 26 μm, air permeability is 1 1 9 M ³ / m ² .hk P a), after degreasing, use 1 Etching with 0% hydrochloric acid, rinsing with distilled water until there are no chloride ions, drying, storing, and using it for assembly.

According to the same method as in Example 1, the components prepared above and other components were assembled into the electrolytic ozone generator ( ⁸ ) of the present invention. Embodiment 4: Assembly and application of the electrolytic ozone generating device of the present invention The electrolytic ozone generator (8) prepared in Example 1 and the following components are used:

1 500 ml cathode water tank (4), 1 200 ml anode water tank (1 8), one-way balanced wide (1 3), cooling fan (1 0, 1 1), anode circulating water pipe (7) The cathode circulation water pipe (6), the water level detector (19, 20, 21, 22) and the isolation pipe (17) are installed according to methods known in the art to form the electrolytic ozone generating device of the present invention.

When the electrolytic ozone generator of this embodiment is operated at a current density of 1.5 A / cm ² , the generator tank voltage is ³ · 5 ± 0.1 V, and the ambient temperature is 2 5. (: When left and right, continuous operation for 24 hours, the raw material water temperature in the anode and anode water tanks can be maintained at about 30 ° C, and the ozone generation efficiency is 18.

Ozone can be output from the anode water tank at a pressure higher than atmospheric pressure 0.8 Mp a.

Claims

Rights request

An electrolytic ozone generating apparatus comprises an electrolytic ozone generator (8), an anode tank (18) is connected to the anode chamber through the anode circulation pipe ⁽⁷⁾ and the ozone generator ^(8), the water circulating through the cathode ( ⁶ ) a cathode water tank ( ⁴ ) connected to the cathode chamber of the ozone generator ( ⁸ ), which is characterized by:

The electrolytic ozone generator (8) includes independent cation exchange membranes (3 4), independent anode catalyst membranes (3 5) respectively adjacent to both sides of the cation exchange membrane (3 4), and independent cathode catalyst membrane (33), a porous anode current collecting plate on the other side of the membrane an anode catalyst (35) in ^(36), a porous cathode current collector of the cathode catalyst on the other side of the diaphragm ⁽³³⁾ is Tape out ( ³ 2).

2. The electrolytic ozone generator according to claim 1, characterized in that: the cathode catalyst membrane (33) in the electrolytic ozone generator (8) contains platinum carbon powder and polytetrafluoroethylene, The platinum carbon powder contains 5 to 15% by weight of platinum, and the weight of polytetrafluoroethylene accounts for ^{5 to} 15% of the weight of the platinum carbon powder.

3. The electrolytic ozone generator according to claim 2, characterized in that the particle size of the platinum carbon powder in the cathode catalyst membrane (33) is smaller than 200 mesh.

4. The electrolytic ozone generating device according to claim 2, wherein the thickness of the cathode catalyst membrane (33) is 0.1 to 0.2 mm.

5, according to claim 1, the electrolytic ozone generating apparatus, wherein: the ozone generator, the anode catalyst of the diaphragm ⁽⁸⁾ ⁽³⁵⁾ comprising lead dioxide and polytetrafluoroethylene.

6. The electrolytic ozone generating device according to claim 5, wherein the weight of polytetrafluoroethylene in the anode catalyst membrane (35) is 1 to 5% of the weight of lead dioxide.

7. The electrolytic ozone generator according to claim 5 or 6, characterized in that the particle size of the lead dioxide used in the anode catalyst membrane (35) is smaller than 180 mesh.

8. The electrolytic ozone generator according to claim 5 or 6, characterized in that the lead dioxide used in the anode catalyst membrane (35) is β-lead dioxide.

9. The electrolytic ozone generating device according to claim 7, wherein the lead dioxide used in the anode catalyst membrane (35) is β-lead dioxide.

10. The electrolytic ozone generator according to claim 5 or 6, characterized in that the thickness of the anode catalyst membrane (3 5) is 0.2-0.3 mm.

11. The electrolytic ozone generating device according to claim 8, wherein the thickness of the anode catalyst membrane (3 5) is 0.2 to 0.3 mm.

12. The electrolytic ozone generating device according to claim 9, wherein the thickness of the anode catalyst membrane (3 5) is 0.2 to 0.3 mm.

13. The electrolytic ozone generating device according to claim 1, characterized in that: the anode porous current collecting sheet (36) in the electrolytic ozone generator (8) is coated on the surface with a layer containing platinum, Sintered porous titanium sheet of tin and antimony conductive oxide.

14. The electrolytic ozone generator according to claim 1, wherein the electricity The solution type ozone generator (8) further comprises a diversion made of metal titanium with grooves uniformly arranged on one side.

15. The electrolytic ozone generator according to claim 1, wherein:

The anode water tank (18) has a gas collecting surface (18a) on the upper end, an elongated gas tube (1b) on the gas collecting surface, and an ozone and oxygen outlet (2) on the top of the gas tube (1b). 4), the ozone and oxygen outlets (2 4) are provided with microporous damping plates (2 3), the anode water tank (1 8) is provided with an isolation tube (1 7), and the anode water tank (1 8) passes through the anode circulation tube ( ⁷ ) ⁽³⁷⁾ connected to the anode compartment frame formed water circulation circuit;

16. The electrolytic ozone generating device according to claim 1, characterized in that: the position of the cathode water tank ( ⁴ ) is higher than that of the anode water tank (18), and a water inlet (2) and a water inlet cover are provided on the top of the cathode water tank ( ⁴ ). (

1), hydrogen outlet (3), cathode water tank (4) is equipped with a water level detector (19, 20, 21,

2 2). The cathode water tank ( ⁴ ) is connected to the cathode chamber frame ( ³⁰ ) through a cathode circulation pipe ( ⁶ ) to form a water circulation circuit.

17. The electrolytic ozone generator according to claim 1, characterized in that:

A one-way balancing valve (1 3) is arranged between the cathode water tank ( ⁴ ) and the anode water tank (1 8). The one-way balancing valve (1 3) is composed of an upper valve body (5 1) and a diaphragm (50). The lower valve body (49) is composed of the upper valve body (51) provided with a cathode water tank interface (4 3), an anode water tank interface ( ⁵ 2), and an anode water tank interface (5 2) with a damping hole (5 2). a), ring-shaped sealing lip (4 5); one-way balanced lower valve body (4 9) is provided with anode water tank connection (4 7), pressure limiting valve port (4 8) and pressure limiting plug (4 8 a).

18. The electrolytic ozone generator according to claim 1, characterized in that: an on-off solenoid valve is provided between the cathode water tank ( ⁴ ) and the anode water tank (18).

19. A method for preparing an electrolytic ozone generator (8) according to claim 1, comprising: Include:

a. Stir the platinum carbon powder and polytetrafluoroethylene emulsion containing 5-1 to 5 (weight) platinum with an appropriate amount of secondary distilled water in a water bath of about 80 ^e C, and then paste it in a 30-4 0 " It is repeatedly rolled into a film with a thickness of 0.1-0.2mm at a temperature of C, in which the weight of polytetrafluoroethylene accounts for 5 to 15% of the weight of the platinum carbon powder, and the rolled film is baked at 50 to 60 ° C. Dried and cut to the required size to obtain a cathode catalyst membrane (3 3);

b. Place dioxide and lead powder PTFE dispersion with an appropriate amount of double distilled water was stirred into a paste at about 80 'C in a water bath, and then repeatedly rolling at 0 to ³ 0 -4 0 ° C temperature. 2-0.3 mm thick film, in which the weight of polytetrafluoroethylene accounts for 1-5% of the weight of lead dioxide, the rolled film is dried at 50-60 ° C and cut into The required size to obtain the anode catalyst membrane (3 5);

c. The sintered porous titanium sheet is degreased and pre-treated with 5 "20% by weight of hydrochloric acid, rinsed with secondary distilled water to be free of chloride ions and dried, and then the surface is coated with platinum and tin. An organic solution of antimony is oxidized in a 500-500 electric furnace to form a thin layer of a conductive oxide containing platinum, tin, and antimony on the surface to prepare an anode porous current collector sheet (36);

20. The method for preparing an ozone generator according to claim 19, wherein the particle size of the platinum carbon powder used in preparing the cathode catalyst membrane (33) is less than 200 mesh.

21. The method for preparing an ozone generator according to claim 19, wherein the particle size of the lead dioxide used in preparing the anode catalyst membrane (35) is less than 180 mesh.

2 2. The method for preparing an ozone generator according to claim 19 or 21, wherein the lead dioxide used in preparing the anode catalyst membrane (3 5) is (3-dioxide) lead.

23. The method for preparing an ozone generator according to claim 19, characterized in that the weight of the organic solution containing platinum, tin and antimony used in preparing the anode porous current collector sheet (36) Hundred groups are: 3-9% concentrated hydrochloric acid; H ₂ P _t Cl ₆ .6H ₂ 0 1-2%; S _n Cl ₄ .5H ₂ 0 5-10%; S _b Cl ₃ 0 .5-1.5%; C ₄ H ₉ OH 60-90% _o

24. The method for preparing an ozone generator according to claim 19, wherein the maximum pore diameter of the sintered porous titanium sheet used in preparing the anode porous current collector sheet (3 6) is 2 6 m, air permeability is 119M ³ / m ² .h.kPa ₀

25. The method for preparing an ozone generator according to claim 19, wherein the maximum pore diameter of the sintered porous titanium sheet used in preparing the cathode porous current collector sheet (3 2) is 2 6 μχη, air permeability is 119M ³ / m ² .h.kPa ₀