CN112048732A

CN112048732A - Continuous flow gallery type H based on plug-in capsule cathode2O2Synthesis reactor

Info

Publication number: CN112048732A
Application number: CN202010975848.1A
Authority: CN
Inventors: 李楠; 李欣萍
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2020-09-16
Filing date: 2020-09-16
Publication date: 2020-12-08
Anticipated expiration: 2040-09-16
Also published as: CN112048732B

Abstract

The invention discloses a continuous flow gallery type H based on a plug-in capsule cathode₂O₂The synthesis reactor is characterized in that a pluggable capsule cathode is directly plugged for use and fixed through a bottom clamping groove, anode plates are fixed through bottom and side clamping grooves and staggered to form a turning gallery, all the anode plates are connected to the positive pole of a direct current power supply, and all the capsule cathodes are connected to the negative pole of the direct current power supply. The inlet of the reactor is connected with the outlet of an electrolyte storage tank, the electrolyte continuously enters the reactor at a certain flow speed through a peristaltic pump, and the electrolyte flows back in the reactor gallery to continuously take away the H synthesized by the reactor₂O₂The outlet of the reactor can be connected with H₂O₂Storage tank or H₂O₂An application device. The invention can realize high-efficiency continuous H production₂O₂And H₂O₂The product is ready for use.

Description

Continuous flow gallery type H based on plug-in capsule cathode2O2Synthesis reactor

Technical Field

The invention relates to the field of electrochemical synthesis, in particular to a continuous flow gallery type H based on a pluggable capsule cathode₂O₂A synthesis reactor.

Background

Hydrogen peroxide (H)₂O₂) Is an industrial chemical, is widely used in the water and wastewater industries, and can be used for advanced oxidation and disinfection treatment of complex organic chemicals and emerging pollutants. 95% of H in the world at present₂O₂Is produced by the anthraquinone oxidation process, but the process consumes a large amount of energy and requires the use of compounds with potential carcinogenic risks as catalysts, and is a non-green and environmentally friendly process.

Electrochemical production of H by two-electron oxygen reduction₂O₂Is expected to become a new method capable of replacing the traditional anthraquinone method, and the method has various advantages. The carbon material which is the first choice as the carrier of the electric catalyst at present has large specific surface area, good thermal and chemical stability and low price, and is used for reducing oxygen into H through two electrons₂O₂Is excellent. In all electrode configurations, the air diffusion electrode is due to its higher H₂O₂Have generated great attention. The air diffusion electrode consists of an air diffusion layer, a current collector and a catalyst layer, wherein in the electrolysis process, the air diffusion layer is in contact with air, the catalyst layer is in contact with electrolyte, oxygen in the air is diffused from the diffusion layer to enter the catalyst layer and is combined with hydrogen ions to react under the catalysis of active sites to generate H₂O₂。

Laboratory H at present₂O₂Electrosynthesis is usually carried out in reactors of several tens to several hundreds of milliliters, usually in batch mode, requiring thorough stirring to ensure rapid mass transfer between the cathode and anode. Electrocatalytic synthesis of H₂O₂Has focused on the scalability of the reactor unit to achieve synthesis on a scale that is shifted from laboratory to industrial relevance. In the extension of the reactor, it is essential to ensure sufficient electrode area and rapid mass transfer. It may also be desirable to increase the catalyst material at concentrated H₂O₂In the stability or incorporation into the flow system to remove H from the electrode in time₂O₂。

Disclosure of Invention

The invention aims to solve the problems in the prior art and designs a continuous flow gallery type H based on a pluggable capsule cathode₂O₂A synthesis reactor. The device has the characteristics of simple structure, low manufacturing cost, strong expansibility and the like, and can effectively improve H₂O₂Synthesis efficiency, H produced by flexible configuration adjustment₂O₂Concentration and continuous production of H₂O₂And H₂O₂The product is ready for use. The plug-in capsule cathode is convenient for direct use, flexible arrangement and combination, disassembly and assembly, replacement and the like, and device expansion and H can be realized by adjusting the number of electrodes₂O₂And (4) adjusting the concentration.

The purpose of the invention is realized by the following technical scheme: continuous flow gallery type H based on plug-in capsule cathode₂O₂The synthesis reactor adopts a plug-in capsule cathode, anode plates are staggered to form galleries, and adopts continuous flow liquid inlet to generate H₂O₂Is continuously accumulated with the electrolyte flow in the gallery and is collected at the end.

The pluggable capsule cathode is an electrode which is characterized in that a cylindrical air diffusion cathode made of carbon black-graphite-PTFE is adopted, a catalyst layer and a gas diffusion layer are respectively rolled to two sides of a stainless steel net and then rolled into a cylinder to form an inner cavity, the gas diffusion layer is arranged on the inner side of the cylinder, and the catalyst layer is arranged on the outer side of the cylinder. The connection part of the side edge of the winding drum is bonded and fixed through a specially-made long I-shaped clamp, the bottom of the winding drum is sealed by an end enclosure, and the capsule electrode is integrated into a whole and can be directly plugged and pulled for use.

The anode plate is fixed by clamping grooves at the side and the bottom of the reactor, and the anode plate can be made of noble metals (such as platinum group metals), heavy metals (such as Ni and Co), metal alloys, metal composite metal oxides (such as titanium iridium electrodes and titanium ruthenium electrodes of titanium-based mixed oxides) and the like.

The anode plates are fixed in grooves on the side and the bottom of the reactor in a staggered manner to form galleries, the plug-in capsule cathodes are fixed through clamping grooves on the bottom of the reactor, the inner side of the cylinder is in direct contact with air, the outer side of the cylinder is in contact with electrolyte, and the capsule cathode rows and the anode plates in the reactor are orderly and alternately arranged.

The invention continuously feeds liquid from one side of the reactor, the electrolyte flows to the other side along the galleries formed by the anode plates in a staggered way and collects the generated H in the process₂O₂And collected on the other side of the reactor.

A plurality of anode plates are respectively connected to the positive pole of a direct current power supply, and a plurality of plug-in capsule cathodes are respectively connected to the negative pole of the direct current power supply.

Advantageous effects

1. The device selects the plug-in capsule cathode rolled by the carbon black-graphite-PTFE air diffusion cathode, has simple structure and flexible arrangement, is convenient for direct use, disassembly, assembly and replacement, and can ensure enough cathode surface area in the reactor.

2. The device expansibility is strong, and different scales can be realized by matching with plug-in capsule cathodes with different sizes or quantities.

3. The device adopts a plug flow type gallery, stirring is not needed, and the electrolyte continuously flows in the gallery and continuously takes away the synthesized H₂O₂Continuously accumulated and collected or utilized at the end of the reactor to promote H₂O₂The continuous synthesis of (2).

4. System for H₂O₂The concentration can be controlled by adjusting the current, the electrifying time, the number of the cathode and the anode, the ratio of the area of the capsule cathode to the volume of the reactor, the hydraulic retention time of the electrolyte and the like, the operation is simple and convenient, and the adjustable range is larger.

5. The system has low cost, and the organic glass and the graphite-carbon black-PTFE air diffusion cathode are cheap and easy to obtain.

Drawings

FIG. 1 is a schematic structural diagram of a pluggable capsule cathode;

FIG. 2 is a continuous flow gallery type H based on a plug-in capsule cathode₂O₂A synthesis reactor unit top view;

FIG. 3 is a continuous flow gallery type H based on a plug-in capsule cathode₂O₂A schematic diagram of the synthesis reactor apparatus operation;

reference numerals: 1-air diffusion layer, 2-stainless steel mesh, 3-catalyst layer, 4-reactor tank body, 5-liquid inlet, 6-liquid outlet, 7-anode plate, 8-capsule cathode, 9-direct current power supply and 10-gallery type H₂O₂Synthesis reactor, 11-electrolyte tank, 12-peristaltic pump, 13-H₂O₂And (4) storage tank.

Detailed Description

The invention is further described below with reference to the following figures and specific examples.

The invention provides a continuous flow gallery type H based on a plug-in capsule cathode₂O₂A synthesis reactor unit. The device consists of a reactor tank body 4, a plug-in capsule cathode 8 and an anode plate 7, wherein the anode plate 7 is arranged in a staggered mode to form galleries, and the expansion and the amplification of the reactor can be realized by using electrodes with different quantities and specifications. The front end of the reactor is continuously pumped with electrolyte by a peristaltic pump 12, and the rear end is provided with H₂O₂By collecting or using means 13 for H₂O₂To promote the system to continuously and efficiently synthesize H₂O₂。

Referring to fig. 1, the device employs a plug-in capsule cathode consisting of a diffusion layer 1, a catalytic layer 3 and a stainless steel mesh 2 serving as a current collector. The catalyst layer 3 is formed by mixing graphite, carbon black and PTFE emulsion, and the mixture is stirred to be pasty and rolled to one side of the stainless steel net 2; the diffusion layer 1 is prepared from carbon black and PTFE emulsion in a mass ratio of 4: 9 are mixed and rolled onto the other side of the stainless steel mesh 2 to finally form a sheet-shaped cathode having a total thickness of about 1 mm. The sheet cathode is cut into a proper size, the air diffusion layer 1 is arranged inside the sheet cathode, the catalyst layer 3 is arranged outside the sheet cathode, the sheet cathode and the catalyst layer are rolled into a cylinder, the joint is bonded and fixed through a specially-made long I-shaped clamp, the bottom of the sheet cathode is sealed by a seal head, the pluggable electrode is integrated into a whole, and the pluggable electrode can be used after being directly inserted into a reactor clamping groove for fixing.

Referring to FIG. 2, the main body of the device is made of organic glass, the anode plates 7 are fixed by the clamping grooves on the side and bottom of the reactor, the anode plates are arranged in a staggered manner to form folding galleries, the electrolyte enters from the inlet, flows in the galleries and can take away the generated H at the same time₂O₂Collected or utilized to the end while achieving mass transfer without additional agitation. The cathode is directly inserted into the clamping groove for fixing by adopting a plug-in capsule cathode 8, the anode plate 7 and the capsule cathode 8 are orderly arranged in the reactor, and the distance between the cathode and the anode is adjustable. The reactor can be realized by using capsule cathodes with different diameters, different heights and different numbersAmplification and expansion. The assembled reactor is connected with a direct current power supply 9, the anode plate 7 is respectively connected with the positive pole of the direct current power supply, the capsule cathode 8 is respectively connected with the negative pole of the direct current power supply, and the operation condition of the reactor can be controlled by adjusting the current, the electrifying time and the number of electrode pairs.

Referring to FIG. 3, the front inlet of the device is connected with an electrolyte tank 11 and a peristaltic pump 12, and the rear outlet is connected with H₂O₂Storage tank or H₂O₂By means of the device 13. Continuous operation of the apparatus and H can be achieved by continuous supply of electrolyte to the apparatus 10 by means of the peristaltic pump 12₂O₂The real-time collection and utilization of the H can be realized by controlling the flow rate of the peristaltic pump₂O₂And (5) regulating and controlling the yield.

It should be understood that the embodiments discussed herein are for illustrative purposes only and that modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the purview of the appended claims.

Claims

1. Continuous flow gallery type H based on plug-in capsule cathode₂O₂The synthesis reactor is characterized in that a plug-in capsule cathode is adopted, anode plates are staggered to form galleries, continuous flow liquid inlet is adopted, and H is generated₂O₂Is continuously accumulated with the electrolyte flow in the gallery and is collected at the end.

2. The pluggable capsule cathode-based continuous flow gallery type H of claim 1₂O₂The synthesis reactor is characterized in that the pluggable capsule cathode adopts a cylindrical air diffusion cathode made of carbon black-graphite-PTFE, a catalyst layer and a gas diffusion layer are respectively rolled to two sides of a stainless steel net and then rolled into a cylinder to form an inner cavity, the gas diffusion layer is arranged on the inner side of the cylinder, and the catalyst layer is arranged on the outer side of the cylinder.

3. The pluggable capsule cathode-based continuous flow gallery type H of claim 2₂O₂Synthesis reactor ofIs characterized in that the connection part of the side edge of the winding drum is bonded and fixed through a specially-made long I-shaped clamp, the bottom of the winding drum is sealed by a seal head, and the capsule electrode is integrated into a whole and can be directly plugged and pulled for use.

4. The pluggable capsule cathode-based continuous flow gallery type H of claim 1₂O₂The synthesis reactor is characterized in that the anode plate is fixed through clamping grooves on the side and the bottom of the reactor, and the material of the anode plate comprises but is not limited to noble metals, heavy metals, metal alloys and metal composite metal oxides.

5. The plug-in capsule cathode-based continuous flow gallery type H of claim 1₂O₂The synthesis reactor is characterized in that anode plates in the reactor are fixed in grooves on the side and the bottom of the reactor in a staggered manner to form galleries, the pluggable capsule cathode is fixed through a clamping groove on the bottom of the reactor, the inner side of a cylinder is in direct contact with air, the outer side of the cylinder is in contact with electrolyte, and capsule cathode rows and anode plates in the reactor are orderly and alternately arranged.

6. The plug-in capsule cathode-based continuous flow gallery type H of claim 1₂O₂The synthesis reactor is characterized in that liquid is continuously fed from one side of the reactor, electrolyte flows to the other side along galleries formed by the staggered anode plates and collects H generated in the process₂O₂And collected on the other side of the reactor.

7. The pluggable capsule cathode-based continuous flow gallery type H of claim 1₂O₂The synthesis reactor is characterized in that a plurality of anode plates are respectively connected to the positive pole of a direct current power supply, and a plurality of plug-in capsule cathodes are respectively connected to the negative pole of the direct current power supply.