Reactor for liquid-solid phase photocatalysis carbon dioxide reduction

Abstract

The utility model discloses a liquid-solid phase photocatalytic carbon dioxide reduction reactor, and belongs to the technical field of photocatalysis. The reactor comprises a quartz reactor, an aeration device, a gas circulation device and a gas supply device. The quartz reactor part comprises a CO2 gas inlet, an extraction opening of the circulating device, a pressure gauge, a gas product sampling opening, a liquid product sampling opening, a vacuum opening and magnetons. The aeration device is a one-circle or multi-circle aeration pipeline formed by a polytetrafluoroethylene pipe with fine and porous holes, and is used for forming compact and fine bubbles from reaction gas and blowing the bubbles into the reactor. And the gas circulating device comprises a three-way valve, a gas pipe of the circulating device and a micro gas pump. And the gas supply device comprises CO2 steel cylinder gas and a mass flow meter. According to the aeration, pressurization and circulation integrated reaction device, the solubility of carbon dioxide gas in water can be enhanced, so that the carbon dioxide gas is in full contact with a catalyst, and the mass transfer efficiency of reaction is improved, so that the performance of photocatalytic carbon dioxide reduction reaction is improved.

Description

Technical Field

[0001] This invention belongs to the field of photocatalysis technology, specifically relating to a reactor device for a liquid-solid phase photocatalytic carbon dioxide reduction reaction system, used to solve the problem of low mass transfer efficiency in liquid-solid phase systems. Background Technology

[0002] Photocatalytic CO2 reduction technology simulates the photosynthesis of plants in nature, using H2O as a reducing agent. Under light conditions, photogenerated electrons and holes are generated, and active species participate in the photocatalytic reaction. Under mild conditions, CO2 can be effectively reduced to carbon monoxide, methane and other products, thus realizing the utilization of solar energy. As a green and sustainable development approach, it has attracted much attention. Over the years, in order to improve photocatalytic activity and selectivity, researchers have not only designed and developed high-performance photocatalysts, but also actively constructed suitable catalytic reaction systems and optimized reactor designs. Photocatalytic CO2 reaction systems are mainly divided into gas-solid phase and liquid-solid phase. Compared with the gas-solid phase reaction system, the advantages of the liquid-solid phase system are mainly reflected in the following aspects: (1) In the liquid-solid phase system, the catalyst is uniformly dispersed in the solution. Continuous stirring can improve the charge transfer efficiency and photogenerated carrier separation efficiency, thereby improving the reaction activity; (2) In the liquid-solid phase system, the catalyst exists in the form of suspended particles, with a larger contact area with CO2 gas, which is conducive to the adsorption and activation of reactants on the catalyst surface; (3) It can Flexible addition of sacrificial agents to capture photogenerated holes, such as acetonitrile, triethylamine and isopropanol, to prevent photogenerated holes from recombinating with photogenerated electrons, thereby allowing a large number of electrons to participate in the CO2 reduction reaction; (4) Liquid-solid phase systems are usually carried out at room temperature and pressure, with mild reaction conditions, no need for high temperature and high pressure equipment, low energy consumption and in line with the concept of green chemistry; (5) In liquid-solid phase systems, gaseous products such as H2 and CO have low solubility in water and will overflow into the gas phase, while liquid products will dissolve in water, thus facilitating the separation and detection of products. Of course, liquid-solid phase also has disadvantages, such as the limited solubility and diffusion coefficient of CO2 in H2O (solubility < 0.033 mol·L at 25℃). -1 This will limit the mass transfer efficiency of the photocatalytic CO2 reduction reaction, thereby reducing the reaction rate. This problem can be solved by designing and optimizing the reactor. Utility Model Content

[0003] The present invention provides a novel liquid-solid phase photocatalytic carbon dioxide reduction reactor, which enhances the solubility of CO2 gas in water through an integrated aeration, pressurization and circulation design, allowing it to fully contact the catalyst, thereby improving the mass transfer efficiency of the reaction and enhancing the performance of the photocatalytic CO2 reduction reaction.

[0004] To achieve the above-mentioned objectives, this utility model is implemented through the following technical solutions.

[0005] This utility model relates to a liquid-solid phase photocatalytic carbon dioxide reduction reactor, which comprises a quartz reactor, an aeration device, a gas circulation device, and a gas supply device. The quartz reactor includes a CO2 inlet, a gas extraction port of the circulation device, a pressure gauge, a gas product sampling port, a liquid product sampling port, a vacuum port, and a magnetic inlet. The gas supply device includes CO2 cylinder gas and a mass flow meter.

[0006] Furthermore, the aeration device consists of one or more turns of polytetrafluoroethylene tubes with fine pores, used to blow the reaction gas into the reactor as dense, fine bubbles.

[0007] Furthermore, the gas circulation device includes a three-way valve, a gas pipe for the circulation device, and a miniature air pump.

[0008] Compared with the prior art, the present invention has the following technical effects:

[0009] 1. The concept of this utility model originates from water treatment aeration tanks and gas purification and circulation technology. This utility model adds an aeration device and a gas circulation device to a photocatalytic reactor to enhance the solubility of CO2 gas in water and improve the mass transfer efficiency of the reaction. It can effectively solve the problem of low mass transfer efficiency in liquid-solid phase photocatalytic CO2 reaction.

[0010] 2. The integrated aeration, pressurization, and circulation reactor proposed in this utility model can further promote the engineering application of photocatalytic CO2 reduction technology by optimizing reaction conditions and using multi-stage reactors, and provide new ideas and options for reactor design for CO2 treatment.

[0011] 3. This utility model uses a reactor made entirely of quartz material, which is beneficial for the transmission and utilization of light.

[0012] 4. This invention can also be used in other liquid-solid phase photocatalytic reaction systems, and has a wide range of applications. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the liquid-solid phase photocatalytic carbon dioxide reduction reactor device of this utility model.

[0014] In the diagram: 1. CO2 cylinder gas, 2. Mass flow meter, 3. CO2 inlet, 4. Three-way valve, 5. Gas pipe of the circulation device, 6. Miniature air pump of the circulation device, 7. Air extraction port of the circulation device, 8. Aeration device, 9. Pressure gauge, 10. Gas product sampling port, 11. Liquid product sampling port, 12. Vacuum port, 13. Magnetic magnet. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings.

[0016] like Figure 1 As shown, the reactor of this utility model consists of a quartz reactor, an aeration device, a gas circulation device, and a gas supply device. The quartz reactor includes a CO2 inlet 3 (for introducing the reaction gas), a suction port 7 of the circulation device (for a micro-pump to extract and circulate the gas above the liquid), a pressure gauge 9 (for displaying the internal pressure of the reactor), a gas product sampling port 10, a liquid product sampling port 11, a vacuum port 12 (for evacuating air from the reactor before the reaction), and a magnetic stirrer 13 (for stirring the reaction solution). The aeration device 8 is a polytetrafluoroethylene tube with fine, porous structure, forming one or more loops of aeration pipe, used to blow the reaction gas into the reactor as dense, fine bubbles. The gas circulation device includes a three-way valve 3 (for connecting the gas supply device and the gas circulation device), a gas pipe 5 of the circulation device (for gas circulation), and a micro-pump 6 (for recirculating the reaction gas above the liquid into the liquid-phase reaction system). The gas supply device includes a CO2 cylinder 1 and a mass flow meter 2 (for regulating the gas flow rate).

[0017] The reactor of this invention is made entirely of quartz, offering excellent light transmittance. The aeration device generates tiny, dense bubbles of carbon dioxide gas, which are then introduced into the solution. Once the reactor is saturated with reactant gas, a pressure gauge is used to adjust the pressure to maintain a certain micro-pressure. The circulation device recirculates any undissolved and unreacted carbon dioxide gas above the liquid, creating a continuous internal circulation. This integrated aeration, pressurization, and circulation reactor enhances the solubility of carbon dioxide gas in water, ensuring sufficient contact with the catalyst and improving the mass transfer efficiency of the reaction, thereby improving the performance of the photocatalytic carbon dioxide reduction reaction.

[0018] During the reaction test, the catalyst powder sample was first added to the solution (including deionized water and hole sacrificial agent) and ultrasonically dispersed to ensure uniform dispersion. Then, a vacuum was created using a vacuum pump to a pressure of 10–10. -1 After Pa, the gas flow rate is adjusted to 50–200 mL / min using a mass flow meter, and the reactor is filled with gas through an aeration device to create a micro-pressure environment of approximately 0.5–0.1 MPa (pressure gauge reading). After the reaction gas is introduced, a micro air pump is used to circulate the gas above the liquid back into the water through the aeration device. During this process, the magnetic stirrer continuously stirs the gas, thereby carrying out the photocatalytic reaction.

[0019] This specification provides an illustrative description of the present invention and its embodiments. This description is not restrictive, and the accompanying drawings show only one embodiment of the present invention; the actual structure is not limited to this. Therefore, if those skilled in the art, inspired by this description, design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A liquid-solid phase photocatalytic carbon dioxide reduction reactor, characterized in that, The reactor consists of a quartz reactor, an aeration device, a gas circulation device, and a gas supply device. The quartz reactor section includes a CO2 inlet (3), a circulation device exhaust port (7), a pressure gauge (9), a gas product sampling port (10), a liquid product sampling port (11), a vacuum port (12), and a magnetic particle (13); The gas supply device includes CO2 cylinder gas (1) and mass flow meter (2).

2. The liquid-solid phase photocatalytic carbon dioxide reduction reactor as described in claim 1, characterized in that, The aeration device (8) is a polytetrafluoroethylene tube with fine pores forming one or more aeration pipes, used to blow the reaction gas into the reactor as dense and fine bubbles.

3. The liquid-solid phase photocatalytic carbon dioxide reduction reactor as described in claim 1, characterized in that, The gas circulation device includes a three-way valve (4), a gas pipe (5) for the circulation device, and a micro air pump (6).

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