A method and device for photocatalytic gas reaction by forced serpentine flow staggered hole arrangement

Abstract

The present application relates to the technical fields of photocatalytic gas reaction, in particular to a kind of forced serpentine flow staggered hole photocatalytic gas reaction method and device, method includes catalyst ladder arrangement, construct forced serpentine gas flow path, ladder light receiving and light energy distribution, gas step-by-step reaction and flow, process parameter adjustment and reaction determination, device includes reactor body, gas inlet, gas outlet, multiple inclined quartz sheet, through-hole, catalyst layer, reflector and micro blocking edge, multiple quartz sheets are arranged along the reactor axial spacing, quartz sheet edge is sealedly connected with the inner wall of reactor body, the through-hole on adjacent quartz sheet is staggered distribution, so that gas can only sequentially pass through each level through-hole and form serpentine flow path, light source is set on the upper portion of reactor body, reflector is set below, so that each level catalyst layer obtains ladder light receiving and reflection light supplementing.Can reduce gas short circuit flow and reaction dead zone, improve catalyst light receiving uniformity, mass transfer efficiency and photocatalytic reaction efficiency.

Description

Technical Field

[0001] This invention belongs to the field of photocatalytic gas reaction technology, and particularly relates to a photocatalytic gas reaction method and apparatus with forced serpentine flow and staggered apertures. Background Technology

[0002] Photocatalytic gas reactions utilize photocatalysts to excite electron-hole pairs under illumination, driving gas molecules to undergo redox reactions. Commonly used photocatalysts include TiO2, g-C3N4, and BiVO4. Commonly used light sources include ultraviolet light sources, visible light sources, and simulated sunlight sources. For gas-solid phase photocatalytic reactions, the reaction efficiency depends not only on the activity of the catalyst itself, but also on the light distribution in the reactor, the gas residence time, the contact mode between the gas and the catalyst layer, and whether there are short-circuit flows and dead zones in the reaction chamber.

[0003] Existing photocatalytic reactors typically lay the catalyst flat on a horizontal fixed bed, coat it on the tube wall, or load it onto the surface of internal packing. The gas to be treated enters from the inlet and flows freely along the reactor axis. While this structure can achieve basic contact between the gas and the catalyst, it still has the following problems: First, the light source direction is fixed. If the catalyst is arranged in multiple layers, the upper catalyst layer can easily block the lower catalyst layer, resulting in insufficient light intensity in the lower layer or the backlit area, and low light energy utilization. Second, the gas can easily short-circuit along the low-resistance path, and some catalyst layers become reaction dead zones, which cannot be fully flushed and utilized by the gas. Third, the light direction and gas flow direction lack coordinated design, making it difficult to ensure that each stage of catalyst is simultaneously in the best light-receiving state and the best gas flow mass transfer state. Fourth, reducing the channel size or increasing the packing density to improve contact efficiency can easily lead to a sharp increase in pressure drop and energy consumption.

[0004] To address the aforementioned issues, a search revealed a patent with publication number CN101385964A that discloses a tubular photocatalytic reactor. This reactor uses helical blades to support the photocatalyst, allowing gas or liquid to move along the blades and undergo photocatalytic treatment under ultraviolet light irradiation. While this approach increases the fluid's movement path within the reactor and enhances contact between the fluid and the catalyst through the helical blades, it primarily relies on continuous helical blades to create an extended path. It does not divide the reactor interior into multiple independent chambers connected sequentially by a single through-hole, nor does it use staggered through-holes on adjacent quartz plates to force the gas to alternately pass upwards or downwards through the catalyst layer surface in each chamber. Furthermore, it lacks a stepped light-receiving structure composed of multiple inclined carriers, failing to structurally reduce the obstruction of the subsequent catalyst layer by the preceding carriers. It also lacks a non-bypass sealed connection between the quartz plate edges and the reactor inner wall, and a reflector to recover transmitted light. Therefore, problems such as uneven light distribution, localized gas short-circuiting, insufficient catalyst utilization, and uncontrollable mass transfer paths within the reaction chamber persist.

[0005] Therefore, the technical problem to be solved by this invention is how to provide a photocatalytic gas reaction method and apparatus that can force gas to flow through each catalyst layer, avoid bypass short circuits, balance low pressure drop and high mass transfer, and enable multiple catalyst layers to obtain relatively uniform illumination.

[0006] In light of this, in-depth research into the aforementioned issues led to the creation of this case. Summary of the Invention

[0007] The purpose of this invention is to provide a photocatalytic gas reaction method and apparatus with forced serpentine flow and staggered perforations, in order to solve the problems of existing fixed light source direction, where if the catalyst is arranged in multiple layers, the upper catalyst layer can easily block the lower catalyst layer, resulting in insufficient light intensity in the lower layer or backlit area, low light energy utilization, gas can easily short-circuit along low resistance paths, some catalyst layers become reaction dead zones, and cannot be fully flushed and utilized by the gas, the lack of coordinated design between the light direction and the gas flow direction makes it difficult to ensure that each stage of catalyst is in a better light-receiving state and a better gas flow mass state at the same time, and fourthly, when the channel size is reduced or the packing density is increased in order to improve the contact efficiency, it is easy to cause a sharp increase in pressure drop and energy consumption.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method and apparatus for photocatalytic gas reaction with forced serpentine flow and staggered perforations, comprising the following steps:

[0009] S1. Catalyst stepped arrangement: The photocatalyst is dispersed on the surface of multiple independent carriers in the reactor. Each independent carrier is inclined relative to the direction of incident light, so that the incident light can irradiate the photocatalyst layer on the surface of the independent carrier and form a thin layer of catalyst on the independent carrier.

[0010] S2. Construct a forced serpentine airflow path, dividing the inside of the reactor into multiple sequentially connected chambers. Adjacent chambers are connected by staggered through-holes, allowing the gas to be treated to pass through the catalyst layer surface from top to bottom or from bottom to top in each chamber, forming a serpentine flow path.

[0011] S3, stepped light reception and light energy distribution: The light source is placed above the reactor so that it shines vertically downwards on multiple tilted independent carriers. By adjusting the tilt angle of the independent carriers, each catalyst layer can be directly illuminated.

[0012] S4. Gas staged reaction and outflow: The gas to be treated is introduced into the reactor inlet and flows through the first to nth catalyst layers in sequence. Photocatalytic reaction occurs at each catalyst layer. The gas after the reaction is discharged from the reactor outlet.

[0013] S5. Adjustment of process parameters: Adjust gas flow rate, light source intensity, reaction temperature, humidity and pressure according to reaction requirements to optimize reaction rate and product selectivity.

[0014] S6. Reaction Judgment: When the reaction gas is detected to have reached the target conversion rate or the set running time, the reaction is terminated and the product or purified gas is output; when the target conversion rate or the set running time is not reached, the process parameters are adjusted or the reaction time is extended, and the reaction continues to circulate.

[0015] Preferably, in step S1, the tilt angle of the independent carrier relative to the horizontal axis of the reactor or the direction of incident light is 10° to 60°, and the photocatalyst is spread flat on the surface of the independent carrier in a thin layer with a thickness of 0.5 mm to 3 mm. By setting the tilt angle, the catalyst layer can face the light source in a stepped manner, reducing the obstruction between the front and rear carriers and enabling the thin-layer catalyst to obtain higher light-receiving efficiency.

[0016] Preferably, in step S2, when the outlet orifice of the i-th stage chamber is located at the upper part of the chamber, the inlet orifice of the (i+1)-th stage chamber is located at the lower part of the chamber; or when the outlet orifice of the i-th stage chamber is located at the lower part of the chamber, the inlet orifice of the (i+1)-th stage chamber is located at the upper part of the chamber, allowing the gas to be treated to flow alternately upwards or downwards between adjacent chambers. By staggering the orifices, the gas cannot bypass the reactor along its axial direction in a straight line; instead, it must deflect within each stage chamber and pass through the catalyst layer surface.

[0017] Preferably, in step S3, multiple independent carriers are arranged at intervals along the reactor axis to form a stepped light-receiving structure, and adjacent independent carriers are staggered to reduce the light shading of the next independent carrier by the previous independent carrier. Through stepped light reception and staggered arrangement, each catalyst layer can obtain relatively uniform light, thereby improving the effective utilization rate of the catalyst in the entire reactor.

[0018] Preferably, in step S4, the gas to be treated is one of the following: a gas containing volatile organic compounds, a gas containing carbon dioxide, a gas containing nitrogen, or a gas containing sulfur; the photocatalyst is one of the following: TiO2, g-C3N4, or BiVO4; and the light source is one of the following: an ultraviolet light source, a visible light source, or a simulated solar light source. By matching the types of gas, catalyst, and light source, it can be applied to different scenarios such as organic waste gas degradation, carbon dioxide photocatalytic reduction, photocatalytic ammonia synthesis, and photocatalytic oxidation desulfurization.

[0019] A photocatalytic gas reaction device for implementing a forced serpentine flow staggered hole photocatalytic gas reaction method includes a reactor body, an inlet at one end of the reactor body, an outlet at the other end of the reactor body, a plurality of quartz plates arranged sequentially along the axial direction on the inner side of the reactor body, through holes opened on the quartz plates, a catalyst layer disposed on the surface of the quartz plates, a light source disposed above the reactor body, and a reflector disposed below the reactor body.

[0020] Multiple quartz plates are inclined relative to the horizontal axis of the reactor body, and the through holes on adjacent quartz plates are staggered vertically. The edges of the quartz plates are sealed to the inner wall of the reactor body, forming a non-bypass sealed flow channel inside the reactor body. This allows the gas entering from the inlet to pass through multiple through holes in sequence and form a serpentine flow path before being discharged from the outlet.

[0021] Preferably, the reactor body is a horizontal tubular structure, made of high-transmittance quartz material, with the inlet and outlet being set as standard gas connection connectors, and both ends of the reactor body sealed with O-rings or flanges. The use of high-transmittance quartz material allows light emitted from the light source to pass through the reactor body and enter the internal catalyst layer area, facilitating external light source irradiation and reaction observation.

[0022] Preferably, 3 to 10 quartz plates are provided, and the multiple quartz plates are arranged at intervals along the axial direction of the reactor body. The angle between the quartz plates and the horizontal axis of the reactor body is 10° to 60°. By setting multiple quartz plates, multi-stage chambers and multi-stage catalyst contact areas can be formed within a limited reactor length, thereby improving the gas step-by-step reaction effect.

[0023] Preferably, the aperture of the through hole is 1mm to 8mm, and one through hole is provided on each quartz plate. One through hole of an adjacent quartz plate is located near the top inner wall of the reactor body, and the other through hole is located near the bottom inner wall of the reactor body. By setting the aperture and vertical position of the through hole, the gas generates a backflow when flowing through the adjacent chambers, increasing turbulence and lateral mixing, and reducing the proportion of short-circuit flow.

[0024] Preferably, the upper surface of the quartz plate is provided with a micro-edge, the height of which is 0.5mm to 1mm. The catalyst layer is disposed within the area enclosed by the micro-edge. A reflector is disposed below the reactor body to reflect light transmitted through the reactor body back to the catalyst layer. A temperature control jacket is also disposed on the outside of the reactor body to control the reaction temperature inside the reactor body at room temperature to 300°C. The micro-edge restricts the area where the catalyst layer is laid, preventing powder or coating from flowing to the edge of the quartz plate. The reflector reflects light transmitted through the reactor body back to the catalyst layer area, improving light energy utilization efficiency.

[0025] It should be noted that the above-mentioned photocatalytic gas reaction device is the preferred physical carrier for realizing the method. The protection focus of this invention is the synergistic method principle of forced serpentine flow, staggered conduction, stepped light reception, and non-bypass sealing. Any gas-solid phase photocatalytic reaction structure that can form a forced serpentine flow of gas through multiple sequentially connected chambers, staggered through holes, or equivalent structures, and enable the catalyst layer to obtain stepped light reception, can be used to realize the method of this invention.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. This invention disperses the photocatalyst on the surface of multiple independently inclined carriers, forming a stepped light-receiving structure along the reactor axis. This allows incident light to directly irradiate the surfaces of multiple catalyst layers, reducing the shading of downstream carriers by upstream carriers. Compared to methods that concentrate the catalyst on a single tube wall or a single horizontal carrier surface, this invention increases the effective photocatalytic area, improves the uniformity of light reception in each catalyst layer, reduces the problem of local catalyst failure due to insufficient light, and significantly increases the light intensity received per unit mass of catalyst.

[0028] 2. This invention divides the interior of the reactor into multiple interconnected non-bypass chambers by setting staggered single through holes on adjacent quartz plates and sealing the edges of the quartz plates with the inner wall of the reactor body. This prevents the gas from passing through the reactor quickly in a straight direction, but forces it to flow alternately upward or downward in multiple chambers, forming a forced serpentine airflow path. This airflow path can prolong the gas residence time, increase the contact opportunity between the gas and the catalyst layer surface, eliminate short-circuit flow and reaction dead zones, and make the catalyst utilization rate close to the state of full participation in the reaction.

[0029] 3. This invention sets up a light source above the reactor body and a reflector below it, so that the light source shines vertically downwards on the catalyst layer on the inclined quartz plate. At the same time, some of the light that passes through the reactor body can be reflected back to the catalyst layer area by the reflector, achieving the synergistic effect of forward illumination and reflected supplementary light. Combined with the limitation of the catalyst layer by the micro baffle and the control of the reaction temperature by the temperature control jacket, it can improve the light energy utilization rate, catalyst stability and reaction process controllability.

[0030] 4. By adjusting the aperture of the through holes, the spacing between the quartz plates, the number of quartz plate levels, and the tilt angle, this invention can control the pressure drop of the reactor while ensuring sufficient contact between the gas and the catalyst. This avoids the problem of excessive flow resistance caused by traditional packed beds or microchannel structures in pursuit of high mass transfer. This method does not depend on a specific catalyst or a specific light source and can be applied to a variety of photocatalysts such as TiO2, g-C3N4, and BiVO4, as well as various light sources such as ultraviolet light, visible light, and simulated sunlight. It is suitable for laboratory research and modular scale-up applications. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the serpentine flow path of the photocatalytic gas reaction device of the present invention;

[0032] Figure 2 This is a top view schematic diagram of the single quartz sheet structure of the present invention;

[0033] Figure 3 This is a schematic diagram of the stepped light reception and reflection supplementary light of the present invention;

[0034] Figure 4 This is a flowchart of the photocatalytic gas reaction method with forced serpentine flow and staggered pores according to the present invention.

[0035] In the diagram: 1. Reactor body; 2. Inlet; 3. Outlet; 4. Quartz plate; 5. Through hole; 6. Catalyst layer; 7. Light source; 8. Reflector; 9. Miniature baffle. Detailed Implementation

[0036] The embodiments of the present invention are described below with reference to the accompanying drawings. These embodiments are only some embodiments of the present invention, and their equivalent variations are all within the scope of protection.

[0037] Please see Figure 1-4 This invention provides a technical solution: a forced serpentine flow staggered perforation photocatalytic gas reaction method and apparatus. The apparatus includes a reactor body 1, with an air inlet 2 at one end and an air outlet 3 at the other end. Multiple quartz plates 4 are arranged axially along the inner side of the reactor body 1. Through holes 5 are opened on the quartz plates 4. A catalyst layer 6 is provided on the surface of the quartz plates 4. A light source 7 is provided above the reactor body 1, and a reflector plate 8 is provided below the reactor body 1. A micro baffle 9 is provided on the upper surface of the quartz plates 4. The reactor body 1 is preferably a horizontal tubular structure made of high-transmittance quartz material. The air inlet 2 and the air outlet 3 are respectively set as standard gas line connectors to facilitate connection with external gas sources, mass flow meters, humidity control devices, sampling and detection devices, or exhaust gas treatment devices.

[0038] Furthermore, multiple quartz plates 4 are inclined relative to the horizontal axis of the reactor body 1, and the edges of the quartz plates 4 are sealed to the inner wall of the reactor body 1, so that two adjacent quartz plates 4 form relatively independent chambers, and there are no bypass gaps between the chambers that allow gas to bypass the edges of the quartz plates 4. The multiple quartz plates 4 are arranged at intervals along the axial direction of the reactor body 1, and the angle between the quartz plates 4 and the horizontal axis of the reactor body 1 is 10° to 60°, preferably 30° to 45°. Through this inclined arrangement, the catalyst layer 6 on the upper surface of the quartz plates 4 can face the light source 7, and the gas can make disturbed contact along the surface of the catalyst layer 6 when it flows back.

[0039] Furthermore, through holes 5 are formed on quartz plates 4. Preferably, only one through hole 5 is provided on each quartz plate 4. The through holes 5 on adjacent quartz plates 4 are staggered vertically. Specifically, when the through hole 5 of the first-stage quartz plate 4 is close to the top inner wall of the reactor body 1, the through hole 5 of the second-stage quartz plate 4 is close to the bottom inner wall of the reactor body 1. When the through hole 5 of the second-stage quartz plate 4 is close to the bottom, the through hole 5 of the third-stage quartz plate 4 is close to the top, and so on. Through this staggered hole arrangement, the gas to be treated, after entering from the inlet 2, cannot flow directly to the outlet 3 along the central axis of the reactor body 1, but must alternately flow upward or downward between adjacent chambers, thereby forming a forced serpentine airflow path.

[0040] Furthermore, there are 3 to 10 quartz plates 4, the pore diameter of the through holes 5 is 1 mm to 8 mm, and the thickness of the catalyst layer 6 is 0.5 mm to 3 mm. The catalyst layer 6 can be formed on the surface of the quartz plate 4 by coating, spraying, scraping, dripping, impregnation and drying or sintering. The photocatalyst can be one of TiO2, g-C3N4 or BiVO4, or a composite photocatalyst can be selected according to the target reaction. The catalyst layer 6 is spread on the upper surface of the quartz plate 4 in a thin layer state, which can reduce the light attenuation inside the catalyst layer and increase the effective reaction area.

[0041] Furthermore, such as Figure 2 As shown, a micro-edge 9 is provided on the upper surface of the quartz plate 4. The micro-edge 9 encloses the area for laying the catalyst layer 6. The height of the micro-edge 9 is 0.5mm to 1mm. By setting the micro-edge 9, the flow range of the slurry can be restricted during the catalyst coating process, preventing the catalyst layer 6 from overflowing to the edge of the quartz plate 4. During the gas reaction process, it can also reduce the risk of catalyst powder being carried out by the airflow or accumulating and clogging at the through hole 5.

[0042] Furthermore, such as Figure 3 As shown, the light source 7 is positioned above the reactor body 1. The light source 7 can be an ultraviolet light source, a visible light source, or a simulated sunlight light source. The light source 7 illuminates the catalyst layer 6 on multiple inclined quartz plates 4 downwards. The multiple quartz plates 4 form a stepped light-receiving structure along the reactor axis. Adjacent quartz plates 4 are staggered to reduce the shading of the upper-level quartz plates 4 on the lower-level quartz plates 4. The reflector plate 8 is positioned below the reactor body 1 to reflect the light transmitted through the reactor body 1 and the quartz plates 4 back to the catalyst layer 6 area, so that part of the lower catalyst layer or the backlit area can be supplemented with light, thereby improving the overall light energy utilization rate.

[0043] Furthermore, a temperature control jacket can be installed on the outside of the reactor body 1. The temperature control jacket is used to control the reaction temperature inside the reactor body 1 between room temperature and 300°C. The temperature control jacket can be connected to a constant temperature circulating water bath, oil bath, or electric heating temperature control device to maintain a stable temperature of the reactor body 1 under different gas-phase photocatalytic reaction conditions. The reactor body 1 can also be connected to an external humidity control device, pressure control valve, gas mass flow meter, and online detection device to adjust gas flow, humidity, pressure, and reaction residence time.

[0044] Furthermore, such as Figure 4 As shown, the photocatalytic gas reaction method includes catalyst stepped arrangement, construction of a forced serpentine airflow path, stepped light reception and light energy distribution, gas step-by-step reaction and outflow, process parameter adjustment, and reaction judgment. First, the photocatalyst is dispersed on the surface of multiple inclined quartz plates 4 to form a thin catalyst layer 6 with a thickness of 0.5 mm to 3 mm. Then, the reactor body 1 is divided into multiple sequentially connected chambers by staggered through-holes 5 on adjacent quartz plates 4, so that the gas to be treated forms a serpentine flow path between the chambers. Then, the catalyst layers 6 are irradiated from above the reactor body 1 by a light source 7, and the transmitted light is recovered and reflected by a reflector plate 8, so that each catalyst layer 6 receives relatively uniform illumination. Finally, the gas to be treated is introduced from the inlet 2, so that it flows through the catalyst layers 6 step by step and undergoes a photocatalytic reaction under illumination. After reaching the target conversion rate or the set operating time, the product or purified gas is discharged from the outlet 3.

[0045] Furthermore, in the specific reaction process, the gas to be treated can be one of the following: a gas containing volatile organic compounds, a gas containing carbon dioxide, a gas containing nitrogen, or a gas containing sulfur. When the gas to be treated is a gas containing volatile organic compounds, the catalyst layer 6 can be a TiO2-type photocatalyst, and the light source 7 can be an ultraviolet light source. The gas contacts the catalyst layer 6 step by step in a forced serpentine flow path and undergoes an oxidative degradation reaction. When the gas to be treated is a gas containing carbon dioxide, the catalyst layer 6 can be a g-C3N4, BiVO4, or a composite semiconductor photocatalyst, and the light source 7 can be a visible light source or a simulated solar light source for the photocatalytic reduction reaction of carbon dioxide. When the gas to be treated is a gas containing nitrogen or sulfur, the appropriate catalyst, light source, and temperature and humidity conditions can be selected according to the target requirements of photocatalytic ammonia synthesis or photocatalytic desulfurization.

[0046] Furthermore, during the reaction process, the gas flow rate, light source intensity, reaction temperature, humidity, and pressure process parameters can be adjusted according to the reaction requirements to optimize the reaction rate and product selectivity. When the reaction gas reaches the target conversion rate or the set running time is reached, the reaction ends and the product or purified gas is output. When the target conversion rate or the set running time is not reached, the process parameters are adjusted or the reaction time is extended, and the reaction continues to cycle. The target conversion rate can be obtained through online gas chromatography, infrared gas analyzer, VOC detector, or other gas detection devices.

[0047] Example:

[0048] Example 1: The method and apparatus of this invention are used to degrade gaseous toluene. A horizontal quartz reactor is used. The reactor body 1 has an inner diameter of 40 mm and a length of 240 mm. Six circular quartz plates 4 are installed inside, with a spacing of 30 mm between adjacent quartz plates 4. The inclination angle of the quartz plates 4 relative to the horizontal axis of the reactor body 1 is 30°. A through hole 5 is alternately opened 5 mm above or below the center of each quartz plate 4. The diameter of the through hole 5 is 3 mm. TiO2 (P25) catalyst is sprayed onto each quartz plate 4 with a catalyst loading of 0.5 g. The light source 7 is a 365 nm LED strip with a power of 50 W. Under vertical irradiation from above, air containing 100 ppm toluene is introduced into inlet 2 at a flow rate of 100 mL / min during the reaction. The reaction is carried out at room temperature. The gas passes sequentially through the upper through-hole of the first plate, the chamber between the first and second plates, and the lower through-hole of the second plate, and continues to flow step by step along the staggered through-hole path until it exits after passing through the sixth through-hole. Each time toluene passes through a quartz plate 4, it is oxidized and degraded under photocatalysis. After 60 minutes of continuous reaction, the toluene concentration at the outlet drops to below 5 ppm, and the degradation efficiency reaches 95%. Under the same total catalyst mass and the same irradiation conditions, the toluene degradation efficiency of a traditional horizontal non-porous plate reactor is 70%.

[0049] Example 2: Optimization of method parameters. Taking the effect of the tilt angle of the quartz plate on the reaction effect as an example, the tilt angle of the quartz plate 4 was set to 0°, 15°, 30°, 45° and 60° respectively. Other reaction conditions were the same as in Example 1. The test results showed that when the tilt angle of the quartz plate 4 was 0°, the horizontal arrangement caused the front plate to block the light of the rear plate, and the toluene degradation efficiency was 62%. When the tilt angle was 30°, the light exposure state of the catalyst layer 6 and the gas reflection contact effect were better, and the degradation efficiency reached 95%. When the tilt angle was 45°, the degradation efficiency was 93%. When the tilt angle was 60°, the degradation efficiency was 88%, but the pressure drop increased slightly. Therefore, the preferred tilt angle of the quartz plate 4 is 30° to 45°.

[0050] Working principle: First, during use, the operator disperses the selected photocatalyst onto the upper surface of multiple quartz plates 4 by coating, spraying, or scraping. Micro-edges 9 are used to limit the catalyst spreading range, ensuring the catalyst layer 6 is stably spread on the surface of the quartz plates 4 in a thin layer of 0.5mm to 3mm. Then, multiple quartz plates 4 are installed at intervals along the axial direction of the reactor body 1, with the quartz plates 4 tilted at 10° to 60° relative to the incident light direction. The through holes 5 on adjacent quartz plates 4 are staggered, located near the top and bottom inner walls of the reactor body 1, respectively. Simultaneously, the edges of the quartz plates 4 are... The edge of the quartz plate 4 is sealed to the inner wall of the reactor body 1, thereby dividing the interior of the reactor body 1 into multiple sequentially connected chambers without any edge bypass gaps. When the gas to be treated enters the reactor body 1 through the inlet 2, because the edge of the quartz plate 4 is sealed to the inner wall of the reactor body 1, the gas cannot pass through in a straight line along the axial direction of the tube, nor can it flow around the edge of the quartz plate 4. It can only pass through the through holes 5 on the first-stage quartz plate 4 sequentially into the next chamber, and then flow back up or down according to the opposite height position of the next through hole 5, thus forming a continuous serpentine flow path between the multiple chambers. The light source 7 shines downwards from above the reactor body 1. Multiple inclined quartz plates 4 form a stepped light-receiving structure, allowing each catalyst layer 6 to be directly illuminated. Some of the light passing through the reactor body 1 and the quartz plates 4 is reflected back to the catalyst layer 6 area by the lower reflector plate 8, thus compensating for insufficient illumination on the backlit or lower side. The gas to be treated is forced to approach and pass through the surface of the catalyst layer 6 multiple times during the serpentine return process. Each time it passes through a catalyst layer 6, a photocatalytic reaction occurs under the illumination. The reaction path is longer than that of a straight-through axial flow path, and the gas residence time is more sufficient. The gas reacts with the catalyst layer 6. With the increase in contact area and number of contacts, the gas flow rate, light source intensity, reaction temperature, humidity and pressure can be adjusted according to the target conversion rate, target product or purification requirements during the reaction process. When the online detection device determines that the reaction gas has reached the target conversion rate or the system has reached the set running time, the gas after the reaction is discharged from the outlet 3. When the target conversion rate is not reached, the process parameters are adjusted or the reaction time is extended to continue the cyclic reaction. This achieves the synergy of forced serpentine flow, stepped light reception, staggered hole arrangement, non-bypass sealing and multi-stage catalytic reaction, thereby improving the efficiency of photocatalytic gas reaction and the gas purification or conversion effect.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A photocatalytic gas reaction device, characterized in that, Includes the following steps: S1. Catalyst stepped arrangement: The photocatalyst is dispersed on the surface of multiple independent carriers in the reactor. Each independent carrier is inclined relative to the direction of incident light, so that the incident light can irradiate the photocatalyst layer on the surface of the independent carrier and form a thin layer of catalyst on the independent carrier. S2. Construct a forced serpentine airflow path, dividing the inside of the reactor into multiple sequentially connected chambers. Adjacent chambers are connected by staggered through-holes, allowing the gas to be treated to pass through the catalyst layer surface from top to bottom or from bottom to top in each chamber, forming a serpentine flow path. S3, stepped light reception and light energy distribution: The light source is placed above the reactor so that it shines vertically downwards on multiple tilted independent carriers. By adjusting the tilt angle of the independent carriers, each catalyst layer can be directly illuminated. S4. Gas staged reaction and outflow: The gas to be treated is introduced into the reactor inlet and flows through the first to nth catalyst layers in sequence. Photocatalytic reaction occurs at each catalyst layer. The gas after the reaction is discharged from the reactor outlet. S5. Adjustment of process parameters: Adjust gas flow rate, light source intensity, reaction temperature, humidity and pressure according to reaction requirements to optimize reaction rate and product selectivity. S6. Reaction Judgment: When the reaction gas is detected to have reached the target conversion rate or the set running time, the reaction is terminated and the product or purified gas is output. When the target conversion rate or the set running time is not reached, the process parameters are adjusted or the reaction time is extended, and the reaction continues to circulate.

2. The photocatalytic gas reaction method with forced serpentine flow and staggered apertures according to claim 1, characterized in that: In step S1, the tilt angle of the independent carrier relative to the horizontal axis of the reactor or the direction of incident light is 10° to 60°, and the photocatalyst is spread on the surface of the independent carrier in a thin layer with a thickness of 0.5 mm to 3 mm.

3. The photocatalytic gas reaction method with forced serpentine flow and staggered apertures according to claim 1, characterized in that: In step S2, when the outlet orifice of the i-th stage chamber is located at the upper part of the chamber, the inlet orifice of the (i+1)-th stage chamber is located at the lower part of the chamber, or when the outlet orifice of the i-th stage chamber is located at the lower part of the chamber, the inlet orifice of the (i+1)-th stage chamber is located at the upper part of the chamber, so that the gas to be treated flows alternately upward or downward between adjacent chambers.

4. The photocatalytic gas reaction method with forced serpentine flow and staggered apertures according to claim 1, characterized in that: In step S3, multiple independent carriers are arranged at intervals along the reactor axis to form a stepped light-receiving structure, and adjacent independent carriers are staggered to reduce the light shading of the next independent carrier by the previous independent carrier.

5. The photocatalytic gas reaction method with forced serpentine flow and staggered apertures according to claim 1, characterized in that: In step S4, the gas to be treated is one of the following: a gas containing volatile organic compounds, a gas containing carbon dioxide, a gas containing nitrogen, or a gas containing sulfur; the photocatalyst is one of the following: TiO2, g-C3N4, or BiVO4; and the light source is one of the following: an ultraviolet light source, a visible light source, or a simulated solar light source.

6. A photocatalytic gas reaction apparatus for implementing the forced serpentine flow staggered aperture photocatalytic gas reaction method according to any one of claims 1-5, comprising a reactor body (1), characterized in that: One end of the reactor body (1) is provided with an air inlet (2), and the other end of the reactor body (1) is provided with an air outlet (3). Multiple quartz plates (4) are arranged sequentially along the axial direction on the inner side of the reactor body (1). Through holes (5) are opened on the quartz plates (4). A catalyst layer (6) is provided on the surface of the quartz plates (4). A light source (7) is provided above the reactor body (1), and a reflector plate (8) is provided below the reactor body (1). Multiple quartz plates (4) are inclined relative to the horizontal axis of the reactor body (1). The through holes (5) on adjacent quartz plates (4) are staggered vertically. The edges of the quartz plates (4) are sealed to the inner wall of the reactor body (1), so that a non-bypass sealed flow channel is formed inside the reactor body (1). This allows the gas entering from the inlet (2) to pass through multiple through holes (5) in sequence and form a serpentine flow path before being discharged from the outlet (3).

7. The photocatalytic gas reaction device according to claim 6, characterized in that: The reactor body (1) is a horizontal tubular structure. The reactor body (1) is made of high-transmittance quartz material. The air inlet (2) and air outlet (3) are respectively set as standard gas connection connectors. The two ends of the reactor body (1) are sealed by O-rings or flanges.

8. The photocatalytic gas reaction device according to claim 6, characterized in that: The quartz plates (4) are provided in 3 to 10 pieces, and the multiple quartz plates (4) are arranged at intervals along the axial direction of the reactor body (1). The angle between the quartz plates (4) and the horizontal axis of the reactor body (1) is 10° to 60°.

9. A photocatalytic gas reaction device according to claim 6, characterized in that: The diameter of the through hole (5) is 1mm to 8mm. One through hole (5) is provided on each quartz plate (4). One through hole (5) of the adjacent quartz plates (4) is located near the top inner wall of the reactor body (1), and the other through hole (5) is located near the bottom inner wall of the reactor body (1).

10. A photocatalytic gas reaction device according to claim 6, characterized in that: The upper surface of the quartz plate (4) is provided with a micro-edge (9), the height of the micro-edge (9) is 0.5mm to 1mm, the catalyst layer (6) is provided in the area enclosed by the micro-edge (9), the reflector (8) is provided below the reactor body (1) to reflect the light transmitted through the reactor body (1) back to the catalyst layer (6), and a temperature control jacket is also provided on the outside of the reactor body (1) to control the reaction temperature inside the reactor body (1) at room temperature to 300℃.

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