Double-helix photocatalytic microreactor based on solar fluorescence collection effect

Abstract

The present invention provides a double-helix photocatalytic microreactor based on the solar fluorescent light-collecting effect. The microreactor comprises a transparent microreaction layer and a cover plate. The microreaction layer is provided with two microchannels, both of which are spiral channels. The outer spiral channel encloses the inner spiral channel, and the two spiral channels are not connected to each other. The tops of the spiral channels are sealed by a cover plate, and the cover plate is provided with an inlet and an outlet at the head and tail ends of the two spiral channels. The outer spiral channel is a fluorescent channel, which is fed with a flowing fluorescent solution; the inner spiral channel is a reaction channel, which is fed with a flowing reaction solution. The photocatalyst is loaded in the reaction channel. The microreactor utilizes the fluorescent solution to absorb sunlight, converting the portion of the sunlight spectrum that is not absorbed by the photocatalyst into a spectrum that is absorbable. This has the advantages of improving the efficiency of solar energy utilization, increasing the efficiency of the photocatalytic reaction, and ensuring reaction stability.

Description

Technical Field

[0001] The present invention relates to the field of photocatalytic microfluidic reactors, in particular to a double-helix photocatalytic microreactor based on solar fluorescent light collection effect. Background Art

[0002] The photocatalytic microreactor is a new device that combines photocatalytic technology with microreactor technology. Thanks to its large specific surface area, excellent mass transfer efficiency, and good safety performance, it has achieved rapid development in the field of photocatalysis.

[0003] In the microreactor, the photocatalyst is excited by light of the corresponding wavelength, and the catalytic reactants react.

[0004] In order to increase the utilization rate of light energy and improve the efficiency of photocatalysis, relevant scholars have conducted a lot of research: Zeng et al. used the porous framework material ZIF-8 to modify the photocatalyst TiO2 to broaden the absorption spectrum and improve light energy absorption; Sheng et al. developed the enlarged generation effect of the photocatalytic microreactor under the spiral coil structure; Li et al. explored the storage and conversion process of light energy in the microreactor with a double-layer membrane structure.

[0005] The aforementioned studies have promoted light absorption and improved reaction efficiency by modifying photocatalysts and optimizing reactor structures. However, these treatment methods also have problems such as complex preparation processes, high economic costs, limited light energy utilization, and insufficient reactor stability.

[0006] For example, in the invention patent with application number 201910161945.4 and invention name "Universal fluorescent fluid photochemical micro-reaction device and its 3D printing manufacturing method", transparent photosensitive resin and the powerful spatial construction capabilities of 3D printing are used to prepare a photochemical micro-reaction device with both light collection channels and reaction channels. The purpose is to transform the reactor structure by adjusting the light source matching and improve the reaction efficiency.

[0007] Among them, there are two sets of schemes designed in this invention patent. The first is to design two sets of light channels and one set of reaction channels, and the light channels are located at the upper and lower ends of the reaction channels respectively; the second is to design the reaction channel as a straight square tube, and the light channel as a spiral circular tube, which is wrapped around the outer circumference of the reaction channel.

[0008] However, both of these solutions are based on fluorescence-harvesting microreactor designs. That is, their light source relies on fluorescence, with the primary function of the external light source being to excite the fluorescent material. However, most applications of photocatalytic microreactors are conducted under sunlight, which is subject to limitations in terms of natural angles and intensity, leading to instability in their applications.

[0009] If the invention uses sunlight as the light source, in the first structure, the two sets of light channels are located on the upper and lower sides of the reaction channel, blocking the direct exposure between the reaction channel and the sunlight, and reducing the utilization efficiency of the sunlight; in the second structure, the spiral circular tube can fully illuminate the reaction channel, but the spiral circular tube will still block part of the sunlight. The spiral circular tube is wrapped around the outside of the reaction channel, and the fluorescent substances in the two adjacent sections of the circular tube may also undergo fluorescence self-absorption due to mutual exposure, resulting in a weakening of the fluorescence intensity.

[0010] In addition, since the above-mentioned light channel is closed after the injection of fluorescence, and the intensity of sunlight changes continuously throughout the day, the fluorescence intensity changes uncontrollably, making it impossible to maintain the stability of the reactor.

[0011] Therefore, although the reactor structure designed in this invention has a fluorescent light-collecting effect, it is not suitable for use in a sunlight environment.

[0012] Based on the above reasons, technical personnel in this field urgently need to design a photocatalytic microreactor with a new structure, which can take into account the utilization efficiency of sunlight and fluorescence, and improve the photocatalytic efficiency and reaction stability. Summary of the Invention

[0013] The purpose of the present invention is to provide a double-helix photocatalytic microreactor based on the solar fluorescence light collection effect, which fully utilizes solar energy, increases the efficiency of photocatalytic reaction, and ensures the stability of the reactor, in order to address the shortcomings of the existing technology.

[0014] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a double-helix photocatalytic microreactor based on the solar fluorescent light-collecting effect, comprising a micro-reaction layer and a cover plate made of transparent material, wherein two microchannels are arranged on the micro-reaction layer, and both microchannels are spiral channels. The outer spiral channel wraps the inner spiral channel, and the two spiral channels are not connected to each other; the top of the spiral channel is closed by a cover plate, and the cover plate is respectively provided with an inlet and an outlet at the head and tail ends corresponding to the two spiral channels; the spiral channel located on the outer side is a fluorescent channel, into which a flowing fluorescent solution is introduced; the spiral channel on the inner side is a reaction channel, into which a flowing reaction solution is introduced, and the photocatalyst is loaded in the reaction channel.

[0015] Based on the above, the inlet and outlet of the fluorescent channel are externally connected to a fluorescent solution circulation control device, and the fluorescent solution circulation control device is externally connected to a sunlight sensor. According to the light intensity sensed by the sunlight sensor, the fluorescent solution circulation control device controls and changes the type, concentration and flow of the fluorescent solution.

[0016] Based on the above, the photocatalyst is loaded in the reaction channel by impregnation or physical or chemical deposition.

[0017] Based on the above, the cross-sectional shapes of the fluorescent channel and the reaction channel are both rectangular.

[0018] Based on the above, the fluorescence channel and the reaction channel have a channel width of 0.1 mm to 2 mm and a depth of 0.1 mm to 2 mm.

[0019] Based on the above, the distance between the fluorescence channel and the reaction channel is 0.5 mm to 2 mm.

[0020] Based on the above, the cover plate and the micro-reaction layer are bonded together.

[0021] Based on the above, the emission wavelength of the fluorescent solution matches the absorption wavelength of the photocatalyst.

[0022] Based on the above, the micro-reaction layer and the cover plate are made of high-transmittance glass or organic glass.

[0023] The present invention has outstanding substantial features and significant progress compared to the prior art. Specifically, the present invention has the following advantages:

[0024] 1. By utilizing the design of the double helix structure, the reaction solution in the reaction channel can not only be excited by the front solar light to promote the conversion of the reactants, but also, because it is sandwiched by the fluorescent channels on both sides, the fluorescent solution is excited by sunlight to produce fluorescence that matches the wavelength required for the photocatalytic reaction. Under the irradiation of fluorescence on both sides, that is, the three sides of the reaction channel are illuminated, the light intensity is increased, and the conversion rate is improved.

[0025] 2. The design of the double helix structure can maximize the layout of the dual-channel structure in a limited space, effectively extending the photocatalytic path of the reaction channel and further improving the conversion rate.

[0026] 3. The fluorescent solution is dynamically adjustable, especially the type, concentration and flow rate can be adjusted according to the light intensity, so that the reaction solution in the reaction channel receives relatively stable fluorescent light, thereby improving the stability of the microreactor.

[0027] 4. The reaction channel is loaded with photocatalysts, and with the help of transparent micro-reaction layers and cover plates, the photocatalytic efficiency is fully improved, further increasing the utilization rate of light.

[0028] 5. The cross-section of the spiral channel is designed to be a rectangular surface. The adjacent surfaces of the two spiral channels are parallel. The light introduction path will not be deflected, and the projection surface is concentrated and facing, which can improve the utilization efficiency of the fluorescent part.

[0029] 6. It can be widely used in environments with abundant natural resources of sunlight, especially in the fields of chemical industry, biology, detection, etc., and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the double-helix photocatalytic microreactor based on the solar fluorescence light collection effect in the present invention.

[0031] Figure 2 It is a structural schematic diagram of the cover plate in the present invention.

[0032] Figure 3 It is a structural schematic diagram of the micro-reaction layer in the present invention.

[0033] In the figure: 1. micro-reaction layer; 2. cover plate; 3. fluorescence channel; 4. reaction channel; 3a. fluorescence solution inlet; 3b. fluorescence solution outlet; 4a. reaction solution inlet; 4b. reaction solution outlet. DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described in detail below through specific implementation methods.

[0035] like Figure 1 、 Figure 2 and Figure 3 As shown, a double-helix photocatalytic microreactor based on the solar fluorescent light-collecting effect includes a micro-reaction layer 1 and a cover plate 2 made of transparent material. The cover plate 2 and the micro-reaction layer 1 are bonded together to achieve a sealed connection after bonding. The material of the micro-reaction layer and the cover plate is high-transmittance glass or organic glass, which meets the light transmittance requirements and has good corrosion resistance and chemical stability.

[0036] Two microchannels are provided on the micro-reaction layer 1, both of which are spiral channels. The outer spiral channel wraps the inner spiral channel. The two spiral channels are not connected to each other, similar to the coiled form of mosquito coils. The main parts of the two spiral channels are parallel to each other, and the layout is different only at the two ends. The cross-section of the spiral channel is rectangular, the channel width is 0.1mm-2mm, the depth is 0.1mm-2mm, and the channel spacing is 0.5mm-2mm.

[0037] The top of the spiral channel is closed by a cover plate 2, and the cover plate 2 is respectively provided with an inlet and an outlet at the head and tail ends of the two spiral channels, including a fluorescent solution inlet 3a, a fluorescent solution outlet 3b, a reaction solution inlet 4a, and a reaction solution outlet 4b in sequence; the spiral channel located on the outside is the fluorescent channel 3, into which the flowing fluorescent solution flows; the spiral channel on the inside is the reaction channel 4, into which the flowing reaction solution flows.

[0038] The fluorescent solution inlet 3a and the fluorescent solution outlet 3b of the fluorescent channel 3 are externally connected to a fluorescent solution circulation control device, and the fluorescent solution circulation control device is externally connected to a sunlight sensor. According to the light intensity sensed by the sunlight sensor, the fluorescent solution circulation control device controls and changes the type, concentration and flow of the fluorescent solution, wherein the emission wavelength of the fluorescent solution matches the absorption wavelength of the photocatalyst.

[0039] The photocatalyst is loaded in the reaction channel by impregnation or physical or chemical deposition.

[0040] Working principle:

[0041] A flowing reaction solution is introduced into the reaction channel 4, and a flowing fluorescent solution is introduced into the fluorescent channel 3. The microreactor is set to operate under a natural light environment.

[0042] The reaction solution in the reaction channel is illuminated from three sides, with the top being directly illuminated by sunlight. The two sides of the reaction channel are always sandwiched by the fluorescent channel 3. The fluorescent solution is excited by sunlight to produce fluorescence that matches the wavelength required by the photocatalyst, irradiating the reaction channel from the left and right sides.

[0043] The photocatalyst loaded in the reaction channel makes use of multiple irradiation of sunlight and fluorescent light to enable the photocatalytic reaction of the reaction solution in the reaction channel to occur efficiently, and the utilization efficiency of light energy is greatly improved.

[0044] Since natural light sources rise in the east and set in the west, the light intensity changes with time and weather. Through real-time sensing of the light intensity sensor, the type, concentration and flow rate of the fluorescent solution can be adjusted in time. That is, when sunlight is weak, the fluorescent light intensity can be increased by increasing the concentration of the fluorescent solution or slowing down the flow rate, thereby ensuring that the total light intensity received by the substances in the reaction channel remains unchanged, thereby improving the stability of the reactor.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and not to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention. They should all be included in the scope of the technical solution for protection of the present invention.

Claims

1. A double-helix photocatalytic microreactor based on the solar fluorescence light collection effect, characterized by: The device comprises a micro-reaction layer and a cover plate made of a transparent material. The micro-reaction layer is provided with two microchannels, both of which are spiral channels. The outer spiral channel wraps around the inner spiral channel, and the two spiral channels are not connected to each other. The tops of the spiral channels are closed by the cover plate, and the cover plate is provided with an inlet and an outlet at the head and tail ends of the two spiral channels respectively. The outer spiral channel is a fluorescent channel, into which a flowing fluorescent solution flows; the inner spiral channel is a reaction channel, into which a flowing reaction solution flows, and a photocatalyst is loaded in the reaction channel. The reaction solution in the reaction channel is illuminated from three sides, with the top being directly illuminated by sunlight. The two sides of the reaction channel are always sandwiched by fluorescent channels. The fluorescent solution is excited by sunlight to produce fluorescence that matches the wavelength required by the photocatalyst, irradiating the reaction channel from the left and right sides.

2. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 1, characterized in that: The inlet and outlet of the fluorescent channel are externally connected to a fluorescent solution circulation control device, and the fluorescent solution circulation control device is externally connected to a sunlight sensor. According to the light intensity sensed by the sunlight sensor, the fluorescent solution circulation control device controls and changes the type, concentration and flow of the fluorescent solution.

3. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 1 or 2, characterized in that: The photocatalyst is loaded in the reaction channel by impregnation or physical or chemical deposition.

4. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 3, characterized in that: The cross-sectional shapes of the fluorescent channel and the reaction channel are both rectangular.

5. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 4, characterized in that: The fluorescence channel and the reaction channel have a channel width of 0.1 mm to 2 mm and a depth of 0.1 mm to 2 mm.

6. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 5, characterized in that: The distance between the fluorescence channel and the reaction channel is 0.5 mm to 2 mm.

7. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 6, characterized in that: The cover plate and the micro-reaction layer are bonded together.

8. The double-helix photocatalytic microreactor based on solar fluorescence light collection effect according to claim 1, 2, 4, 5 or 6, characterized in that: The emission wavelength of the fluorescent solution matches the absorption wavelength of the photocatalyst.

9. The double-helix photocatalytic microreactor based on solar fluorescent light collection effect according to claim 8, characterized in that: The micro-reaction layer and the cover plate are made of high-transmittance glass or organic glass.

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