A photothermal catalytic reaction system based on gas-liquid flow phase control

Abstract

This invention discloses a photothermal catalytic reaction system based on gas-liquid flow phase control, comprising a heat-concentrating device, a light-concentrating device, a reaction device, a gas cylinder for storing reaction gas, and a liquid storage tank for storing reaction liquid. The heat-concentrating device includes a solar collector tube fixed on a first support and a reflector for concentrating sunlight onto the solar collector tube. The reaction device includes a reactor located inside the solar collector tube. The reactor's inlet is connected to a first pipe and a second pipe via a tee. A gas flow meter is installed on the first pipe and connected to the gas cylinder. A peristaltic pump is installed on the second pipe and connected to the liquid storage tank. The reactor's outlet is connected to a product collector via a third pipe. The light-concentrating device includes a second support, which includes a circular frame fitted around the solar collector tube. One end of the circular frame is fixed to a four-corner frame, and the ends of the four-corner frames are fixed with lenses for focusing sunlight, thereby improving the utilization rate of solar energy and the efficiency of the photothermal catalytic reaction.

Description

Technical Field

[0001] This invention belongs to the field of photothermal catalysis technology, specifically a photothermal catalytic reaction system based on gas-liquid mobile phase control. Background Technology

[0002] Photoinduced thermocatalysis is an energy-saving reaction technology for thermocatalysis with external heating compensation, which combines the advantages of thermochemistry and photocatalysis. Solar energy is a sustainable energy source, and photothermal catalytic reaction systems powered by solar energy can meet the needs of heterogeneous catalysis. It has broad application prospects in environmental purification, energy conversion, chemical synthesis and other fields. See [Elimian EA, Zhang M, Sun Y, et al. Harnessing solar energy towards synergistic photothermal catalytic oxidation of VOCs[J]. Solar RRL, 2023, 2300-238.].

[0003] Compared to gas-solid phase reactions, gas-solid-liquid reactions have higher mass transfer efficiency. The reaction rate and product selectivity can be controlled by adjusting the relative flow rate and reaction conditions of the gas and liquid phases. Gas-liquid flow reactors can be expanded laterally or vertically as needed to meet the needs of reactions of different scales. Therefore, as an important material carrier in the fields of chemical reactions and energy conversion, gas and liquid flow control technology is of great significance for improving reaction efficiency and energy utilization efficiency.

[0004] Combining gas-liquid flow with photothermal catalytic reaction can bring higher mass transfer efficiency and contact area, thereby realizing the regulation of reaction conditions and the regeneration and recycling of catalysts in the reactor. In addition, [Bian X, Zhao Y, Zhou C, et al. Minimizing Temperature Bias through Reliable Temperature Determination in Gas-Solid Photothermal Catalytic Reactions[J]. Angewandte Chemie International Edition, 2023: e202219340.] proposed using a flowing reaction system to replace the sealed reactor, which can provide a consistent and stable dynamic equilibrium state for photothermal performance testing experiments. However, the input of reactants in the existing photothermal reaction system is a fixed value, which cannot be continuously and flexibly controlled. The reaction system does not flow, which leads to the inability to renew reactants in time and increases the risk of over-reaction. See [Li X, Wang C, Tang J. Methane transformation by photocatalysis[J]. Nature Reviews Materials, 2022, 7[8]: 617-632.]

[0005] The photocatalytic flow reaction devices proposed in [Li Yajuan. An expandable flow tube photocatalytic reaction device: 202220367107.X[P]. 2023-02-10.], [Zhou Ying. A continuous flow conversion system coupled with solar concentrated photocatalysis and energy storage: 202210738553.1[P]. 2022-09-23.], and [Wang Feng. A photocatalytic reduction flow reaction device: 202123049922.6[P]. 2022-07-19.] mostly use the packed column method to fix the photocatalyst, or only use the gas phase or liquid phase as the flow phase. Such single-phase flow systems have problems such as a single reaction system, uneven distribution of reactant molecules in different phases, and insufficient mass transfer efficiency.

[0006] Currently, there are also two-phase flow reaction systems used for photocatalytic oxidation degradation, such as [Zhang Kailong. Cylindrical solenoid continuous flow photocatalytic oxidation degradation water treatment device, system and method: 202210031483.6 [P]. 2022-07-22.], but they do not fully consider the utilization of solar energy and lack devices for concentrating light and heat. In addition, there are also photothermal reactors that use quartz sleeves and lenses to concentrate light, such as [Guo Liejin. Solar photothermal coupled phase conversion carbon dioxide reduction catalytic reaction system and method: 202210575885.2 [P]. 2023-03-10.], but they require additional heating methods to complete the heating compensation, resulting in low utilization rate of sunlight by the catalyst. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a photothermal catalytic reaction system based on gas-liquid flow phase control, which can precisely control the flow rate and feed ratio of the reaction liquid and reaction gas, has good light and heat concentration effects, and improves the utilization rate of solar energy and the reaction efficiency of photothermal catalytic reaction.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] A photothermal catalytic reaction system based on gas-liquid mobile phase control includes a heat-concentrating device, a light-concentrating device, a reaction device, a gas cylinder for storing the reaction gas, and a storage tank for storing the reaction liquid.

[0010] The solar collector includes a solar collector tube fixedly mounted on a first support and a reflector for concentrating sunlight onto the solar collector tube.

[0011] The reaction device includes a reactor installed inside a solar collector tube. The reactor's inlet is connected to a first pipe and a second pipe via a tee. A gas flow meter is installed on the first pipe and connected to a gas cylinder. A peristaltic pump is installed on the second pipe and connected to a storage tank. The reactor's outlet is connected to a product collector via a third pipe.

[0012] The concentrating device includes a second support, which includes a circular frame that is sleeved on the outside of the solar collector tube. One end of the circular frame is fixedly connected to a four-corner frame, and the ends of the four-corner frame are fixedly installed with lenses for focusing sunlight.

[0013] Furthermore, the length of the solar collector tube is 300-600mm, and its inner diameter and outer diameter are 45-55mm and 55-70mm, respectively.

[0014] Furthermore, the reflector is a concave arc-shaped plate, and the reflector is an aluminum film with a length of 650-700mm and a width of 300-350mm.

[0015] Furthermore, a temperature sensor is installed inside the solar collector tube.

[0016] Furthermore, the reactor is wrapped with an insulation sleeve made of aramid, aluminum silicate or high silica cloth, and the insulation sleeve only covers the lower half of the reactor.

[0017] Furthermore, the reactor outlet is equipped with a temperature measuring instrument and a light intensity measuring instrument.

[0018] Furthermore, the reactor is installed inside the solar collector tube via a reactor support;

[0019] The height of the reactor support is half the height of the reactor, and the length of the reactor support is 360-460 mm.

[0020] Furthermore, the reactor is a quartz coil reactor with the inlet and outlet located on the same side;

[0021] The quartz coil reactor has a length of 350–450 mm, a spiral number of 20–60, a spiral diameter of 20–60 mm, and an inner diameter and outer diameter of 3–7 mm and 7–12 mm, respectively, of its spiral channel.

[0022] Furthermore, the product collector is connected to the storage tank via a fourth pipe.

[0023] Furthermore, both the four-corner frame and the circular frame are made of aluminum alloy, and the distance between the four-corner frame and the circular frame is 700-1200mm.

[0024] Compared with the prior art, the present invention has the following technical effects:

[0025] This invention first achieves photothermal catalytic reaction in a mobile phase system by coordinating the feed ratio and flow rate of the reaction gas and liquid using a flow meter and a peristaltic pump. Secondly, a solid catalyst is pre-dispersed in the reaction liquid, enabling a gas-solid-liquid three-phase reaction in the reactor. Thirdly, sunlight is focused onto the reactor window using a lens, and the solar collector tube and reflector focus the solar energy 360° onto the reactor. This achieves excellent light and heat concentration while controlling the gas-liquid mobile phase, resulting in high solar energy utilization. No external heating is required for temperature compensation, thus improving the reaction efficiency of the photothermal catalytic reaction. Furthermore, the mobile phase system requires only a small amount of material, reducing over-reaction, increasing reaction efficiency, and facilitating the separation of products and reactants. The catalyst can be recycled. Moreover, the reaction system of this invention allows for the replacement of all three phases (gas, liquid, and solid), facilitating scale-up and multiphase reactions, adapting to different reactions, and offering high flexibility.

[0026] Compared with traditional photocatalytic reactors, the quartz coil reactor used in this invention has a significantly smaller diameter. Moreover, the outlet and inlet are located on the same side, which greatly increases the aspect ratio and improves the photon transmission efficiency. This ensures reaction efficiency while expanding the reaction scale. Attached Figure Description

[0027] Figure 1 : Flowchart of the photothermal catalytic reaction of the present invention;

[0028] Figure 2 : A schematic diagram of the structure of the heat-concentrating device, the light-concentrating device, and the reaction device of the present invention;

[0029] Figure 3 : A cross-sectional schematic diagram of the reaction device of the present invention;

[0030] Figure 4 : A schematic diagram of the structure of the second support of the present invention;

[0031] In the diagram: 1. Insulation sleeve; 2. Reactor; 3. Reactor support; 4. Solar collector tube; 5. Reflector; 6. First support; 7. Second support. Detailed Implementation

[0032] The specific content of the present invention will be further explained in detail below with reference to the embodiments.

[0033] like Figures 1-4 As shown, a photothermal catalytic reaction system based on gas-liquid flow phase control includes a heat-concentrating device, a light-concentrating device, a reaction device, a gas cylinder for storing the reaction gas, and a liquid storage tank for storing the reaction liquid. The reaction gas is CO2 or O2, and the reaction liquid includes a solvent and a catalyst uniformly dispersed therein. The solvent is H2O or glucose, and the concentration of the catalyst in the reaction liquid is 5-20 g / L.

[0034] The overall height of the solar collector device is 150-300mm. It includes a solar collector tube 4 fixedly mounted on the first support 6 and a reflector 5 for concentrating sunlight onto the solar collector tube 4. The reflector 5 is a concave arc-shaped plate that uses the focusing principle of the arc surface to concentrate sunlight 360° onto the solar collector tube 4. The reflector 5 has a length of 650-700mm and a width of 300-350mm when unfolded, and it is made of aluminum film. The solar collector tube 4 is equipped with a temperature sensor to record the internal temperature. The length of the solar collector tube 4 is 300-600mm, and its inner and outer diameters are 45-55mm and 55-70mm, respectively. It is used to convert sunlight into heat energy to provide the heat required for the reaction in the reaction device. The dimensions of the reflector 5 and the solar collector tube 4 affect their heat absorption area, thus affecting the solar collector effect.

[0035] The reaction device includes a reactor 2, which is installed inside a solar collector tube 4 via a reactor support 3. The height of the reactor support 3 is half the height of the reactor 2, providing sufficient light transmission area while supporting the reactor 2. The length of the reactor support 3 is 360-460 mm. The reactor 2 is a quartz coil reactor with its inlet and outlet on the same side. Compared to a quartz coil reactor with its inlet and outlet on opposite sides, this design extends the length of the reactor and increases the length-to-diameter ratio, resulting in more uniform material mixing. The length of the quartz coil reactor is 350-450 mm. The number of spiral turns in the quartz coil reactor is 20-60, and the spiral diameter is 20-60 mm. The inner and outer diameters of its spiral channel are 3-7 mm and 7-12 mm, respectively. The dimensions of the quartz coil reactor affect its tube length, volume, and specific surface area, thereby affecting the mass and heat transfer efficiency.

[0036] The reactor 2 is wrapped with an insulation sleeve 1 made of aramid, aluminum silicate or high silica cloth. The insulation sleeve 1 only wraps the lower half of the reactor 2, thereby ensuring heat and light concentration. The insulation sleeve 1 is used to keep the reactor 2 warm. The outlet of the reactor 2 is equipped with a temperature measuring instrument and a light intensity measuring instrument, which can record the reaction temperature and light intensity.

[0037] The concentrating device includes a second support 7 made of aluminum alloy. The second support 7 includes a circular frame with a diameter of 70-80mm that is sleeved on the outside of the solar collector tube 4. A four-corner frame is welded to one end of the circular frame. A lens for focusing sunlight is fixedly installed at the end of the four-corner frame, thereby forming a light spot to provide part of the reaction heat to the reactor 2. The lens is made of acrylic, quartz or glass and is a square lens with a side length of 520-1100mm. The distance between the four-corner frame and the circular frame is 700-1200mm. The distance between the lens and the reactor 2 can be controlled by adjusting the distance between the four-corner frame and the circular frame. The size of the four-corner frame needs to be determined according to the focal length of the lens so that the focal point of the lens falls on the window of the reactor 2 to achieve the best concentrating effect.

[0038] The feed inlet of reactor 2 is connected to a first pipe and a second pipe via a tee. A gas flow meter is installed on the first pipe and connected to a gas cylinder. A peristaltic pump is installed on the second pipe and connected to a storage tank. The discharge outlet of reactor 2 is connected to a product collector via a third pipe. The product collector is connected to the storage tank via a fourth pipe. Both the storage tank and the product collector are containers with three ports, each equipped with a valve. The storage tank has an independent chamber for storing gas. The first port of the storage tank is connected to the peristaltic pump via the second pipe, and the second port is connected to the product collector via the fourth pipe. The second port of the storage tank is connected to a gas bag for collecting exhaust gas. The two ports of the product collector are connected to the discharge outlet of reactor 2 and the storage tank via the third and fourth pipes, respectively. The catalyst and product flow into the storage tank with the liquid phase, realizing the recycling of the catalyst. During sampling and analysis, the product and catalyst need to be separated, and the exhaust gas is collected independently through the gas bag.

[0039] The gas flow meter controls the flow rate of the reactant gas to be between 5 and 20 mL / min. -1 The peristaltic pump controls the flow rate of the reaction solution at 5–30 mL / min. -1 ;

[0040] The first, second, and third pipes are all silicone hoses.

[0041] Application Example 1

[0042] Cu 0.04 In 0.25 ZnS y / PTPA carbon dioxide reduction reaction, reaction conditions are:

[0043] The reactant gas is CO2; the solvent of the reaction solution is H2O. To increase the dispersibility of the catalyst and prevent its precipitation in reactor 2, the catalyst powder is ball-milled for 0.5 h and then suspended in H2O; the flow rate of the reaction solution is 5 mL / min. -1 The reaction gas flow rate is 5 mL / min. -1 ;

[0044] The lens of the focusing device is a square lens with a side length of 520mm, made of acrylic. The diameter of the circular frame is 80mm, and the side length of the four corner frames is 796mm. The four corner frames are evenly welded to the circular frame.

[0045] The reflector 5 in the solar collector has an unfolded size of 650mm in length, 300mm in width, and 150mm in height, and is made of aluminum film; the solar collector tube 4 has an inner diameter of 45mm, an outer diameter of 55mm, and a length of 300mm.

[0046] The quartz coil reactor 2 of the reaction device has 20 spiral turns, a spiral diameter of 20 mm, an inner diameter of 3 mm, an outer diameter of 7 mm, and a total length of 350 mm. The inlet and outlet of the quartz coil reactor 2 are located on the same side. The insulation sleeve 1 is made of aramid material with a thickness of 3 mm. The height of the reactor support 3 is half the height of the reactor, and the length of the reactor support 3 is 360 mm. A temperature measuring instrument and a light intensity measuring instrument are installed at the outlet of the reactor 2 to record the reaction temperature and light intensity.

[0047] Under stirring, the reaction liquid is circulated out by a peristaltic pump and mixed with the reaction gas inside the silicone tubing before flowing into reactor 2 for photothermal catalytic reaction. At the outlet of reactor 2, the light intensity and temperature are detected and recorded in real time by a temperature measuring instrument and a light intensity measuring instrument, respectively. 2 mL of liquid product is collected every 0.5 h and analyzed by high performance liquid chromatography. The gaseous product collected in the gas bag is qualitatively and quantitatively analyzed by gas chromatography.

[0048] Application Example 2

[0049] The oxidation reaction of NiPS3 / PTDATA is carried out under the following conditions:

[0050] The reaction gas is O2, and the solvent of the reaction liquid is glucose. To increase the dispersibility of the catalyst and prevent its precipitation in reactor 2, the catalyst powder is ball-milled for 0.5 hours and then suspended in glucose. The flow rate of the reaction liquid is 15 mL / min. -1 The reaction gas flow rate is 15 mL / min. -1 ;

[0051] The lens of the focusing device is a square lens with a side length of 1100mm, made of acrylic. The diameter of the circular frame is 70mm, and the side length of the four corner frames is 1117mm. The four corner frames are evenly welded to the circular frame.

[0052] The overall height of the solar collector is 300mm, the unfolded dimensions of the reflector 5 are 700mm in length and 350mm in width, and the material is aluminum film; the inner diameter of the solar collector tube 4 is 55mm, the outer diameter is 70mm, and the length is 600mm.

[0053] The quartz coil reactor 2 of the reaction device has 20 spiral turns, a spiral diameter of 35 mm, an inner diameter of 5 mm, an outer diameter of 9 mm, and a total length of 400 mm. The inlet and outlet of the quartz coil reactor 2 are located on the same side. The insulation sleeve 1 is made of aluminum silicate material with a thickness of 5 mm. The height of the reactor support 3 is half the height of the reactor, and the length of the reactor support 3 is 450 mm. A temperature measuring instrument and a light intensity measuring instrument are installed at the outlet of the reactor 2 to record the reaction temperature and light intensity.

[0054] Under stirring, the reaction liquid is circulated out by a peristaltic pump and mixed with the reaction gas inside the silicone tubing before flowing into reactor 2 for photothermal catalytic reaction. At the outlet of reactor 2, the light intensity and temperature are detected and recorded in real time by a temperature measuring instrument and a light intensity measuring instrument, respectively. 2 mL of liquid product is collected every 0.5 h and analyzed by high performance liquid chromatography. The gaseous product collected in the gas bag is qualitatively and quantitatively analyzed by gas chromatography. The yields of the products in application example 1 and application example 2 are shown in Table 1.

[0055] Table 1: Yields of products in Application Examples 1 and 2

[0056]

Claims

1. A photo-thermal catalytic reaction system based on gas-liquid flow phase control, characterized in that, It includes a heat-concentrating device, a light-concentrating device, a reaction device, gas cylinders for storing reaction gases, and storage tanks for storing reaction liquids; The solar collector device includes a solar collector tube (4) fixedly installed on the first bracket (6) and a reflector (5) for concentrating sunlight onto the solar collector tube (4). A temperature sensor is provided inside the solar collector tube (4). The length of the solar collector tube (4) is 300~600 mm, and its inner diameter and outer diameter are 45~55 mm and 55~70 mm, respectively; The reflector (5) is a concave arc-shaped plate, and the reflector (5) is an aluminum film with a length of 650~700 mm and a width of 300~350 mm. The reaction device includes a reactor (2) installed inside the solar collector tube (4). The feed inlet of the reactor (2) is connected to a first pipe and a second pipe through a tee. A gas flow meter is installed on the first pipe and connected to a gas cylinder. A peristaltic pump is installed on the second pipe and connected to a liquid storage tank. The discharge outlet of the reactor (2) is connected to a product collector through a third pipe. A temperature measuring instrument and a light intensity measuring instrument are installed at the discharge outlet of the reactor (2). The concentrating device includes a second support (7), which includes a circular frame that is sleeved on the outside of the solar collector tube (4). One end of the circular frame is fixedly connected to a four-corner frame, and the ends of the four-corner frame are fixedly installed with lenses for focusing sunlight.

2. The photothermal catalytic reaction system based on gas-liquid mobile phase control according to claim 1, characterized in that, The reactor (2) is wrapped with an insulation sleeve (1) made of aramid, aluminum silicate or high silica cloth, and the insulation sleeve (1) only covers the lower half of the reactor (2).

3. The photo-thermal catalytic reaction system based on gas-liquid flow phase control according to claim 1, characterized in that, The reactor (2) is installed inside the solar collector tube (4) via a reactor support (3); The height of the reactor support (3) is half the height of the reactor (2), and the length of the reactor support (3) is 360~460mm.

4. The photothermal catalytic reaction system based on gas-liquid mobile phase control according to claim 3, characterized in that, The reactor (2) is a quartz coil reactor with the inlet and outlet located on the same side; The quartz coil reactor has a length of 350-450 mm, a spiral number of 20-60, a spiral diameter of 20-60 mm, and an inner diameter and outer diameter of 3-7 mm and 7-12 mm, respectively, of its spiral channel.

5. The photothermal catalytic reaction system based on gas-liquid mobile phase control according to claim 1, characterized in that, The product collector is connected to the storage tank via a fourth pipe.

6. The photo-thermal catalytic reaction system based on gas-liquid flow phase control according to claim 1, characterized in that, Both the four-corner frame and the circular frame are made of aluminum alloy, and the distance between the four-corner frame and the circular frame is 700~1200 mm.

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