A photocatalytic coupled piezoelectric effect membrane fuel cell system

Abstract

The present invention discloses a photocatalytically coupled piezoelectric effect membrane fuel cell system, comprising a degradation chamber, a sample feed chamber provided on both sides of the degradation chamber, a photocatalytic membrane material provided at the connection between the degradation chamber and the sample feed chamber, a water outlet pipe connected to the upper portion of one end of the sample feed chamber, a water inlet pipe installed on both sides of the sample feed chamber, an aeration stone provided at one end of the water inlet pipe, and a sample outlet pipe installed on the top of the degradation chamber. The present invention uses a membrane material with piezoelectric and photocatalytic properties as the two poles of the fuel cell, converting chemical and mechanical energy into electrical energy under illumination and aeration, forming a piezoelectrically coupled photocatalytic membrane fuel cell system. Through aeration vibration, the piezoelectric and photocatalytic effects synergistically purify wastewater. The refraction of the prismatic polyhedron increases the utilization rate of visible light, accelerating the separation of photogenerated electrons and holes, and the vacuum pump pressure increases the contact area between the photocatalyst loaded in the membrane and the pollutants, improving the wastewater purification efficiency.

Description

Technical Field

[0001] The present invention relates to the field of wastewater purification, and in particular to a photocatalytic coupled piezoelectric effect membrane fuel cell system. Background Art

[0002] With people's long-term exploration and practice, organic wastewater treatment technologies have developed in the fields of physics, chemistry, and biology. However, these technologies all have a common defect - low treatment efficiency; considering material recovery, energy consumption costs and reducing trace substances in the environment, membrane technology is considered to be a good separation and purification technology. Membrane technology has low energy consumption, high separation selectivity, does not require additional chemical reagents, and its hazards and secondary pollution to the environment can be strictly controlled. Photocatalytic fuel cells (PFC) are a more promising technology for decomposing organic pollutants and purifying wastewater than fuel cells and photoelectrochemical cells. PFC realizes the conversion of chemical energy in organic chemicals into electrical energy, and effectively uses semiconductor materials to improve the performance of pollutant degradation systems and power generation forms. At present, photocatalytic fuel cells use silver and platinum as cathode materials, which are relatively expensive and cannot be recycled for secondary use. The piezoelectric effect is mostly generated by ultrasound, which is not conducive to practical application. Aeration is a commonly used treatment unit in the wastewater purification process, which can generate a certain amount of mechanical energy, causing the charge carriers in the piezoelectric coupled photocatalytic material to migrate, thereby degrading pollutants. To this end, the present invention provides a photocatalytic coupled piezoelectric effect membrane fuel cell system, which uses piezoelectric and photocatalytic effects to synergistically purify wastewater. The photocatalytic-piezoelectric effect membrane has a filtering effect, which is beneficial to the separation and recovery of the catalyst, and increases the contact area between the catalyst and the pollutants, which can further improve the catalytic performance and pollutant degradation rate. Summary of the Invention

[0003] The purpose of the present invention is to provide a photocatalytic coupled piezoelectric effect membrane fuel cell system to address the defects of the prior art and solve the problems raised by the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a photocatalytic coupled piezoelectric effect membrane fuel cell system, comprising a degradation chamber, wherein sampling chambers are provided on both sides of the degradation chamber, and piezoelectric-photocatalytic membrane materials are provided at the connection between the degradation chamber and the sampling chamber. An outlet pipe is connected to the upper part of one end of the sampling chamber, water inlet pipes are installed on both sides of the sampling chamber, an aeration stone is provided at one end of the water inlet pipe, and an outlet pipe is installed on the top of the degradation chamber.

[0005] As a preferred technical solution of the present invention, the sample outlet tube is connected to a vacuum pump.

[0006] As a preferred technical solution of the present invention, the piezoelectric-photocatalytic film material is fixed on both ends of the degradation chamber by a clamping plate. A circular opening with a diameter of 6 cm is provided in the middle of the clamping plate. The piezoelectric-photocatalytic film material is clamped by the clamping plate. The clamping plate is made of a resin glass plate. The diameter of the piezoelectric-photocatalytic film material is 10 cm, and the excess part is connected to an external data acquisition system. The piezoelectric-photocatalytic film material has both piezoelectric and photocatalytic effects.

[0007] As a preferred technical solution of the present invention, one end of the piezoelectric-photocatalytic film material is connected to an external resistor and an anode material through carbon fiber.

[0008] As a preferred technical solution of the present invention, the edges of the sandwich plate and both ends of the degradation chamber are sealed with sealant and fixed with screws.

[0009] As a preferred technical solution of the present invention, annular buckles are provided at the tube openings of the degradation chamber and the injection chamber, and the degradation chamber and the injection chamber adopt a hexagonal prism shape to increase the refraction and utilization rate of light.

[0010] As a preferred technical solution of the present invention, the aeration stones are installed on the front and back sides of the bottom of the sampling chamber and are fixed by a hose.

[0011] The beneficial effects of the present invention are as follows: the present invention uses a membrane material with piezoelectric and photocatalytic properties as the two poles of the fuel cell, forming a piezoelectric coupled photocatalytic membrane fuel cell system, which converts chemical energy and mechanical energy into electrical energy under illumination and aeration; when there is no illumination, the mechanical energy generated by aeration vibration and the built-in electric field between the heterojunctions are used to regulate the separation of electrons and holes, thereby achieving wastewater purification, and aeration is a commonly used facility in the wastewater purification process, without the need for additional energy consumption. When there is illumination, the piezoelectric effect can also improve the photocatalytic efficiency, and the two have a synergistic effect, which accelerates the spatial separation of semiconductor surface charges by regulating the charge transfer pathway, thereby achieving all-weather wastewater purification. The refraction of the prismatic polyhedron improves the utilization rate of visible light, accelerates the separation of electrons and holes, and the filtering effect of the membrane increases the contact area between the catalyst and the pollutant, improves the degradation rate of the pollutant, and synergistically purifies the wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A three-dimensional diagram of the photocatalytic coupled piezoelectric effect membrane fuel cell of the present invention;

[0013] In the figure: 1 carbon fiber; 2 water outlet pipe; 3 sample inlet chamber; 4 piezoelectric-photocatalytic membrane material; 5 aeration stone; 6 water inlet pipe; 7 screw; 8 degradation chamber.

[0014] Figure 2 This is a cross-sectional view of a photocatalytically coupled piezoelectric effect membrane fuel cell according to the present invention;

[0015] In the figure: 1 carbon fiber; 2 water outlet pipe; 4 piezoelectric-photocatalytic membrane material; 5 aeration stone; 6 water inlet pipe; 7 screw.

[0016] Figure 3 This is a graph showing the effect of the thickness of the piezoelectric-photocatalytic material film on the degradation rate of pollutants;

[0017] The horizontal axis represents time (in minutes), and the vertical axis represents concentration. The squares, dots, and regular triangles represent the degradation effects of photoelectrocatalytic membrane materials with thicknesses of 0.25 mm, 0.5 mm, and 0.75 mm, respectively, on pollutants in aqueous solution.

[0018] Figure 4 This is a diagram showing the effects of different external conditions on pollutant degradation rates in the present invention;

[0019] The horizontal axis represents time (in minutes), and the vertical axis represents concentration. The squares, dots, and regular triangles represent the degradation effects of the catalytic membrane material on aqueous solutions under illumination, aeration, and illumination plus aeration, respectively.

[0020] Figure 5 This is a diagram showing the effect of pH value on pollutant degradation rate in the present invention;

[0021] The horizontal axis represents time in minutes, and the vertical axis represents concentration; the square, dot, and equilateral triangle represent the degradation effect of the photoelectrocatalytic membrane material on pollutants under aeration and light conditions when the pH values are 3, 7, and 11, respectively.

[0022] Figure 6 This is a diagram showing the effect of pollutant degradation after adding a free radical scavenger to the present invention;

[0023] The horizontal axis represents time in minutes, and the vertical axis represents concentration; the square, dot, and equilateral triangle represent the degradation effect of the aqueous solution after light and aeration when the catalyst is added with 1 mL of ammonium oxalate (AO), benzoquinone (BQ), and tert-butyl alcohol (TBA) catalyst (all with a concentration of 1 mol / L). DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0025] Example: See Figure 1-2The present invention provides a technical solution: a photocatalytic coupled piezoelectric effect membrane fuel cell system, comprising a degradation chamber 8, a sampling chamber 3 is provided on both sides of the degradation chamber 8, a piezoelectric-photocatalytic membrane material 4 is provided at the connection between the degradation chamber 8 and the sampling chamber 3, an outlet pipe 2 is connected to the upper part of one end of the sampling chamber 3, a water inlet pipe 6 is installed on both sides of the sampling chamber 3, an aeration stone 5 is provided at one end of the water inlet pipe 6, and a sample outlet pipe is installed on the top of the degradation chamber 8.

[0026] The sample outlet tube is connected to the vacuum pump. The piezoelectric-photocatalytic film material 4 is fixed on both ends of the degradation chamber 8 through a clamping plate. A circular opening with a diameter of 6 cm is provided in the middle of the clamping plate. The piezoelectric-photocatalytic film material 4 is clamped by the clamping plate. The clamping plate is made of resin glass plate. The diameter of the piezoelectric-photocatalytic film material 4 is 10 cm. The excess part is connected to an external data acquisition system. The piezoelectric-photocatalytic film material 4 has both piezoelectric and photocatalytic effects.

[0027] One end of the piezoelectric-photocatalytic membrane material 4 is connected to an external resistor and anode material via carbon fiber 1. The edges of the membrane plate and degradation chamber 8 are sealed with sealant and secured with screws 7. Both the degradation chamber 8 and the injection chamber 3 are equipped with annular clips at their openings. Both chambers are hexagonal in shape to maximize light refraction and utilization. Aeration stones 5 are mounted on the front and rear sides of the bottom of the injection chamber 3 and secured with flexible hoses.

[0028] The system consists of three parts: the sampling chamber, the membrane plate, and the treatment chamber; there is one sampling chamber on each side, and the degradation chamber in the middle; the two pipe openings below the sampling chamber are connected to the aeration stone, and the water inlet pipe is on the left, through which the wastewater sample is injected into the container. The pipe outlet above the degradation chamber is the sample outlet pipe, which is connected to the vacuum pump; the membrane clamping plate is placed between the two chambers, and the inside of the plate is a circular opening with a diameter of 6 cm, which clamps the membrane with piezoelectric and photocatalytic properties. The membrane diameter is 10 cm, and the excess part is connected to an external voltmeter to detect current and voltage; the screws are tightened to ensure the sealing of the device. First, the contaminated wastewater is connected to the water inlet pipe and connected to the sample inlet chamber at a certain speed; after the wastewater comes into contact with the membrane with piezoelectric and photocatalytic properties, the aeration stone and xenon lamp are turned on for vibration light irradiation to stimulate the charge transfer to the surface of the semiconductor material to cause redox reaction, degrade the pollutants, and the membrane filters the ions in the water to purify the wastewater. Turn on the vacuum pump to extract the degraded water sample. The vacuum pump pressure simultaneously increases the contact area between the wastewater and the photocatalyst, accelerating the degradation reaction rate; degradation can still be carried out without light. The device realizes all-weather efficient degradation of pollutants and low-energy purification of wastewater.

[0029] The device is shaped like a hexagonal prism, which offers high stability. Side-light sources refract into the device, increasing visible light intensity. This allows for efficient pollutant degradation during the day, enabling continuous degradation around the clock. The membrane is composed of two 2mm-thick Plexiglas panels joined together, sealed at the edges with white rubber for a tight seal that prevents water leaks. A carbon fiber connection is attached to one end of the membrane, while the other end is connected to an external resistor and anode material. Panels can be added or removed based on experimental conditions for the polar material variables.

[0030] Materials with piezoelectric and catalytic properties can be: titanium dioxide, zinc oxide, carbon nitride, molybdenum disulfide, cadmium sulfide and other semiconductors. Photocatalytically excited electrons can not only react with dissolved O2 in the electrolyte to produce superoxide radicals (·O2 - ), after oxygen is exhausted, it can still react with hydrogen ions (H + ) reacts to generate H2, which is used to oxidize and degrade pollutants using free radicals.

[0031] Aeration stones are installed on the front and back sides of the bottom of the sampling chamber and fixed with hoses. According to experimental needs, the number of aeration stones is changed and the size of the flow meter is adjusted to control the air flow. The size is adjusted according to the experiment, and the aeration stones in the same group must be completely consistent.

[0032] The nozzles of the injection chamber and the degradation chamber are both equipped with annular buckles. Rotating the buckles adjusts the water flow and fixes the water pipes at the same time to avoid errors caused by insufficient airtightness of the experimental device. After the vacuum pump extracts the wastewater, it is input into the reflux device for storage and then flows into the water inlet pipe, thus repeatedly forming a circulating flow device, reducing the degradation steps and saving time.

[0033] The polluted wastewater that is degraded in the injection chamber includes the following substances: antibiotics such as tetracyclines, quinolones, sulfonamides, macrolides, and dyes such as rhodamine B, methylene blue, and methyl orange.

[0034] Implementation Case 1:

[0035] Preparation of the photoelectrocatalytic material MoS2 / ZnO: Weigh 0.72g of sodium molybdate dihydrate and 0.69g of thioacetamide powder, dissolve in 1-butyl-3-methylimidazolium chloride, slowly titrate with 60mL of 1mol / L hydrochloric acid, stir for 12 hours, place in a reactor, and react at 220°C for 24 hours. Rinse with anhydrous ethanol and deionized water, and dry at 60°C to obtain the desired MoS2. Mix 10mL of a 0.1M zinc acetate solution in ethanol and 20mL of a 0.5M sodium hydroxide solution in ethanol to form a transparent suspension. Add 0.2g of MoS2 and place in a reactor. React at 150°C for 24 hours, rinse several times with anhydrous ethanol, and dry at 60°C to obtain the desired MoS2 / ZnO composite material.

[0036] Add 50 mg of MoS2 / ZnO composite material powder to 9.5 mL of N-methylpyrrolidone, mix well, then add 0.5 g of PVDF particles, dissolve at a constant temperature of 80°C, add 0.2 mL of ammonia water, and stir on a stirrer for 6 h to form a dark gray solution. Scrape the film for use.

[0037] Investigate the effect of photocatalytic material film thickness on pollutant degradation rate: Use a dropper to draw the above MoS2 / ZnO photocatalytic material solution, adjust the scale of the film scraper, and make films with three thicknesses of 0.25mm, 0.5mm, and 0.75mm. Open the water inlet pipe to allow 20mg / L tetracycline hydrochloride solution to flow into the injection chamber. The MoS2 / ZnO film will undergo redox reaction after contacting with the tetracycline hydrochloride solution. Take a sample every 10 minutes for 7 times. Determine the absorbance by UV-visible spectrophotometry and calculate the removal rate. According to Figure 3 It can be seen that the degradation efficiency is best when the thickness is 0.5 mm.

[0038] Implementation Case 2:

[0039] Study the effect of photocatalytic conditions on the degradation rate of pollutants: a composite film with a thickness of 0.5 mm was selected and placed in the center of the sandwich panel. The MoS2 / ZnO film was reacted with a 20 mg / L tetracycline hydrochloride solution under the conditions of light, aeration, and aeration and light, and a sample was taken every 10 minutes for 7 times. Figure 4 The data obtained show that the optimal conditions are when aeration and lighting are carried out simultaneously.

[0040] Implementation Case 3:

[0041] To investigate the effect of pH on the degradation rate of pollutants: a composite membrane with a thickness of 0.5 mm was selected and placed in the center of the membrane board. Different pH values (3, 7, and 11) were changed under aeration and light conditions. The pH of the tetracycline hydrochloride solution was adjusted using concentrated hydrochloric acid and sodium hydroxide. The solution underwent redox reaction on the MoS2 / ZnO membrane and flowed into the outlet pipe of the degradation chamber under the action of a vacuum pump. A sample was taken every 10 minutes for 7 times. Figure 5 The data obtained showed that the optimum pH was 3.

[0042] Implementation Case 4:

[0043] To investigate the degradation rate of pollutants by free radical scavengers: a composite film with a thickness of 0.5 mm was selected and placed in the center of the sandwich plate. 1 mL of benzoquinone (BQ), ammonium oxalate (AO), and tert-butyl alcohol (TBA) (all at a concentration of 1 mol / L) were added under aeration and light conditions to capture O2 - , h +,·OH. The solution undergoes redox reaction on the MoS2 / ZnO membrane and flows into the outlet pipe of the degradation chamber under the action of the vacuum pump. A sample is taken every 10 minutes for 7 times. Figure 6 shown.

[0044] The present invention uses a membrane material with piezoelectric and photocatalytic properties as the two poles of the fuel cell, converting chemical energy and mechanical energy into electrical energy under light and aeration to form a piezoelectric coupled photocatalytic membrane fuel cell system. Through aeration vibration, the piezoelectric and photocatalytic effects synergistically purify wastewater; the refraction of the prismatic polyhedron increases the utilization rate of visible light and accelerates the separation of photogenerated electrons and holes, and the vacuum pump pressure increases the contact area between the photocatalyst loaded in the membrane and the pollutants, thereby improving the wastewater purification efficiency.

[0045] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A photocatalytic coupled piezoelectric effect membrane fuel cell system, comprising a degradation chamber (8), characterized in that: Both sides of the degradation chamber (8) are provided with a sampling chamber (3), the connection between the degradation chamber (8) and the sampling chamber (3) is provided with a piezoelectric-photocatalytic membrane material (4), the upper part of one end of the sampling chamber (3) is connected to a water outlet pipe (2), both sides of the sampling chamber (3) are provided with a water inlet pipe (6), one end of the water inlet pipe (6) is provided with an aeration stone (5), and the top of the degradation chamber (8) is provided with a sampling pipe; The piezoelectric-photocatalytic film material (4) serves as the two poles of a fuel cell; The piezoelectric-photocatalytic film material (4) is fixed to both ends of the degradation chamber (8) through a clamping plate, a circular opening with a diameter of 6 cm is provided in the middle of the clamping plate, and the piezoelectric-photocatalytic film material (4) is clamped by the clamping plate, the clamping plate is a resin glass plate, the diameter of the piezoelectric-photocatalytic film material (4) is 10 cm, and the excess part is connected to an external data acquisition system, and the piezoelectric-photocatalytic film material (4) has both piezoelectric and photocatalytic effects; The degradation chamber (8) and the sample injection chamber (3) are both provided with annular buckles at their pipe openings. The degradation chamber (8) and the sample injection chamber (3) are in the shape of hexagonal prisms to increase the refraction and utilization rate of light. The aeration stone (5) is installed on the front and rear sides of the bottom of the sample injection chamber (3) and is fixed by a hose. The sample outlet pipe is connected to a vacuum pump.

2. The photocatalytically coupled piezoelectric effect membrane fuel cell system according to claim 1, characterized in that: The edges of the membrane plate and the degradation chamber (8) at both ends are sealed with sealant and fixed with screws (7).

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