Preparation method of nanofiber membrane for treating photovoltaic aluminum profile sewage

Abstract

The invention relates to a preparation method of a nanofiber membrane for treating photovoltaic aluminum profile sewage. The preparation method comprises the following steps: S1, preparing dispersion liquid of a high polymer material; s2, adding a modifier to obtain a spinning solution; s3, adding the spinning solution into electrostatic spinning equipment, controlling the shortest distance between the spraying end of a nozzle array and a rotary cylindrical collector to be 10-12cm, the rotating speed of the rotary cylindrical collector to be 300-500rpm, the spraying flow speed of each channel to be 0.5-1.5 mL / h and the spinning voltage to be 15-20KV, collecting spinning fibers, and then drying to obtain the nanofiber membrane. By adopting the method, the production efficiency of the nanofiber membrane can be improved so as to meet the requirement of sewage treatment under the condition of large capacity, meanwhile, the thickness uniformity of the nanofiber membrane is greater than or equal to 85%, the arrangement consistency is greater than or equal to 85%, and the nanofiber membrane has excellent sewage treatment capacity.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a method for preparing a nanofiber membrane for treating photovoltaic aluminum profile sewage. Background Art

[0002] Aluminum profiles are widely used in the photovoltaic industry. In order to improve the corrosion resistance, hardness, wear resistance and aesthetics of aluminum profiles, aluminum profiles are usually anodized to form an oxide film on the surface of aluminum and its alloys through electrochemical methods. The solution used in the anodizing process will become ineffective due to repeated use, thus generating a lot of waste liquid with high heavy metal content, which needs to be treated.

[0003] Electrospinning is a technology that stretches polymer solutions or melts into nanofibers through a high-voltage electric field. Compared with traditional methods, electrospinning can produce continuous fibers with diameters ranging from tens to hundreds of nanometers. However, the production efficiency of nanofiber membranes with smaller diameters is low. The demand for the use of nanofiber membranes in the field of sewage treatment is high, and the existing production capacity of nanofiber membranes is difficult to meet market demand.

[0004] In order to increase the yield of nano-scale electrospinning fiber membranes, multi-head spinning technology can be used to prepare multiple fibers at the same time, thereby significantly increasing the yield. An air supply system can also be added to the spinneret to use the combined effects of air flow stretching and electrostatic force stretching to improve the controllability and yield of nanofiber preparation. For example, patent application CN115627545A discloses an electrostatic spinning device and an electrostatic spinning nozzle control method thereof, wherein the spinning nozzle is controlled, the supply pump 32 is turned on, the spinning solution is extracted from the spinning solution box 33 and introduced into the coil, and then filled into the spinneret 312 from the coil, and the spinning solution is ejected from the spinneret hole of the spinneret at the bottom of the spinneret 312. At the same time, the supply pump 32 is turned on, and air is filled into the sleeve 311 arranged outside the spinneret 312, and finally ejected from the air outlet 313 at the bottom of the sleeve 311, and the fiber filaments are blown downward to avoid the entanglement of multiple fiber filaments. At the same time, the circuit of the high-voltage power supply electrode is energized, so that the spinning solution entering the spinneret 312 is electrostatically charged. At the same time, the servo motor of the linear motor 23 is operated, and the control electronic 24 is displaced left and right on the linear motor 23, thereby driving the nozzle 31 to displace left and right above the collector 41. The collector 41 collects the nanofibers ejected from the nozzle 31 to form nanofibers. In the above scheme, since the nozzle 31 continuously moves left and right during the process of spraying the solution, the thickness of the membrane filaments at the two ends of the spinning membrane collected by the collector 41 is higher than the membrane filaments in the center of the collector, and the thickness of the membrane is uneven, resulting in unstable performance of the nanofiber membrane. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem of poor membrane uniformity caused by the existing nanofiber membrane in the process of improving production efficiency, and to provide a method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater. The spray flow rate of the nozzle array is controlled by a peristaltic pump, combined with the control of the speed, distance and voltage of the rotating cylindrical collector, thereby improving the thickness uniformity and arrangement consistency of the nanofiber membrane.

[0006] The specific plan is as follows:

[0007] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0008] S1, dispersing the polymer material into a solvent to obtain a dispersion;

[0009] S2, adding molybdenum carbide modifier to the dispersion, stirring evenly to obtain a spinning solution;

[0010] S3. Add the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, and a rotating cylindrical collector is arranged on the side opposite to the nozzle array, wherein the area of ​​the maximum cross section obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is larger than the area of ​​the plane enclosed by the nozzle array, and the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10-12 cm, the rotation speed of the rotating cylindrical collector is 300-500 rpm, the flow rate of each channel is 0.5-1.5 mL / h, the spinning voltage is 15-20 KV, and the spun fibers are collected and then dried to obtain a nanofiber membrane.

[0011] Further, the polymer material is at least one of polycaprolactone, polyglycolic acid, polylactic acid, chitosan-polylactic acid copolymer, and polylactic acid-glycolic acid copolymer;

[0012] The solvent is a mixed solution of dichloromethane and dimethylformamide, and the volume ratio of dichloromethane to dimethylformamide is 2-3:1.

[0013] Furthermore, the mass concentration of the dispersion is 1-12%, preferably 3-10%, and more preferably 5-8%.

[0014] Furthermore, after the mixture is stirred evenly in S2, a vacuum pump is used to remove bubbles in the solution, and the degassing time is 30-300 minutes to obtain the spinning solution.

[0015] Furthermore, the mass ratio of the added amount of molybdenum carbide to the polymer material in the dispersion is 15-20 parts by weight: 80-85 parts by weight.

[0016] Furthermore, the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is 10-12 cm, and the rotating speed of the rotating cylindrical collector is 300-500 rpm.

[0017] Furthermore, the flow rate of each channel is 0.5-1.5 mL / h, and the spinning voltage is 15-20 KV.

[0018] Furthermore, the drying is carried out at 50 to 80° C. for 12 to 24 hours.

[0019] The present invention also protects the nanofiber membrane prepared by the method for preparing the nanofiber membrane for treating photovoltaic aluminum profile wastewater. The nanofiber membrane has a thickness of 10 to 50 μm, a thickness uniformity of greater than or equal to 70%, and an arrangement consistency of greater than or equal to 80%.

[0020] The present invention also protects a photovoltaic aluminum profile sewage treatment device, comprising the nanofiber membrane.

[0021] Beneficial effects: In the preparation method of the nanofiber membrane for treating photovoltaic aluminum profile wastewater provided by the present invention, a nozzle matrix design is adopted, combined with a cylindrical collector, to achieve multi-channel simultaneous spinning, which can increase the fiber output per unit time, and the rotating collector improves the consistency of fiber arrangement, which is helpful to manufacture high-performance spun fiber membranes.

[0022] Furthermore, in the method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater provided by the present invention, the closest distance between the spray end of the nozzle array and the rotating cylindrical collector is controlled to be 10-12 cm, the rotation speed of the rotating cylindrical collector is 300-500 rpm, the flow rate of each channel is 0.5-1.5 mL / h, and the spinning voltage is 15-20 KV, thereby improving the thickness uniformity and arrangement consistency of the nanofiber membrane, so that the thickness uniformity of the product is greater than or equal to 85%, and the arrangement consistency is greater than or equal to 85%.

[0023] Furthermore, in the method for preparing the nanofiber membrane for treating photovoltaic aluminum profile wastewater provided by the present invention, the polymer material is modified with molybdenum carbide, which can improve the ability of the nanofiber membrane to remove metal ions in wastewater, especially nickel and tin in wastewater. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. In the examples, those without specifying specific techniques or conditions are carried out according to the techniques or conditions described in the literature in this area or according to the product specification. Those without specifying the manufacturer of reagents or instruments used are all conventional products that can be obtained commercially. In the following examples, if not clearly stated, "%" refers to weight percentage.

[0025] The test methods used below include:

[0026] Thickness uniformity: Turn on the Keyence LS-9000 film thickness gauge and fix the device sensor head on the measurement platform, making sure that the optical axis is perpendicular to the sample. Measure the thickness of the glass substrate without the film. Place the nanofiber membrane on the glass substrate, properly positioned on the measurement area, and start the thickness measurement mode. After using the multi-point scanning mode, export the thickness measurement results of the device to CSV format and open it in a table. Set the allowable deviation range δ = 5%, measure n points, and calculate the measurement value h i With average thickness The absolute value of the difference / the average thickness value. Determine how many points n there are i satisfy Thickness uniformity = n i / n×100%.

[0027] Arrangement consistency: Take a certain length of nanofiber membrane, flatten the fiber film and fix it on a 75mm*25mm*1mm glass slide. Use a Nikon ECLIPSE Ci POL polarizing microscope, use the transmission mode to observe, adjust the angle of the polarizer, and observe the changes in the orientation light intensity of the fiber until the image is clearly visible. Import the image into ImageJ software, extract the fiber outline in the image, define the direction with the largest number of fibers with consistent arrangement direction as the main direction angle, and calculate the direction angle and number of fibers. Use the orientation index to quantify the arrangement consistency: the ratio of the number of fibers within the main direction angle ±10° to the total number of fibers. The closer the orientation index is to 1, the higher the arrangement consistency. The formula is: orientation index = number of fibers within the range of ±10° of the main direction angle / total number of fibers in the image.

[0028] Example 1

[0029] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0030] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0031] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0032] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 300 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 15 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0033] Example 2

[0034] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0035] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0036] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0037] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2, the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 400 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 15 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0038] Example 3

[0039] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0040] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0041] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0042] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 500 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 15 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0043] Example 4

[0044] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0045] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0046] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0047] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 500 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 18 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0048] Example 5

[0049] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0050] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0051] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0052] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2, the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 500 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 20 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0053] Example 6

[0054] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0055] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0056] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0057] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 500 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 1.0 mL / h, the spinning voltage is 18 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0058] Example 7

[0059] A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater comprises the following steps:

[0060] S1, dispersing the polymer material polylactic acid into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 2:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 10%;

[0061] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 15:85, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0062] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 12 cm, the rotation speed of the rotating cylindrical collector is 500 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 1.0 mL / h, the spinning voltage is 18 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0063] Comparative Example 1

[0064] A comparative sample was prepared with reference to Example 4, except that no modifier was added to the dispersion, as follows:

[0065] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0066] S2. Use a vacuum pump to remove bubbles in the dispersion liquid, the degassing time is 30 minutes, and a spinning solution is obtained;

[0067] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 200 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 18 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0068] Comparative Example 2

[0069] The comparative sample was prepared with reference to Example 4, except that the rotating speed of the rotating cylindrical collector was lower, and specifically included the following steps:

[0070] S1, dispersing the polymer material polycaprolactone into a mixed solution of dichloromethane and dimethylformamide, wherein the volume ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion solution, wherein the mass concentration of the dispersion solution is 8%;

[0071] S2, adding molybdenum carbide modifier to the dispersion, the mass ratio of molybdenum carbide addition to the polymer material in the dispersion is 20:80, stirring evenly, and then using a vacuum pump to remove bubbles in the solution, the degassing time is 30min, to obtain a spinning solution;

[0072] S3, adding the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, adopting a 5×5 rectangular array, and the plane area of ​​the array is 64 cm 2 A rotating cylindrical collector with a diameter of 12 cm is set on the side opposite to the nozzle array. The maximum cross-sectional area obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is 114 cm 2 , the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10 cm, the rotation speed of the rotating cylindrical collector is 200 rpm, the flow rate of each channel of the multi-channel peristaltic pump is 0.5 mL / h, the spinning voltage is 18 KV, the spun fibers are collected, and then dried at 60°C for 24 hours to obtain a nanofiber membrane.

[0073] Performance Testing

[0074] The nanofiber membrane samples prepared in the examples and comparative examples were tested, and the results are shown in Table 1.

[0075] Table 1 Nanofiber membrane performance test results

[0076]

[0077]

[0078] As can be seen from Table 1, a higher rotation speed helps to generate a thinner and more uniform film, which is suitable for manufacturing ultra-thin nanofiber membranes. In Comparative Example 2, the film is thicker when the rotation speed is 200 rpm, resulting in a decrease in thickness uniformity and arrangement consistency. Moreover, the film thickness shows a decreasing trend with increasing rotation speed. High voltage may lead to thinner fibers. High-speed rotation and high voltage can improve the uniformity of the film and fiber arrangement, thereby improving thickness uniformity and arrangement consistency.

[0079] Simulated sewage treatment test

[0080] Simulated wastewater containing nickel and simulated wastewater containing tin were prepared respectively. The preparation methods were as follows: 28.5 g of stannous chloride was weighed and put into a 250 mL beaker, 200 mL of deionized water was added, and 1-2 drops of concentrated sulfuric acid were added, and the mixture was stirred thoroughly until dissolved. The pH was adjusted to 7 with 0.1 mol / L NaOH solution and 1 mol / L dilute sulfuric acid solution, and then poured into a 1 L volumetric flask and made up to 1 L for later use.

[0081] Weigh 112.1 g of nickel sulfate and put it into another 250 mL beaker. Add 300 mL of deionized water and stir to dissolve. Adjust the pH to 7 with 0.1 mol / L NaOH solution and 1 mol / L dilute sulfuric acid solution. Then put it into a 1 L volumetric flask and make up to 1 L for later use.

[0082] The nanofiber membrane was divided into two equal parts and loaded into filter bags respectively, which were placed in filter tanks. Then, the prepared simulated sewage was introduced into the filter tanks respectively (one filter tank treated one type of sewage). The adsorption treatment was carried out at room temperature for 10 hours, and then the metal ion concentration in the simulated sewage after treatment was detected, as shown in the table below.

[0083] Table 2 Sewage treatment results

[0084] sample Nickel content before treatment Tin content before treatment Nickel content after treatment Tin content after treatment Example 4 25g / L 15g / L 0.13g / L 0.11g / L Comparative Example 1 25g / L 15g / L 19.89g / L 11.55g / L

[0085] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0086] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0087] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater, characterized in that: The following steps are involved: S1, dispersing the polymer material into a solvent to obtain a dispersion; S2, adding molybdenum carbide modifier to the dispersion, stirring evenly to obtain a spinning solution; S3. Add the spinning solution into an electrospinning device, wherein the electrospinning device comprises a multi-channel peristaltic pump, wherein the multi-channel peristaltic pump is connected to a nozzle array, and a rotating cylindrical collector is arranged on the side opposite to the nozzle array, wherein the area of ​​the maximum cross section obtained by cutting the rotating cylindrical collector perpendicular to the bottom surface is larger than the area of ​​the plane enclosed by the nozzle array, and the closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is controlled to be 10-12 cm, the rotation speed of the rotating cylindrical collector is 300-500 rpm, the flow rate of each channel is 0.5-1.5 mL / h, the spinning voltage is 15-20 KV, and the spun fibers are collected and then dried to obtain a nanofiber membrane.

2. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claim 1, characterized in that: The polymer material is at least one of polycaprolactone, polyglycolic acid, polylactic acid, chitosan-polylactic acid copolymer, and polylactic acid-glycolic acid copolymer; The solvent is a mixed solution of dichloromethane and dimethylformamide, and the volume ratio of dichloromethane to dimethylformamide is 2-3:

1.

3. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claim 2, characterized in that: The mass concentration of the dispersion is 1-12%, preferably 3-10%, and more preferably 5-8%.

4. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claim 3, characterized in that: After stirring evenly in S2, a vacuum pump is used to remove bubbles in the solution, and the degassing time is 30-300 minutes to obtain the spinning solution.

5. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to any one of claims 1 to 4, characterized in that: The mass ratio of the added amount of molybdenum carbide to the polymer material in the dispersion is 15-20 parts by weight: 80-85 parts by weight.

6. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to any one of claims 1 to 4, characterized in that: The closest distance between the ejection end of the nozzle array and the rotating cylindrical collector is 10-12 cm, and the rotating speed of the rotating cylindrical collector is 300-500 rpm.

7. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claim 6, characterized in that: The flow rate of each channel is 0.5-1.5 mL / h, and the spinning voltage is 15-20 KV.

8. The method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claim 7, characterized in that: The drying is carried out at 50 to 80° C. for 12 to 24 hours.

9. The nanofiber membrane prepared by the method for preparing a nanofiber membrane for treating photovoltaic aluminum profile wastewater according to claims 1-8 is characterized in that: The thickness of the nanofiber membrane is 10-50 μm, the thickness uniformity is greater than or equal to 85%, and the arrangement consistency is greater than or equal to 85%.

10. A photovoltaic aluminum profile sewage treatment device, comprising the nanofiber membrane according to claim 9.

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