Preparation process of needle-free photovoltaic aluminum profile sewage treatment electrostatic spinning nanofiber membrane

Abstract

The invention relates to a preparation process of a needle-free electrostatic spinning nanofiber membrane for sewage treatment of a photovoltaic aluminum profile. The preparation process comprises the following steps: S1, dispersing a high polymer material into a solvent; s2, vanadium carbide is added for modification, and a spinning solution is obtained; s3, carrying out degassing treatment on the spinning solution; and S4, electrostatic spinning is conducted, electrostatic spinning equipment comprises a flow pump, the flow pump is connected with a porous nozzle plate, a parallel electrode collector is arranged on the side, away from the flow pump, of the porous nozzle plate, and the flow speed of the treatment liquid sprayed out of the porous nozzle plate is controlled to be 0.5 mL / h to 1.0 mL / h through the flow pump. The shortest distance between the porous nozzle plate and the parallel electrode collector is 10-12 cm, the electrode distance of the parallel electrode collector is 15-20 cm, the loading voltage is 20-30 KV, and the prepared electrostatic spinning fibers are dried to obtain the nanofiber membrane. According to the process, the blocking problem caused by spraying the spinning solution by a needle head can be avoided, the production efficiency is improved, and meanwhile, the strength and uniformity of the fiber membrane are improved.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic aluminum profile wastewater treatment, in particular to a preparation process of a needle-free photovoltaic aluminum profile wastewater treatment electrostatic spinning nanofiber membrane. Background Art

[0002] During the production process of photovoltaic aluminum profiles, wastewater containing various pollutants may be generated, including heavy metals, acid and alkali substances, organic solvents and other harmful substances. If these wastewaters are not properly treated, they will pose a serious threat to the environment and human health. The treatment technology for photovoltaic aluminum profile wastewater includes a combination of physical, chemical and biological methods. Among them, the physical method is to remove pollutants in wastewater by means of filtration, adsorption, precipitation, centrifugal separation, etc., which is widely used in industry.

[0003] The application of electrospun fiber membrane in sewage treatment is a field that has attracted much attention. Its unique structure and performance make it show great potential in sewage treatment. For example, polylactic acid fiber has an adsorption effect on metal nickel ions in photovoltaic aluminum profile sewage and can be used in photovoltaic aluminum profile sewage treatment.

[0004] Electrospinning fiber membrane uses high-voltage electrostatic field to eject polymer solution from a needle, forming nano-scale fibers on a flat collector. In order to obtain spinning fibers with a lower diameter, a finer needle is required, and the polymer solution usually has a certain viscosity, which can easily cause nozzle clogging, requiring the production process to be shut down for maintenance, and production efficiency cannot be improved. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem of low production efficiency caused by clogging and collision of electrospun nanofiber membranes in the existing photovoltaic aluminum profile wastewater treatment, and to provide a preparation process of needle-free photovoltaic aluminum profile wastewater treatment electrospun nanofiber membranes. A needle-free orifice plate is used as a channel for the outflow of the spinning solution, and a flow pump is combined to control the spray flow rate. A parallel electrode collector is used as a collecting device. The clogging rate of the system is zero, and the consistency of fiber arrangement is improved. The obtained nanofiber membrane has a higher tensile strength.

[0006] The specific plan is as follows:

[0007] A preparation process of a needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

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

[0009] S2, adding vanadium carbide to the dispersion for modification, stirring evenly, to obtain a spinning solution;

[0010] S3, degassing the spinning solution to obtain a treated solution from which bubbles are removed;

[0011] S4. Add the treated liquid into an electrospinning device, wherein the electrospinning device comprises a flow pump, wherein the flow pump is connected to a porous nozzle plate, and a parallel electrode collector is provided on a side of the porous nozzle plate away from the flow pump. The flow pump is used to control the flow rate of the treated liquid ejected from the porous nozzle plate to be 0.5 to 1.0 mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10 to 12 cm, the electrode distance of the parallel electrode collector is 15 to 20 cm, and the loading voltage is 20 to 30 KV. The obtained electrospun fibers are dried to obtain nanofiber membranes.

[0012] Furthermore, the polymer material is at least one of polylactic acid, polycaprolactone, polyglycolic acid, polylactic acid-glycolic acid copolymer, and chitosan-polylactic acid copolymer.

[0013] Furthermore, the solvent is a mixture of dichloromethane and dimethylformamide, and the volume ratio of dichloromethane to dimethylformamide is 2-3:1.

[0014] Furthermore, the mass concentration of the dispersion is 1-12%, preferably 3-10%, and more preferably 5-8%.

[0015] Furthermore, the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 13-15 parts by weight: 85-87 parts by weight.

[0016] Furthermore, the degassing treatment uses a vacuum pump to remove bubbles in the solution, and the degassing time is 30-300 minutes.

[0017] Furthermore, the electrode plate of the parallel electrode collector is made of copper, and the bracket and base of the electrode plate are made of insulating plastic, preferably polypropylene.

[0018] Furthermore, the flow rate of the treatment liquid sprayed from the porous nozzle plate is 0.7-1.0 mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10-12 cm, the electrode distance of the parallel electrode collector is 17-20 cm, and the loading voltage is 25-30 KV.

[0019] The present invention also protects the nanofiber membrane prepared by the preparation process of the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane, the fiber diameter of the nanofiber membrane is 200-250nm, the tensile strength is 100-120MPa, and the elongation at break is 5-10%.

[0020] The present invention also protects a photovoltaic aluminum profile wastewater treatment method, which uses the nanofiber membrane to treat the wastewater.

[0021] Beneficial effects: The preparation process of the nanofiber membrane provided by the present invention adopts a needle-free porous nozzle plate to emit the spinning solution, and uses parallel electrodes to stretch the fibers to obtain a uniformly arranged nanofiber membrane, thereby solving the clogging problem of the needle-type nozzle.

[0022] Furthermore, the preparation process of the nanofiber membrane provided by the present invention improves the tensile strength of the nanofiber membrane and the fiber diameter is below 250nm by controlling the flow rate of the spinning solution to be 0.5-1.0mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector to be 10-12cm, the electrode distance of the parallel electrode collector to be 15-20cm, and the loading voltage to be 20-30KV.

[0023] Furthermore, in the preparation process of the nanofiber membrane provided by the present invention, a modifier is added to the spinning solution, thereby improving the adsorption effect of the nanofiber membrane on metal ions, especially the removal effect on tin ions. 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 main reagents used include:

[0026] Solvent: A mixture of dichloromethane and dimethylformamide in a volume ratio of 2:1.

[0027] Example 1

[0028] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0029] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0030] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0031] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0032] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, a parallel electrode collector is provided on the side of the porous nozzle plate away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 15cm, the loading voltage is 20KV, and the electrospun fiber is obtained and then dried. After testing, 1g of nanofiber membrane was produced without nozzle clogging, and the uniformity of the membrane was good.

[0033] Example 2

[0034] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0035] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0036] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0037] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0038] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, a parallel electrode collector is provided on the side of the porous nozzle plate away from the flow pump, the flow rate of the treatment liquid ejected from the porous nozzle plate is controlled by the flow pump to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 15cm, the loading voltage is 10KV, and the electrospun fiber is obtained and then dried. After testing, 1g of nanofiber membrane was produced without nozzle clogging, and the uniformity of the membrane was good.

[0039] Example 3

[0040] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0041] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0042] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0043] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0044] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, a parallel electrode collector is provided on the side of the porous nozzle plate away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 15cm, the loading voltage is 25KV, and the electrospun fiber is obtained and then dried. After testing, the production of 1g nanofiber membrane did not cause nozzle clogging, and the uniformity of the membrane was good.

[0045] Example 4

[0046] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0047] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0048] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0049] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0050] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, the porous nozzle plate is provided with a parallel electrode collector on the side away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 20cm, the loading voltage is 30KV, and the electrospun fiber is obtained and then dried. After testing, the production of 1g nanofiber membrane did not cause nozzle clogging, and the uniformity of the membrane was good.

[0051] Example 5

[0052] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0053] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0054] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0055] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0056] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, the porous nozzle plate is provided with a parallel electrode collector on the side away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 1.0 mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10 cm, the electrode distance of the parallel electrode collector is 20 cm, the loading voltage is 30 KV, and the electrospun fiber is obtained and then dried. After testing, the production of 1g nanofiber membrane did not cause nozzle clogging, and the uniformity of the membrane was good.

[0057] Example 6

[0058] The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane comprises the following steps:

[0059] S1, dispersing polycaprolactone in a solvent to obtain a dispersion having a mass concentration of 5%;

[0060] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 13:87, and stirring evenly to obtain a spinning solution;

[0061] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0062] S4, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, the porous nozzle plate is provided with a parallel electrode collector on the side away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 20cm, the loading voltage is 30KV, and the electrospun fiber is obtained and then dried. After testing, the production of 1g nanofiber membrane did not cause nozzle clogging, and the uniformity of the membrane was good.

[0063] Performance Testing

[0064] The performance of the nanofiber membrane prepared in the example was tested, and the results are shown in Table 1.

[0065] Table 1 Nanofiber membrane performance test results

[0066]

[0067] As can be seen from Table 1, high voltage (20-30 kV) and large electrode distance (20 cm) can effectively stretch the fiber to produce thinner and stronger fibers. The elongation at break decreases as the fiber diameter decreases. The combination of 20-30 kV voltage and 15-20 cm electrode distance achieves the best fiber strength and diameter control.

[0068] Comparative Example 1

[0069] The conventional electrospinning process is as follows:

[0070] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0071] S2, adding vanadium carbide to the dispersion, wherein the mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 15:85, and stirring evenly to obtain a spinning solution;

[0072] S3, degassing the spinning solution, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment solution from which bubbles are removed;

[0073] S4, adding the treatment liquid to a conventional electrospinning device, the spinning voltage is 20KV, the electrospinning device has a single needle nozzle, the treatment liquid flows out through the single needle nozzle at a flow rate of 0.5mL / h, and an aluminum foil is used as a receiving plate with a receiving distance of 15cm, and then the electrospun fiber is obtained and dried. According to the test, the nozzle blockage occurs twice when producing 1g of nanofiber membrane.

[0074] Comparative Example 2

[0075] Referring to Example 1, the difference is that no modifier is added to the dispersion, as follows:

[0076] S1, dispersing polylactic acid in a solvent to obtain a dispersion having a mass concentration of 10%;

[0077] S2, degassing the dispersion liquid, using a vacuum pump to remove bubbles in the solution, the degassing time is 30 minutes, and obtaining a treatment liquid with bubbles removed;

[0078] S3, adding the treatment liquid to the electrospinning device, the electrospinning device includes a flow pump, the flow pump is connected to a porous nozzle plate, the porous nozzle plate is provided with a parallel electrode collector on the side away from the flow pump, the flow pump controls the flow rate of the treatment liquid ejected from the porous nozzle plate to be 0.5mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10cm, the electrode distance of the parallel electrode collector is 15cm, the loading voltage is 20KV, and the electrospun fiber is obtained and then dried. After testing, 1g of nanofiber membrane was produced without nozzle clogging, and the uniformity of the membrane was good.

[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 1 25g / L 15g / L 0.14g / L 0.10g / L Comparative Example 2 25g / L 15g / L 19.95g / L 11.51g / 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 preparation process of a needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane, characterized in that: The following steps are involved: S1, dispersing the polymer material into a solvent to obtain a dispersion; S2, adding vanadium carbide to the dispersion for modification, stirring evenly, to obtain a spinning solution; S3, degassing the spinning solution to obtain a treated solution from which bubbles are removed; S4. Add the treated liquid into an electrospinning device, wherein the electrospinning device comprises a flow pump, wherein the flow pump is connected to a porous nozzle plate, and a parallel electrode collector is provided on a side of the porous nozzle plate away from the flow pump. The flow pump is used to control the flow rate of the treated liquid ejected from the porous nozzle plate to be 0.5 to 1.0 mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10 to 12 cm, the electrode distance of the parallel electrode collector is 15 to 20 cm, and the loading voltage is 20 to 30 KV. The obtained electrospun fibers are dried to obtain nanofiber membranes.

2. The preparation process of the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to claim 1 is characterized by: The polymer material is at least one of polylactic acid, polycaprolactone, polyglycolic acid, polylactic acid-glycolic acid copolymer, and chitosan-polylactic acid copolymer.

3. The preparation process of the needle-free photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to claim 2, characterized in that: The solvent is a mixed solution of dichloromethane and dimethylformamide, and the volume ratio of dichloromethane to dimethylformamide is 2-3:

1.

4. The preparation process of the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to claim 3 is characterized by: The mass concentration of the dispersion is 1-12%, preferably 3-10%, and more preferably 5-8%.

5. The process for preparing the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to any one of claims 1 to 4, characterized in that: The mass ratio of the added amount of vanadium carbide to the polymer material in the dispersion is 13-15 parts by weight: 85-87 parts by weight.

6. The process for preparing the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to any one of claims 1 to 4, characterized in that: The degassing treatment uses a vacuum pump to remove bubbles in the solution, and the degassing time is 30-300 minutes.

7. The process for preparing the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to any one of claims 1 to 4, characterized in that: The electrode plate of the parallel electrode collector is made of copper, and the bracket and base of the electrode plate are made of insulating plastic, preferably polypropylene.

8. The process for preparing the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to any one of claims 1 to 4, characterized in that: The flow rate of the treatment liquid sprayed from the porous nozzle plate is 0.7-1.0 mL / h, the closest distance between the porous nozzle plate and the parallel electrode collector is 10-12 cm, the electrode distance of the parallel electrode collector is 17-20 cm, and the loading voltage is 25-30 KV.

9. A nanofiber membrane prepared by the preparation process of the needleless photovoltaic aluminum profile sewage treatment electrospinning nanofiber membrane according to any one of claims 1 to 8, characterized in that: The fiber diameter of the nanofiber membrane is 200-250nm, the tensile strength is 100-120MPa, and the elongation at break is 5-10%.

10. A photovoltaic aluminum profile wastewater treatment method, comprising treating the wastewater using the nanofiber membrane of claim 9.

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