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CN-121973510-A - Energy-saving filter cloth based on nanofiber composite material and preparation method thereof

CN121973510ACN 121973510 ACN121973510 ACN 121973510ACN-121973510-A

Abstract

The invention relates to the technical field of energy conservation and environmental protection, in particular to an energy-saving filter cloth based on a nanofiber composite material and a preparation method thereof, wherein the energy-saving filter cloth comprises a supporting substrate layer, a bonding transition layer and a composite nanofiber filter layer which are sequentially compounded from inside to outside; the whole filter cloth adopts a three-layer composite structure of the supporting substrate layer, the bonding transition layer and the composite nanofiber filter layer, and the functions of the layers are complementary and cooperate to form a complete performance optimization system. The support substrate layer provides stable support, the bonding transition layer realizes interlayer tight connection, the composite nanofiber filter layer ensures high-efficiency filtration, and the combination of the three ensures that the filter cloth can obtain high filtration efficiency and simultaneously keep lower ventilation resistance.

Inventors

  • SONG LEI
  • Cong Duzhen
  • LV YAN
  • SONG JIE

Assignees

  • 安徽贝特滤材有限公司

Dates

Publication Date
20260505
Application Date
20251225

Claims (10)

  1. 1. The energy-saving filter cloth based on the nanofiber composite material is characterized by comprising a supporting substrate layer, a bonding transition layer and a composite nanofiber filter layer which are sequentially compounded from inside to outside; The supporting substrate layer is an environment-friendly glass fiber needled felt pretreated by argon plasma, and the porosity of the needled felt is 60-70%; the bonding transition layer is a polydimethylsiloxane crosslinked curing layer doped with nano silicon dioxide, and the thickness of the bonding transition layer is 1-2 mu m; the composite nanofiber filter layer is a functionalized graphene oxide/polyimide composite nanofiber layer.
  2. 2. The method for preparing energy-saving filter cloth based on nanofiber composite material according to claim 1, comprising the following steps: (1) Preparing functional graphene oxide, namely dispersing the graphene oxide in deionized water, performing ultrasonic dispersion for 30-40min to obtain GO dispersion liquid with the concentration of 0.6-1mg/mL, adding a compound system of an aminosilane coupling agent and a titanate coupling agent into the GO dispersion liquid, adjusting the pH value to 4-5, stirring at 60-80 ℃ for 2-4h, performing centrifugal separation at the rotating speed of 8000-10000r/min for 10-15min after the reaction is finished, pouring supernatant, reserving 1-2mL of precipitate at the bottom, merging the precipitate into a subsequent washing step, alternately washing for 3-5 times by using ethanol and deionized water, and performing vacuum drying at 60-80 ℃ for 8-12h to obtain the functional graphene oxide; (2) Preparing a composite spinning solution, namely dissolving polyimide powder in N, N-dimethylacetamide, magnetically stirring and dissolving the polyimide powder for 2-3 hours at the rotating speed of 200-300r/min at the temperature of 70-80 ℃ to obtain a PI solution with the concentration of 12-15wt%, adding the functionalized graphene oxide prepared in the step (1) into the PI solution, firstly performing ultrasonic dispersion for 20-30 minutes at the power of 150-200W, mechanically stirring the solution for 1-2 hours at the rotating speed of 300-500r/min, and stirring the solution until no obvious particle precipitation exists, thus obtaining the composite spinning solution; (3) The preparation method comprises the following steps of (1) pre-treating a supporting base material, namely sequentially ultrasonically cleaning an environment-friendly glass fiber needled felt by deionized water and ethanol for 10-15min respectively, and drying at 120 ℃ for 2-3h; (4) Preparing and solidifying a bonding transition layer, namely dispersing nano silicon dioxide in ethanol, adding a silane coupling agent KH550 accounting for 2-3% of the mass of the nano silicon dioxide, stirring and reacting for 1-2h at 50-60 ℃, and centrifugally drying to obtain pretreated nano silicon dioxide; uniformly mixing polydimethylsiloxane and a curing agent according to a mass ratio of 10:1, adding the pretreated nano silicon dioxide in 3-5 times in equal amount, stirring and dispersing for 10-15min after each addition until no obvious particle precipitation exists in the mixed solution, ultrasonically dispersing for 5-10min at a power of 150-200W to obtain PDMS coating solution, coating the PDMS coating solution on the surface of the pretreated substrate in the step (3) in a spraying manner, standing for 10-15min at room temperature, and curing for 1-2h in an oven at 80-100 ℃ to form a bonding transition layer; (5) The preparation of the composite nanofiber filter layer by electrostatic spinning comprises the steps of adding the composite spinning solution prepared in the step (2) into an injector of electrostatic spinning equipment, wherein the inner diameter of a needle head of the injector is 0.5-0.8mm, taking a base material with a bonding transition layer obtained in the step (4) as a receiving device, blowing nitrogen at a flow of 0.8-1L/min at a distance of 5-8cm from the needle head in the spinning process, enabling the blowing direction to form an angle of 45 ℃ with the spraying direction of the spinning solution, drying a sample in a 120 ℃ oven for 1-2h after the spinning is completed, removing residual solvent, performing heat setting treatment, and naturally cooling to room temperature under the protection of inert atmosphere to obtain the energy-saving filter cloth.
  3. 3. The method for preparing the energy-saving filter cloth based on the nanofiber composite material according to claim 2, wherein the addition amount of the compound system of the aminosilane coupling agent and the titanate coupling agent in the step (1) is 3-4% of GO dispersion liquid.
  4. 4. The method for preparing the energy-saving filter cloth based on the nanofiber composite material according to claim 3, wherein the aminosilane coupling agent is KH550 in a compound system of the aminosilane coupling agent and the titanate coupling agent, and the titanate coupling agent is NDZ-311.
  5. 5. The method for preparing the energy-saving filter cloth based on the nanofiber composite material, according to claim 2, wherein the mass fraction of the functionalized graphene oxide in the step (2) is 1-3% of the mass of polyimide.
  6. 6. The method for preparing the energy-saving filter cloth based on the nanofiber composite material, which is disclosed in claim 2, is characterized in that the plasma pretreatment parameters in the step (3) are that the power is 80-120W and the time is 3-5min.
  7. 7. The method for preparing energy-saving filter cloth based on nanofiber composite according to claim 2, wherein the curing agent in the step (4) is methyltriacetoxysilane.
  8. 8. The method for preparing the energy-saving filter cloth based on the nanofiber composite material, as claimed in claim 2, is characterized in that in the step (5), spinning parameters of 20-30kV voltage, 15-20cm of spinning distance, 0.5-1mL/h of spinning speed, 23+/-2 ℃ of ambient temperature and 18+/-2% of relative humidity are adjusted.
  9. 9. The method for preparing energy-saving filter cloth based on nanofiber composite material according to claim 2, wherein the heat setting treatment in the step (5) is carried out for 30min at 200 ℃.
  10. 10. The method for preparing energy-saving filter cloth based on nanofiber composite material according to claim 2, wherein the inert atmosphere in the step (5) is nitrogen or argon.

Description

Energy-saving filter cloth based on nanofiber composite material and preparation method thereof Technical Field The invention relates to the technical field of energy conservation and environmental protection, in particular to energy-saving filter cloth based on nanofiber composite materials and a preparation method thereof. Background The filter cloth is used as a core material in the field of filtration and separation, is widely applied to multiple scenes such as industrial flue gas purification, wastewater treatment, material recovery and the like, and the performance advantages and disadvantages of the filter cloth are directly related to the separation effect, the operation energy consumption and the service life of the filtration system. Along with the continuous improvement of global environmental protection requirements, industrial production brings more stringent requirements on comprehensive properties such as filtration precision, ventilation resistance, mechanical stability, temperature resistance, weather resistance and the like of filter cloth, and the traditional filter cloth is difficult to meet the use requirements under complex working conditions. The existing filter cloth products on the market have the technical problems that under the working conditions of long-term filter airflow impact, material friction and the like, the wear-resistant layer on the surface of the filter cloth is easy to be layered and fall off, so that the filter efficiency is rapidly reduced, and the service life of the filter cloth is greatly shortened. The traditional single fiber filter layer is difficult to achieve both high filtration efficiency and low air permeability resistance, if high filtration precision is pursued, the thickness or density of the fiber layer needs to be increased, the air permeability resistance is obviously increased, the operation energy consumption of a filter system is further increased, and if the air permeability resistance is reduced in a weight-bearing manner, the filtration precision cannot meet the interception requirement of tiny particles. The temperature resistance is insufficient, and part of filter cloth is obviously attenuated in mechanical property under high temperature working condition (such as high Wen Changjing in industrial flue gas purification), the filter layer structure is easy to deform and degrade, the filter function is invalid, and the application of the filter cloth in high temperature complex working condition is limited. In summary, the existing filter cloth still has technical defects to be solved in the aspects of interlayer bonding stability, filtration-energy consumption balance, temperature resistance and the like, and the development of the energy-saving filter cloth with high filtration efficiency, low ventilation resistance, strong chemical strength and good temperature resistance becomes an urgent requirement in the field of current filter materials, and has important significance in promoting the development of environment-friendly filtration technology. Disclosure of Invention The invention aims to provide an energy-saving filter cloth based on a nanofiber composite material. In order to achieve the above purpose, the present invention provides the following technical solutions: The energy-saving filter cloth based on the nanofiber composite material comprises a supporting substrate layer, a bonding transition layer and a composite nanofiber filter layer which are sequentially compounded from inside to outside; The supporting substrate layer is an environment-friendly glass fiber needled felt pretreated by argon plasma, and the porosity of the needled felt is 60-70%; the bonding transition layer is a polydimethylsiloxane crosslinked curing layer doped with nano silicon dioxide, and the thickness of the bonding transition layer is 1-2 mu m; the composite nanofiber filter layer is a functionalized graphene oxide/polyimide composite nanofiber layer. The preparation method of the energy-saving filter cloth based on the nanofiber composite material comprises the following steps: (1) Preparing functional graphene oxide, namely dispersing the graphene oxide in deionized water, performing ultrasonic dispersion for 30-40min to obtain GO dispersion liquid with the concentration of 0.6-1mg/mL, adding a compound system of an aminosilane coupling agent and a titanate coupling agent into the GO dispersion liquid, adjusting the pH value to 4-5, stirring at 60-80 ℃ for 2-4h, performing centrifugal separation at the rotating speed of 8000-10000r/min for 10-15min after the reaction is finished, pouring supernatant, reserving 1-2mL of precipitate at the bottom, merging the precipitate into a subsequent washing step, alternately washing for 3-5 times by using ethanol and deionized water, and performing vacuum drying at 60-80 ℃ for 8-12h to obtain the functional graphene oxide; (2) Preparing a composite spinning solution, namely dissolving polyimide powder in N, N