CN211435781U

CN211435781U - Porous copper-clad titanium dioxide nano antibacterial particle composite nanofiltration membrane

Info

Publication number: CN211435781U
Application number: CN201922038444.5U
Authority: CN
Inventors: 段伟; 杨瀚
Original assignee: Shenzhen Reamem Membrane Technology Co ltd
Current assignee: Shenzhen Reamem Membrane Technology Co ltd
Priority date: 2019-11-22
Filing date: 2019-11-22
Publication date: 2020-09-08
Anticipated expiration: 2029-11-22

Abstract

The utility model discloses a compound filter membrane that receives of antibiotic granule in porous copper clad titanium dioxide nanometer, it includes the polypiperazine amide separating layer that stacks up on the ultrafiltration support membrane layer, polypiperazine amide separating layer comprises in the antibiotic particle dispersion embedding polypiperazine amide membrane of porous nanometer. The number of the porous copper-coated titanium dioxide nano antibacterial particles embedded in the surface of the polypiperazine amide separating layer is more than that of the porous copper-coated titanium dioxide nano antibacterial particles embedded in the polypiperazine amide separating layer. The utility model discloses the compound nanofiltration membrane of porous copper clad titanium dioxide nanometer antibacterial particle water flux who makes is big, the desalination rate is high, anti bacterial pollution, easy washing, can wide application in sewage treatment, application fields such as the desalination of material concentration, buck or sea water.

Description

Porous copper-clad titanium dioxide nano antibacterial particle composite nanofiltration membrane

Technical Field

The utility model relates to a membrane separation technical field, concretely relates to compound filter membrane that receives of porous copper cladding titanium dioxide nanometer antibacterial particle.

Background

Nanofiltration is a novel membrane separation technique between ultrafiltration and reverse osmosis. The operating pressure range is 0.2-1.0MPa, and the molecular weight cut-off of the membrane is within the range of 200-1000. The nanofiltration membrane has the characteristics of low operating pressure, high removal rate of salts with more than two valences, low removal rate of monovalent salts and the like. Nanofiltration membranes are widely applied to water recycling, water softening, medicine, food, biology and other industries at present. In the practical application process, the nanofiltration membrane is invaded by fast growing bacteria in water to cause microbial pollution, so that the flux and the desalination rate of the nanofiltration membrane are reduced, the using efficiency and the service life of the membrane are seriously affected, the microbial pollution becomes an important factor influencing the development of reverse osmosis technology, and particularly, the bacterial pollution is almost an important source of membrane pollution in the field of drinking water and pure water treatment, including softened water systems widely applied in the market. Therefore, the method can kill bacteria on the surface of the membrane and reduce the membrane pollution trend, and becomes the development direction of the application of the nanofiltration membrane.

In the current industrial application, the bactericide is added into water to reduce bacterial pollution, and the introduction of the bactericide needs to additionally introduce a reducing agent to neutralize the oxidability of the bactericide, so that the nanofiltration membrane is protected from being damaged by the oxidizing agent, the cost is increased, and the risk of damage to the nanofiltration membrane is increased; the method of chemically modifying the surface of the membrane, such as grafting a chemical substance with bactericidal property to the surface of the nanofiltration composite membrane by means of chemical coupling, ultraviolet rays or plasma, is complex in operation or reaction conditions, high in manufacturing cost and difficult to realize on a production line; the method of coating an antibacterial and pollution-resistant layer on the surface layer of the nanofiltration composite membrane is not acceptable because antibacterial substances are easy to lose. At present, composite nano antibacterial particles are increasingly paid more attention in the preparation process of the nanofiltration membrane.

The antibacterial material mainly comprises inorganic, organic and natural macromolecular antibacterial agents. The research and application of the nano-silver antibacterial agent of the inorganic antibacterial agent are the most extensive, the market share is high, but the countries in Europe and America have found that the nano-silver has safety risks to human health, so that the related application of the nano-silver material is limited. Copper is a trace element needed by human bodies, and in 3 months of 2008, the united states Environmental Protection Agency (EPA) confirms that copper can kill harmful and possibly fatal germs, and copper is the only metal bacteriostatic material which is certified by the united states Environmental Protection Agency (EPA), so that the adoption of nano copper-based antibacterial agents with biological safety becomes a safer choice. The copper-coated titanium dioxide novel nano antibacterial particles (see fig. 1 and fig. 3) have a long-acting metal ion release effect, can have a good antibacterial and mildewproof function under a dark condition, and are novel nano antibacterial particles with biological safety. However, after the antibacterial composite material is compounded into a nanofiltration membrane material, the particle size of the antibacterial composite material is larger than or equal to that of the membrane pores of the nanofiltration membrane, so that the membrane pore size is blocked, and the membrane flux is reduced while the antibacterial performance of the membrane surface is improved.

Therefore, how to overcome the defect that the existing nanofiltration membrane cannot give consideration to both good antibacterial property of the membrane surface and large membrane flux is a problem to be solved in the industry.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a solve current receive filter membrane can't compromise the technical problem that the membrane surface antibacterial property is good and have membrane flux big again, provide an antibiotic effect and show lasting, long service life's compound filter membrane of receiving of porous nanometer antibacterial particle.

The utility model provides a compound filter membrane of receiving of antibiotic granule in porous copper clad titanium dioxide nanometer has, including range upon range of the polypiperazine amide separating layer on ultrafiltration supporting film layer, polypiperazine amide separating layer comprises in the porous nanometer antibiotic particle dispersion embedding polypiperazine amide membrane.

Preferably, the number of the porous copper-clad titanium dioxide nano antibacterial particles embedded in the surface of the polypiperazine amide separating layer is more than that of the porous copper-clad titanium dioxide nano antibacterial particles embedded in the polypiperazine amide separating layer.

Preferably, the ultrafiltration support membrane layer is formed by coating an ultrafiltration membrane on a non-woven fabric.

Preferably, the porous copper-clad titanium dioxide nano antibacterial particle is provided with a plurality of micro through holes, and the surface of the particle is provided with metal copper particles.

Preferably, the polypiperazine amide membrane material is distributed in fine through holes in the porous copper-clad titanium dioxide nano antibacterial particles.

The porous copper-coated titanium dioxide nano antibacterial particles used by the utility model have good hydrophilicity, more internal through holes and small aperture (a)<2 nm) and no ecological risk, and (1) after the nano antibacterial particles are compounded with a nanofiltration membrane material, the surface hydrophilicity of the membrane can be increased due to the excellent hydrophilicity of the nano antibacterial particles, and the nano antibacterial particles are favorable for improving the water flux of the membrane and reducing pollution. (2) The nano antibacterial particles are internally provided with a large number of through holes, and the membrane liquid can penetrate into the holes to form wedges to firmly fix the nano antibacterial particles, so that the binding force between the nano antibacterial particles and the membrane material is greatly increased, and the antibacterial effect of the nano antibacterial particles is ensured not to be attenuated along with time (see figure 4), thereby obviously improving the membrane flux and simultaneously ensuring the high rejection rate of the nanofiltration membrane to ions and molecules. (3) The abundant through holes inside the nano antibacterial particles can not block the membrane pores (because water can pass through the pores). Thereby obviously improving the membrane flux and ensuring the high retention rate of the nanofiltration membrane to ions and molecules. (4) Copper-coated TiO2₂The nano particles have excellent antibacterial performance, can be enriched on the surface of the membrane after being compounded into the membrane material, can greatly reduce the bacterial growth on the surface of the membrane, improve the antibacterial and anti-pollution performance on the surface of the composite nanofiltration membrane, have no biological hazard to human bodies and environment, and have no ecological risk in large-scale use. And the copper compound is cheaper than the silver compound, so that the manufacturing cost of the nano antibacterial particles can be reduced, and the manufacturing cost of the antibacterial film can be reduced. (5) Because the utility model provides a compound nanofiltration membrane water flux improves, and when the desalination was stable, antibiotic antipollution performance also improved, reduced membrane chemical cleaning frequency by a wide margin, prolonged the life of membrane to reduce membrane operation and maintenance cost, reduce water treatment engineering operation and maintenance cost。

Drawings

FIG. 1 is a schematic diagram of a conventional nano-ceramic particle;

FIG. 2 is a schematic view of the porous copper-clad titanium dioxide nano antibacterial particle of the present invention;

FIG. 3 is a schematic diagram of the combination of common nano-ceramic particles with membrane material;

FIG. 4 is a schematic view of the combination of the porous copper-coated titanium dioxide nano antibacterial particles and the nanofiltration membrane material of the present invention;

fig. 5 is a schematic cross-sectional view of the porous copper-clad titanium dioxide nano antibacterial particle composite nanofiltration membrane of the present invention.

Detailed Description

As shown in figure 2, figure 4 and figure 5, the composite nanofiltration membrane of the porous copper-coated titanium dioxide nano antibacterial particles prepared by the preparation method of the utility model comprises a polypiperazine amide separation layer 3 on a laminated ultrafiltration support membrane layer 4, wherein the polypiperazine amide separation layer 3 is formed by dispersing and embedding porous nano antibacterial particles 1 into a polypiperazine amide membrane 2. The particle 1 has on its outer surface a metallic copper particle having a plurality of through-holes 5 therein for the penetration of a liquid. The polypiperazine amide separating layer 3 has a structure with asymmetric density along the cross section direction, namely, the number of the porous copper-coated titanium dioxide nano antibacterial particles 1 embedded in the surface of the polypiperazine amide separating layer 3 is larger than that of the porous copper-coated titanium dioxide nano antibacterial particles embedded in the polypiperazine amide separating layer. The ultrafiltration support membrane layer 4 is formed by coating an ultrafiltration membrane 6 on a non-woven fabric 7. Wherein the polyamide separation layer 3 on the surface of the membrane determines the separation performance, the ultrafiltration support membrane layer 4 on the lower layer is a support layer, and the porous copper-coated titanium dioxide nano antibacterial particles 1 are dispersed and embedded in the polypiperazine amide membrane 2 and are enriched on the surface of the membrane. The trace raw materials of the polypiperazine amide film can also be distributed at the edge of the through hole 5 of the nano antibacterial particle 1 and in the through hole so as to strengthen the fixation of the nano antibacterial particle 1.

The porous copper-clad titanium dioxide nano antibacterial particle composite nanofiltration membrane can be obtained by the following steps: gradually dispersing and embedding porous copper-coated titanium dioxide nano antibacterial particles into a separation membrane, and compounding the separation membrane with the embedded particles with an ultrafiltration support membraneThe surface of the layer is provided with the porous copper-clad TiO₂A nano antibacterial particle composite nanofiltration membrane. The porous copper-coated titanium dioxide nano antibacterial particles are dispersedly embedded into the separation membrane and are enriched on the membrane surface of the composite nanofiltration membrane, and trace components of the composite nanofiltration membrane can also be distributed at the edge of the through hole of the nano antibacterial particle or embedded into the through hole so as to strengthen the fixation of the nano antibacterial particle.

According to the content of the porous copper-clad titanium dioxide nano antibacterial particles added into the separation membrane layer, the following embodiments are provided:

examples 0 to 6:

the basic structures of the composite nanofiltration membranes provided by the embodiments 0 to 6 are the same, but the contents of the porous copper-coated titanium dioxide nano antibacterial particles compositely embedded in the polypiperazine amide membrane are different, and the ratios of the particles to the polypiperazine amide are respectively as follows: 0 percent (not added), 0.05 percent, 0.25 percent, 0.5 percent, 1 percent, 2.5 percent and 5 percent to prepare seven composite nanofiltration membranes.

Comparative example:

the composite nanofiltration membrane is the same as the basic structure of the embodiment 0-6, except that 2.5% (the ratio of the antibacterial particles to the polypiperazine amide) of common non-porous copper-coated titanium dioxide nano antibacterial particles are embedded into the polypiperazine amide membrane to obtain the composite nanofiltration membrane.

The prepared nanofiltration membrane is tested for pure water flux and desalination in a nanofiltration membrane test method GB/T , wherein the test method is 34242-2017; the antibacterial test of the nanofiltration membrane can be carried out according to the standard experimental method of the antibacterial activity determination of the fixed antibacterial agent under the dynamic contact condition of ASTM E2149-2013 a. Table 1 shows porous copper-coated TiO films prepared in examples 0 to 6₂And (3) a performance parameter table of the nano antibacterial particle composite nanofiltration membrane.

TABLE 1

The composite nanofiltration membrane was soaked in tap water, the soaking water was changed every day, and samples were taken every other month to test the antibacterial performance of the membrane surface, with the results shown in table 2. The result shows that the antibacterial effect of the porous antibacterial nano-particle composite nanofiltration membrane changes little with time, mainly because the binding force between the porous nano-particles and the membrane material is high, and the porous antibacterial nano-particle composite nanofiltration membrane cannot fall off and run off, so that the good antibacterial performance can be maintained. Table 2 is a table of comparative parameters of long-term antibacterial performance of example 5 and comparative examples.

TABLE 2

Example 7:

step one is the same as the above embodiment;

step two: preparation of porous copper-coated TiO2 nano antibacterial particle composite antibacterial nanofiltration membrane

Wrapping 18% (ratio to piperazine) of porous copper with TiO₂The nano particles are added into 2.75wt% piperazine water solution, and the nano particles are uniformly dispersed in the solution by adopting ultrasonic oscillation for 80 min.

Immersing the wet polysulfone support membrane into the aqueous solution of piperazine for 4min, removing the excess aqueous solution on the surface of the polysulfone support membrane by using a blower, pouring 0.95wt% of trimesoyl chloride solution onto the surface of the polysulfone support membrane, and carrying out interfacial polymerization for 50 s. And (3) drying the composite membrane in the air for 4min, then carrying out heat treatment on the composite membrane, and treating the composite membrane at 100 ℃ for 2 min to obtain the nano porous antibacterial particle composite nanofiltration membrane. And soaking the nanofiltration membrane in pure water, and washing for 24 hours to be detected. Table 3 shows porous copper-coated TiO prepared in example 7₂And (3) a performance parameter table of the nano antibacterial particle composite nanofiltration membrane.

TABLE 3

The nanofiltration membrane was soaked in tap water, the soaking water was changed every day, and samples were taken every other month to test the antibacterial performance of the membrane surface, with the results shown in table 4. The result shows that the antibacterial effect of the porous antibacterial nano-particle composite nanofiltration membrane changes little with time, mainly because the binding force between the porous nano-particles and the membrane material is high, and the porous antibacterial nano-particle composite nanofiltration membrane cannot fall off and run off, so that the good antibacterial performance can be maintained. Table 4 is a table of parameters for long-term antimicrobial performance of example 7.

TABLE 4

The utility model discloses the porous copper cladding titanium dioxide nanometer antibacterial particle of preparation has metal copper granule at its surface parcel, not only gives titanium dioxide nanometer granule more excellent antibiotic antipollution performance, remains the porous structure of nanometer granule moreover simultaneously, forms to the pure water passageway. In addition, the copper is adopted to replace silver to wrap the nano particles, so that the cost of the nano antibacterial particles is reduced, and the ecological safety of the nano antibacterial material is improved. Porous copper-clad TiO with long-acting antibacterial effect₂The nano antibacterial particle composite nanofiltration membrane is beneficial to embedding a membrane material into pores and enhancing the binding force between the nano particles and the membrane material due to the generation of pores inside the porous nano particles, so that the nano particles cannot fall off and run away in the long-term use process, and the long-acting property of the nano antibacterial effect is ensured; on the other hand, the gaps of the nano particles cannot block the water permeation of the holes of the nanofiltration membrane, so that the flux of the forward osmosis membrane cannot be influenced. The utility model discloses a compound filter membrane of receiving, flux and entrapment rate all have the improvement of certain degree, increase substantially membrane surface antibacterial property moreover, can delay the membrane pollution that compound received the filter membrane, are favorable to reducing compound and receive filter membrane use and maintenance cost.

The utility model provides a compound nanofiltration membrane of porous copper clad titanium dioxide nanometer antibacterial particles water flux is big, the desalination rate is high, anti bacterial pollution, easy washing, can wide application in sewage treatment, application fields such as the desalination of material concentration, buck or sea water.

The above description is only for the preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. The porous copper-coated titanium dioxide nano antibacterial particle composite nanofiltration membrane is characterized by comprising a polypiperazine amide separation layer laminated on an ultrafiltration support membrane layer, wherein the polypiperazine amide separation layer is formed by dispersing and embedding porous copper-coated titanium dioxide nano antibacterial particles into a polypiperazine amide membrane.

2. The porous copper-coated titanium dioxide nano antibacterial particle composite nanofiltration membrane of claim 1, wherein the number of the porous copper-coated titanium dioxide nano antibacterial particles embedded in the surface of the polypiperazine amide separation layer is greater than the number of the porous copper-coated titanium dioxide nano antibacterial particles embedded in the polypiperazine amide separation layer.

3. The porous copper-coated titanium dioxide nano antibacterial particle composite nanofiltration membrane of claim 1, wherein the ultrafiltration support membrane layer is formed by coating an ultrafiltration membrane on a non-woven fabric.

4. The porous copper-coated titanium dioxide nano antibacterial particle composite nanofiltration membrane of claim 1, wherein the porous copper-coated titanium dioxide nano antibacterial particle has a plurality of fine through holes, and the surface of the particle has metal copper particles.

5. The porous copper-clad titanium dioxide nano antibacterial particle composite nanofiltration membrane of claim 4, wherein the polypiperazine amide membrane material is distributed in the fine through holes in the porous copper-clad titanium dioxide nano antibacterial particles.