阅读说明：本技术 一种高通量耐碱洗反渗透膜及其制备方法 (High-flux alkali-washing-resistant reverse osmosis membrane and preparation method thereof ) 是由 高翔 史晶晶 赵慧宇 于 2021-09-14 设计创作，主要内容包括：本发明提供了一种高通量耐碱洗反渗透膜及其制备方法,所述高通量耐碱洗反渗透膜,包括依次设置的反渗透底膜、疏导层和脱盐层；所述疏导层具有多孔结构,所述疏导层多孔结构的平均孔径d1限定为：d3<d1<d2,其中：d2为反渗透底膜的平均孔径,d3为脱盐层的平均孔径。由于疏导层的存在,不仅能够提高反渗透膜的耐碱清洗性能,还能够提高膜片的水通过速度却不影响膜片的盐通过速度,从而表现出膜片的脱盐率和水通量都有所提升。(The invention provides a high-flux alkali-washing-resistant reverse osmosis membrane and a preparation method thereof, wherein the high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the hydrophobic layer has a porous structure, and the average pore diameter d1 of the porous structure of the hydrophobic layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. Due to the existence of the dredging layer, the alkali-resistant cleaning performance of the reverse osmosis membrane can be improved, the water passing speed of the membrane can be improved, but the salt passing speed of the membrane is not influenced, so that the desalination rate and the water flux of the membrane are improved.)

1. A high-flux alkali-washing-resistant reverse osmosis membrane is characterized by comprising a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the hydrophobic layer has a porous structure, and the average pore diameter d1 of the porous structure of the hydrophobic layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

2. The high-throughput alkali-washing-resistant reverse osmosis membrane according to claim 1, wherein the main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin membrane layer, and the hydrophilic furfuryl alcohol resin membrane layer is prepared by mixing and curing furfuryl alcohol prepolymer and furfuryl alcohol monomer.

3. The high flux alkali-resistant reverse osmosis membrane of claim 2, wherein the thickness of the hydrophobic layer is 1-30 microns.

4. A method of preparing a high flux, base-resistant reverse osmosis membrane according to any one of claims 1-3 comprising the steps of:

obtaining a reverse osmosis basement membrane;

covering a hydrophobic layer on at least one surface of the reverse osmosis basement membrane;

forming a desalting layer on the surface of the dredging layer;

the hydrophobic layer has a porous structure, and the average pore diameter d1 of the porous structure of the hydrophobic layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

5. The method for preparing a high flux alkali-resistant reverse osmosis membrane according to claim 4, wherein the method comprises the following steps: the main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

6. The preparation method of the high-flux alkali-resistant reverse osmosis membrane according to claim 4 or 5, which is characterized by comprising the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into the furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

s2: coating the hydrophilic furfuryl alcohol resin obtained in the step S1-3 on a reverse osmosis base membrane, and baking the reverse osmosis base membrane to solidify the hydrophilic furfuryl alcohol resin to form a hydrophobic layer;

s3: and (4) forming a desalting layer on the sparse conducting layer obtained in the step S2 to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

7. The method for preparing a high flux alkali-resistant reverse osmosis membrane according to claim 6, wherein the desalting layer in step S3 is a polyamide membrane layer formed by the following steps:

dissolving m-phenylenediamine and camphorsulfonic acid triethylamine in water to prepare a water phase; dissolving trimesoyl chloride in an organic solvent Isopar G to form an organic phase; contacting the reverse osmosis basement membrane with the dredging layer formed in the step S2 with water, wetting the surface of the reverse osmosis basement membrane, and drying the residual water drops on the surface; and (3) contacting the reverse osmosis basement membrane with the residual water drops on the surface with the organic matter, removing the redundant organic matter, and baking to remove the residual organic matter, so as to form a desalting layer on the hydrophobic layer, thereby obtaining the high-flux alkali-washing-resistant reverse osmosis membrane.

8. The method for preparing a high flux alkali-resistant reverse osmosis membrane according to claim 6, wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows:

9. the method for preparing a high-flux alkali-resistant reverse osmosis membrane according to claim 6, wherein the baking temperature in the step S2 is 100-180 ℃, and the baking time is 10-300 seconds.

10. The method for preparing a high flux alkali-resistant reverse osmosis membrane according to any one of claims 4-9, wherein the reverse osmosis base membrane is polysulfone base membrane.

Technical Field

The invention belongs to the technical field of reverse osmosis membranes, and particularly relates to a high-flux alkali-washing-resistant reverse osmosis membrane and a preparation method thereof.

Background

Reverse osmosis is a membrane process that utilizes the selective permeability of reverse osmosis membrane that only permeates solvent to intercept ions or small molecular substances, and uses the static pressure difference at two sides of the membrane as driving force to separate mixture. The advancement of reverse osmosis membrane separation technology and economic, environmental and social benefits have been proved by the actual operation results of a large number of reverse osmosis projects. The core of the reverse osmosis membrane separation technology is a high-performance reverse osmosis membrane, and the reverse osmosis membrane needs to improve performance indexes such as water flux, desalination rate, pollution resistance, alkali resistance, corrosion resistance and the like.

Disclosure of Invention

In order to solve the defects of the prior art, the invention provides a high-flux alkali-washing-resistant reverse osmosis membrane and a preparation method thereof, and the improvement of the membrane desalination rate, water flux and alkali-washing resistance is realized mainly by adding a layer of hydrophilic furfuryl alcohol resin on a polysulfone base membrane.

The method is realized by the following technical scheme:

a high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the hydrophobic layer has a porous structure, and the average pore diameter d1 of the porous structure of the hydrophobic layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

Furthermore, the main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

Further, the thickness of the sparse conductive layer is 1-30 micrometers.

The invention also provides a preparation method of the high-flux alkali-washing-resistant reverse osmosis membrane, which comprises the following steps:

obtaining a reverse osmosis basement membrane;

covering a hydrophobic layer on at least one surface of the reverse osmosis basement membrane;

forming a desalting layer on the surface of the dredging layer;

the hydrophobic layer has a porous structure, and the average pore diameter d1 of the porous structure of the hydrophobic layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

Furthermore, the main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

Further, the method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into the furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

s2: coating the hydrophilic furfuryl alcohol resin obtained in the step S1-3 on a reverse osmosis base membrane, and baking the reverse osmosis base membrane to solidify the hydrophilic furfuryl alcohol resin to form a hydrophobic layer;

s3: and (4) forming a desalting layer on the sparse conducting layer obtained in the step S2 to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

Further, the desalting layer in step S3 is a polyamide film layer formed by the following steps:

dissolving m-phenylenediamine and camphorsulfonic acid triethylamine in water to prepare a water phase; dissolving trimesoyl chloride in an organic solvent Isopar G to form an organic phase; contacting the reverse osmosis basement membrane with the dredging layer formed in the step S2 with water, wetting the surface of the reverse osmosis basement membrane, and drying the residual water drops on the surface; and (3) contacting the reverse osmosis basement membrane with the residual water drops on the surface with the organic matter, removing the redundant organic matter, and baking to remove the residual organic matter, so as to form a desalting layer on the hydrophobic layer, thereby obtaining the high-flux alkali-washing-resistant reverse osmosis membrane.

Further, the weight ratio of each component in the steps S1-1 to S1-3 is as follows:

further, the baking temperature in the step S2 is 100-180 ℃, and the baking time is 10-300 seconds.

Further, the reverse osmosis basement membrane is a polysulfone basement membrane.

Compared with the prior art, the invention has the following advantages:

1. the invention is mainly characterized in that a layer of hydrophilic furfuryl alcohol resin is introduced between the polysulfone bottom membrane and the polyamide desalting layer, so as to improve the performance of the reverse osmosis membrane;

2. the solidified furfuryl alcohol resin has strong alkali resistance and mechanical strength, and can improve the alkali resistance cleaning performance of the reverse osmosis membrane;

3. the zinc chloride adopted during the preparation of the hydrophilic furfuryl alcohol resin plays a role of a curing agent, compared with the commonly used sulfuric acid curing agent of the furfuryl alcohol resin, the zinc chloride has lower curing speed, the furfuryl alcohol resin has lower curing degree and stronger hydrophilicity, and meanwhile, because small-molecular furfuryl alcohol monomers are not completely cured in the curing process, uncured furfuryl alcohol monomers can volatilize, so that the cured furfuryl alcohol resin is actually in a porous state, and the strong hydrophilic porous polymer film between the reverse osmosis base film and the desalting layer is favorable for improving the water flux of the film and has no adverse effect on the desalting rate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In general, a polysulfone membrane layer is mostly used as a base membrane, and a desalting layer such as polyamide is coated on the polysulfone base membrane. The polyamide desalting layer is of a porous structure with small and dense pores, can be used for filtering small-molecule salt and is beneficial to improving the desalting rate; the polysulfone base membrane is also porous and helps the water flow through. In the conventional technology, the effect of reverse osmosis filtration is realized by combining a polysulfone base membrane and a polyamide desalting layer. As the requirements on performance indexes such as reverse osmosis water flux, desalination rate and the like are higher and higher, a plurality of schemes for improving the water flux are provided in the prior art. Most of the components of the desalting layer are added with hydrophilic components, modified formulas and the like.

Based on the deep research on the reverse osmosis membrane, the dredging layer is creatively arranged between the bottom membrane and the desalting layer, so that the water flow cannot be blocked, and the water flux of the reverse osmosis membrane is improved. The specific mechanism is as follows:

although the bottom membrane and the desalting layer both have porous structures, the desalting layer such as polyamide has the functions of intercepting and adsorbing salt substances, so the pore size of the desalting layer is generally small, and the water flux is limited; the through holes of the polysulfone basement membrane do not need to play a role in desalination, and the aperture of the basement membrane is much larger than that of a desalination layer in order to ensure water flux and due to the polysulfone membrane forming process.

However, research shows that because the holes of the polysulfone bottom membrane are far away from each other, when water flows out of small holes in the desalting layer far away from the large holes in the polysulfone bottom membrane, a section of transverse water flow is generated between the polysulfone bottom membrane and the polyamide desalting layer in the process of flowing to the large holes in the polysulfone bottom membrane, and the transverse water flow can cause water flow blockage, so that the water flux of the reverse osmosis membrane is influenced.

A dredging layer is introduced between a reverse osmosis basement membrane and a desalting layer, and the dredging layer has a porous structure and can be used for water flow to pass through, so that the water flow is guided to flow to through holes of the basement membrane; and can play the effect of water collection buffering, make in the conventional art through the desalination layer and too late to flow to the rivers of basement membrane through-hole and carry out the short time and keep, guide to the through-hole of basement membrane again, flow out reverse osmosis membrane. Thereby achieving an increase in water flux.

Moreover, the hydrophilic furfuryl alcohol resin is creatively not taken as a modification component, but is independently formed into a film, and zinc chloride is taken as a curing agent, compared with the conventional curing agent sulfuric acid, the curing speed of the zinc chloride is lower, the curing degree of the furfuryl alcohol resin is lower, the furfuryl alcohol resin has stronger hydrophilicity, and meanwhile, because small-molecular furfuryl alcohol monomers are not completely cured in the curing process, the cured furfuryl alcohol resin is actually in a porous state, the furfuryl alcohol resin can play a role in dredging water flow, the generation of transverse water flow is reduced, the water passing speed is improved, and the water flux of the reverse osmosis membrane is improved. Meanwhile, the hydrophobic layer can improve the water passing speed of the membrane without influencing the salt passing speed of the membrane, so that the membrane shows that the desalination rate and the flux of the membrane are improved.

The method is realized by the following technical scheme:

a high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

Furthermore, the main body of the dredging layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

Further, the thickness of the dredging layer is 1-30 microns.

The invention also provides a preparation method of the high-flux alkali-washing-resistant reverse osmosis membrane, which comprises the following steps:

obtaining a reverse osmosis basement membrane;

covering a hydrophobic layer on at least one surface of the reverse osmosis basement membrane in a mode including but not limited to blade coating, slit coating and the like;

forming a desalting layer on the surface of the dredging layer;

the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer.

Furthermore, the main body of the dredging layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

Further, the method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

s2: coating the hydrophilic furfuryl alcohol resin obtained in the step S1-3 on the reverse osmosis base membrane, and baking the reverse osmosis base membrane to solidify the hydrophilic furfuryl alcohol resin to form a hydrophobic layer;

s3: and (4) forming a desalting layer on the sparse conducting layer obtained in the step S2 to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

Further, the desalting layer in step S3 is a polyamide film layer, and is formed by the following steps:

dissolving m-phenylenediamine and camphorsulfonic acid triethylamine in water to prepare a water phase; dissolving trimesoyl chloride in an organic solvent Isopar G to form an organic phase; contacting the reverse osmosis basement membrane with the dredging layer formed in the step S2 with water, wetting the surface of the reverse osmosis basement membrane, and drying the residual water drops on the surface; and (3) contacting the reverse osmosis basement membrane with the residual water drops on the surface with the organic matter, removing the redundant organic matter, and baking to remove the residual organic matter, so as to form a desalting layer on the hydrophobic layer, thereby obtaining the high-flux alkali-washing-resistant reverse osmosis membrane.

Further, the weight ratio of each component in the steps S1-1 to S1-3 is as follows:

further, the baking temperature in the step S2 is 100-180 ℃, and the baking time is 10-300 seconds.

Further, the reverse osmosis basement membrane is a polysulfone basement membrane.

The following examples are provided to further illustrate the beneficial effects of the present invention.

Furfuryl alcohol resin prepolymer: the polymerization degree of the furfuryl alcohol prepolymer is more than or equal to 4.

Example 1

A high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. The main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

The preparation method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows: 49% of furfuryl alcohol resin prepolymer, 49% of furfuryl alcohol monomer, 1% of zinc chloride and 1% of absolute alcohol.

S2: coating a layer of hydrophilic furfuryl alcohol resin with the thickness of 20 microns on a polysulfone bottom membrane in a scraping mode; baking the basement membrane coated with the hydrophilic furfuryl alcohol resin at 120 ℃ for 60 seconds to solidify the furfuryl alcohol resin to form a sparse conductive layer; then immediately putting the basement membrane into water for wetting and storing for later use.

S3: and forming a desalting layer on the hydrophobic layer obtained in the step S2, wherein the specific steps are as follows:

1) dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a layer of hydrophilic furfuryl alcohol resin added polysulfone basement membrane with water, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the hydrophilic furfuryl alcohol resin polysulfone basement membrane with the surface residual water drops removed with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

The sodium chloride solution with the concentration of 1500ppm is used as a test water source, the salt rejection rate of the reverse osmosis membrane is 99.53 percent under the test pressure of 1.03Mpa, and the water yield is 37.0L x m^-2*h^-1。

Example 2

A high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. The main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

The preparation method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows: 60% of furfuryl alcohol resin prepolymer, 38% of furfuryl alcohol monomer, 1% of zinc chloride and 1% of absolute alcohol.

S2: coating a layer of hydrophilic furfuryl alcohol resin with the thickness of 10 microns on a polysulfone bottom membrane in a scraping mode; baking the basement membrane coated with the hydrophilic furfuryl alcohol resin at 120 ℃ for 60 seconds to solidify the furfuryl alcohol resin to form a sparse conductive layer; then immediately putting the basement membrane into water for wetting and storing for later use.

S3: and forming a desalting layer on the hydrophobic layer obtained in the step S2, wherein the specific steps are as follows:

1) dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a layer of hydrophilic furfuryl alcohol resin added polysulfone basement membrane with water, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the hydrophilic furfuryl alcohol resin polysulfone basement membrane with the surface residual water drops removed with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

The salt rejection rate of the reverse osmosis membrane is 99.54 percent and the water yield is 36.7L m under the test pressure of 1.03Mpa by using a sodium chloride solution with the concentration of 1500ppm as a test water source^-2*h^-1。

Example 3

A high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. The main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

The preparation method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows: 20% of furfuryl alcohol resin prepolymer, 78% of furfuryl alcohol monomer, 1% of zinc chloride and 1% of absolute alcohol.

S2: coating a layer of hydrophilic furfuryl alcohol resin with the thickness of 5 microns on a polysulfone bottom membrane in a scraping mode; baking the basement membrane coated with the hydrophilic furfuryl alcohol resin at 120 ℃ for 60 seconds to solidify the furfuryl alcohol resin to form a sparse conductive layer; then immediately putting the basement membrane into water for wetting and storing for later use.

S3: and forming a desalting layer on the hydrophobic layer obtained in the step S2, wherein the specific steps are as follows:

1) dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a layer of hydrophilic furfuryl alcohol resin added polysulfone basement membrane with water, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the hydrophilic furfuryl alcohol resin polysulfone basement membrane with the surface residual water drops removed with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

The sodium chloride solution with the concentration of 1500ppm is used as a test water source, the salt rejection rate of the reverse osmosis membrane is 99.50 percent under the test pressure of 1.03Mpa, and the water yield is 37.3L m^-2*h^-1。

Example 4

A high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. The main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

The preparation method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows: 15% of furfuryl alcohol resin prepolymer, 83% of furfuryl alcohol monomer, 1% of zinc chloride and 1% of absolute alcohol.

S2: coating a layer of hydrophilic furfuryl alcohol resin with the thickness of 30 microns on a polysulfone bottom membrane in a scraping mode; baking the basement membrane coated with the hydrophilic furfuryl alcohol resin at 100 ℃ for 300 seconds to solidify the furfuryl alcohol resin to form a sparse conductive layer; then immediately putting the basement membrane into water for wetting and storing for later use.

S3: and forming a desalting layer on the hydrophobic layer obtained in the step S2, wherein the specific steps are as follows:

1) dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a layer of hydrophilic furfuryl alcohol resin added polysulfone basement membrane with water, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the hydrophilic furfuryl alcohol resin polysulfone basement membrane with the surface residual water drops removed with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

The sodium chloride solution with the concentration of 1500ppm is used as a test water source, the salt rejection rate of the reverse osmosis membrane is 99.48 percent under the test pressure of 1.03Mpa, and the water yield is 37.6L m^-2*h^-1。

Example 5

A high-flux alkali-washing-resistant reverse osmosis membrane comprises a reverse osmosis basement membrane, a dredging layer and a desalting layer which are sequentially arranged; the dredging layer has a porous structure, and the average pore diameter d1 of the porous structure of the dredging layer is defined as: d3< d1< d2, wherein: d2 is the average pore size of the reverse osmosis base membrane, d3 is the average pore size of the desalination layer. The main body of the hydrophobic layer is a hydrophilic furfuryl alcohol resin film layer, and the hydrophilic furfuryl alcohol resin film layer is prepared by mixing and curing a furfuryl alcohol prepolymer and a furfuryl alcohol monomer.

The preparation method specifically comprises the following steps:

s1-1: dissolving zinc chloride in absolute alcohol, and stirring to obtain an absolute alcohol suspension of the zinc chloride;

s1-2: dissolving the furfuryl alcohol prepolymer in a furfuryl alcohol monomer, and mixing to form a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution;

s1-3: then, gradually adding the anhydrous alcohol suspension of zinc chloride into a furfuryl alcohol prepolymer-furfuryl alcohol monomer resin solution, and stirring to obtain hydrophilic furfuryl alcohol resin;

wherein the weight ratio of each component in the steps S1-1 to S1-3 is as follows: 60% of furfuryl alcohol resin prepolymer, 38% of furfuryl alcohol monomer, 1% of zinc chloride and 1% of absolute alcohol.

S2: coating a layer of hydrophilic furfuryl alcohol resin with the thickness of 1 micron on a polysulfone bottom membrane in a scraping mode; baking the basement membrane coated with the hydrophilic furfuryl alcohol resin at 180 ℃ for 10 seconds to solidify the furfuryl alcohol resin to form a sparse conductive layer; then immediately putting the basement membrane into water for wetting and storing for later use.

S3: and forming a desalting layer on the hydrophobic layer obtained in the step S2, wherein the specific steps are as follows:

1) dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a layer of hydrophilic furfuryl alcohol resin added polysulfone basement membrane with water, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the hydrophilic furfuryl alcohol resin polysulfone basement membrane with the surface residual water drops removed with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the high-flux alkali-washing-resistant reverse osmosis membrane.

The sodium chloride solution with the concentration of 1500ppm is used as a test water source, the salt rejection rate of the reverse osmosis membrane is 99.52 percent under the test pressure of 1.03Mpa, and the water yield is 37.0L x m^-2*h^-1。

Comparative example

1) Dissolving m-phenylenediamine 2% and camphorsulfonic acid triethylamine 4% in water to prepare a water phase;

2) dissolving 0.20% of trimesoyl chloride in an organic solvent Isopar G to form an organic phase;

3) contacting a polysulfone basement membrane with a water phase, wetting the surface of the polysulfone basement membrane, and drying residual water drops on the surface;

4) and (3) contacting the polysulfone basement membrane with the residual water drops on the surface with an organic phase, removing redundant organic matters, and drying the residual organic matters in an oven to obtain the polyamide reverse osmosis membrane.

The sodium chloride solution with the concentration of 1500ppm is used as a test water source, the salt rejection rate of the reverse osmosis membrane is 99.45 percent under the test pressure of 1.03Mpa, and the water yield is 30.5L m^-2*h^-1。

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.