KR20150051137A - Separation membrane for water treatment and method for manufacturing the same - Google Patents

Abstract

Provided is a separator membrane for water treatment containing polysulfone and porous metal organic frameworks (MOFs), and a manufacturing method thereof. The provided separator membrane for water treatment according to an embodiment of the present invention comprises: a support layer containing polysulfone and porous MOFs; and an active layer. According to the present invention, the separator membrane for water treatment can increase porosity and hydrophilicity of the separator membrane for water treatment, and reduce the resistance of the surface of the separator membrane for water treatment.

Description

TECHNICAL FIELD [0001] The present invention relates to a separation membrane for water treatment,

And to a process for producing the same.

Membrane technology is attracting attention as a safe and environmentally friendly technology for water treatment.

In order to increase the hydrophilicity of the membrane, inorganic materials such as Al ₂ O ₃ , ZrO ₂ , TiO ₂ , CuO, and silica are added to polymer membranes.

Generally, separation membranes are contaminated with microorganisms and pollutants, so they require hydrophilic membranes and membranes with enhanced physico - chemical properties.

As a membrane material, polymer blending method is used to obtain materials with various characteristics rapidly and it shows high water permeability and permeation selectivity.

The present invention seeks to provide a water treatment separator comprising a polysulfone and a porous metal-organic framework (MOF).

However, the technical problem to be solved by the present invention is not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

The present invention provides a water treatment separator comprising a polysulfone and a porous metal-organic framework (MOF).

In one embodiment of the present invention, a support layer comprising a polysulfone and a porous metal-organic framework compound (MOF); And an active layer.

The porous metal-organic structural compound may include at least one selected from the group consisting of Cr MIL, IRMOF-1, MAMS, CuBTC (HKUST-1) and ZIF, and combinations thereof.

The porous metal-organic structural compound may be acid-treated to activate the OH group.

The porous metal-organic structural compound may be present dispersed in polysulfone.

The porous metal-organic structural compound may be contained in an amount of 0.2 to 10 parts by weight based on 100 parts by weight of the polysulfone.

The water treatment separation membrane may be a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, a reverse osmosis membrane or a normal osmosis membrane.

The thickness of the water treatment separator may be 100 탆 to 300 탆.

In another embodiment of the present invention, there is provided a process for preparing a casting composition comprising: (a) forming a casting solution comprising a polysulfone, a porous metal-organic structural compound and a polar aprotic organic solvent; (b) casting the casting solution onto a support and then immersing the casting solution in a non-solvent to solidify the polysulfone; And (c) washing the solidified polysulfone. The present invention also provides a method for producing a separator for water treatment.

 (d) subjecting the washed polysulfone to an interfacial polymerization reaction with a polyfunctional amine solution and a polyfunctional acyl halide solution.

The concentration of the polyfunctional amine solution may be 1.5 wt% to 3 wt%, and the concentration of the polyfunctional acyl halide solution may be 0.075 wt% to 0.15 wt%.

In the step (a), the porous metal-organic structural compound may be acid-treated and contained in the casting solution.

In the step (a), the polar aprotic organic solvent may include at least one selected from the group consisting of dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and combinations thereof.

In the step (a), the casting solution may contain 10 to 50 parts by weight of polysulfone and 0.1 to 1 part by weight of the porous metal-organic structural compound based on 100 parts by weight of the polar aprotic organic solvent.

In the step (a), the casting solution may further include at least one of a hydrophilic polymer additive and an organic acid phase transfer coagulation catalyst.

In the step (a), the support may be a film containing at least one of polyester, polypropylene, polyethylene, polyamide and polyimide, or may be a nonwoven fabric.

In the step (b), the casting solution may be cast on the support to a thickness of 100 to 300 탆.

When the water treatment separation membrane according to the present invention includes a metal-organic framework (MOF) and polysulfone polymer, it is possible to increase the porosity and hydrophilicity of the water treatment separation membrane and lower the resistance of the surface of the water treatment separation membrane, It is possible to prevent the hydrophobic pollutants from being adsorbed to the water treatment separator, to improve the stain resistance of the water treatment separator, and to improve the water permeation flow rate and the salt removal rate.

Furthermore, by acid-treating the metal-organic framework (MOF), the porosity and hydrophilicity of the water treatment separation membrane can be further increased, and the resistance of the surface of the water treatment separation membrane can be further reduced.

FIG. 1 is a flowchart schematically showing a method of manufacturing a separation membrane for water treatment according to an embodiment of the present invention.
2 shows the results of measurement of the water permeation flow rate for the water treatment separation membranes of Examples 3, 4, 2, and 5.
3 shows the results of measurement of water permeation flow rate for the water treatment separation membranes of Examples 1 and 2 and Comparative Example 1. Fig.
4 shows XPS analysis results of the water treatment membranes of Examples 1 and 2 and Comparative Example 1. Fig.
5 is a graph showing the results of measurement of permeation fluxes with time for the BSA solution to evaluate the stain resistance of the water treatment membranes of Examples 1 and 2 and Comparative Example 1. FIG.
6 is a graph showing MFI values calculated from the results of FIG.
7 is an image showing contact angle (?) Between the surface of the water-treating separation membrane support layer and water of Comparative Example 2, Example 6, Example 7, and Example 8. FIG.
Fig. 8 shows the results of measurement of the water permeation flow rate and the salt removal rate for the water treatment membranes of Example 7 and Comparative Example 2. Fig.
FIG. 9 shows results of ATR-FTIR analysis of damping total internal reflection (IR) spectroscopy on the surface of the separation membrane for water treatment of Example 7 and Comparative Example 2. FIG.
Fig. 10 shows results of field emission scanning electron microscopy (FE-SEM) analysis of the surface of the separation membrane for water treatment of Example 7 and Comparative Example 2. Fig.
11 is a scanning probe microscope (AFM) analysis result of the surface of a separation membrane for water treatment according to Example 7 and Comparative Example 2. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In one embodiment of the present invention, there is provided a water treatment separator comprising polysulfone and a porous metal-organic framework compound (MOF).

In another embodiment of the present invention, a support comprising a polysulfone and a porous metal-organic framework (MOF) compound; (PSF, polysulfone) is a thermoplastic resin having excellent physical and chemical properties as a material for producing a separator and having excellent thermal stability and mechanical strength. The water treatment separator includes a hydrophobic polysulfone together with a porous metal-organic structure compound (MOF) to improve hydrophilicity, thereby improving the water permeation flow rate and having excellent resistance to contamination.

The porous metal-organic structure compound (MOF) may be any material known as MOF without limitation. This porous metal-organic structure compound (MOF) is a crystalline compound having a constant skeleton in a three-dimensional form due to continuous bonding of a metal ion and an organic ligand. These organic ligands are coordinated with metal ions and are called coordination polymers, and the structures thus formed are similar in structure and properties to zeolite. In addition, the porous metal-organic structure compound (MOF) does not readily deform at high temperatures and has a rigid skeleton, which is excellent in chemical stability and thermal stability.

Since the porous metal-organic structure compound (MOF) generally has strong hydrophilicity to water and has a structural instability that dissolves in water, the porous metal-organic structure compound (MOF) By using it, the structural stability against water can be further improved. That is, by preliminarily treating the porous metal-organic structural compound with an acid prior to the film formation, it is possible to improve the structural stability to water as described above, so that when the porous metal-organic structural compound is used as a water treatment separation membrane, do.

In addition, the porous metal-organic structure compound (MOF) can be improved in the dispersion stability in the polysulfone by using an acid-treated and functional group introduced thereinto.

On the other hand, the porous metal-organic structure compound (MOF) contained in the water treatment separation membrane is hydrophilic as described above, thereby preventing the hydrophobic contaminants from being adsorbed on the separation membrane, thereby improving the stain resistance of the separation membrane.

Specific examples of the porous metal-organic structural compound (MOF) include Cr MIL, IRMOF-1, MAMS, CuBTC (HKUST-1), ZIF and the like.

The water treatment separator may contain the porous metal-organic structural compound (MOF) in an amount of about 0.2 to about 10 parts by weight based on 100 parts by weight of the polysulfone. By forming a separation membrane containing a polysulfone and a porous metal-organic structural compound (MOF) at a content ratio in the above content range, excellent characteristics of polysulfone as a membrane material, that is, thermal stability and mechanical strength, Excellent water permeability, stain resistance and the like can be imparted to the water treatment separator.

The water treatment separator may be formed of a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, a reverse osmosis membrane, or a osmosis membrane.

In general, the separation membrane used for water treatment has a reverse osmosis membrane, a nanofiltration membrane, an ultrafiltration membrane, and a microfiltration membrane depending on the size and structure of membrane pores. The reverse osmosis membrane can remove only univalent ions and finally pass only pure water. Ions (Ca ^{2 +} , Mg ^{2 +} , Fe ^{3 +,} etc.) and organic substances having a low molecular weight can be sufficiently removed. Ultrafiltration membranes can remove high molecular weight organics and various viruses. Finally, microfiltration membranes can control turbidity and remove various bacteria.

Specifically, the water treatment separator may be a microfiltration membrane or an ultrafiltration membrane.

The thickness of the water treatment separator may be adjusted depending on the type of the membrane, and may be, for example, about 100 탆 to about 300 탆.

The present invention also provides a method of forming a casting solution, comprising: (a) forming a casting solution comprising a polysulfone, a porous metal-organic structure compound (MOF) and a polar aprotic organic solvent; (b) casting the casting solution onto a support and then immersing the casting solution in a non-solvent to solidify the polysulfone; And (c) washing the solidified polysulfone. The present invention also provides a method for producing a separator for water treatment.

(d) subjecting the washed polysulfone to an interfacial polymerization reaction with a polyfunctional amine solution and a polyfunctional acyl halide solution.

FIG. 1 is a flowchart schematically showing a method of manufacturing a separation membrane for water treatment according to an embodiment of the present invention.

The method for producing the water treatment membrane may be a solvent-non-solvent phase transfer method, and the water treatment membrane may be produced by applying other known membrane forming methods.

Hereinafter, a specific method for producing the above water treatment separator will be described in detail.

Referring to FIG. 1, the method for preparing a water treatment separator includes a casting solution forming step (S110), a casting / phase transition step (S120), and a cleaning step (S130).

First, in a casting solution forming step (S110), a casting solution containing a porous metal-organic structural compound (MOF) and a polar aprotic organic solvent is formed in a melting tank.

The crude liquid of the casting solution may be made under a nitrogen atmosphere at about 60 ° C. It is preferable to thoroughly dissolve for more than 24 hours, and then ultrasonic vibration and a reduced pressure atmosphere are sequentially formed to sufficiently remove bubbles in the casting solution.

The polysulfone may be used in an amount of about 10 to about 50 parts by weight based on 100 parts by weight of the polar aprotic organic solvent. When the polysulfone is less than about 10 parts by weight based on 100 parts by weight of the polar aprotic organic solvent, it is insufficient as a filter material of an ultrafiltration membrane to be produced. Conversely, if the polysulfone is greater than about 50 parts by weight based on 100 parts by weight of the polar aprotic organic solvent, casting may be difficult due to excessive viscosity increase.

The polar aprotic organic solvent serves to dissolve the polysulfone. As the polar aprotic organic solvent, at least one of dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide and the like can be used.

The porous metal-organic structure compound (MOF) forms a complex with a polar aprotic organic solvent to improve hydrophilicity during solidification during the MOF polysulfone phase transition, thereby improving asymmetry. A detailed description of such a porous metal-organic structural compound (MOF) is as described above.

As noted above, acid-treated porous metal-organic structure compounds (MOF) may be used at this time.

Acid treatment of porous metal-organic structure compounds (MOF) increases the structural stability and activates OH groups in porous metal-organic structure compounds (MOFs), adding various kinds of acids to form hydrophilic conditions, To form a treated MOF.

More specifically, in the acid treatment of the porous metal-organic structural compound (MOF), a predetermined amount of an acid is added to a porous metal-organic structural compound (MOF), and a certain amount of an alcohol solvent is charged. After stirring for a predetermined time at room temperature, To remove the porous metal-organic structural compound (MOF), and to dry the resultant in an oven at a temperature of about 60 캜 or higher and for a time of about 24 hours.

The acid used in the acid treatment may be HCl, H ₂ SO ₄ , HNO ₃ , H ₂ CO ₃ , HCOOH, CH ₃ COOH, or the like. Specifically, the acid treatment concentration can proceed to a level at which the crystal structure of MOF is unbreakable (for example, pH 3), and the acid treatment time can be from about 1 hour to about 6 hours.

Examples of the alcohol include methyl alcohol, ethyl alcohol, propanol, and butanol.

The porous metal-organic structure compound (MOF) may be included in an amount of about 0.1 to about 1 part by weight based on 100 parts by weight of the polar aprotic organic solvent. If the addition amount of the porous metal-organic structural compound (MOF) is less than about 0.1 part by weight based on 100 parts by weight of the polar aprotic organic solvent, the effect of the addition may be insufficient. Conversely, when the amount of the porous metal-organic structural compound (MOF) added is more than about 1 part by weight based on 100 parts by weight of the polar aprotic organic solvent, the solution stability may be impaired.

The method for producing the water treatment separator is characterized in that the porous metal-organic structure compound (MOF) is added to the casting solution, thereby enabling pre-emulsifying before the casting solution is immersed in the coagulation bath in the solvent- To facilitate dispersion of the porous metal-organic structure compound (MOF) and the polysulfone.

The method of preparing the water treatment separator can be improved in hydrophilicity by the metal ions in the porous metal-organic structure compound (MOF), and therefore, by using the porous metal-organic structural compound (MOF) acid-treated in the casting solution The polarity of the casting solution can be further improved. The improvement of the polarity makes it possible to control the rate of water absorption of the surface in the precoagulation process, resulting in the pulling of the surface structure determination timing. As a result, it is possible to control the pore size and the asymmetry by controlling the content of the casting solution including the general porous metal-organic structure compound (MOF) and the acid-treated porous metal-organic structure compound (MOF). Whereby a microporous microfiltration membrane or an ultrafiltration membrane can be formed.

In addition, the casting solution to which the porous metal-organic structural compound (MOF) is added can realize homogeneous casting solution in the ion state of the hydrophilizing metal, thus enabling uniform surface hydrophilization.

The casting solution may further include a hydrophilic polymer additive for improving hydrophilicity, an organic acid phase coagulation catalyst for facilitating phase transition, and the like. When these hydrophilic polymer additives and organic acid phase coagulation catalysts are added, the addition amount thereof is preferably about 10 parts by weight or less based on 100 parts by weight of the polar aprotic organic solvent so as not to lower the physical properties of the ultrafiltration membrane to be produced desirable. The exposure relative humidity of the casting solution after casting to about 60 to about 80% before the impregnation may be between about 5 seconds and about 120 seconds. It is easy to form micro pores under the above-mentioned exposure humidity and exposure temperature conditions.

Next, in the casting / phase transition step (S120), the casting solution is cast on a support and immersed in a non-solvent to solidify the polysulfone.

The support may be a film containing at least one of polyester, polypropylene, polyethylene, polyamide and polyimide, or may be a nonwoven fabric.

The casting temperature, i.e. the temperature of the casting solution, can be maintained at about 5 to about 60 < 0 > C. If the temperature of the casting solution is below 5 ° C or above 60 ° C, it can adversely affect the pore size control and shrinkage.

The casting solution may be cast on the support to a thickness of about 100 [mu] m to about 300 [mu] m. Casting knives can be used for casting thickness control. When the casting thickness is less than about 100 탆, the strength of the ultrafiltration membrane to be produced may be lowered. Conversely, when the casting thickness exceeds about 300 탆, solvent-non-solvent substitution can become difficult to occur completely.

Purified water obtained by using a reverse osmosis membrane can be used as a non-coagulant.

At the phase transition by the non-solvent immersion, the temperature of the non-solvent can be from about 5 to about 40 캜. If the non-solvent temperature is less than about 5 占 폚 or more than 40 占 폚, solidification efficiency of the polysulfone may be lowered.

Next, in the cleaning step (S130), the polysulfone solidified in the washing tank is washed.

The cleaning bath can be composed of three stages and can proceed in water for from about 3 to about 16 times the coagulation bath immersion time.

The cleaning may be performed at about 25 to about 100 캜, and specifically about 40 to about 100 캜 for about 5 minutes or more. If the cleaning temperature is less than about 25 ° C, the cleaning efficiency may be lowered. Conversely, even if the cleaning temperature exceeds about 100 ° C, the cleaning effect can not be further improved as compared with the cleaning cost rise.

Next, in the interfacial polymerization reaction step (not shown), the washed polysulfone may be immersed in a polyfunctional amine solution and then immersed in a polyfunctional acyl halide solution to perform interfacial polymerization.

The concentration of the polyfunctional amine solution may be 1.5 wt% to 3 wt%, and the concentration of the polyfunctional acyl halide solution may be 0.075 wt% to 0.15 wt%.

At this time, the polyfunctional amine is a polyfunctional amine having at least two reactive amino groups, and examples thereof include aromatic, aliphatic and alicyclic polyfunctional amines.

Examples of the aromatic polyfunctional amine include m-phenylenediamine, p-phenylenediamine, o-phenylenediamine, 1,3,5-triaminobenzene, 1,2,4- Diaminobenzoic acid, 2,4-diaminobenzoic acid, 2,4-diaminotoluene, 2,6-diaminotoluene, N, N'-dimethyl- (Amidol), xylylenediamine, and the like. Examples of the aliphatic polyfunctional amine include ethylenediamine, propylenediamine, tris (2-aminoethyl) amine, n-phenyl-ethylenediamine and the like. Examples of alicyclic polyfunctional amines include 1,3-diaminocyclohexane, 1,2-diaminocyclohexane, 1,4-diaminocyclohexane, piperazine, 2,5-dimethylpiperazine 4-aminomethylpiperazine, and the like. These polyfunctional amines may be used alone or in combination of two or more. In order to obtain an active layer having a high salt-blocking property, it is preferable to use an aromatic polyfunctional amine, but the present invention is not limited thereto. In order to produce a denser active layer, it is preferable to use a trifunctional amine, but the present invention is not limited thereto.

The polyfunctional amine solution is prepared by dissolving a polyfunctional amine in water, wherein the content of the polyfunctional amine may be 1.5% by weight to 3% by weight based on the total weight of the polyfunctional amine solution.

The polyfunctional acyl halide is a polyfunctional acyl halide having two or more reactive carbonyl groups, including aromatic, aliphatic and alicyclic polyfunctional acyl halides.

As the aromatic polyfunctional acyl halide, there may be mentioned, for example, trimesic acid trichloride, terephthalic acid dichloride, isophthalic acid dichloride, biphenyldicarboxylic acid dichloride, naphthalene dicarboxylic acid dichloride, benzene triisulfonic acid trichloride, , Chlorosulfonylbenzene dicarboxylic acid dichloride, and the like. The aliphatic polyfunctional acyl halide includes, for example, propene dicarboxylic acid dichloride, butenedicarboxylic acid dichloride, pentane dicarboxylic acid dichloride, propylcarboxylic acid trichloride, butane tricarboxylic acid trichloride, pentane tricarboxylic acid tri Chloride, glutaryl halide, adipoyl halide and the like. The alicyclic polyfunctional acyl halide includes, for example, cyclopropane carboxylic acid trichloride, cyclobutane tetracarboxylic acid tetrachloride, cyclopentane tricarboxylic acid trichloride, cyclopentane tetracarboxylic acid tetrachloride, cyclohexane lycarboxylic acid trichloride , Tetrahydrofuran tetracarboxylic acid tetrachloride, cyclopentane dicarboxylic acid dichloride, cyclobutane dicarboxylic acid dichloride, cyclohexane dicarboxylic acid dichloride, tetrahydrofuran dicarboxylic acid dichloride and the like.

These polyfunctional acyl halides may be used alone or in combination of two or more. In order to obtain an active layer having a high salt-blocking ability, it is preferable to use an aromatic polyfunctional acyl halide, but the present invention is not limited thereto. In order to obtain a high rejection rate for ions, it is preferable, but not limited, to use a trivalent or more polyfunctional acyl halide in at least a part of the polyfunctional acyl halide component to form a dense three-dimensional crosslinked structure.

The polyfunctional acyl halide solution is prepared by dissolving a polyfunctional acyl halide in a solvent, wherein the content of the polyfunctional acyl halide may be 0.075 wt% to 0.15 wt% based on the total weight of the polyfunctional acyl halide solution.

Specifically, in the present invention, m-phenylenediamine is used as the multifunctional amine monomer for production of the active layer, trimethoyl chloride is used as the polyfunctional acyl halide, and n-hexane is used as the solvent of the polyfunctional acyl halide . After the interfacial polymerization, unreacted materials on the surface were removed using NaHCO ₃ solution.

Hereinafter, examples and comparative examples of the present invention will be described. The following embodiments are only examples of the present invention, and the present invention is not limited to the following embodiments.

Example

Manufacturing example  1: acid treated MOF  Ready

MOF was prepared by HKUST-1 [Cu ₃ (btc) ₂ ] (Basolite C300, Sigma Aldrich). HKUST-1 is based on Cu and is linked by benzenetricarboxylic acid (btc) as a paddle-wheel unit. The compound has a hole size of 1 nm in the 3D channel and has high thermal stability and high water durability compared to other MOF. HKUST-1 has crossed three-dimensional channels of ~ 9 Å in diameter and is surrounded by tetrahedral side pockets with ~ 5 Å in diameter. And a pore of ~ 3.5 Å which connects the channel and the side pocket.

The HKUST-1 was diluted with sulfuric acid (98 wt%) and acid-treated at pH 3. The concentration of sulfuric acid was diluted to pH 3, and a certain amount of HKUST-1 was added to a round flask and stirred with ethanol for 4 hours. Thereafter, the MOF is decompressed using a paper filter and dried in an oven at 50 ° C. for 24 hours under vacuum to obtain an acid-treated MOF (HKUST-1).

Example  One

After drying at 100 ° C for 24 hours to remove unreacted impurities in PSF (UDEL P-3500 LCD, Solvay, USA), 16 wt% PSF and HKUST-1 [Cu ₃ (btc) ₂ ] (Basolite C300, Sigma Aldrich), and DMF (83.5 wt%). The mixture was stirred at a stirring speed of 30 rpm and at room temperature for 24 hours or more in a nitrogen atmosphere so as not to generate fine bubbles. In order to prevent agglomeration of the casting solution, a membrane was formed immediately after completion to prepare a water treatment separation membrane.

Example  2

After drying at 100 DEG C for 24 hours to remove unreacted impurities in PSF (UDEL P-3500 LCD, Solvay, USA), 16 wt% PSF, 0.5 wt% MOF acid treated in Preparation 1, and DMF A casting solution was prepared at a composition ratio of 83.5 wt%. The mixture was stirred at a stirring speed of 30 rpm and at room temperature for 24 hours or more in a nitrogen atmosphere so as not to generate fine bubbles. In order to prevent agglomeration of the casting solution, a membrane was formed immediately after completion to prepare a water treatment separation membrane.

Example  3

A water treatment membrane was prepared in the same manner as in Example 2 except that the content of MOF was set to 0.1 wt% and the content of DMF was set to 83.9 wt%.

Example  4

A water treatment separation membrane was prepared in the same manner as in Example 2, except that the content of MOF was changed to 0.25 wt% and the content of DMF was changed to 83.75 wt%.

Example  5

A water treatment separation membrane was prepared in the same manner as in Example 2, except that the content of MOF was 1.0 wt% and the content of DMF was 83 wt%.

Example  6

After drying at 100 DEG C for 24 hours to remove unreacted impurities in PSF (UDEL P-3500 LCD, Solvay, USA), 18 wt% PSF, 0.25 wt% MOF acid treated in Preparation 1, and DMF The casting solution was prepared at a composition ratio of 81.75 wt%. The mixture was stirred at a stirring speed of 30 rpm and at room temperature for 24 hours or more in a nitrogen atmosphere so as not to generate fine bubbles. In order to prevent the agglomeration of the casting solution, a support layer was formed by a film forming process.

The support layer was immersed in the 2 wt% m-phenylenediamine solution at room temperature for 2 minutes so that the amine monomer could be sufficiently absorbed into the pores of the support layer, and then the excess solution existing on the surface was removed using a roller. The support layer was fixed using a Teflon frame (Taflon Flame) and a silicon frame (Silicon Flame), and then immersed in a 0.05 wt% trimesoyl chloride solution to perform interfacial polymerization. The polymer was recovered and dried at room temperature for 1 minute, 2000ppm NaHCO ₃ to remove Solution for 1 hour and then stored in distilled water for 24 hours.

Example  7

A water treatment separation membrane was prepared in the same manner as in Example 6, except that the content of PSF was 18 wt%, the content of MOF was 0.5 wt%, and the content of DMF was 81.5 wt%.

Example  8

A water treatment separation membrane was prepared in the same manner as in Example 6, except that the content of PSF was 18 wt%, the content of MOF was 0.75 wt%, and the content of DMF was 81.25 wt%.

Comparative Example  One

After drying at 100 ° C for 24 hours to remove unreacted impurities in PSF (UDEL P-3500 LCD, manufactured by Solvay (USA)), a casting solution was prepared at a composition ratio of 16 wt% of PSF and 84 wt% of DMF. The mixture was stirred at a stirring speed of 30 rpm and at room temperature for 24 hours or more in a nitrogen atmosphere so as not to generate fine bubbles. In order to prevent agglomeration of the casting solution, a membrane was formed immediately after completion to prepare a water treatment separation membrane.

Comparative Example  2

A water treatment separation membrane was prepared in the same manner as in Example 6, except that the content of PSF was 18 wt%, the content of MOF was 0 wt%, and the content of DMF was 82 wt%.

evaluation

Experimental Example  One

The water treatment membranes prepared in Example 3, Example 4, Example 2 and Example 5 (MOF contents of 0.1 wt%, 0.25 wt%, 0.5 wt% and 0.1 wt% in order) were subjected to water permeation The measurement of the water flux is shown in Fig.

 [Equation 1]

2, L is the amount of water (liter) passing through the membrane, M is the area of the membrane (m ² ), and H is the time (hour) through which the water passes. That is, it is an evaluation unit of how many liters of water have passed through the membrane area of 1 m ² for one hour.

The water permeation flow rate of the separator increased in the order of Example 3, Example 4, and Example 2, but in the separator membrane of Example 5 containing 1.0 wt% And the flow rate was decreased. The reason for this is that a large amount of added additives coagulate with each other and the water permeation flow rate is reduced.

Experimental Example  2

The water permeation flow rates of the water treatment membranes of Examples 1 and 2 and Comparative Example 1 were measured by the following formula (1), and the results are shown in FIG.

[Equation 1]

3, LMH means the amount of water passing per unit time. L is the amount of water (liters) passing through the membrane, M is the area of the membrane (m ² ), and H is the time (hour) through which it passes. That is, it is an evaluation unit of how many liters of water have passed through the membrane area of 1 m ² for one hour.

From the results shown in FIG. 3, it can be seen that the water permeability of 33% and 72% was improved in Examples 1 and 2 including MOF, respectively, as compared with Comparative Example 1.

Experimental Example  3

X-ray photoelectron spectrometer (X-ray photoelectron spectrometer, K-Alpha, Thermo Electron) was used to analyze the hydrophilicity and chemical structure of the membranes of the water treatment membranes of Examples 1, 2 and Comparative Example 1. Figure 4 shows the XPS analysis results.

4, there is no peak corresponding to Cu in Comparative Example 1, and a peak corresponding to CuO appears at 933.36 eV in Example 1, and a peak corresponding to Cu, CuO and Cu (OH) ₂ in Example 2 931.98 eV, 933.38 eV and 934.78 eV, respectively. It is expected that the OH peak is present in Example 2 using an acid-treated MOF, and thus it will have a better hydrophilicity than that of Example 1. [

Experimental Example  4

The contact angles of the water treatment membranes of Examples 1 and 2 and Comparative Example 1 were measured (FTA-200, manufactured by First Ten Angstroms) to evaluate their hydrophilic properties and are shown in Table 1 below. From the results shown in Table 1, it was confirmed that the hydrophilicity was increased as the contact angles of Examples 1 and 2 were reduced as compared with Comparative Example 1. [

Experimental Example  5

After the water treatment membranes of Examples 1 and 2 and Comparative Example 1 were used, inductively coupled plasma (ICEM) (LEEMAN, model: Direct Reading Echelle) was used to identify Cu metal in the eluted MOF in the permeated water. And the results are shown in Table 1 below. From the results of Table 1, it was confirmed that Cu ion was not measured and elution was not observed in Example 2 using the acid-treated MOF.

Comparative Example 1 Example 1 Example 2 Contact angle (°) 72.7 66.9 59.0 Cu ion concentration (ppm) Not detected 0.053 0.001 Not detected

Experimental Example  6

The stain resistance of the water treatment membranes of Examples 1 and 2 and Comparative Example 1 was evaluated by the following methods.

Using dead-end transmission equipment, at a pressure of 1 kg _f / cm ² 100 ppm bovine serum albumin (BSA) was added. FIG. 5 shows the result of the permeation flow rate reduction evaluation by filtering for more than 1 hour.

Example 1 and Example 2 exhibited a higher permeate flow rate than Comparative Example 1. < tb > < TABLE > It is understood that this is because the presence of hydrophilic MOF in the separator prevents the adsorption of BSA molecules on the surface.

Fig. 6 shows the result of calculating the MFI index in order to evaluate the stain resistance increase of Examples 1 and 2 in more detail. The MFI value is a value having a linear slope in the graph of V and t / V at a constant pressure. The smaller the value is, the more the stain of the film is improved. As a result, it was found that the MFI values of Examples 1 and 2 were smaller than those of Comparative Example 1. As a result, it was found that the addition of MOF and acid-treated MOF improved the stain resistance of the existing PSF membrane have.

Experimental Example  7

(FTA-200, First Ten Angstroms) was used to examine the hydrophilicity of the surfaces of the water treatment membranes of Comparative Examples 2, 6, 7 and 8, The film surface changes were measured.

7, the contact angle (?) Between the surface of the support layer and the water of the water treatment membrane according to the Comparative Example 2 is 68.5 °, while the contact angle between the surface of the support layer of the water treatment membrane according to Examples 6 to 8 and the water ) Was 58.8 to 64.7 °. In the case of Examples 6 to 8, hydrophilicity of the surface of the support layer of the water treatment separator was higher than that of Comparative Example 2, which is a result of acid-treated MOF.

Experimental Example  8

To measure the water permeation flow rate and the salt removal rate for the water treatment membranes of Example 7 and Comparative Example 2, a water treatment separator having an area of 27.01 cm 2 was prepared, and 2000 ppm of NaCl at a supply pressure of 19.5 bar, The experiment was carried out by supplying the aqueous solution. At this time, the water permeation flow rate was measured by stabilizing the support layer for 2 hours, measuring the permeate volume for 30 minutes, and calculating the water permeation flow rate of the water treatment membrane.

&Quot; (2) "

The salt removal rate was measured using a conductivity meter (Istek, 460 CP), and the salt removal rate of the water treatment membrane was calculated by the following equation (3).

&Quot; (3) "

As shown in FIG. 8, the water treatment membrane of Example 7 had a water permeation flow rate of 27.65 GFD and a salt removal rate of 95.7%, which was ultimately superior to that of the water treatment membrane of Comparative Example 2 in both water flow rate and salt removal rate I could confirm.

Experimental Example  9

The surfaces of the water treatment membranes of Example 7 and Comparative Example 2 were analyzed for chemical bonding by an attenuated total internal reflection infrared spectrophotometer (ATR-FTIR). Specifically, when infrared rays are injected into a sample, a spectrum is generated by absorbing the wavelength of the unique region of each chemical bond. By analyzing the spectrum, the chemical bond is analyzed.

As shown in FIG. 9, the surface of the separation membrane for water treatment of Example 7 and Comparative Example 2 was analyzed. As a result, peaks of the same pattern were observed in a range of 450 to 2000 cm ^-1 , which is a typical spectrum of the polysulfone polymer. Also, peaks of the same pattern were observed in the range of 1660, 1609, and 1547 cm ^-1 , which was confirmed to be the spectrum of the polyamide polymer. Specifically, 1660cm ^{- 1} denotes a peak of C = O stretching, CN stretching, CCN deformation vibration as AmideⅠ band, a peak of 1609cm ^-1 indicates the deformation vibration NH, C = C ring stretching vibration as Aromatic amide band, 1547cm ^{- one} of the peak indicates the NC stretching vibration in the NH and the -CO-NH- group as AmideⅡ band.

That is, the chemical bonding of the surface of the water treatment membrane through the ATR-FTIR revealed that the polyamide bond was clearly observed, and it was confirmed that the water treatment membrane was formed through the interfacial polymerization. This is the result of the increased hydrophilicity of the support layer in Example 7, in which m-phenylenediamine is easily diffused and adsorbed on the support layer to form an active layer comprising a thin polyamide polymer.

Experimental Example  10

The surfaces of the water treatment membranes of Example 7 and Comparative Example 2 were analyzed by field emission scanning electron microscopy (FE-SEM).

As shown in FIG. 10, ridge and vally structures were commonly observed in the water treatment membranes of Example 7 and Comparative Example 2, and the cross-link structure of amide bonds was clearly observed. The surface of the water treatment membrane according to Comparative Example 2 showed a ridge and valley structure, whereas Example 7 showed a smooth ridge and vally structure, and the reverse osmosis membrane containing MOF exhibited basic polyamide characteristics. This is the result of the increased hydrophilicity of the support layer in Example 7, in which m-phenylenediamine is readily diffused and adsorbed on the support layer to form an active layer comprising a uniform polyamide polymer.

Experimental Example  11

(AFM) of the surface of the water treatment membrane according to Example 7 and Comparative Example 2. [

As shown in FIG. 11, in the case of Example 7, incorporation of the acid-treated MOF in the support layer increased the porosity and hydrophilicity of the support layer and affected the roughness factor of the surface of the separation membrane for water treatment. That is, in the case of the surface of the water treatment membrane according to Example 7, the roughness factor, that is, the surface roughness value, was decreased as compared with the surface of the water treatment membrane according to Comparative Example 2. As a result of incorporating the acid-treated MOF into the support layer in Example 7, the porosity and hydrophilicity of the support layer were increased, which affected the roughness factor of the surface of the separation membrane for water treatment. That is, since the surface of the separation membrane for water treatment according to Example 7 has the hydrophilic property and the porosity of the support layer, the m-phenylenediamine solution easily diffuses and adsorbs to the support layer to form the active layer containing the thin polyamide polymer, And the water permeation flow rate of the water treatment separator can be increased.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Claims (17)

Polysulfone and porous metal-organic structure compounds (MOF, Metal-Organic frameworks).
A supporting layer comprising polysulfone and porous metal-organic framework compounds (MOF); And
A separator for water treatment comprising an active layer.
3. The method according to claim 1 or 2,
Wherein the porous metal-organic structural compound comprises at least one selected from the group consisting of Cr MIL, IRMOF-1, MAMS, CuBTC (HKUST-1) and ZIF,
Separation membrane for water treatment.
3. The method according to claim 1 or 2,
The porous metal-organic structural compound is acid-treated to activate the OH group
Separation membrane for water treatment.
3. The method according to claim 1 or 2,
When the porous metal-organic structural compound is dispersed in polysulfone and is present
Separation membrane for water treatment.
3. The method according to claim 1 or 2,
The porous metal-organic structural compound is contained in an amount of 0.2 to 10 parts by weight based on 100 parts by weight of the polysulfone
Separation membrane for water treatment.
3. The method according to claim 1 or 2,
The water treatment separator may be a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, a reverse osmosis membrane,
Separation membrane for water treatment.
3. The method according to claim 1 or 2,
Wherein the thickness of the water treatment separator is 100 mu m to 300 mu m
Separation membrane for water treatment.
(a) forming a casting solution comprising a polysulfone, a porous metal-organic structural compound, and a polar aprotic organic solvent;
(b) casting the casting solution onto a support and then immersing the casting solution in a non-solvent to solidify the polysulfone; And
(c) cleaning the solidified polysulfone;
Wherein the separation membrane comprises a water-soluble organic solvent.
10. The method of claim 9,
(d) interfacially polymerizing the washed polysulfone with a polyfunctional amine solution and a polyfunctional acyl halide solution
A method for producing a water treatment separator.
11. The method of claim 10,
The concentration of the polyfunctional amine solution is 1.5 wt% to 3 wt%, and the concentration of the polyfunctional acyl halide solution is 0.075 wt% to 0.15 wt%
A method for producing a water treatment separator.
10. The method of claim 9,
In the step (a), the porous metal-organic structural compound is acid-treated and contained in the casting solution
A method for producing a water treatment separator.
10. The method of claim 9,
In the step (a), the polar aprotic organic solvent includes at least one selected from the group consisting of dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and combinations thereof
A method for producing a water treatment separator.
10. The method of claim 9,
In the step (a), the casting solution contains 10 to 50 parts by weight of polysulfone and 0.1 to 1 part by weight of the porous metal-organic structural compound based on 100 parts by weight of the polar aprotic organic solvent
A method for producing a water treatment separator.
10. The method of claim 9,
In the step (a), the casting solution further comprises at least one of a hydrophilic polymer additive and an organic acid phase transfer coagulation catalyst
A method for producing a water treatment separator.
10. The method of claim 9,
In the step (a), the support may be a film containing at least one of polyester, polypropylene, polyethylene, polyamide and polyimide,
A method for producing a water treatment separator.
10. The method of claim 9,
(B) casting the casting solution to a thickness of 100 to 300 탆 on the support
A method for producing a water treatment separator.

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