KR20170014642A - Renewable water-treatment membranes and method for manufacturing the same - Google Patents

Abstract

Provided is a renewable water-treatment separation membrane, comprising a membrane substrate, and a diene-dienophile coupling coupler introduced on at least one surface of the membrane substrate. The diene-dienophile coupling coupler comprises: a diene-derived functional group introduced on at least one surface of the membrane substrate and a substance containing a dienophile-derived functional group coupled with the diene-derived functional group; or a dienophile-derived functional group introduced on at least one surface of the membrane substrate and a substance containing the diene-derived functional group coupled with the dienophile-derived functional group.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a water-

The present invention relates to a regenerable water treatment membrane and a method of manufacturing the same, and more particularly, to a water treatment membrane that can be reused through regeneration of functionality and a method of manufacturing the same.

The water treatment method through the membrane is simple, small installation space and low energy consumption compared to the conventional physical, chemical, and biological water treatment methods, but has an advantage of excellent purification ability and its usage is gradually increasing.

However, there is a problem that when the water treatment is performed using the separation membrane, the pollutants to be removed accumulate on the surface of the separation membrane or the internal pores, resulting in a problem of fouling of the separation membrane, thereby shortening the life of the separation membrane.

In order to suppress the adhesion of the hydrophobic contaminants causing the separation membrane fouling, materials capable of decomposing hydrophilic materials or contaminants may be coated or grafted on the surface of the separation membrane, Attempts have been made to form membranes using mixed dope solutions.

Such attempts may delay the membrane fouling rate and prolong the life of the membrane, but if the treatment limit of the chemical fouling functional material is reached, the entire membrane must be replaced in order to recover the membrane performance.

Further, in order for the functionalities desired to be imparted to be expressed in the separator to be developed, it is necessary to develop an appropriate introduction process for each function, so that a large amount of manufacturing cost and development time are required, and therefore, technology development is still required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a separable membrane that can be reused without replacing the entire separation membrane, and a method for producing the same.

Other objects and advantages of the present invention will become apparent from the following description. It is also to be easily understood that the objects and advantages of the present invention can be realized by a means or a method described in the claims and a combination thereof.

According to an aspect of the present invention, there is provided a membrane-electrode assembly including a separator substrate, and a diene-dithiane-based coupling coupler introduced on at least one surface of the separator substrate, Containing polymeric functional group-derived functional group-containing functional group-containing functional group-containing functional group-derived functional group-derived functional group-introduced functional group-containing functional group-derived functional group-derived functional group-derived functional group- And a diene-containing functional group-containing substance coupled to the functional group-derived functional group derived from the polyimide.

The separator substrate may be formed of at least one of a polymer material, an inorganic material, and a metal material.

The polymeric material may be selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polysulfone (PSF), polyethersulfone (PES), polyacrylonitrile PAN, Polycarbonate (PC), Polyethylene (PE), Polypropylene (PP), Polyvinyl Chloride (PVC), Cellulose and Cellulose Acetate And at least one selected from the group consisting of

The inorganic material may be at least one of aluminum oxide (Alumina), silicon oxide, and titanium oxide.

The metal material may be at least one of stainless steel and palladium alloy.

The dienes may include at least one selected from the group consisting of butadiene, cyclopentadiene, pyrrole and furan.

The polyimide may include at least one selected from the group consisting of acrylonitrile, quinone, maleic anhydride, and maleimide.

The above-mentioned functional group-containing substance derived from a polythiophene may be a substance into which a pendant functional group is introduced into at least one of inorganic particles, metal particles and hydrophilic polymer.

The diene-containing functional group-containing substance may be a substance in which a functional group derived from a diene is introduced into at least one of the inorganic particles, the metal particles and the hydrophilic polymer.

According to another aspect of the present invention, there is provided a method of manufacturing a regenerable water treatment separator comprising the step of introducing a diene-dithiocyanate coupling coupler on at least one surface of a separator.

The step of introducing the diene-dithiane coupling coupler comprises a step of introducing a functional group derived from a diene onto at least one surface of the separator base material and a step of adding a functional group- And coupling the functional group to the functional group-derived functional group.

Wherein the step of introducing the diene-dithiane coupling coupler comprises the steps of introducing a functional group derived from a phosphorus-containing substance onto at least one surface of the separation membrane base material, and adding a functional group- And coupling the functional group and the diene-derived functional group.

The step of coupling the functional group derived from the diene with the functional group derived from the polyimide may be performed by a Diels-Alder reaction.

The step of coupling the functional group derived from the dienes and the functional group derived from the polyfunctional groups may be performed at a temperature of 20 to 70 ° C.

According to another embodiment of the present invention, water containing contaminants is treated with the above-described water treatment separation membrane to attach contaminants to the diene-dithiane coupling coupler, , Dissociating the coupling between the diene-derived functional group and the functional group-derived functional group of the diene-dithiane coupling coupler group to remove contaminants, and reacting the functional group- Containing functional group-containing substance to the functional group-derived functional group to recombine the functional group-derived functional group and the functional group-derived functional group.

The temperature at which the water-treated separation membrane is heated may be 80 to 200 ° C.

The step of dissociating the coupling may be a retro Diels-Alder reaction.

The present invention can provide a water treatment separation membrane that can be regenerated without replacement of the entire separation membrane by introducing a diene-dithiane coupling group capable of reversibly binding and dissociation by temperature into the separation membrane surface.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate preferred embodiments of the invention and, together with the description of the invention, It is not interpreted.
1 is a schematic perspective view of a regenerable water treatment separator according to an embodiment of the present invention.
FIG. 2 is an FE-SEM photograph showing the PEG attachment and desorption process of the separation membrane prepared in Example 1. FIG.
FIG. 3 is a graph showing the fouling reduction performance and the regeneration performance of the separation membrane produced in Example 1. FIG.

Hereinafter, the present invention will be described in detail. The terms and words used in the specification and claims should not be construed in a conventional or dictionary sense to mean that the inventor has defined the concept of a term appropriately to describe its invention in the best way. It should be construed as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, at the time of the present application, It should be understood that various equivalents and modifications are possible.

1 is a schematic perspective view of a regenerable water treatment separator according to an embodiment of the present invention. 1, a regenerable water treatment membrane 100 according to one embodiment of the present invention includes a membrane substrate 10 and a diene-dithiocyanurate coupling coupler 40 , And the diene-dithiane coupling coupler (40) is introduced on at least one surface of the separation membrane base material (10), and a functional group derived from the diene-based functional group Derived functional group (30), which is coupled to at least one surface of the separation membrane substrate (10), or a functional group derived from the polyimide (20) derived from the polyimide Containing functional group-containing substance (30) coupled with the diene-containing functional group-containing substance (20).

The separator substrate applicable to the present invention may be applied to any material applied in the art without limitation, and may be formed of any one of a polymer material, an inorganic material, or a metallic material, or a mixture thereof, without limitation.

The polymer material may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polysulfone (PSF), polyethersulfone (PES), polyacrylonitrile Polyacrylonitrile (PAN), Polycarbonate (PC), Polyethylene (PE), Polypropylene (PP), Polyvinyl Chloride (PVC), Cellulose and Cellulose Acetate ), Preferably polytetrafluoroethylene (PTFE), polyvinylidenefluoride (PVDF), polysulfone (PSF), poly (vinylidene fluoride), poly And polyethersulfone (PES), or a mixture thereof.

The inorganic material usable as the separation membrane substrate may be at least one of aluminum oxide (Alumina), silicon oxide, and titanium oxide, or a mixture thereof may be used. Stainless steel, and palladium alloy, or a mixture thereof may be used.

In addition, the above-described material may be used as the separator substrate, or the surface thereof may be modified to at least one selected from the group consisting of OH, -NH ₂ , -CN, -CO-, -COOH, and -CONH-.

The separator substrate includes a diene-dithiane coupling coupler on one or both sides.

The dienes applicable to the present invention are materials having a structure in the order of a double bond-single bond-double bond, and materials having an s-cis diene form can be used without limitation. Butadiene, Cyclopentadiene, Pyrrole and Furan, or a mixture thereof, preferably Furan, may be used.

Also, the pendant diene may be coupled with a diene to form a ring, and the pendant diene applicable to the present invention may be any material including a double bond or a triple bond without limitation , And non-limiting examples include acrylonitrile, quinone, maleic anhydride maleimide, and mixtures thereof, preferably maleimide (maleimide) Maleimide).

The diene-dithiane coupling coupler may be a reversible covalent bond, which is a result of a reversible chemical reaction between a diene and a pseudo-diene, and which can bond and dissociate.

The reversible chemical reaction applicable to the present invention is a reaction capable of regulating the forward and reverse reactions by changing the temperature, pressure, and the concentration of the substance in a thermodynamically equilibrium state. As a preferable example, the Diels- (Diels-Alder reaction).

The Diels-Alder reaction is an organic chemical reaction of conjugated dienes and pseudoenes, in which a mixture of conjugated dienes and p-dienes is charged with energy such as heat , The reaction proceeds and the cyclic cyclohexane is formed and the reverse reaction dissociates the cyclic hexane to form a mixture of the conjugated diene and the pendant.

In the present invention, by introducing a diene-dithiane coupling coupling group formed by the above-described Diels-Alder reaction into the surface of a water treatment separation membrane, it is possible to regenerate a separation membrane whose performance has been deteriorated by fouling without replacement of the separation membrane .

More specifically, when the surface of the water treatment separation membrane with contaminants attached thereto is heated to a high temperature, a retro-Diels-Alder reaction proceeds to dissociate the diene-dithiane coupling bond. Such coupling-coupled dissociation can easily remove contaminants, and by reintroducing a pure diene-dithiocyanate coupling at a suitable temperature, the functionality imparted to the separator can be regenerated.

The diene-dithiane coupling coupler that can be applied to the present invention is a compound having a functional group derived from a diene introduced into one side or both sides of a separation membrane substrate and a functional group derived from a dibenzene- ≪ / RTI >

Also, according to another embodiment, the diene-dithiane coupling coupler may be formed by coupling a functional group-derived functional group introduced on one side or both sides of the separation membrane with a functional group derived from a diene- Containing material.

At this time, the diene-based functional group introduced into the separation membrane substrate or the functional group-derived functional group derived from the polyene copolymer introduced into the separation membrane substrate is independently 0.1 to 30 parts by weight, preferably 1 to 10 parts by weight Can be.

The functional group-containing substance derived from the dibenzene which can be applied to the present invention may be a hydrophilic substance into which a pendant diene functional group is introduced. According to another embodiment, the diene-containing functional group- And may be variously applied to the membrane substrate so as to form a diene-dithiocyanate coupling coupler with a functional group bonded to the membrane substrate.

At this time, the hydrophilic substance applicable to the present invention may be any one of a material capable of introducing a pendant diene functional group or a dienes functional group without limitation, preferably one of an inorganic particle and a metal particle hydrophilic polymer, More specifically, it may be a typical polyethylene glycol (polyethyleneglycol) among the hydrophilic polymers.

The content of the hydrophilic substance may be 1 to 30 parts by weight, preferably 2 to 15 parts by weight, based on 100 parts by weight of the membrane material.

The content of the functional group-containing substance derived from dienes is 0.1 to 30 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the separation membrane base material into which the functional group derived from a polyfunctional agent forming a coupling- Can be.

The content of the functional group-containing substance derived from the pendantene is 0.1 to 30 parts by weight, preferably 1 to 10 parts by weight, per 100 parts by weight of the separating membrane base material into which the functional group derived from the diene- .

Hereinafter, the same structure as the above-mentioned regenerable water treatment membrane production method and the water treatment membrane separation method, which will be described later, will be described in detail when it is determined that repetition of the description may unnecessarily obscure the gist of the present invention It is needless to say that the present invention can be omitted, but the same can be applied.

A method of manufacturing a regenerable water treatment separation membrane according to another embodiment of the present invention includes introducing a diene-dithiocyanurate coupling coupler on at least one surface of a separation membrane.

According to a preferred embodiment of the present invention, the step of introducing the diene-dithiane coupling coupler comprises the steps of introducing a functional group derived from a diene onto at least one surface of the separator base, Containing substance to the functional group-derived functional group.

According to another embodiment of the step of introducing the diene-dithiane coupling coupler, a step of introducing a functional group derived from a polythiophene into at least one surface of the separator base material and a step of introducing a functional group- To the functional group-derived functional group.

At this time, the diene-dithiane coupling coupler may be formed by a Diels-Alder reaction of a functional group derived from a diene and a functional group derived from a polyene, and the reaction is carried out at 20 to 70 ° C, Preferably at 40 to < RTI ID = 0.0 > 60 C. < / RTI >

According to another embodiment of the present invention, there is provided a method of regenerating a water treatment separation membrane, comprising the steps of: water-treating a water containing a pollutant with the water treatment separation membrane to attach a contaminant to a diene-dithiane coupling coupler; Subjecting the water treatment membrane to heat treatment to dissociate the coupling between the diene-derived functional group and the polyene-based functional group of the diene-dithiane coupling coupler to remove contaminants; And a functional group-derived substance derived from a diene or a functional group-containing substance derived from a polyimide are added to recombine the functional group derived from the diene and the functional group derived from the polyene.

The step of heat-treating the water-treated separation membrane to dissociate the coupling between the diene-derived functional group and the polyene-based functional group of the diene-dithiane coupling coupler to remove the contaminants is carried out by using a diene- The reaction capable of breaking the bond of the s-coupling coupler may be variously applied, but it may preferably be a retro Diels-Alder reaction.

At this time, the temperature for the heat treatment is 80 to 200 ° C, preferably 100 to 150 ° C, and the retro Diels-Alder reaction does not proceed outside the temperature range.

Hereinafter, the present invention will be described in detail with reference to the following examples. However, the embodiments according to the present invention can be modified in various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. Embodiments of the present invention are provided to provide a more complete understanding of the present invention to those skilled in the art.

[Example 1]

Polytetrafluoroethylene (PTFE) Membrane Substrate To introduce the furan functionality onto the substrate surface, the polytetrafluoroethylene (PTFE) membrane substrate was first exposed to hydrazine vapor and ultraviolet light of 264 nm was applied for 48 hours at an output of 100 W To obtain a polytetrafluoroethylene (PTFE) membrane substrate modified with an amine group.

Thereafter, a polytetrafluoroethylene (PTFE) membrane base material modified with an amine group was impregnated into a solution of furfuryl glycidyl ether, and then reacted at 60 ° C. to finally obtain a polytetrafluoroethylene (PTFE) membrane substrate .

At this time, it was confirmed that 2.5 parts by weight of the furan functional group was introduced into 100 parts by weight of the polytetrafluoroethylene (PTFE) membrane base material modified with amine groups through XPS surface oxygen atom ratio analysis.

Polyethylene glycol (PEG) -maleimide was dissolved in a toluene organic solvent at a concentration of 5%. This solution was impregnated with a polytetrafluoroethylene (PTFE) membrane substrate modified with a furan group, and then hydrophilic PEG was introduced into polytetrafluoroethylene (PTFE) through a Diels-Alder reaction between furan and maleimide at 60 ° C to obtain PEG -coupled-PTFE (PEG-PTFE) membranes.

The prepared PEG-coupled-PTFE (PEG-PTFE) membrane was prepared by mixing 10 parts by weight of polyethylene glycol (PEG) -maleimide (maleimide) based on 100 parts by weight of a polytetrafluoroethylene (PTFE) .

Performance evaluation

Evaluation of regeneration ability of membrane

The separation membrane prepared in Example 1 was impregnated with a toluene solvent, and the PEG layer adhered to the surface of the separation membrane was removed by proceeding with the reverse reaction of the Deels-Eldder at 150 ° C. The Diels-Alder reaction was carried out in the same manner as in Example 1 to introduce a hydrophilic PEG layer into the PTFE separation membrane where the PEG layer was desorbed, thereby preparing a PEG-surface separation membrane. The surface adhesion and desorption of PTFE membrane on PEG were repeated three times to confirm reproducibility.

FIG. 2 is an FE-SEM photograph showing the PEG attachment and desorption process of the separation membrane prepared in Example 1. FIG. 2 (a), (d), (b), (e) 2 (a), 2 (b) and 2 (c) are photographs of a state in which PEG is attached to the PTFE separation membrane once, twice and three times, (A), (d), (b), (e), (c), and (f) , And it can be seen that a part of the pores of the PTFE separation membrane is clogged when PEG is attached, and a polymer layer is formed on the surface. On the other hand, if the PEG layer is removed by the reverse reaction of Diels-Elder, the polymer layer on the pores and surface of the membrane can be seen to have disappeared.

Foul ring Abatement  evaluation

The pure water was permeated at 0.5 bar and the pure water permeability was measured for 30 minutes. Then, 500 ppm of silica suspension solution was permeated for 1 hour to foul the membrane prepared in Example 1, followed by back-washing at 1 bar for 3 minutes To remove particles adhering weakly to the surface of the membrane. The fouling tendency of the prepared membrane and the pure PTFE membrane were compared with each other three times. Finally, the fouled membranes were treated with retro Diels-Alder conditions and the pure water permeability was measured after regeneration of the PEG layer.

FIG. 3 is a graph showing the fouling reduction performance and the regeneration performance of Example 1. Referring to FIG. 3, the fouling reduction performance by the introduced PEG layer and about 80% of the inherent performance of the separation membrane during the regeneration of the PEG layer Recovery.

10: Membrane substrate
20: functional group derived from dienes or functional group derived from polyisocyanates
30: a functional group-containing substance derived from a pinion or a functional group-containing substance derived from a diene
40: diene-dithiane coupling reaction
100: Regenerable water treatment membrane

Claims (16)

A membrane substrate; And
A diene-dithiane coupling coupler introduced on at least one surface of the separator substrate,
The diene-dithiane coupling coupler is preferably a diene-
A diene-based functional group introduced on at least one surface of the separator substrate, and a functional group-containing substance derived from the polyene copolymer coupled with the functional group derived from the dienes, And a functional group-containing substance derived from a diene coupled with the functional group-derived functional group. The method according to claim 1,
Wherein the separation membrane substrate is formed of at least one of a polymer material, an inorganic material, and a metal material. 3. The method of claim 2,
The polymeric material may be selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polysulfone (PSF), polyethersulfone (PES), polyacrylonitrile PAN, Polycarbonate (PC), Polyethylene (PE), Polypropylene (PP), Polyvinyl Chloride (PVC), Cellulose and Cellulose Acetate Wherein the water-soluble organic solvent is at least one selected from the group consisting of: 3. The method of claim 2,
Wherein the inorganic material is at least one of aluminum oxide (Alumina), silicon oxide, and titanium oxide (Titania). 3. The method of claim 2,
Wherein the metal material is at least one of stainless steel and palladium alloy. The method according to claim 1,
Wherein the diene comprises at least one selected from the group consisting of Butadiene, Cyclopentadiene, Pyrrole and Furan. The method according to claim 1,
Wherein the polyimide comprises at least one selected from the group consisting of acrylonitrile, quinone, maleic anhydride and maleimide. The method according to claim 1,
Wherein the diene-containing functional group-containing substance is a substance into which a pendant functional group is introduced into at least one of the inorganic particles, the metal particles and the hydrophilic polymer. The method according to claim 1,
Wherein the functional group-containing substance derived from the polythiophene is a substance into which a pendant functional group is introduced into at least one of the inorganic particles, the metal particles and the hydrophilic polymer. And introducing a diene-dithiocyanate coupling coupler on at least one surface of the separator. 11. The method of claim 10,
Wherein the step of introducing the diene-dithiane coupling coupler comprises:
Introducing a diene-based functional group onto at least one surface of the membrane substrate; And
And a step of coupling the functional group-derived functional group and the functional group-derived functional group-containing functional group-containing functional group-containing substance to the functional group-derived functional group-containing functional group-containing functional group-containing substance. 11. The method of claim 10,
Wherein the step of introducing the diene-dithiane coupling coupler comprises:
Introducing a functional group derived from a phosphorus-based material onto at least one surface of the separator base material; And
And adding a functional group-containing substance derived from a diene to the functional group-derived functional group to couple the functional group-derived functional group to the functional group-derived functional group. 13. The method according to claim 11 or 12,
Wherein the step of coupling the functional group derived from the dienes with the functional group derived from the polyimide is carried out at a temperature of 20 to 70 ° C. Treating the water containing contaminants with the water treatment separator of any one of claims 1 to 9 to attach a contaminant to the diene-dithiane coupling coupler;
Treating the water-treated separation membrane by heat treatment to dissociate the coupling between the diene-derived functional group and the polyene-based functional group of the diene-dithiane coupling coupler to remove contaminants; And
Containing substance derived from a diene or a functional group-containing substance derived from a polyimide is added to the polyimide precursor, and the functional group-derived functional group and the polyimide-derived functional group are recombined. 15. The method of claim 14,
Wherein the temperature for heat-treating the water-treated separation membrane is 80 to 200 占 폚. 15. The method of claim 14,
Wherein the step of dissociating the coupling comprises a retro-Diels-Alder reaction.

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