KR20210023206A - Composition for interfacial polymerizing polyamide and method for manufacturing water-treatment membrane using same - Google Patents

Abstract

The present invention relates to a composition for interfacial polymerization of polyamide comprising: an amine compound; an amphiphilic polymer, to a production method of a water treatment separation membrane using the same, and to a water treatment separation membrane produced thereby. The composition for interfacial polymerization of polyamide has an effect of increasing salt removal rate and permeate flow rate.

Description

A composition for polyamide interfacial polymerization and a method of manufacturing a water treatment separation membrane using the same {COMPOSITION FOR INTERFACIAL POLYMERIZING POLYAMIDE AND METHOD FOR MANUFACTURING WATER-TREATMENT MEMBRANE USING SAME}

The present specification relates to a composition for polyamide interfacial polymerization and a method of manufacturing a water treatment separation membrane using the same.

The phenomenon that the solvent moves through the separation membrane from the solution with the low solute concentration to the high solution between the two solutions separated by the semi-permeable membrane is called the osmotic phenomenon, and the pressure acting on the solution side with the high solute concentration due to the movement of the solvent Is called osmotic pressure. However, when an external pressure higher than the osmotic pressure is applied, the solvent moves toward a solution with a low solute concentration, and this phenomenon is called reverse osmosis. Using the reverse osmosis principle, various salts or organic substances can be separated through a semi-permeable membrane using a pressure gradient as a driving force. Water treatment separation membranes using the reverse osmosis phenomenon are used to separate substances at the molecular level, remove salts from salt water or seawater, and supply water for household, construction, and industrial use.

As a representative example of such a water treatment separation membrane, a polyamide-based water treatment separation membrane may be mentioned, and the polyamide-based water treatment separation membrane is manufactured by forming a polyamide active layer on a microporous support, and more specifically, polysulfurization on a nonwoven fabric. A phone layer is formed to form a microporous support, and the microporous support is immersed in an aqueous solution of m-phenylenediamine (mPD) to form an mPD layer, which is again trimesoyl chloride (TMC). ) It is prepared by immersing in an organic solvent to contact the mPD layer with TMC for interfacial polymerization to form a polyamide layer.

In the water treatment separation membrane, the salt removal rate is used as an important index indicating the performance of the membrane.

Korean Patent Publication No. 10-1999-0019008

The present specification is to provide a composition for interfacial polymerization of polyamide and a method of manufacturing a water treatment separation membrane using the same.

An exemplary embodiment of the present specification

Amine compounds; And it provides a composition for polyamide interfacial polymerization comprising an amphiphilic polymer.

In addition, an exemplary embodiment of the present specification

Preparing a porous layer; And

It provides a method for producing a water treatment separation membrane comprising the step of interfacial polymerization of the above-described polyamide interfacial polymerization composition and an acyl halide compound to form a polyamide active layer on the porous layer.

In addition, an exemplary embodiment of the present specification provides a water treatment separation membrane manufactured by the above-described manufacturing method.

In addition, an exemplary embodiment of the present specification provides a water treatment module including at least one water treatment separation membrane described above.

In the case of manufacturing a water treatment separation membrane using the composition for polyamide interfacial polymerization according to an exemplary embodiment of the present specification, when the amine compound penetrates into the organic solution layer in the interfacial polymerization process, the permeability of the interface increases, and accordingly, the dense polyamide Since the active layer can be prepared, there is an effect of improving the salt removal rate and the permeation flow rate.

1 shows a water treatment separation membrane according to an exemplary embodiment of the present specification.

Hereinafter, the present specification will be described in more detail.

In an exemplary embodiment of the present specification, the composition for interfacial polymerization of a polyamide is an amine compound; And an amphiphilic polymer.

The polyamide-based separation membrane can be prepared by interfacial polymerization of an amine compound and an acyl halide compound, and a water treatment separation membrane suitable for use can be obtained by controlling the ratio of the amine compound and the acyl halide compound.

Among the various uses of the water treatment separation membrane, the water treatment separation membrane for seawater desalination is mainly used in the Middle East, where water resources are scarce but adjacent to the sea. Since the water treatment separation membrane for seawater desalination must be able to purify seawater, which is a high concentration of saltwater, and maintain its performance even under high-temperature driving conditions, a high salt removal rate, permeation flow rate, and heat resistance are required.

The inventors of the present invention confirmed that when the composition for interfacial polymerization of polyamide contains an amphiphilic polymer, polymerization properties are improved at the interface between the aqueous solution layer and the organic solution layer. In particular, by introducing an amphiphilic polymer in the form of a vesicle, etc., deviating from the prior art of improving flow by forming a channel in a partial area inside the separator, it is not dependent on the durability of a specific channel, but is involved in the interfacial polymerization itself, It is characterized by enhancing the permeability of the amine compound into the organic solution layer and forming a more dense polyamide active layer. Moreover, in the case of a method in which a protein is used, such as introduction in the form of a vesicle, heat resistance and acid resistance are inevitably weak, but the water treatment separation membrane according to the present invention is preferable in terms of durability in that there is no such concern.

In the present specification, when a member is positioned'on' another member, this includes not only a case in which a member is in contact with another member, but also a case in which another member exists between the two members.

In the present specification, when a part'includes' a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

In the present specification, the amphiphilic polymer refers to a polymer including both a hydrophilic structure and a hydrophobic structure,

In the present specification,'hydrophilicity' means that the solubility parameter is 10 (cal/cm ³ ) ^1/2 or more, and the'hydrophobicity' means that the solubility parameter is less than ^{10 (cal/cm 3} ) ^1/2. The solubility parameter means a value measured by the HSP (Hansen solubility parameter) method.

In the exemplary embodiment of the present specification, the amphiphilic polymer is a block copolymer including a hydrophilic block and a hydrophobic block.

In the exemplary embodiment of the present specification, in the block copolymer, the hydrophilic block and the hydrophobic block are included in a molar ratio of 0.9:0.1 to 0.1:0.9.

In the exemplary embodiment of the present specification, the hydrophilic block includes one or more polymers selected from polyethylene oxide, polyvinyl alcohol, polyvinylpyrrolidone, and polyacrylic acid, and preferably includes polyethylene oxide.

In the exemplary embodiment of the present specification, the hydrophobic block includes one or more polymers selected from polypropylene oxide, polyvinyl acetate, polyvinylidene fluoride, and polytetrafluoroethylene, and preferably includes polypropylene oxide. do.

In one embodiment of the present specification, the amphiphilic polymer is a copolymer of polyethylene oxide and polypropylene oxide.

In an exemplary embodiment of the present specification, the amphiphilic polymer is represented by the following formula (1).

[Formula 1]

In Formula 1,

Wherein x is a mole fraction, 0 <x <1 is a real number,

Wherein y is a mole fraction, 0 <y <1 is a real number,

Wherein z is a mole fraction, 0 <z <1 is a real number,

x + y + z = 1.

In the exemplary embodiment of the present specification, x is 0.2 to 0.4.

In the exemplary embodiment of the present specification, y is 0.2 to 0.4.

In the exemplary embodiment of the present specification, z is 0.2 to 0.4.

In the exemplary embodiment of the present specification, the amphiphilic polymer is Pluronic ® F127 (Sigma-Aldrich Co.), Pluronic ® F188 (Sigma-Aldrich Co.), Kolliphor ® P188 (Sigma-Aldrich Co.), and Kolliphor ® P407 It is at least one selected from (Sigma-Aldrich Co.), and is preferably Pluronic ® F127.

In the exemplary embodiment of the present specification, the weight average molecular weight of the amphiphilic polymer is 8,000g/mol to 15,000g/mol, preferably 11,000g/mol to 13,000g/mol.

In the exemplary embodiment of the present specification, the content of the amphiphilic polymer is 0.001wt% to 0.01wt%, preferably 0.002wt% to 0.008wt%, more preferably based on 100wt% of the polyamide interfacial polymerization composition. Is 0.003wt% to 0.007wt%.

When the amphiphilic polymer is contained in an amount of less than 0.001 wt%, there is a problem that the effect is insignificant because it hardly performs a role as an additive, and when it is included in an amount exceeding 0.01 wt%, a trade-off relationship occurs due to an increase in excessive salt removal rate. There is a concern that the permeate flow rate may decrease.

In the exemplary embodiment of the present specification, the amine compound is not limited as long as it can be used for polymerization of polyamide, but m-phenylenediamine (mPD), p-phenylenediamine (PPD), 1,3,6- It may be one or more selected from benzenetriamine (TAB), 4-chloro-1,3-phenylenediamine, 6-chloro-1,3-phenylenediamine, and 3-chloro-1,4-phenylenediamine, Preferably it may be m-phenylenediamine (mPD).

In the exemplary embodiment of the present specification, the content of the amine compound may be 0.1wt% to 20wt% based on 100wt% of the polyamide interfacial polymerization composition, preferably 1wt% to 15wt%, more preferably It may be 3wt% to 10wt%.

When the content of the amine compound is in the above range, it is possible to prepare a uniform polyamide layer.

During the interfacial polymerization of the polyamide active layer, polyamide is rapidly formed at the interface between the aqueous solution layer and the organic solution layer.At this time, the surfactant makes the layer thin and uniform so that the amine compound present in the aqueous solution layer easily moves to the organic solution layer. A uniform polyamide active layer is formed.

In the exemplary embodiment of the present specification, the surfactant may be selected from nonionic, cationic, anionic and amphoteric surfactants. According to an exemplary embodiment of the present specification, the surfactant is sodium lauryl sulfate (SLS); Alkyl ether sulfates; Alkyl sulfates; Olefin sulfonates; Alkyl ether carboxylates; Sulfosuccinates; Aromatic sulfonates; Octylphenol ethoxylates; Ethoxylated nonylphenols; Alkyl poly(ethylene oxide); Copolymers of poly(ethylene oxide) and poly(propylene oxide); Alkyl polyglucosides such as octyl glucoside and decyl maltoside; Fatty acid alcohols such as cetyl alcohol, oleyl alcohol, cocamide MEA, cocamide DEA, alkyl hydroxyethyl dimethyl ammonium chloride, cetyltrimethyl ammonium bromide, cetyltrimethyl ammonium chloride, hexadecyltrimethylammonium bromide, and hexadecyltrimethylammonium chloride; And alkyl betaines. Specifically, the surfactant may be SLS, octylphenol ethoxylates, or ethoxylated nonylphenols.

In particular, when sodium lauryl sulfate (SLS) is used as the surfactant, SLS has a high degree of affinity for water and oil (Hydrophile-Lipophile Balance, HLB), so it is well soluble in water, and the critical Michelle concentration (Critical Michelle Concentration) is high. , CMC) is also high, so even if an excessive amount is added, the formation of the polyamide active layer is not inhibited.

In the exemplary embodiment of the present specification, the content of the surfactant may be 0.01wt% to 1wt% based on 100wt% of the polyamide interfacial polymerization composition.

In the exemplary embodiment of the present specification, the composition for interfacial polymerization of the polyamide may include water as a solvent, and the remainder of the composition except for an amine compound and an amphiphilic polymer may be water.

An exemplary embodiment of the present specification is preparing a porous layer; And interfacial polymerization of the polyamide interfacial polymerization composition and an acyl halide compound to form a polyamide active layer on the porous layer.

In one embodiment of the present specification, the step of preparing the porous layer may be performed by coating a polymer material on the nonwoven fabric, and the type, thickness, and porosity of the nonwoven fabric may be variously changed as needed. In the present specification, the porous layer may serve as a support.

Examples of the polymer material include polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethylchloride and polyvinylidene fluoride. And the like may be used, but are not necessarily limited thereto.

In one embodiment of the present specification, the polymer material is polysulfone.

In the exemplary embodiment of the present specification, the forming of the polyamide active layer comprises: forming an aqueous solution layer including the polyamide interfacial polymerization composition on the porous layer; And contacting an organic solution including an acyl halide compound and an organic solvent on the aqueous solution layer.

When the aqueous layer containing the polyamide interfacial polymerization composition is contacted with the organic solution, the amine compound coated on the surface of the porous layer reacts with the acyl halide compound to produce polyamide by interfacial polymerization, and the microporous layer Is adsorbed on to form a thin film. The contact method may be a method such as immersion, spray, or coating.

In the exemplary embodiment of the present specification, a method of forming an aqueous solution layer including the polyamide interfacial polymerization composition on the porous layer is not particularly limited, and any method capable of forming an aqueous solution layer on the porous layer is not limited. Can be used without. Specifically, spraying, application, immersion or dripping, etc. are mentioned.

In the exemplary embodiment of the present specification, the aqueous solution layer may be additionally subjected to a step of removing an aqueous solution containing an excess amine compound, if necessary. The aqueous solution layer formed on the porous support may be non-uniformly distributed when there are too many aqueous solutions on the support, but when the aqueous solution is non-uniformly distributed, a non-uniform polyamide active layer may be formed by subsequent interfacial polymerization. . Therefore, it is preferable to remove the excess aqueous solution after forming the aqueous solution layer on the support. The removal of the excess aqueous solution is not particularly limited, but may be performed using, for example, a sponge, an air knife, blowing nitrogen gas, air drying, or a compression roll.

The acyl halide compound is not limited as long as it can be used for polymerization of polyamide, but an aromatic compound having two or three carboxylic acid halides, for example, trimesoyl chloride (TMC), isophthaloyl chloride, and At least one selected from terephthaloyl chloride may be preferably used, and more preferably, trimesoyl chloride (TMC) may be used.

In the exemplary embodiment of the present specification, it is preferable that the organic solvent does not participate in the interfacial polymerization reaction, and an aliphatic hydrocarbon solvent, for example, isoparaffinic, which is a mixture of alkanes and alkanes having 5 to 12 carbon atoms with freons. It may contain at least one selected from among solvents. Specifically, selected from hexane, heptane, octane, nonane, decane, undecan, dodecane, cyclohexane, IsoPar (Exxon), IsoPar-G (Exxon), ISOL-C (SK Chem) and ISOL-G (Exxon) One or more may be used, but is not limited thereto.

The content of the acyl halide compound may be 0.05wt% to 1wt%, preferably 0.08wt% to 0.8wt%, more preferably 0.08wt% to 0.6wt%, based on 100wt% of the organic solution.

When the content of the acyl halide compound is in the above range, it is possible to prepare a uniform polyamide layer.

An exemplary embodiment of the present specification provides a water treatment separation membrane manufactured by the above-described manufacturing method.

Each configuration of the water treatment separation membrane may refer to the description of the above-described polyamide interfacial polymerization composition and a method of manufacturing the water treatment separation membrane.

1 shows a water treatment separation membrane according to an exemplary embodiment of the present specification. Specifically, FIG. 1 shows a water treatment separation membrane in which a nonwoven fabric 100, a porous layer 200, and a polyamide active layer 300 are sequentially provided, and the raw water 400 containing impurities as the polyamide active layer 300 Is introduced, the purified water 500 is discharged through the nonwoven fabric 100, and the concentrated water 600 is discharged to the outside without passing through the polyamide active layer 300. However, the water treatment separation membrane according to the exemplary embodiment of the present specification is not limited to the structure of FIG. 1, and an additional configuration may be further included.

In the exemplary embodiment of the present specification, the water treatment separation membrane may be a micro filtration membrane, an ultra filtration membrane, a nano filtration membrane, or a reverse osmosis membrane, and specifically a reverse osmosis membrane. .

An exemplary embodiment of the present invention provides a water treatment module including at least one or more of the aforementioned water treatment separation membrane.

The specific type of the water treatment module is not particularly limited, and examples thereof include a plate & frame module, a tubular module, a Hollow & Fiber module, or a spiral wound module. In addition, as long as the water treatment module includes the water treatment separation membrane according to the exemplary embodiment of the present specification described above, other configurations and manufacturing methods are not particularly limited, and general means known in the art may be employed without limitation. have.

Meanwhile, since the water treatment module according to the exemplary embodiment of the present specification has excellent salt removal rate and permeation flow rate, it may be usefully used in various water treatment devices such as household/industrial water purification devices, sewage treatment devices, seawater desalination devices, and the like.

In the exemplary embodiment of the present specification, the water treatment module may be included in the seawater desalination apparatus. Since the seawater desalination device is mainly used to purify seawater, which is a high-concentration brine, in Middle East plants, it is not only operated under high temperature conditions, but also receives periodic acid/base washing because the quality of raw water is poor. Therefore, the water treatment module of the present invention having excellent heat resistance and acid resistance is suitable for use.

Hereinafter, examples will be described in detail to describe the present specification in detail. However, the embodiments according to the present specification may be modified in various forms, and the scope of the present specification is not construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely describe the present specification to those of ordinary skill in the art.

<Example: Preparation of water treatment separation membrane>

Comparative Example 1.

18wt% of polysulfone solid was added to DMF (N,N-dimethylformamide) solution and dissolved at 80°C to 85°C for 12 hours or longer to obtain a uniform liquid. This solution was cast to a thickness of 150 μm on a nonwoven fabric having a thickness of 95 μm to 100 μm made of polyester. Then, the cast nonwoven fabric was put in water to prepare a porous polysulfone support having a porosity of 70%.

For interfacial polymerization of a polyamide containing 8 wt% of m-phenylenediamine (mPD), 0.06 wt% of sodium lauryl sulfate (SLS) as a surfactant, and the remainder of water based on 100 wt% of the composition on the support The composition was applied to form an aqueous solution layer.

Subsequently, an organic solution containing 0.25 wt% of trimesoyl chloride (TMC) and 99.75 wt% of Isopar-G was applied on the aqueous layer to form an organic layer to perform interfacial polymerization to form a polyamide active layer to prepare a water treatment separation membrane. I did.

Example 1.

In Comparative Example 1, a water treatment separation membrane was prepared in the same manner as in Comparative Example 1 except that 0.005 wt% of Pluronic ® F127 (Sigma-Aldrich Co., Mw: 12,500 g/mol) was added to the polyamide interfacial polymerization composition. I did.

<Experimental Example: Performance evaluation of water treatment separation membrane>

In order to measure the salt removal rate and the permeate flow rate (GFD) of the water treatment separation membrane prepared according to the above Examples and Comparative Examples, a water treatment module including a flat plate type permeation cell, a high pressure pump, a storage tank and a cooling device was used. The planar transmission cell had an effective transmission area of 28 cm 2 in a cross-flow method. After the water treatment separation membrane was installed in the permeation cell, preliminary operation was sufficiently performed for about 1 hour using tertiary distilled water for stabilization of the evaluation equipment.

Thereafter, after confirming that the equipment has been stabilized by operating the equipment for about 1 hour at a flow rate of 800 psi and 4 L/min with a 32,000 ppm NaCl aqueous solution, the amount of water permeated at 25°C for 10 minutes was measured and the permeate flow rate (flux: gfd (gallon) /ft ² /day)) was calculated, and the salt concentration before and after permeation was analyzed using a conductivity meter to calculate the salt removal rate, and the results are shown in Table 1 below.

Types of amphiphilic polymers Content of amphiphilic polymer (wt%) Salt removal rate
(%) Permeate flow
(GFD) Comparative Example 1 - 0 99.83 11.93 Example 1 Pluronic ®F127 0.005 99.86 13.03

Looking at the results in Table 1, the water treatment separation membrane of Example 1 prepared by adding an amphiphilic polymer according to an exemplary embodiment of the present specification, when compared with the water treatment separation membrane of Comparative Example 1 to which an amphiphilic polymer was not added, It can be seen that both the salt removal rate and the permeate flow rate appear higher. That is, when a water treatment separation membrane is prepared using the polyamide interfacial polymerization composition according to an exemplary embodiment of the present specification, it has been proven that there is an effect of simultaneously improving the salt removal rate and the permeation flow rate.

100: non-woven
200: porous layer
300: polyamide active layer
400: raw water containing impurities
500: purified water
600: concentrated water

Claims (12)

Amine compounds; And polyamide interfacial polymerization composition comprising an amphiphilic polymer. The method according to claim 1,
The amphiphilic polymer is a polyamide interfacial polymerization composition that is a block copolymer comprising a hydrophilic block and a hydrophobic block. The method according to claim 1,
The hydrophilic block is polyethylene oxide, polyvinyl alcohol, polyvinylpyrrolidone, and polyamide interfacial polymerization composition comprising at least one polymer selected from polyacrylic acid. The method according to claim 1,
The hydrophobic block is polyamide interfacial polymerization composition comprising at least one polymer selected from polypropylene oxide, polyvinyl acetate, polyvinylidene fluoride and polytetrafluoroethylene. The method according to claim 1,
The content of the amphiphilic polymer is 0.001wt% to 0.01wt% based on 100wt% of the polyamide interfacial polymerization composition. The method according to claim 1,
The amine compound is m-phenylenediamine (mPD), p-phenylenediamine (PPD), 1,3,6-benzenetriamine (TAB), 4-chloro-1,3-phenylenediamine, 6-chloro -1,3-phenylenediamine and 3-chloro-1,4-phenylenediamine of one or more selected from the polyamide interfacial polymerization composition. The method according to claim 1,
The content of the amine compound is 0.1wt% to 20wt% based on 100wt% for the polyamide interfacial polymerization composition for polyamide interfacial polymerization. Preparing a porous layer; And
A method of manufacturing a water treatment separation membrane comprising the step of interfacial polymerization of the composition for interfacial polymerization of polyamide according to at least one of claims 1 to 7 and an acyl halide compound to form a polyamide active layer on the porous layer. The method of claim 8,
The acyl halide compound is one or more selected from trimesoyl chloride (TMC), isophthaloyl chloride, and terephthaloyl chloride. A water treatment separation membrane manufactured by the manufacturing method of claim 8. A water treatment module comprising at least one water treatment separation membrane according to claim 10. The method of claim 11,
Water treatment module included in the seawater desalination device.

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