KR101517653B1 - High Flux Reverse Osmosis Membrane Comprising Xanthene Compound And Manufacturing Method Thereof - Google Patents

Abstract

The present invention relates to a reverse osmosis membrane comprising a porous support comprising a polysulfone layer and a polyamide active layer formed on the porous support and comprising a xanthene compound and a method of producing the same, And a step of interfacially polymerizing an aqueous solution containing a xanthene compound and a polyfunctional acid halide compound solution on a support to form a polyamide active layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a high permeation flux reverse osmosis membrane containing a xanthene compound and a method for producing the same,

The present invention relates to a high permeation flow reverse osmosis membrane containing a xanthene-based compound and a method for producing the same.

In the process of separating the materials using the reverse osmosis phenomenon, the substances that are dissolved in the solution are separated from the solvent by selective membranes such as microfiltration, ultrafiltration and reverse osmosis membranes. The reverse osmosis membrane is a kind of semi-permeable membrane. When the solution is pressurized in one direction of an aqueous solution in which the salts are dissolved, the separation of the solution and the solute occurs in a certain direction, Has been used to desalinate industrial water, agricultural water, household water and the like in a relatively low amount of water with a relatively low salt content.

The conventional reverse osmosis membrane is composed of a porous support including a polysulfone layer and a polyamide active layer on the porous support, and a polyfunctional amine solution and an acid halide organic solution are interfacially polymerized on the porous support to form a polyamide active layer ≪ / RTI >

When the reverse osmosis membrane is used to pressurize an aqueous solution in which salt or ions are dissolved, the salt or ions in the aqueous solution can not pass through the membrane and are filtered and purified Water is the process of passing through the membrane. At this time, the applied pressure must be equal to or higher than the osmotic pressure of the aqueous solution, so that the higher the salinity of the aqueous solution, the greater the osmotic pressure and consequently the higher the pressure to be applied to the feed water, the more energy is consumed.

Therefore, the conditions to be provided for the reverse osmosis membrane for desalinating sea water and sea water containing a large amount of salt are not only excellent in the salt removing ability but also have a characteristic that a large amount of purified water can pass through the membrane even at a relatively low pressure, There must be a characteristic of overflow and flow rate.

Korean Patent Laid-Open Publication No. 2006-0065810 (published on Jun. 16, 2006) discloses a method for producing a reverse osmosis membrane of polyamide-based reverse osmosis membrane having a high salt removal rate characteristic without a large flow reduction compared to a conventional reverse osmosis membrane. In the production of a crosslinked polyamide reverse osmosis membrane obtained by dipping a substrate surface coated with a polyfunctional amine solution into a polyfunctional amine solution, removing the water layer on the surface by a pressing method and performing interfacial polymerization under an organic solution, And adding a step of immersing in distilled water containing a base for a predetermined time to swell the solution before immersion in a solution of a functional amine is added to the reverse osmosis membrane.

On the other hand, Korean Patent Laid-Open Publication No. 1999-0070132 (published on Sep. 15, 1999) discloses an invention that is characterized in carrying out an after-treatment process after interfacial polymerization, and inventions using a mixed organic solvent include Korea 1999-0070134 (published on September 15, 1999), and an invention disclosed in Korean Patent Laid-Open Publication No. 1999-0019008 (published on March 15, 1999) is characterized in that an additive is added to an organic solvent .

As described above, as the prior art, various inventions provide a reverse osmosis membrane production method and a reverse osmosis membrane using the same, wherein the salt removal ratio and the permeation flow rate are improved, but the porous support is further processed before immersing the membrane in the polyfunctional amine solution In the case of an invention in which a step of interfacial polymerization and post-treatment is carried out, the process is somewhat complicated and the cost is increased. Further, even in the case of using the mixed organic solvent or adding the additive to the organic solvent, there is a limit in improvement of the permeate flow rate and the salt removal rate of the produced reverse osmosis membrane.

Therefore, the applicant of the present invention invented the present invention as a result of repeated researches for inventing a reverse osmosis membrane having not only an improved permeation flow rate but also an increased salt removal rate through a more effective and simple method.

Korean Patent Publication No. 2006-0065810 (published on June 14, 2006) Korean Patent Publication No. 1999-0070132 (published on September 15, 1999) Korean Patent Publication No. 1999-0070134 (published on September 15, 1999) Korean Patent Publication No. 1999-0019008 (published on Mar. 15, 1999)

The present invention provides a reverse osmosis membrane having improved permeation flow rate and salt removal rate and a reverse osmosis membrane using the same.

One embodiment of the present invention provides a reverse osmosis membrane comprising a porous support comprising a polysulfone layer and a polyamide active layer formed on the porous support and comprising a xanthene-based compound.

The xanthene compound may be represented by the formula (1).

[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ), And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, a halogen group, or the like.

Wherein R ₁ and R ₂ may be each independently substituted amino or phenoxy group unsubstituted.

Two embodiments of the present invention are directed to a reverse osmosis membrane manufacturing method comprising forming a porous support, and interfacially polymerizing an aqueous solution containing a xanthene-based compound and a polyfunctional acid halide compound solution on the porous support to form a polyamide active layer .

The xanthene compound may be represented by the formula (1).

[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ), And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, a halogen group, or the like.

Wherein R ₁ and R ₂ may be each independently substituted amino or phenoxy group unsubstituted.

The xanthene-based compound may be contained in an amount of 0.01 to 10% by weight based on 100% by weight of the aqueous solution containing the xanthene-based compound.

Wherein the aqueous solution containing the xanthene compound is selected from the group consisting of m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3-phenylenediamine, 6- -1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine, and the like.

The reverse osmosis membrane of the present invention is characterized in that a reverse osmosis membrane having both improved salt removal rate and water permeability is formed by interfacial polymerization of an aqueous solution containing a xanthene compound and a polyfunctional acid halide solution at the time of forming a polyamide active layer on a porous support, Can be manufactured. In addition, the reverse osmosis membrane of the present invention comprising a polyamide active layer containing a xanthene-based compound may have good performance such as salt removal rate and water permeability.

The high permeation flow reverse osmosis membrane of the present invention provides a reverse osmosis membrane comprising a porous support containing a polysulfone layer and a polyamide active layer formed on the porous support and containing a xanthene compound.

The porous support may be formed by casting a polymeric material on a nonwoven fabric. As the nonwoven fabric material, for example, polyester, polycarbonate, microporous polypropylene, polyphenylene ether, polyvinylidene divinyl and the like may be used But is not limited thereto.

The thickness of the porous support may be 100 to 200 탆, may be 120 to 170 탆, and may be 140 to 150 탆. This is because if the thickness of the porous support is less than 100 탆, the reverse osmosis membrane is likely to be damaged because it can not withstand the pressure applied during the water treatment reverse osmosis membrane operation. If it is thicker than 200 탆, the surface roughness may become large, The performance of the membrane is likely to deteriorate because the pathway through which the water escapes is prolonged.

The pore size of the porous support is preferably 5 to 70 nm. This is because it is an effective range for selectively separating suspended substances, polysaccharides, proteins, and polymeric substances, which are generally known as substances capable of being separated from a porous support.

Examples of the polymeric material include polymeric materials such as polysulfone, polyethersulfone, polyethylene oxide, polyimide, polyamide, polyetherimide, polyetheretherketone, polyacrylonitrile, polymethylmethacrylate, polyethylene, poly Propylene, polymethylpentene, polymethyl chloride, and polyvinylidene fluoride may be used. In the present invention, polysulfone was used.

The polyamide active layer is formed on the porous support and performs the function of excluding the salt. Further, in the present invention, the polyamide active layer is characterized by containing a xanthene-based compound.

The xanthene compound may be represented by the formula (1).

[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ), And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, a halogen group, or the like.

Alternatively, the xanthene compound may be represented by the general formula (2).

(2)

In the above formula, the definitions of R ₁ , R ₂ and A are the same as above.

Alternatively, the xanthene compound may be represented by the following formula (3).

(3)

In the above formula, the definitions of R ₁ and R ₂ are the same as above.

More specifically, R ₁ and R ₂ may each be an amino-substituted or unsubstituted aminophenoxy group.

The present invention also provides a method for preparing a reverse osmosis membrane, comprising: forming a porous support; and interfacially polymerizing an aqueous solution containing a xanthene-based compound and a polyfunctional acid halide compound solution on the porous support to form a polyamide active layer do.

The step of forming the porous support is a step of casting a polymeric material on the nonwoven fabric, and the thickness, pore size, etc. of the nonwoven fabric, the polymeric material, and the porous support are as described above.

In the present invention, a conventional technique for producing a porous support can be used without limitation. For example, there are a stretching method in which a molten polymer is formed into a sheet, a lamella structure is formed by heat treatment, uniaxial stretching is carried out to separate the crystal interface, a polymer (polymer And a phase separation method in which a solvent is heated and melted to form a sheet, a micro phase is separated, and then the solvent is uniaxially or biaxially stretched while being extracted and removed.

On the other hand, the polyamide active layer is formed on the porous support and performs a function of excluding salts. The polyamide active layer is prepared by interfacial polymerization of an aqueous solution containing a xanthene compound and a polyfunctional acid halide compound solution on the porous support, Specifically, the step of forming the active layer may be carried out by, for example, immersing the porous support in an aqueous solution containing a xanthene-based compound, then interfacially polymerizing the polyfunctional acid halide compound solution to form an excess aqueous solution on the porous support Removing and drying the porous support to form an active layer on the porous support.

The xanthene compound may be represented by the formula (1).

[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ), And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, a halogen group, or the like.

Alternatively, the xanthene compound may be represented by the general formula (2).

(2)

In the above formula, the definitions of R ₁ , R ₂ and A are the same as above.

Alternatively, the xanthene compound may be represented by the following formula (3).

(3)

In the above formula, the definitions of R ₁ and R ₂ are the same as above.

More specifically, R ₁ and R ₂ may each independently be a substituted or unsubstituted aminophenoxy group.

The xanthene-based compound may be included in an amount of 0.01 to 10% by weight based on the total weight of the aqueous solution containing the xanthene-based compound. Or 0.05 to 7% by weight, or 0.1 to 5% by weight. If the xanthan-based compound is less than 0.01% by weight based on the total weight of the aqueous solution containing the xanthene-based compound, it is difficult to obtain the effect, while if it exceeds 10% by weight, it is difficult to effectively form pores for removing the salt to be.

Meanwhile, in the above-mentioned preparation method, the aqueous solution containing the xanthene-based compound may additionally include an amine compound, though not limited thereto. Examples of the aqueous solution containing the xanthene compound include m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3-phenylenediamine, 6- -1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine, and the like.

When the aqueous solution containing the xanthene compound additionally contains the amine compound, there may be differences in the pore size of the formed polyamide active layer, as compared with the case where the amine compound is added. Therefore, in order to control the pore size of the polyamide active layer to be obtained, it is possible to select whether the amine compound should be additionally added to an aqueous solution containing the xanthene compound, the type and content of the amine compound added, and the like In the present invention, the kind and content of the amine compound are not limited.

The polyfunctional acid halide solution is prepared by dissolving in an organic solvent at least one reaction material selected from the group consisting of a polyfunctional acyl halide, a polyfunctional sulfonyl halide, and a polyfunctional isocyanate. The polyfunctional acyl halide usable in the present invention may be at least one selected from the group consisting of trimesoyl chloride (TMC), isophthaloyl chloride (IPC) and terephthaloyl chloride (TPC).

Examples of the organic solvent include halogenated hydrocarbons such as Freon, aliphatic hydrocarbon solvents such as hexane, cyclohexane, heptane, and n-alkane having 8 to 12 carbon atoms. At this time, it is preferable that the aliphatic hydrocarbon solvent used is capable of dissolving at least 0.05% by weight of the polyfunctional acyl halide. For example, n-alkanes having 5 to 12 carbon atoms, mixtures of structural isomers of saturated or unsaturated hydrocarbons having 8 carbon atoms, cyclic hydrocarbons having 5 to 7 carbon atoms, or mixtures of two or more of the above solvents may be used.

Further, the step of forming the polyamide active layer may further include a washing step, and the washing liquid is preferably water. The washing time is not particularly limited, but is performed from 12 hours to 1 day or less. The polyamide active layer forming step may further include a step of drying in air. The drying time is not particularly limited, but is preferably 1 hour or less.

Hereinafter, the present invention will be described in more detail by way of examples.

Example  One

18% by weight polysulfone was added to N, N-dimethylformamide (N, N-dimethylformamide) and stirred at 80 DEG C for 12 hours or more to obtain 150 mu m polysulfone on the nonwoven fabric. The cast nonwoven fabric was immersed in water to prepare a porous support including a polysulfone layer. The prepared porous support was mixed with 1% by weight of 3 ', 6'-bis (4-aminophenoxy) -spiro (fluorene-9,9'-xanthene) spiro (fluorene-9,9'-xanthene), hereinafter referred to as 36B4AX), and then the excess aqueous solution on the porous support was removed using a pressing roller and dried at room temperature for 1 minute Respectively. Thereafter, the coated porous support was immersed in a solution of a polyfunctional acid halide compound containing 0.1% of trimethoyl chloride (hereinafter referred to as TMC) in a solvent of Isol C (SKC) Lt; RTI ID = 0.0 > 60 C < / RTI > for 10 minutes. The reverse osmosis membrane obtained by the above method was washed with a 0.2 wt% sodium carbonate aqueous solution at room temperature for 2 hours or more, and then rinsed with distilled water. A reverse osmosis membrane having a thickness of 180 탆 was prepared as described above.

Example  2

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 2% by weight.

Example  3

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 3 wt%.

Example  4

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 4 wt%.

Example  5

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 5 wt%.

Example  6

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 0.5 wt% and 2 wt% of m-phenylenediamine was added to the aqueous solution.

Example  7

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 1 wt% and 2 wt% of m-phenylenediamine was added to the aqueous solution.

Example  8

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that the concentration of 36B4AX was changed to 2 wt% and 2 wt% of m-phenylenediamine was added to the aqueous solution.

Comparative Example  One

A reverse osmosis membrane was prepared in the same manner as in Example 1, except that 2 wt% of m-phenylenediamine (hereinafter referred to as MPD) was added instead of 1 wt% of 36B4AX.

Experimental Example  One

The reverse osmosis membrane cell evaluation device is a Sepa CF II cell of GE Osmosis, which is composed of a planar permeation cell, a high-pressure pump, a storage tank, and a cooling device. The structure of the planar permeation cell is a cross- , And the effective permeation area is 140 cm ² .

After the washed membrane was installed in the permeable cell, the preliminary operation was performed for about 1 hour by using the third distilled water for stabilization of the evaluation equipment. Subsequently, the equipment was operated for about 1 hour until the pressure and water permeability reached a steady state by replacing with an aqueous solution of 32,000 ppm NaCl. After that, water permeated at 800 psi at a flow rate of 4500 ml / min at 25 ° C for 8 to 10 minutes And the water permeability was calculated. In addition, under the same conditions as described above, the removal rate was calculated by analyzing the salt concentration before and after the permeation using a conductivity meter. The results of the water permeability and the salt removal rate are shown in Table 1 below.

division Salt Removal Rate (%) Water Transmission (GFD) Example 1 (an aqueous solution containing 1% by weight of 36B4AX) 97.1 27.5 Example 2 (an aqueous solution containing 2% by weight of 36B4AX) 97.7 30.1 Example 3 (aqueous solution containing 3% by weight of 36B4AX) 98.1 31.2 Example 4 (an aqueous solution containing 4% by weight of 36B4AX) 97.9 28.2 Example 5 (an aqueous solution containing 5% by weight of 36B4AX) 97.9 23.5 Example 6 (an aqueous solution containing 0.5% by weight of 36B4AX and 2% by weight of m-phenylenediamine) 98.9 38.5 Example 7 (an aqueous solution containing 1% by weight of 36B4AX and 2% by weight of m-phenylenediamine) 99.3 39.8 Example 8 (an aqueous solution containing 2% by weight of 36B4AX and 2% by weight of m-phenylenediamine) 99.1 39.6 Comparative Example 1 (aqueous solution containing 2% by weight of m-phenylenediamine) 96.8 20.6

As shown in Table 1, when the aqueous solution containing a xanthene-based compound was used in the polyamide active layer formation step, the reverse osmosis membrane thus prepared exhibited improved performance in terms of salt removal rate and water permeability. Therefore, the reverse osmosis membrane according to the present invention is a reverse osmosis membrane containing a polyamide active layer containing a xanthene-based compound, and has a good salt removal rate and water permeability.

Comparing Examples 6 to 8 with Examples 1 to 5, when an aqueous solution containing a xanthene-based compound and an amine-based compound together is used in the polyamide active layer-forming step, an aqueous solution containing only a xanthene- The salt removal rate and the water permeability were increased more than those of the case of using. Therefore, even when an aqueous solution containing both a xanthene-based compound and an amine-based compound is used as well as an aqueous solution containing only a xanthene-based compound alone, both salt removal rate and water permeability can be improved, Was found.

Claims (8)

A porous support comprising a polysulfone layer; And
A polyamide active layer formed on the porous support and containing a xanthene compound,
Wherein the xanthene-based compound is represented by Chemical Formula (1).
[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ) And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, or a halogen group, respectively. delete The method according to claim 1,
Wherein R ₁ and R ₂ are each independently a substituted or unsubstituted aminophenoxy group. Forming a porous support; And
A step of interfacially polymerizing an aqueous solution containing a xanthene compound and a polyfunctional acid halide compound solution on the porous support to form a polyamide active layer,
Wherein the xanthene-based compound is represented by Chemical Formula (1).
[Chemical Formula 1]

Wherein R ₁ and R ₂ each independently represent an amino group, an aminoaryloxy group, an aminophenyl group, an aminophenoxy group, an aminophenol group, an aminophenoxy group, an aminocarboxyphenyl group, an aminocarboxyphenyloxy group, , An aminocarboxyphenol oxy group, an aminosulfophenyl group, an aminosulfophenyl group, an aminosulfophenol group, an aminosulfophenoloxy group, an aminoarylsulfinyl group, and an aminoarylsulfonyl group, A is any one selected from the group consisting of flu And examples thereof include fluorine, azulene, naphthalene, 1-methylnaphthalene, acenaphthene, acenaphthylene, anthracene, Phenalene, Phenanthrene, Benzo (a) fluorine, Chrysene, Fluoranthene, Pyrene, ) And tetracene (Tetracene), which may be substituted or unsubstituted with an alkyl group, a carboxy group, a hydroxy group, or a halogen group, respectively. delete The method of claim 4,
Wherein R ₁ and R ₂ are each independently substituted or unsubstituted aminophenoxy groups. The method of claim 4,
Wherein the xanthene-based compound is contained in an amount of 0.01 to 10 wt% based on 100 wt% of the aqueous solution containing the xanthene-based compound. The method of claim 4,
Wherein the aqueous solution containing the xanthene compound is selected from the group consisting of m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3- - phenylenediamine, and 3-chloro-1,4-phenylenediamine.