KR20160046068A - Modifying agent for biofouling-forward osmosis memebrane, Biofouling-forward osmosis memebrane and Manufacturing method thereof - Google Patents

Abstract

The present invention relates to a modifying agent for an antibiofouling-forward osmosis(FO) membrane, an antibiofouling-FO membrane, and a production method thereof. More specifically, the present invention is intended to increase a long-term life span stability of a membrane, by minimizing and/or preventing biofouling formed on a surface of an FO membrane after completely killing gram-positive and gram-negative bacterium.

Description

[0001] The present invention relates to an anti-biofouling-FO membrane modifier, an anti-biofouling-FO membrane, and a method for manufacturing the same. More particularly, the present invention relates to a biofouling-forward osmosis memebrane,

The present invention relates to an anti-biofouling-FO membrane modifier, an anti-biofouling-FO membrane produced therefrom, and a method of producing the same, which prevent microbial death and prevent and / To a FO film capable of reducing a ring.

Membrane filtration is a technique widely used in recent water treatment. Since the osmotic pressure which is formed naturally by the concentration difference is used as the osmosis (FO) among the membrane filtration methods, it is necessary to apply a water pressure higher than the osmotic pressure It has a relatively low energy compared with reverse osmosis (RO) and has the advantage of being able to treat feeds containing high concentration of solids because of the membrane contamination phenomenon.

Currently, it is widely applied to desalination, osmosis, sewage treatment, industrial wastewater treatment, etc. Biofouling, which is caused by the formation of biofilm by microorganisms and colloids on the surface of the osmosis membrane, Which is a major problem. Although chemical cleaning and backwashing have been carried out to reduce such biofouling, these methods are inevitable for temporary solutions and have a problem of damaging the membrane. Therefore, it is necessary to develop a novel FO membrane that can fundamentally block biofilm formation, which is the cause of biofouling.

The commercially available FO film is a cellulose triacetate film developed in HTO USA in the 1990s. There is a disadvantage that a polyester mesh having a membrane diameter of about 50 탆 and contained in a membrane and providing a mechanical strength may be decomposed by microorganisms, so that induction of solute in the reverse direction may occur, A non-cellulosic FO film having a ring characteristic has not yet been developed.

Quaternary ammonium is a compound (NR ^{4 +} ) in which four alkyl (or aryl) groups are bonded to a nitrogen atom charged with a monovalent cation. This material is known to have the property of destroying cell membranes such as bacteria, fungi, viruses, etc., and is being used as a disinfectant for various purposes due to these characteristics.

Further, a technique of introducing an organic polymer having a group having a positive charge into the skin layer of a reverse osmosis (RO) membrane is known in Japanese Patent Application Laid-Open No. 1997-024259 and disclosed in Japanese Patent Application Laid- However, in the case of a pure osmosis membrane (FO), a technique for effectively reducing biofouling is insufficient.

The present invention is intended to develop a membrane capable of reducing biofouling, which is one of the major problems in the water treatment operation using the positive osmotic pressure (FO), and the FO membrane that is currently being commercialized has a large number of biofouling, In particular, polyester meshes, which serve as a supporting layer of the FO film by microorganisms, are likely to be decomposed. Such problems are caused by the FO film effective for reducing biofouling through the surface modification of the FO film, and the FO film for modifying the FO film ≪ / RTI >

In order to solve the above-mentioned problems, the present invention is directed to an anti-biofouling-FO modifier comprising C1-C5 alcohol, acetic acid, a compound represented by the following formula (1) and water.

[Chemical Formula 1]

In Formula 1, R ¹ and R ² And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom.

As a preferred embodiment of the present invention, in the anti-biofouling-FO modifier of the present invention, R ¹ , R ² And R ³ are each independently a straight-chain alkyl group of C 1 to C ³ or a branched alkyl group of C 3 to C ⁵ , R ⁴ and R ⁵ are independently a C 1 to C 2 alkyl group, R ⁶ is a C 1 to C 20 linear alkyl group, And X is Cl or Br.

In one preferred embodiment of the present invention, the anti-biofouling-FO modifier of the present invention comprises 4 to 10 parts by volume of acetic acid, 1 to 5 parts by volume of the compound represented by the general formula (1) And 4 to 20 volume ratios.

In one preferred embodiment of the present invention, in the anti-biofouling-FO modifier of the present invention, the alcohol may include at least one selected from methanol, ethanol and propanol.

In one preferred embodiment of the present invention, the anti-biofouling-FO modifier of the present invention has a pH of 4.5-5.5.

Another aspect of the present invention relates to an anti-biofouling-FO membrane using the above-described anti-biofouling-FO modifier, characterized in that a compound represented by the following formula (2) is immobilized on the surface of the FO membrane.

(2)

In Formula 2, R < 2 ^> And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom.

As a preferred embodiment of the present invention, in the anti-biofouling-FO membrane of the present invention, the FO membrane may be a polyamide-based FO membrane.

In one preferred embodiment of the present invention, the FO film is a polyamide-based FO film containing a compound represented by the following general formula (3).

(3)

In Formula 3, n is a rational number satisfying the weight average molecular weight of the compound of 50,000 to 1,000,000.

In another preferred embodiment of the present invention, in the anti-biofouling-FO membrane of the present invention, the FO film to which the compound represented by Formula 2 is immobilized may include a compound represented by Formula 4 have.

[Chemical Formula 4]

In Formula 4, R < ^{2 >} And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom, and n is a rational number satisfying a weight average molecular weight of the compound of 120,000 to 4,500,000.

In another preferred embodiment of the present invention, the anti-biofouling-FO membrane of the present invention can be applied to a polymer membrane such as polysulfone polymer, polyamide polymer, polyimide polymer, polyester polymer, olefin polymer, polybenzimidazole polymer, And a porous support layer formed of a polymer including at least one selected from the group consisting of polyvinylidene fluoride and polyacrylonitrile.

In another preferred embodiment of the present invention, the anti-biofouling-FO membrane of the present invention may be a flat membrane or a hollow fiber membrane.

Another aspect of the present invention relates to a method for producing the above-described anti-biofouling-FO membrane, comprising the steps of: preparing a FO (Forward osmosis) membrane by coating on one side of a porous support with a polyamide- ; Plasma processing the FO film; A step of surface-modifying the plasma-treated FO film with the above-described anti-biofouling-FO modifier; And drying the surface-modified FO film to produce an anti-biofouling-FO membrane.

(3)

In the above formula (3), n is a rational number satisfying the weight average molecular weight of the compound represented by the general formula (3): 50,000 to 1,000,000.

In one preferred embodiment of the present invention, the FO film in the plasma processing step is a polyamide-based FO film.

As a preferred embodiment of the present invention, the plasma treatment may be performed under vacuum of 1 mTorr or less for 50 seconds to 1 minute and 30 seconds.

In one preferred embodiment of the present invention, the surface modification step may be performed by immersing the plasma-treated FO film in the anti-biofouling-FO modifier for 1 minute to 5 minutes.

In one preferred embodiment of the present invention, the drying step may be performed by drying the surface-modified FO film at 45 ° C to 70 ° C for 40 to 60 hours.

In one preferred embodiment of the present invention, the FO film in the plasma treatment step is a polyamide FO film containing a compound represented by the following formula (3), and the FO film subjected to the surface modification and drying step is represented by the following formula And the like.

 [Chemical Formula 4]

In Formula 4, R < ^{2 >} And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom, and n is a rational number satisfying the weight average molecular weight of the compound represented by the general formula (4): 120,000 to 4,500,000.

The FO membrane prepared by using the anti-biofouling-FO modifier of the present invention has an effect of killing both Gram-positive bacteria and Gram-negative bacteria, thereby reducing the formation of microbial membranes on the surface of the FO membrane. It is possible to reduce a lot of operating costs required for washing the membrane and chemical cleaning used for washing the membrane and to reduce the damage of the membrane as the membrane washing period becomes longer, So that the purchase cost can be saved.

Fig. 1 shows the results of FT-IR spectroscopy of the FO film of Comparative Example 1 performed in Experimental Example 1 and the anti-biofouling-FO film of Example 1. Fig.
2 shows the result of the microbial death test conducted in Experimental Example 2. Fig.
FIGS. 3 and 4 are confocal microscopic images of the results of microbial death tests conducted in Experimental Example 2, wherein FIG. 3 is an image for Comparative Example 1, and FIG. 4 is an image for Example 1.
5 and 6 are 3D images of the biofilm on the surface of the FO film of Comparative Example 1 and Example 1 performed in Experimental Example 3, respectively.

"로 표현된 화학식에서 "*" 표시는 치환기가 결합되는 부위, 다른 단량체와 중합되는 부위 또는 말단기가 결합되는 부위를 의미한다.
The term " C1 to C5 alkyl "means an alkyl group having 1 to 5 carbon atoms. In the present invention,"

Quot; in the chemical formula represented by "*" means a site to which a substituent is bonded, a site to be polymerized with another monomer, or a site to which a terminal group is bonded.

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

The anti-biofouling-FO modifier used in the production of the anti-biofouling-FO membrane of the present invention may include C1 to C5 alcohols, acetic acid, a compound represented by the following formula (1) and water.

[Chemical Formula 1]

In Formula 1, R ¹ and R ² And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C7 of C1 ~ C5, preferably R ^1, R ² And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C5 of C1 ~ C3, more preferably R ^1, R ² And R < ³ > are each independently a straight-chain alkyl group of C1-C2. In this case, R ¹ and R ² Or R ³ Is a straight chain alkyl group exceeding C5 or a crushing type alkyl group exceeding C8, the amount of the modifier component fixed to the FO film may be greatly reduced due to steric hindrance, so that an alkyl group having a carbon number within the above range is used It is good. Each of R ⁴ and R ⁵ is independently a C1-C3 alkyl group, preferably a C1-C2 alkyl group. The R ⁶ may be a straight chain alkyl group of C 15 to C 25, preferably a straight chain alkyl group of C ¹⁷ to C 20. When R ⁶ is a straight chain alkyl group of less than C 15, an anti-biofouling effect If R ⁶ exceeds C 25, there may be a problem that the carbon number is too large and the anti-fouling effect deteriorates due to steric hindrance. Therefore, it is advantageous to have the carbon number within the above range. In Formula 1, X is a halogen atom, preferably Cl or Br, more preferably Cl.

The alcohol, which is one of the components of the anti-biofouling-FO membrane modifier of the present invention, serves as a solvent. The alcohol may be a C1 to C5 alcohol, preferably selected from methanol, ethanol and propanol And more preferably one or more kinds of ethanol may be used.

The acetic acid, which is a component of the anti-biofouling-FO membrane modifier of the present invention, acts as a pH controlling agent. The amount of the acetic acid to be used is 4 to 10 parts by volume, preferably 4 to 8 parts by volume relative to 100 parts by volume of the alcohol If the amount of acetic acid is less than 4 parts by volume, there may be a problem that immobilization modification is delayed. If the amount of acetic acid is more than 10 parts by volume, Therefore, it is recommended to use within the above range.

In addition, the compound represented by Formula 1 as the anti-biofouling-FO modifying agent of the present invention is immobilized on the FO membrane, that is, it modifies the FO membrane to add microbial killing effect to the FO membrane. The amount of the compound represented by the formula (1) is preferably 1 to 5, preferably 1 to 4, more preferably 1.5 to 3.5, based on 100 parts by volume of the alcohol. Is less than 1 part by volume, the amount thereof used is too small to provide sufficient microbial killing effect to the FO film, and even if it is used in excess of 5 volume ratio, microbial killing effect of the FO film is not further increased, which is uneconomical.

Of the anti-biofouling-FO modifying agent of the present invention, the water serves to control the viscosity and pH of the modifier, and the amount thereof is 4 to 20 parts by volume, preferably 4 to 10 parts by volume per 100 parts by weight of the alcohol By volume, more preferably 4.5 to 8 by volume, is advantageous in terms of adjusting the viscosity of the modifier and adjusting the pH.

The anti-biofouling-FO modifying agent of the present invention having such a composition and composition ratio preferably has a pH of from 4 to 6, preferably from pH 4.5 to 5.5, and more preferably from about pH 4.7 to 5.3, wherein the pH of the modifier Is less than 4, there may be a problem that the immobilization is delayed, and if the pH exceeds 6, there is a problem that the immobilization is delayed likewise.

A method for producing an anti-biofouling-FO membrane using the above-described anti-biofouling-FO modifier of the present invention will be described below.

The anti-biofouling-FO membrane of the present invention is produced by coating a porous support with a polyamide resin represented by the following formula (3) to prepare a FO (Forward osmosis) membrane; Plasma processing the FO (Forward osmosis) membrane; Surface-modifying the plasma-treated FO film with an anti-biofouling-FO modifier; And a step of drying the FO film subjected to the surface modification treatment.

(3)

In the above formula (3), n may be a rational number satisfying the weight average molecular weight of the compound represented by the general formula (3) of 50,000 to 1,000,000, preferably a weight average molecular weight of 60,000 to 950,000. If the weight average molecular weight is less than 50,000, the mechanical strength of the anti-biofouling-FO film may be lowered. If the weight average molecular weight is more than 1,000,000, the mechanical strength is excellent, but the flexibility of the membrane itself may deteriorate, .

In the step of forming the FO film on one surface of the porous support, the porous support is prepared by using a polymer solution. In this case, the polymer compound forming the polymer solution is not particularly limited as long as it can form a normal osmosis membrane , A polymer having a weight average molecular weight in the range of 50,000 to 1,000,000 is preferably used in order to take the mechanical strength into account. Preferred examples thereof include polysulfone polymers, polyamide polymers, polyimide polymers, polyester polymers, olefins Based polymer, polybenzimidazole polymer, polyvinylidene fluoride or polyacrylonitrile, and the like. Examples of the polysulfone-based polymer include polysulfone, polyethersulfone, polyallyl ether sulfone, etc. Or copolymers or modifications of these polymers Or a mixture thereof.

The solvent used for the polymer solution for forming the porous support by doping on the fabric is a solvent which is polymerized at a temperature of from room temperature (25 ° C) to 150 ° C or less, (NMP), dimethylformamide (DMF), dimethylsulfoxide (DMSO), or dimethylacetamide (DMSO), and more preferably, (DMAc), or the like. In addition, the polymer solution may further include a hydrophilizing additive.

The FO film can be prepared by coating a polyamide resin containing the compound represented by the above formula (3) on one side of the prepared porous support by a coating method commonly used in the art. Upon formation of the polyamide layer, it is preferable to apply the polyamide-based resin on the porous support for 1 minute to 12 hours or less, or immerse the porous support in the polyamide-based resin. After that, the FO separation membrane can be produced by drying.

In addition, the step of plasma treatment may be a pretreatment for allowing the modifier component to react and fix well with the surface of the FO film, and the FO film in the plasma treatment step may include a polyamide-based FO film.

The step of performing the plasma treatment is advantageous in terms of preventing an unwanted reaction in a vacuum atmosphere of 1 mTorr or less, preferably 0.1 to 0.5 mTorr, more preferably 0.1 to 0.3 mTorr in a vacuum atmosphere . The plasma treatment is preferably performed in the vacuum atmosphere for 50 seconds to 1 minute and 30 seconds, preferably 50 seconds to 1 minute and 10 seconds.

In the production method of the present invention, the anti-biofouling-FO modifier of the step of modifying the surface is the one described above, and the plasma-treated FO film is immersed in the anti-biofouling-FO modifier for 1 minute to 5 minutes, Preferably 1 minute to 4 minutes, more preferably 2 minutes to 3 minutes to bond the FO film to the compound represented by Formula 1 of the modifier. When the surface modification step is performed as described above, it is fixed on the surface of the FO film in the form of a compound represented by the following formula (2).

(2)

In Formula 2, R < 2 ^> And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C7 of C1 ~ C5, preferably R ² And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C5 of C1 ~ C3, more preferably R ² And R < ³ > are each independently a straight-chain alkyl group of C1-C2. Each of R ⁴ and R ⁵ is independently a C1-C3 alkyl group, preferably a C1-C2 alkyl group. The R ⁶ may be a straight chain alkyl group of C 15 to C 25, preferably a straight chain alkyl group of C ¹⁷ to C 20. In Formula 2, X is a halogen atom, preferably Cl or Br, more preferably Cl.

The drying step may be performed by drying the surface modified FO film by performing the general drying method used in the related art. For example, the surface modified FO film is put into an oven, It can be dried at 70 ° C, preferably at 45 ° C to 60 ° C, for about 40 hours to 60 hours, preferably for about 45 to 50 hours.

When the plasma treatment, the surface modification treatment and the drying treatment are performed as described above, an FO film having the compound represented by the above formula (2) fixed on the surface of the FO film can be produced. As a preferable example, the compound represented by the above formula An antifoaming-FO film containing a compound represented by the following formula (4) can be produced.

[Chemical Formula 4]

In Formula 4, R < ^{2 >} And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C7 of C1 ~ C5, preferably R ² And R ³ each independently represent a straight chain alkyl group or branched alkyl group of C3 ~ C5 of C1 ~ C3, more preferably R ² And R < ³ > are each independently a straight-chain alkyl group of C1-C2. At this time, R ² Or R ³ Is a straight chain alkyl group exceeding C5 or a crushing type alkyl group exceeding C8, the amount of the modifier component fixed to the FO film may be greatly reduced due to steric hindrance, so that an alkyl group having a carbon number within the above range is used It is good. Each of R ⁴ and R ⁵ is independently a C1-C3 alkyl group, preferably a C1-C2 alkyl group. The R ⁶ may be a straight chain alkyl group of C 15 to C 25, preferably a straight chain alkyl group of C ¹⁷ to C 20. When R ⁶ is a straight chain alkyl group of less than C 15, an anti-biofouling effect If R ⁶ exceeds C 25, there may be a problem that the anti-Pauling effect is likewise deteriorated. Therefore, it is advantageous to have the carbon number within the above range. In Formula 4, X is a halogen atom, preferably Cl or Br, more preferably Cl. The n in Formula 4 is a rational number satisfying the weight average molecular weight of the compound of 120,000 to 4,500,000, preferably 120,030 to 4,000,000, and more preferably 120,030 to 2,700,000. When the weight average molecular weight is less than 120,000, the anti- There may be a problem that the mechanical strength of the RO membrane is lowered. If the weight average molecular weight exceeds 4,500,000, the flexibility of the membrane deteriorates and the long-term stability may be reduced. Therefore, the weight average molecular weight is preferably within the above range.

The anti-biofouling-WO membrane of the present invention can be prepared through the above-described anti-biofouling-FO modifier of the present invention and the above-mentioned production method.

In addition, the anti-biofouling-FO membrane of the present invention may be a flat membrane or a hollow fiber membrane.

The anti-biofouling-FO membrane of the present invention is an FO membrane on which the compound represented by the above-mentioned general formula (2) is immobilized on the surface of the FO membrane, preferably a FO membrane containing the compound represented by the general formula (4) Gram-negative bacteria can be killed, and the occurrence of biofouling on the FO membrane surface can be effectively prevented and / or reduced.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples should not be construed as limiting the scope of the present invention, and should be construed to facilitate understanding of the present invention.

[ Example ]

Comparative Example  One : FO Manufacture of membranes

380 parts by weight of N-methyl-2-pyrrolidone (NMP) was mixed with 100 parts by weight of a polysulfone resin having a weight average molecular weight of 76,500, followed by stirring. Next, as a hydrophilic additive, 100 parts by weight of the above polysulfone resin was added and stirred to prepare a polymer solution by adding 10 parts by weight of a hydrophilized polysulfone polymer.

Next, the polymer solution was applied to one side of the fabric (the fabric fibers were polyester-based, the fabric had 250-260 carpets, the fineness was 16-17 denier, and the average fabric thickness was 60 탆) A porous support having 105 to 110 mu m was prepared.

Next, a polyamide resin represented by the following Chemical Formula 3-1 was coated on one side of the porous support and then dried to form a polyamide layer having an average thickness of 200 nm to prepare a FO film.

 (3)

In Formula 3, n is a rational number satisfying the weight average molecular weight of the compound of 376,500 to 377,000.

Example  One : Anti-biofouling - FO Manufacture of membranes

The FO film of Comparative Example 1 was subjected to a plasma treatment for 60 seconds under a vacuum of 0.2 mTorr.

Next, 47.5 ml of ethanol, 2.5 ml of DI water (De-ionized water) and 2.5 ml of acetic acid were added to the vessel, 1.0 ml of the compound represented by the following formula (1-1) was added, The mixture was slowly stirred for 5 minutes to prepare a modifier. The pH of the modifier was 5.

Next, the FO film was surface-modified by immersing the plasma-treated FO film in the slowly stirring solution for 2 minutes, then taken out of the FO film, put in an oven, and dried at 50 ° C for 48 hours to obtain a compound represented by the following formula A fixed anti-biofouling-FO membrane was prepared.

[Formula 1-1]

In Formula 1-1, R ¹ , R ² , R ³ , R ^4, and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C 18, and X is a chlorine atom.

[Formula 4-1]

In the formula 4-1, R ² , R ³ , R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C 18, X is a chlorine atom, and n is a weight average molecular weight of the compound of 904, 904,680.

Example  2

An anti-biofouling-FO membrane was prepared in the same manner as in Example 1 except that an anti-biofouling-FO modifier comprising a compound represented by the following formula (1-2) was used instead of the compound represented by the above formula To prepare an anti-biofouling-FO membrane in which a compound represented by the following formula (4-2) was immobilized.

[Formula 1-2]

In Formula 1-2, R ¹ , R ^2, and R ³ are alkyl groups of C ² , R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C 18, and X is a chlorine atom.

[Formula 4-2]

In the formula 4-2, R ² , R ³ , R ^4, and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C 18, X is a chlorine atom, and n is a weight average molecular weight of the compound of 944, 944,950.

Example  3

An anti-biofouling-FO membrane was prepared in the same manner as in Example 1 except that an anti-biofouling-FO modifier containing a compound represented by the following formula (1-3) was used instead of the compound represented by the above formula To prepare an anti-biofouling-FO membrane in which the compound represented by the following formula (4-3) was immobilized.

[Formula 1-3]

In the general formula 1-3, R ¹ , R ² and R ³ are alkyl groups of C1, R ⁴ and R ⁵ are alkyl groups of C1, R ⁶ is a straight chain alkyl group of C ¹⁹ , and X is a chlorine atom.

[Formula 4-3]

Wherein R ² , R ³ , R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a linear alkyl group of C 18, X is a chlorine atom, and n is a weight average molecular weight of the compound of 910, 910 and 480, respectively.

Example  4

In preparation of the anti-biofouling-FO membrane modifier, 47.5 ml of ethanol, 2.5 ml of DI water (De-ionized water), 0.5 ml of acetic acid acetic acid, 1.0 ml of the compound represented by the following formula (1-1) was added, and the mixture was slowly stirred for 3 to 5 minutes to prepare a modifier. The pH of the modifier was 4.7.

Comparative Example  2

An anti-biofouling-FO membrane was prepared in the same manner as in Example 1 except that an anti-biofouling-FO modifier containing a compound represented by the following formula (1-4) was used instead of the compound represented by the above formula Thereby preparing an anti-biofouling-FO membrane in which the compound represented by the following chemical formula 4-4 was immobilized.

[Formula 1-4]

In Formula 1-4, R ¹ , R ^2, and R ³ are C1 alkyl groups, R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C26, and X is a chlorine atom.

[Formula 4-4]

Wherein R ² , R ³ , R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a linear alkyl group of C ²⁶ , X is a chlorine atom, and n is a weight average molecular weight of the compound of from 1,046 to 680, 1,046,750.

Comparative Example  3

An anti-biofouling-FO membrane was prepared in the same manner as in Example 1 except that an anti-biofouling-FO modifier comprising a compound represented by the following formula (1-5) was used instead of the compound represented by the above formula Thereby preparing an anti-biofouling-FO membrane in which the compound represented by the following formula 4-5 was immobilized.

[Formula 1-5]

In Formula 1-5, R ¹ , R ^2, and R ³ are alkyl groups of C1, R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C14, and X is a chlorine atom.

[Formula 4-5]

In the formula (4-5), R ² , R ³ , R ⁴ and R ⁵ are C1 alkyl groups, R ⁶ is a straight chain alkyl group of C 14, X is a chlorine atom, and n is a weight average molecular weight of the compound of 803, 804,100.

Comparative Example  4

In preparation of the anti-biofouling-FO membrane modifier, 47.5 ml of ethanol, 2.5 ml of DI water (De-ionized water), 0.5 ml of acetic acid acetic acid (6.4 ml), 1.0 ml of the compound represented by the following formula (1-1) was added, and the mixture was slowly stirred for 3 to 5 minutes to prepare a modifier. The pH of the modifier was 4.2.

Comparative Example  5

In preparation of the anti-biofouling-FO membrane modifier, 47.5 ml of ethanol, 2.5 ml of DI water (De-ionized water), 0.5 ml of acetic acid acetic acid, 1.0 ml of the compound represented by the following formula (1-1) was added thereto, and the mixture was slowly stirred for 3 to 5 minutes to prepare a modifier. The pH of the modifier was 5.8.

Experimental Example  One : FT - IR ( Fourier Transform Infrared Spectroscopy ) Measurement experiment

The FO film of Comparative Example 1 and the anti-biofouling-FO film prepared in Example 1 were subjected to FT-IR measurement, and the results are shown in FIG. At this time, the FT-IR measurement was performed using a Fourier infrared spectrometer (manufactured by Thermo (trade name: Nicolet 5700)).

Referring to FIG. 1, it can be seen that the surface of the FO film used in the experiment is composed of polyamide material through the presence of Amide I and Amide II peaks. In Comparative Example 1, there is an amide carbonyl group (1,671 cm ^-1 ) having a hydrogen bond in the Amide I region, whereas Example 1 is a carbonyl group (1,716 cm ^-1 ) , Which is interpreted as the combination of N and the modifier component by converting NH with hydrogen to C═O into N radical. Further, the compound represented by the formula 1-1 CH stretching peak (2,850 ~ 2,916 cm -1) that did not notice any FO membrane, which of 2,850 cm ^-1 and 2,916 cm ^-1 in the compound represented by the formula 1-1 From the measurement of the CH peak, it was confirmed that the immobilization reaction occurred in the compound component containing C ₁₈ H ₃₇ .

Experimental Example  2: Microbial death test ( bacteria viability test ) And Live / Dead kit  Test

(1) Microorganism preparation

Two microorganisms, Staphylococcus aureus strain ATCC6538 (S. aureus) and Escherichia coli strain K-12 (E. coli), which are Gram-negative bacteria, were tested for microbial killing and live / dead kit test .

Each microorganism was used in each experiment by incubating in 4 ml LB medium (LB broth) for 12 hours in a 37 ° shaking incubator. In the microbial death test, several times of washing with sterilized 0.9% NaCl was used to inhibit the growth of microorganisms. In biofilm experiments, the growth conditions were maintained using LB medium.

(2) Microbial death test

The E. coli and S. aureus were cultured in 4 ml of LB broth (LB Broth) for 12 hours in a shaking incubator at 37 ° C. , followed by centrifugation for 1 minute at 14,400 rpm for 3 minutes, pallet) was washed with sterile 0.9% NaCl four times. Next, the FO membrane of Comparative Example 1 and the anti-biofouling-FO membrane of Example 1 were cut into 2 squares of 1 cm x 1 cm using sterilized scissors, respectively, and then divided into four cuvettes.

Next, the prepared E. coli And S. aureus were diluted 1/10, 500 μl each was added to the cuvette containing the FO membrane, and the mixture was reacted for 3 hours while keeping the temperature at 37 ° C. under the fluorescent lamp. The colony count method was used for quantification of microorganisms. 100 쨉 l of the microbial cells of the reaction-cuvette were diluted to 1 x 10 < ~ ⁵ > by repeating 5 times 10 times with 900 쨉 l of sterilized 0.9% NaCl. Next, 100 μl of the diluted microorganism sample was spread on an LB broth agar plate (n = 5).

Next, the spreading plate was incubated in an incubator at 37 ° C for 12 hours (overnight incubation), and the number of microorganisms was counted by counting the number of the generated colonies. The results are shown in Tables 1 and 2 Respectively.

division
(Unit: cfu / ml) E. coli S. aureus Comparative Example 1 75.50 × 10 ⁶ 130.75 x 10 ⁶ Example 1 17.75 × 10 ⁶ 48.75 x 10 ⁶ Example 2 20.05 × 10 ⁶ 55.90 × 10 ⁶ Example 3 21.12 × 10 ⁶ 54.25 × 10 ⁶ Example 4 18.95 × 10 ⁶ 50.80 × 10 ⁶ Comparative Example 2 38.50 × 10 ⁶ 85.35 x 10 ⁶ Comparative Example 3 47.45 × 10 ⁶ 92.10 × 10 ⁶ Comparative Example 4 31.35 x 10 ⁶ 70.45 × 10 ⁶ Comparative Example 5 33.80 x 106 67.10 x 106

As shown in Table 1 and FIG. 2, the number of E. coli was determined to be 75.5 × 10 ⁶ cfu / ml in Comparative Example 1 and (17.75 to 21.12) × 10 ⁶ cfu / ml in the case of Examples 1 to 4, As a result, the E. coli reacted in Examples 1 to 4 , And in particular, Example 1 had the highest killing effect. In the case of S. aureus Comparative Example 1 130.75 × 10 ⁶ cfu / ml, Example 1 ^{(48.75 ~ 55.90) × 10 6} cfu / ml in Example 1 to conduct the reaction in Example 4 with S. aureus And more particularly, the killing effect of Example 1 was the most excellent. The student p value obtained from the t-test of the two experimental values was less than 0.05, and the number of repetition of the LB Agar Plate was 5 in the experiment. It is shown that QAC has a higher killing effect on Gram-negative bacteria ( E. coli ) because it showed 62% and 77% killing effect on S. aureus and E. coli , respectively.

Further, compared to the general formulas (1) and Comparative Example 3 was a case of less than 14 carbon atoms are straight-chain alkyl group of R ⁶ carbon atoms, a straight-chain alkyl groups was 25. Comparative Example 2 exceeded and R ⁶ in the formula (4) in Example 1, E. coli And the killing effect of S. aureus was drastically decreased. Thus, it was confirmed that R ⁶ had a significant effect of killing with an alkyl group having an appropriate carbon number.

Then, in Comparative Example 4 using an anti-biofouling-FO modifier prepared by adding more than 10 vol% of acetic acid to 100 parts by volume of alcohol, and using an anti-biofouling-FO modifier prepared by adding acetic acid to less than 4 parts by volume Compared with Example 1 and Example 4, the killing effect of E. coli and S. aureus was drastically lowered in Comparative Example 5 because the pH of the modifier was too low or too high to be immobilized on the FO membrane It is considered that the effect of the FO film is reduced.

(3) Live / Dead kit  Test

The cultured E. coli and S. aureus were reacted with the FO membrane of Comparative Example 1 and the anti-biofouling-FO membrane of Example 1, and then the reacted microorganism was diluted 1/10 times.

Next, 3 μl of each of the microorganisms was added with 3.34 mM SYTO ^® nucleic acid and 1 ml of Propidium iodide (LIVE / DEAD ^® BacLight ^™ Bacterial viability Kit) and stained in the dark for 15 minutes. After the dyeing was completed, the 0.2 μm filter was filtered and washed with 5 ml of sterilized DI. Then, the microbial cells were filtered and the microbial cells were fixed to a 0.2 μm filter by filtering twice the sterilized DI 5 ml.

The filtered microorganisms were measured using CLSM (Confocal Laser Scanning Microscopy, Carl Zeiss, LSM700), and the setting of the confocal scanning laser microscope was set as follows. 400 × magnification objective lens and EGTC (green) / PI (red) were used to measure live cells and dead cells. The mean number 4 and 4 Speed 4) and Zoom 2 ×, and the images were analyzed using Zen 2011 (Carl Zeiss). The results are shown in FIGS. 3 and 4.

In FIG. 3, most of the microorganisms are alive in the comparative example 1, so that the green color is seen and some microorganisms are dead. In contrast, in Example 1, most of the microorganisms die and appear red, and some microorganisms live in green The result shows that the anti-biofouling-FO membrane of the present invention has a killing effect on Gram-positive bacteria and Gram-negative bacteria.

Experimental Example  3: Biofilm  Test

(1) Microorganism preparation

Pseudomonas aeruginosa strain PA14 (Pseudomonas aeruginosa strain PA14) was used to confirm the biofilm inhibition effect.

 (2) DFR ( Drip flow reactor ) Biofilm  Test

Slide glass and Drip flow reactor (DFR) were thoroughly cleaned with alcohol and autoclaved to prevent microbial contamination during the biofilm test. The tube was pumped with ethanol After thorough washing, the cells were washed with sterile DI and used in the experiment.

PA14 was cultured in 2 ml of LB broth for 12 hours in a shaking incubator at 37 ° C and then 1 ml of the culture was added to 99 ml of LB medium at a ratio of 1/100 fresh culture to 12 And incubated overnight.

For the biofilm test, 100 ml of the cultured PA14 was subjected to 1/20 fresh culture in 1,900 ml of LB medium. Then, the FO film of Comparative Example 1 and the anti-biofouling-FO film of Example 1 were adhered to a sterilized slide glass, a slide glass was put in a DFR (Drip Flow Reactor), the pump was operated, And the reaction was allowed to proceed for 2 days to form a biofilm.

Next, the slide glass on which the biofilm was formed was taken out and washed twice with PBS (phosphate buffer saline) and DI water alternately.

ConA (1 占 퐂 / ml) was uniformly spread on a slide glass attached to the membrane and stained in a dark room for about 30 minutes.

Next, after washing again with PBS, 3D biofilm measurement images were measured using the Z-stack function of CLSM (Confocal Laser Scanning Microscopy, Carl Zeiss, LSM700). The results are shown in FIG. 5 (Comparative Example 1) and 6 (Example 1).

The biofilm formed in Example 1 of FIG. 6 shows a biofilm formed in a very flat shape with a thickness of about 20 μm. In Comparative Example 1 of FIG. 5, the thickness is 50 μm, which is 2.5 times And biofilms with high peaks up to 100 ㎛ were observed on the biofilm.

Therefore, although the biofilm of the FO membrane of Comparative Example 1 which was not modified with the modifier of the present invention was well formed, it was confirmed that the anti-biofouling-FO membrane of the present invention effectively inhibited biofilm formation.

The anti-biofouling-FO membrane modifier of the present invention and the anti-biofouling-FO membrane prepared using the same according to the above Examples and Experimental Examples were found to have the effect of killing both Gram-positive bacteria and Gram-negative bacteria, and , And the biofouling reduction effect was very large. The anti-biofouling-FO membrane of the present invention can be greatly reduced by the conventional method such as reverse osmosis and chemical cleaning used for conventional membrane cleaning, thereby reducing operating costs. Also, as the membrane cleaning cycle becomes longer, By minimizing the decomposition of the existing membrane support, it is expected that the membrane replacement cycle becomes longer and the membrane purchase cost can be reduced.

Claims (15)

An anti-biofouling-FO modifier comprising a C1-C5 alcohol, acetic acid, a compound represented by the following formula (1) and water;
[Chemical Formula 1]

In Formula 1, R ¹ and R ² And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom.
2. The compound according to claim 1, wherein R < 1 ^> , R < ^{2 >} And R ³ are each independently a straight-chain alkyl group of C 1 to C ³ or a branched alkyl group of C 3 to C ⁵ , R ⁴ and R ⁵ are independently a C 1 to C 2 alkyl group, R ⁶ is a C 1 to C 20 linear alkyl group, X is Cl or Br. ≪ RTI ID = 0.0 > 11. < / RTI >
The method according to claim 1, wherein the solution contains 4 to 10 parts by volume of acetic acid, 1 to 5 parts by volume of the compound represented by the formula (1), and 4 to 20 parts by volume of water, based on 100 parts by volume of the C1 to C5 alcohol. -FO membrane modifier.
The anti-biofouling-FO modifier according to claim 5, wherein the alcohol comprises at least one selected from the group consisting of methanol, ethanol and propanol.
The anti-biofouling-F0 modifier according to any one of claims 1 to 5, wherein the pH is 4.5 to 5.5.
An anti-biofouling-FO membrane in which a compound represented by the following formula (2) is immobilized on the FO membrane surface;
(2)

In Formula 2, R < 2 ^> And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom.
The anti-biofouling-FO membrane according to claim 6, wherein the FO film is a polyamide-based FO film.
The anti-biofouling-FO film according to claim 7, wherein the FO film is a polyamide-based FO film including a compound represented by the following formula (3):
(3)

In the above formula (3), n is a rational number satisfying the weight average molecular weight of the compound represented by the general formula (3): 50,000 to 1,000,000.
The anti-fouling-FO membrane according to claim 6, wherein the FO membrane to which the compound represented by the formula (2) is immobilized comprises a compound represented by the following formula (4):
[Chemical Formula 4]

In Formula 4, R < ^{2 >} And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom, and n is a rational number satisfying a weight average molecular weight of the compound of 120,000 to 4,500,000.
Coating the porous support with a polyamide resin represented by the following formula (3) to produce a FO film;
Plasma processing the FO (Forward osmosis) membrane;
Subjecting the plasma treated FO film to surface modification with the anti-biofouling-FO modifying agent of claim 6; And
Drying the FO film subjected to the surface modification treatment;
A method for producing an anti-biofouling-FO membrane;
(3)

In the above formula (3), n is a rational number satisfying the weight average molecular weight of the compound represented by the general formula (3): 50,000 to 1,000,000.
The method for producing an anti-biofouling-FO membrane according to claim 10, wherein the FO film in the step of plasma treatment is a polyamide-based FO film.
11. The method of claim 10, wherein the plasma treatment is performed under vacuum of 1 mTorr or less for 50 seconds to 1 minute and 30 seconds.
11. The method according to claim 10, wherein the surface modification step is performed by immersing the plasma-treated FO film in the anti-biofouling-FO modifier for 1 minute to 5 minutes.
The method according to claim 10, wherein the drying step comprises drying the surface-modified FO film at 45 ° C to 70 ° C for 40 hours to 60 hours.
The method according to claim 10, wherein the FO membrane subjected to the step of surface modification and drying comprises a compound represented by the following formula (4):
[Chemical Formula 4]

In Formula 4, R < ^{2 >} And R ³ are each independently a linear alkyl group of C 1 to C 5 or a branched alkyl group of C 3 to C 7, R ⁴ and R ⁵ are independently a C 1 to C 3 alkyl group, R ⁶ is a C 15 to C 25 linear alkyl group, X is a halogen atom, and n is a rational number satisfying the weight average molecular weight of the compound represented by the general formula (4) from 82,000 to 2,500,000.

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