KR100680111B1 - Polyamide reverse osmosis composite membrane and preparation method thereof - Google Patents

Abstract

An aqueous amine solution for forming an active layer of a polyamide reverse osmosis composite membrane, which can prepare a polyamide reverse osmosis composite membrane with improved water permeability by adding multiple quaternary amine salts comprising two or more quaternary amine salts formed on a hydrocarbon main chain to an aqueous amine solution of a primary tank as compared with a case of using a tertiary amine salt-containing monomer, a polyfunctional tertiary amine salt or a quaternary amine salt-containing monomer, and a preparation method of the polyamide reverse osmosis composite membrane using the solution are provided. An aqueous amine solution for forming an active layer of a polyamide reverse osmosis composite membrane comprises 0.1 to 20 wt.% of a reactive primary amine monomer, 0.1 to 20 wt.% of multiple quaternary amine salts, and 60 to 99.8 wt.% of water. The multiple quaternary amine salts are represented by a formula 4, wherein a, b, c, d, e, f, and g are each independently an integer of 1 or more as a repeating unit of -CH2-, n is an integer of 1 or more as a degree of polymerization, and wherein ammonium hydroxide in the multiple quaternary amine salts of the formula 4 can form multiple quaternary amine salts using ammonium nitrate, ammonium sulfate, ammonium carboxylate or ammonium sulfonate. A preparation method of a polyamide reverse osmosis composite membrane comprises contacting (a) an aqueous amine solution comprising 0.1 to 20 wt.% of a reactive primary amine monomer, 0.1 to 20 wt.% of multiple quaternary amine salts and 60 to 99.8 wt.% of water, and (b) an organic solution of an amine reactive compound comprising 0.01 to 10 wt.% of a polyfunctional acyl halide monomer that is an amine reactive compound with the surface of a porous support to form an active layer by an interfacial polymerization.

Description

POLYAMIDE REVERSE OSMOSIS COMPOSITE MEMBRANE AND PREPARATION METHOD THEREOF}

[Industrial use]

The present invention relates to a polyamide reverse osmosis composite membrane and a method for preparing the same, and more particularly, to a multi-quadrate amine salt composed of two or more quaternary amine salts in a hydrocarbon main chain. By using together with a tertiary amine monomer, the present invention relates to a polyamide reverse osmosis composite membrane having improved water permeability and salt rejection rate compared to the case of using various kinds of polyfunctional aromatic amine monomers.

[Prior art]

Water is an essential resource for all living things, including humans, along with air, and its quantity and quality have a great impact on the life of the earth as well as human beings. Moreover, given the fact that the utilization of water resources is getting wider and the importance of water resources is increasing due to the development of science and industry, securing high quality water resources is a very important problem in maintaining the life of the earth. At present, the world's water is suffering from a shortage of pollution and shortages, and its consumption continues to increase, making it more difficult to obtain practically available water resources. According to a UN study, 1.2 billion people, or about one-fifth of the world's population, are experiencing safe drinking water shortages, and twice as many as 2.4 billion people drink water without sewerage. Due to poor management of these water resources, more than 3 million people worldwide die every year from unsanitary water.

Meanwhile, seawater is reported to account for over 70% of the world's water. However, since seawater contains a large amount of impurities such as salt and various salts, seawater cannot be directly used for industrial water, agricultural water, household water, and the like. Therefore, in order to remove various salts from seawater or salt water, it is essential to desalination by removing impurities such as salts from sea water or salt water in order to use them for various purposes in real life, and reverse osmosis composite membrane is a key component in this desalination process. Used as

The general reverse osmosis composite membrane structure is composed of a thin active layer that determines the separation characteristics of the reverse osmosis composite membrane by using an interfacial polymerization method in which a reaction is performed by contacting different solutions containing reactive monomers on a porous support at an interface. In particular, the polyamide active layer is formed by interfacial polymerization of a polyfunctional amine monomer and a polyfunctional acyl halide monomer. A process for preparing such polyamide reverse osmosis composite membranes is described in US Pat. No. 4,277,344 to Cadotte, 1981. This patent describes the formation of an aromatic polyamide active layer by interfacial polymerization between a polyfunctional aromatic amine monomer having at least two primary amine groups and at least three acyl halide monomers having at least three acyl halide groups. The detailed method described in this patent discloses that the polysulfone support is immersed in an aqueous solution of 1,3-phenylene diamine (MPD), a primary amine monomer, and then present in excess of 1, Interfacial polymerization was carried out by removing the aqueous 3-phenylenediamine (MPD) and contacting with a freon solution in which trimesoyl chloride (TMC) was dissolved. At this time, the interfacial polymerization time was 10 seconds. After the completion of the interfacial polymerization, the reverse osmosis composite membrane was dried at room temperature. Kedoto's reverse osmosis composite membrane prepared by this method showed higher permeability and salt rejection performance compared to the permeation performance of the conventional reverse osmosis composite membrane, but thereafter, various methods were used to improve the permeability and salt rejection performance of the reverse osmosis composite membrane. Much research has been conducted to make this possible.

For example, in 1989 US Pat. No. 4,872,984, Tomasschke describes a monomer 3 formed by a polyfunctional aromatic amine monomer having at least two reactive primary amine groups, a monomeric tertiary amine, and a strong acid on a porous support. A reverse osmosis composite membrane is prepared by interfacial polymerization by contacting an aqueous solution including a tertiary amine salt compound with an organic solution containing an aromatic polyfunctional acyl halide compound at an interface, wherein the tertiary amine salt compound included in the aqueous solution is a monomer ( monomeric) tertiary amine salt, consisting of monomeric tertiary amine and monomeric tertiary amine salt or quaternary amine salt formed by strong acid alone. Among the amines used at this time, the monomer tertiary amines are trialkylamines such as trimethylamine, triethylamine, tripropylamine, N-alkylcycloaliphaticamines, 1-methylpiperidine, N, N-dialkylamines, and the like. N, N-dimethylethanolamine and the like were used as, N-dimethylethylamine, N, N-diethylmethylamine, N, N-dialkylethanolamine, and tetraalkylammonium hydroxides as tetraalkylammonium hydroxides. Methyl ammonium hydroxide, tetraethylammonium hydroxide, benzyltriethylammonium hydroxide, benzyltriethylammonium hydroxide, benzine tripropyl hydroxide, a mixture thereof, and the like were used. Chemical structures of (1) monomeric tertiary amine salts and (2) quaternary amine salts presented in the Tomasuke patent are in the following formulas (1) and (2).

[Formula 1]

[Formula 2]

(In Formulas 1 and 2, R1 to R4 represent the same or different hydrocarbons, HX represents a strong acid, wherein X represents a halide nitrate, phosphate, sulfonate, carboxylate, halogenated carboxylate and oxidized halo acid. Means a substance consisting of a derivative.)

As another example, in 1996 US Patent No. 5,576,057 Hirose (Hirose) proposed a patent that can improve the flow rate of the membrane by adding 10 to 50% by weight of alcohol to the amine aqueous solution in preparing the reverse osmosis composite membrane. The alcohol used at this time is ethanol, propanol, butanol, butyl alcohol, 1-pentanol, 2-pentanol, isobutyl alcohol, isopropyl alcohol, 2-ethylbutanol, 2-ethylhexanol, octanol, cyclohexanol, tetra Hydroperfuryl alcohol, neopentyl glycol, t-butanol, benzyl alcohol, 4-methyl-2-pentanol, 3-methyl-2-butanol, pentyl alcohol, aryl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, Tetraethylene glycol, propanediol, butanediol, pentanediol, hexanediol, glycerol or mixtures thereof and the like are preferred. However, in preparing the reverse osmosis composite membrane by adding alcohol to the aqueous primary amine solution, the solubility difference between the primary amine aqueous solution and the secondary organic solution should be 7 to 15 (cal / cm ³ ) ^1/2 and 15 (cal / cm ³ ) If more than ^1/2 , the active layer is formed on the surface of the two solutions by the interfacial polymerization method, but the water permeability is reduced. The performance of the polyamide reverse osmosis composite membrane prepared by the above method showed a permeation rate of 29 to 42 [LMH] and a removal rate of 99.4 to 99.5%, so that no alcohol was added (25 [LMH] permeation rate and 99.6% removal rate). Water permeability is improved compared to the conventional polyamide reverse osmosis composite membrane performance, but the effect of adding a small amount of alcohol is insignificant, and when the excess alcohol is added, the primary amine aqueous solution and the secondary acyl halide organic Due to the difference in the solubility of the solution, the polymerization reaction did not proceed at the interface, resulting in a decrease in the salt excretion rate of the prepared polyamide reverse osmosis composite membrane.

As another example, in US Pat. No. 4,950,404, Chau prepared a reverse osmosis composite membrane by surface polymerization by adding a polar aprotic solvent to an amine aqueous solution and contacting with an organic solution containing a polyfunctional acyl halide. The polar aprotic solvent used was N-methylpyrrolidone, 2-pyrrolidone, N, N-dimethylformamide, dioxane, pyridine, lutidine, picoline, tetrahydrofuran, The sulfolane, sulfolene, hexamethylphosphoamide, triethyl phosphite, N, N-dimethylacetamide, N, N-dimethylpropionamide were said to be preferable.

Chau also used the reverse osmosis composite membrane prepared in U.S. Patent No. 4,983,291 to ascorbic acid, hydrochloric acid, citric acid, sulfamic acid, tartaric acid, ethylenediaminetetraace The post-treatment process step was carried out by contacting a solution containing an acid such as ethylenediaminetetraacetic acid, p-toluenesulfonic acid, L-lysine hydrochloride, and glycine. After the constant temperature (room temperature ~ 170 ℃) at a certain time (1 minute ~ 120 minutes) was proposed a method of drying. However, when the polyamide reverse osmosis composite membrane was added to have a high permeability, the salt excretion rate of the reverse osmosis composite membrane was relatively decreased as the composition ratio of the aprotic solvent was increased. In the case of reverse osmosis composite membrane, which was contacted with a solution containing acid after drying at 100 ° C, the performance of the membrane was minimal when a small amount of acid was added, and the permeability of the membrane was increased when the acid was added. As a result, the salt excretion rate was decreased. In addition, the water permeability of the reverse osmosis composite membrane after contact with the acid-containing solution through a drying step of 170 ℃ high temperature was shown to decrease.

As another example, in 2001 US Pat. No. 6,245,234, Ja-Young Koo describes a polyfunctional aromatic amine monomer having at least two reactive amine groups on a porous support, a strong acid and a polyfunctional tertiary amine, and a polar solvent. Was dissolved in an aqueous solution containing a polyfunctional acyl halide, a polyfunctional sulfonyl halide or a polyfunctional isocyanate at the interface of the porous support to prepare a reverse osmosis composite membrane by interfacial polymerization, wherein the polyfunctional 3 contained in the aqueous solution N, N, N ', N'-tetramethyl-1,6-hexanediamine, N, N, N', N'-tetramethyl-1,4-butanediamine, N, N, N ', N'-tetramethyl-2-butene-1,4-diamine, N, N, N ', N'-tetramethyl-1,3-butanediamine, N, N, N', N'-tetramethyl-1 , 3-propanediamine, N, N, N ', N'-tetramethyl-1,8-octanediamine, N, N, N', N'-tetramethyl-1,7-heptanediamine, N, N, N ', N'- Tramethyl-1,5-pentanediamine, N, N, N ', N'-tetraethyl-1,4-butanediamine, N, N, N', N'-tetraethyl-1,3-butanediamine, N, N, N ', N'-tetraethyl-1,3-propanediamine, 1,4-dimethylpiperazine, N, N, N', N'-tetraethylethylenediamine are preferred, where tertiary The molar ratio of amine and strong acid ranged from 1: 0 to 1: 1.

In addition, in 2002 U.S. Patent No. 6,368,507, Koo Ja-Young, in the preparation of reverse osmosis composite membrane, contains an amine aqueous solution containing a salt compound containing a polyfunctional aromatic primary amine monomer, a polar solvent, a polyfunctional tertiary amine salt and a tertiary amine. A method of preparing a reverse osmosis composite membrane by reaction with an organic solution containing a polyfunctional acyl halide, a polyfunctional sulfonyl halide or a polyfunctional isocyanate is provided. The molar ratio of the polyfunctional amine and the strong acid was suggested to be prepared in a range of 1: n at 1: 1 which is less than the number n of the amine groups of the polyfunctional tertiary amine. Chemical formula of the polyfunctional tertiary amine proposed in the Koo Ja Young patent is the same as the formula (3) below.

[Formula 3]

At this time, the polyfunctional tertiary amine consists of 2 to 10 carbon atoms of the alkane main chain, and the side chain of the alkane main chain is composed of at least two tertiary amines.

In addition, in 1998 US Patent No. 5,755,964, Michols (Mickols) is a hydride or an alkyl group substituted with ammonia having 1 to 3 alkyl groups of 1 to 2 carbon atoms in order to increase the permeability of the prepared reverse osmosis composite membrane A method of improving the permeation rate of the reverse osmosis composite membrane by 10% or more by contacting an aqueous amine solution substituted with oxy, phenyl or amino groups or a mixture thereof is proposed. At this time, it was found that trimethylamine, ethanolamine, ammonia, triethanolamine, dimethylamine, N, N-dimethylethanolamine, methylamine, and ethylenediamine are preferred as the amines used.

Summarizing the water permeability improvement method of the conventional polyamide reverse osmosis composite membranes examined so far, it is classified into two categories. First, a method of adding an additive such as an amine salt or alcohol to the primary bath, specifically, a method of adding a monomer tertiary amine salt or quaternary amine salt formed by monomeric tertiary amine and strong acid to the amine aqueous solution or main chain A polyfunctional tertiary amine consisting of two or more tertiary amine side chains in an alkan having 2 to 10 carbon atoms, a polyfunctional tertiary amine salt formed by a strong acid, and a polar solvent are added to the amine aqueous solution or a polar amount in the amine aqueous solution. It is a method of adding a magnetic solvent, alcohol, and the like. Secondly, as a method for post-treatment of the prepared reverse osmosis composite membrane, a method in which the surface of the prepared polyamide reverse osmosis composite membrane is contacted with an amine aqueous solution in which an alkyl group constituting a tertiary amine group is substituted with hydroxy, phenyl and amino groups. to be.

However, the two methods introduced so far have a structure in which monomer tertiary amine and monomeric tertiary amine salts or monomeric quaternary amine salts are independently used or two or more tertiary amines are used to improve the permeability of the membrane. The polyfunctional tertiary amine with polyacid and the polyfunctional tertiary amine salt by strong acid and polar solvent were used at the same time and alcohol was added as an additive to the aqueous solution of amine, which is the primary reaction tank, to prepare the reverse osmosis membrane, but the water permeability can be improved to the desired level. Was not.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to add various quaternary amine salts composed of two or more quaternary amine salts in a hydrocarbon main chain to a primary bath amine aqueous solution. Tertiary amines, i.e., monomeric tertiary amines or polyfunctional tertiary amines with improved water permeability compared to the use of monomeric tertiary amine salts, polyfunctional tertiary amine salts or monomeric quaternary amine salts alone It is to provide an amine aqueous solution for forming an active layer of a polyamide reverse osmosis composite membrane which enables the production of a polyamide reverse osmosis composite membrane.

It is also an object of the present invention to provide a method for producing a polyamide reverse osmosis composite membrane using the amine aqueous solution.

In order to achieve the above object, the present invention,

Formation of an active layer of a polyamide reverse osmosis composite membrane using an interfacial polymerization method with an aqueous solution of an amine containing 0.1-20% by weight of a reactive primary amine monomer, 0.1-20% by weight of a multi-quaternary amine salt and 60-99.8% by weight of water as a primary bath solution Aqueous amine solution is provided.

The present invention also provides

(a) an aqueous amine solution comprising 0.1 to 20% by weight of a reactive primary amine monomer, 0.1 to 20% by weight of multiple quaternary amine salts and 60 to 99.8% by weight of water; And (b) contacting the organic solution of the amine-reactive compound containing 0.01 to 10% by weight of the polyfunctional acyl halide monomer as the amine-reactive compound to the surface of the porous support to form an active layer by interfacial polymerization. Provided are membrane production methods.

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

The inventors of the present invention, in the known polyamide reverse osmosis composite membrane production method, when a multiquaternary amine salt, which has not been conventionally used as an additive, is added to the primary tank, the monomer is formed by monomeric tertiary amine or polyfunctional tertiary amine and strong acid. Alternatively, polyfunctional reverse osmosis composite membranes prepared by interfacial polymerization using polyfunctional tertiary amine salts or monomeric quaternary amine salts or using various organic solvents such as alcohols and polar solvents as additives can be prepared. By adding a quaternary amine salt alone, a method for preparing a reverse osmosis composite membrane having a polyamide active layer having an improved permeability while maintaining a relatively high salt rejection ratio compared to a conventional polyamide reverse osmosis composite membrane is disclosed. Came to complete.

The primary aqueous amine solution used to form the active layer of the polyamide reverse osmosis composite membrane of the present invention is a polyfunctional aromatic amine monomer is 1,4-phenylenediamine, 1,3-phenylenediamine (1, 3-phenylenediamine, 2,5-diaminotoluene, diphenyl diamine, 4-methoxy-m-phenylenediamine or mixtures thereof Preferably, the content is preferably 0.1 to 20% by weight, more preferably 0.5 to 5% by weight in the primary aqueous amine solution.

In addition, the primary aqueous amine solution of the present invention contains 0.1 to 20% by weight of multiple quaternary amine salts as essential components. If the content of the multi-quaternary amine salt in the primary aqueous amine solution is less than 0.1% by weight, the water permeability of the polyamide reverse osmosis composite membrane cannot be improved.On the contrary, if the content of the polyaluminum reverse osmosis composite membrane exceeds 20% by weight, the salt rejection ratio of the reverse osmosis composite membrane is Since it is rapidly reduced, it is not preferable as a method for producing a polyamide reverse osmosis composite membrane.

Examples of the multiple quaternary amine salts used in the primary aqueous amine solution are N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N ', N'-hexabutylhexamethylenediamino dihydroxide), N, N, N, N', N ', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N', N ', N' -hexamethylhexamethylenediamino dihydroxide), N, N, N, N ', N', N'-hexaethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexaethylhexamethylenediamino dihydroxide), N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide), or mixtures thereof Etc. are preferable, and the content is preferably 0.1 to 20% by weight, more preferably 1.0 to 10% by weight in the primary aqueous amine solution.

Multi quaternary amine salts presented in the present invention preferably has a structure of formula (4). As in Formula 4, the multiple quaternary amine salt of the present invention has the feature that two or more quaternary amines are composed in a main chain consisting of hydrocarbon.

[Formula 4]

(In Formula 4,

a, b, c, d, e, f and g are each independently a repeating unit of -CH ₂ -and an integer of 1 or more, and n is an integer of 1 or more as the degree of polymerization. In addition, the ammonium hydroxide (hydroxide) in the multiple quaternary amine salt of the formula (4) is ammonium nitrate (ammonium nitrate), ammonium sulfate (ammonium sulfate), ammonium carboxylate (ammonium carboxylate) or ammonium sulfonate (ammonim sulfonate) May form multiple quaternary amine salts.)

By adding a multi-quaternary amine salt of the above structure to the primary aqueous amine solution, the monomer tertiary amine salt with monomeric tertiary amine and strong acid or the polyfunctional tertiary amine salt or monomeric quaternary amine salt with polyfunctional tertiary amine and strong acid Compared to the water permeability improvement effect of the polyamide reverse osmosis composite membrane prepared by using a single compound alone, the composition of the multi-quaternary amine salt and the length and degree of polymerization of the hydrocarbon chain constituting the multi-quaternary amine salt alone By adjusting, the improved water permeability can be expected while maintaining the high salt rejection performance of the polyamide reverse osmosis composite membrane.

In addition, the polyfunctional acyl halide, which is an amine-reactive compound constituting the secondary organic solution that forms an interface on the surface of the primary aqueous amine solution and the polysulfone support, is trimesoyl chloride, terephthaloyl chloride. ), Isophthalolyl chloride or mixtures thereof, and the content thereof is preferably 0.01 to 10% by weight, more preferably 0.05 to 2.0% by weight in the secondary bath organic solution. Organic solvents include hexane, cyclohexane, heptane, alkane having 8 to 12 carbon atoms, halogen-substituted hydrocarbons of Freon, or a mixed organic solution thereof. As a prototype, Isopar C (Isopar C, Exxon) is preferred. Yes.

The method for forming a polyamide reverse osmosis composite membrane having excellent water permeability and salt excretion ratio of the present invention using the amine aqueous solution for forming an active layer of the polyamide reverse osmosis composite membrane of the present invention described above is a known polyamide reverse osmosis composite membrane production. In the process, an amine-reactive compound on the surface of a porous polysulfone support, using an amine aqueous solution comprising a composition ranging from 0.1 to 20% by weight of reactive primary amine monomer and 0.1 to 20% by weight of multiple quaternary amine salts as primary aqueous amine solution. It is characterized in that the polyamide active layer is formed in contact with the secondary organic solution. In addition, the drying step may be further carried out after interfacial polymerization.

The primary aqueous amine solution used to form the active layer of the polyamide reverse osmosis composite membrane of the present invention preferably comprises (a) 0.1 to 20% by weight of a reactive primary amine monomer and 0.1 to 20% by weight of a multi-quaternary amine salt.

In addition, it is preferable that the secondary organic solution which is interfacially polymerized with the amine aqueous solution to form the active layer of the polyamide reverse osmosis composite membrane contains 0.01 to 10.0% by weight of a polyfunctional acyl halide monomer which is an amine reactive compound.

The polyfunctional aromatic amine monomer is 1,4-phenylenediamine, 1,3-phenylenediamine, 1,3-phenylenediamine, 2,5-diaminotoluene ), Diphenyl diamine, 4- methoxy-m-phenylenediamine or a mixture thereof, and the like, and the content thereof is preferably 0.1 to 20% by weight in the primary aqueous amine solution. And 0.5 to 5% by weight is more preferable.

In addition, examples of the multi-quaternary amine salt used in the primary aqueous amine solution are N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ' , N ', N'-hexabutylhexamethylenediamino dihydroxide), N, N, N, N', N ', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N', N ', N '-hexamethylhexamethylenediamino dihydroxide), N, N, N, N', N ', N'-hexaethylhexamethylenediamino dihydroxide (N, N, N, N', N ', N'-hexaethylhexamethylenediamino dihydroxide) , N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide), or mixtures thereof Etc. are preferable, and the content is preferably 0.1 to 20% by weight, more preferably 1.0 to 10% by weight in the primary aqueous amine solution. If the content of the multi-quaternary amine salt in the primary aqueous amine solution is less than 0.1% by weight, the water permeability of the polyamide reverse osmosis composite membrane cannot be expected to increase, and if the content exceeds 20% by weight, the salt rejection ratio of the reverse osmosis composite membrane is decreased. Therefore, the polyamide reverse osmosis composite membrane production method is not preferable.

In addition, the polyfunctional acyl halide, which is an amine-reactive compound, which forms a secondary organic solution that interfacially polymerizes with the primary aqueous amine solution, is trimesoyl chloride, terephthaloyl chloride, and isophthalolyl chloride. chloride) or a mixture thereof, and the content thereof is preferably 0.01 to 10% by weight, more preferably 0.05 to 2.0% by weight in the secondary bath organic solution.

In addition, after performing the step of interfacial polymerization with the amine aqueous solution may be further carried out a step of drying for 10 seconds to 1 hour at 60 to 150 ℃.

Hereinafter, preferred examples and comparative examples of the present invention are described. The following examples and comparative examples are described for the purpose of more clearly expressing the present invention, but the contents of the present invention are not limited to the following examples and comparative examples.

1. Manufacture of polyamide reverse osmosis composite membrane

(Example 1)

After coating the polysulfone on the nonwoven fabric, the support layer prepared by the phase transfer method was prepared with 2.0% by weight of the reactive primary amine monomer 1,3-phenylenediamine (MPD) and 1.0% by weight of N, N. 1, containing N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide) It was immersed in the secondary amine aqueous solution for 1 minute. After removing the excess solution on the surface of the polysulfone support layer using a rubber roller, it was immersed for 10 seconds in an iso C (Isopar C, Exxon) organic solution containing 0.1% by weight of trimesoyl chloride (TMC) After drying at room temperature, a reverse osmosis composite membrane having a polyamide active layer was prepared by drying in an oven at 95 ° C. for 5 minutes.

(Examples 2 to 4)

N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N'), which is a multiple quaternary amine salt contained in the primary aqueous amine solution Polyamide reverse osmosis composite membrane was prepared in the same manner as in Example 1 except that the content of, N'-hexabutylhexamethylenediamino dihydroxide) was different from that of Example 1 depending on the range of 2.0 to 10% by weight. In each of Examples 2 to 4, N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'- The content of hexabutylhexamethylenediamino dihydroxide) is summarized in Table 1 below.

TABLE 1

division  Content (% by weight) Example 2 2.0 Example 3 5.0 Example 4 10.0

(Example 5)

Multiple quaternary amine salts contained in the primary aqueous amine solution, N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N' N, N, N, N ', N', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'- instead of, N'-hexabutylhexamethylenediamino dihydroxide) A polyamide reverse osmosis composite membrane was prepared by the same composition and preparation method as Example 1 except for using hexametylhexamethylenediamino dihydroxide.

(Examples 6 to 8)

N, N, N, N ', N', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N ', N'), which is a multiple quaternary amine salt contained in the primary aqueous amine solution Polyamide reverse osmosis composite membrane was prepared in the same manner as in Example 1 except that the content of, N'-hexametylhexamethylenediamino dihydroxide) was different from that of Example 1 depending on the range of 2.0 to 10% by weight. In each of Examples 6 to 8, N, N, N, N ', N', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'- The content of hexametylhexamethylenediamino dihydroxide) is summarized in Table 2 below.

TABLE 2

division  Content (% by weight) Example 6 2.0 Example 7 5.0 Example 8 10.0

(Examples 9-18)

The polyamide reverse osmosis composite membrane prepared in the same manner as in Example 1 was prepared according to the drying conditions as summarized in Table 3 below, that is, the drying temperature and drying time change. Drying conditions of Examples 9 to 18 are as shown in Table 3 below.

TABLE 3

division Drying temperature (℃) Drying time (minutes) Example 9 60 5 Example 10 70 5 Example 11 80 5 Example 12 90 5 Example 13 100 5 Example 14 95 One Example 15 95 3 Example 16 95 5 Example 17 95 7 Example 18 95 10

(Example 19)

N, N, N, N ', N', N'-hexaethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexaetylhexamethylenediamino dihydroxide) as a multiple quaternary amine salt A polyamide reverse osmosis composite membrane was prepared in the same manner as in Example 1 except for using.

(Example 20)

N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide) as a multiple quaternary amine salt A polyamide reverse osmosis composite membrane was prepared in the same manner as in Example 1 except for using.

(Comparative Example 1)

The polysulfone support was immersed in the amine aqueous solution containing 2.0 wt% MPD, and then the excess amine aqueous solution was removed from the surface of the support, followed by interfacial polymerization for 10 seconds on the surface with the Freon TF organic solution in which 0.1 wt% TMC was dissolved. To prepare a polyamide reverse osmosis composite membrane.

(Comparative Example 2)

The microporous polysulfone support was immersed in a primary aqueous amine solution containing 2.0 wt% MPD and 2.0 wt% tetramethylammonium hydroxide (TMAH) for 2 minutes, and then the excess amine solution was removed, followed by 0.05 A polyamide reverse osmosis composite membrane was prepared by contacting with a solution of Isopar (Exxon) in which wt% TMC and 0.075 wt% IPC were dissolved, followed by drying in an oven at 95 ° C. for 6 minutes.

(Comparative Example 3)

1.6 wt% MPD, 0.6 wt% N, N, N'N'-tetramethyl-1,6-hexanediamine (N, N, N'N'-tetramethyl-1,6-hexanediamine, TMHD) ), Immersed in an amine aqueous solution containing 0.06% by weight of toluenesulfonic acid (TSA) for 40 seconds, and then remove excess amine aqueous solution, and then dissolve 0.1% by weight of TMC in anisosof C (Isopar, Exxon) organic The polyamide reverse osmosis composite membrane was prepared by interfacial polymerization at the surface of the solution and the support.

(Comparative Example 4)

The porous polysulfone support was immersed in an amine aqueous solution containing 2.0 wt% MPD, 2.3 wt% CSA, 1.1 wt% TEA, 2.0 wt% dimethyl suloxide (DMSO) for 40 seconds, and then the excess amine aqueous solution was removed. After interfacial polymerization was carried out on the surface of the Isopar C (Exxon) organic solution in which 0.1 wt% TMC was dissolved, and dried at 95 ° C. for 3 minutes and 30 seconds to prepare a polyamide reverse osmosis composite membrane.

2. Measurement of Permeability and Salinity Rate of Polyamide Reverse Osmosis Composite Membranes

The water permeation rate and salt rejection rate of the polyamide reverse osmosis composite membranes prepared in Examples 1 to 20 and Comparative Examples 1 to 4 were measured under a pressure of 225 psi using a 2,000 ppm NaCl aqueous solution, and the results are shown in Table 4 below.

TABLE 4

division Permeability (L / m ² hr) Salt Exclusion Rate (%) Example 1 70.4 98.9 Example 2 72.5 97.7 Example 3 75.9 98.0 Example 4 88.8 93.2 Example 5 65.1 98.3 Example 6 69.2 96.8 Example 7 73.0 98.1 Example 8 82.3 93.8 Example 9 66.2 99.0 Example 10 70.4 98.2 Example 11 77.7 98.0 Example 12 69.6 99.1 Example 13 74.3 97.1 Example 14 73.2 96.9 Example 15 75.1 98.6 Example 16 76.8 97.5 Example 17 75.9 96.0 Example 18 77.6 95.9 Example 19 76.5 98.4 Example 20 80.1 96.8 Comparative Example 1 36.4 98.5 Comparative Example 2 34.1 99.7 Comparative Example 3 66.2 97.0 Comparative Example 4 62.9 99.0

As shown in Table 4 according to the above Examples and Comparative Examples, the polyamide reverse osmosis composite membrane of the present invention was found to have a high permeability of more than 70 L / m ² hr and far exceeding 90% salt rejection. Therefore, the polyamide reverse osmosis composite membrane of the present invention can be preferably used for membrane application conditions that require both permeability and high salt rejection rate.

As described above, the polyamide reverse osmosis composite membrane of the present invention uses multiple quaternary amine salts in the primary tank, thereby improving water permeability and salt rejection rate compared to the case where various types of polyfunctional aromatic amine monomers are used in the primary tank. It is possible to produce a polyamide reverse osmosis composite membrane having.

Claims (7)

Amine aqueous solution for forming an active layer of a polyamide reverse osmosis composite membrane comprising 0.1 to 20% by weight of a reactive primary amine monomer, 0.1 to 20% by weight of multiple quaternary amine salts and 60 to 99.8% by weight of water. The method of claim 1, The multi-quaternary amine salt is an amine aqueous solution for forming an active layer of the polyamide reverse osmosis composite membrane, characterized in that [Formula 4]

(In Formula 4, a, b, c, d, e, f and g are each independently a repeating unit of -CH ₂ -and an integer of 1 or more, and n is an integer of 1 or more as the degree of polymerization. In addition, the ammonium hydroxide (hydroxide) in the multiple quaternary amine salt of the formula (4) is ammonium nitrate (ammonium nitrate), ammonium sulfate (ammonium sulfate), ammonium carboxylate (ammonium carboxylate) or ammonium sulfonate (ammonim sulfonate) May form multiple quaternary amine salts.) The method of claim 1, The multiple quaternary amine salt, N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide), N, N, N , N ', N', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexamethylhexamethylenediamino dihydroxide), N, N, N, N ', N ', N'-hexaethylhexamethylenediamino dihydroxide (N, N, N, N', N ', N'-hexaethylhexamethylenediamino dihydroxide) and N, N, N, N', N ', N'- Amine aqueous solution for forming an active layer of a polyamide reverse osmosis composite membrane, characterized in that it is selected from the group consisting of hexapropylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide). In the method for producing a polyamide reverse osmosis composite membrane by interfacial polymerization of an amine aqueous solution and an amine reactive compound, (a) an aqueous amine solution comprising 0.1 to 20% by weight reactive primary amine monomer, 0.1 to 20% by weight multiple quaternary amine salt and 60 to 99.8% by weight water; And (b) a polyamide reverse osmosis composite membrane comprising forming an active layer by interfacial polymerization by contacting an organic solution of an amine reactive compound containing 0.01 to 10% by weight of a polyfunctional acyl halide monomer as an amine reactive compound with the porous support surface Manufacturing method. The method of claim 4, wherein The multi-quaternary amine salt is an amine aqueous solution for forming an active layer of the polyamide reverse osmosis composite membrane, characterized in that [Formula 4]

(In Formula 4, a, b, c, d, e, f and g are each independently a repeating unit of -CH ₂ -and an integer of 1 or more, and n is an integer of 1 or more as the degree of polymerization. In addition, the ammonium hydroxide (hydroxide) in the multiple quaternary amine salt of the formula (4) is ammonium nitrate (ammonium nitrate), ammonium sulfate (ammonium sulfate), ammonium carboxylate (ammonium carboxylate) or ammonium sulfonate (ammonim sulfonate) May form multiple quaternary amine salts.) The method of claim 4, wherein The multiple quaternary amine salt, N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexabutylhexamethylenediamino dihydroxide), N, N, N , N ', N', N'-hexamethylhexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexamethylhexamethylenediamino dihydroxide), N, N, N, N ', N ', N'-hexaethylhexamethylenediamino dihydroxide (N, N, N, N', N ', N'-hexaethylhexamethylenediamino dihydroxide) and N, N, N, N', N ', N'- Hexapropyl hexamethylenediamino dihydroxide (N, N, N, N ', N', N'-hexapropylhexamethylenediamino dihydroxide) polyamide reverse osmosis composite membrane manufacturing method characterized in that selected from the group consisting of. The method of claim 4, wherein Polyamide reverse osmosis composite membrane manufacturing method characterized in that for 10 seconds to 1 hour at 60 to 150 ℃ after the step (b).