KR100477592B1 - Composite polyamide reverse osmosis membrane and producing method of the same - Google Patents

Abstract

The present invention relates to a method for producing a reverse osmosis composite membrane used in a water purification device that can be used as industrial water, agricultural water, household water, etc., through salt removal of water such as salt water, salt water, and the like. The purpose of the present invention is to provide a reverse osmosis composite membrane having excellent salt rejection properties.

The present invention provides a polyfunctional amine, a compound containing a salt, an aqueous solution containing one or two or more polar compounds; The present invention relates to a polyamide reverse osmosis composite membrane obtained by interfacially reacting an organic solution (ii) comprising a polyfunctional acyl halide, a polyfunctional sulfonyl halide and an amine reactive reactant selected from a polyfunctional isocyanate, and a method of manufacturing the same. By using the process, reverse osmosis membranes are produced with high flow rates and good salt rejection even at low pressures.

Description

Composite polyamide reverse osmosis membrane and producing method of the same

The present invention relates to a novel reverse osmosis composite membrane used for desalination of a lot of water of low salinity such as industrial water, agricultural water, etc. through salt removal of water such as brine or seawater, and a method of manufacturing the same.

Dissociated materials can be separated from the solvent using several optional membranes, such as microfiltration membranes, ultrafiltration membranes and reverse osmosis membranes. Initially, reverse osmosis membranes used for brine and seawater desalination were useful for supplying large amounts of industrial and domestic water. The salt water and seawater desalination process using reverse osmosis membrane removes salts, ions and particles when only salt water is dissolved and dissociated ions and particles do not pass through the membrane and pure water passes through the membrane. As the osmotic pressure increases, at least 97% salt removal rate is required for the application of brine and seawater desalination, so the reverse osmosis membrane must have a high salt rate coefficient and also have the ability to pass relatively large amounts of water through the membrane at relatively low pressures. That is, they must have high flow characteristics. In general, the flux of the membrane is required for seawater desalination, 10 gallon / ft ² day (gfd) at 800 psi, and 220 gfd for brine. Depending on the application, the high flow rate is more important than the salt removal rate, or vice versa. .

The general type of reverse osmosis membrane consists of a porous support layer and a polyamide-based composite thin film on the support layer. Typical polyamide membranes can be obtained by interfacial polymerization of polyfunctional amines and polyfunctional acyl halides.

U.S. Patent 4,277,344, previously filed by Cadette, discloses aromatic polys obtained by interfacial polymerization of aromatic polyfunctional amines containing two primary amine substituents and aromatic acyl halides having three or more acyl halide functional groups. Techniques for amide thin films have been presented. Here, the reverse osmosis membrane is coated with methaphenylenediamine (m-phenylendiamine) on the microporous polysulfone support, and then the excess methaphenylenediamine solution is removed, and then trimezoyl chloride dissolved in Freon (trichlorotrifluoroethane) It is prepared by reacting with (TMC), wherein the contact time of interfacial polymerization is 10 seconds and the reaction proceeds in 1 second. Although Cadette's membrane shows excellent flow rate and salt removal rate, various studies have been conducted to increase the flow rate and increase the salt removal rate of the polyamide reverse osmosis composite membrane to provide an improved membrane. Improvements have been made, and most of the studies have been based on the use of various additives in solutions used in interfacial polymerization.

As an example, Tomashke's U.S. Patent 4,872,984 (registered in October 1989) (a) consists of an aromatic polyamine reactant and a monomer of essentially monomers having at least two or more amine functional groups to form a liquid layer on the microporous support layer. Applying the microporous support as an aqueous solution containing an amine salt; (b) the amine reactive reactant has, on average, at least about 2.2 acyl halides per molecule of the reactant and consists essentially of a polyfunctional acyl halide or mixture thereof A method of preparing a reverse osmosis membrane comprising contacting the liquid layer with an organic solvent solution of a phosphorus aromatic amine reactive reactant and (c) drying the product in two steps to form the permeable osmotic membrane.

The amine salts of Tomaski include trialkylamines such as trimethylamine, triethylamine and tripropylamine; N-alkylcyclic substituted amines such as 1-methylpiperidine; N, N-dimethylethylamine, N, N Dialkylethanolamines; mixtures of two cyclic tertiary amines, such as 3-quinuclidinol, or tetra, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and tetrapropyl ammonium hydroxide Alkyl ammonium hydroxide; Of benzyltrialkylammonium hydroxides such as benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, benzyltripropylammonium hydroxide and mixtures of at least one quaternary amine and strong acid selected from It is a water soluble salt.

In US Pat. No. 4,983,291, inventor Chau et al. Present a membrane prepared by interfacial polymerization on a porous support. According to this patent, the porous support is brought into contact with a polar aprotic solvent which does not react with an amine, an aqueous solution of polyamine containing a polyhydroxy substance and an acid acceptor, wherein the polyhydric substance is selected from ethylene glycol, propylene glycol, glycerin and As long carbon atoms containing glycols, the content of aqueous solution is from 0.1 to 50%. The excess solution of the coated support was removed and then contacted with the polyacyl halide organic solution, with sufficient time for the polymerization product to form on the support, the resulting complex being hydroxypolycarboxylic acid, polyaminoalkylene polycarboxyl After treatment with an acid, salt consisting of acid and amine, sulfuric acid, amino acid, amino acid salt, polymeric acid, organic acid and the like, it is dried to obtain a reverse osmosis composite membrane.

In addition, in the US patent 5,576,057, the inventor Hirose et al. (A) coating a solution (a) containing a compound having at least two amino groups on the porous support and then contacting the (b) solution containing a polyfunctional halogen acid reverse osmosis A method for preparing a permeable composite membrane was presented, wherein the difference in solubility constant between solution (a) and solution (b) was 7 to 15 (cal / cm 3) ^1/2 .

The solvent of the solution (A) is ethanol, propanol, butanol, 1-pentanol, t-amyl alcohol, isoamyl alcohol, isobutyl alcohol, isopropyl alcohol, undecanol, 2-ethylbutanol, 2-ethylhexanol, Octanol, cyclohexanol, tetrahydroperfuryl alcohol, neopentiglycol, t-butanol, benzyl alcohol, 4-methyl-2-pentanol, 3-methyl-2butanol, pentyl alcohol, allyl alcohol, ethylene glycol, di Mixtures of alcohol and water, such as ethylene glycol, triethylene glycol, tetraethylene glycol, propanediol, butanediol, pentanediol, hexanediol, glycerol, etc., nitromethane, formamide, methylformamide, acetonitrile, dimethylformamide, ethylform It is a mixture of nitrogen compounds such as amides and water. Here, Hirose et al. Note that the ratio of water / ethanol is selected in the range of 60 to 90/40 to 10 with respect to the ratio of (a) to water and other solutions.

And, in US Pat. No. 5,614,099, Hirose et al. Presented a reverse osmosis composite membrane in which the average surface roughness of the polyamide layer is at least 55 nm. Wherein the polyamide surface layer is prepared by reaction with a polyfunctional halogen acid compound having an amino group and a halogen acid group and the polymer film is a solution containing m-phenylenediamine in a porous polysulfone support such that a solution layer is formed on the support. After contact with, the film is prepared by placing the film in a dryer such that the trimezoyl chloride solution is contacted to form a polymer film on the support. The surface of the polyamide layer can be treated with a quaternary ammonium salt and coated with an organic crosslinked polymer having a positive charge. In addition, Hirose et al., Wherein multiple amino functional groups are present in the solution (a), and the use solution contains a specific alcohol, ether, ketone, ester, halogenated hydrocarbon compound, sulfur-containing compound, etc., and the water-soluble parameter is 8-14 (cal / Cm 3) is said to be excellent in the range ^1/2 .

Although the thin films obtained by the above method show a higher flow rate improvement than the conventional membranes, there is a need to improve the membranes with higher flow rates while maintaining a high salt rejection rate even at low pressures such as 120 psi.

The present invention has been made to solve the problems of the prior art as described above, in particular to provide a novel polyamide reverse osmosis composite membrane exhibiting high salt rejection and high flow characteristics even under low pressure.

The present invention is 0.3 to 12% by weight of a salt compound in 0.1 to 20% by weight of a multifunctional monomer amine having at least two or more amine functional groups; And 0.01-8% by weight of a polar solvent and a mixed solvent with water; 0.005-5% by weight of an amine-reactive compound selected from the group consisting of an aqueous solution containing a polyfunctional acyl halide, a polyfunctional sulfonyl halide, and a polyfunctional isocyanate The present invention relates to a polyamide membrane comprising a reaction product obtained by cross-linking an organic solution (ii) containing an organic solution on a porous support layer.

The present invention also provides a method for producing a polyamide membrane comprising the step of applying an aqueous solution (ⅰ) as described above on a porous support layer and contacting with the organic solution (ii) to obtain a reverse osmosis composite membrane cross-linked by interfacial polymerization. It is about.

Hereinafter, the present invention will be described in detail.

In the present invention, the compound containing a salt means a compound having at least one or more amine functional groups or amine complex salt functional groups, and particularly preferably a complex salt of a strong acid and a tertiary amine. Specific examples of strong acids include methanesulfonic acid, toluenesulfonic acid, kempsulfonic acid, ethanesulfonic acid, benzenesulfonic acid, nitric acid, hydrochloric acid, sulfuric acid, trifluoroacetic acid, and the like. 1,4-diazabicyclo [ 2,2,2] octane, 1,8-diazabicyclo [2,2,2] undel-7-ene, N, N, N ', N'-tetramethyl-1,3-butanediamine, N , N, N ', N'-tetramethyl-1,3-hexanediamine, N, N, N', N ', N "-pentanemethyl-1,3-butanediethylenetriamine, 1,1,3 , 3, -tetramethylguanidine, N, N, N ', N'-tetramethylethylenediamine, 1,2-dimethylimidazole substituted with imidazole functional groups, and mixtures thereof and the like can be used.

In addition, methylene glycol derivatives as polar solvents. Propylene glycol derivatives, 1,3-propanediolalkyl substituents, sulfone derivatives, nitrile derivatives, urea derivatives, and the like, specifically 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxy Alkoxyethanol such as ethanol, 1-pentanol, 1-butanol, di (ethylene glycol) t-butyl methyl ether, di (ethylene glycol) hexyl ether, propylene glycol butyl ether, propylene glycol propyl ether, 1,3-heptane diol , 2-ethyl-1,3-hexanediol, 1,3-hexanediol, 1,3-pentanediol, dimethyl sulfoxide, tetramethyl sulfoxide, butyl sulfoxide, methylphenyl sulfoxide, tetramethylene sulfone, butyl sulfone, Acetonitrile, propionnitrile, 1,3-dimethyl-2-imidazolidone, and the like. Such a polar solvent is preferably used so that the polar compound content of the mixed solvent is 0.01 to 8% by weight or less.

In the present invention, the salt compound is composed of a complex salt of a strong acid and a tertiary amine, and the tertiary amine is preferably a polyfunctional tertiary amine, wherein the polyfunctional tertiary amine is n tertiary amine functional groups (n is 2 It is preferable that the molar ratio of the reaction functional group of the polyfunctional tertiary amine and the strong acid is smaller than 1: n (preferably 1: (0.95) n).

In the present invention, the mixed solvent consists of a selective combination of water and one or more polar compounds, which combination of 2-ethyl-1,3-hexanediol, 2-ethyl-1,3-hexanediol and dimethylsulfoxide Mixtures, di (methylene glycol) hexyl ether, mixture of di (ethylene glycol) hexyl ether and dimethyl sulfoxide, propylene glycol, butyl ether, propylene glycol propyl ether, trimethylene glycol dimethyl ether, 1,3-dimethyl-2- Imidazolidinone, a mixture of 2-ethyl-1,3-hexanediol and acetonitrile, tetramethylene sulfoxide, butyl sulfoxide, methylphenyl sulfoxide, butyl sulfone, and the like, and a mixture thereof or a mixture thereof is used.

In addition, the mixed solvent is more specifically, a mixed solvent of alkoxyethanol and water, the content of the alkoxyethanol is about 0.05 to 4% by weight of the mixed solvent, dimethyl sulfoxide and water of the mixed solvent of dimethyl sulfoxide is The mixed solvent of about 0.01 to 8% by weight, the mixed solvent of alkoxyethanol and water is about 0.05 to 4% by weight of the mixed solvent and the mixed solvent of dimethyl sulfoxide and water. Mixed solution using a mixed solvent of about 0.01 to 8% by weight, mixed solvent of 1-pentanol and water, the content of 1-pentanol is about 0.01 to 2% by weight of mixed solvent, 1-butanol and water 1-butanol is a mixed solvent of about 0.01 to 3% by weight of mixed solvent, 1-pentanol is mixed solvent of water with 1-pentanol of about 0.01 to 2% by weight of mixed solvent, tetramethylene sulfone Tetramethylene sulfone is a mixed solvent of water and water of about 0.01 to 4 A mixed solvent, such as percent by weight is used.

Meanwhile, the present invention also discloses a method for preparing a polyamide reverse osmosis composite membrane comprising a step of applying an aqueous solution on a porous support followed by contact with an organic solution (ii) and drying. A method of coating an aqueous solution, firstly applying an aqueous solution containing a polyfunctional amine, a salt compound and a polar compound on a porous support as it is, and a second method containing only a salt compound and a polar compound on a porous support. Method of applying an aqueous solution containing polyfunctional amine again after applying the aqueous solution, and thirdly, an aqueous solution containing only a polar compound dissolved on the porous support, and then again containing an aqueous solution containing polyfunctional amine and a salt compound Methods of applying can be used.

The microporous support layer used in the present invention does not need to be very specific, but the porosity of the general polymer material is sufficient to allow the permeate to pass through, and the pore size should be sufficient so that the ultra-thin film is cross-linked. The pore size of the support layer is in the range of 1 to 500 nm, and when it exceeds 500 nm, the ultra-thin film is recessed between the pores to collapse the flat film state. Microporous support layers useful in the present invention include halogenated substituent polymers such as polysulfone, polyethersulfone, polyimide, polyacrylonitrile, polypropylene, and polyvinylidene fluoride.

In the present invention, the thickness of the microporous support layer is not very important, but generally 25 to 125 mu m (more preferably, 40 to 75 mu m) is preferred. The polyfunctional amines used in the present invention are amines of monomers having at least two or more amine functional groups, and more preferably 2-3 amine functional groups. The amines used in the present invention are not specific and consist of a single polyamine or combinations of single polyamines. Examples of suitable polyamines include metaphenylenediamine, paraphenylenediamine and substituted derivatives thereof, wherein the substituents include alkyl groups such as methyl and ethyl, ethoxy groups, hydroxyalkyl groups, hydroxy groups, or halogen atoms. Include. Another example of a suitable polyamine is 1,3-propanediamine, alkanediamine with N-alkyl or N-aryl substituents of 1,3-propanediamine, cycloaliphatic primary amines such as cyclhexanediamine, piperazine, pipepe Cycloaliphatic secondary diamines such as azine alkyl derivatives, aromatic secondary amines such as N, N'-dimethyl-1,3-phenylenediamine, N, N'-diphenylethylenediamine, benzidine, xylene diamine and the like Derivatives and the like.

An aqueous solution is prepared by mixing a water solvent and one or two polar compounds with an amount of polyamine capable of producing an aqueous polyamine solution in an amount of 0.1 to 20% by weight (more preferably 0.5 to 8.0% by weight). The resulting aqueous solution is in the range of pH 7-13, and the pH can be adjusted by containing 0.001-5% by weight of basic acid acceptor. Acid acceptors include hydroxides, carboxylates, carbonates, borates, phosphates of alkali metals, and trialkylamines.

As described above, the aqueous solution layer is a solution containing an amine salt. Herein, the amine salt more preferably has 3 to 4 alkyl, substituted group functional groups, benzyl, alkoxy, and alkanol functional substituents on the nitrogen atom. The amine salt is, of course, the product produced by the reaction of a quaternary ammonium salt or a strong acid with a tertiary amine.

Suitable compounds as quaternary ammonium salts of the invention include tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, tetramethylammonium hydroxide, tetrapropylammonium hydroxide, benzyltrimethylammonium hydroxide, benzyltrimethylammonium hydroxide Benzyltrialkylammonium hydroxides such as the hydroxide, benzyltrimethylammonium hydroxide or mixtures thereof are possible.

The amine salt here is a reactant of a strong acid with a tertiary amine consisting of a tertiary amine of a single functional group or a polyfunctional tertiary amine. Suitable single functional amines for the amines used in the present invention include trimethylamine, trimethylamine, trialkylamines such as tripropylamine, alkylcycloaliphatic amines such as 1-methylpiperidine, N, N'-dimethylethyl Amines, N, N'-diethylmethylamine, N, N'-dialkylethanolamines such as N, N'-dimethylethanolamine and the like.

The reaction molar ratio between the tertiary amine of the polyfunctional group and the strong acid is 1: 1 or more and 1: n or less, where n means that there are n tertiary amine functional groups in one molecule of the tertiary amine of the polyfunctional group ( U, S, S, N, followed the notation of 09 / 067,891). When the molar ratio of the tertiary amine of the polyfunctional group and the amine salt composed of strong acid is 1: 1 or more and 1: (0.90) n or less, the physical properties are improved. In particular, the reaction of the polyfunctional tertiary amine having a strong acid and the amine salt composed of strong acid The molar ratio is greater than 1: 1 and less than 1: (0.95) n.

More preferably, the amine salt consisting of a multifunctional tertiary amine and a strong acid coexists with at least one tertiary amine salt functional group and at least one tertiary amine together. Although not defined by a specific principle in the present invention, the effect of improving the flow rate by the tertiary amine salt functional group helps to form the polyamide pores, and the tertiary amine is a polyfunctional amine (metaphenylenediamine) and an amine reactive compound (trimezo It is inferred to have an effect of promoting the interfacial polymerization reaction by acting as an acid acceptor of the acid-by-product occurring in the interfacial polymerization of monochloride). This dual function is characterized by a significant flow rate improvement effect compared to the amine salt having only a tertiary amine salt functional group without a tertiary amine as a monomer.

Polyfunctional tertiary amines suitable for the present invention include 1,4-diazabicyclo [2,2,2] octane (DABCO). 1,8-diazabicyclo [5,4,0] untec-7-ene, N, N, N ', N'-tetramethyl-1,3-butanediamine (TMBO), N, N, N' , N'-tetramethyl-1,6-hexanediamine, N, N, N ', N', N "-pentanemethyl-1,3-butanediethylenetriamine, 1,1,3,3-tetramethyl Guanidine (TMGU), N, N, N ', N'-tetramethylethylenediamine (TMED), 1,2-dimethylimidazole (DMI) substituted with imidazole functional groups, 1-alkyl-imidazole substituents and the like Mixtures, etc. As for the amine salt used in the present invention, an aqueous solution of 0.3-12% (more preferably 0.6-8%) is preferred.

As mentioned above, the addition of the polyfunctional amine and the amine salt is made in an aqueous solution in which at least one polar solvent is added. Here, as the polar solvent, ethylene glycol derivatives, propylene glycol derivatives, 1,3-propanediol derivatives, alcohols, sulfoxide derivatives, sulfone derivatives, nitrile derivatives, urea derivatives, and mixtures thereof may be selected. Includes alkoxyethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, di (ethylene glycol) t-butylmethyl ether, di (ethylene glycol) hexyl ether Can be used

In the present invention, propylene glycol butyl ether, propylene glycol propyl ether may be used as the propylene glycol derivative, and 1-pentanol, 1-butanol, etc. may be used as the alcohol, and 1,3-propanediol derivative may be used. Heptanediol, 2-ethyl-1,3-hexanediol, 1,3-pentanediol may be used, and dimethyl sulfoxide, tetramethylene sulfoxide, butyl sulfoxide, and methylphenyl sulfoxide may be used as sulfoxide derivatives. Tetramethylene sulfone and butyl sulfone may be used as the sulfone derivatives, acetonitrile and preiononitrile may be used as the nitrile compound derivatives, and 1,3-dimethyl-2imidazolididone may be used as the urea derivative. have.

In the present invention, a mixed aqueous solution of two or more polar solvents, alkoxyethanol such as 2-methyl-1,3-hexanediol and dimethyl sulfoxide, di (ethylene glycol) hexyl ether, dimethyl sulfoxide and 2-butoxyethanol And dimethyl sulfoxide, 2-ethyl-1,3-hexanediol and acetonitrile are mixed and used.

The mixed aqueous solution used in the present invention is used in an aqueous solution of 0.01 to 8% by weight. In the present invention, U.S. Patent 5,576,057. The use of much smaller amounts than the polar solvents used in US Pat. No. 5,614,099 has the same or much higher flow rates.

Di (ethyleneglycol) hexyl ether is used as a polar solvent and exhibits excellent physical properties, especially in 0.1-0.3 wt% aqueous solution, when the effect of improving the flow rate is in 0.01-0.3 wt% aqueous solution. 2-ethyl-1,3-hexanediol is also used as a polar solvent and shows excellent physical properties in an aqueous solution of 0.1 to 1.0% by weight. Alkoxy ethanol is used as a polar solvent and shows excellent physical properties in an aqueous solution of 0.05 to 4% by weight. It uses 1-butanol as a polar solvent and shows excellent physical properties in an aqueous solution of 0.01-2% by weight. Tetramethylene sulfone or methylphenyl sulfoxide is used as a polar solvent and shows excellent physical properties in an aqueous solution of 0.01 to 4% by weight. Butyl sulfone is used as a polar solvent and shows excellent physical properties in an aqueous solution of 0.01 to 0.5% by weight. Dimethyl sulfoxide is used as a polar solvent and shows excellent physical properties in an aqueous solution of 0.1 to 7% by weight.

Although not defined by a specific principle in the present invention, the mixed use of the amine salt and the polar solvent shows an effect of significantly improving the flow rate. The amine salt assists in forming the polyamide pores and the polar solvent in the process of forming the membrane at high temperature. It is assumed that there is an effect acting as a catalyst.

The amine reactive compound in the present invention is selected from one or more compounds from the group consisting of polyfunctional acyl halide polyfunctional sulfonyl halide polyfunctional isocyanates. In particular, monomers and aromatic compounds, trimezoyl chloride (TMC), isophthaloyl chloride (IPC), terephthaloyl chloride which are polyfunctional acylides

(TPC) and mixtures thereof.

The organic solvent solution used as the solvent of the amine reactive compound is composed of an organic solution that is poorly mixed with water, and the amine reactive compound is present in the range of 0.005 to 5% by weight in the organic solvent. It is more preferable to exist in the range of 0.01 to 0.5 weight%. The aforementioned organic solvents include hexane, cyclohexane, heptane, alkanes having 8 to 12 carbon atoms, halogen substituted hydrocarbons of freons, and the like. Preferably, a mixed organic solution composed of alkanes having 8 to 12 carbon atoms is used, and such a solution is ISOPAR (EXXON).

According to the present invention, after the aqueous solution is coated on the porous support layer described above by hand coating or continuous process, the excess solution of the support layer is removed by a suitable method such as rolling, spawning or air nipping. After removing the excess solution, the applied support layer material is kept in this state for 5 seconds to 10 minutes after contact with the organic solution described later by dipping or spraying. Preferably 20 second-4 minutes are more preferable. The resulting product is dried. The drying temperature is 50 to 130 ° C., especially for 1 to 10 minutes (more preferably 2 to 7 minutes) at 70 to 100 ° C., followed by 1 to 30 minutes of washing in a basic aqueous solution at room temperature to −95 ° C. .

Although an Example and a comparative example are given to the following and this invention is demonstrated to it further more concretely, the scope of the present invention is not limited by these.

Example 1

A polysulfone support layer formed on a 140 μm thick nonwoven fabric was immersed in an aqueous solution containing 2.0 wt% MPO, 2.3 wt% CSA, and 1.1 wt% TEA, 2.0 wt% BE for 40 seconds. After removing the excess solution of the support layer was immersed in a solution layer dissolved 0.1% by weight of trimezoyl chloride in an isopa (EXXON) solvent for 1 minute to remove the excess solution. The resultant composite membrane was dried at room temperature for 1 minute and washed with water at about 40-60 ° C. in an aqueous solution of Na ₂ CO _{3 at} 0.1 wt% for at least 30 minutes. The reverse osmosis membrane thus obtained was measured at a pressure of 225 PSI in 2,000 ppm NaCl aqueous solution to obtain a 99.0% salt removal rate and a flow rate of 37GFD.

Example 2-36, Comparative Example A-V

The reverse osmosis membranes of Comparative Examples A to W and Examples 2 to 36 were prepared by the method of Example 1 using the polar solvent of Table 1 instead of 2.0 wt% of BE. Table 1 shows the results of measuring the physical properties of various solvents of Comparative Examples A to V and Examples 2 to 36 at various concentrations by the method of Example 1.

Example 37

The reverse osmosis membrane of Example 1 was prepared by using 0.3 wt% EHD instead of 2.0 wt% BE, and 1 wt% TMGU and 1.6 wt% TSA instead of CSA and TEA. The reverse osmosis membrane thus obtained was measured at a pressure of 225 PSI in an aqueous solution of 2,000 ppm NaCl to obtain 96.3% salt bran ratio and a flow rate of 43.4 GFD.

[Examples 38 to 78 and Comparative Examples X to AL]

Using the organic solvent of Table 2 instead of 0.3% by weight of EHD, and the amines of Table 2 instead of 1% by weight of TMGU and 1.6% of TSA by the method of Example 37 in Comparative Examples X-AL and Examples 38-78. Reverse osmosis membrane was prepared. The results of measuring physical properties of various solvents at various concentrations by the method of Example 37 are shown in Table 2 below.

* Abbreviations Used in Table 2

Amine salt DMI: 1,2-dimethylimidazole

                       TMGU: 1,1,3,3-tetramethylguanidine

                       TMBD: N, N, N ', N-tetramethyl-1,3-butanediamine

                       DABCO: 1,4-diazabicyclo [2,2,2] octane

                       BTAC: benzyltrimethylammonium chloride

                       TEA: Triethylamine

                       DMBA: N, N-dimethylbenzylamine

Strong acid TSA: toluenesulfonic acid

                       CAS: Kempsulfonic Acid

                       MSA: methanesulfonic acid

Polar solvent EHD: 2-ethyl-1,3-hexanediol

                       DMSO: Dimethyl Sulfoxide

                       DEGHE: Diethylene Glycol Hexyl Ether

                       BE: Bucocethanol

                       TEGO: Triethylene Glycol Dimethyl Ether

TABLE 1

TABLE 2

As shown in the above examples and comparative examples, the polyamide reverse osmosis composite membrane obtained in accordance with the present invention has high salt rejection and high flow characteristics even under low pressure, and thus may be particularly useful for desalination of brine or seawater. .

Claims (10)

0.3 to 12 wt% of a salt compound in 0.1 to 20 wt% of a multifunctional monomer amine having at least two or more amine functional groups; And 0.01-8% by weight of a polar solvent and a mixed solvent with water; 0.005-5% by weight of an amine-reactive compound selected from the group consisting of an aqueous solution containing a polyfunctional acyl halide, a polyfunctional sulfonyl halide, and a polyfunctional isocyanate Polyamide reverse osmosis composite membrane, characterized in that the organic solution (ii) containing is cross-linked by interfacial polymerization on the porous support layer. delete The polyamide reverse osmosis composite membrane according to claim 1, wherein the salt compound is a complex salt prepared by reacting a strong acid with a tertiary amine. The polyamide reverse osmosis composite membrane according to claim 1, wherein the salt compound is a complex salt prepared by reacting a strong acid with a polyfunctional tertiary amine. delete The polyamide reverse osmosis of claim 3 or 4, wherein the strong acid is any one selected from the group consisting of methanesulfonic acid, toluene sulfonic acid, kempsulfonic acid, ethanesulfonic acid, nitric acid, hydrochloric acid, sulfuric acid, and trifluoroacetic acid. Composite membrane. The method of claim 1, wherein the polar solvent is one or more selected from the group consisting of ethylene glycol derivatives, propylene glycol derivatives, 1,3-propanediol alkyl substituent, sulfone derivatives, nitrile derivatives and urea derivatives The polyamide reverse osmosis composite membrane. Aqueous solution consisting of a mixed solvent in which 0.1 to 20% by weight of a polyfunctional monomer amine having at least two or more amine functional groups on the porous support layer, 0.3 to 12% by weight of a salt compound and 0.01 to 8% by weight of a polar solvent are dissolved in water. After applying After interfacial reaction with an organic solution (ii) containing 0.005 to 5% by weight of an amine-reactive compound selected from the group consisting of polyfunctional acyl halides, polyfunctional sulfonyl halides and polyfunctional isocyanates, a crosslinked reverse osmosis composite membrane was obtained. Polyamide reverse osmosis composite membrane production method comprising the step of drying. After applying an aqueous solution containing 0.3 to 12% by weight of the salt compound and 0.01 to 8% by weight of the polar solvent on the porous support layer, An aqueous solution containing 0.1 to 20% by weight of a polyfunctional monomer amine having at least two or more amine functional groups is applied thereon, The crosslinked reverse osmosis composite membrane was obtained by interfacial reaction with an organic solution (ii) containing 0.005 to 5% by weight of an amine-reactive compound selected from the group consisting of polyfunctional acyl halides, polyfunctional sulfonyl halides, and polyfunctional isocyanates in the aqueous amine solution. after, The polyamide reverse osmosis composite membrane manufacturing method comprising the step of drying. After applying an aqueous solution containing 0.01 to 8% by weight of a polar solvent on the porous support layer, there are 0.1 to 20% by weight of a multifunctional monomer amine having at least two or more amine functional groups and 0.3 to 12% by weight of a salt compound thereon. Apply an aqueous solution, The crosslinked reverse osmosis composite membrane was obtained by interfacial reaction with an organic solution (ii) containing 0.005 to 5% by weight of an amine-reactive compound selected from the group consisting of polyfunctional acyl halides, polyfunctional sulfonyl halides, and polyfunctional isocyanates in the aqueous amine solution. after, Polyamide reverse osmosis composite membrane production method comprising the step of drying.