JP2001079374A - Polyamide reverse osmosis combined membrane and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide reverse osmosis combined membrane having both characteristics of a satisfactory amount to be permeated and a highly desalting rate and to provide its production method. SOLUTION: A polyamide film is formed on a porous support by reacting an aqueous solution containing multi-functional amine, a polar solvent, at least one quaternary ammonium salt and an amine salt compound having at least one amino group with an organic solution containing an amine-reactive compound having reactivity with amino groups and selected from the group consisting of a multi-functional acyl halide, a multi-functional sulfonyl halide and a multi-functional isocyanate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyamide composite film and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION Solutes in solution can be separated from solvents using various selective membranes. Such membranes include microfiltration membranes, ultrafiltration membranes, and reverse osmosis membranes.

[0003] In order to supply a large amount of industrial water or domestic water by desalinating salt water or sea water, a method using a reverse osmosis membrane is useful. The salt water or seawater desalination treatment using the reverse osmosis membrane is performed by filtering salt water or the like with a reverse osmosis membrane to remove salts that do not pass through the membrane, dissociated ions or particles, and pass only purified water. Is to gain,
At this time, the higher the solute concentration in the feed water, the higher the osmotic pressure and the higher the pressure to be applied in the reverse osmosis step.

[0004] When the salt water or seawater is desalinated commercially using the reverse osmosis membrane method, the performance of the reverse osmosis membrane is 97%.
% Of salt removal is required. In addition, the ability to treat a large amount of water even when the applied pressure is relatively low, that is, a high permeation amount is required.

[0005] Except for the special case where the salt removal rate is more important than the permeation amount, the permeation amount is generally 80% for seawater.
For a pressurization of 0 psi, 10 gallons / ft ² day (gfd) is required, and for a pressurization of 220 psi in the case of salt water, 15 gfd or more is required, and in practice, 22 gfd or more is required in the case of salt water.

The reverse osmosis membrane generally has a structure in which a polyamide layer in the form of a thin film is formed on a porous support, and the polyamide layer is produced by interfacial polymerization of a polyfunctional amine and a polyfunctional acyl halide. You.

As a method for producing this reverse osmosis composite membrane, Cado
tte teaches U.S. Pat. No. 4,277,344 (July 1981).
Discloses that an aromatic polyamide film is produced by interfacial polymerization of an aromatic amine having at least two primary amino groups and an aromatic acyl halide having at least three acyl halide groups. . Specifically, after coating the surface of a porous polysulfone support with an aqueous solution of metaphenylenediamine and removing the excess solution of metaphenylenediamine on the surface, "FREO"
A trimesoyl chloride solution using N "TF (trichlorotrifluoroethane) as a solvent is brought into contact with the surface of the support layer to perform interfacial polymerization (the contact time for interfacial polymerization is 10 seconds, but the reaction itself is completed within 1 second). Describes that the resulting polysulfone / polyamide composite was dried in air to obtain a reverse osmosis composite membrane.

[0008] For the purpose of improving the permeation amount and salt removal rate of a polyamide reverse osmosis composite membrane and improving the chemical modification resistance of the membrane, much research has been conducted on a method for producing a composite membrane using various additives. .

As an example, US Pat.
No. 872,984 discloses a method for producing a reverse osmosis composite membrane by interfacial polymerization, which comprises (A) an aqueous solution containing an aromatic polyamine monomer having at least two amino groups and an amine salt on a microporous support. To form a solution layer, and then (B) an amine-reactive compound having about 2.2 or more acyl halide groups per molecule, and a monomer, a polyfunctional acyl halide or a mixture thereof. And (C) drying the product after contacting an organic solution containing the compound with the solution layer to perform interfacial polymerization.

In Tomashke, the amine salt is a monoamine and a monomer, preferably a water-soluble, strong acid and
It discloses that it is a salt with a secondary amine. Examples of the tertiary amine include trialkylamines such as trimethylamine, triethylamine, and tripropylamine.
N-alkylcycloaliphatic amines such as 1-methylpiperidine; N, N-dialkylamines such as N, N-dimethylethylamine and N, N-diethylmethylamine;
Reference is made to N, N-dialkylethanolamines such as N-dimethylethanolamine, bicyclic tertiary amine compounds such as 3-quinuclidinol, or mixtures thereof. Further, as the amine salt, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetraalkylammonium hydroxide such as tetrapropylammonium hydroxide, and benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, water Benzyltrialkylammonium hydroxides such as benzyltripropylammonium oxide or mixtures thereof are mentioned.

Chau et al., US Pat. No. 4,983,291
No. (registered January 8, 1991) discloses a membrane obtained by an interfacial polymerization reaction on a porous support. For more information,
On a porous support, an aprotic polar solvent, and an aqueous amine solution containing a polyhydric compound that is an acid acceptor is applied, and the polyhydric compound is ethylene glycol, propylene glycol, glycerin, glycol, or the like. A large number of compounds are added in the aqueous solution at 0.1 to
It is stated that 50% is contained. Further, after removing the excess solution of the coated support, it is brought into contact with an organic solution of polyacyl halide to carry out interfacial polymerization (at this time, the contact time is lengthened to form a sufficient polymerization product). About processing the produced composite with hydroxypolycarboxylic acid, polyaminoalkylenepolycarboxylic acid, sulfonic acid, amine salt, amino acid, amino acid salt, polymer acid, inorganic acid, etc., and then drying to produce a composite membrane Also states.

Hirose et al., US Pat. No. 5,576,05.
No. 7 (registered November 19, 1996) discloses the manufacture of a reverse osmosis composite membrane in which a polyamide thin film is coated on a porous support. More specifically, a porous support is coated with a solution (A) containing a compound having at least two amino groups, and is then contacted with a solution (B) containing a polyfunctional halogen acid to produce a solution. And the difference between the solubility constants of the solution (A) and the solution (B) is 7
１５15 (cal / cm ³ ) ^1/2 . As a solvent of the solution (A), ethanol, propanol, butanol, 1-pentanol, 2-pentanol, t-
Amyl alcohol, isoamyl alcohol, isobutyl alcohol, isopropyl alcohol, undecanol, 2-ethylbutanol, 2-ethylhexanol,
Octanol, cyclohexanol, tetrahydrofurfuryl alcohol, neopentyl glycol, t-butanol, benzyl alcohol, 4-methyl-2-pentanol, 3-methyl-2-butanol, pentyl alcohol, allyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol Ethylene glycol, tetraethylene glycol, propanediol, butanediol,
Mixtures of water with alcohols such as pentanediol and glycerol, or mixtures of water with nitrogen compounds such as nitromethane, formamide, methylformamide, acetonitrile, dimethylformamide, ethylformamide and the like.

Further, as an example of the mixing ratio (weight ratio) of water and the solvent in the solution (A), in the case of water / ethanol (5
0-90) / (50-10), preferably (60-9)
0) / (40 to 10).

In JP-A-2-187135 (based on US Pat. No. 4,872,984), Hirose et al. Disclose a tetraalkylammonium halide or a salt comprising a trialkylamine and an organic acid in a solution ( It is disclosed that addition to A) improves the absorbency of the amine solution to the support, and accelerates the reaction to facilitate the formation of a film.

Further, Hirose et al., US Pat.
No. 099 (registered March 25, 1997) relates to 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 has a compound having an amino group and a polyamine having an acyl acid functional group. It is disclosed that it is prepared by reaction with a functional halogenated acid compound. Specifically, after a solution containing metaphenylenediamine is brought into contact with a porous polysulfone support to form a solution layer, the solution is brought into contact with a trimesic acid chloride solution to carry out a reaction, and the resulting film is dried in a drier to form a support. A polymer film is formed on the surface, and then the surface of the polyamide layer is
It discloses that it is treated with a quaternary ammonium salt and coated with an organic crosslinked polymer having a positively charged group.

Hirose et al. Also include alcohols, ethers, ketones, and the like as compounds to be added to the solution (A).
Disclosed are esters, halogenated hydrocarbons, and sulfur-containing compounds, preferably compounds having various amino groups and having a solubility constant of 8 to 14 (cal / cm ² ) ^1/2 .

In addition, Chau US Pat. No. 4,950,4.
No. 04 (registered August 21, 1990); Uemura U.S. Pat. No. 4,761,234 (registered August 2, 1988); Fibiger et al., U.S. Pat. No. 4,769,148 (September 1998). (Registration on the 6th) discloses an invention relating to a reverse osmosis membrane.

The membrane according to the above-mentioned invention of Cadotte et al. Has relatively high water permeability, and has a good permeation amount and a good salt removal rate. However, in practical use, a reverse osmosis membrane with higher performance, which has a high removal rate of salt and the like and can process a large amount of seawater even at a low pressure of about 120 psi, for the purpose of reducing operating costs, is urgently needed. There is a need for further research on improving permeation and salt removal, as required. There is also room for improvement in the resistance of the film to chemical decomposition and the like.

[0019]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a polyamide reverse osmosis composite membrane having both excellent characteristics of a high permeation amount and a high salt removal rate, and its production. It is to provide a method.

[0020]

A reverse osmosis membrane according to the present invention which has achieved the above objects has a polyfunctional amine, a polar solvent, at least one quaternary ammonium salt and at least one amino group. An aqueous solution containing an amine salt compound and an organic solution containing an amine-reactive compound having reactivity with an amino group selected from the group consisting of polyfunctional acyl halides, polyfunctional sulfonyl halides, and polyfunctional isocyanates Has a gist where it is obtained by the reaction with

The polyfunctional amine is at least one selected from the group consisting of aromatic primary diamines, alkane primary diamines, alicyclic primary diamines, alicyclic secondary diamines, and aromatic secondary diamines. Is preferable.

The amine-reactive compound is preferably at least one compound selected from the group consisting of isophthaloyl halide, tetraphthaloyl halide and trimesoyl halide.

Further, the polar solvent is selected from the group consisting of alkoxyalkanols, ethylene glycol derivatives, propylene glycol derivatives, alkanols, 1,3-propanediol derivatives, sulfoxide derivatives, sulfone derivatives, nitrile derivatives and urea derivatives. Preferably, the solvent is at least one kind.

The above-mentioned amine salt compound comprises a strong acid and a polyfunctional 3
It is preferably a reaction product with a secondary amine.

The polar solvent may be the above-mentioned ethylene glycol derivative, triethylene glycol dimethyl ether, or the above-mentioned propylene glycol derivative, propylene glycol butyl ether, or propylene glycol propyl ether, or the above-mentioned alkanol, 1-pentanol, or 1-butanol, or the above-mentioned 1,3-propanediol derivative, 2-ethyl-1,3-hexanediol, or the above-mentioned sulfoxide derivative, tetramethylene sulfoxide, or butyl sulfoxide, or methylphenyl sulfoxide, or dimethyl sulfoxide Or the sulfone derivative, butyl sulfone, or tetramethylene sulfone, or the urea derivative, 1,3-
Dimethyl-2-imidazolidinone, or a combination of two or more polar solvents described above, 2-ethyl-1,3-hexanediol and dimethyl sulfoxide, or diethylene glycol hexyl ether and dimethyl sulfoxide, or 2-ethyl-1, It is preferable to use either 3-hexanediol and acetonitrile, or alkoxyethanol and dimethylsulfoxide.

As the polar solvent, alkoxyalkanol: an amount of 0.05 to 4% in the aqueous solution; 1-pentanol: an amount of 0.01 to 2% in the aqueous solution;
-Butanol: an amount of 0.01 to 3% in the aqueous solution,
Dimethyl sulfoxide: 0.01-8% in the aqueous solution, tetramethylene sulfone: 0.0 in the aqueous solution
Amount to be 1-4%, alkoxyalkanol: 0.05 to 4% in the aqueous solution and dimethyl sulfoxide:
It is desirable to use a solvent selected from the group consisting of a mixed solution having an amount of 0.01 to 8% in the aqueous solution.

The method for producing a polyamide reverse osmosis composite membrane includes a step of applying the aqueous solution on a porous support layer, a step of bringing the organic solution into contact with the solution layer, and forming the polyamide layer on the porous support layer by interfacial polymerization. It is preferable to include a step of forming and a step of drying the product. At this time, the aqueous solution is preferably in a pH range of 7 to 13 due to the addition of an acid acceptor.

The method for producing a polyamide reverse osmosis composite membrane includes a first solution layer forming step of applying a first aqueous solution containing the polar solvent and the amine salt compound to a porous support layer; Second containing multifunctional amine
The method preferably includes a second solution layer forming step of applying an aqueous solution, a step of bringing the organic solution into contact with the solution layer, forming a polyamide layer on the porous support layer by interfacial polymerization, and a step of drying the product.

Further, the method for producing a polyamide reverse osmosis composite membrane includes a first solution layer forming step of applying a first aqueous solution containing the polar solvent to a porous support layer; Second containing amine and the amine salt compound
A second solution layer forming step of applying an aqueous solution,
The method preferably includes a step of contacting the organic solution to form a polyamide layer on the porous support layer by interfacial polymerization, and a step of drying the product.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below.

The present invention provides a novel reverse osmosis composite membrane, which comprises (A) a porous support, (B) (a) a polyfunctional amine, and one or more of: An aqueous solution containing a polar solvent and an amine salt compound, and (b)
A polyamide film formed on the support by reaction with an amine-reactive compound selected from the group consisting of a polyfunctional acyl halide, a polyfunctional sulfonyl halide and a polyfunctional isocyanate. As the amine salt compound, a compound having at least one quaternary ammonium salt and at least one amino group is used.

As the porous support layer, a microporous support layer made of a general polymer material is used, and the pore size of the support layer is not particularly limited. It is desirable to be as large as possible. However, 50
If the thickness exceeds 0 nm, the ultra-thin film sinks into the voids, making it difficult to obtain a desired flat film state. Therefore, the pore diameter of the porous support layer is preferably 1 to 500 nm.

The material of the porous support layer is mainly polysulfone, polyether, polyimide, polyamide,
It is desirable to use various halogenated polymers such as polypropylene or polyvinylidene fluoride. In addition, the materials described in the above reference may be used.

The thickness of the porous support layer is not particularly limited, but is preferably 25 to 125 μm, more preferably 40 to 75 μm.

It is preferable to use a polyfunctional amine having two or more amino groups. The amino group is preferably a primary amino group or a secondary amino group, and more preferably a primary amino group. The polyfunctional amine in the present invention is not particularly limited, and one kind or a mixture of two or more kinds is used.

Examples of the above polyfunctional amines include aromatic primary diamines such as metaphenylenediamine, paraphenylenediamine, and alkyl groups such as methyl group or ethyl group, and alkoxyl groups such as methoxy group or ethoxy group. , A hydroxyalkyl group, a hydroxyl group, a metaphenylenediamine derivative having a substituent such as a halogen atom,
And paraphenylenediamine derivatives. In addition, 1,3-propanediamine or 1,3-propanediamine as a basic skeleton, an alkanediamine having an N-alkyl group or an N-aryl group, cyclohexanediamine which is an alicyclic primary diamine, alicyclic 2 There are piperazine or piperazine derivatives which are secondary diamines, N, N'-dimethyl-1,3-phenylenediamine which is an aromatic secondary diamine, N, N-diphenylethylenediamine, benzidine, xylenediamine or xylenediamine derivative. Other commonly used polyamines may be used. In the present invention, an aromatic primary diamine is preferred, and more preferably metaphenylenediamine.

The concentration of the polyfunctional amine is preferably 0.1 to 20%, more preferably 0.5 to 8%, in the aqueous solution. The above aqueous solution is prepared so as to have a pH of 7 to 13. 0.001-5 for pH adjustment
% Of a basic acid acceptor. Examples of the acid acceptor include, in addition to a trialkylamine, an alkali metal hydroxide, carboxylate, carbonate, borate, phosphate and the like. No.

As the above-mentioned amine salt compound, a compound having at least one quaternary ammonium salt and at least one amino group is used. The amino group is preferably a tertiary amino group.

The amine salt compound preferably has three or four alkyl groups, alicyclic alkyl groups, benzyl groups, alkoxyl groups and / or hydroxyalkyl groups on the nitrogen atom. Therefore, the amine salt compound is 4
It is preferably a tertiary ammonium salt or a reaction product of a strong acid and a tertiary amine.

Examples of the quaternary ammonium salts include tetraalkylammonium hydroxide, tetraalkylammonium hydroxide such as tetrapropylammonium hydroxide, benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, and benzylhydroxide. Examples include benzyltrialkylammonium hydroxide such as tripropylammonium, or a mixture thereof.

When the amine salt compound is a reaction product of a strong acid and a tertiary amine, the tertiary amine may be either a monofunctional tertiary amine or a polyfunctional tertiary amine.

Examples of the above strong acids include methanesulfonic acid, toluenesulfonic acid, camphorsulfonic acid, ethanesulfonic acid, benzenesulfonic acid, other aromatic or aliphatic sulfonic acids, trifluoroacetic acid, nitric acid, hydrochloric acid, sulfuric acid and the like. And the like, and preferred are methanesulfonic acid, toluenesulfonic acid, camphorsulfonic acid, ethanesulfonic acid, and benzenesulfonic acid.

The monofunctional tertiary amines include trialkylamines such as trimethylamine, triethylamine and tripropylamine, N-alkyl alicyclic amines such as 1-methylpiperidine, and N, N'-dimethylethylamine. , N, N'-diethylmethylamine, or N,
And N, N'-dialkylethanolamine such as N'-dimethylethanolamine.

Examples of the polyfunctional tertiary amine to be reacted with a strong acid include 1,4-diazabicyclo [2,2,2] octane (1,4-diazabicyclo [2,2,2] octane; DABC).
O), 1,8-diazabicyclo [5,4,0] undec-7-ene (1,8-diazabicyclo [5,4,0] undec-7-ene),
N, N, N ', N'-tetramethyl-1,3-butanediamine (N, N, N', N'-tetramethyl-1,3-butanediamine;
TMBD), N, N, N ', N'-tetramethyl-1,
6-hexanediamine (N, N, N ', N'-tetramethyl-1,6-he
xanediamine), N, N, N ', N', N "-pentamethyldiethylenetriamine (N, N, N ', N', N" -pentamethyl
diethylenetriamine), 1,1,3,3-tetramethylguanidine (1,1,3,3-tetramethylguanidine; TMG
U), N, N, N ', N'-tetramethylethylenediamine (N, N, N', N'-tetramethylethylenediamine; TME
D), 1,2-dimethylimidazole (MDI), 1-alkylimidazole-substituted compounds and other USSN09 / 991,1 as imidazole-substituted products
It is preferable to use a substituted imidazole of the type described in 10 or a mixture thereof. It is desirable to use a non-polymerized monomer for such a polyfunctional tertiary amine.

When an amine salt compound is formed by reacting the polyfunctional tertiary amine with a strong acid, a polyfunctional tertiary tertiary compound having n (n is 2 or more, the same applies hereinafter) tertiary amino groups is used. The molar ratio of amine to strong acid is preferably 1: (1 or more, n or less) (USSN 09 / 067,891, mentioned in the references). More preferably, the ratio is 1: (1 or more and 0.95 n or less), and further preferably 1:
(1 or more and 0.9n or less).

The reason why the permeation amount can be remarkably improved in the present invention is that a quaternary ammonium salt freely functions as a void-forming agent of a polyamide film, while a tertiary amino group is a polyfunctional amine (for example, a meta-functional amine). It is considered that the compound acts as an acceptor for an acid generated by an interfacial polymerization reaction between phenylenediamine) and an amine-reactive compound (for example, trimesic acid chloride). By using the amine salt compound of this type, it has only a quaternary ammonium salt,
The permeation amount is remarkably improved as compared with the case where an amine salt compound having no tertiary amino group is used.

The amine salt compound used in the present invention is preferably 0.3 to 12% in an aqueous solution, and more preferably 0.6 to 8% in an aqueous solution.

As described above, the aqueous solution contains one or more polar solvents in addition to the polyfunctional amine and the amine salt compound. The polar solvent is selected from the group consisting of alkoxyalkanols, ethylene glycol derivatives, propylene glycol derivatives, alkanols, 1,3-propanediol derivatives, sulfoxide derivatives, sulfone derivatives, nitrile derivatives, urea derivatives, and mixtures thereof. It is desirable to use one.

Examples of the alkoxyalkanol include 2-methoxyethanol, 2-ethoxyethanol and 2-propoxyethanol.

Examples of the ethylene glycol derivative include diethylene glycol-t-butyl methyl ether, diethylene glycol hexyl ether, and triethylene glycol dimethyl ether. Examples of the propylene glycol derivative include propylene glycol butyl ether and propylene glycol propyl ether.

The alkanol is 1-pentanol, 1-butanol, and the 1,3-propanediol derivative is 1,3-heptanediol, 2-ethyl-1,3-hexanediol, 1,3- Hexanediol and 1,3-pentanediol are exemplified.

The sulfoxide derivative includes:
Tetramethylene sulfoxide, butyl sulfoxide, methylphenyl sulfoxide, dimethyl sulfoxide, as the sulfone derivative, tetramethylene sulfone,
Acetonitrile and propionnitrile as butyl sulfone and the nitrile derivative, and 1,3-dimethyl-2-imidazolidinone as the urea derivative.

Further, two or more polar solvents include 2-ethyl-1,3-hexanediol and dimethyl sulfoxide; diethylene glycol hexyl ether and dimethyl sulfoxide; 2-ethyl-1,3-hexanediol and acetonitrile; Use of dimethyl sulfoxide and the like can be mentioned.

The polar solvent is used in the aqueous solution in an amount of 0.01 to
Preferably, it is 8%. Although the concentration is lower than the concentration of the polar solvent disclosed in U.S. Pat. No. 5,576,057, the present invention has achieved the same or better results.

When an alkoxyalkanol is used as the polar solvent, the content is preferably 0.05 to 4% in the aqueous solution. When 1-pentanol is used, it is preferably 0.01 to 2% in the aqueous solution, and when 1-butanol is used, it is preferably 0.01 to 3% in the aqueous solution. When diethylene glycol hexyl ether is used, the amount of the diethylene glycol hexyl ether in the aqueous solution is preferably from 0.01 to 0.1.
It is preferably 3%, and more preferably 0.1 to 8%.
%. When 2-ethyl-1,3-hexanediol is used, it is preferably 0.1 to 1% in the aqueous solution. When dimethyl sulfoxide is used, it is preferably 0.01 to 8%, more preferably 0.1 to 7% in the aqueous solution. When tetramethylene sulfone or methylphenylene sulfoxide is used, it is preferably 0.01 to 4% in the aqueous solution. When butyl sulfone is used, it is preferably 0.01 to 0.5% in the aqueous solution.

When a mixed solution of an alkoxyalkanol and dimethyl sulfoxide is used, a mixed solution of 0.05 to 4% of alkoxyalkanol in the aqueous solution and 0.01 to 8% of dimethyl sulfoxide in the aqueous solution is used. Preferably, there is.

The reason why the membrane obtained according to the present invention was able to achieve a high permeation amount is considered to be that the combination of the amine salt compound and the polar solvent provided a remarkable improvement in the permeation amount. . That is, it is considered that the amine salt compound acts as a void forming agent, while the polar solvent plays a role of a catalyst in a void forming process of supplying heat to the thin film.

In the present invention, one or more compounds selected from the group consisting of polyfunctional acyl halides, polyfunctional sulfonyl halides and polyfunctional isocyanates are used as the amine-reactive compound capable of reacting with the amine. Further, the amine-reactive compound is preferably at least one compound selected from the group consisting of isophthaloyl halide, tetraphthaloyl halide and trimesoyl halide.

[0059]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples, and the present invention is not limited thereto. Modifications can be made and implemented, all of which are included in the technical scope of the present invention.

Example 1 A microporous polysulfone support formed on a 140 μm-thick nonwoven fabric was coated with 2.0% metaphenylenediamine (MPD), 2.3% camphorsulfonic acid (CSA), .1%
It was immersed in an aqueous solution containing triethyleneamine (TEA) and 2.0% 2-butoxyethanol (BE) for 40 seconds. After removing the excess organic solution on the coated support, Isopar (EXXON)
Was immersed in a 0.1% trimesic acid chloride solution for 1 minute to perform interfacial polymerization, after which excess organic solution was removed. The obtained composite membrane was heated at 90 ° C. for 3 minutes and then immersed in a 0.2% Na ₂ CO ₃ aqueous solution at room temperature for 30 minutes, and then the performance of the membrane was measured. As a result, the permeation amount was 37 gf
d, The salt removal rate was 99%.

<Examples 2 to 36 and Comparative Examples A to W> The procedures were performed in the same manner as in Example 1 except that the polar solvents shown in Tables 1 and 2 below were used. The results of measuring the physical properties of the obtained film are also shown in Tables 1 and 2.

[0062]

[Table 1]

[0063]

[Table 2]

<Example 37> 0.3% as polar solvent
2-ethyl-1,3-hexanediol (EHD), 4
Using 1% 1,1,3,3-tetramethylguanidine (TMGU) as a quaternary ammonium salt and 1.6% toluenesulfonic acid (TSA) as an acid, a reverse osmosis composite membrane was prepared in the same manner as in Example 1. Manufactured. As a result of measuring the physical properties of the obtained membrane, the permeation amount was 43.4 gfd and the salt removal rate was 96.3.
%Met.

<Examples 38 to 78 and Comparative Example X-AI>
Polar solvents, amines and acids, or 4 shown in Tables 3 and 4 below
Example 37 was carried out in the same manner as in Example 37 except that a quaternary ammonium salt was used. The results of measuring the physical properties of the obtained film are also shown in Tables 3 and 4.

[0066]

[Table 3]

[0067]

[Table 4]

As can be seen from the above results, by selecting a specific polar solvent, the permeation amount and the salt removal rate of the obtained reverse osmosis composite membrane show extremely excellent values.

For example, Comparative Examples D and E; Examples 1, 16, 17 and 2 rather than using 2% ethylene glycol dimethyl ether and ethylene glycol diethyl ether
%, 0.1%, 4% It can be seen that using 2-butoxyethanol (ethylene glycol monobutyl ether) results in a membrane that achieves a higher permeation rate and higher salt rejection.

Further, the film obtained using 0.2% diethylene glycol hexyl ether in Example 25 was compared with the film obtained using a solvent having a structure similar to diethylene glycol hexyl ether in Comparative Examples FI. , Higher permeation rate and salt removal rate.

The remarkably excellent effect on the permeation amount or the permeation amount and the salt removal rate was obtained in Comparative Example J as compared with the case where 2% diethylene glycol diethyl ether was used as the polar solvent. A case where 2% diethylene glycol-t-butyl methyl ether was used. In addition, in Comparative Example O, when using Example 35; tetramethylene sulfone, it was possible to obtain more excellent effects with respect to the permeation amount and the salt removal rate than when using ethyl sulfone.

Further, Comparative Examples E to J and T to
W: Examples 3 to 6; 1%, 0.2%, 0.3%,
It can be seen that excellent effects are obtained when 0.4% EHD is used as the polar solvent.

Further, it has been found that when a specific combination of polar solvents is used together with an amine salt compound, unexpectedly excellent effects can be obtained. For example, BE and DMS
The combination of O or EHD with DMSO significantly increases the permeation compared to using each of these solvents alone with an amine salt compound. Examples include Example 13 (2% DMSO and 2% BE), Example 14 (0.5%
% DMSO and 2% BE) or Example 15 (0.1% DMSO
SO and 0.1% BE) is better than Example 2 (1% DMS
O) or a membrane with a higher transmission rate than in Example 1 (2% BE). However, Example 63 using two polar solvents
However, excellent effects cannot be obtained in all combinations of polar solvents so that the above effects are not observed.

[0074]

The present invention is constituted as described above. By producing a reverse osmosis composite membrane using an aqueous amine solution to which a polar solvent and an amine salt compound are added according to the present invention, desalination of seawater or salt water is achieved. It has become possible to provide a reverse osmosis composite membrane having excellent properties of both salt removal and permeation, which is useful for treatment.

Continuing on the front page (72) Inventor No Won Kim South Korea Busan, Soyong Kuk, 557 Namchun 1-Don, Samik New Beach Apartment. , 505-1308 (72) Inventor Yang Seo Yoon Seoul, Gangnam-ku, Gepo-dong, Hyundai apartment. , 103-605 (72) Inventor Yong Yin Kim Republic of Korea Gyeonggi-do, Yong Yin-Shi, Kihenk-Ip, Nonseorie, San 14-1 F-term (reference) 4D006 GA03 MA03 MA07 MA22 MA31 MA40 MB02 MB06 MC23 MC29 MC45 MC54 MC56X MC58 MC62X MC78X NA41 NA46 NA54 PA01 PB03 PB04 PB05

Claims (11)

[Claims] An aqueous solution containing a polyfunctional amine, a polar solvent, at least one quaternary ammonium salt and an amine salt compound having at least one amino group, a polyfunctional acyl halide and a polyfunctional sulfonyl halide. And a polyamide reverse osmosis composite membrane obtained by reaction with an organic solution containing an amine-reactive compound having reactivity with an amino group selected from the group consisting of polyfunctional isocyanates and polyfunctional isocyanates. 2. The polyfunctional amine is selected from the group consisting of aromatic primary diamine, alkane primary diamine, alicyclic primary diamine, alicyclic secondary diamine, and aromatic secondary diamine. 2. The polyamide reverse osmosis composite membrane according to claim 1, which is at least one kind of compound. 3. The polyamide reverse osmosis according to claim 1, wherein the amine-reactive compound is at least one compound selected from the group consisting of isophthaloyl halide, tetraphthaloyl halide and trimesoyl halide. Composite membrane. 4. The method according to claim 1, wherein the polar solvent is selected from the group consisting of alkoxyalkanols, ethylene glycol derivatives, propylene glycol derivatives, alkanols, 1,3-propanediol derivatives, sulfoxide derivatives, sulfone derivatives, nitrile derivatives and urea derivatives. The polyamide reverse osmosis composite membrane according to any one of claims 1 to 3, which is at least one kind of solvent. 5. The polyamide reverse osmosis composite membrane according to claim 1, wherein the amine salt compound is a reaction product of a strong acid and a polyfunctional tertiary amine. 6. The polar solvent, wherein the ethylene glycol derivative is triethylene glycol dimethyl ether, or the propylene glycol derivative is propylene glycol butyl ether or propylene glycol propyl ether.
Or the alkanol, 1-pentanol or 1-butanol, or the 1,3-propanediol derivative, 2-ethyl-1,3-hexanediol, or the sulfoxide derivative, tetramethylene sulfoxide; Or butylsulfoxide, or methylphenylsulfoxide, or dimethylsulfoxide, or the sulfone derivative, butylsulfone, or tetramethylenesulfone, or the urea derivative, 1,3-dimethyl-2-imidazolidinone, or 2 A combination of two or more polar solvents, 2-ethyl-1,3-hexanediol and dimethyl sulfoxide, or diethylene glycol hexyl ether and dimethyl sulfoxide, or 2-ethyl-
The polyamide reverse osmosis composite membrane according to any one of claims 1 to 5, which is one of 1,3-hexanediol and acetonitrile, or one of alkoxyethanol and dimethyl sulfoxide. 7. As the polar solvent, an alkoxyalkanol: 0.05 to 4% (in weight%, in the aqueous solution,
1-pentanol: an amount of 0.01 to 2% in the aqueous solution, 1-butanol: an amount of 0.01 to 3% in the aqueous solution, dimethyl sulfoxide: 0.1 to 2% of the aqueous solution. In an amount of 0.01 to 8%, tetramethylene sulfone: 0.01 to 4% in the aqueous solution
Alkoxyalkanol: 0.05 to 4% in the aqueous solution
And dimethyl sulfoxide: 0.0
The polyamide reverse osmosis composite membrane according to any one of claims 1 to 6, wherein a solvent selected from the group consisting of a mixed solution having an amount of 1 to 8% is used. 8. A step of applying the aqueous solution on a porous support layer, a step of bringing the organic solution into contact with the solution layer, and a step of forming a polyamide layer on the porous support layer by interfacial polymerization. 2. The method according to claim 1, further comprising a drying step.
A method for producing a polyamide reverse osmosis composite membrane. 9. The aqueous solution is added with an acid acceptor to add p
The method for producing a polyamide reverse osmosis composite membrane according to claim 8, which is in a region of H7 to H13. 10. A first solution layer forming step of applying a first aqueous solution containing the polar solvent and the amine salt compound to a porous support layer, and a second solution containing the polyfunctional amine in the first solution layer. A second solution layer forming step of applying an aqueous solution, a step of contacting the organic solution with the solution layer to form a polyamide layer on the porous support layer by interfacial polymerization, and a step of drying the product. Claim 1
A method for producing a polyamide reverse osmosis composite membrane. 11. A first solution layer forming step of applying a first aqueous solution containing the polar solvent to a porous support layer, wherein a second solution containing the polyfunctional amine and the amine salt compound in the first solution layer. A second solution layer forming step of applying an aqueous solution, a step of contacting the organic solution with the solution layer to form a polyamide layer on the porous support layer by interfacial polymerization, and a step of drying the product. Claim 1
A method for producing a polyamide reverse osmosis composite membrane.