JP4539341B2 - Composite reverse osmosis membrane and method for producing the same - Google Patents

Description

  The present invention relates to a method for producing a composite reverse osmosis membrane used for wastewater treatment such as production of drinking water and pure water, advanced treatment of sewage such as human waste and household wastewater, purification of industrial wastewater and recovery of valuable resources. .

  In recent years, a membrane separation method has been actively used in the water treatment field as a low-cost process for saving energy and resources. The composite reverse osmosis membrane mainly used for membrane separation is a microporous ultrathin layer made of crosslinked polyamide obtained by polycondensation reaction between an aqueous solution containing a polyfunctional amine component and an organic solution containing a polyfunctional acid halide. The structure is coated on a support membrane and is widely used as a membrane with high permeability and selective separation.

  However, the surface of these composite reverse osmosis membranes usually has a chargeable or hydrophobic part, and if the product is used for a long period of time or there is a charged or hydrophobic substance with a reverse sign in the treated water, The membrane may become dirty, and the amount of permeated water and the desalination rate may decrease. In particular, when a surface active agent such as a detergent is mixed in the treated raw water, this surface active agent may be adsorbed on the membrane surface of the composite reverse osmosis membrane, thereby reducing the membrane separation performance. For this reason, when the treatment with the above composite reverse osmosis membrane is performed, the amount of permeated water is remarkably lowered with the passage of time, and a stable treatment is difficult.

  As a means for solving the problems such as fouling of the film, a polyfunctional amine component added with a linear aliphatic amine component is known (Patent Document 1).

However, this method has a problem that the permeated water amount after the addition of the surfactant is suppressed and the initial permeated water amount is lowered.
JP 2004-50144 A Japanese Patent No. 3284116

  The object of the present invention is to solve the above-mentioned conventional problems, and even when used for the treatment of water containing a surfactant, it has a high desalination rate and a high permeate flow rate, and a composite reverse osmosis with a low permeate flow rate reduction rate. It is to provide a membrane.

In order to achieve the above object, the present invention has the following configuration.
That is, the present invention provides a composite reverse osmosis membrane crosslinked polyamide separating functional layer comprising a polyfunctional amine and a polyfunctional acid halide is formed on a porous support membrane, multi for forming the crosslinked polyamide separating functional layer functional Amin and to guanidines and the other polyfunctional amines are used, and characterized by the presence in the state in which the guanidine is chemically bonded in the crosslinked polyamide crosslinked polyamide separating functional layer .

Moreover, the guanidine is guanidine, aminoguanidine, Guanazoru, diphenyl guanidine, triphenyl guanidine, and is preferably at least one member selected from the group consisting of guanido acetic anhydride.
It is preferable that a coating made of a crosslinked polymer is formed on the surface of the crosslinked polyamide separation functional layer.

The present invention is a multi-functional by reacting a polyfunctional amine and a polyfunctional acid halide by contacting an organic solution containing an aqueous solution and a polyfunctional acid halide containing Amin, porous support film crosslinked polyamide separating functional layer to form a a method for producing a composite reverse osmosis membrane of the present invention described above, the aqueous solution containing the polyfunctional amine emissions is, containing a guanidine and other multifunctional amines And the ratio of guanidine with respect to another polyfunctional amine is 30-50 mass% , It is a manufacturing method of the composite reverse osmosis membrane characterized by the above-mentioned.

  The present invention can provide a composite reverse osmosis membrane capable of maintaining a sufficient amount of permeated water with little decrease in the amount of permeated water even when used for treatment of water containing a surfactant.

The composite reverse osmosis membrane of the present invention comprises a polyfunctional amine and a polyfunctional acid halide by contacting an aqueous solution containing a guanidine and another polyfunctional amine with an organic solution containing a polyfunctional acid halide. is reacted, Ru is prepared by forming a crosslinked polyamide separating functional layer on a multi-porous support membrane.

  In the present invention, the porous support membrane is a layer that does not substantially have separation performance, and is mainly used to give strength to a crosslinked polyamide separation functional layer having separation performance.

  The structure of the porous support membrane is not particularly limited, but it is a structure having fine pores having a uniform pore diameter from the front surface to the back surface of the membrane, or having fine fine pores on one side and the other side from that side. It is preferable that the surface has an asymmetric structure having pores that gradually increase in diameter, and the size of the micropores is preferably 100 nm or less. In addition, the thickness of the porous support membrane is preferably 1 μm to several mm, more preferably 10 μm or more from the viewpoint of membrane strength, and more preferably several 100 μm or less in terms of ease of handling and module processing.

  The material used for the porous support membrane is not particularly limited, and for example, homopolymers or copolymers such as polysulfone, cellulose acetate, cellulose nitrate, polyvinyl chloride, polyacrylonitrile, polyphenylene sulfide, polyphenylene sulfide sulfone are used alone or in combination. can do. Among these materials, polysulfone is preferably used because of its high chemical, mechanical and thermal stability and easy molding.

And polyfunctional Amin for forming a crosslinked polyamide separating functional layer, using the guanidines and other multifunctional amines. Guanidines are compounds having a guanidine skeleton, which can be chemically bonded by reaction with a polyfunctional acid halide , such as guanidine, aminoguanidine, guanazole, diphenylguanidine, triphenylguanidine, Guanide acetic anhydride or the like is used. Among these, guanidine is particularly preferably used from the viewpoint of the performance of the obtained film.

Also as the other polyfunctional amines, for example, m- phenylenediamine, p- phenylenediamine, o- phenylenediamine, 1,3,5-triaminobenzene, p- xylylenediamine, two such diaminopyridine Aromatic compounds having the above amino groups can also be used. In addition, an aliphatic amine component having two or more amino groups such as ethylenediamine, propylenediamine, dimethylethylenediamine, piperazine, and aminomethylpiperidine can also be used. Among these, m-phenylenediamine, p-phenylenediamine, and 1,3,5-triaminobenzene are preferably used in consideration of the reactivity and the performance of the obtained film.

  Examples of the polyfunctional acid halide include trimesic acid halide, benzophenone tetracarboxylic acid halide, trimellitic acid halide, pyromellitic acid halide, isophthalic acid halide, terephthalic acid halide, naphthalenedicarboxylic acid halide, diphenyldicarboxylic acid halide, pyridinedicarboxylic acid. Aromatic acid halides such as acid halides, benzenedisulfonic acid halides, chlorosulfonylisophthalic acid halides can be used. In addition, aliphatic acid halides such as cyclohexanetricarboxylic acid halide, cyclohexanedicarboxylic acid halide, and oxalyl halide can also be used. Of these, considering the solubility in the membrane-forming solvent and the properties of the resulting composite reverse osmosis membrane, it is preferable to use isophthalic acid chloride, terephthalic acid chloride, trimesic acid chloride, and mixtures thereof.

A polyfunctional amine ting to guanidines and other multifunctional amines for forming definitive the composite reverse osmosis membrane crosslinked polyamide separating functional layer of the present invention is used, and the guanidine is crosslinked polyamide separating functional It exists in a chemically bonded state in the crosslinked polyamide of the layer.

Here the guanidine is present in a state chemically bonded after thoroughly washing the composite reverse osmosis membrane obtained by removing the substrate with water, extracted crosslinked polyamide separating functional layer with methylene chloride, dried, and then When the hydrolyzate obtained by hydrolyzing the composite reverse osmosis membrane after extraction in a 6 mol / liter sodium hydroxide aqueous solution at 120 ° C. for 1 hour was measured by 1H-NMR in heavy water, the amine of guanidines This can be confirmed by observing the peak.

  Furthermore, it is preferable to coat a crosslinked polymer on the surface of the crosslinked polyamide separation functional layer. As a heating method when performing thermal crosslinking, for example, a method of blowing hot air can be used. In this case, the heating temperature is preferably in the range of 30 to 150 ° C, more preferably in the range of 30 to 130 ° C, and still more preferably in the range of 60 to 100 ° C. When the heating temperature is lower than 30 ° C, sufficient heating is not performed and the crosslinking reaction rate tends to decrease. When the heating temperature is higher than 150 ° C, the side reaction tends to proceed. Moreover, when thermal crosslinking is performed at 100 ° C. or higher, thermal shrinkage of the composite reverse osmosis membrane may increase, and the amount of permeated water tends to decrease.

  A crosslinking agent is preferably used for crosslinking the water-soluble polymer. Examples of the crosslinking agent include the aldehydes having at least two functional groups in one molecule, such as the acid or alkali, glyoxal, and glutaraldehyde described above. In particular, the raw material of the crosslinked polymer is preferably polyvinyl alcohol, the crosslinking agent is glutaraldehyde, and the crosslinked polymer preferably contains a reaction product of polyvinyl alcohol and glutaraldehyde.

  The concentration of the crosslinking agent added is preferably in the range of 0.01 to 5% by weight, more preferably in the range of 0.01 to 1% by weight, and 0.01 to 0.5% by weight. More preferably within the range. If the concentration is less than 0.01% by weight, the crosslinking density tends to be low and water insolubility of the crosslinked polymer tends to be insufficient, and if it exceeds 5% by weight, the crosslinking density tends to increase and the amount of water produced tends to be low. Furthermore, the crosslinking reaction rate is increased, gelation is likely to occur, and uniform application tends to be difficult. The reaction time for the crosslinking reaction is preferably 10 seconds to 10 minutes. If it is less than 10 seconds, the reaction may not proceed sufficiently, and if it exceeds 10 minutes, the production efficiency decreases.

  The composite reverse osmosis membrane thus obtained can be used as it is, but it is preferable to remove unreacted residues by washing before use. It is preferable to wash the membrane with water in the range of 30 to 100 ° C. to remove the remaining amino compound and the like. The washing can be performed by immersing the support membrane in water within the above temperature range or spraying water. When the temperature of the water to be used is below 30 ° C., the amino compound remains in the composite reverse osmosis membrane and the amount of permeated water tends to be low. Further, when washing is performed at a temperature exceeding 100 ° C. with an autoclave, steam, or the like, the membrane may cause thermal shrinkage, and the amount of permeated water tends to be low.

  Further, for example, the membrane rejection rate and water permeability may be increased by a method of contacting a chlorine-containing aqueous solution having a pH of 6 to 13 at normal pressure or a method of contacting a nitrous acid-containing aqueous solution at normal pressure. preferable.

  Next, the hydrophilicity of the membrane can be increased by contacting the compound with a water-insoluble crosslinked polymer. As this compound, for example, alcohols can be used. Specifically, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, or isobutyl alcohol can be used as the alcohol. Of the above, methyl alcohol, ethyl alcohol, and isopropyl alcohol are particularly preferable, and isopropyl alcohol is more preferable. The concentration to be used is preferably in the range of 0.1 to 50% by weight, and more preferably in the range of 0.5 to 15% by weight. When the concentration exceeds 50% by weight, the cost increases. When the concentration is less than 0.1% by weight, it is difficult to obtain the effect of improving water permeability.

  Next, a preferred method for producing the composite reverse osmosis membrane of the present invention will be described.

First, a polysulfone solution is cast to a certain thickness on a densely woven polyester cloth or non-woven support, and it is wet-coagulated in water. A porous support membrane having the following fine pores is obtained. On the resulting porous support membrane, a multifunctional amine ting and by coating an aqueous solution containing a guanidine and other multifunctional amines, then the polyfunctional acid halide solution by a coating in-situ An interfacial polycondensation reaction is performed to form a polyamide separation functional layer having substantially separation performance. The amount of guanidine contained in an aqueous solution containing the guanidine and other multifunctional amines, from 30 to 50 mass% of the amount of other multifunctional amines. Below 30 wt%, the permeate flow after the addition of the surfactant is significantly reduced, also because the initial amount of permeated water exceeds 50 mass% significantly reduced.

The concentration of the polyfunctional Amin water solution containing guanidine and other multifunctional amines, preferably in the range of 0.1 to 20 wt%, to be within the scope of 1 to 3 wt% More preferred. When polyfunctional Amin concentration is below 0.1 wt%, the progress of the interfacial polycondensation reaction is slow, the film thickness is increased permeability of the separation function layer exceeds 20 wt% tends to decrease.

  The organic solution in which the polyfunctional acid halide is dissolved is immiscible with water, dissolves the polyfunctional acid halide, and does not destroy the structure of the porous support membrane. Any material that can be formed may be used. For example, hydrocarbon compounds, cyclohexane, 1,1,2-trichloro-1,2,2-trifluoroethane and the like can be mentioned. From the reaction rate and solvent volatility, n-hexane, heptane, octane are preferable. , Nonane, decane, undecane, dodecane, 1,1,2-trichloro-1,2,2 trifluoroethane, and the like.

  The concentration of the polyfunctional acid halide in the solvent is preferably in the range of 0.01 to 0.2% by weight, and more preferably in the range of 0.04 to 0.06% by weight. If it is less than 0.01% by weight, the formation of the separation functional layer as the active layer tends to be insufficient.

  As long as the polyfunctional amine component aqueous solution and polyfunctional acid halide solution do not interfere with the reaction between the polyfunctional amine component and the polyfunctional acid halide, an acylation catalyst, a polar solvent, and an acid supplement are added as necessary. An agent, a surfactant, an antioxidant and the like can also be contained.

  The form of the composite reverse osmosis membrane of the present invention is not particularly limited. For example, it may be a flat membrane, a hollow fiber membrane, or a tubular membrane.

The composite reverse osmosis membrane of the present invention uses a sodium chloride aqueous solution having a pH of 6.5 and a concentration of 2,000 mg / l at 25 ° C., and has a permeated water amount of 0.4 to 0.4 when filtered at an operating pressure of 0.5 MPa for 3 hours. It is preferably 3 m ³ / m ² · day. Such a composite reverse osmosis membrane can be manufactured by the manufacturing method mentioned above, for example. By setting the amount of permeated water in the range of 0.4 to ³ m ³ / m ² · day, generation of fouling can be appropriately suppressed and the treatment can be performed stably. Furthermore, it is preferable that it exists in the range of 0.5-1 m < ³ > / m < ² > * day Here, the permeated water amount fall rate is defined as follows. That is, the permeated water amount after passing through a composite reverse osmosis membrane with a sodium chloride aqueous solution having a pH of 6.5 and a concentration of 2,000 mg / l at an operating pressure of 0.5 MPa and filtering for 3 hours at 25 ° C. (F1), and then a nonionic surfactant (polyoxyethylene (10) octylphenyl ether) was added to the aqueous solution so that the concentration was 100 mg / l. When the amount of permeated water after 1 hour is defined as the amount of permeated water (F2), it is defined by the following mathematical formula (1).

  In the composite reverse osmosis membrane of the present invention, the permeated water decrease rate is preferably 0.4 or less. More preferably, it is 0.2 or less. By using the composite reverse osmosis membrane, even when it comes into contact with the surfactant, the adsorption of the surfactant to the membrane surface is hardly observed, and the permeated water amount is little decreased, and a sufficient permeated water amount can be maintained. Therefore, even if it uses for the advanced treatment of the waste_water | drain containing surfactant, high water quality permeated water can be obtained stably.

  The composite reverse osmosis membrane of the present invention can be housed in a housing for easy handling and can be used as a fluid separation element. This fluid separation element is, for example, a flat membrane of a composite reverse osmosis membrane, a separation liquid channel material such as a tricot, and a supply liquid such as a plastic net around a cylindrical liquid collection pipe having a large number of holes. A structure in which a membrane unit including a channel material is wound and these are housed in a cylindrical housing is preferable. A plurality of fluid separation elements can be connected in series or in parallel to form a separation membrane module. Such a separation membrane module can be suitably used for a wastewater treatment apparatus.

  Hereinafter, a preferable process flow of the wastewater treatment apparatus and the wastewater treatment method among the water treatment apparatus and the water treatment method using the composite reverse osmosis membrane will be described.

  First, sewage, which is raw water, is introduced into a screen, sand settling, a preliminary aeration tank, a first settling tank, etc., and subjected to physical treatment to remove suspended matters and oils and fats. At this time, it is also preferable to perform a coagulation treatment with a coagulant or the like in order to increase the removal efficiency. Next, the raw water is introduced into an activated sludge tank or the like and subjected to biological treatment to decompose organic matter in the raw water. Thereafter, suspended substances are removed in a final sedimentation tank to obtain sewage secondary treated water. Subsequently, the sewage secondary treated water is preferably supplied to a sand filtration device, a microfiltration membrane, an ultrafiltration membrane or the like to further remove suspended substances in water. Here, in order to suitably remove microorganisms, it is more preferable to use a microfiltration membrane, an ultrafiltration membrane, or the like. In order to remove a polymer in raw water and reduce membrane contamination in the subsequent stage, an ultrafiltration membrane is used. More preferred is a membrane. The water subjected to such treatment is supplied to the module using the composite reverse osmosis membrane of the present invention to remove salts and organic substances in the raw water. The permeated water from which salts and organic substances in the raw water have been removed can be reused as service water such as hydrophilic water.

  Sewage, which is the main treatment target, may contain a large amount of surfactant for soap and washing drainage, and if a conventional polyamide composite reverse osmosis membrane is used, the amount of permeated water will decrease at an early stage. Although the treatment was difficult, in the present invention, even when in contact with the surfactant, the adsorption of the surfactant to the membrane surface was hardly observed, and the permeated water amount decreased little and stable high quality permeated water was stabilized. Can be obtained.

  Moreover, it is preferable to perform water permeation treatment with a microfiltration membrane or an ultrafiltration membrane before supplying raw water to the composite reverse osmosis membrane of the present invention. As a result, even when biological treatment is performed in the former stage, microorganisms can be suitably removed, so that the latter composite reverse osmosis membrane module can be protected from suspended substances.

  Measurements in Examples and Comparative Examples were performed as follows.

In the examples and comparative examples, the amount of permeated water was evaluated by filtering for 1 hour under conditions of an operating pressure of 0.5 MPa using a sodium chloride aqueous solution having a temperature of 25 ° C., pH 6.5, and a concentration of 2,000 mg / l. . The amount of permeated water was determined by the amount of water permeating the membrane per unit area (m ² ) per unit time (day).

  Further, the amount of permeated water when filtered through a composite reverse osmosis membrane using an aqueous sodium chloride solution at a temperature of 25 ° C., pH 6.5, and a concentration of 2,000 mg / l at an operating pressure of 0.5 MPa is the amount of pre-permeated water (F1 Subsequently, a nonionic surfactant (polyoxyethylene (10) octylphenyl ether) was added to the aqueous sodium chloride solution so that the concentration was 100 mg / l, and the amount of permeated water after 1 hour had passed through. The water amount (F2) was used, and the permeated water amount reduction rate was calculated by Equation (1). The desalting rate was determined by the following formula (2).

  The salt concentration in the permeate and the salt concentration in the feed solution were determined by measuring the electrical conductivity of each solution. The electric conductivity of each liquid was measured using an electric conductivity / pH meter device after washing the electric conductivity cell with ultrapure water and then thoroughly washing with each liquid.

Example 1
A papermaking nonwoven fabric substrate made of polyester fibers and having a size of 30 cm in length and 20 cm in width is fixed on a glass plate, and a 15% by weight dimethylformamide (DMF) solution of polysulfone is 200 μm thick at 25 ° C. It was cast, immediately immersed in pure water and allowed to stand for 5 minutes, and then treated in hot water at 90 ° C. for 2 minutes to obtain a microporous support membrane (hereinafter referred to as FT-PS support membrane). The thickness of this FT-PS support membrane is 200 to 210 μm, and the pure water permeability coefficient is 0.01 to 0.03 g / cm ² · when measured at a pressure of 0.1 MPa, a liquid temperature of 25 ° C., and an ambient temperature of 25 ° C. sec · atm.

  This FT-PS support membrane was immersed in an aqueous solution containing 1.0% by weight of metaphenylenediamine, 0.3% by weight of guanidine and 2.25% by weight of ε-caprolactam for 2 minutes. Next, the support membrane was slowly pulled up in the vertical direction to remove excess aqueous solution from the surface of the support membrane, and then 40 ml of a decane solution containing 0.06% by weight of trimesic acid chloride was applied so that the surface was completely wetted. . Next, after removing the excess solution by removing the excess solution with the film vertical, in order to evaporate the solvent remaining on the film surface, the temperature of 30 ° C. is set so that the wind speed on the film surface is 8 m / s. Air was blown for 1 minute. This membrane was immersed in an aqueous solution containing 1% by weight of sodium carbonate and 0.3% by weight of sodium lauryl sulfate for 2 minutes. After immersion in running water for 5 minutes or more, after immersion in hot water at 90 ° C. for 2 minutes, in order to improve membrane performance, it is immersed in a solution containing 2000 ppm of sodium nitrite adjusted to a temperature of 40 degrees and pH 3.0 for 1 minute. Rinse with distilled water for 20 seconds.

The results obtained were measured for a composite reverse osmosis membrane, salt rejection 98.1% permeate flow is 0.62m ³ · ^{m -2} · day ^-1, the amount of permeated water reduction rate was 55%.

(Example 2)
Film formation and evaluation were performed in the same manner as in Example 1 except that an aqueous solution containing 0.8% by weight of metaphenylenediamine in Example 1 was used.

As a result of measuring with respect to the obtained reverse osmosis composite membrane, the salt rejection was 97.7%, the permeated water amount was 0.68 m ³ · m ⁻² · day ⁻¹ , and the permeated water amount decreasing rate was 57%.

(Example 3)
In Example 1, an aqueous solution containing 0.5% by weight of guanidine was used and the membrane was immersed in an aqueous solution containing 1% by weight of sodium carbonate and 0.3% by weight of sodium lauryl sulfate for 2 minutes up to the previous stage. A film was formed in the same manner as above.

  Next, 0.02 mol of sulfuric acid as an acid catalyst was added to an aqueous solution containing 0.8% by weight of polyvinyl alcohol (weight average molecular weight 2,000, saponification degree 89%) and 0.32% by weight of glutaraldehyde. The aqueous solution added so as to be 1 liter was applied and held for 1 minute. After maintaining for 30 seconds in a vertical direction to cut off excess liquid, the mixture was crosslinked by heating at 60 ° C. for 1 minute using a hot air dryer. It was immersed in running water for 5 minutes or more and immersed in hot water at 90 ° C. for 2 minutes in order to remove uncrosslinked products and acid catalyst. In order to improve the membrane performance, the film was immersed in a solution containing 2000 ppm of sodium nitrite adjusted to a temperature of 40 ° C. and a pH of 3.0 for 1 minute and rinsed with distilled water for 20 seconds. The composite reverse osmosis membrane was hydrophilized by immersing in a 10% by weight isopropanol aqueous solution for 10 minutes before evaluation.

As a result of measuring with respect to the obtained composite reverse osmosis membrane, the salt rejection rate was 97.6%, the permeated water amount was 0.56 m ³ · m ⁻² · day ⁻¹ , and the permeated water amount decreasing rate was 12%.

(Comparative Example 1)
In Example 1, film formation and evaluation were performed in the same manner as in Example 1 except that an aqueous solution having a guanidine composition ratio of 0% was used.

As a result of measuring with respect to the obtained composite reverse osmosis membrane, the salt rejection rate was 97.5%, the permeated water amount was 0.86 m ³ · m ⁻² · day ⁻¹ , and the permeated water amount decreasing rate was 66%.

(Comparative Example 2)
Film formation and evaluation were performed in the same manner as in Example 3 except that an aqueous solution having a guanidine composition ratio of 0% was used among all the amine components of Example 3.

As a result of measuring with respect to the obtained reverse osmosis composite membrane, the salt rejection rate was 98.6%, the permeated water amount was 0.54 m ³ · m ⁻² · day ⁻¹ , and the permeated water amount reduction rate was 25%.

  The measurement results are also shown in Table 1.

The ratio of guanidines to other polyfunctional amines in the polyfunctional amine aqueous solution was 30% by mass in Example 1, 37.5% by mass in Example 2, and 50% by mass in Example 3.

  From Table 1, the following is clear. That is, Examples 1 to 3 were excellent in the desalting rate and the permeated water decrease rate, and the permeated water amount was at a practical level.

Claims (4)

In the composite reverse osmosis membrane crosslinked polyamide separating functional layer formed on the porous support membrane consisting of polyfunctional Amin and the polyfunctional acid halide, a polyfunctional amine emissions in order to form a crosslinked polyamide separating functional layer A composite reverse osmosis membrane characterized in that guanidines and other polyfunctional amines are used , and the guanidines are present in a chemically bonded state in the crosslinked polyamide of the crosslinked polyamide separation functional layer. . The composite reverse osmosis membrane according to claim 1, wherein the guanidine is one or more selected from the group consisting of guanidine, aminoguanidine, guanazole, diphenylguanidine, triphenylguanidine, and guanide acetic anhydride. The composite reverse osmosis membrane according to claim 1 or 2, wherein a coating composed of a crosslinked polymer is formed on the surface of the crosslinked polyamide separation functional layer. By reacting a polyfunctional amine and a polyfunctional acid halide by contacting an organic solution containing an aqueous solution and a polyfunctional acid halide containing polyfunctional Amin, crosslinked polyamide separating functional on a porous support membrane to form a layer, a method for producing a composite reverse osmosis membrane according to any one of claims 1 to 3, the aqueous solution containing the polyfunctional amine emissions is, a grayed guanidine compound and another polyfunctional amine It contained, and method of producing a composite reverse osmosis membrane fraction of guanidines for other multifunctional amine is characterized in that 30 to 50 wt%.