Electrically conductive separation membrane for water treatment, manufacturing method therefor, and water treatment apparatus comprising same

Abstract

Disclosed is an electrically conductive separation membrane for water treatment, comprising: a porous metal support having metal oxide nanowires grown on the surface thereof; and metal catalyst particles formed on the porous metal support and the metal oxide nanowires. Water treatment is performed using an electrocatalyst nanowire separation membrane, according to the present invention, and thus contaminants such as perfluorooctanoic acid, wastewater organic matters and bacteria can be efficiently removed, and the novel electrocatalyst membrane can mitigate membrane contamination, which is caused by the attachment of organic matters or bacteria.

Description

Electrically conductive separation membrane for water treatment, method for manufacturing the same, and water treatment device including the same

[0001] The present invention relates to an electrically conductive separation membrane for water treatment, a method for manufacturing the same, and a water treatment device including the same, and more particularly, to an electrically conductive separation membrane for water treatment formed with metal nanowires capable of performing electrochemical reactivity and filtration and decomposition simultaneously by controlling the pore size of a filter by growing nanowires through alkaline hydrothermal treatment of a porous metal support, and coating an electrocatalyst, a method for manufacturing the same, and a water treatment device including the same.

[0002] Water shortages and pollution caused by population growth, climate change, and industrialization pose serious and urgent threats to sustainable development. This has led to the emergence of water reuse and desalination as alternative solutions, necessitating the development of robust water treatment systems. Membrane processes are considered one of the most promising and feasible alternatives for obtaining clean water from unconventional water sources. However, several critical challenges must be addressed before membrane processes can be adopted. Porous membranes have limitations in removing low-molecular-weight contaminants. High-density membranes can effectively remove dissolved solids, but they are energy-intensive. This leads to reduced water productivity and process stability.

[0003] Conventional porous membrane filters, which act as selective separation barriers, primarily remove contaminants through size exclusion. Recently, the introduction of electrochemically active membranes has expanded the functionality of conventional membranes beyond physical separation. These membranes acquire a positive or negative charge through electrical conductivity, which triggers various surface reactions, including electrostatic interactions between charged substances and the membrane surface, thereby promoting the repulsion and migration of like-charged contaminants across the membrane surface.

[0004] Conventional electrically conductive membranes are fabricated using conductive materials such as carbon nanotubes and carbon graphene, metals such as titanium and nickel, metal oxides such as titanium oxide, and organic polymers such as polyaniline and polypyrrole. In particular, carbon nanotubes and Ti4O7 are among the most widely adopted materials for electrically conductive membranes due to their unique properties, including high electrical conductivity and significant hydroxyl radical production. However, fabricating electrically conductive membranes using carbon nanotubes and Ti4O7 has limitations, such as stability.

[0005] In contrast, TiO2, with its relatively high surface area and photocatalytic activity, is showing potential for use in water treatment applications, including solar disinfection. TiO2 membranes can be manufactured by filtering and hot-pressing a suspension of TiO2 nanoparticles obtained through alkaline hydrothermal treatment. Free-standing TiO2 nanowire membranes can be manufactured by growing high-density TiO2 nanowires on a Ti mesh via hydrothermal treatment. However, their low mechanical strength and brittleness limit their practical application. Furthermore, when integrating these membranes into a housing module, ensuring adequate light irradiation to activate the photocatalyst is also a challenge.

[0006] Therefore, the present inventors have designed and fabricated a novel electrocatalytic membrane structure that possesses stability while solving these problems. Using the resulting electrically conductive membrane, they aim to effectively remove contaminants such as perfluorinated compounds, organic matter, turbidity, and bacteria from general wastewater through electrochemical reactions and filtration. Furthermore, the novel electrocatalytic membrane can mitigate membrane fouling caused by the adhesion of organic matter or bacteria. This reactive nanowire membrane holds promise as a next-generation membrane for water purification and sterilization.

[0007] The present invention has been devised to solve the above problems, and the purpose of the present invention is to provide an electrically conductive separation membrane for water treatment formed with metal nanowires having a high surface area and photocatalytic activity, a method for manufacturing the same, and a water treatment device including the same.

[0008] In addition, the present invention aims to provide a multifunctional electrically conductive separation membrane for water treatment having a filtration function and a function of decomposing and removing pollutants by electrochemical reactivity, a method for manufacturing the same, and a water treatment device including the same.

[0009] In order to solve the above problems, the present invention discloses an electrically conductive separation membrane for water treatment, comprising: a porous metal support having metal oxide nanowires grown on the surface; and metal catalyst particles formed on the porous metal support and the metal oxide nanowires.

[0010] The above porous metal support may include at least one of a fiber and a particulate material.

[0011] The above porous metal support may include one or more metals selected from the group consisting of Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Mo, Sn, and W.

[0012] The above metal catalyst particles may include one or more metals or metal oxides selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, V, Pt, and Ag.

[0013] The above-mentioned electrically conductive separation membrane for water treatment may have a pore size of 0.01 to 1.0 μm.

[0014] The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Equivalent solution resistance is 120 to 250 Ω-cm under Hz frequency conditions. 2 It could be.

[0015] The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Charge transfer resistance is 40 to 120 Ω-cm under Hz frequency conditions. 2 It could be.

[0016] The present invention discloses a method for manufacturing an electrically conductive separation membrane for water treatment, comprising the steps of: preparing a porous metal support; growing metal oxide nanowires on the surface of the porous metal support; and forming metal catalyst particles on the porous metal support and the metal oxide nanowires, in order to solve the above-described problems.

[0017] The step of preparing the porous metal support may include a step of treating the porous metal support with a basic solution; and a step of treating the porous metal support with a carboxylic acid solution and then drying it.

[0018] The step of growing the above metal oxide nanowires may be to hydrothermally treat the porous metal support with an alkaline solution.

[0019] In the above heat treatment, the concentration of the alkaline solution may be 5 to 20 M.

[0020] The above heat treatment can be performed at 70 to 250°C for 4 to 30 hours.

[0021] The above alkaline solution may contain at least one substance selected from the group consisting of sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, ammonia, sodium carbonate, sodium bicarbonate, potassium carbonate, and potassium bicarbonate.

[0022] The step of forming metal catalyst particles on the porous metal support and the metal oxide nanowires may be performed by any one method selected from the group consisting of doctor's knife, spin coating, dip coating, roll coating, screen coating, spray coating, flow coating, screen printing, ink jet, and drop casting.

[0023] The metal catalyst particles are formed by adding at least one metal or metal oxide selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, Pt and Ag to the porous metal support in an amount of 0.5 to 10 mg / cm. 2 It may be loaded.

[0024] The disclosed technology may have the following effects. However, this does not mean that a particular embodiment must include all or only the following effects, and therefore the scope of the disclosed technology should not be construed as being limited thereby.

[0025] According to the present invention, a metal nanowire film capable of reducing the pore size by self-growing metal nanowires on a porous metal support can be provided.

[0026] In addition, according to the present invention, pollutants such as perfluorinated compounds, organic matter in general sewage, turbidity, bacteria, etc. can be effectively removed through electrochemical reaction and filtration of an electrically conductive separation membrane for water treatment, and contamination of the membrane caused by adhesion of organic matter or bacteria can be alleviated.

[0027] FIG. 1 illustrates a method for manufacturing an electrically conductive separator according to one embodiment of the present invention, showing TiO2 nanowire formation (a) and Sb-SnO2 coating process (b).

[0028] FIG. 2 illustrates a reactor design diagram of an electrically conductive membrane according to one embodiment of the present invention (a) and a U-shaped plastic frame module (b) into which an electrically conductive membrane is inserted.

[0029] FIG. 3 is a FESEM photograph showing the surface morphology of a conductive separator membrane at each processing step according to an embodiment of the present invention, showing a Ti mesh filter without chemical treatment (a), a TiO2 nanowire membrane subjected to alkaline hydrothermal treatment (b), a TiO2 nanowire membrane after ion exchange reaction (c), and a TiO2 nanowire membrane after annealing (d).

[0030] FIG. 4 is an EDS profile of a membrane at each processing step of an electrically conductive separator according to one embodiment of the present invention, showing a Ti mesh filter without chemical treatment (a), a TiO2 nanowire membrane subjected to alkaline hydrothermal treatment (b), a TiO2 nanowire membrane after ion exchange reaction (c), and a TiO2 nanowire membrane after annealing (d).

[0031] FIG. 5 is an XRD profile of a membrane at each processing step of an electrically conductive separation membrane according to one embodiment of the present invention, showing a Ti mesh filter without chemical treatment (a), a TiO2 nanowire membrane subjected to alkaline hydrothermal treatment (b), a TiO2 nanowire membrane after ion exchange reaction (c), and a TiO2 nanowire membrane after annealing (d).

[0032] Figure 6 is an XPS profile of an electrically conductive separator according to one embodiment of the present invention, showing a TiO2 nanowire membrane subjected to alkaline hydrothermal treatment (a) and a TiO2 nanowire membrane after an ion exchange reaction (b).

[0033] FIG. 7 illustrates the pore size of a TiO2 nanowire membrane according to alkaline hydrothermal treatment conditions of an electrically conductive membrane according to one embodiment of the present invention, showing the pore size (a) according to changes in NaOH concentration and hydrothermal treatment temperature, and the pore size (b) according to changes in hydrothermal treatment time when the NaOH concentration is 14 M and the hydrothermal treatment temperature is 190°C.

[0034] Figure 8 is a FESEM photograph of an electrically conductive separator according to one embodiment of the present invention.

[0035] Figure 9 shows the electrochemical characteristics of electrically conductive separators loaded with Sb-SnO2 at various Sb contents according to one embodiment of the present invention, 2.5 mg / cm 2 Cyclic voltammogram (a) of Sb-SnO2 based on Sb doping concentration, 2.5 mg / cm 2 The anode surface charge (b) according to the Sb doping concentration based on Sb-SnO2, the voltage-current diagram (c) according to the Sb-SnO2 loading amount based on 20 mol% Sb, and the anode surface charge (d) according to the Sb-SnO2 loading amount based on 20 mol% Sb are shown.

[0036] FIG. 10 shows SEM and EDS mapping images of a TiO2 nanowire film loaded with Sb-SnO2 according to one embodiment of the present invention.

[0037] FIG. 11 shows the results of physicochemical property tests of a TiO2 nanowire film loaded with Sb-SnO2 according to one embodiment of the present invention, including an XRD profile (a), an XPS profile (b), an EIS profile (c), and pore size (d) depending on the presence or absence of Sb-SnO2.

[0038] Figure 12 illustrates the PFOA decomposition performance of an electrically conductive membrane according to one embodiment of the present invention, showing the change in PFOA when 30 mM of NaCl is added (a) and the change in PFOA according to current density, NaCl concentration, and H2O2 concentration (b).

[0039] FIG. 13 illustrates the results of a secondary wastewater treatment performance test according to whether or not electricity is applied to an electrically conductive separation membrane according to one embodiment of the present invention, showing turbidity removal performance (a), chemical oxygen demand (COD) removal performance (b), bacteria removal performance (c), and TMP profile (d).

[0040] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0041] In describing each drawing, similar reference numerals are used to refer to similar components. Terms such as "first," "second," etc. may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another.

[0042] Throughout this specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0043] The terms "about," "substantially," and the like, as used herein, are used to mean at or near the numerical value when manufacturing and material tolerances inherent to the meanings referred to are presented, and are used to prevent unscrupulous infringers from unfairly exploiting disclosures that contain precise or absolute numerical values ​​to aid understanding of the present disclosure. Furthermore, throughout the present disclosure, the terms "step of ~" or "step of ~" do not mean "step for ~."

[0044] Throughout this specification, the term "combination thereof" included in the expressions in the Makushi format means one or more mixtures or combinations selected from the group consisting of the components described in the expressions in the Makushi format, and means including one or more selected from the group consisting of said components.

[0045] Hereinafter, the water treatment separation membrane and its manufacturing method of the present invention will be described in detail with reference to implementation examples, examples, and drawings. However, the present invention is not limited to these implementation examples, examples, and drawings.

[0046]

[0047] The present invention discloses an electrically conductive separation membrane for water treatment, comprising: a porous metal support having metal oxide nanowires grown on the surface; and metal catalyst particles formed on the porous metal support and the metal oxide nanowires.

[0048] The porous metal support may comprise at least one of fibers and particulate matter. The porous metal support used as a material for the electrically conductive separation membrane for water treatment manufactured through the present invention is preferably a metal mesh filter comprising the fibers and particulate matter.

[0049] The porous metal support may include, but is not limited to, one or more metals selected from the group consisting of Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Mo, Sn, and W. The porous metal support of the present invention is preferably a Ti mesh filter.

[0050] It is preferable that the metal oxide nanowires grow on their own from the porous metal support by subjecting the porous metal support to an alkaline hydrothermal treatment. More preferably, it is preferable that the TiO2 nanowires grow on their own from the Ti mesh filter inside and outside the pores of the Ti mesh filter by subjecting the Ti mesh filter to an alkaline hydrothermal treatment.

[0051] The above metal oxide may be an oxide of one or more metals selected from the group consisting of Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Mo, Sn and W constituting the porous metal support, but is not limited thereto.

[0052] The above metal oxide nanowires may be interconnected with a diameter of 50 to 150 nm.

[0053] It is preferable that the above metal catalyst particles be a metal material that provides electrical conductivity as an electrocatalyst.

[0054] The metal catalyst particles may include, but are not limited to, one or more metals or metal oxides selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, V, Pt, and Ag. The metal catalyst particles are preferably tin-antimony compounds, and more preferably Sb-SnO2.

[0055] The pore size of the electrically conductive separation membrane for water treatment may be 0.01 to 1.0 μm. The pore size of the electrically conductive separation membrane for water treatment can be finely adjusted by controlling the concentration of the alkaline solution of the alkaline hydrothermal treatment, the reaction temperature, and the reaction time, and the pore size is specifically preferably 0.01 to 0.4 μm. The average size of most pollutant particles in wastewater effluent is 1 μm, and since the size of the pollutant particles is larger than the pore size of the membrane, the pollutant particles can be easily filtered by the membrane itself. When the pore size of the water treatment separation membrane is less than 0.01 μm, the pore size may be too small, which may cause a problem of blocking the flow of wastewater effluent. On the other hand, when the pore size of the water treatment separation membrane is more than 1 μm, the pores may be larger than the average particle size (1 μm) of the pollutant particles in the wastewater effluent, which may cause a problem of not being able to filter the pollutants.

[0056] The EIS Nyquist plot of the above-mentioned electrically conductive membrane for water treatment was obtained in a 0.1 M KCl solution containing 5 mM K3[Fe(CN)6] / K4[Fe(CN)6] redox species and a potential amplitude of 10 mV at 0.1 to 10 5 It was measured by experiment under Hz frequency conditions.

[0057] The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Equivalent solution resistance is 120 to 250 Ω-cm under Hz frequency conditions. 2 It could be.

[0058] The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Charge transfer resistance is 40 to 120 Ω-cm under Hz frequency conditions. 2 It could be.

[0059] The equivalent solution resistance and charge transfer resistance are significantly lower than those of a TiO2 nanowire film not coated with the metal catalyst particles. The metal catalyst particles impart electrochemical activity to the film, thereby improving the charge transfer rate and reducing the electrical resistance.

[0060] In addition, the present invention discloses a method for manufacturing an electrically conductive separation membrane for water treatment, comprising the steps of: preparing a porous metal support; growing metal oxide nanowires on the surface of the porous metal support; and forming metal catalyst particles on the porous metal support and the metal oxide nanowires.

[0061] The above-mentioned electrically conductive separation membrane for water treatment is characterized in that it is manufactured through alkaline hydrothermal treatment, ion exchange reaction, metal catalyst particle coating, and annealing processes.

[0062] The above ion exchange reaction is performed by ultrasonic acid treatment of Na + Ion H + By replacing ions, trititanic acid hydrogen nanowires are formed through the ion exchange reaction. The shape of the metal oxide nanowires is maintained after the ion exchange reaction, but their diameter may decrease. This may be due to the loss of water from the layered structure of sodium titanate.

[0063] The method for manufacturing the electrically conductive separation membrane for water treatment may further include an annealing step after each of the steps of growing metal oxide nanowires on the surface of the porous metal support and forming metal catalyst particles on the porous metal support and the metal oxide nanowires. The annealing step may be performed at 300 to 700°C for 10 minutes to 4 hours, and more specifically, is preferably performed at a temperature of 550°C. If the heating temperature and time of the annealing step are less than 300°C and 10 minutes, dehydration may not occur properly, which may cause a problem of reduced durability of the electrically conductive separation membrane for water treatment. If the heating temperature and time of the annealing step are more than 700°C and 2 hours, a problem of structural deformation such as excessive crystallization may occur. By performing the annealing step within the above-described temperature and time ranges, the metal oxide nanowires can exhibit a more uniform diameter while maintaining the same structure.

[0064] The step of preparing the porous metal support may include a step of treating the porous metal support with a basic solution; and a step of treating the porous metal support with a carboxylic acid solution and then drying it. More specifically, the basic solution is preferably a sodium hydroxide (NaOH) solution, and the carboxylic acid solution is preferably an oxalic acid solution.

[0065] The step of growing the above metal oxide nanowires may be to hydrothermally treat the porous metal support with an alkaline solution.

[0066] In the above hydrothermal treatment, the concentration of the alkaline solution is preferably 5 to 20 M. Specifically, the alkaline solution is preferably 10 to 14 M, and when the concentration of the alkaline solution is less than 5 M, the alkaline hydrothermal treatment may not be performed properly, which may cause a problem in that the metal oxide nanowire structure is not formed. In addition, when the concentration of the alkaline solution exceeds 20 M, the pore size of the electrically conductive separation membrane for water treatment may be excessively reduced, which may cause a problem in that the filtration function of the membrane is reduced. Therefore, the range of the pore size that can be utilized as the separation membrane may be 0.01 to 0.1 um as described above. In summary, in the separation membrane of the present invention, in order to secure a pore size that exhibits excellent separation efficiency, the concentration of the alkaline solution is preferably 5 to 20 M.

[0067] The above alkaline solution may include, but is not limited to, one or more substances selected from the group consisting of sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, ammonia, sodium carbonate, sodium bicarbonate, potassium carbonate, and potassium bicarbonate. It is preferable that the above alkaline solution specifically include sodium hydroxide (NaOH).

[0068] The above-described thermal treatment may be performed at 70 to 250°C for 4 to 30 hours, but is not limited thereto. The thermal treatment is preferably performed at 160 to 190°C for 6 to 24 hours. If the reaction time and reaction temperature of the thermal treatment are less than 4 hours and 70°C, a problem may arise in which the alkaline thermal treatment is not properly performed and a metal oxide nanowire structure is not formed. If the reaction time and reaction temperature of the thermal treatment exceed 30 hours and 250°C, a problem may arise in which the pore size of the electrically conductive separation membrane for water treatment is excessively reduced, thereby reducing the filtration function of the membrane. Therefore, the reaction time and reaction temperature of the thermal treatment are preferably performed within the above-described ranges.

[0069] More specifically, the step of growing the metal oxide nanowires can stably produce the electrically conductive separation membrane for water treatment when alkaline hydrothermal treatment is performed under reaction conditions of 14 M NaOH, 190°C, and 24 hours.

[0070] The step of forming metal catalyst particles on the porous metal support and the metal oxide nanowires may be performed by any one method selected from the group consisting of, but not limited to, doctor's knife, spin coating, dip coating, roll coating, screen coating, spray coating, flow coating, screen printing, ink jet, and drop casting. When mass production is desired, the step of forming metal catalyst particles on the porous metal support and the metal oxide nanowires is economically performed by a method such as spray coating or dip coating.

[0071] The metal catalyst particles are formed by adding at least one metal or metal oxide selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, V, Pt and Ag to the porous metal support in an amount of 0.5 to 10 mg / cm. 2 It may be loaded. The metal catalyst particles are specifically 1.5 to 4.5 mg / cm 2 It is preferable that the loading amount of the metal catalyst particles is 0.5 mg / cm 2 If the loading amount of the metal catalyst particles is less than 10 mg / cm, the problem of insufficient electrical activity due to the metal catalyst to decompose pollutants in wastewater may occur. In addition, if the loading amount of the metal catalyst particles is less than 10 mg / cm, 2 If it is excessive, the metal catalyst particles may block the pores of the electrically conductive separation membrane for water treatment, which may cause a problem in that the filtration function of the membrane is reduced.

[0072] The above metal catalyst particles are preferably Sb-SnO2, but are not limited thereto. In the Sb-SnO2, the electrocatalytic activity can be maximized by controlling the content of Sb and the loading amount of Sb-SnO2. The Sb can be introduced in an amount of 5 to 20 mol%. The Sb-SnO2 containing 20 mol% of Sb is 2.5 mg / cm. 2 It can exhibit the highest catalytic activity when loaded.

[0073] As the above Sb-SnO2 loading amount increases, the current density increases, but at 2.5 mg / cm 2 In the above range, the current density slightly decreased. This is due to the increase in heterogeneity such as the decrease in crystallinity of Sb-SnO2 and the increase in Sb 5+ Sb in 3+ This may be due to the effect of charge recombination.

[0074] The above-mentioned electrically conductive separation membrane for water treatment can effectively remove pollutants such as perfluorinated compounds, organic matter, turbidity, and bacteria in general sewage through electrochemical reaction and filtration, and can alleviate membrane contamination resulting from adhesion of organic matter or bacteria.

[0075] {Examples and Evaluation}

[0076] <Example>

[0077] The present invention will be described in more detail through the following examples; however, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0078] Example 1

[0079] 1. Pretreatment and alkaline hydrothermal treatment

[0080] FIG. 1 illustrates a method for manufacturing an electrically conductive separator according to one embodiment of the present invention, showing TiO2 nanowire formation (a) and Sb-SnO2 coating process (b).

[0081] First, as illustrated in Fig. 1a, a Ti mesh filter was transformed into a TiO2 nanowire membrane by alkaline hydrothermal treatment. The Ti mesh filter, measuring 58 mm in length, 44 mm in width, and 1.10 mm in thickness, was surface-cleaned. The Ti mesh filter was polished using 320-grit abrasive paper, immersed in acetone, and then ultrasonically treated for 15 min using a JAC ultrasonic cleaner to remove organic residues. The Ti mesh filter was then immersed in a boiling 5% NaOH solution at 95°C for 60 min and rinsed with deionized water. The Ti mesh filter was then treated with a 10% oxalic acid solution at 95°C for 90 min and rinsed again with deionized water. The rinsed Ti mesh filter was air-dried before being used in the production of nanowire membranes.

[0082] After this pretreatment process, the Ti mesh filter was transformed into a TiO2 nanowire membrane through alkaline hydrothermal treatment. Fig. 2a illustrates a schematic diagram of a reactor for an electrically conductive membrane according to an embodiment of the present invention (a) and a U-shaped plastic frame module (b) into which the electrically conductive membrane is inserted. Referring to Fig. 2, it can be confirmed that the alkaline hydrothermal treatment for manufacturing a TiO2 nanowire membrane is performed through the following specific process. First, the pretreated Ti mesh filter was fixed in the Teflon frame (60 × 55 × 10 mm) of Fig. 2b, placed in an autoclave containing a NaOH solution, and then slowly cooled to room temperature (about 25 °C). In order to evaluate the effects of the alkaline hydrothermal treatment reaction conditions, the surface characteristics of the TiO2 nanowire membrane were investigated by varying the NaOH concentration (10-14 M), reaction temperature (160-190 °C), and reaction time (6-24 hours). In Example 1, 14 M NaOH was used for thermal treatment at 190°C for 6 hours.

[0083] 2. Ion exchange reaction

[0084] The generated hydrothermal product was thoroughly rinsed with deionized water and treated with acid (0.5 M HCl) using ultrasonic waves for 30 minutes to remove Na + Ion H + was replaced. After that, the acid-treated product was washed with deionized water and annealed in a muffle furnace at 500°C for 2 hours to obtain a TiO2 nanowire film.

[0085] 3. Electrocatalytic coating

[0086] As shown in Fig. 1b, the Sb-SnO2 coating of the TiO2 nanowire film was performed by repeating the drop casting and annealing procedures. The coating solution was prepared by adding metal chloride salt precursors, specifically, SnCl4-5H2O and SbCl3, to a mixture of isopropyl alcohol and HCl at volume percentages of 96 and 4, respectively. The concentration of Sn(IV) was maintained at 0.2 M, and the molar ratio of Sb(III) was varied within the range of 0.05-0.2 M (Sn(IV)=0.95-0.8 M). 1 mL of the precursor solution was carefully added dropwise to the TiO2 nanowire film using a micropipette, followed by drying at 105 °C for 15 min, annealing at 550 °C for 10 min, and cooling to room temperature. This process resulted in a total metal oxide loading (by mass) of approximately 2.5 mg / cm. 2 Repeat sequentially until reaching .

[0087] In Example 1, 2.5 mg / cm of Sb-SnO2 containing 5 mol% Sb was mixed into the TiO2 nanowire film. 2 The electrocatalyst was coated on the TiO2 nanowire film by loading.

[0088] 4. Annealing

[0089] An electrically conductive TiO2 nanowire film coated with an electrocatalyst was prepared according to one embodiment of the present invention by annealing the film by heating the film at 550°C for an additional 2 hours (hereinafter referred to as “Example 1”).

[0090]

[0091] Example 2

[0092] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 1, except that the alkaline hydrothermal treatment was performed for 12 hours (hereinafter referred to as “Example 2”).

[0093]

[0094] Example 3

[0095] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 1, except that the alkaline hydrothermal treatment was performed for 18 hours (hereinafter referred to as “Example 3”).

[0096]

[0097] Example 4

[0098] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 1, except that the alkaline hydrothermal treatment was performed for 24 hours (hereinafter referred to as “Example 4”).

[0099]

[0100] The process conditions for manufacturing Examples 1 to 4 are summarized in Table 1 below.

[0101]

[0102]

[0103] Example 5

[0104] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 4, except that 10 mol% of Sb was incorporated (hereinafter referred to as “Example 5”).

[0105]

[0106] Example 6

[0107] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 4, except that 15 mol% of Sb was incorporated (hereinafter referred to as “Example 6”).

[0108]

[0109] Example 7

[0110] An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 4, except that 20 mol% of Sb was incorporated (hereinafter referred to as “Example 7”).

[0111]

[0112] The electrocatalyst coating process conditions for manufacturing Examples 4 to 7 are summarized in Table 2 below.

[0113]

[0114]

[0115] Example 8

[0116] Sb-SnO2 at 1.5 mg / cm 2 An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 7, except that loading was performed (hereinafter referred to as “Example 8”).

[0117]

[0118] Example 9

[0119] Sb-SnO2 at 3.5 mg / cm 2 An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 7, except that loading was performed (hereinafter referred to as “Example 9”).

[0120]

[0121] Example 10

[0122] Sb-SnO2 at 4.5 mg / cm 2 An electrically conductive TiO2 nanowire film according to one embodiment of the present invention was manufactured in the same manner as in Example 7, except that loading was performed (hereinafter referred to as “Example 10”).

[0123]

[0124] The electrocatalyst coating process conditions for manufacturing Examples 7 to 10 are summarized in Table 3 below.

[0125]

[0126]

[0127] Comparative Example 1

[0128] This is a Ti mesh filter that has not undergone alkaline hydrothermal treatment, ion exchange reaction, electrocatalytic coating, or annealing (hereinafter referred to as “Comparative Example 1”).

[0129]

[0130] Comparative Example 2

[0131] A TiO2 nanowire film was manufactured in the same manner as in Example 1, except that the electrocatalyst coating and annealing were not performed (hereinafter referred to as “Comparative Example 2”).

[0132]

[0133] The process conditions for manufacturing Comparative Examples 1 and 2 are summarized in Table 4 below.

[0134]

[0135]

[0136] Evaluation

[0137] 1. Evaluation of conversion from Ti mesh filter to TiO2 nanowire membrane

[0138] FIG. 3 is an FESEM photograph showing the surface morphology of an electrically conductive membrane at each processing step according to an embodiment of the present invention. More specifically, FIG. 3a is a photograph of the surface of a Ti mesh filter according to Comparative Example 1, FIG. 3b is a photograph of the surface of a TiO2 nanowire membrane manufactured according to Comparative Example 2, FIG. 3c is a photograph of the surface of a TiO2 nanowire membrane after an ion exchange reaction, and FIG. 3d is a photograph of the surface of a TiO2 nanowire membrane after annealing. In Examples 1 to 10, the surfaces of the TiO2 nanowire membranes manufactured in Step 1 and Step 2, respectively, correspond to FIGS. 3b to 3d.

[0139] In addition, Fig. 4 is an EDS profile of a membrane at each processing step of an electrically conductive separator according to an embodiment of the present invention, and the comparative examples and examples corresponding to 4a to 4d are the same as Fig. 3. Referring to Figs. 3 and 4, the surface morphology and chemical composition of the Ti mesh filter and the TiO2 nanowire membrane produced at various reaction steps can be confirmed.

[0140] First, referring to FIG. 3, FIG. 3a shows the surface of the initial Ti mesh filter without any processing, which is composed of randomly oriented interwoven fibers with a diameter of approximately 100 μm, whereas FIGS. 3b to 3d, after alkaline hydrothermal treatment, show the formation of interconnected nanowire structures with an average diameter of 97.7±21.9 nm.

[0141] Also, referring to Figure 3, in Figure 3c after the ion exchange reaction, Na + Ion H + Despite the replacement with ions, the morphology of the nanowires is preserved. At this time, the thickness, i.e., the diameter of the nanowires, slightly decreases to 77.7±16.6 nm, which can be inferred to be due to the loss of water from the layered structure of sodium titanate. Figure 3(d) shows that the TiO2 nanowire film maintains the same nanowire structure after annealing while exhibiting a more uniform diameter of 51.0±2.0 nm.

[0142] Referring to FIG. 4, it can be confirmed that after the hydrothermal treatment, a Na peak is observed, and the atomic ratio of Na / Ti is 1 / 3.18, forming a NaTi3O6(OH)·2H2O structure.

[0143] Figure 5 is an XRD profile of a membrane at each processing step of an electrically conductive separator according to an embodiment of the present invention. Figure 5a is an XRD profile according to Comparative Example 1, Figure 5b is an XRD profile of a TiO2 nanowire membrane manufactured according to Comparative Example 2, Figure 5c is an XRD profile of a TiO2 nanowire membrane after an ion exchange reaction, and Figure 5d is an XRD profile of a TiO after annealing. 2- XRD profiles of nanowire films. Examples 1 to 10 correspond to the XRD profiles of TiO2 nanowire films manufactured in steps 1 and 2, respectively, as shown in FIGS. 5b to 5d.

[0144] Referring to Fig. 5, compared to Fig. 5a, in Figs. 5b to 5d, the unique diffraction peak of the Ti mesh filter itself disappears after alkaline hydrothermal treatment and a new peak appears. It can be confirmed that this corresponds to hydroxide titanate dihydrate (NaTi3O6(OH)·2H2O) having a monoclinic layered structure similar to sodium metatitanate (Na2Ti3O6) commonly observed in layered titanates. This is generally found in layered titanates. In addition, in Fig. 5c, it can be confirmed that a new diffraction peak corresponding to H2Ti3O7 appears after the ion exchange reaction.

[0145] Figure 6 is an XPS profile of an electrically conductive separator according to one embodiment of the present invention, showing a TiO2 nanowire membrane subjected to alkaline hydrothermal treatment (a) and a TiO2 nanowire membrane after an ion exchange reaction (b).

[0146] In this regard, referring to Fig. 6, after the ion exchange reaction, Na + The ions almost disappear, indicating that complete ion exchange has occurred. Finally, Fig. 5(d) confirms that the final structure of the titania nanowire after annealing is a tetrahedral anatase TiO2 phase.

[0147] Based on the above results, the conversion process from a Ti mesh filter to a TiO2 nanowire film can be explained as follows.

[0148] In the initial stage, Ti reacts with NaOH to form octahedral ions of TiO6, which form zigzag chain polymers, sharing corners and Na + Ions and protons (H + ) which leads to the formation of NaTi3O6(OH)·2H2O crystal nuclei (Reaction Scheme 1-(1)). Simultaneously, ammonia is likely to be formed when nitrogen reacts with hydrogen gas (Reaction Scheme 1-(2)). As the reaction progresses, the crystal nuclei grow with a one-dimensional structure, ultimately producing layered NaTi3O6(OH)·2H2O nanowires. The layered titanate promotes significant mobility of interlayer cations through an ion exchange process, followed by Na + Ion H + Hydrogen trititanate (H2Ti3O7) nanowires are formed by replacing the ions (Reaction Scheme 1-(3)). Finally, the trititanate is dehydrated at 550°C to obtain a TiO2 nanowire membrane filter (Reaction Scheme 1-(4)).

[0149] [Reaction Formula 1]

[0150]

[0151] That is, the transformation of a Ti mesh filter into a TiO2 nanowire membrane is achieved through a series of reactions, such as alkaline hydrothermal treatment, ion exchange reaction, and annealing. The pore size of the TiO2 nanowire membrane filter varies depending on the alkaline hydrothermal treatment conditions.

[0152]

[0153] 2. Evaluation of membrane pore size control by alkaline hydrothermal treatment

[0154] Figure 7 illustrates the pore size of a TiO2 nanowire membrane according to alkaline hydrothermal treatment conditions of an electrically conductive membrane according to an embodiment of the present invention. More specifically, Figure 7a shows the pore size of a TiO2 nanowire membrane according to changes in NaOH concentration and hydrothermal treatment temperature, and Figure 7b shows the pore size of a membrane manufactured according to Examples 1 to 4 according to hydrothermal treatment time.

[0155] Referring to Fig. 7, it can be confirmed that the pore size of the membrane gradually decreases from 10.65±0.94 μm to 0.27±0.10 μm as the NaOH concentration, reaction temperature, and reaction time increase. In addition, referring to Fig. 7b, it can be confirmed that the pore size of the membrane decreases as the hydrothermal treatment reaction time increases in Examples 1 to 4 compared to the Ti mesh filter according to Comparative Example 1. In summary, this means that the TiO2 nanowire membrane promotes the growth of high-density nanowires as the NaOH concentration, reaction temperature, and reaction time increase. Therefore, the electrically conductive separation membrane for water treatment of the present invention forms a submicron nanowire membrane structure most stably and effectively under the reaction conditions of 14 M NaOH, 190°C, and 24 hours.

[0156] FIG. 8 is a FESEM photograph of an electrically conductive membrane according to an embodiment of the present invention. More specifically, FIGS. 8a to 8f show the membrane surface morphology according to changes in NaOH concentration and hydrothermal treatment temperature of a TiO2 nanowire membrane, and FIGS. 8g to 8j show the membrane surface morphology according to hydrothermal treatment time of membranes manufactured according to Examples 1 to 4.

[0157] Referring to Fig. 8, it can be seen that the gap between each nanowire becomes narrow due to the densely interlocked growth of TiO2 nanowires, and a significant morphological transformation occurs from short nanowires to longer nanowires, especially when the NaOH concentration exceeds 12 M. In Fig. 8, as the reaction time increases, longer and thinner TiO2 nanowires are formed, which can create a high-density network and effectively reduce the pore space and pore size.

[0158]

[0159] 3. Evaluation of electrochemical activity of TiO2 nanowire films

[0160] FIG. 9 illustrates the electrochemical characteristics of electrically conductive separators loaded with Sb-SnO2 at various Sb contents according to one embodiment of the present invention. More specifically, FIGS. 9a and 9b are cyclic voltammograms and anode surface charges of Examples 4 to 7, and FIGS. 9c and 9d are cyclic voltammograms and anode surface charges of Examples 7 to 10.

[0161] Referring to Fig. 9a, it can be seen that the higher the Sb loading, the higher the peak current density, indicating improved electron transfer. This is Sn 4+ Go Sb 5+ This is the result of substitution. Previous studies have also reported that introducing Sb ions into the interstitial position of the SnO2 structure improves electrical conductivity.

[0162] Referring to Fig. 9c, the electrocatalyst content is 1.5 mg / cm 2 2.5 mg / cm 2 When the voltage is increased, the peak current density is 7 mA / cm 2 at 19 mA / cm 2 However, it can be seen that the peak current density slightly decreases as the Sb-SnO2 content increases. This decrease is due to increased heterogeneity such as decreased crystallinity of the Sb-SnO2 catalyst and Sb 5+ Sb in3+ This may be due to the effect of charge recombination in the region.

[0163] In the present study, the cyclic voltammogram was integrated to determine the anode surface charge to confirm the electrically active surface area. Referring to Figures 9b and 9d, 20 mol% of Sb and 2.5 mg / cm of Sb-SnO2 2 It can be confirmed that the film manufactured according to Example 7 coated with Sb-SnO2 as a loading amount exhibits the highest electrocatalytic activity.

[0164]

[0165] 4. Evaluation of physicochemical properties of electrically conductive TiO2 nanowire films

[0166] FIG. 10 shows SEM and EDS mapping images of a TiO2 nanowire film loaded with Sb-SnO2 according to one embodiment of the present invention. More specifically, Fig. 10a is an SEM image of a Sb-SnO2 loaded TiO2 nanowire film at a magnification of 500 nm, Fig. 10b is an SEM image of a Sb-SnO2 loaded TiO2 nanowire film at a magnification of 5 μm, Fig. 10c is an EDS mapping image showing the Ti distribution in a Sb-SnO2 loaded TiO2 nanowire film, Fig. 10d is an EDS mapping image showing the O distribution in a Sb-SnO2 loaded TiO2 nanowire film, Fig. 10e is an EDS mapping image showing the Sb distribution in a Sb-SnO2 loaded TiO2 nanowire film, and Fig. 10f is an EDS mapping image showing the Sn distribution in a Sb-SnO2 loaded TiO2 nanowire film.

[0167] Referring to Fig. 10, Ti0 2- It can be confirmed that Sb-SnO2 particles are uniformly distributed in the nanowire film, and that the nanowires maintain the surface morphology on which they were grown. In addition, Fig. 10 shows that O, Sb, and Sn elements are evenly present in the Ti backbone.

[0168] FIG. 11 shows the results of physicochemical property tests of a TiO2 nanowire film loaded with Sb-SnO2 according to one embodiment of the present invention, including an XRD profile (a), an XPS profile (b), an EIS profile (c), and pore size (d) depending on the presence or absence of Sb-SnO2.

[0169] Referring to Fig. 11a, it can be seen that the electrically conductive TiO2 nanowire film of the present invention exhibits characteristic diffraction peaks at 31.69° and 45.53°, which are consistent with the cubic SnO2 reflection (Pa-3 structure). Here, the presence of a catalyst coating layer on the TiO2 nanowires can be confirmed through the appearance of the SnO2 peak together with the anatase TiO2 XRD peak. At this time, the antimony oxide (Sb2O5) phase is not noticeably present, which is likely because Sn is incorporated into the SnO2 lattice, as reported elsewhere.

[0170] Referring to Fig. 11b, two characteristic peaks at 458.5 eV and 464.2 eV (5.7 eV difference) and satellite peaks in the Ti2p spectrum correspond to TiO2, and the Sn3d doublet exhibits a spin-orbit splitting of 8.4 eV (494.9 eV and 484.5 eV), which is indicative of Sn bonded to oxygen in SnO2. 4+ It can be seen that it matches the ion. Sb3d is antimony (Sb) with a peak intensity ratio of 1.45 and a splitting energy of 9.5 eV, as previously reported. 5+ ) represents a doublet.

[0171] In Fig. 11c, the equivalent solution resistance (R1) is determined by first marking the point where Z', which is the X-axis, is first marked. The higher the coordinates are marked at the larger number, the higher the resistance. The charge transfer resistance (R3) is determined by checking the semicircle of the graph. When the semicircle is perfectly drawn virtually, the larger the size of the semicircle, the larger the R3 is. The lower the R3, the higher the ion diffusion, and the smoother the redox reaction occurs. In the study of the present invention, the equivalent circuit and circuit parameters were obtained as a result of fitting the data using the ZSimpWin software.

[0172] Referring to Figure 11c and Table 5, a 0.1 M KCl solution containing 5 mM K3[Fe(CN)6] / K4[Fe(CN)6] redox couple and a potential amplitude of 10 mV at 0.1-10 5 When tested under Hz frequency conditions, the membrane manufactured according to Example 7 had a 141.5 Ω-cm higher modulus than the membrane manufactured according to Comparative Example 2. 2 Equivalent solution resistance (R1) of 53.24 Ω-cm 2 It shows the charge transfer resistance (R3), through which it can be confirmed that the TiO2 nanowire film has electrochemical activity due to the electrocatalytic coating.

[0173] Referring to FIG. 11d, it can be confirmed that the pore size of the membrane manufactured according to Example 7 is 0.27 μm and the porosity is 65%, which is almost unchanged compared to the membrane manufactured according to Comparative Example 2. This indicates the structural integrity of the membrane.

[0174]

[0175]

[0176] 5. Evaluation of the applicability of electrically conductive TiO2 nanowire films

[0177] Figure 12 illustrates the PFOA decomposition performance of an electrically conductive membrane according to one embodiment of the present invention, showing the change in PFOA when 30 mM of NaCl is added (a) and the change in PFOA according to current density, NaCl concentration, and H2O2 concentration (b).

[0178] Referring to FIG. 12a, when no electricity was applied to the electrically conductive TiO2 nanowire film of the present invention, no PFOA decomposition was observed even when up to 2 mM of hydrogen peroxide was added, whereas when 10 mA / cm 2 When a current of 0.025 μm was applied, it was confirmed that a significant portion (approximately 48%) of PFOA was decomposed. This result may be due to electro-generated oxidants, such as reactive oxygen species generated by the electrocatalyst Sb-SnO2 loaded on the nanowire film. In Fig. 12a, the PFOA decomposition efficiency was slightly enhanced by the addition of the oxidant H2O2 (2 mM), which can be inferred to be due to the ability of H2O2 to generate additional -OH radicals through single-electron reduction.

[0179] Referring to Figure 12b, it can be confirmed that as the amount of NaCl (30–50 mM) added increases, the amount of PFOA decomposition also increases. This result can be inferred to be due to reactive chlorine species generated on the catalyst surface in addition to active oxygen.

[0180] FIG. 13 illustrates the results of a secondary wastewater treatment performance test according to whether or not electricity is applied to an electrically conductive separation membrane according to one embodiment of the present invention, showing turbidity removal performance (a), chemical oxygen demand (COD) removal performance (b), bacteria removal performance (c), and TMP profile (d).

[0181] Referring to FIG. 13a, it can be confirmed that the turbidity removal rate of the electrically conductive nanowire membrane of the present invention is high regardless of whether electricity is supplied. This is mainly because most pollutant particles in wastewater have a size of about 1 μm, and the nanowire membrane has a pore size of about 0.27 μm, so the pollutant particles are larger than the pores and are easily filtered.

[0182] Referring to FIG. 13b, when electricity was applied to the electrically conductive TiO2 nanowire film of the present invention, the chemical oxygen demand (COD) was reduced by about 53% within one hour, which is a remarkable effect compared to when there was almost no reduction when electricity was not applied.

[0183] Referring to FIG. 13c, it can be confirmed that the electrically conductive nanowire membrane of the present invention has a bacterial inactivation effect by removing bacterial cells by achieving a bacterial removal rate of 2.5 logs or more.

[0184] Referring to Fig. 13d, the TMP value, which indicates the degree of membrane contamination, is lower when electricity is applied than when no electricity is applied, indicating that the electrical activity due to the electrocatalyst loading helps alleviate membrane contamination. More specifically, it can be inferred that the oxidizing agent generated by applying electricity to the electrically conductive nanowire membrane of the present invention decomposes organic contaminants in the membrane and inhibits bacterial adhesion and growth.

[0185]

[0186] According to the present invention, a metal nanowire film capable of reducing the pore size by self-growing metal nanowires on a porous metal support can be provided.

[0187] In addition, according to the present invention, pollutants such as perfluorinated compounds, organic matter in general sewage, turbidity, bacteria, etc. can be effectively removed through electrochemical reaction and filtration of an electrically conductive separation membrane for water treatment, and contamination of the membrane caused by adhesion of organic matter or bacteria can be alleviated.

[0188] The above description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single component may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0189] The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. A porous metal support having metal oxide nanowires grown on the surface; and An electrically conductive separation membrane for water treatment, comprising metal catalyst particles formed on the porous metal support and metal oxide nanowires.

2. In paragraph 1, An electrically conductive separation membrane for water treatment, wherein the porous metal support comprises at least one of fiber and particulate material.

3. In paragraph 1, An electrically conductive separation membrane for water treatment, wherein the porous metal support comprises at least one metal selected from the group consisting of Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Mo, Sn and W.

4. In paragraph 1, An electrically conductive separation membrane for water treatment, wherein the metal catalyst particles include at least one metal or metal oxide selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, V, Pt and Ag.

5. In paragraph 1, The above-mentioned electrically conductive separation membrane for water treatment is an electrically conductive separation membrane for water treatment having a pore size of 0.01 to 1.0 μm.

6. In paragraph 1, The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Equivalent solution resistance is 120 to 250 Ω-cm at Hz frequency conditions. 2 Electrically conductive membrane for water treatment.

7. In paragraph 1, The above-mentioned electrically conductive separation membrane for water treatment is a 0.1 M electrolyte and 0.1 to 10 5 Charge transfer resistance is 40 to 120 Ω-cm under Hz frequency conditions. 2 Electrically conductive membrane for water treatment.

8. Step of preparing a porous metal support; A step of growing metal oxide nanowires on the surface of the porous metal support; and A method for manufacturing an electrically conductive separation membrane for water treatment, comprising the step of forming metal catalyst particles on the porous metal support and the metal oxide nanowires.

9. In paragraph 8, The step of preparing the above porous metal support is: A step of treating the above porous metal support with a basic solution; and A method for manufacturing an electrically conductive separation membrane for water treatment, comprising the step of treating the porous metal support with a carboxylic acid solution and then drying it.

10. In paragraph 8, A method for manufacturing an electrically conductive separation membrane for water treatment, characterized in that the step of growing the metal oxide nanowires comprises hydrothermal treatment of the porous metal support with an alkaline solution.

11. In paragraph 10, A method for manufacturing an electrically conductive separation membrane for water treatment, wherein the concentration of the alkaline solution in the above water heat treatment is 5 to 20 M.

12. In paragraph 10, A method for manufacturing an electrically conductive separation membrane for water treatment, wherein the above-mentioned thermal treatment is performed at 70 to 250°C for 4 to 30 hours.

13. In paragraph 10, A method for producing an electrically conductive separation membrane for water treatment, wherein the alkaline solution comprises at least one substance selected from the group consisting of sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, ammonia, sodium carbonate, sodium bicarbonate, potassium carbonate, and potassium bicarbonate.

14. In paragraph 8, A method for manufacturing an electrically conductive separation membrane for water treatment, wherein the step of forming metal catalyst particles on the porous metal support and the metal oxide nanowires is performed by any one method selected from the group consisting of a doctor's knife, spin coating, dip coating, roll coating, screen coating, spray coating, flow coating, screen printing, ink jet, and drop casting.

15. In paragraph 8, The metal catalyst particles are formed by adding at least one metal or metal oxide selected from the group consisting of Ir, Ru, Sb, Sn, Pb, Pd, V, Pt and Ag to the porous metal support in an amount of 0.5 to 10 mg / cm. 2 A method for manufacturing a loaded electrically conductive separation membrane for water treatment.

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