KR20210039747A - Separator having selective moving function of ion - Google Patents

Abstract

The present invention provides an ion-selective conversion pipe type ion separation membrane, which has ion selectivity to select one of both ions with one separator and can be used even at high water pressure and flow rate by increasing chemical resistance and mechanical strength. The ion-selective conversion pipe type ion separation membrane includes a support tube body having a high dielectric constant and made of porous ceramic; a first electrode disposed inside the wall surface of the support tube and composed of an annular screen electrode woven with carbon filament yarn; upper and lower electrode bands attached to the upper and lower edges of the first electrode and provided in a band shape with carbon filaments; and a second electrode provided in a band shape with a carbon filament at a predetermined interval at a position corresponding to the lower electrode band of the first electrode.

Description

Ion Selective Conversion Piping Type Ion Separation Membrane {SEPARATOR HAVING SELECTIVE MOVING FUNCTION OF ION}

The present invention relates to an ion-selective conversion tubular ion separation membrane, and more specifically, has ion selectivity to select one of both ions with one separation membrane, and increases chemical resistance and mechanical response strength, so that it can be used at high water pressure and flow rate. It relates to an ion selective conversion tubular ion separation membrane.

In general, ion exchange resins, ion exchange membranes, and ion separation membranes have different substrates for handling ions, their uses, and their technical differences.

Ion-exchange resin is a light porous solid electrolyte with its own high charge and is made in the form of very small beads.When the resin is immersed in a solution, it absorbs the solution and increases its volume.The degree of increase depends on the structure of the polymer and the ion concentration of the solution. Resins with appropriate chemical composition and physical properties can be arbitrarily synthesized to exchange special ions, so they occupy most of the synthetic ion exchange materials used in laboratories and industries. It is used to remove salts of calcium, magnesium, iron, and manganese from water, to purify sugar, and to concentrate valuable elements such as gold, silver, and uranium from ores. It is also used to make. Usually, the column is filled with particles to cause an exchange reaction.

It can be said that the objective explanation of the ion exchange resin as described above has almost a common mechanism. However, it is a partial mechanism that the exchanged resin can be regenerated through HCl and NaCH solutions and used repeatedly when cited in literature such as an open encyclopedia. In general, when the ion exchange resin is actually used, it is rare that a rejuvenating agent is added directly to the column for regeneration if the ion exchange function is degraded to some extent. The general regeneration method is to wash the resin beads and then precipitate them in a rejuvenating agent.

However, this regeneration process takes a long time, and the regeneration does not mean that it is permanently used, and the ion exchange resin also has a fixed physical quantity that is chemically stable. Since the amount of charge in the resin itself cannot physically have an exchanger that is more than the fixed physical quantity of ions, and the amount of exchanger is determined after chemically exchanging the fixed physical quantity, the limiting volume is virtually ions. It should be considered that the life of the exchange function is over.

For example, while using an OH-type anion resin to remove salt in water, the physical quantity of OH ions fixed by the resin was exchanged and changed to the physical quantity of adsorbed Cl ions. The changed resin needs to be replaced with OH ions for Cl ions, which is a regenerant such as NaOH, so that ion exchange capacity can be created again. However, in the electrolysis process, the amount of ion exchange of the resin becomes insignificant. Ion exchange membranes ignore this exchange function and place importance only on the selectivity of ions. In other words, if a film is placed between the anode and the cathode in the electrolysis process, only selected ions can pass through one side. Like ion exchange resins, regeneration is not required.

The principle of the ion exchange membrane was first introduced in 1890 by Maigrot and Sabates (Maigrot et al. 1890). They used permanganate paper as a separator to remove inorganic ions from the sugar syrup. In addition, since electrodialysis was first introduced in research papers by Morse and Pierce (Morse et al. 1903) in 1903, the electrochemical theories for ion exchange membranes showed rapid development, and they were established in the 1920s. However, until the 1940s, ion exchange membranes remained at the rudimentary stage with little selectivity for ions, and since then, as interest in the electrodialysis process increased in various industries, ions using polymer materials based on phenol-formaldehyde-condensation polymerization. Exchange membranes began to be developed. The current commercialized multi-cell configuration electrodialysis was also made possible by the advancement of the synthesis technology of polymeric ion exchange membranes, and the ion exchange membrane electrolysis began to be used for the production of chemical substances.

Ion-exchange membranes are often made of an ionomer resin having a natural charge as a monomer or synthesized to form a film-type membrane by compression molding or condensing a crosslinking agent. It is known that hydration safety and mechanical stability are logically based on resin, but this is not the case in the electrolytic process with a large manufacturing capacity. In particular, even if only a part of it is damaged because the resistance to strong acid or strong alkali is weak, it is the same as the loss of the whole due to the dense relationship of the structure.

In addition, different from the above ion exchange resin, a crosslinking agent is used or molded and compressed, so when it enters an aqueous solution, the volume of the resin particles increases as well as an ion exchange resin, but the crosslinking agent does not increase, so surface damage is easy to come, and a problem has been found in continuous use for a long time. . The disadvantage is that it cannot respond to hydraulic pressure or mechanical bonding strength due to such a weak stress resistance. Ion separation membrane technology is proposed in the background that it is required to develop a technology that improves chemical resistance and mechanical response strength while having an ion selective separation function by compensating for these disadvantages.

On the other hand, the ion exchange membrane has an ion-selective function capable of selectively separating cations and anions in aqueous solutions, so electrodialysis for purifying batteries and organic acids, electrodialysis for recovering acids and bases, and acid and metal species from pickling waste. Diffusion dialysis for recovering water and ultrapure water are widely applied to manufacturing processes, but industrially, they are most often used in electrolysis processes. The electrolysis process is also referred to as electrolysis as illustrated in FIG. 1, and after installing the anode 101 and the cathode 102 at a distance in the aqueous solution 105 with an electrolyte, direct current is passed to send two types of It refers to a chemical process obtained by dividing into the above component substances.

At this time, the ions in the aqueous solution move to the isotropic ions, and positive ions gather in the cathode 102 region, which is the negative electrode, and the -electric anions gather in the anode 101 region, the positive electrode. At this time, the cation obtains electrons in the cathode 102 region to become a neutral material, and the anions lose electrons in the anode 101 region and a chemical change to become a neutral substance occurs to process the material to be obtained. In electrolysis, the main edge is the electrode and the charge, but the separation of the reaction region is also very important. This is because, without separation of the reaction region, the oxidized or reduced substances are diluted and the desired high-purity substance cannot be obtained.

2 is an example of attempting to separate the reaction zone as an example of producing NaOH (caustic soda). Fig. 2A is a production method of a diaphragm method, and Fig. 2B is a production method of an ion exchange membrane method. This is a method of using a separator 103 between the anode 101 and the cathode 102 to separate the anode 101 region and the cathode 102 region. When the scale was increased, the diaphragm 103 was also formed as a cement wall. However, although the area occupied by the diaphragm wall is larger than the moving area of ions, the productivity is lowered and the purity of the target material is improved. It was to develop an ion exchange membrane method that allowed only to pass through. Since the ion exchange membrane method passes only selected ions, it is possible to produce a target material with high purity. As in the example of producing NaOH (caustic soda), the ion exchange membrane method employs a cation exchange membrane 104 to allow only NaOH? ions to pass through and combine with OH ions in water to produce NaOH (caustic soda). The resin monomer in the cathode 102 region has a negative charge.

Therefore, negative ions with the same charge are blocked by the repulsive force and only positive ions of opposite charges pass through. When NaOH (caustic soda) with high purity is produced in the cathode 102 area, the cation exchange membrane 104 in contact with the cathode 102 area is easily corroded and must be replaced at any time. Recently, DuPont has put a material resistant to alkali on the market under the (Nafion)-series brand name to prevent corrosion by depositing a material that is resistant to alkali on the part in contact with the cathode 102 region. Therefore, the direction of installation of the (Nafion) series cation exchange membrane 104 is determined. If the (Nafion)-series cation exchange membrane 104 is installed in the opposite direction without ordinary expert knowledge, corrosion progresses faster and the life of the resin is shortened.

In addition, the ion exchange membrane method is important for the production of adiponitrile (NC(CH2)4CN), which is a raw material for nylon 66 intermediates, and for the production of acids and bases. As discussed above, in the conventionally commercialized ion exchange membrane, the support is all resin. Since the resin monomer is condensed or crosslinked, if it is too thick, the conductivity decreases and the ion selection function decreases. Even if other mechanical supports are bonded to a thin film such as a film, there are inevitable oxidation and corrosion problems, as well as limitations in stress and pressure resistance. The present invention has an object of solving this limitation.

Only resins that are synthesized do not fix, exchange, or separate ions. Prior to the development of synthetic resins or compounds capable of ion exchange, substances with ion exchange ability were found in natural soils and ores, which became the basis for research and development of ion exchange resins. It can be seen that if inorganic substances are negatively charged but have positive charges statically, ions can be fixed and exchanged.

In addition, if various materials have a charge capable of fixing ions, they can be fixed to the surface and exchanged by an electrolyte. In the case of a compound other than a single elemental substance, ions may be fixed between the bonding rings. However, the conductivity only decreases as much as the resin monomer synthesized.

(Patent Publication No. 0001) KR No. 10-2017-0092481 (Patent Publication No. 0002) KR No. 10-2017-0136388 (Patent Publication No. 0003) KR No. 10-2019-0081745 (Patent Publication No. 0004) KR No. 10-2017-0112562

1) Dzyaz'ko, YS, Belyakov, VN, Stefanyak, NV, Russ J Appl Chem (2006) 79: 769. (Russian Journal of Applied Chemistry May 2006, Vol. 79, No. 5, pages 769?773) Anion Exchange Characteristics of Composite Ceramic Membrane Containing Zirconium Dioxide 2)RSC Advances (Royal Chemical Association) No. 57, 2015 MC Marti-Calatayud, M. Garcia-Gabaldon, V. Perez-Herranz Ceramic anion exchange membrane based on microporous support impregnated with hydrated zirconium dioxide

The present invention is to provide an ion selective conversion tubular ion separation membrane that has ion selectivity and increases chemical resistance and mechanical response strength so that it can respond to high water pressure and flow rate that was not possible with conventional ion exchange membranes, and that can be mechanically coupled to respond. .

The present invention provides a support tube having a high dielectric constant and a porous ceramic, a first electrode formed of an annular screen electrode disposed inside the wall of the support tube and woven with carbon filament yarn, and upper and lower edges of the first electrode. It consists of a configuration in which upper and lower electrode bands attached to and provided in a strip shape of carbon filaments, and a second electrode provided in a strip shape of carbon filaments at predetermined intervals at positions corresponding to the lower electrode bands of the first electrode are arranged. It features an ion selective conversion tubing type ion separation membrane.

In the construction of the support tube, it is characterized in that it is made of any one ceramic material in which alumina and clay or silica and clay are mixed.

The through hole of the porous ceramic constituting the support tube is characterized in that the 5㎛ to 20㎛ formed.

The number of filaments constituting the first electrode is 200 filaments or less, and the network is 0.1 to 20 μm.

The ion separation membrane is disposed inside the electrolytic module to separate ions while flowing water passes through the electrolytic module, but the electrolytic module has a positive electrode on an inner wall of the tube and a negative electrode at the center of the tube, so that ions between the positive and negative electrodes are provided. It characterized in that the separation membrane is installed.

The voltage of the separation membrane power supply unit applied to the ion separation membrane may be varied to be equal to or lower than the voltage of the electrolytic power supply unit applied to the electrolytic module.

Separation membrane power supply unit applied to the ion separation membrane The output current is characterized in that it can be changed to a lower current than the current of the electrolytic power supply applied to the electrolytic module.

A relay switch for switching the output polarity of the separation membrane power supply unit applied to the ion separation membrane is provided.

The ion selective conversion tubular ion separation membrane according to the present invention provides simplicity in the electrolytic ion separation process by allowing one separation membrane to select one of both ions and convert to another ion, and the stress resistance of the conventional ion exchange membrane is reduced. It has the effect that it can be used even in the environment of large drop-off water treatment or flowing water by solving the disadvantages that it could not be used when there is a hydraulic pressure or a flow rate because it is weak.

1A is an explanatory diagram of a state in which no charge is applied in a conventional electrolysis method
1B is an explanatory diagram showing ion separation in a state in which electric charges are applied in a conventional electrolysis method
Figure 2a is an explanatory diagram showing a membrane-type ion separation in the conventional electrolysis method.
Figure 2b is an explanatory diagram showing ion separation during an ion exchange membrane in a conventional electrolysis method.
3 is an exemplary cross-sectional view showing an exemplary configuration of an ion separation membrane according to the present invention.
4 is a perspective view showing first and second electrodes constituting the ion separation membrane according to the present invention.
5 is an enlarged cross-sectional view of a portion of the first connector in the ion separation membrane according to the present invention.
6 is an enlarged cross-sectional view showing a lower electrode band of a first electrode and a portion of a second electrode in the ion separation membrane according to the present invention.
7 is an exemplary cross-sectional view illustrating a form in which an ion separation membrane according to the present invention is disposed in an electrolytic module.
8 is an exemplary view showing a use state showing that the ion separation membrane according to the present invention is disposed in an electrolytic module to separate ions.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

The ion selective conversion tubular ion separation membrane 100 of the present invention includes a support tube 110 provided with a porous ceramic having a high dielectric constant, and a carbon filament yarn disposed inside the wall surface of the support tube 110. The first electrode 120 is composed of an annular screen electrode woven into, and the upper and lower electrode bands 121 and 122 are bonded to the upper and lower edges of the first electrode 120 and provided in a band shape with carbon filaments. ), and a second electrode 130 provided in a strip shape of carbon filaments at a position corresponding to the lower electrode band 122 of the first electrode 120 at predetermined intervals.

The support tube 110, which is a component of the ion separation membrane 100, has a high dielectric constant and forms a number of through holes through which the aqueous solution can pass, and is provided with a porous ceramic having mechanical strength and chemical resistance, so that it can cope with both the anode region and the cathode region. Make sure you have the conditions that you can.

When the support tube body 110 is configured, it is made of a ceramic material that is a mixture of alumina and clay, or silica and clay, and is a kneaded product formed by kneading such a ceramic material, while having a support tube body 110 having a certain thickness and a support tube body ( 110), the first and second electrodes 120, 130, etc., which are disposed inside the wall surface, are molded in the process of sintering the first and second electrodes 120, 130, etc., and the ceramic is a mixture of the alumina and clay or silica and clay. This is because, by using a material, even if a material with different properties is put inside the molding structure and then sintered during molding, there is no gap with the abnormal material, and the dielectric constant is high, so that polarization can be achieved.

In addition, it is preferable that the pores of the porous ceramic constituting the support tube 110 are formed in a range of 5 μm to 20 μm, which hinders passage of ions when the pores are 5 μm or less, and impurities, etc., are easily formed when the pores are more than 20 μm. There is a disadvantage that the ion separation efficiency is lowered due to the introduction.

Since the carbon filament yarn constituting the first electrode 120 has conductivity and has a higher melting point than tungsten having a higher melting point among metals, the first electrode 120 is composed of an annular screen electrode woven with carbon filament yarns. Even during high-temperature firing of the support pipe 110 or after firing, the shape disposed inside the wall of the support pipe 110 is maintained as it is, and the dielectric constant is not lowered by maintaining a fixed state without being deformed. It provides the movement of free electrons, but the mobility of intrinsic electrons is very low, making it suitable for use in the ion separation function of the present invention.

It is preferable that the number of filaments constituting the first electrode 120 is 200 filaments or less, and the mesh is between 0.1 and 20 μm. This is, when the net is 0.1 μm or less, the passage of ions is prevented, and when the network is more than 20 μm This leads to a result of lowering the selectivity of ions by interfering with the direction of charge movement.

The upper and lower electrode bands 121 and 122 are attached to the upper and lower edges of the first electrode 120 and provided in a band-like form of carbon filaments, so that they do not participate in the passage of ions and have no permeability, and the first electrode 120 ) In a width for evenly distributing electric charges.

A first connector 123 is drawn out to the upper electrode band 121 so that electric charges can be applied from the separation membrane power supply unit 140 configured externally, and the lower electrode band 122 of the first electrode 120 The second electrode 130 is provided in a strip shape with carbon filaments at regular intervals at the lower portion, and the second electrode 130 from which the second connector 131 is drawn is disposed correspondingly.

The distance L between the lower electrode band 122 of the first electrode 120 and the second electrode 130 is 1.5 mm or more to prevent discharge, but the lower electrode of the first electrode 120 It is preferable that the distance (L) between the band 122 and the second electrode 130 is 50% or less compared to the thickness (T) of the support tube 110, which is the lower electrode band of the first electrode 120 If the distance (L) between the (122) and the second electrode (130) is more than 50% of the thickness (T) of the support tube (110), unselected ions may pass as much as the increased cross-sectional area, or the selected ions pass through. The cross-sectional area is reduced, and the direction of the applied current flows from the first electrode 120 to the second electrode 130 in a vertical isotropic shape, and is horizontal toward the flowing water in contact with the support tube body 110 having a high concentration of electrolyte. This is because of the anisotropy of and the blocking function of selective ions and non-selective ions is reduced.

The ion separation membrane 100 configured as described above is disposed inside the electrolysis module 200 so that ion separation is performed in the process of passing the flowing water through the electrolysis module 200.

In the electrolytic module 200, a positive electrode 220 is provided on an inner wall of the electrolytic tube body 210 and a negative electrode 230 is provided in the center of the electrolytic tube body 210, so that ions between the positive electrode 220 and the negative electrode 230 are provided. The separation membrane 100 is installed, and the ions separated by the ion separation membrane 100 are obtained through a separation pipe 240 provided in the flowing water discharge direction.

In addition, the voltage of the separation membrane power supply unit 140 applied to the ion separation membrane 100 is composed of a variable voltage lower than the voltage of the electrolytic power supply unit 250 applied to the electrolysis module 200 and a DC power supply capable of applying a fine variable current. In addition, the separation membrane power supply unit 140 applied to the ion separation membrane 100 includes a relay switch 142 for switching the output polarity. Although the voltage of the separator power supply 140 is lower than the voltage of the electrolytic power supply 250, it is eventually assimilated with the voltage of the electrolytic power supply 250, but the output current of the separator power supply 140 is less than the current of the electrolytic power supply 250. It is low and less than the ionization energy of the electrolyte, so that the selective passage of ions can be efficiently achieved if it is not involved in electrolysis.

Ionization energy refers to the amount of energy required to remove an electron from an isolated atom or molecule. It indicates the degree to which an element can form ions or provide electrons necessary for a chemical reaction. It can also be described as an ionization potential. have. If the potential applied from the separation membrane power supply unit 140 is higher than the ionization potential of the material to be selected, the desired reactant is not formed in the anode area or the cathode area to which the potential for electrolysis is applied, but the reactant in the ion separation membrane 100 area. This is fixed so that the passage and separation of the selected ions are not possible.

In addition, if the current of the separator power supply unit 140 is not varied, the characteristics of chemical bonds in the compound vary depending on the element, so that the ionization energy is different, resulting in an unproductive result of having to provide a power source for each type of target material. In addition, if the relay switch 142 for switching the output polarity of the separation membrane power supply unit 140 is not provided, an anion separation membrane and a cation separation membrane must be separately provided as needed, like a conventional ion exchange membrane.

For example, in order to select sodium ions in the electrolysis process of the electrolysis module 200, the electrolysis potential should be higher than 6910.3 kJ/mol, which is the tertiary ionization energy of sodium. Assuming that the primary ionization energy of 495.8 kJ/mol (3.094 eV) is applied with a potential of 120 Wh, which is 7 to 8 Wh lower than that of 3.094 eV, it is assumed that selection of chlorine ions is required in the same electrolysis module (200) this time. Since the tertiary ionization energy of ions is lower than that of sodium tertiary ionization energy, the primary ionization energy of chlorine is 1251.2 kJ/mol while the electrolytic potential remains as it is. In terms of conversion, energy of about 7.9 eV is required and a potential of about 347.55 Wh is required. Therefore, even if the electrolytic potential is left as it is, a power source for applying a positive charge must be separately provided to the support tube 110 of the ion separation membrane 100 with a potential of about 347.55 Wh to pass and separate the desired chlorine ions.

However, as in the present invention, it is composed of a DC power supply capable of applying a variable voltage lower than the electrolytic voltage and a fine variable current so that the voltage of the separator power supply unit 140 provided externally corresponds to the voltage of the electrolytic power supply unit 250, If there is a relay switch 142 for switching the polarity of the separator power supply 140, it is not necessary to separately provide a separate power supply according to the need to change the polarity of the electric charge and separate power according to conditions. Even if the current level of the appropriate power source is adjusted by varying only about 0 to 1 amp, it is possible to satisfy the object of the present invention, the ion separation, and the ion separation membrane 100 has durability that cannot be compared with the conventional ion exchange membrane.

In the above, the present invention has been described with reference to the above embodiments, but it is of course possible to implement various modifications within the scope of the technical idea of the present invention.

100: ion separation membrane 110: support tube
120: first electrode 121, 122: upper and lower electrode bands
123: first connector 130: second electrode
131: second connector 140: separator power supply
142: relay switch 200: electrolytic module
210: electrolytic tube 220: positive electrode
230: negative electrode 240: separation pipe
250: electrolytic power supply

Claims (8)

A support tube 110 provided with a porous ceramic having a high dielectric constant,
A first electrode 120 formed of an annular screen electrode disposed inside the wall surface of the support tube 110 and woven with carbon filament yarn,
Upper and lower electrode bands 121 and 122 attached to the upper and lower rims of the first electrode 120 and provided in a strip shape of carbon filaments,
Ion selective conversion piping type, characterized in that the second electrode 130 provided in a strip shape of carbon filaments is disposed at a position corresponding to the lower electrode band 122 of the first electrode 120 at a predetermined interval Ion separation membrane.
The method of claim 1,
When the support tube 110 is configured, an ion-selective conversion tubing type ion separation membrane is made of any one ceramic material in which alumina and clay or silica and clay are mixed.
The method of claim 1,
Ion selective conversion tubular ion separation membrane, characterized in that the pores of the porous ceramic constituting the support tube 110 are formed in a range of 5 μm to 20 μm.
The method of claim 1,
Ion selective conversion tubular ion separation membrane, characterized in that the number of filaments constituting the first electrode 120 is 200 filaments or less, and the net is between 0.1 and 20 μm.
The ion separation membrane 100 is disposed inside the electrolytic module 200 to separate ions while flowing water passes through the electrolytic module 200, but the electrolytic module 200 is provided with a positive electrode 220 on the inner wall of the electrolytic tube body 210. ) Is provided and a negative electrode 230 is provided in the center of the electrolytic tube body 210, and an ion separation membrane 100 is installed between the positive electrode 220 and the negative electrode 230. .
The method of claim 5,
Ion selection, characterized in that the voltage of the separator power supply unit 140 applied to the ion separation membrane 100 is a power that can be changed to be equal to or lower than the voltage of the electrolytic power supply unit 250 applied to the electrolysis module 200 Conversion piping type ceramic ion separation membrane.
The method of claim 5,
Of the separation membrane power supply unit 140 applied to the ion separation membrane 100 Ion selective conversion tubular ceramic ion separation membrane, characterized in that the output current can be varied at a lower current than the current of the electrolytic power supply unit 250 applied to the electrolytic module 200.
The method of claim 5,
Ion selective conversion pipe type ceramic ion separation membrane, characterized in that a relay switch (142) for switching the output polarity of the separation membrane power supply unit 140 applied to the ion separation membrane (100) is provided.

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