JP5116710B2 - Electric deionized water production apparatus and deionized water production method - Google Patents

Description

  The present invention relates to a technique for an electric deionized water production apparatus and a deionized water production method used in various industries such as semiconductors, liquid crystals, pharmaceuticals, and food industries, consumer use, and research facilities.

  As a method for producing deionized water, a method of performing deionization by passing water to be treated through an ion exchange resin has been known. However, in this method, when the ion exchange resin is saturated with ions, regeneration is usually performed with a drug. Such regeneration treatment is disadvantageous in processing operation, and in order to eliminate such a point, a deionized water production method by an electric deionization method that does not require regeneration by a chemical agent has been established and has been put into practical use. .

  In an electric deionized water production apparatus (EDI) that performs such desalting treatment, an ion exchanger is partitioned between an anode and a shade by a cation exchange membrane on one side and an anion exchange membrane on the other side. And a concentrating chamber on both sides of the desalting chamber via a cation exchange membrane and an anion exchange membrane. Usually, a plurality of sets of desalting chambers and concentrating chambers are arranged. When deionized water is produced by an electric deionized water production apparatus, water to be treated is placed in a demineralization chamber filled with an ion exchanger in a state where a direct current is passed between the anode and the cathode. By passing the concentrated water, ions in the water to be treated are moved into the concentrated water to obtain deionized water.

  Here, when the hardness of the water to be treated flowing into the desalination chamber is high, for example, when tap water or water obtained by subjecting tap water to RO membrane treatment is used as the water to be treated, a hardness scale is formed on the anion exchange membrane surface of the concentration chamber. Likely to happen. In other words, if the water to be treated contains a carbonate component and a hardness component, calcium ions and magnesium ions that have moved to the concentration chamber of the electric deionized water production apparatus are combined with carbonate ions etc. on the anion exchange membrane surface of the concentration chamber. However, it is easy to produce hardness scales such as calcium carbonate and magnesium carbonate.

  Patent Document 1 proposes an electric deionized water production apparatus in which an anion exchanger having a specific structure is disposed on the anion exchange membrane side of a concentration chamber. According to the apparatus of Patent Document 1, diffusion dilution of OH ions into a concentrated liquid is promoted from the surface of the porous anion exchanger, and the OH ion concentration on the surface of the porous anion exchanger can be quickly reduced. On the other hand, hardness component ions are less likely to enter the interior of the porous anion exchanger, and the opportunity for OH ions and hardness component ions to contact and react with each other is reduced, so that precipitation and accumulation of hardness components are suppressed.

However, when carbonic acid in the water to be treated (generic name for free carbonate, bicarbonate ion, carbonate ion) moves from the desalting chamber to the concentration chamber via the anion exchange membrane on the anode side (details will be described later), The anion exchanger is in the HCO ₃ form. Then, a current flows through the anion exchanger of HCO ₃ form, HCO ₃ ^- (and CO 3 ^_2-) but are attracted to the cation exchange membrane near by the electric field, can not be transmitted through the cation exchange membrane, a cation exchange It is concentrated near the membrane. Further, since hydrogen ions permeate the cation exchange membrane, the pH in the vicinity of the cation exchange membrane is lowered. Then, water and carbon dioxide (CO ₂ ) are generated, and a high-concentration carbon dioxide-containing aqueous solution layer is formed in the vicinity of the cation exchange membrane. Then, the carbon dioxide gas permeates through the cation exchange membrane 10 by diffusion and moves (back diffuses) to the desalting chamber. That is, carbon dioxide once removed from the water to be treated is dissolved again as carbon dioxide gas in the water to be treated, so-called reverse diffusion of carbonic acid occurs, and the treated water discharged from the desalting chamber is contaminated with carbonic acid components. .

In Patent Document 2, by providing a water permeable body having no strongly basic anion group between an anion exchange resin and a cation exchange membrane filled in a concentrating chamber, A deionized water production system has been proposed. According to the apparatus of Patent Document 2, it is possible to prevent the reverse diffusion of carbonic acid by preventing HCO ₃ ^{− and the} like from being blocked by the water permeable material and diffusing to the vicinity of the cation exchange membrane.

  Patent Document 3 proposes an electric deionized water production apparatus that suppresses the occurrence of reverse diffusion of carbonic acid by filling an anion exchange resin and a cation exchange resin in a concentration chamber. According to the apparatus of Patent Document 3, both the cation and the anion can move in the concentration chamber, so that the reverse diffusion of carbon dioxide can be made relatively small and the generation of scale can be reduced.

  In addition, the applicant previously stated that the macroporous pores overlap each other between the anion exchanger and the cation exchange membrane in the concentrating chamber, and the monolithic organic porous cation exchange has an open cell structure having an opening at the overlapped portion. An EDI with a body is proposed (Japanese Patent Application No. 2007-318125).

  However, in the organic porous cation exchanger described in Japanese Patent Application No. 2007-318125, the area of the skeleton part in the cross-sectional area is described as being in the range of 3 to 50% per unit cross-sectional area. For monoliths with a small pore volume of 5 ml / g or less, it is necessary to reduce the amount of water droplets in the water-in-oil emulsion, so the common opening becomes small, and the average diameter of the opening is substantially 20 μm or more. Cannot be manufactured. Therefore, the structure of the organic porous cation exchanger used in the present invention is different from that of the organic porous cation exchanger described in Japanese Patent Application No. 2007-318125. Details of the method for producing an organic porous cation exchanger described in Japanese Patent Application No. 2007-318125 are also disclosed in JP-A No. 2002-306976.

Japanese Patent Laid-Open No. 2001-225078 JP 2004-358440 A JP 2004-34004 A

  Accordingly, an object of the present invention is to provide an electric deionized water production apparatus and a deionized water production method capable of suppressing the occurrence of reverse diffusion of carbonic acid with a configuration different from the above and obtaining high-quality deionized water. There is to do.

The present invention provides a desalting chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side and filled with an ion exchanger, the cation exchange membrane, and the anion exchange. An electric deionized water production apparatus in which a concentration chamber provided on both sides of the demineralization chamber via a membrane and filled with an anion exchanger is disposed, the anion exchanger in the concentration chamber and the cation exchange membrane The monolithic organic porous cation exchanger is disposed between the two, and the monolithic organic porous cation exchanger has an average diameter of 30 to 300 μm in a state where the macroscopic pores overlap each other and the overlapping portion is wet with water. It is a continuous macropore structure serving as an opening, and has a total pore volume of 0.5 to 5 ml / g. In the SEM image of the cut surface of the continuous macropore structure (dried body), the skeleton part area that appears in the cross section , From 25 to 50% in image area (hereinafter, also referred to as "first monolithic ion exchanger".) It is intended to provide an electrodeionization water producing apparatus according to claim.

Further, the present invention provides a desalting chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side and filled with an ion exchanger, the cation exchange membrane, An electrical deionized water production apparatus in which a concentration chamber provided on both sides of the desalting chamber via an anion exchange membrane and filled with an anion exchanger is provided, the anion exchanger in the concentration chamber and the cation A monolithic organic porous cation exchanger is disposed between the exchange membrane, and the monolithic organic porous cation exchanger has an average diameter of 30 to 30 in which the macroscopic pores overlap each other and the overlapping portion is wet with water. 300 [mu] m is a continuous macropores structure comprising an opening of a total pore volume of 0.5 to 5 ml / g, the following steps; oil-soluble monomer not containing an ion exchange group, the mixture of surfactant and water A water-in-oil emulsion is prepared by stirring, and then the water-in-oil emulsion is polymerized to obtain a monolithic organic porous intermediate having a continuous macropore structure with a total pore volume of 5 to 16 ml / g , A vinyl monomer, a cross-linking agent having at least two vinyl groups in one molecule, a mixture of an organic solvent that dissolves the vinyl monomer and the cross-linking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer and a polymerization initiator The step II for preparing the mixture, the mixture obtained in the step II is allowed to stand, and the polymerization is carried out in the presence of the monolithic organic porous intermediate obtained in the step I to form a skeleton of the organic porous intermediate Obtained by performing Step III for obtaining a thick organic porous body having a thicker skeleton, and Step IV for introducing a cation exchange group into the thick organic porous body obtained in Step III. There is provided an electrodeionization water producing apparatus is shall.

Further, the present invention provides a desalting chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side and filled with an ion exchanger, the cation exchange membrane, An electrical deionized water production apparatus in which a concentration chamber provided on both sides of the desalting chamber via an anion exchange membrane and filled with an anion exchanger is provided, the anion exchanger in the concentration chamber and the cation A monolithic organic porous cation exchanger is disposed between the exchange membrane, and the monolithic organic porous cation exchanger has a cross-linking structural unit of 0.3 to 0.3 in all the structural units into which ion exchange groups are introduced. Consists of a three-dimensionally continuous skeleton having a thickness of 1 to 60 μm made of an aromatic vinyl polymer containing 5.0 mol% and three-dimensionally continuous pores having a diameter of 10 to 100 μm between the skeletons. A co-continuous structure, The present invention provides an apparatus for producing electrical deionized water having a total pore volume of 0.5 to 5 ml / g (hereinafter also referred to as “second monolith ion exchanger”).

Further, the present invention provides a desalting chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side and filled with an ion exchanger, the cation exchange membrane, Deionized water for producing deionized water using an electric deionized water production apparatus that is disposed on both sides of the demineralization chamber via an anion exchange membrane and is provided with a concentration chamber filled with an anion exchanger. In which the bubble-like macropores overlap each other between the anion exchanger in the concentrating chamber and the cation exchange membrane, and the overlapping portions are continuously formed as openings having an average diameter of 30 to 300 μm in a wet state of water. It is a macropore structure and has a total pore volume of 0.5 to 5 ml / g. In the SEM image of the cut surface of the continuous macropore structure (dry body), the skeletal area shown in the cross section is 25 to 25 in the image region. 50% There is provided a method for producing deionized water to place the monolithic organic porous cation exchanger that.

Further, the present invention provides a desalting chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side and filled with an ion exchanger, the cation exchange membrane, Deionized water for producing deionized water using an electric deionized water production apparatus that is disposed on both sides of the demineralization chamber via an anion exchange membrane and is provided with a concentration chamber filled with an anion exchanger. The method of manufacturing, wherein 0.3 to 5.0 mol% of a cross-linking structural unit is contained in all the structural units having an ion exchange group introduced between the anion exchanger in the concentration chamber and the cation exchange membrane. A co-continuous structure comprising a three-dimensionally continuous skeleton having a thickness of 1 to 60 μm and a three-dimensionally continuous pore having a diameter of 10 to 100 μm between the skeletons. The total pore volume is 0.5-5 ml / g There is provided a method for producing deionized water to place the monolithic organic porous cation exchanger.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the reverse diffusion of a carbonic acid can be suppressed and high quality deionized water can be obtained. In addition, the present invention can increase the strength of the monolithic organic porous cation exchanger.

It is a SEM image of the monolith in the 1st monolith ion exchanger. It is an EPMA image which showed the distribution state of the sulfur atom in the surface of the monolith of FIG. 2 is an EPMA image showing a distribution state of sulfur atoms in the cross-section (thickness) direction of the monolith of FIG. It is a figure which shows the correlation of the differential pressure | voltage coefficient of the reference example 11 and the reference examples 16-19, and the ion exchange capacity per volume. It is a manual transfer of the skeleton part that appears as a cross section of the SEM image of FIG. It is the figure which showed typically the co-continuous structure of the 2nd monolith ion exchanger. It is a SEM image of the monolith intermediate in a bicontinuous structure. It is a SEM image of the monolith cation exchanger which has a bicontinuous structure. It is the EPMA image which showed the distribution state of the sulfur atom in the surface of the monolith cation exchanger which has a bicontinuous structure. It is the EPMA image which showed the distribution state of the sulfur atom in the cross section (thickness) direction of the monolith cation exchanger which has a bicontinuous structure. It is a SEM image of the other monolith cation exchanger which has a bicontinuous structure. 4 is a SEM photograph of the organic porous material obtained in Reference Example 16. It is a schematic block diagram of the electrical deionized water manufacturing apparatus which concerns on this Embodiment. It is a disassembled perspective view which shows an example of a structure of the concentration chamber which concerns on this Embodiment. It is a schematic block diagram of the electrical deionized water manufacturing apparatus which concerns on other embodiment of this invention. It is a schematic block diagram which shows the test cell for measuring the amount of carbonic acid components which moves to a desalination chamber from a concentration chamber.

  The electric deionized water production apparatus according to the embodiment of the present invention is a deionization system in which an cation exchange membrane on one side and an anion exchange membrane on the other side are partitioned between an anode and a cathode and filled with an ion exchanger. A salt chamber and a concentration chamber provided on both sides of the desalting chamber through the cation exchange membrane and the anion exchange membrane and filled with an anion exchanger are arranged. Here, as long as the demineralization chamber of the electric deionized water production apparatus according to the present embodiment has the above configuration, for example, the cation exchange membrane and the anion A desalination chamber partitioned into two small desalination chambers by an intermediate ion exchange membrane positioned between the exchange membranes and configured to allow water to be treated to flow sequentially through the two small desalination chambers. There may be. If the desalting chamber divided into these two small desalting chambers is used, it becomes possible to efficiently perform desalting treatment of the water to be treated.

  Hereinafter, a desalting chamber partitioned into two small desalting chambers by an intermediate ion exchange membrane located between the cation exchange membrane and the anion exchange membrane will be described as an example.

  FIG. 13 is a schematic configuration diagram of an electric deionized water production apparatus according to this embodiment. In the electric deionized water production apparatus 1, the cation exchange membrane 10, the intermediate ion exchange membrane 12, and the anion exchange membrane 14 are alternately arranged apart from each other, and the intermediate ion exchange membrane 12, the anion exchange membrane 14, The first small desalination chambers d1, d3, d5 and the second small desalination chambers d2, d4, d6 partitioned by the cation exchange membrane 10 and the intermediate ion exchange membrane 12 are formed. The first small desalination chamber d1 and the second small desalination chamber d2 are the desalination chamber D1, the first small desalination chamber d3 and the second small desalination chamber d4 are the desalination chamber D2, and the first small desalination chamber d2. A desalting chamber D3 is formed by d5 and the second small desalting chamber d6. A portion formed by the anion exchange membrane 14 and the cation exchange membrane 10 located between the desalting chambers D1 and D2 and D2 and D3 is a concentration chamber 16 (16a, 16b) for flowing concentrated water. And These are sequentially arranged to form a desalting chamber D1, a concentrating chamber 16a, a desalting chamber D2, a concentrating chamber 16b, and a desalting chamber D3 from the left in FIG. In addition, the number of the desalting chambers and the concentration chambers in FIG. Further, the concentration chamber can be provided between the desalting chamber and an electrode chamber described later, if necessary.

  The first small desalting chambers d1, d3, and d5 shown in FIG. 13 are filled with the anion exchanger 20, and the second small desalting chambers d2, d4, and d6 are mixed ions of the anion exchanger and the cation exchanger. The exchanger 18 (hereinafter also simply referred to as “mixture 18”) is filled. In addition, the ion exchangers filled in the first small desalting chambers d1, d3, d5 and the second small desalting chambers d2, d4, 6 are not limited to the above, depending on the purpose of the desalting treatment. May be selected as appropriate.

  The intermediate ion exchange membrane 12 in the above embodiment is an anion exchange membrane, but is not particularly limited.

  The concentration chambers 16 a and 16 b are filled with an anion exchanger 22. By filling the concentration chambers 16a and 16b with the anion exchanger 22, it is possible to prevent carbon dioxide from diffusing on the surface of the cation exchange membrane 10 in the concentration chambers 16a and 16b and generating a hardness scale on the surface of the cation exchange membrane 10, Further, the presence of the high conductivity anion exchanger 22 can reduce the applied voltage.

  In addition, a monolithic organic porous cation exchanger 23 is disposed between the anion exchanger 22 and the cation exchange membrane 10 in the concentration chambers 16a and 16b. In the monolithic organic porous cation exchanger 23, the flow path of the concentrating chamber is formed by the macropores and the opening, or the flow path of the concentrating chamber is formed by co-continuous pores.

  FIG. 14 is an exploded perspective view showing an example of the configuration of the concentration chamber in the present embodiment. As shown in FIG. 14, in the concentration chambers 16a and 16b, a frame 25 is disposed between the anion exchange membrane 14 in the desalting chambers D1 and D2 and the cation exchange membrane 10 in another desalting chamber D2 and D3. The hollowed out portion of the frame body 25 is filled with the anion exchanger 22. A monolithic organic porous cation exchanger 23 is disposed between the frame 25 and the cation exchange membrane 10. The frame 25 and the anion exchange membrane 14, the frame 25 and the monolithic organic porous cation exchanger 23, the monolithic organic porous cation exchanger 23 and the cation exchange membrane 10 are sealed. In the present embodiment, another frame is disposed between the frame 25 and the cation exchange membrane 10, and the monolithic organic porous cation exchanger 23 is disposed in the hollowed portion of the frame. May be. Since the ion exchange membrane is usually relatively soft, when the anion exchange membrane 14 and the frame 25 are sealed, the anion exchange membrane 14 is curved and filled into the hollowed out portion of the frame 25. The packed bed of anion exchanger 22 tends to be non-uniform. In order to prevent this, a plurality of ribs (not shown) may be provided vertically in the space of the frame body 25. Although not shown in the figure, the frame 25 is provided with an inlet and an outlet of concentrated water.

  It is preferable that the desalting chambers D1, D2, and D3 have a configuration in which the frame body is used in the same manner as described above, and an ion exchanger is filled in a hollowed portion of the frame body. That is, a frame is disposed between the cation exchange membrane 10 and the intermediate ion exchange membrane 12, and between the intermediate ion exchange membrane 12 and the anion exchange membrane 14, and the ion exchanger is filled in the hollowed portion of each frame. Is done. Further, each frame, the cation exchange membrane 10, the intermediate ion exchange membrane 12, and the anion exchange membrane 14 are sealed.

  Spaces between both outer sides of the desalting chambers D1 and D3 at both ends and both electrodes (cathode 24, anode 26) are respectively used as electrode chambers 28 and 30, and electrode water (concentrated water in this embodiment) is provided here. Water is passed. The electrode chambers 28 and 30 may be filled with a cation exchanger, an anion exchanger, or the like as necessary. In the example of FIG. 13, the anion exchanger 32 is disposed in the electrode chamber 28 and the cation exchanger 34 is disposed in the electrode chamber 30, but this is not restrictive.

  In the electric deionized water production apparatus 1 of FIG. 13, the first inflow lines 36 through which the treated water flows are connected to the inlets of the first small demineralization chambers d1, d3, d5, respectively. A first outflow line 38 for flowing out the water to be treated from the outlets of the salt chambers d1, d3, d5 is a second for flowing the water to be treated into the inlets of the second small desalting chambers d2, d4, d6. It is connected to the inflow line 40. A second outflow line 42 through which the treated water flows out is connected to the outlets of the second small desalting chambers d2, d4, and d6, respectively. With the above configuration, the water to be treated is first supplied to the first small desalting chambers d1, d3, and d5 and desalted. And the to-be-processed water which passed 1st small desalination chamber d1, d3, d5 is supplied to 2nd small desalination chamber d2, d4, d6, is further desalted, and is discharged | emitted as treated water. The flow path of the water to be treated is not limited to the above. For example, the second anion exchanger 20 filled with the anion exchanger 20 from the second small desalting chambers d2, d4, d6 filled with the mixture 18 is used. The treated water may be passed through the small desalting chambers d1, d3, and d5.

  The concentrated water inflow line 48 is connected to the inlets of the concentrating chambers 16a and 16b, respectively, and the concentrated water outflow line 50 is connected to the outlets of the concentrating chambers 16a and 16b, respectively. The electrode water inflow line is the same line as the concentrated water inflow line 48 and is connected to the inlets of the electrode chambers 28 and 30, respectively. The electrode water outflow line is the same line as the concentrated water outflow line 50, and the electrode chambers 28, 30 Each is connected to 30 outlets. In the present embodiment, the electrode water inflow line and the concentrated water inflow line 48, the electrode water outflow line and the concentrated water outflow line 50 are the same line, but may be different lines. Moreover, although the solution made to flow in as concentrated water and electrode water is made to pass through as the same thing, it is not restricted to this, It is good also considering concentrated water and electrode water as a different solution.

  Moreover, in this embodiment, the flow direction of the water to be treated flowing into the first small desalination chambers d1, d3, d5 and the flow direction of the water to be treated flowing into the second small desalination chambers d2, d4, d6. Are both descending directions, and the flow direction of the concentrated water is the opposite upward direction, but is not limited thereto.

  An example of an operation method in the case of producing deionized water by the electric deionized water production apparatus 1 in the present embodiment will be described below. First, in a state where a direct current is passed between the cathode 24 and the anode 26, water to be treated is introduced from the first inflow line 36 and concentrated water is introduced from the concentrated water inflow line 48. The water to be treated that flows from the first inflow line 36 flows through the first small desalting chambers d1, d3, and d5 and passes through the packed bed of the anion exchanger 20, so that it is carbonated (free carbonic acid, bicarbonate ions, carbonate ions). ), Anions such as silica are removed. Furthermore, the water to be treated that has passed through the first outflow line 38 of the first small desalination chambers d1, d3, d5 flows through the second inflow line 40 of the second small desalination chambers d2, d4, d6, and the mixture 18. When passing through the packed bed, cations and anions are removed, and treated water (deionized water) is obtained from the second outflow line 42. Further, the concentrated water flowing in from the concentrated water inflow line 48 flows through the concentration chambers 16a and 16b, receives ions moving through the cation exchange membrane 10 and the anion exchange membrane 14, and is used as concentrated water obtained by concentrating the ions. It flows out from the concentrated water outflow line 50. Furthermore, the electrode water flowing in from the concentrated water inflow line 48 (electrode water inflow line) flows out from the concentrated water outflow line 50 (electrode water outflow line). By the above operation, treated water (deionized water) from which impurity ions in the water to be treated have been removed is obtained.

Carbonic acid (free carbonic acid, bicarbonate ion, carbonate ion) trapped by the anion exchanger 20 in the first small desalting chambers d1, d3, d5 flowing in first is trapped by the hydroxide ion or the anion exchanger 20. It passes through the anion exchange membrane 14 on the anode side together with the other anion components thus formed, and moves to the concentration chambers 16a and 16b. The anion exchanger 22 in the concentrating chambers 16a and 16b becomes an HCO _{3 type} anion exchanger by the carbon dioxide that has moved. Unlike the present embodiment, in the state where the monolithic organic porous cation exchanger 23 is not disposed between the anion exchanger 22 and the cation exchange membrane 10 in the concentration chambers 16a and 16b, the HCO _{3 type} When an electric current flows through the anion exchanger, HCO ₃ ⁻ (and CO ₃ ²⁻ ) is attracted to the vicinity of the cation exchange membrane 10 by an electric field, but cannot pass through the cation exchange membrane 10, and in the vicinity of the cation exchange membrane 10. Concentrated. As a result, the HCO ₃ ⁻ (and CO ₃ ²⁻ ) suddenly moves between the concentration chambers 16 a and 16 b (rich side) and the first small desalting chambers d ₃ and d 5 (lean side) across the cation exchange membrane 10. A concentration gradient occurs. Further, since hydrogen ions permeate from the cation exchange membrane 10, the pH in the vicinity of the cation exchange membrane 10 in the concentration chambers 16a and 16b is lowered. Then, water and carbon dioxide (CO ₂ ) are generated, and a high-concentration carbon dioxide-containing aqueous solution layer is formed in the vicinity of the cation exchange membrane 10, and the carbon dioxide permeates through the cation exchange membrane 10 by diffusion and becomes the second small desalting. It moves (reverse diffusion) to the chambers d4 and d6. As a result, the final treated water discharged from the second small desalting chambers d4 and d6 is contaminated with carbonic acid.

  On the other hand, in the present embodiment, since the monolithic organic porous cation exchanger 23 is disposed between the anion exchanger 22 and the cation exchange membrane 10 in the concentration chambers 16a and 16b, the concentration chamber 16a. , 16 b is not in contact with the cation exchange membrane 10. Therefore, the high-concentration carbon dioxide-containing aqueous solution layer is formed on the surface or inside of the monolithic organic porous cation exchanger 23 that is separated from the cation exchange membrane 10 and mainly in contact with the anion exchanger 22. In addition, since the macropores and openings or pores of the monolithic organic porous cation exchanger 23 are channels through which concentrated water passes, the carbon dioxide gas on the surface or inside of the monolithic organic porous cation exchanger 23 is Before coming into contact with the cation exchange membrane 10, it flows out of the concentration chambers 16a and 16b together with the concentrated water. Moreover, even if carbon dioxide gas on the surface or inside of the monolithic organic porous cation exchanger 23 reaches the cation exchange membrane 10, it is diluted (lowered in concentration) in the monolithic organic porous cation exchanger 23. Therefore, the amount of carbon dioxide that permeates the cation exchange membrane 10 is greatly reduced.

  In addition, since the monolithic organic porous cation exchanger 23 of the present embodiment is dispersed with ion exchange groups (cation exchange groups), the monolithic organic porous body without ion exchange groups is concentrated in the concentration chamber 16a. The electrical resistance of the electric deionized water production apparatus 1 can be made lower than that disposed between the anion exchanger 22 and the cation exchange membrane 10 in 16b. The monolithic organic porous cation exchanger 23 has a higher filling rate than other cation exchangers such as other mesh-like materials, nonwoven fabrics, and woven fabrics. The electric resistance of the electric deionized water production apparatus 1 can be made lower than that of disposing a porous cation exchanger.

  In the configuration in which the water to be treated is contacted in the order of the anion exchanger filled in the first small desalting chamber to the mixture (anion exchanger and cation exchanger) filled in the second small desalting chamber, When the reverse diffusion phenomenon occurs, the carbonic acid moves to the second small desalting chamber of the final treatment, so that the treated water is easily contaminated with carbonic acid. However, by disposing the monolithic organic porous cation exchanger between the anion exchanger and the cation exchanger in the concentration chamber, the reverse diffusion phenomenon of carbon dioxide is suppressed. Carbon dioxide contamination can be prevented. In addition, the mixture filled in the desalting chamber can remove both anions and cations, and high-quality deionized water can be obtained.

  The monolithic organic porous cation exchanger used in the electric deionized water production apparatus of the present invention is a “first monolith ion exchanger” or a “second monolith ion exchanger”. In the present specification, “monolithic organic porous body” is simply “monolith”, “monolithic organic porous ion exchanger” is simply “monolith ion exchanger”, and “monolithic organic porous intermediate”. Is also simply referred to as “monolith intermediate”.

<Description of the first monolith ion exchanger>
The first monolith ion exchanger is obtained by introducing a cation exchange group into the monolith, and the bubble-like macropores are overlapped with each other, and the overlapping portion has an average diameter of 30 to 300 μm in a water wet state, preferably It is a continuous macropore structure which becomes an opening (mesopore) of 30 to 200 μm, particularly 35 to 150 μm. The average diameter of the opening of the monolith ion exchanger is larger than the average diameter of the opening of the monolith because the entire monolith swells when a cation exchange group is introduced into the monolith. If the average diameter of the openings is less than 30 μm, the pressure loss of the concentrated water increases, and it may be difficult to drain the carbon dioxide gas generated in the monolith ion exchanger together with the concentrated water. On the other hand, if the average diameter of the openings is too large, the contact between the fluid and the monolith ion exchanger becomes insufficient, and as a result, the ion exchange characteristics deteriorate. In the present invention, the average diameter of the opening of the monolith intermediate in the dry state, the average diameter of the opening of the monolith in the dry state, and the average diameter of the opening of the monolith ion exchanger in the dry state are values measured by a mercury intrusion method. It is. Further, the average diameter of the openings of the monolith ion exchanger in the wet state is a value calculated by multiplying the average diameter of the openings of the monolith ion exchanger in the dry state by the swelling rate. Specifically, the water-wet monolith ion exchanger has a diameter of x1 (mm), the water-wet monolith ion exchanger is dried, and the resulting dried monolith ion exchanger has a diameter of y1 ( mm), and the average diameter of the opening of the monolith ion exchanger in the dry state measured by the mercury intrusion method was z1 (μm), the average diameter of the opening of the monolith ion exchanger in the water wet state ( μm) is calculated by the following formula: “average diameter of openings of monolith ion exchanger in water wet state (μm) = z1 × (x1 / y1)”. In addition, the average diameter of the opening of the dried monolith before introduction of the ion exchange group, and the swelling ratio of the monolith ion exchanger in the water wet state relative to the dried monolith when the ion exchange group is introduced into the dried monolith. In this case, the average diameter in the water-wet state of the pores of the monolith ion exchanger can also be calculated by multiplying the average diameter of the opening of the monolith in the dry state by the swelling rate.

  In the first monolith ion exchanger, in the SEM image of the cut surface of the continuous macropore structure, the skeleton part area appearing in the cross section is 25 to 50%, preferably more than 25 and 45% or less in the image region. When the area of the skeleton part shown in the cross section is less than 25% in the image region, the skeleton becomes a thin skeleton, and the strength of the monolith ion exchanger may be reduced. When the area exceeds 50%, the concentrated water flowing through the monolith ion exchanger. In some cases, it becomes difficult to drain the carbon dioxide gas generated in the monolith ion exchanger together with the concentrated water. In addition, the monolith described in Japanese Patent Application No. 2007-318125 has a limit to the blending ratio in order to ensure a common opening even if the blending ratio of the oil phase part with respect to water is actually increased and the skeleton part is thickened. Yes, the maximum value of the skeleton part area appearing in the cross section cannot exceed 25% in the image region.

  The conditions for obtaining the SEM image may be any conditions as long as the skeleton part that appears in the cross section of the cut surface appears clearly. For example, the magnification is 100 to 600, and the photographic area is about 150 mm × 100 mm. SEM observation is preferably performed on three or more images, preferably five or more images, taken at arbitrary locations on an arbitrary cut surface of the monolith excluding subjectivity and at different locations. The monolith to be cut is in a dry state for use in an electron microscope. The skeleton part of the cut surface in the SEM image will be described with reference to FIGS. FIG. 5 is a transcribed skeleton that appears as a cross section of the SEM photograph of FIG. 1 and FIG. 5, what is generally indeterminate in shape and shown in cross section is the “skeleton part (reference numeral 82)” in the present invention, the circular hole shown in FIG. 1 is an opening (mesopore), and A relatively large curvature or curved surface is a macropore (reference numeral 83 in FIG. 5). The skeleton part area shown in the cross section of FIG. 5 is 28% in the rectangular photographic region 81. Thus, the skeleton can be clearly determined.

  In the SEM photograph, the method for measuring the area of the skeletal part appearing in the cross section of the cut surface is not particularly limited, and after specifying the skeletal part by performing known computer processing or the like, calculation by automatic calculation by a computer or manual calculation A method is mentioned. The manual calculation includes a method in which an indefinite shape is replaced with an aggregate such as a quadrangle, a triangle, a circle, or a trapezoid, and the areas are obtained by stacking them.

  The first monolith ion exchanger has a total pore volume of 0.5 to 5 ml / g, preferably 0.8 to 4 ml / g. When the total pore volume is less than 0.5 ml / g, the pressure loss of the concentrated water flowing through the monolith ion exchanger increases, and it becomes difficult to drain the carbon dioxide gas generated in the monolith ion exchanger together with the concentrated water. There is a case. On the other hand, if the total pore volume exceeds 5 ml / g, the strength of the monolith ion exchanger is decreased, and the electrical resistance of the electric deionized water production apparatus is increased. In the present invention, the total pore volume of the monolith (monolith intermediate, monolith, monolith ion exchanger) is a value measured by a mercury intrusion method. In addition, the total pore volume of the monolith (monolith intermediate, monolith, monolith ion exchanger) is the same both in the dry state and in the water wet state.

  In addition, the pressure loss at the time of making water permeate | transmit the 1st monolith ion exchanger is the pressure loss at the time of letting water flow through the column filled with 1 m of the porous body at a water flow rate (LV) of 1 m / h (hereinafter referred to as “pressure loss”). , “Differential pressure coefficient”), it is preferably in the range of 0.001 to 0.1 MPa / m · LV, more preferably 0.001 to 0.05 MPa / m · LV.

  The first monolith ion exchanger has an ion exchange capacity of 0.4 to 5 mg equivalent / ml per volume in a water-wet state. In the monolithic organic porous ion exchanger having an open cell structure different from the present invention as described in Japanese Patent Application No. 2007-318125, in order to achieve a low pressure loss that is practically required, As the total pore volume increases, the ion exchange capacity per volume decreases.If the total pore volume is reduced to increase the exchange capacity per volume, the total pore volume increases. There was a drawback that the pressure loss increased because the aperture was reduced. On the other hand, the monolith ion exchanger of the present invention can further increase the aperture diameter and thicken the skeleton of the continuous macropore structure (thicken the skeleton wall), so that the pressure loss during permeation can be reduced. The amount of concentrated water that is kept low and passes through the monolith ion exchanger can be increased. The ion exchange capacity per weight of the monolith ion exchanger of the present invention is not particularly limited. However, since the ion exchange groups are uniformly introduced to the surface of the porous body and the inside of the skeleton, 3 to 5 mg equivalent / g It is. The ion exchange capacity of a porous body in which ion exchange groups are introduced only on the surface cannot be determined unconditionally depending on the type of the porous body or ion exchange groups, but is at most 500 μg equivalent / g.

  In the first monolith ion exchanger, the material constituting the skeleton of the continuous macropore structure is an organic polymer material having a crosslinked structure. Although the crosslinking density of the polymer material is not particularly limited, it contains 0.3 to 50 mol%, preferably 0.3 to 5 mol% of crosslinked structural units with respect to all structural units constituting the polymer material. It is preferable. If the cross-linking structural unit is less than 0.3 mol%, it is not preferable because the mechanical strength is insufficient. On the other hand, if it exceeds 50 mol%, embrittlement of the porous body proceeds and flexibility is lost. In particular, in the case of an ion exchanger, the amount of ion exchange groups introduced is decreased, which is not preferable. The type of the polymer material is not particularly limited, and examples thereof include aromatic vinyl polymers such as polystyrene, poly (α-methylstyrene), polyvinyl toluene, polyvinyl benzyl chloride, polyvinyl biphenyl, and polyvinyl naphthalene; polyolefins such as polyethylene and polypropylene; Poly (halogenated polyolefin) such as vinyl chloride and polytetrafluoroethylene; Nitrile-based polymer such as polyacrylonitrile; Cross-linking weight of (meth) acrylic polymer such as polymethyl methacrylate, polyglycidyl methacrylate, and polyethyl acrylate Coalesce is mentioned. The polymer may be a polymer obtained by copolymerizing a single vinyl monomer and a crosslinking agent, a polymer obtained by polymerizing a plurality of vinyl monomers and a crosslinking agent, or a blend of two or more types of polymers. It may be what was done. Among these organic polymer materials, the cross-linking weight of the aromatic vinyl polymer is high due to the ease of forming a continuous macropore structure, the ease of introducing ion-exchange groups and the high mechanical strength, and the high stability to acids and alkalis. A styrene-divinylbenzene copolymer and a vinylbenzyl chloride-divinylbenzene copolymer are particularly preferable materials.

  Examples of the ion exchange group of the first monolith ion exchanger include cation exchange groups such as a sulfonic acid group, a carboxylic acid group, an iminodiacetic acid group, a phosphoric acid group, and a phosphoric acid ester group.

  In the first monolith ion exchanger, the introduced ion exchange groups are uniformly distributed not only on the surface of the porous body but also within the skeleton of the porous body. Here, “ion exchange groups are uniformly distributed” means that the distribution of ion exchange groups is uniformly distributed on the surface and inside the skeleton in the order of at least μm. The distribution of ion exchange groups can be confirmed relatively easily by using EPMA or the like. In addition, if the ion exchange groups are uniformly distributed not only on the surface of the monolith but also within the skeleton of the porous body, the physical and chemical properties of the surface and the interior can be made uniform, so that the swelling and shrinkage can be achieved. The durability against is improved.

(Method for producing first monolithic ion exchanger)
The first monolith ion exchanger is prepared by preparing a water-in-oil emulsion by stirring a mixture of oil-soluble monomer, surfactant and water that does not contain ion-exchange groups, and then polymerizing the water-in-oil emulsion. Step I for obtaining a monolithic organic porous intermediate having a continuous macropore structure having a total pore volume of 5 to 16 ml / g, a vinyl monomer, a crosslinking agent having at least two vinyl groups in one molecule, a vinyl monomer, Step II for preparing a mixture comprising an organic solvent and a polymerization initiator that dissolves the cross-linking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer. The mixture obtained in Step II is allowed to stand still and in Step I. Polymerization is performed in the presence of the obtained monolithic organic porous intermediate to obtain a thick organic porous body having a skeleton thicker than the skeleton of the organic porous intermediate. It is obtained by performing the IV step of introducing a cation exchange group into the thick organic porous material obtained in the step III.

  In the first method for producing a monolithic ion exchanger, the step I may be performed in accordance with the method described in JP-A-2002-306976.

  In the production of the monolith intermediate of step I, the oil-soluble monomer that does not contain an ion exchange group includes, for example, an ion exchange group such as a carboxylic acid group, a sulfonic acid group, and a quaternary ammonium group, and is soluble in water. Low and lipophilic monomers may be mentioned. Preferable examples of these monomers include styrene, α-methylstyrene, vinyl toluene, vinyl benzyl chloride, divinyl benzene, ethylene, propylene, isobutene, butadiene, ethylene glycol dimethacrylate, and the like. These monomers can be used alone or in combination of two or more. However, a crosslinkable monomer such as divinylbenzene or ethylene glycol dimethacrylate is selected as at least one component of the oil-soluble monomer, and the content thereof is 0.3 to 50 mol%, preferably 0.3 to the total oil-soluble monomer. 5 mol% is preferable in that the mechanical strength necessary for introducing a large amount of ion-exchange groups in a later step can be obtained.

  The surfactant is not particularly limited as long as it can form a water-in-oil (W / O) emulsion when an oil-soluble monomer containing no ion exchange group and water are mixed, and sorbitan monooleate, Nonionic surfactants such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan trioleate, polyoxyethylene nonylphenyl ether, polyoxyethylene stearyl ether, polyoxyethylene sorbitan monooleate; potassium oleate Anionic surfactants such as sodium dodecylbenzenesulfonate and dioctyl sodium sulfosuccinate; cationic surfactants such as distearyldimethylammonium chloride; amphoteric surfactants such as lauryldimethylbetaine can be used . These surfactants can be used alone or in combination of two or more. The water-in-oil emulsion refers to an emulsion in which an oil phase is a continuous phase and water droplets are dispersed therein. The amount of the surfactant added may vary depending on the type of oil-soluble monomer and the size of the target emulsion particles (macropores), but it cannot be generally stated, but the total amount of oil-soluble monomer and surfactant Can be selected within a range of about 2 to 70%.

  In Step I, a polymerization initiator may be used as necessary when forming a water-in-oil emulsion. As the polymerization initiator, a compound that generates radicals by heat and light irradiation is preferably used. The polymerization initiator may be water-soluble or oil-soluble. For example, azobisisobutyronitrile, azobiscyclohexanenitrile, azobiscyclohexanecarbonitrile, benzoyl peroxide, potassium persulfate, ammonium persulfate, Examples thereof include hydrogen oxide-ferrous chloride, sodium persulfate-sodium acid sulfite, and tetramethylthiuram disulfide.

  The mixing method for mixing the oil-soluble monomer not containing an ion exchange group, a surfactant, water, and a polymerization initiator to form a water-in-oil emulsion is not particularly limited. Method of mixing at once, oil-soluble monomer, surfactant and oil-soluble polymerization initiator oil-soluble component and water or water-soluble polymerization initiator water-soluble component separately and uniformly dissolved, A method of mixing the components can be used. There is no particular limitation on the mixing apparatus for forming the emulsion, and a normal mixer, homogenizer, high-pressure homogenizer, or the like can be used, and an appropriate apparatus may be selected to obtain the desired emulsion particle size. Moreover, there is no restriction | limiting in particular about mixing conditions, The stirring rotation speed and stirring time which can obtain the target emulsion particle size can be set arbitrarily.

  The monolith intermediate obtained in Step I has a continuous macropore structure. When this coexists in the polymerization system, a porous structure having a thick skeleton is formed using the structure of the monolith intermediate as a template. The monolith intermediate is an organic polymer material having a crosslinked structure. Although the crosslinking density of the polymer material is not particularly limited, it contains 0.3 to 50 mol%, preferably 0.3 to 5 mol% of crosslinked structural units with respect to all the structural units constituting the polymer material. Is preferred. When the cross-linking structural unit is less than 0.3 mol%, the mechanical strength is insufficient, which is not preferable. In particular, when the total pore volume is as large as 10 to 16 ml / g, in order to maintain a continuous macropore structure, it is preferable to contain 2 mol% or more of cross-linked structural units. On the other hand, if it exceeds 50 mol%, the porous body becomes brittle and the flexibility is lost.

  The type of the polymer material of the monolith intermediate is not particularly limited, and examples thereof include the same materials as the monolith polymer material described above. Thereby, the same polymer can be formed in the skeleton of the monolith intermediate, and the skeleton can be thickened to obtain a monolith having a uniform skeleton structure.

  The total pore volume of the monolith intermediate is 5 to 16 ml / g, preferably 6 to 16 ml / g. If the total pore volume is too small, the total pore volume of the monolith obtained after polymerizing the vinyl monomer becomes too small, and the pressure loss of concentrated water increases, which is not preferable. On the other hand, if the total pore volume is too large, the structure of the monolith obtained after polymerizing the vinyl monomer deviates from the continuous macropore structure, which is not preferable. In order to make the total pore volume of the monolith intermediate within the above numerical range, the ratio of the monomer and water may be about 1: 5 to 1:20.

  Moreover, the average diameter of the opening (mesopore) which is an overlap part of a macropore and a macropore is 20-200 micrometers in a monolith intermediate body in a dry state. If the average diameter of the openings is less than 20 μm, the opening diameter of the monolith obtained after polymerizing the vinyl monomer becomes small, and the pressure loss during permeation of concentrated water becomes large, which is not preferable. On the other hand, if it exceeds 200 μm, the opening diameter of the monolith obtained after polymerizing the vinyl monomer becomes too large, and the strength of the monolith ion exchanger decreases, which is not preferable. Monolith intermediates preferably have a uniform structure with uniform macropore size and aperture diameter, but are not limited to this, and the uniform structure is dotted with nonuniform macropores larger than the size of the uniform macropore. You may do.

  Step II consists of a vinyl monomer, a crosslinking agent having at least two vinyl groups in one molecule, an organic solvent and a polymerization initiator that dissolves the vinyl monomer and the crosslinking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer. A step of preparing a mixture of In addition, there is no order of I process and II process, II process may be performed after I process, and I process may be performed after II process.

  The vinyl monomer used in step II is not particularly limited as long as it is a lipophilic vinyl monomer containing a polymerizable vinyl group in the molecule and having high solubility in an organic solvent, but is allowed to coexist in the polymerization system. It is preferred to select a vinyl monomer that produces the same or similar polymer material as the monolith intermediate. Specific examples of these vinyl monomers include aromatic vinyl monomers such as styrene, α-methylstyrene, vinyl toluene, vinyl benzyl chloride, vinyl biphenyl and vinyl naphthalene; α-olefins such as ethylene, propylene, 1-butene and isobutene; Diene monomers such as butadiene, isoprene and chloroprene; halogenated olefins such as vinyl chloride, vinyl bromide, vinylidene chloride and tetrafluoroethylene; nitrile monomers such as acrylonitrile and methacrylonitrile; vinyl such as vinyl acetate and vinyl propionate Esters: methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-methacrylic acid 2- Hexyl, cyclohexyl methacrylate, benzyl methacrylate, and (meth) acrylic monomer of glycidyl methacrylate. These monomers can be used alone or in combination of two or more. The vinyl monomer suitably used in the present invention is an aromatic vinyl monomer such as styrene or vinyl benzyl chloride.

  The added amount of these vinyl monomers is 3 to 40 times, preferably 4 to 30 times, by weight with respect to the monolith intermediate coexisting during polymerization. If the amount of vinyl monomer added is less than 3 times that of the porous material, the resulting monolith skeleton (the thickness of the monolith skeleton wall) cannot be increased, and the adsorption capacity per volume and the volume after introduction of ion-exchange groups. Since the ion exchange capacity per unit becomes small, it is not preferable. On the other hand, when the addition amount of vinyl monomer exceeds 40 times, the opening diameter becomes small, and the pressure loss at the time of permeation of concentrated water increases, which is not preferable.

  As the crosslinking agent used in step II, a crosslinking agent containing at least two polymerizable vinyl groups in the molecule and having high solubility in an organic solvent is preferably used. Specific examples of the crosslinking agent include divinylbenzene, divinylnaphthalene, divinylbiphenyl, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, butanediol diacrylate, and the like. These crosslinking agents can be used singly or in combination of two or more. Preferred cross-linking agents are aromatic polyvinyl compounds such as divinylbenzene, divinylnaphthalene and divinylbiphenyl because of their high mechanical strength and stability to hydrolysis. The amount of the crosslinking agent used is preferably 0.3 to 50 mol%, particularly 0.3 to 5 mol%, based on the total amount of the vinyl monomer and the crosslinking agent. When the amount of the crosslinking agent used is less than 0.3 mol%, the mechanical strength of the monolith is insufficient, which is not preferable. On the other hand, if it exceeds 50 mol%, the monolith becomes more brittle and the flexibility is lost, and the amount of ion-exchange groups introduced decreases, which is not preferable. In addition, it is preferable to use the said crosslinking agent usage-amount so that it may become substantially equal to the crosslinking density of the monolith intermediate body coexisted at the time of vinyl monomer / crosslinking agent polymerization. If the amounts used of both are too large, the crosslink density distribution is biased in the produced monolith, and cracks are likely to occur during the ion exchange group introduction reaction.

  The organic solvent used in Step II is an organic solvent that dissolves the vinyl monomer and the crosslinking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer. In other words, it is a poor solvent for the polymer formed by polymerization of the vinyl monomer. . Since the organic solvent varies greatly depending on the type of vinyl monomer, it is difficult to list general specific examples. For example, when the vinyl monomer is styrene, the organic solvent includes methanol, ethanol, propanol, butanol, Alcohols such as hexanol, cyclohexanol, octanol, 2-ethylhexanol, decanol, dodecanol, ethylene glycol, propylene glycol, tetramethylene glycol, glycerin; diethyl ether, ethylene glycol dimethyl ether, cellosolve, methyl cellosolve, butyl cellosolve, polyethylene glycol, polypropylene Chain (poly) ethers such as glycol and polytetramethylene glycol; hexane, heptane, octane, isooctane, decane, dode Chain saturated hydrocarbons such as down, ethyl acetate, isopropyl acetate, cellosolve acetate, esters such as ethyl propionate. Moreover, even if it is a good solvent of polystyrene like a dioxane, THF, and toluene, when it is used with the said poor solvent and the usage-amount is small, it can be used as an organic solvent. These organic solvents are preferably used so that the concentration of the vinyl monomer is 30 to 80% by weight. If the amount of the organic solvent used deviates from the above range and the vinyl monomer concentration is less than 30% by weight, the polymerization rate is lowered, or the monolith structure after polymerization deviates from the range of the present invention. On the other hand, if the vinyl monomer concentration exceeds 80% by weight, the polymerization may run away, which is not preferable.

  As the polymerization initiator, a compound that generates radicals by heat and light irradiation is preferably used. The polymerization initiator is preferably oil-soluble. Specific examples of the polymerization initiator used in the present invention include 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis ( 2-methylbutyronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2′-azobisisobutyrate, 4,4′-azobis (4-cyanovaleric acid) 1,1′-azobis (cyclohexane-1-carbonitrile), benzoyl peroxide, lauroyl peroxide, potassium persulfate, ammonium persulfate, tetramethylthiuram disulfide and the like. The amount of the polymerization initiator used varies greatly depending on the type of monomer, polymerization temperature, etc., but can be used in a range of about 0.01 to 5% with respect to the total amount of vinyl monomer and crosslinking agent.

  In step III, the mixture obtained in step II is allowed to stand and polymerize in the presence of the monolith intermediate obtained in step I to obtain a thick monolith having a skeleton thicker than the skeleton of the monolith intermediate. It is a process to obtain. The monolith intermediate used in the step III plays a very important role in creating the monolith having the novel structure of the present invention. As disclosed in JP-A-7-501140 and the like, when a vinyl monomer and a crosslinking agent are allowed to stand in a specific organic solvent in the absence of a monolith intermediate, a particle aggregation type monolithic organic porous material is obtained. The body is obtained. On the other hand, when a monolith intermediate having a continuous macropore structure is present in the polymerization system as in the present invention, the structure of the monolith after polymerization changes dramatically, the particle aggregation structure disappears, and the above-mentioned thick monolith is lost. Is obtained. The reason for this has not been elucidated in detail, but in the absence of a monolith intermediate, the cross-linked polymer produced by polymerization precipitates and precipitates in the form of particles, while a particle aggregate structure is formed. When a porous body (intermediate) is present in the system, the vinyl monomer and the cross-linking agent are adsorbed or distributed from the liquid phase to the skeleton of the porous body, and polymerization proceeds in the porous body to obtain a thick skeleton monolith. It is thought that. Although the opening diameter is narrowed by the progress of the polymerization, since the total pore volume of the monolith intermediate is large, an appropriate opening diameter can be obtained even if the skeleton becomes thick.

  The internal volume of the reaction vessel is not particularly limited as long as it is large enough to allow the monolith intermediate to exist in the reaction vessel. When the monolith intermediate is placed in the reaction vessel, there is a gap around the monolith in plan view. Or a monolith intermediate in the reaction vessel with no gap. Of these, the thick monolith after polymerization is not pressed from the inner wall of the container and enters the reaction container without any gap, and the monolith is not distorted, and the reaction raw materials are not wasted and efficient. Even when the internal volume of the reaction vessel is large and there are gaps around the monolith after polymerization, the vinyl monomer and the crosslinking agent are adsorbed and distributed on the monolith intermediate, so the gaps in the reaction vessel A particle aggregate structure is not generated in the portion.

  In step III, the monolith intermediate is placed in a reaction vessel impregnated with the mixture (solution). As described above, the blending ratio of the mixture obtained in Step II and the monolith intermediate is 3 to 40 times by weight, preferably 4 to 30 times by weight, relative to the monolith intermediate. It is suitable to mix. Thereby, it is possible to obtain a monolith having a thick skeleton while having an appropriate opening diameter. In the reaction vessel, the vinyl monomer and the crosslinking agent in the mixture are adsorbed and distributed on the skeleton of the monolith intermediate that has been allowed to stand, and polymerization proceeds in the skeleton of the monolith intermediate.

  Various polymerization conditions can be selected depending on the type of monomer and the type of initiator. For example, when 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), benzoyl peroxide, lauroyl peroxide, potassium persulfate, etc. are used as initiators In a sealed container under an inert atmosphere, heat polymerization may be performed at 30 to 100 ° C. for 1 to 48 hours. By heat polymerization, the vinyl monomer adsorbed and distributed on the skeleton of the monolith intermediate and the cross-linking agent are polymerized in the skeleton to thicken the skeleton. After completion of the polymerization, the contents are taken out and extracted with a solvent such as acetone for the purpose of removing unreacted vinyl monomer and organic solvent to obtain a thick monolith.

  Next, the method of introducing a cation exchange group after producing a monolith by the above method is preferable in that the porous structure of the resulting monolith cation exchanger can be strictly controlled.

  There is no restriction | limiting in particular as a method of introduce | transducing a cation exchange group into the said monolith, Well-known methods, such as a polymer reaction and graft polymerization, can be used. For example, as a method of introducing a sulfonic acid group, if the monolith is a styrene-divinylbenzene copolymer, etc., a method of sulfonation using chlorosulfuric acid, concentrated sulfuric acid or fuming sulfuric acid; A method of grafting a sodium styrenesulfonate or acrylamido-2-methylpropanesulfonic acid by introducing a mobile group into the skeleton surface or inside the skeleton; Similarly, after graft polymerization of glycidyl methacrylate, a sulfonic acid group is introduced by functional group conversion. And the like. Among these methods, as for the method of introducing sulfonic acid groups, the method of introducing sulfonic acid groups into styrene-divinylbenzene copolymer using chlorosulfuric acid can introduce cation exchange groups uniformly and quantitatively. This is preferable. Examples of ion exchange groups to be introduced include cation exchange groups such as carboxylic acid groups, iminodiacetic acid groups, sulfonic acid groups, phosphoric acid groups, and phosphoric acid ester groups.

  Since the cation exchange group is introduced into the thick monolith, the first monolith ion exchanger swells greatly, for example, 1.4 to 1.9 times as thick as the monolith. That is, the degree of swelling is much greater than that obtained by introducing an ion exchange group into a conventional monolith described in JP-A-2002-306976. For this reason, even if the opening diameter of the thick monolith is small, the opening diameter of the monolith ion exchanger generally increases at the above magnification. In addition, the total pore volume does not change even when the opening diameter increases due to swelling. Therefore, the first monolith ion exchanger has a high mechanical strength because it has a thick bone skeleton despite the remarkably large opening diameter.

<Description of Second Monolith Ion Exchanger>
The second monolith ion exchanger is a tertiary having a thickness of 1 to 60 μm made of an aromatic vinyl polymer containing 0.3 to 5.0 mol% of a crosslinked structural unit among all the structural units into which ion exchange groups are introduced. A co-continuous structure comprising an originally continuous skeleton and three-dimensionally continuous pores having a diameter of 10 to 100 μm between the skeletons, and the total pore volume is 0.5 to 5 ml / g Yes, the ion exchange capacity per volume in a wet state of water is 0.3 to 5 mg equivalent / ml, and the cation exchange groups are uniformly distributed in the porous ion exchanger.

  The second monolith ion exchanger has a three-dimensional continuous skeleton having an average thickness of 1 to 60 μm, preferably 3 to 58 μm in a water-wet state in which ion-exchange groups are introduced, and an average diameter between the skeletons. It is a co-continuous structure composed of three-dimensionally continuous pores of 10 to 100 μm, preferably 15 to 90 μm, particularly 20 to 80 μm in a wet state. That is, as shown in the schematic diagram of FIG. 6, the co-continuous structure is a structure 90 in which a continuous skeleton phase 91 and a continuous vacancy phase 92 are intertwined and both are three-dimensionally continuous. The continuous vacancies 92 have higher continuity of the vacancies and are not biased in size compared to the conventional open-cell type monolith or particle aggregation type monolith, so that extremely uniform ion adsorption behavior can be achieved. Moreover, since the skeleton is thick, the mechanical strength is high.

  The skeleton thickness and pore diameter of the second monolith ion exchanger are larger than the monolith skeleton thickness and pore diameter because the entire monolith swells when an ion exchange group is introduced into the monolith. It becomes. These continuous pores have higher continuity of pores and are not biased in size compared to conventional open-cell monolithic organic porous ion exchangers and particle-aggregated monolithic organic porous ion exchangers. Therefore, extremely uniform ion adsorption behavior can be achieved. When the diameter of the three-dimensionally continuous pores is less than 10 μm, the pressure loss during the permeation of the concentrate increases, making it difficult to drain the carbon dioxide generated in the monolith ion exchanger together with the concentrated water. If the thickness exceeds 100 μm, the strength may decrease, or the filling rate may decrease and the electrical resistance of the electrical deionized water production apparatus may increase.

  The average diameter of the pores of the above-mentioned continuous structure in the water wet state is a value calculated by multiplying the average diameter of the pores of the monolith ion exchanger in the dry state measured by a known mercury intrusion method and the swelling ratio. It is. Specifically, the water-wet monolith ion exchanger has a diameter of x2 (mm), and the water-wet monolith ion exchanger is dried, and the resulting dried monolith ion exchanger has a diameter of y2 ( mm), and the average diameter of the pores when the dried monolith ion exchanger was measured by the mercury intrusion method was z2 (μm), the pores of the monolith ion exchanger in the water-wet state The average diameter (μm) is calculated by the following formula: “average diameter (μm) of water holes in the monolith ion exchanger pores = z2 × (x2 / y2)”. In addition, the average diameter of the pores of the dried monolith before introduction of the ion exchange groups, and the swelling ratio of the water-dried monolith ion exchanger with respect to the dried monolith when the ion exchange groups are introduced into the dried monolith. If it is known, the average diameter of the monolith ion exchanger pores in the water-wet state can be calculated by multiplying the average diameter of the pores of the dry monolith by the swelling rate. Further, the average thickness of the skeleton of the continuous structure in the water-wet state is obtained by performing SEM observation of the dried monolith ion exchanger at least three times, and measuring the thickness of the skeleton in the obtained image. It is a value calculated by multiplying the average value by the swelling rate. Specifically, the water-wet monolith ion exchanger has a diameter of x3 (mm), the water-wet monolith ion exchanger is dried, and the resulting dried monolith ion exchanger has a diameter of y3 ( SEM observation of this dried monolith ion exchanger at least three times, the thickness of the skeleton in the obtained image was measured, and the average value was z3 (μm). The average thickness (μm) of the skeleton of the continuous structure of the ion exchanger in the water wet state is expressed by the following formula: “average thickness of the skeleton of the continuous structure of the monolith ion exchanger (μm) = z3 × (X3 / y3) ". In addition, the average thickness of the skeleton of the dried monolith before the introduction of the ion exchange group, and the swelling ratio of the monolith ion exchanger in the water wet state relative to the dried monolith when the ion exchange group is introduced into the dried monolith. When it is understood, the average thickness of the skeleton of the monolith ion exchanger can be calculated by multiplying the average thickness of the skeleton of the monolith in the dry state by the swelling ratio. The skeleton has a rod-like shape and a circular cross-sectional shape, but may have a cross-section with a different diameter such as an elliptical cross-sectional shape. The thickness in this case is the average of the minor axis and the major axis.

  If the thickness of the three-dimensional continuous rod-like skeleton is less than 10 μm, the second monolith ion exchanger is not preferable because the ion exchange capacity per volume is lowered, and if it exceeds 100 μm, the ion exchange characteristics This is not preferable because the uniformity of the film is lost. The definition and measurement method of the wall of the monolith ion exchanger are the same as those of the monolith.

  The second monolith ion exchanger has a total pore volume of 0.5 to 5 ml / g. When the total pore volume is less than 0.5 ml / g, the pressure loss of the concentrated water flowing through the monolith ion exchanger increases, and it becomes difficult to drain the carbon dioxide gas generated in the monolith ion exchanger together with the concentrated water. There is a case. On the other hand, if the total pore volume exceeds 5 ml / g, the strength of the monolith ion exchanger is decreased, and the electrical resistance of the electric deionized water production apparatus is increased. The total pore volume of the monolith (monolith intermediate, monolith, monolith ion exchanger) is the same in the dry state and in the water wet state.

  The pressure loss when water was permeated through the second monolith ion exchanger was the pressure loss when water was passed through a column filled with 1 m of a porous material at a water flow rate (LV) of 1 m / h (hereinafter referred to as “pressure loss”). And “differential pressure coefficient”) in the range of 0.001 to 0.5 MPa / m · LV, particularly 0.001 to 0.1 MPa / m · LV.

  In the second monolith ion exchanger, the material constituting the skeleton of the co-continuous structure is 0.3 to 5 mol%, preferably 0.5 to 3.0 mol% of the crosslinked structural unit in all the structural units. It is an aromatic vinyl polymer containing and is hydrophobic. If the cross-linking structural unit is less than 0.3 mol%, the mechanical strength is insufficient, which is not preferable. On the other hand, if it exceeds 5 mol%, the structure of the porous body tends to deviate from the bicontinuous structure. There is no restriction | limiting in particular in the kind of this aromatic vinyl polymer, For example, a polystyrene, poly ((alpha) -methylstyrene), polyvinyl toluene, polyvinyl benzyl chloride, polyvinyl biphenyl, polyvinyl naphthalene etc. are mentioned. The polymer may be a polymer obtained by copolymerizing a single vinyl monomer and a crosslinking agent, a polymer obtained by polymerizing a plurality of vinyl monomers and a crosslinking agent, or a blend of two or more types of polymers. It may be what was done. Among these organic polymer materials, a styrene-divinylbenzene copolymer is used because of its ease of forming a co-continuous structure, ease of introduction of ion exchange groups, high mechanical strength, and high stability against acids and alkalis. And vinylbenzyl chloride-divinylbenzene copolymer is preferred.

  The second monolith ion exchanger has an ion exchange capacity of 0.3 to 5 mg equivalent / ml cation exchange capacity per volume in a wet state of water. In the conventional monolithic organic porous ion exchanger having a continuous macropore structure different from the present invention as described in JP-A-2002-306976, in order to achieve a low pressure loss that is practically required, When the opening diameter is increased, the total pore volume also increases accordingly, so the strength of the monolith ion exchanger decreases, and the total pore volume is decreased in order to increase the exchange capacity per volume. In addition, since the opening diameter is reduced, the pressure loss increases. On the other hand, since the monolith ion exchanger of the present invention has high continuity and uniformity of three-dimensionally continuous pores, the pressure loss does not increase so much even if the total pore volume is reduced. The ion exchange capacity per weight in the dry state of the second monolith ion exchanger is not particularly limited, but the ion exchange groups are uniformly introduced to the skeleton surface and the skeleton inside the porous body. 5 mg equivalent / g. The ion exchange capacity of a porous body in which ion exchange groups are introduced only on the surface of the skeleton cannot be determined unconditionally depending on the kind of the porous body or ion exchange groups, but is at most 500 μg equivalent / g.

  The cation exchange group in the second monolith ion exchanger is the same as the ion exchange group in the first monolith ion exchanger, and the description thereof is omitted. In the second monolith ion exchanger, the introduced cation exchange groups are uniformly distributed not only on the surface of the porous body but also inside the skeleton of the porous body. The definition of the uniform distribution is the same as the definition of the uniform distribution of the first monolith ion exchanger.

(Method for producing second monolith ion exchanger)
The second monolith ion exchanger prepares a water-in-oil emulsion by stirring a mixture of oil-soluble monomer, surfactant and water that does not contain ion-exchange groups, and then polymerizes the water-in-oil emulsion. Step I for obtaining a monolithic organic porous intermediate having a continuous macropore structure having a total pore volume of more than 16 ml / g and 30 ml / g or less, an aromatic vinyl monomer, and at least two or more vinyl groups in one molecule From an organic solvent and a polymerization initiator in which 0.3 to 5 mol% of the cross-linking agent, aromatic vinyl monomer and cross-linking agent dissolve but the polymer formed by polymerization of the aromatic vinyl monomer does not dissolve in the total oil-soluble monomer having Step II for preparing the mixture, the mixture obtained in Step II is allowed to stand, and polymerization is performed in the presence of the monolithic organic porous intermediate obtained in Step I. III to obtain a continuous structure, obtained by performing the IV step of introducing ion exchange groups to resulting co-continuous structure in the step III.

  What is necessary is just to perform the I process of obtaining the monolith intermediate body in a 2nd monolith ion exchanger based on the method of Unexamined-Japanese-Patent No. 2002-306976.

  That is, in the step I, as the oil-soluble monomer not containing an ion exchange group, for example, it does not contain an ion exchange group such as a carboxylic acid group, a sulfonic acid group, and a quaternary ammonium group, has low solubility in water, and is lipophilic. These monomers are mentioned. Specific examples of these monomers include aromatic vinyl monomers such as styrene, α-methylstyrene, vinyl toluene, vinyl benzyl chloride, vinyl biphenyl and vinyl naphthalene; α-olefins such as ethylene, propylene, 1-butene and isobutene; butadiene Diene monomers such as vinyl chloride, vinyl bromide, vinylidene chloride and tetrafluoroethylene; nitrile monomers such as acrylonitrile and methacrylonitrile; vinyl esters such as vinyl acetate and vinyl propionate Methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethyl methacrylate Sill, cyclohexyl methacrylate, benzyl methacrylate, and (meth) acrylic monomer of glycidyl methacrylate. Among these monomers, preferred are aromatic vinyl monomers such as styrene, α-methylstyrene, vinyl toluene, vinyl benzyl chloride, divinyl benzene and the like. These monomers can be used alone or in combination of two or more. However, a crosslinkable monomer such as divinylbenzene or ethylene glycol dimethacrylate is selected as at least one component of the oil-soluble monomer, and its content is 0.3 to 5 mol%, preferably 0.3 to the total oil-soluble monomer. 3 mol% is preferable in that a mechanical strength necessary for introducing a large amount of ion-exchange groups in a later step can be obtained.

  The surfactant is the same as the surfactant used in step I of the first monolith ion exchanger, and the description thereof is omitted.

  In Step I, a polymerization initiator may be used as necessary when forming a water-in-oil emulsion. As the polymerization initiator, a compound that generates radicals by heat and light irradiation is preferably used. The polymerization initiator may be water-soluble or oil-soluble. For example, 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2 , 2′-azobis (2-methylbutyronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2′-azobisisobutyrate, 4,4′-azobis ( 4-cyanovaleric acid), 1,1'-azobis (cyclohexane-1-carbonitrile), benzoyl peroxide, lauroyl peroxide, potassium persulfate, ammonium persulfate, tetramethylthiuram disulfide, hydrogen peroxide-ferrous chloride Sodium persulfate-sodium acid sodium sulfite and the like.

  As a mixing method when an oil-soluble monomer not containing an ion exchange group, a surfactant, water and a polymerization initiator are mixed to form a water-in-oil emulsion, in the step I of the first monolith ion exchanger This is the same as the mixing method, and the description thereof is omitted.

  In the second method for producing a monolith ion exchanger, the monolith intermediate obtained in the step I is an organic polymer material having a crosslinked structure, preferably an aromatic vinyl polymer. Although the crosslinking density of the polymer material is not particularly limited, it contains 0.3 to 5 mol%, preferably 0.3 to 3 mol% of crosslinked structural units with respect to all structural units constituting the polymer material. Is preferred. When the cross-linking structural unit is less than 0.3 mol%, the mechanical strength is insufficient, which is not preferable. On the other hand, if it exceeds 5 mol%, the structure of the monolith tends to deviate from the co-continuous structure, which is not preferable. In particular, when the total pore volume is as small as 16 to 20 ml / g in the present invention, the cross-linking structural unit is preferably less than 3 mol in order to form a co-continuous structure.

  The type of the polymer material of the monolith intermediate is the same as the type of the polymer material of the monolith intermediate of the first monolith ion exchanger, and the description thereof is omitted.

  The total pore volume of the monolith intermediate is more than 16 ml / g and not more than 30 ml / g, preferably 6-25 ml / g. In other words, this monolith intermediate is basically a continuous macropore structure, but the opening (mesopore) that is the overlap between macropores and macropores is remarkably large. It has a structure as close as possible to the original rod-like skeleton. When this coexists in the polymerization system, a porous body having a co-continuous structure is formed using the structure of the monolith intermediate as a template. If the total pore volume is too small, the structure of the monolith obtained after polymerizing the vinyl monomer is not preferable because it changes from a co-continuous structure to a continuous macropore structure. On the other hand, if the total pore volume is too large, This is not preferable because the mechanical strength of the monolith obtained after polymerizing the vinyl monomer is lowered and the ion exchange capacity per volume is lowered. In order to make the total pore volume of the monolith intermediate within a specific range of the second monolith ion exchanger, the ratio of monomer to water may be approximately 1:20 to 1:40.

  Moreover, the average diameter of the opening (mesopore) which is an overlap part of a macropore and a macropore is a monolith intermediate body is 5-100 micrometers in a dry state. If the average diameter of the openings is less than 5 μm, the opening diameter of the monolith obtained after polymerizing the vinyl monomer becomes small, and the pressure loss during fluid permeation increases, which is not preferable. On the other hand, if it exceeds 100 μm, the opening diameter of the monolith obtained after polymerizing the vinyl monomer becomes too large, and the strength of the monorus may be lowered or the filling rate may be lowered, which is not preferable. Monolith intermediates preferably have a uniform structure with uniform macropore size and aperture diameter, but are not limited to this, and the uniform structure is dotted with nonuniform macropores larger than the size of the uniform macropore. You may do.

  In the second method for producing a monolithic ion exchanger, the step II includes 0.3 to 5 mol% of a crosslinking agent in the aromatic vinyl monomer and the total oil-soluble monomer having at least two or more vinyl groups in one molecule. This is a step of preparing a mixture comprising an organic solvent and a polymerization initiator that dissolves the aromatic vinyl monomer and the crosslinking agent but does not dissolve the polymer formed by polymerization of the aromatic vinyl monomer. In addition, there is no order of I process and II process, II process may be performed after I process, and I process may be performed after II process.

  In the second method for producing a monolithic ion exchanger, the aromatic vinyl monomer used in step II includes a lipophilic aromatic vinyl monomer that contains a polymerizable vinyl group in the molecule and has high solubility in an organic solvent. If it is, there is no particular limitation, but it is preferable to select a vinyl monomer that produces the same or similar polymer material as the monolith intermediate coexisting in the polymerization system. Specific examples of these vinyl monomers include styrene, α-methylstyrene, vinyl toluene, vinyl benzyl chloride, vinyl biphenyl, vinyl naphthalene and the like. These monomers can be used alone or in combination of two or more. Aromatic vinyl monomers preferably used in the present invention are styrene, vinyl benzyl chloride and the like.

  The amount of these aromatic vinyl monomers added is 5 to 50 times, preferably 5 to 40 times, by weight with respect to the monolith intermediate coexisting during polymerization. If the amount of the aromatic vinyl monomer added is less than 5 times that of the porous body, the rod-like skeleton cannot be made thick, and the ion exchange capacity per volume after the introduction of ion exchange groups becomes small.

  As the crosslinking agent used in step II, a crosslinking agent containing at least two polymerizable vinyl groups in the molecule and having high solubility in an organic solvent is preferably used. Specific examples of the crosslinking agent include divinylbenzene, divinylnaphthalene, divinylbiphenyl, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, butanediol diacrylate, and the like. These crosslinking agents can be used singly or in combination of two or more. Preferred cross-linking agents are aromatic polyvinyl compounds such as divinylbenzene, divinylnaphthalene and divinylbiphenyl because of their high mechanical strength and stability to hydrolysis. The amount of the crosslinking agent used is 0.3 to 5 mol%, particularly 0.3 to 3 mol%, based on the total amount of vinyl monomer and crosslinking agent (total oil-soluble monomer). When the amount of the crosslinking agent used is less than 0.3 mol%, it is not preferable because the mechanical strength of the monolith is insufficient. On the other hand, when the amount is too large, the brittleness of the monolith proceeds and the flexibility is lost. This is not preferable because a problem arises in that the amount of introduction of is reduced. In addition, it is preferable to use the said crosslinking agent usage-amount so that it may become substantially equal to the crosslinking density of the monolith intermediate body coexisted at the time of vinyl monomer / crosslinking agent polymerization. If the amounts used of both are too large, the crosslink density distribution is biased in the produced monolith, and cracks are likely to occur during the ion exchange group introduction reaction.

  The organic solvent used in step II is an organic solvent that dissolves the aromatic vinyl monomer and the crosslinking agent but does not dissolve the polymer formed by polymerization of the aromatic vinyl monomer, in other words, is formed by polymerization of the aromatic vinyl monomer. It is a poor solvent for polymers. Since the organic solvent varies greatly depending on the type of the aromatic vinyl monomer, it is difficult to list general specific examples. For example, when the aromatic vinyl monomer is styrene, the organic solvent includes methanol, ethanol, Alcohols such as propanol, butanol, hexanol, cyclohexanol, octanol, 2-ethylhexanol, decanol, dodecanol, propylene glycol, tetramethylene glycol; chain structures such as diethyl ether, butyl cellosolve, polyethylene glycol, polypropylene glycol, polytetramethylene glycol (Poly) ethers; chain saturated hydrocarbons such as hexane, heptane, octane, isooctane, decane, dodecane; ethyl acetate, isopropyl acetate, cellosolve acetate, propionic acid Examples include esters such as ethyl. Moreover, even if it is a good solvent of polystyrene like a dioxane, THF, and toluene, when it is used with the said poor solvent and the usage-amount is small, it can be used as an organic solvent. These organic solvents are preferably used so that the concentration of the aromatic vinyl monomer is 30 to 80% by weight. If the amount of the organic solvent used deviates from the above range and the aromatic vinyl monomer concentration becomes less than 30% by weight, the polymerization rate is lowered, or the monolith structure after polymerization deviates from the scope of the present invention, which is not preferable. On the other hand, if the concentration of the aromatic vinyl monomer exceeds 80% by weight, the polymerization may run away, which is not preferable.

  The polymerization initiator is the same as the polymerization initiator used in Step II of the first monolith ion exchanger, and the description thereof is omitted.

  In the second method for producing a monolith ion exchanger, in the step III, the mixture obtained in the step II is allowed to stand, and polymerization is performed in the presence of the monolith intermediate obtained in the step I. This is a process of changing the continuous macropore structure of the body to a co-continuous structure to obtain a monolith with a bone skeleton. The monolith intermediate used in the step III plays a very important role in creating the monolith having the novel structure of the present invention. As disclosed in JP-A-7-501140 and the like, when a vinyl monomer and a crosslinking agent are allowed to stand in a specific organic solvent in the absence of a monolith intermediate, a particle aggregation type monolithic organic porous material is obtained. The body is obtained. On the other hand, when a monolith intermediate having a specific continuous macropore structure is present in the polymerization system as in the second monolith of the present invention, the structure of the monolith after the polymerization changes dramatically and the particle aggregation structure disappears. Thus, a monolith having the above-described bicontinuous structure can be obtained. The reason for this has not been elucidated in detail, but in the absence of a monolith intermediate, the cross-linked polymer produced by polymerization precipitates and precipitates in the form of particles, while a particle aggregate structure is formed. When a porous body (intermediate) having a large total pore volume is present in the system, the vinyl monomer and the crosslinking agent are adsorbed or distributed from the liquid phase to the skeleton of the porous body, and polymerization proceeds in the porous body. It is considered that the skeleton constituting the monolith structure is changed from a two-dimensional wall surface to a one-dimensional rod-like skeleton to form a monolithic organic porous body having a co-continuous structure.

  The internal volume of the reaction vessel is the same as the description of the internal volume of the reaction vessel of the first monolith ion exchanger, and the description thereof is omitted.

  In step III, the monolith intermediate is placed in a reaction vessel impregnated with the mixture (solution). As described above, the blending ratio of the mixture obtained in Step II and the monolith intermediate is 5 to 50 times, preferably 5 to 40 times the weight of the aromatic vinyl monomer added to the monolith intermediate. It is preferable to blend them as described above. Thereby, it is possible to obtain a monolith having a co-continuous structure in which pores of an appropriate size are three-dimensionally continuous and a thick skeleton is three-dimensionally continuous. In the reaction vessel, the aromatic vinyl monomer and the cross-linking agent in the mixture are adsorbed and distributed on the skeleton of the monolith intermediate that is allowed to stand, and polymerization proceeds in the skeleton of the monolith intermediate.

  The basic structure of a monolith having a co-continuous structure is a three-dimensional continuous skeleton having an average thickness of 0.8 to 40 μm in a dry state and a three-dimensional continuous sky having a diameter of 8 to 80 μm between the skeletons. This is a structure in which holes are arranged. The average diameter of the three-dimensionally continuous pores can be obtained as a maximum value of the pore distribution curve by measuring the pore distribution curve by the mercury intrusion method. The thickness of the skeleton of the monolith may be calculated by performing SEM observation at least three times and measuring the average thickness of the skeleton in the obtained image. A monolith having a co-continuous structure has a total pore volume of 0.5 to 5 ml / g.

  The polymerization conditions are the same as the description of the polymerization conditions in step III of the first monolith ion exchanger, and the description thereof is omitted.

  In the step IV, the method for introducing an ion exchange group into a monolith having a co-continuous structure is the same as the method for introducing an ion exchange group into a monolith in the first monolith ion exchanger, and the description thereof is omitted.

  Since the ion exchange group is introduced into the bilithic monolith, the second monolith ion exchanger swells greatly, for example, 1.4 to 1.9 times that of the monolith. Further, the total pore volume does not change even if the pore diameter becomes larger due to swelling. Therefore, the second monolith ion exchanger has a high mechanical strength because it has a thick bone skeleton even though the size of three-dimensionally continuous pores is remarkably large. Moreover, since the skeleton is thick, the ion exchange capacity per volume in a wet state can be increased.

  In the said electrical deionized water manufacturing apparatus, the structure which makes the to-be-processed water contact from the anion exchanger 20 with which the 1st small demineralization chamber d1, d3, d5 was filled is illustrated. In the present embodiment, the water flow order of the ion exchanger filled in the desalting chamber and the ion exchanger filled in the desalting chamber are not particularly limited, but the first small desalting is described below. An electric deionized water production apparatus will be described in which the chamber is filled with a cation exchanger, the second small desalting chamber is filled with an anion exchanger, and the water to be treated is contacted in the order of the cation exchanger to the anion exchanger.

FIG. 15 is a schematic configuration diagram of an electric deionized water production apparatus according to another embodiment of the present invention. The first small desalting chambers d1, d3, and d5 shown in FIG. 15 are partitioned by the cation exchange membrane 10 and the intermediate ion exchange membrane 12, and the second small desalting chambers d2, d4, and d6 are defined by the intermediate ion exchange membrane 12. And an anion exchange membrane 14. Further, the first small desalting chambers d1, d3, d5 shown in FIG. 15 are filled with a cation exchanger 46, and the second small desalting chambers d2, d4, d6 are filled with an anion exchanger 20. Yes. In the present embodiment, the intermediate ion exchange membrane 12 is an anion exchange membrane, but is not limited to an anion exchange membrane. Moreover, since the concentration chambers 16a and 16b and the electrode chambers 28 and 30 have the same configuration as that of the electric deionized water production apparatus 1 in FIG.

  In the electric deionized water production apparatus 2 of FIG. 15, first inflow lines 36 through which water to be treated flows are connected to the inlets of the first small demineralization chambers d1, d3, d5, respectively. A first outflow line 38 for flowing out the water to be treated from the outlets of the salt chambers d1, d3, d5 is a second for flowing the water to be treated into the inlets of the second small desalting chambers d2, d4, d6. It is connected to the inflow line 40. A second outflow line 42 through which the treated water flows out is connected to the outlets of the second small desalting chambers d2, d4, and d6, respectively. With the above configuration, the water to be treated is first supplied to the first small desalting chambers d1, d3, and d5 and desalted. And the to-be-processed water which passed 1st small desalination chamber d1, d3, d5 is supplied to 2nd small desalination chamber d2, d4, d6, is further desalted, and is discharged | emitted as treated water. Moreover, since the structure of the concentrated water inflow line 48, the concentrated water outflow line 50, etc. is the same structure as the electric deionized water manufacturing apparatus 1 of FIG. 13, description is abbreviate | omitted.

  An example of an operation method in the case of producing deionized water by the electric deionized water production apparatus 2 according to this embodiment will be described below. First, in a state where a direct current is passed between the cathode 24 and the anode 26, water to be treated is introduced from the first inflow line 36 and concentrated water is introduced from the concentrated water inflow line 48. The treated water that has flowed in from the first inflow line 36 flows through the first small desalting chambers d1, d3, and d5, and the cations are removed when passing through the packed bed of the cation exchanger 46. Further, the treated water that has passed through the first outflow line 38 of the first small desalination chambers d1, d3, d5 passes through the second inflow line 40 of the second small desalination chambers d2, d4, d6, When flowing through the small desalting chambers d2, d4, d6 and passing through the packed bed of the anion exchanger 20, anions such as carbonic acid (free carbonic acid, bicarbonate ion, carbonate ion) and silica are removed, and treated water (deionized) Water) is obtained from the second outlet line 42. Further, the concentrated water flowing in from the concentrated water inflow line 48 flows through the concentration chambers 16a and 16b, receives ions moving through the cation exchange membrane 10 and the anion exchange membrane 14, and is used as concentrated water obtained by concentrating the ions. It flows out from the concentrated water outflow line 50. Furthermore, the electrode water flowing in from the concentrated water inflow line 48 (electrode water inflow line) flows out from the concentrated water outflow line 50 (electrode water outflow line).

  Carbonic acid (free carbonic acid, bicarbonate ion, carbonate ion) captured by the anion exchanger 20 in the second small desalting chambers d2, d4, d6 is other ions captured by the hydroxide ion or the anion exchanger 20. It passes through the anion exchange membrane 14 on the anode side together with the anion component, and moves to the concentration chambers 16a and 16b. In the present embodiment, since the monolithic organic porous cation exchanger 23 is disposed between the anion exchanger 22 and the cation exchange membrane 10 in the concentration chambers 16a and 16b, as described above, the high-concentration carbonic acid is used. The gas-containing aqueous solution layer is generated on or inside the monolithic organic porous cation exchanger 23 in contact with the anion exchanger 22, and the carbon dioxide gas flows out of the concentration chambers 16 a and 16 b together with the concentrated water before contacting the cation exchange membrane 10. Is done. Even if the carbon dioxide gas reaches the cation exchange membrane 10, the amount of carbon dioxide permeating the cation exchange membrane 10 is reduced because it is diluted (lowered in concentration) in the monolithic organic porous cation exchanger 23. It is greatly reduced. Therefore, it is possible to suppress the carbon dioxide gas from moving through the cation exchange membrane 10 to the first small desalting chambers d3 and d5 and backdiffusing into the water to be treated.

  In the present embodiment, the thickness of the first small desalting chambers d1, d3, d5 or the second small desalting chambers d2, d4, d6 is not particularly limited, but the first small desalting chambers d1, d3, d5 are not limited. If the thickness is 0.8 to 600 mm, preferably 2 to 100 mm, and the thickness of the second small desalting chambers d2, d4 and d6 is 0.8 to 600 mm, preferably 6 to 100 mm, low electrical resistance and This is preferable in that high current efficiency can be obtained. If the thickness of the first small desalting chambers d1, d3, d5 is less than 0.8 mm, sufficient residence time cannot be secured, and the water quality tends to deteriorate. On the other hand, if it exceeds 600 mm, the electric resistance is too large, and the stable operation of the apparatus tends to be hindered. Similarly, if the thickness of the second small desalting chambers d2, d4, d6 is less than 0.8 mm, sufficient residence time cannot be secured, and the water quality tends to deteriorate. On the other hand, if it exceeds 600 mm, the increase in electrical resistance tends to be more significant than the increase in current efficiency.

  The ion exchanger used as the anion exchanger (20, 32) and cation exchanger (34, 46) may be any substance as long as it has an ion exchange function, such as an ion exchange resin and an ion exchange fiber. May be combined.

  Examples of the anion exchanger 22 filled in the concentration chambers 16a and 16b include strong basic anion exchangers. Examples of the anion exchanger include anion exchange resins, anion exchange fibers, and organic porous anion exchangers described in JP-A No. 2002-306976. The strong basic anion exchanger may partially contain a weak basic anion exchange group. The anion exchange resin has an advantage that the reaction is sufficiently performed even when the free carbonic acid concentration is low, and scale generation can be suppressed. Moreover, it is preferable that the particle size of the anion exchange resin is uniform in that the differential pressure in the concentration chamber is reduced.

  Although it does not restrict | limit especially as thickness of the concentration chambers 16a and 16b, 0.5 mm-60 mm are preferable, and 1 mm-10 mm are especially preferable. If it is less than 0.5 mm, even if the anion exchanger 22 is filled, it becomes difficult to obtain an effect of suppressing the occurrence of scale, and the water flow differential pressure tends to increase. On the other hand, if it exceeds 60 mm, the electrical resistance increases and the power consumption tends to increase.

  In the electric deionized water production apparatus, the treatment amount (SV, LV), the energization amount, and other operating conditions can be appropriately set according to the properties of the water to be treated.

In the present embodiment, there is no particular restriction on the water to be treated, but even water to be treated that contains a large amount of carbonic acid components can prevent carbonation of the final treated water. Examples of water to be treated containing a large amount of carbonic acid component include tap water or water obtained by treating tap water with an RO membrane or the like. Domestic tap water usually contains a hardness component in addition to a carbonic acid component, but according to the present embodiment, the concentration chambers 16a and 16b are filled with the anion exchanger 22, and thus moved to the concentration chambers 16a and 16b. Ca ²⁺ ions and Mg ²⁺ ions are hardly combined with carbonate ions (CO ₃ ²⁻ ) on the surface of the anion exchange membrane 14 in the concentration chambers 16a and 16b to produce a hardness scale, and the channels are blocked in the concentration chambers 16a and 16b. There is almost no such thing.

(Example)
Next, the present invention will be specifically described by way of examples, but this is merely an example and does not limit the present invention.

<Production of first monolithic ion exchanger (Reference Example 1)>
(Step I; production of monolith intermediate)
19.2 g of styrene, 1.0 g of divinylbenzene, 1.0 g of sorbitan monooleate (hereinafter abbreviated as SMO) and 0.26 g of 2,2′-azobis (isobutyronitrile) were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / SMO / 2,2′-azobis (isobutyronitrile) mixture is added to 180 g of pure water containing 1.8 ml of THF, and a vacuum stirring defoaming mixer which is a planetary stirring device. (EM Co., Ltd.) was used and stirred under reduced pressure in a temperature range of 5 to 20 ° C. to obtain a water-in-oil emulsion. The emulsion was immediately transferred to a reaction vessel, and after sealing, it was allowed to polymerize at 60 ° C. for 24 hours. After completion of the polymerization, the content was taken out, extracted with isopropanol, and then dried under reduced pressure to produce a monolith intermediate having a continuous macropore structure. The average diameter of the openings (mesopores) where the macropores and macropores of the monolith intermediate were measured by mercury porosimetry was 56 μm, and the total pore volume was 7.5 ml / g.

(Manufacture of monoliths)
Next, 49.0 g of styrene, 1.0 g of divinylbenzene, 50 g of 1-decanol, and 0.5 g of 2,2′-azobis (2,4-dimethylvaleronitrile) were mixed and dissolved uniformly (step II). Next, the monolith intermediate was cut into a disk shape having an outer diameter of 70 mm and a thickness of about 20 mm, and 7.6 g was collected. The separated monolith intermediate is placed in a reaction vessel having an inner diameter of 90 mm, immersed in the styrene / divinylbenzene / 1-decanol / 2,2′-azobis (2,4-dimethylvaleronitrile) mixture, and removed in a vacuum chamber. After bubbling, the reaction vessel was sealed and allowed to polymerize at 60 ° C. for 24 hours. After completion of the polymerization, the monolith-like contents having a thickness of about 30 mm were taken out, subjected to Soxhlet extraction with acetone, and then dried under reduced pressure at 85 ° C. overnight (step III).

  FIG. 1 shows the result of observing the internal structure of the monolith (dry body) containing 1.3 mol% of the crosslinking component composed of the styrene / divinylbenzene copolymer obtained by SEM as described above. The SEM image in FIG. 1 is an image at an arbitrary position on a cut surface obtained by cutting a monolith at an arbitrary position. As is apparent from FIG. 1, the monolith has a continuous macropore structure, and the skeleton constituting the continuous macropore structure is much thicker than that of the conventional monolith shown in FIG. 12, and constitutes the skeleton. The wall was thick.

  Next, the thickness of the wall part and the area of the skeleton part appearing in the cross section were measured from two SEM images obtained by cutting the obtained monolith at a position different from the above position, excluding the subjectivity, and three convenient points. The wall thickness was an average of 8 points obtained from one SEM photograph, and the skeleton area was determined by image analysis. The wall portion has the above definition. Moreover, the skeleton part area was shown by the average of three SEM images. As a result, the average thickness of the wall portion was 30 μm, and the area of the skeleton portion represented by the cross section was 28% in the SEM image. Moreover, the average diameter of the opening of the monolith measured by mercury porosimetry was 31 μm, and the total pore volume was 2.2 ml / g. The results are summarized in Tables 1 and 2. In Table 1, the preparation column shows, in order from the left, the vinyl monomer used in Step II, the crosslinking agent, the monolith intermediate obtained in Step I, and the organic solvent used in Step II.

(Production of monolith cation exchanger)
The monolith produced by the above method was cut into a disk shape having an outer diameter of 70 mm and a thickness of about 15 mm. The weight of the monolith was 27 g. To this, 1500 ml of dichloromethane was added and heated at 35 ° C. for 1 hour, then cooled to 10 ° C. or lower, 145 g of chlorosulfuric acid was gradually added, and the temperature was raised and reacted at 35 ° C. for 24 hours. Thereafter, methanol was added to quench the remaining chlorosulfuric acid, which was then washed with methanol to remove dichloromethane and further washed with pure water to obtain a monolith cation exchanger having a continuous macropore structure.

  The swelling rate before and after the reaction of the obtained cation exchanger was 1.7 times, and the ion exchange capacity per volume was 0.67 mg equivalent / ml in a water-wet state. The average diameter of the openings of the organic porous ion exchanger in the water wet state was estimated from the value of the organic porous body and the swelling ratio of the cation exchanger in the water wet state, and was 54 μm. The average thickness of the wall part constituting the skeleton was 50 μm, the skeleton part area was 28% in the photographic region of the SEM photograph, and the total pore volume was 2.2 ml / g. Moreover, the ion exchange zone length regarding the sodium ion of this monolith cation exchanger was 22 mm in LV = 20 m / h. The differential pressure coefficient, which is an index of pressure loss when water is permeated, was 0.016 MPa / m · LV. The results are summarized in Table 2.

  Next, in order to confirm the distribution state of the sulfonic acid group in the monolith cation exchanger, the distribution state of sulfur atoms was observed by EPMA. The results are shown in FIGS. FIG. 2 shows a distribution state of sulfur atoms on the surface of the cation exchanger, and FIG. 3 shows a distribution state of sulfur atoms in the cross-section (thickness) direction of the cation exchanger. 2 and 3, it can be seen that the sulfonic acid groups are uniformly introduced into the surface of the cation exchanger and inside the skeleton (cross-sectional direction).

<Production of first monolith ion exchanger (Reference Examples 2 to 11)>
(Manufacture of monoliths)
Table 1 shows the amount of styrene used, the type and amount of crosslinking agent, the type and amount of organic solvent, the porous structure of the monolith intermediate coexisting during styrene and divinylbenzene impregnation polymerization, the crosslinking density and the amount used. A monolith was produced in the same manner as in Reference Example 1 except for the change. The results are shown in Tables 1 and 2. In addition, from the SEM images (not shown) of Reference Examples 2 to 11 and Table 2, the average diameter of the openings of the monoliths of Reference Examples 2 to 11 is as large as 22 to 70 μm, and the average thickness of the walls constituting the skeleton is also 25 to 25 mm. It was as thick as 50 μm, and the skeletal area was 26-44% in the SEM image area, and it was a monolith of bone.

(Production of monolith cation exchanger)
The monolith produced by the above method was reacted with chlorosulfuric acid in the same manner as in Reference Example 1 to produce a monolith cation exchanger having a continuous macropore structure. The results are shown in Table 2. The average diameters of the openings of the monolith cation exchangers of Reference Examples 2 to 11 are 46 to 138 μm, the average thickness of the wall portion constituting the skeleton is also as thick as 45 to 110 μm, and the skeleton area is 26 to 44% in the SEM image region. It is. The ion exchange zone length was shorter than the conventional one, and the differential pressure coefficient was also low. The exchange capacity per volume also showed a large value.

(Mechanical property evaluation of monolith cation exchanger)
The monolith cation exchanger obtained in Reference Example 8 was cut into a strip of 4 mm × 5 mm × 10 mm in a wet state, and used as a test piece for a tensile strength test. The test piece was attached to a tensile tester, the head speed was set to 0.5 mm / min, and the test was performed at 25 ° C. in water. As a result, the tensile strength and the tensile modulus were 45 kPa and 50 kPa, respectively, which were much larger than those of the conventional monolith cation exchanger. Further, the tensile elongation at break was 25%, which was a value larger than that of the conventional monolith cation exchanger.

<Production of Second Monolith Ion Exchanger (Reference Example 12)>
(Step I; production of monolith intermediate)
5.4 g of styrene, 0.17 g of divinylbenzene, 1.4 g of sorbitan monooleate (hereinafter abbreviated as SMO) and 0.26 g of 2,2′-azobis (isobutyronitrile) were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / SMO / 2,2′-azobis (isobutyronitrile) mixture was added to 180 g of pure water, and a vacuum stirring defoaming mixer (manufactured by EM Co.) as a planetary stirring device. Was used under reduced pressure in a temperature range of 5 to 20 ° C. to obtain a water-in-oil emulsion. This emulsion was quickly transferred to a reaction vessel and allowed to polymerize at 60 ° C. for 24 hours in a static state after sealing. After completion of the polymerization, the content was taken out, extracted with methanol, and then dried under reduced pressure to produce a monolith intermediate having a continuous macropore structure. When the internal structure of the monolith intermediate (dry body) obtained in this way was observed with an SEM image (FIG. 7), the wall portion separating two adjacent macropores was very thin and rod-shaped, but the open cell structure The average diameter of the openings (mesopores) where the macropores overlap with each other as measured by the mercury intrusion method was 70 μm, and the total pore volume was 21.0 ml / g.

(Manufacture of monocontinuous monolith)
Subsequently, 76.0 g of styrene, 4.0 g of divinylbenzene, 120 g of 1-decanol, and 0.8 g of 2,2′-azobis (2,4-dimethylvaleronitrile) were mixed and dissolved uniformly (step II). Next, the monolith intermediate was cut into a disk shape having a diameter of 70 mm and a thickness of about 40 mm to fractionate 4.1 g. The separated monolith intermediate is placed in a reaction vessel having an inner diameter of 75 mm, immersed in the styrene / divinylbenzene / 1-decanol / 2,2′-azobis (2,4-dimethylvaleronitrile) mixture, and removed in a vacuum chamber. After bubbling, the reaction vessel was sealed and allowed to polymerize at 60 ° C. for 24 hours. After completion of the polymerization, the monolithic contents having a thickness of about 60 mm were taken out, subjected to Soxhlet extraction with acetone, and then dried under reduced pressure at 85 ° C. overnight (step III).

  When the internal structure of the monolith (dry body) containing 3.2 mol% of the crosslinking component composed of the styrene / divinylbenzene copolymer obtained in this way was observed by SEM, the monolith had a skeleton and pores, respectively. It was a three-dimensional continuous structure with both phases intertwined. Moreover, the thickness of the skeleton measured from the SEM image was 10 μm. Further, the size of the three-dimensionally continuous pores of the monolith measured by mercury porosimetry was 17 μm, and the total pore volume was 2.9 ml / g. The results are summarized in Tables 3 and 4. In Table 4, the thickness of the skeleton was represented by the diameter of the skeleton.

(Production of co-continuous monolithic cation exchanger)
The monolith produced by the above method was cut into a disk shape having a diameter of 75 mm and a thickness of about 15 mm. The weight of the monolith was 18 g. To this was added 1500 ml of dichloromethane, heated at 35 ° C. for 1 hour, cooled to 10 ° C. or lower, gradually added 99 g of chlorosulfuric acid, heated up and reacted at 35 ° C. for 24 hours. Thereafter, methanol was added to quench the remaining chlorosulfuric acid, which was then washed with methanol to remove dichloromethane and further washed with pure water to obtain a monolith cation exchanger having a co-continuous structure.

  A part of the obtained cation exchanger was cut out and dried, and then its internal structure was observed by SEM. As a result, it was confirmed that the monolith cation body maintained a co-continuous structure. The SEM image is shown in FIG. Moreover, the swelling ratio before and after the reaction of the cation exchanger was 1.4 times, and the ion exchange capacity per volume was 0.74 mg equivalent / ml in a water-wet state. The size of the continuous pores of the monolith in the water wet state was estimated from the value of the monolith and the swelling ratio of the cation exchanger in the water wet state to be 24 μm, the skeleton diameter was 14 μm, and the total pore volume was 2. It was 9 ml / g.

  The differential pressure coefficient, which is an index of pressure loss when water is permeated, was 0.052 MPa / m · LV.

  Furthermore, when the ion exchange zone length for sodium ions of the monolith cation exchanger was measured, the ion exchange zone length at LV = 20 m / h was 16 mm, and Amberlite IR120B ( It was not only overwhelmingly shorter than the value (320 mm) manufactured by Rohm and Haas, but also shorter than the value of the monolithic porous cation exchanger having a conventional open cell structure. The results are summarized in Table 4.

  Next, in order to confirm the distribution state of the sulfonic acid group in the monolith cation exchanger, the distribution state of sulfur atoms was observed by EPMA. The results are shown in FIGS. 9 and 10, the left and right photographs correspond to each other. FIG. 9 shows a distribution state of sulfur atoms on the surface of the cation exchanger, and FIG. 10 shows a distribution state of sulfur atoms in the cross-section (thickness) direction of the cation exchanger. In the photograph on the left side of FIG. 9, a part extending in a horizontal direction is a skeleton part, and in the photograph on the left side of FIG. 10, two circular shapes are cross sections of the skeleton. 9 and 10, it can be seen that the sulfonic acid groups are uniformly introduced into the surface of the cation exchanger and inside the skeleton (cross-sectional direction).

<Production of Second Monolith Ion Exchanger (Reference Examples 13 to 15)>
(Manufacture of monolith with co-continuous structure)
Except for changing the amount of styrene used, the amount of crosslinking agent used, the amount of organic solvent used, the porous structure of the monolith intermediate coexisting during styrene and divinylbenzene impregnation polymerization, the crosslinking density and the amount used as shown in Table 3. A monolith having a co-continuous structure was produced in the same manner as in Reference Example 12. Reference Example 15 was carried out in the same manner as Reference Example 12 except that a reaction vessel having an inner diameter of 110 mm was used instead of the reaction vessel having an inner diameter of 75 mm. The results are shown in Tables 3 and 4.

(Manufacture of monolith with co-continuous structure)
The amount of styrene used, the amount of crosslinking agent used, the type and amount of organic solvent used, the porous structure of the monolith intermediate coexisting during styrene and divinylbenzene impregnation polymerization, the crosslinking density and the amount used were changed to the amounts shown in Table 4. Except for the above, a monolith having a co-continuous structure was produced in the same manner as in Reference Example 12. The results are shown in Tables 3 and 4.

(Production of monolith cation exchanger having a co-continuous structure)
The monolith produced by the above method was reacted with chlorosulfuric acid in the same manner as in Reference Example 12 to produce a monolith cation exchanger having a co-continuous structure. The results are shown in Table 4. Moreover, the internal structure of the obtained monolithic cation exchanger having a co-continuous structure is the same as that of the monolithic cation exchangers obtained in Reference Examples 13 to 15 from the SEM images and Table 4 (not shown). The differential pressure coefficient was lower than that of the above. Also, the ion exchange capacity per volume was larger than the conventional one.

(Mechanical property evaluation of monolith cation exchanger)
The monolith cation exchanger obtained in Reference Example 13 was cut into a strip of 4 mm × 5 mm × 10 mm in a wet state of water and used as a test piece for a tensile strength test. The test piece was attached to a tensile tester, the head speed was set to 0.5 mm / min, and the test was performed at 25 ° C. in water. As a result, the tensile strength and the tensile modulus were 23 kPa and 15 kPa, respectively, which were significantly larger than the conventional monolith cation exchanger. Further, the tensile elongation at break was 50%, which was a value larger than that of the conventional monolith cation exchanger.

Reference Example 16
(Manufacture of monolithic organic porous material (known product))
A monolithic organic porous body having a continuous macropore structure was produced according to the production method described in JP-A-2002-306976. That is, 19.2 g of styrene, 1.0 g of divinylbenzene, 1.0 g of SMO and 0.26 g of 2,2′-azobis (isobutyronitrile) were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / SMO / 2,2′-azobis (isobutyronitrile) mixture is added to 180 g of pure water, and a vacuum stirring defoaming mixer (manufactured by EM Corp.) which is a planetary stirring device. Was used under reduced pressure in a temperature range of 5 to 20 ° C. to obtain a water-in-oil emulsion. The emulsion was immediately transferred to a reaction vessel, and after sealing, it was allowed to polymerize at 60 ° C. for 24 hours. After completion of the polymerization, the content was taken out, extracted with isopropanol, and then dried under reduced pressure to produce a monolithic organic porous body having a continuous macropore structure.

  The SEM representing the internal structure of the organic porous material containing 3.3 mol% of the crosslinking component composed of the styrene / divinylbenzene copolymer thus obtained had the same structure as FIG. As is clear from FIG. 12, the organic porous body has a continuous macropore structure, but the thickness of the wall portion constituting the skeleton of the continuous macropore structure is thinner than that of the reference example. The measured wall thickness average thickness was 5 μm, and the skeleton area was 10% in the SEM image area. Moreover, the average diameter of the opening of the organic porous material measured by mercury porosimetry was 29 μm, and the total pore volume was 8.6 ml / g. The results are summarized in Table 5. In Tables 1, 2 and 5, the mesopore diameter means the average diameter of the openings. Moreover, in Tables 1-5, the value of thickness, skeleton diameter, and a void | hole each shows an average.

(Production of monolithic organic porous cation exchanger having a continuous macropore structure (known product))
The organic porous body produced by the above method was cut into a disk shape having an outer diameter of 70 mm and a thickness of about 15 mm. The weight of the organic porous material was 6 g. To this was added 1000 ml of dichloromethane, and the mixture was heated at 35 ° C. for 1 hour, then cooled to 10 ° C. or less, 30 g of chlorosulfuric acid was gradually added, and the temperature was raised and reacted at 35 ° C. for 24 hours. Thereafter, methanol was added to quench the remaining chlorosulfuric acid, which was washed with methanol to remove dichloromethane and further washed with pure water to obtain a monolithic porous cation exchanger having a continuous macropore structure. The swelling rate before and after the reaction of the obtained cation exchanger was 1.6 times, and the ion exchange capacity per volume was 0.22 mg equivalent / ml in a water-wet state, which was a small value compared to Reference Example 1 and the like. It was. The average diameter of the mesopores of the organic porous ion exchanger in the water wet state was 46 μm as estimated from the value of the organic porous body and the swelling ratio of the cation exchanger in the water wet state. The average thickness was 8 μm, the skeleton part area was 10% in the SEM image area, and the total pore volume was 8.6 ml / g. The differential pressure coefficient, which is an index of pressure loss when water is permeated, was 0.013 MPa / m · LV. The results are summarized in Table 5. The monolith cation exchanger obtained in Reference Example 16 was also evaluated for mechanical properties.

(Mechanical property evaluation of conventional monolith cation exchanger)
The monolith cation exchanger obtained in Reference Example 16 was subjected to a tensile test by the same method as the evaluation method of Reference Example 8. As a result, the tensile strength and the tensile modulus were 28 kPa and 12 kPa, respectively, which were lower than the monolith cation exchanger of Reference Example 8. The tensile elongation at break was 17%, which was smaller than that of the monolith cation exchanger of the present invention.

Reference Examples 17-19
(Manufacture of monolithic organic porous body having continuous macropore structure)
A monolithic organic porous material having a continuous macropore structure in the same manner as in Reference Example 16 except that the amount of styrene used, the amount of divinylbenzene, and the amount of SMO used are changed to the amounts shown in Table 5. The body was manufactured. The results are shown in Table 5. Further, the internal structure of the monolith of Reference Example 19 was observed with an SEM (not shown). Reference Example 19 is a condition for minimizing the total pore volume, and an opening cannot be formed when the water content is less than that of the oil phase portion. Each of the monoliths of Reference Examples 17 to 19 has an opening diameter as small as 9 to 18 μm, the average thickness of the wall part constituting the skeleton is as thin as 15 μm, and the skeleton part area is as small as 22% at the maximum in the SEM image region. It was.

(Production of monolithic organic porous cation exchanger having a continuous macropore structure)
The organic porous material produced by the above method was reacted with chlorosulfuric acid in the same manner as in Reference Example 12 to produce a monolithic porous cation exchanger having a continuous macropore structure. The results are shown in Table 5. If the opening diameter is increased, the thickness of the wall portion is reduced or the skeleton is reduced. On the other hand, when the wall portion was made thicker or the skeleton was made thicker, the diameter of the opening tended to decrease. As a result, when the differential pressure coefficient was kept low, the ion exchange capacity per volume decreased, and when the ion exchange capacity was increased, the differential pressure coefficient increased.

  In addition, about the monolith ion exchanger manufactured by Reference Examples 1-11 and Reference Examples 16-19, the relationship between a differential pressure coefficient and the ion exchange capacity per volume was shown in FIG. As is apparent from FIG. 4, it can be seen that the comparative example has a poor balance between the differential pressure coefficient and the ion exchange capacity with respect to the reference example. On the other hand, the reference example shows a large ion exchange capacity per volume and a low differential pressure coefficient.

FIG. 16 is a schematic configuration diagram showing a test cell for measuring the amount of carbonic acid components moving from the concentration chamber to the desalting chamber. As shown in FIG. 16, an anion exchange membrane 64 and a first cation exchange membrane 66 are partitioned between a cathode chamber 58 filled with an anion exchange resin 56 and an anode chamber 62 filled with a cation exchange resin 60. The concentration chamber 68, the first cation exchange membrane 66 and the first cation exchange membrane 66 in which the monolithic organic porous cation exchanger 54 is disposed between the anion exchange resin 56 and the first cation exchange membrane 66 are filled with the anion exchange resin 56. A test cell 3 having a demineralization chamber 72 filled with a cation exchange resin 60 in a chamber partitioned by a dication exchange membrane 70 is prepared, and a carbonic acid component that moves from the concentration chamber 68 to the demineralization chamber 72 under the following conditions The amount was measured. In Example 1, ultrapure water was passed through the desalting chamber 72 and the electrode chambers (58, 62), and a NaHCO ₃ solution (carbonate concentration 30 mg-CaCO ₃ / L) was passed through the concentration chamber 68. .

<Ion exchanger used>
Monolithic organic porous cation exchanger: Monolith ion exchanger of Reference Example 8 Cation exchange resin: Amberlite IRA402BL manufactured by Rohm and Haas
Anion exchange resin: Rohm and Haas, Amberlite IRA402BL
First cation exchange membrane, second cation exchange membrane: manufactured by Astom Co., Ltd., C66-10F
Anion exchange membrane: manufactured by Astom Co., Ltd., AHA
<EDI size>
Test cell: 10cm long x 10cm wide x 8mm thick
<Flow conditions>
Ultrapure water, NaHCO ₃ solution, CO ₂ -containing solution: 8000 ml / hr
<Current conditions>
Constant current: 0.5 A / dm ²

  The same procedure as in Example 1 was performed except that the monolith ion exchanger of Reference Example 15 was used instead of the monolith ion exchanger of Reference Example 8.

Instead of the solution of NaHCO _3, except for using the CO ₂ containing solution (carbonate ion concentration 30mg-CaCO ₃ / L) was performed under the same conditions as in Example 1.

Instead of the solution of NaHCO _3, except for using the CO ₂ containing solution (carbonate ion concentration 30mg-CaCO ₃ / L) was performed under the same conditions as in Example 2.

Comparative Example 1
Except that the anion exchange resin 56 in the concentrating compartment 68 is not disposed monolithic organic porous cation exchanger 54 between the first cation exchange membrane 66, it was carried out under the same conditions as in Example 1.

Comparative Example 2
Except that the anion exchange resin 56 in the concentrating compartment 68 is not disposed monolithic organic porous cation exchanger 54 between the first cation exchange membrane 66, it was carried out under the same conditions as in Example 2.

The amount of carbonic acid in the treated water (ultra pure water) discharged from the desalting chambers of Examples 1 to 4 and Comparative Examples 1 and 2 was measured. Specifically, inorganic carbon (IC) in the treated water was measured with a TOC meter (A-1000) manufactured by Altena, and the amount of carbonic acid in the treated water was measured using this as carbonic acid. The treated water discharged from the desalting chambers of Comparative Example 1 and Comparative Example 2 contained carbonic acid components of 8400 μg-CaCO ₃ / hr and 9000 μg-CaCO ₃ / hr. On the other hand, the treated water discharged from the desalting of Examples 1 to _{4, 270μg-CaCO 3 / hr} , 300μg-CaCO 3 / hr, 170μg-CaCO 3 / hr, the 190μg-CaCO ₃ / hr Although the carbonic acid component was contained, the amount of the carbonic acid component was significantly suppressed as compared with Comparative Example 1 and Comparative Example 2. That is, by disposing the monolithic organic porous cation exchanger between the anion exchange resin and the cation exchange membrane in the concentration chamber, the carbonic acid component in the concentration chamber moves to the desalination chamber through the cation exchange membrane. It was confirmed that it could be suppressed.

1, 2 Electric deionized water production apparatus, 3 test cell, 10, 66, 70 cation exchange membrane, 12 intermediate ion exchange membrane, 14, 64 anion exchange membrane, 16a, 16b, 68 concentration chamber, 18 mixture, 20 , 22, 32 Anion exchanger, 23 monolithic organic porous cation exchanger, 24 cathode, 25 frame, 26 anode, 28, 30, 58, 62 electrode chamber, 34, 46 cation exchanger, 36 first inflow line , 38 first outflow line, 40 second inflow line, 42 second outflow line 48 concentrated water inlet line, 50 concentrated water outlet line, 54 a monolith-shaped organic porous cation exchanger, 56 anion exchange resin 60 cation exchange resin 72, D1, D2, D3 desalting chamber, d1, d3, d5 first small desalting chamber, d2, d4, d6 second small desalting chamber, 81 rectangular photographic area 82 Skeleton 83 macropores 90 bicontinuous structure 91 skeletal phase 92 Soraanasho appearing

Claims (5)

Between the anode and the cathode, it is partitioned by a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side, and a desalting chamber filled with an ion exchanger, through the cation exchange membrane and the anion exchange membrane An electric deionized water production apparatus that is provided on both sides of the demineralization chamber and has a concentration chamber filled with an anion exchanger,
A monolithic organic porous cation exchanger is disposed between the anion exchanger in the concentration chamber and the cation exchange membrane,
The monolithic organic porous cation exchanger is a continuous macropore structure in which bubble-shaped macropores overlap each other, and the overlapping portion is an opening having an average diameter of 30 to 300 μm in a water-wet state, and has a total pore volume of 0.5. Electric deionization characterized in that, in the SEM image of the cut surface of the continuous macropore structure (dried body), the area of the skeleton part shown in the cross section is 25 to 50% in the image region. Water production equipment. Between the anode and the cathode, it is partitioned by a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side, and a desalting chamber filled with an ion exchanger, through the cation exchange membrane and the anion exchange membrane An electric deionized water production apparatus that is provided on both sides of the demineralization chamber and has a concentration chamber filled with an anion exchanger,
A monolithic organic porous cation exchanger is disposed between the anion exchanger in the concentration chamber and the cation exchange membrane,
The monolith organic porous cation exchanger, overlapping bubble-like macropores between, the overlapping portion is a continuous macropores structure an average diameter 30 ~ 300 [mu] m aperture with water wet state, the total pore volume 0. 5-5 ml / g, the following steps:
A water-in-oil emulsion is prepared by stirring a mixture of oil-soluble monomer, surfactant and water that does not contain ion exchange groups, and then the water-in-oil emulsion is polymerized to give a total pore volume of 5-16 ml / g, a monolithic organic porous intermediate having a continuous macropore structure,
A mixture comprising a vinyl monomer, a crosslinking agent having at least two vinyl groups in one molecule, an organic solvent that dissolves the vinyl monomer and the crosslinking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer, and a polymerization initiator. Step II to prepare,
The mixture obtained in Step II is allowed to stand and polymerized in the presence of the monolithic organic porous intermediate obtained in Step I, and the bone thicker having a skeleton thicker than the skeleton of the organic porous intermediate. Step III for obtaining an organic porous material,
An electric deionized water production apparatus obtained by performing an IV step of introducing a cation exchange group into the thick organic porous material obtained in the step III. A demineralization chamber partitioned between a cathode and a cation exchange membrane on the cathode side and an anion exchange membrane on the anode and filled with an ion exchanger, the cation exchange membrane, and the anion exchange membrane through the anion exchange membrane An electric deionized water production apparatus in which a concentration chamber provided on both sides of a demineralization chamber and filled with an anion exchanger is disposed,
A monolithic organic porous cation exchanger is disposed between the anion exchanger in the concentration chamber and the cation exchange membrane,
The monolithic organic porous cation exchanger has a thickness of 1 to 60 μm made of an aromatic vinyl polymer containing 0.3 to 5.0 mol% of a crosslinked structural unit among all the structural units into which ion exchange groups are introduced. A three-dimensionally continuous skeleton and a three-dimensionally continuous pore having a diameter of 10 to 100 μm between the skeletons, and the total pore volume is 0.5 to 5 ml / An apparatus for producing electrical deionized water, wherein g is g. Between the anode and the cathode, it is partitioned by a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side, and a desalting chamber filled with an ion exchanger, through the cation exchange membrane and the anion exchange membrane A deionized water production method for producing deionized water using an electric deionized water production apparatus that is provided on both sides of the demineralization chamber and is provided with a concentration chamber filled with an anion exchanger. , Between the anion exchanger in the concentration chamber and the cation exchange membrane, bubble-like macropores overlap each other, and this overlapping portion is a continuous macropore structure in which the overlapping portion is an opening having an average diameter of 30 to 300 μm in a water-wet state, Monolithic shape having a total pore volume of 0.5 to 5 ml / g, and having a skeleton part area of 25 to 50% in the image area in the SEM image of the cut surface of the continuous macropore structure (dried body) Yes Method for producing deionized water, which comprises placing a porous cation exchanger. Between the anode and the cathode, it is partitioned by a cation exchange membrane on the cathode side and an anion exchange membrane on the anode side, and a desalting chamber filled with an ion exchanger, through the cation exchange membrane and the anion exchange membrane A deionized water production method for producing deionized water using an electric deionized water production apparatus that is provided on both sides of the demineralization chamber and is provided with a concentration chamber filled with an anion exchanger. From an aromatic vinyl polymer containing 0.3 to 5.0 mol% of a crosslinked structural unit among all the structural units having an ion exchange group introduced between the anion exchanger in the concentration chamber and the cation exchange membrane. A co-continuous structure comprising a three-dimensionally continuous skeleton having a thickness of 1 to 60 μm and three-dimensionally continuous pores having a diameter of 10 to 100 μm between the skeletons, and having a total pore volume Monolithic organic with a 0.5 to 5 ml / g Method for producing deionized water, which comprises placing the porosifying cation exchanger.