JP5116724B2 - Ultrapure water production equipment - Google Patents

Description

  The present invention relates to an ultrapure water production apparatus used in the semiconductor manufacturing industry and the like, and more specifically, an ion adsorption module for further purifying ultrapure water immediately before the use point, The present invention relates to an ultrapure water production apparatus that can be stably supplied to the water.

  Ultrapure water (in the present specification, high-purity water that is generally not necessarily clearly defined and described in terms of pure water, ultrapure water, etc., is collectively referred to as “ultrapure water”). In general, treated water such as river water, groundwater and industrial water is treated in the pretreatment process to remove most of the suspended matter and organic matter in the treated water, and then this pretreated water is produced as primary pure water. It is manufactured by sequentially processing with an apparatus and a secondary pure water manufacturing apparatus (subsystem) and supplied to a use point for performing wafer cleaning in the semiconductor manufacturing industry, for example. Such ultrapure water has such a high purity that it is difficult to quantify impurities, but it does not contain impurities at all. The effects of ultra-trace components contained in ultra-pure water on products such as semiconductor devices cannot be ignored when the density of devices increases, and ultra-pure water with higher purity than conventional ultra-pure water is required. Sex is also being investigated.

  For example, ultrapure water produced by the subsystem is supplied to the point of use via a pipe, but the pipe between the subsystem and the point of use may be several hundred meters long. For this reason, impurities such as fine particles (particles) and metal ion components are slightly mixed into the ultrapure water from this pipe, which may adversely affect the characteristics of the device. For example, metal contamination may deteriorate the electrical characteristics of the device, and particles may cause pattern defects, disconnection, and breakdown voltage. Furthermore, when a component that cannot be completely removed by the ultrapure water production apparatus or a leak from the ultrapure water production apparatus for a certain reason or for a certain period of time, the device characteristics may be similarly adversely affected.

  As means for coping with such a situation, Japanese Patent Application Laid-Open No. 2003-266069 discloses an ultrapure water production apparatus that transports ultrapure water to a point of use and transfers the ultrapure water halfway through the pipe that transports the ultrapure water. And having an open cell structure with mesopores having an average diameter of 1 to 1,000 μm in the macropores and the walls of the macropores, the total pore volume being 1 ml / g to 50 ml / g, Is installed uniformly, and a module filled with an organic porous ion exchanger having a three-dimensional network structure having an ion exchange capacity of 0.5 mg equivalent / g or more of a dry porous body is installed, and ultrapure water is supplied with the module. An ultrapure water production apparatus for further processing is disclosed.

  According to the ultrapure water production apparatus disclosed in Japanese Patent Application Laid-Open No. 2003-266069, even if a very small amount of impurities such as fine particles (particles) and ionic components are slightly mixed in the ultrapure water being transferred, the fine particles and ionic components, etc. Both of them can be removed, and high-purity pure water suitable for manufacturing highly integrated devices can be stably obtained. Moreover, the replacement frequency of the module can be significantly reduced. JP-A-2002-306976 discloses details of the method for producing the organic porous ion exchanger.

JP 2003-266069 A (Claims) JP 2002-306976 A JP 2009-62512 A JP 2009-67982 A

  However, the organic porous ion exchanger used in the ultrapure water production apparatus disclosed in Japanese Patent Application Laid-Open No. 2003-266069 is described as having a common opening (mesopore) of monoliths of 1 to 1,000 μm. 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. For this reason, there existed a problem that water flow differential pressure | voltage will become large. In addition, when the average diameter of the openings is around 20 μm, the total pore volume also increases accordingly, so that the ion exchange capacity per volume decreases, the ion exchange zone length is long, and the module replacement frequency is high. There was a problem of becoming. In addition, a monolith with a new structure different from an open cell structure (continuous macropore) has been desired for a monolith loaded in an ion adsorption module for further purifying ultrapure water immediately before the use point.

  Therefore, the object of the present invention is to remove an ionic component even when a very small amount of impurities as an ionic component is mixed in ultrapure water transferred to a use point, and to achieve ultrapure water suitable for manufacturing highly integrated devices. Providing ultra-pure water production equipment that can supply water stably, further reduce the differential pressure of water flow, shorten the ion exchange zone length, and increase the ion exchange capacity per volume, thus reducing the frequency of module exchange. There is to do.

  Under such circumstances, the present inventors have conducted intensive studies, and as a result, the existence of a monolithic organic porous material (intermediate) having a relatively large pore volume obtained by the method described in JP-A-2002-306976. Below, if a vinyl monomer and a crosslinking agent are allowed to stand in a specific organic solvent under specific conditions, a large number of particles having a diameter of 2 to 20 μm are fixed on the surface of the skeleton constituting the organic porous material. A monolith having a composite structure with protrusions can be obtained, and a monolith ion exchanger in which an ion exchange group is introduced into the monolith with a composite structure is used to manufacture ultrapure water by transferring ultrapure water to a point of use by piping. In the equipment, if it is used as a module filler (adsorbent) in the middle of a pipe for transferring the ultrapure water, a very small amount of impurities, which are ionic components, is slightly mixed in the ultrapure water transferred to the use point. Even in this case, the ion component is removed, ultrapure water suitable for the production of highly integrated devices, etc. is stably supplied, the water flow differential pressure can be reduced, the ion exchange zone length can be shortened, and the volume per volume can be reduced. Since the ion exchange capacity is large, it has been found that the frequency of module exchange can be reduced, and the present invention has been completed.

That is, the present invention is an ultrapure water production apparatus for supplying ultrapure water to a point of use by transferring the ultrapure water.
An organic porous body composed of a continuous skeleton phase and a continuous pore phase, and a large number of particles having a diameter of 4 to 40 μm fixed to the skeleton surface of the organic porous body or the skeleton surface of the organic porous body A composite structure with a large number of protrusions having a size of 4 to 40 μm, having an average pore diameter of 10 to 150 μm in a water-wet state, a total pore volume of 0.5 to 5 ml / g, and being in a water-wet state A module filled with a monolithic organic porous ion exchanger obtained by the following method for producing a monolithic organic porous ion exchanger having an ion exchange capacity per volume of 0.2 mg equivalent / ml or more, and the module The present invention provides an ultrapure water production apparatus characterized by further processing ultrapure water.
Method for producing monolithic organic porous ion exchanger:
Preparing a water-in-oil emulsion by stirring a mixture of an oil-soluble monomer free of ion exchange groups, a first crosslinking agent having at least two or more vinyl groups in one molecule, a surfactant and water; Step I for polymerizing a water-in-oil emulsion to obtain a monolithic organic porous intermediate having a continuous macropore structure with a total pore volume of 5 to 30 ml / g, vinyl monomer, at least two vinyls in one molecule Obtained in Step II and Step II to prepare a mixture comprising an organic solvent and a polymerization initiator that dissolves the second cross-linking agent having a group, the vinyl monomer and the second cross-linking agent, but does not dissolve the polymer formed by polymerization of the vinyl monomer. The resulting mixture is allowed to stand still and in the presence of the monolithic organic porous intermediate obtained in the step I, the step III, the monolith obtained in the step III IV introducing ion exchange groups into Jo organic porous material, a method of manufacturing a monolithic organic porous material for performing the following (1) to (5):
(1) The polymerization temperature in step III is at least 5 ° C. lower than the 10-hour half-life temperature of the polymerization initiator;
(2) The mol% of the second cross-linking agent used in step II is at least twice the mol% of the first cross-linking agent used in step I;
(3) The vinyl monomer used in Step II is a vinyl monomer having a structure different from that of the oil-soluble monomer used in Step I;
(4) The organic solvent used in step II is a polyether having a molecular weight of 200 or more;
(5) The concentration of the vinyl monomer used in Step II is 30% by weight or less in the mixture of Step II;
A method for producing a monolithic organic porous ion exchanger, wherein the step II or the step III is performed under conditions satisfying at least one of the above conditions.

  According to the present invention, even if a very small amount of impurities, which are ionic components, is mixed in ultrapure water transferred to a use point, ultrapure water suitable for the manufacture of highly integrated devices is removed by removing ionic components. It is possible to supply stably, further reduce the water differential pressure, shorten the ion exchange zone length, and increase the ion exchange capacity per volume, thereby reducing the frequency of module replacement. According to the present invention, the above effect can be achieved only by installing the module in the middle of ultrapure water transfer piping of an ultrapure water production apparatus used in the semiconductor manufacturing industry or the like. According to the present invention, metals that have a particularly bad influence on semiconductor devices can be effectively removed.

4 is a SEM image of a monolith obtained in Reference Example 1 at a magnification of 100. FIG. 3 is a SEM image of a monolith obtained in Reference Example 1 at a magnification of 300. 3 is an SEM image of the monolith obtained in Reference Example 1 at a magnification of 3000. 2 is an EPMA image showing the distribution state of sulfur atoms on the surface of the monolith cation exchanger obtained in Reference Example 1. FIG. 2 is an EPMA image showing a distribution state of sulfur atoms in the cross-section (thickness) direction of the monolith cation exchanger obtained in Reference Example 1. FIG. 10 is a SEM image of a monolith obtained in Reference Example 2 at a magnification of 100. 6 is an SEM image of a monolith obtained in Reference Example 2 at a magnification of 600. 4 is an SEM image of the monolith obtained in Reference Example 2 at a magnification of 3000. 10 is an SEM image of a monolith obtained in Reference Example 3 at a magnification of 600. 10 is an SEM image of the monolith obtained in Reference Example 3 at a magnification of 3000. 10 is a SEM image of the monolith obtained in Reference Example 4 at a magnification of 3000. 10 is an SEM image of a monolith obtained in Reference Example 5 at a magnification of 100. 10 is a SEM image of the monolith obtained in Reference Example 5 at a magnification of 3000. 10 is a SEM image of a monolith obtained in Reference Example 6 at a magnification of 100. 10 is an SEM image of a monolith obtained in Reference Example 6 at a magnification of 600. 10 is an SEM image of the monolith obtained in Reference Example 6 at a magnification of 3000. It is a flowchart of the ultrapure water manufacturing apparatus in embodiment of this invention. It is a flowchart of the water flow test apparatus used by the Example and the comparative example. It is typical sectional drawing of a protrusion.

  An ultrapure water production apparatus according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 17, the ultrapure water production apparatus 10a includes a pretreatment apparatus 20, a primary pure water production apparatus 30, a secondary pure water production apparatus (subsystem) 50, and a secondary pure water production apparatus. 50 and the ion adsorption module 6 installed in the middle of the ultrapure water transfer pipe 3 connecting the use point 4. That is, the ion adsorption module 6 treats ultrapure water, and stably removes both a very small amount of fine particles and ion components contained in the ultrapure water over a long period of time. The pretreatment device 20 includes, for example, a coagulation filtration device 22 and an activated carbon tower 23. The primary pure water production device 30 includes, for example, a reverse osmosis membrane module 31 loaded with a reverse osmosis membrane and a two-bed / three-column pure water production. The secondary pure water production apparatus 50 includes, for example, an ultraviolet oxidation apparatus 51, a non-regenerative type cartridge polisher 52 filled with an ion exchange resin, and a limiter. It consists of an outer filtration membrane device 53. Reference numeral 34 denotes a primary pure water storage tank that stores the primary pure water and returns the remainder other than the consumed amount of ultrapure water supplied to the use point 4. In the present invention, the ultrapure water production apparatus for producing the ultrapure water 54 is not limited to the above exemplified apparatus, and has at least an ion exchange device, a reverse osmosis membrane device, a distillation device, etc. As long as it contains. Therefore, the ultrapure water in the present invention is one that has been processed by the pretreatment device, the primary pure water production device and the secondary pure water production device as described above, or has a resistivity of 10 MΩ- What is above cm is sufficient. If the purity of the water to be treated is too bad, the filled porous ion exchanger is saturated immediately and the exchange frequency of the ion adsorption module 6 is increased, which is not preferable.

  The ion adsorption module 6 used in this example connects the secondary pure water production apparatus 50 and the use point 4 among the pipes 5 that connect the secondary pure water production apparatus 50 and the primary pure water storage tank 34. Installed in the middle of the ultrapure water transfer pipe 3. The installation location of the ion adsorption module 6 is not particularly limited. However, it is preferable that the ion adsorption module 6 be installed in the immediate vicinity of the use point 4, particularly when the ultrapure water transfer pipe 3 has a length of several tens of meters or more. It is preferable in that it can cope with impurities mixed in the ultrapure water. When the pipe length between the secondary pure water production apparatus 50 and the ion adsorption module 6 is 10 m or longer, particularly 20 m or longer, and further 100 m or longer, the effect of the present invention is remarkably exhibited. Further, depending on the purpose of use of water at the point of use 4, a gas dissolving membrane device may be installed before or after the ion adsorption module 6 to dissolve gases such as ozone and hydrogen, or an ultrafiltration membrane device may be further provided at the latter stage. Etc. may be installed.

  The ion adsorption module 6 includes a container-like support structure having an inlet connected to the treated water inflow pipe and an outlet connected to the treated water outflow pipe, and a composite monolith ion exchange filled in the support structure. Consists of the body.

  In this specification, “monolithic organic porous body” is simply “composite monolith”, “monolithic organic porous ion exchanger” is simply “composite monolithic ion exchanger”, and “monolithic organic porous intermediate”. "Body" is also simply called "monolith intermediate".

<Description of composite monolith ion exchanger>
A composite monolith ion exchanger is obtained by introducing an ion exchange group into a composite monolith, and is fixed to an organic porous body composed of a continuous skeleton phase and a continuous pore phase, and the skeleton surface of the organic porous body. An organic porous body consisting of a continuous skeleton phase and a continuous pore phase, and a size formed on the skeleton surface of the organic porous body. A composite structure with a large number of protrusions having a thickness of 4 to 40 μm, and having an average pore diameter of 10 to 150 μm and a total pore volume of 0.5 to 5 ml / g in a water wet state, The ion exchange capacity per volume is 0.2 mg equivalent / ml or more, and the ion exchange groups are uniformly distributed in the composite structure. In the present specification, “particle bodies” and “projections” may be collectively referred to as “particle bodies”.

  The continuous skeleton phase and the continuous pore phase (dried body) of the organic porous body can be observed by an SEM image. Examples of the basic structure of the organic porous material include a continuous macropore structure and a co-continuous structure. The skeletal phase of the organic porous material appears as a columnar continuum, a concave wall continuum, or a composite thereof, and has a shape that is clearly different from a particle shape or a protrusion shape.

  As a preferable structure of the organic porous body, a continuous macropore structure (hereinafter referred to as “first organic porous ion”) in which bubble-shaped macropores overlap each other, and the overlapping portion becomes an opening having an average diameter of 30 to 150 μm in a wet state. And a three-dimensional continuous skeleton having an average thickness of 1 to 60 μm in a water-wet state, and three-dimensional continuous having an average diameter of 10 to 100 μm in a water-wet state between the skeletons. A co-continuous structure (hereinafter, also referred to as “second organic porous ion exchanger”).

  In the case of the first organic porous ion exchanger, the organic porous body is a continuous macropore structure in which bubble-shaped macropores are overlapped with each other, and the overlapping portions form openings (mesopores) having an average diameter of 30 to 150 μm in a wet state. It is. The average diameter of the opening of the composite monolith ion exchanger is larger than the average diameter of the opening of the composite monolith in a dry state because the entire composite monolith swells when an ion exchange group is introduced into the monolith. If the average diameter of the openings is less than 30 μm, the pressure loss during water flow is increased, which is not preferable. If the average diameter of the openings is too large, the contact between the ultrapure water and the monolith ion exchanger becomes insufficient. As a result, the removal efficiency of the ionic component is lowered, which is not preferable.

  In the present invention, the average diameter of the openings of the dry monolith intermediate, the average diameter of the pores or openings of the dry composite monolith, and the average diameter of the holes or openings of the dry composite monolith ion exchanger are: It is a value measured by the mercury intrusion method. Further, in the organic porous ion exchanger of the present invention, the average diameter of the pores or openings of the composite monolith ion exchanger in the water wet state is the average diameter of the pores or openings of the composite monolith ion exchanger in the dry state. It is a value calculated by multiplying the swelling rate. Specifically, the diameter of the composite monolith ion exchanger in the water wet state is x1 (mm), the diameter of the composite monolith ion exchanger in the dry state obtained by drying the composite monolith ion exchanger in the water wet state. And y1 (mm), and the average diameter of the pores or openings when the dry monolithic ion exchanger is measured by mercury porosimetry is z1 (μm) The average diameter (μm) of the holes or openings of the exchanger is calculated by the following formula “average diameter of holes or openings (μm) = z1 × (x1 / y1) of the composite monolith ion exchanger in a water-wet state”. The Also, the average diameter of the pores or openings of the dry composite monolith before introduction of the ion exchange group, and the water-wetting composite monolith ion relative to the dry composite monolith when the ion exchange group is introduced into the dry composite monolith When the swelling ratio of the exchanger is known, the average diameter of the pores or openings of the composite monolith in the dry state is multiplied by the swelling ratio to calculate the average diameter of the pores of the composite monolith ion exchanger in the water wet state. You can also.

  In the case of the second organic porous body ion exchanger, the organic porous body has a three-dimensionally continuous skeleton having an average diameter of 1 to 60 μm in a water-wet state, and an average diameter between the skeletons in a water-wet state. It is a co-continuous structure having three-dimensionally continuous pores of 10 to 100 μm. If the diameter of the three-dimensional continuous pores is less than 10 μm, the pressure loss during fluid permeation increases, which is not preferable. If the diameter exceeds 100 μm, contact between the fluid and the organic porous ion exchanger is not preferable. As a result, the ion exchange characteristics are not uniform, that is, the length of the ion exchange zone becomes long, and a small amount of adsorbed ions are likely to be leaked, which is not preferable.

  The average diameter of the co-continuous structure pores in the water-wet state is a value calculated by multiplying the average diameter of the pores of the composite monolith ion exchanger in the dry state measured by a known mercury intrusion method and the swelling ratio. It is. Specifically, the diameter of the composite monolith ion exchanger in the water wet state is x2 (mm), the diameter of the composite monolith ion exchanger in the dry state obtained by drying the composite monolith ion exchanger in the water wet state. Is y2 (mm), and the average diameter of the pores when the dried monolithic ion exchanger is measured by mercury porosimetry is z2 (μm), the pores of the composite monolith ion exchanger The average diameter (μm) in the water-wet state is calculated by the following formula: “Average diameter (μm) of the pores of the composite monolith ion exchanger in the water-wet state = z2 × (x2 / y2)”. In addition, the average diameter of the pores of the dry composite monolith before introduction of the ion exchange group, and the water-wet composite monolith ion exchanger with respect to the dry composite monolith when the ion exchange group is introduced into the dry composite monolith Can be calculated by multiplying the average diameter of the pores of the composite monolith in the dry state by the swelling ratio to calculate the average diameter of the pores of the composite monolith ion exchanger in the water-wet state. The average thickness of the skeleton of the co-continuous structure in the wet state is determined by performing SEM observation of the composite monolith ion exchanger in the dry state at least three times and measuring the thickness of the skeleton in the obtained image. The average value is calculated by multiplying the swelling ratio. Specifically, the diameter of the composite monolith ion exchanger in the water wet state is x3 (mm), the diameter of the composite monolith ion exchanger in the dry state obtained by drying the composite monolith ion exchanger in the water wet state. Y3 (mm), SEM observation of this dried composite monolith ion exchanger was performed 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 composite monolith ion exchanger in the water-wet state is expressed by the following formula: “average thickness of the skeleton of the continuous structure of the composite monolith ion exchanger in the water-wet state” (Μm) = z3 × (x3 / y3) ”. Further, the average thickness of the skeleton of the dry composite monolith before the introduction of the ion exchange groups, and the water-wet composite monolith ion exchanger with respect to the dry composite monolith when the ion exchange groups are introduced into the dry composite monolith Can be calculated by multiplying the average thickness of the skeleton of the composite monolith in the dry state by the swell ratio to the water-wet state of the skeleton of the composite monolith ion exchanger. The skeleton forming the co-continuous structure is rod-shaped and has a circular cross-sectional shape, but may have a cross-section with different diameters such as an elliptical cross-sectional shape. The thickness in this case is the average of the minor axis and the major axis.

  Further, if the diameter of the three-dimensionally continuous skeleton is less than 1 μm, the ion exchange capacity per volume is reduced, which is not preferable. If the diameter exceeds 60 μm, the uniformity of the ion exchange characteristics is lost, which is not preferable. .

  A preferable value of the average diameter of the pores of the composite monolith ion exchanger in a wet state with water is 10 to 120 μm. When the organic porous body constituting the composite monolith ion exchanger is the first organic porous body, the preferred pore diameter of the composite monolith ion exchanger is 30 to 120 μm, and the organic porous body constituting the composite monolith ion exchanger In the case of the second organic porous body, a preferable value of the pore diameter of the composite monolith ion exchanger is 10 to 90 μm.

  In the composite monolith ion exchanger according to the present invention, the diameter of the particles and the size of the protrusions in a wet state are 4 to 40 μm, preferably 4 to 30 μm, and particularly preferably 4 to 20 μm. In the present invention, both the particles and the protrusions are observed as protrusions on the surface of the skeleton, and the particles observed are referred to as particles, and the protrusions that are not granular are protrusions. Called the body. FIG. 19 shows a schematic cross-sectional view of the protrusion. As shown in FIGS. 19A to 19E, the protrusions protruding from the skeleton surface 61 are protrusions 62. The protrusions 62 are like the protrusions 62a shown in FIG. The shape close to a granular shape, a hemispherical shape like a projection 62b shown in (B), and a swell of the skeleton surface like a projection 62c shown in (C). In addition, the protrusion 61 has a shape that is longer in the direction perpendicular to the skeleton surface 61 than in the plane direction of the skeleton surface 61, like the protrusion 62d shown in FIG. There is a thing of the shape which protruded in the several direction like the protrusion 62e shown to (E). Further, the size of the protrusions is determined by the SEM image when observed by SEM, and indicates the length of the portion where the width of each protrusion is the largest in the SEM image.

  In the composite monolith ion exchanger according to the present invention, the proportion of 4 to 40 μm particles in a wet state in water is 70% or more, preferably 80% or more. In addition, the ratio which 4-40 micrometers particle bodies etc. occupy in the water wet state in all the particle bodies etc. points out the number ratio of 4-40 micrometers particle bodies etc. in the water wet state which occupy the number of all particle bodies. Further, the surface of the skeletal phase is covered by 40% or more, preferably 50% or more by the whole particles. The coverage ratio of the surface of the skeleton layer with particles or the like refers to the area ratio on the SEM image when the surface is observed by SEM, that is, the area ratio when the surface is viewed in plan. If the size of the particle covering the wall surface or the skeleton deviates from the above range, the effect of improving the contact efficiency between the fluid and the skeleton surface of the composite monolith ion exchanger and the inside of the skeleton is not preferable. In addition, all the particulate bodies etc. are all the particulate bodies formed on the surface of the skeleton layer including all the particulate bodies and protrusions in the size range other than the 4-40 μm particulate bodies in the wet state. And a protrusion.

  The diameter or size of the particles attached to the surface of the skeleton of the composite monolith ion exchanger in the water-wet state is the diameter or size of the particles obtained by observing the SEM image of the composite monolith ion exchanger in the dry state. Further, the value calculated by multiplying the swelling rate when the dry state is changed to the wet state, or the diameter or size of the particulates obtained by observing the SEM image of the composite monolith in the dry state before introducing the ion exchange group And a value calculated by multiplying the swelling ratio before and after introduction of the ion exchange group. Specifically, the diameter of the composite monolith ion exchanger in the water wet state is x4 (mm), the diameter of the composite monolith ion exchanger in the dry state obtained by drying the composite monolith ion exchanger in the water wet state. Is y4 (mm), and the diameter or size of the particles in the SEM image of the dried composite monolith ion exchanger observed by SEM is z4 (μm). The diameter or size (μm) of the particles of the monolith ion exchanger is expressed by the following formula: “diameter or size (μm) of the particles of the composite monolith ion exchanger in a water-wet state” = z4 × (x4 / y4) Is calculated. Then, the diameter or size of all particles observed in the SEM image of the composite monolith ion exchanger in the dry state is measured, and based on the value, all particles in one field of view SEM image, etc. The diameter or size of the water in a wet state is calculated. The SEM observation of the dried composite monolith ion exchanger is performed at least three times, and the diameter or size of the whole particle in the SEM image in the water-wet state is calculated in all fields of view. It is confirmed whether or not a particle body or the like at 4 to 40 μm is observed, and when it is confirmed in the entire visual field, the diameter or size is 4 to 40 μm in a wet state on the skeleton surface of the composite monolith ion exchanger. It is determined that the particle body at is formed. Further, according to the above, the diameter or size in the water wet state of all particles in the SEM image is calculated for each visual field, and the particle size of 4 to 40 μm in the water wet state occupying in the whole particles for each visual field. When the proportion of the particles, etc. is 40% or more in the wet state in all the particles in the entire visual field, the skeleton surface of the composite monolith ion exchanger is obtained. It is determined that the proportion of 4 to 40 μm particles in the wet state is 70% or more in all particles formed in the above. Further, according to the above, the coverage ratio of the surface of the skeletal layer with all particles in the SEM image was determined for each field of view, and the coverage ratio of the surface of the skeleton layer with all particles in all fields was 40% or more. In this case, it is determined that the ratio of the surface of the skeleton layer of the composite monolith ion exchanger covered with all the particulates is 40% or more. In addition, the diameter or size of the particles of the composite monolith in the dry state before the introduction of the ion exchange group and the composite monolith ion exchange in the wet state with respect to the dry composite monolith when the ion exchange group is introduced into the monolith in the dry state If the swelling rate of the body is known, the diameter or size of the particles of the composite monolith in the dry state is multiplied by the swelling rate to obtain the diameter or size of the particles of the composite monolith ion exchanger in the water wet state. In the same manner as described above, the diameter or size of the particles of the composite monolith ion exchanger in the water wet state, the ratio of the particles of 4 to 40 μm in the water wet state, etc. in the total particles, etc. In addition, the coverage ratio of the surface of the skeleton layer with particle bodies can be obtained.

  When the coverage of the skeletal phase surface with particles and the like is less than 40%, the effect of improving the contact efficiency between the fluid and the inside of the skeleton of the composite monolith ion exchanger and the skeleton surface is reduced, and the uniformity of the ion exchange behavior is reduced. Since it will be damaged, it is not preferable. Examples of the method for measuring the coverage with the above-mentioned particle bodies include an image analysis method using a monolith SEM image.

  The total pore volume of the composite monolith ion exchanger is the same as the total pore volume of the composite monolith. That is, even when the ion exchange group is introduced into the composite monolith to swell and increase the opening diameter, the total pore volume hardly changes because the skeletal phase is thick. If the total pore volume is less than 0.5 ml / g, the pressure loss during fluid permeation increases, which is not preferable. On the other hand, if the total pore volume exceeds 5 ml / g, the ion exchange capacity per volume decreases, which is not preferable. Note that the total pore volume of the composite monolith (monolith intermediate, composite monolith, composite monolith ion exchanger) is the same both in the dry state and in the water wet state.

  Note that the pressure loss when water is permeated through the composite monolith ion exchanger is the same as the pressure loss when water is permeated through the composite monolith.

  The composite monolith ion exchanger of the present invention has an ion exchange capacity per volume in a water-wet state of 0.2 mg equivalent / ml or more, preferably 0.3 to 1.8 mg equivalent / ml. If the ion exchange capacity per volume is less than 0.2 mg equivalent / ml, the amount of ultrapure water to be processed before breakthrough decreases, and the frequency of module replacement increases, which is not preferable. In addition, the ion exchange capacity per weight in the dry state of the composite monolith ion exchanger of the present invention is not particularly limited, but since the ion exchange groups are uniformly introduced to the skeleton surface and the skeleton inside the composite monolith, 5 mg equivalent / g. The ion exchange capacity of the organic porous material in which the ion exchange group is introduced only on the surface of the skeleton cannot be determined depending on the kind of the organic porous material or the ion exchange group, but is 500 μg equivalent / g at most.

  Examples of the ion exchange group to be introduced into the composite monolith of the present invention 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; a quaternary ammonium group and a tertiary amino group. And anion exchange groups such as secondary amino group, primary amino group, polyethyleneimine group, tertiary sulfonium group, and phosphonium group.

  In the composite monolith ion exchanger of the present invention, the introduced ion exchange groups are uniformly distributed not only on the surface of the skeleton of the composite monolith but also inside the skeleton phase. Here, “the ion exchange groups are uniformly distributed” means that the distribution of the ion exchange groups is uniformly distributed at least on the order of μm on the surface of the skeleton phase and inside the skeleton phase. The distribution of ion exchange groups can be confirmed relatively easily by using EPMA or the like. In addition, when the ion exchange groups are uniformly distributed not only on the surface of the composite monolith but also inside the skeleton phase, the physical and chemical properties of the surface and the interior can be made uniform, so that the swelling and shrinkage can be prevented. Durability is improved.

  The composite monolith ion exchanger of the present invention has a thickness of 1 mm or more, and is distinguished from a membrane-like porous body. If the thickness is less than 1 mm, the adsorption capacity per porous body is extremely lowered, which is not preferable. The thickness of the composite monolith ion exchanger is preferably 3 mm to 1000 mm. In addition, the composite monolith ion exchanger of the present invention has high mechanical strength because the basic structure of the skeleton is a continuous pore structure.

The composite monolith ion exchanger of the present invention is obtained by stirring a mixture of an oil-soluble monomer containing no ion exchange group, a first crosslinking agent having at least two or more vinyl groups in one molecule, a surfactant and water. Preparing a water-in-oil emulsion and then polymerizing the water-in-oil emulsion to obtain a monolithic organic porous intermediate having a continuous macropore structure with a total pore volume of 5 to 30 ml / g, vinyl monomer, A mixture comprising a second crosslinking agent having at least two vinyl groups in one molecule, an organic solvent that dissolves the vinyl monomer or the second crosslinking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer, and a polymerization initiator. Step II for preparing the compound II. 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 II When the monolithic organic porous material is produced by performing the IV step of introducing an ion exchange group into the monolithic organic porous material obtained in the steps I and III, the following (1) to (5):
(1) The polymerization temperature in step III is at least 5 ° C. lower than the 10-hour half-life temperature of the polymerization initiator;
(2) The mol% of the second cross-linking agent used in step II is at least twice the mol% of the first cross-linking agent used in step I;
(3) The vinyl monomer used in Step II is a vinyl monomer having a structure different from that of the oil-soluble monomer used in Step I;
(4) The organic solvent used in step II is a polyether having a molecular weight of 200 or more;
(5) The concentration of the vinyl monomer used in Step II is 30% by weight or less in the mixture of Step II;
It is obtained by performing Step II or Step III under the conditions satisfying at least one of the above conditions.

(Method for producing monolith intermediate)
In the method for producing a monolith according to the present invention, in the step I, an oil-soluble monomer not containing an ion exchange group, a first crosslinking agent having at least two or more vinyl groups in one molecule, a mixture of a surfactant and water are stirred. In this step, a water-in-oil emulsion is prepared, and then the water-in-oil emulsion is polymerized to obtain a monolith intermediate having a continuous macropore structure having a total pore volume of 5 to 30 ml / g. The step I for obtaining the monolith intermediate may be performed according to the method described in JP-A-2002-306976.

  Examples of the oil-soluble monomer that does not contain an ion exchange group include an oleophilic monomer that 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. 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.

  Examples of the first crosslinking agent having at least two or more vinyl groups in one molecule include divinylbenzene, divinylnaphthalene, divinylbiphenyl, and ethylene glycol dimethacrylate. These crosslinking agents can be used singly or in combination of two or more. A preferred first cross-linking agent is an aromatic polyvinyl compound such as divinylbenzene, divinylnaphthalene, and divinylbiphenyl because of its high mechanical strength. The amount of the first crosslinking agent used is 0.3 to 10 mol%, particularly 0.3 to 5 mol%, and more preferably 0.3 to 3 mol%, based on the total amount of the vinyl monomer and the first crosslinking agent. Is preferred. If the amount of the first 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 10 mol%, the monolith becomes more brittle and the flexibility is lost, and the amount of ion exchange groups introduced decreases, which is not preferable.

  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, 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, hydrogen peroxide-ferrous chloride, sodium persulfate- Examples include acidic sodium sulfite.

  There is no particular limitation on the mixing method when mixing the oil-soluble monomer containing no ion exchange group, the first cross-linking agent, the surfactant, water and the polymerization initiator to form a water-in-oil emulsion, A method of mixing components all at once, an oil-soluble monomer, a first crosslinking agent, a surfactant, an oil-soluble component that is an oil-soluble polymerization initiator, and a water-soluble component that is water or a water-soluble polymerization initiator For example, a method in which each component is mixed after being uniformly dissolved separately 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, particles or the like are formed on the surface of the skeleton phase of the continuous macropore structure using the structure of the monolith intermediate as a template, or particles or the like are formed on the surface of the skeleton phase of the co-continuous structure. Or 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 10 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. On the other hand, if it exceeds 10 mol%, the porous body becomes brittle and the flexibility is lost, which is not preferable.

  The total pore volume of the monolith intermediate is 5-30 ml / g, preferably 6-28 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 during fluid permeation 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 tends to be non-uniform, and in some cases, the structure collapses, which is not preferable. In order to set the total pore volume of the monolith intermediate in the above numerical range, the ratio (weight) of the monomer to water may be set to approximately 1: 5 to 1:35.

  When the ratio of this monomer to water is approximately 1: 5 to 1:20, a monolith intermediate having a total pore volume of 5 to 16 ml / g and a continuous macropore structure can be obtained and obtained through Step III. The obtained composite monolithic organic porous body is the first organic porous body. Further, if the blending ratio is approximately 1:20 to 1:35, a monolith intermediate having a total pore volume of more than 16 ml / g and a continuous macropore structure of 30 ml / g or less can be obtained. The organic porous body of the composite monolith obtained through the above is obtained as the second organic porous body.

  Moreover, the average diameter of the opening (mesopore) which is an overlap part of a macropore and a macropore is 20-100 micrometers in a dry state in a monolith intermediate. When 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 at the time of passing water becomes large, 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, resulting in insufficient contact between the water to be treated and the monolith ion exchanger. Since removal efficiency falls, it 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.

(Production method of composite monolith)
Step II is an organic solvent in which a vinyl monomer, a second cross-linking agent having at least two vinyl groups in one molecule, a vinyl monomer or a second cross-linking agent dissolves, but a polymer formed by polymerization of the vinyl monomer does not dissolve. And a step of preparing a mixture comprising a polymerization initiator. 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 that contains a polymerizable vinyl group in the molecule and has high solubility in an organic solvent. 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, particles cannot be formed in the skeleton of the produced monolith, and the adsorption capacity per volume and the ion exchange capacity per volume after the introduction of ion exchange groups are reduced. Since it becomes small, it is not preferable. On the other hand, if the amount of vinyl monomer added exceeds 40 times, the opening diameter becomes small and the pressure loss during fluid permeation increases, which is not preferable.

  As the second crosslinking agent used in Step II, one having at least two polymerizable vinyl groups in the molecule and having high solubility in an organic solvent is preferably used. Specific examples of the second crosslinking agent include divinylbenzene, divinylnaphthalene, divinylbiphenyl, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, butanediol diacrylate, and the like. These 2nd crosslinking agents can be used individually by 1 type or in combination of 2 or more types. A preferred second crosslinking agent is an aromatic polyvinyl compound such as divinylbenzene, divinylnaphthalene, and divinylbiphenyl because of its high mechanical strength and stability to hydrolysis. The amount of the second crosslinking agent used is preferably 0.3 to 20 mol%, particularly 0.3 to 10 mol%, based on the total amount of the vinyl monomer and the second 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 20 mol%, the monolith becomes more brittle and the flexibility is lost, and the amount of ion exchange groups introduced decreases, which is not preferable.

  The organic solvent used in step II is an organic solvent that dissolves the vinyl monomer and the second cross-linking agent but does not dissolve the polymer formed by polymerization of the vinyl monomer, in other words, a poor solvent for the polymer formed by polymerization of the vinyl monomer. It is. 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, propylene glycol, tetramethylene glycol; chain (poly) ethers such as diethyl ether, butyl cellosolve, polyethylene glycol, polypropylene glycol, polytetramethylene glycol Chain saturated hydrocarbons such as hexane, heptane, octane, isooctane, decane, dodecane, etc .; Ethyl acetate, isopropyl acetate, cellosolve acetate, ethyl propionate, etc. Ethers, and the like. 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 5 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 5% by weight, the polymerization rate is lowered, which is not preferable. 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, tetramethylthiuram disulfide and the like. The amount of 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 second crosslinking agent. .

  In step III, the mixture obtained in step II is allowed to stand, and in the presence of the monolith intermediate obtained in step I, polymerization is performed to obtain a composite monolith. 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 second cross-linking agent are allowed to stand in a specific organic solvent in the absence of a monolith intermediate, a particle aggregation type monolithic organic material is obtained. A porous 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 specific skeleton described above is lost. A monolith having a structure is obtained.

  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 monolith after polymerization does not receive any pressure from the inner wall of the vessel and enters the reaction vessel without any gap, so that 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 specific 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, or the like is used as an initiator, an inert atmosphere What is necessary is just to heat-polymerize at 20-100 degreeC for 1 to 48 hours in the lower sealed container. By heat polymerization, the vinyl monomer adsorbed and distributed on the skeleton of the monolith intermediate and the crosslinking agent are polymerized in the skeleton to form the specific skeleton structure. After completion of the polymerization, the content is taken out and extracted with a solvent such as acetone for the purpose of removing unreacted vinyl monomer and organic solvent to obtain a monolith having a specific skeleton structure.

  When the above-mentioned composite monolith is produced, the skeleton, which is the characteristic structure of the present invention, is obtained by performing the II step or the III step under the conditions satisfying at least one of the following conditions (1) to (5). A composite monolith having particles or the like formed on the surface can be produced.

(1) The polymerization temperature in step III is a temperature that is at least 5 ° C. lower than the 10-hour half-life temperature of the polymerization initiator.
(2) The mol% of the second cross-linking agent used in step II is at least twice the mol% of the first cross-linking agent used in step I.
(3) The vinyl monomer used in step II is a vinyl monomer having a structure different from that of the oil-soluble monomer used in step I.
(4) The organic solvent used in step II is a polyether having a molecular weight of 200 or more.
(5) The concentration of the vinyl monomer used in Step II is 30% by weight or less in the mixture of Step II.

(Description of (1) above)
The 10-hour half temperature is a characteristic value of the polymerization initiator, and if the polymerization initiator to be used is determined, the 10-hour half temperature can be known. Moreover, if there exists desired 10-hour half temperature, the polymerization initiator applicable to it can be selected. In step III, the polymerization rate is lowered by lowering the polymerization temperature, and particles and the like can be formed on the surface of the skeleton phase. The reason for this is that the monomer concentration drop inside the skeleton phase of the monolith intermediate becomes gradual, and the monomer distribution rate from the liquid phase part to the monolith intermediate decreases, so the surplus monomer is on the surface of the skeleton layer of the monolith intermediate. It is thought that it was concentrated in the vicinity and polymerized in situ.

  The preferred polymerization temperature is a temperature that is at least 10 ° C. lower than the 10-hour half-life temperature of the polymerization initiator used. Although the lower limit of the polymerization temperature is not particularly limited, the polymerization rate decreases as the temperature decreases, and the polymerization time becomes unacceptably long. Therefore, the polymerization temperature is 5 to 20 ° C. with respect to the 10-hour half temperature. It is preferable to set to a low range.

(Description of (2))
When the mol% of the second cross-linking agent used in Step II is set to be twice or more of the mol% of the first cross-linking agent used in Step I, the composite monolith of the present invention is obtained. The reason for this is that the compatibility between the monolith intermediate and the polymer produced by impregnation polymerization is reduced and phase separation proceeds, so the polymer produced by impregnation polymerization is excluded in the vicinity of the surface of the skeleton phase of the monolith intermediate, It is considered that irregularities such as particles are formed on the surface. In addition, mol% of a crosslinking agent is a crosslinking density mol%, Comprising: The amount of crosslinking agents (mol%) with respect to the total amount of a vinyl monomer and a crosslinking agent is said.

  The upper limit of the second crosslinker mol% used in step II is not particularly limited, but if the second crosslinker mol% is extremely large, cracks occur in the monolith after polymerization, and the brittleness of the monolith proceeds and flexibility is increased. This is not preferable because it causes a problem that the amount of ion exchange groups to be lost is reduced. A preferred multiple of the second crosslinking agent mol% is 2 to 10 times. On the other hand, even when the mol% of the first cross-linking agent used in step I is set to be twice or more the mol% of the second cross-linking agent used in step II, the formation of particles on the surface of the skeleton phase does not occur. The composite monolith of the present invention cannot be obtained.

(Explanation of (3))
When the vinyl monomer used in Step II is a vinyl monomer having a structure different from that of the oil-soluble monomer used in Step I, the composite monolith of the present invention is obtained. For example, if the structures of vinyl monomers are slightly different, such as styrene and vinyl benzyl chloride, a composite monolith having particles or the like formed on the surface of the skeleton phase is generated. In general, two types of homopolymers obtained from two types of monomers that are slightly different in structure are not compatible with each other. Therefore, a monomer having a structure different from that of the monomer used for forming the monolith intermediate used in Step I, that is, a monomer other than the monomer used for forming the monolith intermediate used in Step I is used in Step II to polymerize in Step III. The monomer used in Step II is uniformly distributed and impregnated into the monolith intermediate, but when the polymerization proceeds and the polymer is produced, the produced polymer is not compatible with the monolith intermediate. Separation proceeds, and the produced polymer is considered to be excluded in the vicinity of the surface of the skeleton phase of the monolith intermediate, and irregularities such as particles are formed on the surface of the skeleton phase.

(Explanation of (4))
When the organic solvent used in step II is a polyether having a molecular weight of 200 or more, the composite monolith of the present invention is obtained. Polyethers have a relatively high affinity with monolith intermediates, especially low molecular weight cyclic polyethers are good solvents for polystyrene, and low molecular weight chain polyethers are not good solvents but have considerable affinity. . However, as the molecular weight of the polyether increases, the affinity with the monolith intermediate dramatically decreases and shows little affinity with the monolith intermediate. When such a solvent having poor affinity is used as the organic solvent, diffusion of the monomer into the skeleton of the monolith intermediate is inhibited, and as a result, the monomer is polymerized only near the surface of the skeleton of the monolith intermediate. It is considered that particles and the like are formed on the phase surface and irregularities are formed on the skeleton surface.

  The upper limit of the molecular weight of the polyether is not particularly limited as long as it is 200 or more. However, when the molecular weight is too high, the viscosity of the mixture prepared in the step II becomes high, and it is difficult to impregnate the monolith intermediate. Therefore, it is not preferable. The molecular weight of the preferred polyether is 200 to 100,000, particularly preferably 200 to 10,000. The terminal structure of the polyether may be an unmodified hydroxyl group, etherified with an alkyl group such as a methyl group or an ethyl group, or esterified with acetic acid, oleic acid, lauric acid, stearic acid, or the like. It may be made.

(Explanation of (5))
When the concentration of the vinyl monomer used in Step II is 30% by weight or less in the mixture in Step II, the composite monolith of the present invention is obtained. By reducing the monomer concentration in the step II, the polymerization rate is reduced, and for the same reason as the above (1), particles and the like can be formed on the surface of the skeleton phase, and irregularities can be formed on the surface of the skeleton phase. . Although the lower limit of the monomer concentration is not particularly limited, the polymerization rate decreases as the monomer concentration decreases and the polymerization time becomes unacceptably long, so the monomer concentration may be set to 10 to 30% by weight. preferable.

  The composite monolith obtained in the step III includes an organic porous body composed of a continuous skeleton phase and a continuous pore phase, a large number of particles fixed to the skeleton surface of the organic porous body, or a skeleton surface of the organic porous body. It is a composite structure with a number of protrusions formed on it. The continuous skeleton phase and the continuous pore phase of the organic porous body can be observed by SEM images. The basic structure of the organic porous body is a continuous macropore structure or a co-continuous structure.

  The continuous macropore structure in the composite monolith is such that bubble-shaped macropores overlap each other, and the overlapping portion becomes an opening having an average diameter of 20 to 100 μm in a dry state. The bicontinuous structure in the composite monolith has an average thickness. Is composed of a three-dimensionally continuous skeleton of 0.8 to 40 μm in a dry state and three-dimensionally continuous pores having an average diameter of 8 to 80 μm by drying between the skeletons.

  Step IV is a step of introducing an ion exchange group into the composite monolith obtained in step III. According to this introduction method, the porous structure of the obtained composite monolith ion exchanger can be strictly controlled.

  The method for introducing an ion exchange group into the composite monolith is not particularly limited, and a known method such as polymer reaction or graft polymerization can be used. For example, as a method of introducing a sulfonic acid group, if the composite monolith is a styrene-divinylbenzene copolymer, etc., a method of sulfonation using chlorosulfuric acid, concentrated sulfuric acid, or fuming sulfuric acid; radical initiating groups uniformly on the composite monolith And a method of grafting sodium styrene sulfonate or acrylamido-2-methylpropane sulfonic acid by introducing a chain transfer group into the skeleton surface or inside the skeleton; Similarly, after graft polymerization of glycidyl methacrylate, the sulfonic acid group is converted by functional group conversion. The method etc. which introduce | transduce are mentioned. In addition, as a method of introducing a quaternary ammonium group, if the composite monolith is a styrene-divinylbenzene copolymer or the like, a method of introducing a chloromethyl group with chloromethyl methyl ether or the like and then reacting with a tertiary amine; A method of producing monolith by copolymerization of chloromethylstyrene and divinylbenzene and reacting with a tertiary amine; uniformly introducing a radical initiating group or chain transfer group into the monolith on the skeleton surface and inside the skeleton, and N, N, N- Examples include a method of graft polymerization of trimethylammonium ethyl acrylate or N, N, N-trimethylammonium propylacrylamide; a method of grafting glycidyl methacrylate in the same manner and then introducing a quaternary ammonium group by functional group conversion. Among these methods, the method of introducing a sulfonic acid group includes a method of introducing a sulfonic acid group into a styrene-divinylbenzene copolymer using chlorosulfuric acid, and a method of introducing a quaternary ammonium group includes styrene. -Introducing a chloromethyl group into the divinylbenzene copolymer with chloromethyl methyl ether, etc., then reacting with a tertiary amine, or producing a monolith by copolymerization of chloromethylstyrene and divinylbenzene and reacting with a tertiary amine The method is preferable in that the ion exchange group can be introduced uniformly and quantitatively. The 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 ester groups; quaternary ammonium groups, tertiary amino groups, and secondary amino groups. Groups, primary amino groups, polyethyleneimine groups, tertiary sulfonium groups, phosphonium groups and the like.

  The module form of the ion adsorption module is not particularly limited, and a method of passing water through a simple cylindrical packed bed in an upward flow or a downward flow, passing water from the outer circumferential direction to the inner cylinder through the cylindrical packed bed. An external pressure system that performs water flow, an internal pressure system that allows water to flow in the opposite direction, a tubular system that fills a large number of elongated cylindrical porous ion exchangers, and allows water to flow through an internal pressure system or an external pressure system, and a flat membrane that uses a sheet-shaped packed bed And a pleating method in which a flat membrane is processed into a folded shape. Further, the shape of the porous ion exchanger to be filled is appropriately selected from block shape, sheet shape, columnar shape, cylindrical shape, etc. according to the method of the module. Examples thereof include a method of cutting and molding the exchanger, and a method in which the emulsion is filled in a mold having a desired shape in the manufacturing process and polymerization is performed in the mold.

  The kind and packing form of the porous ion exchanger filled in the ion adsorption module can be arbitrarily determined according to the purpose of use, that is, the kind of impurities to be adsorbed. That is, the module can be filled with a porous anion exchanger, a porous cation exchanger, and a porous chelate adsorbent alone or in combination. Moreover, as a method of mixing, there are lamination in the direction of water flow, mixed filling of small block ion exchangers, and the like. Furthermore, a module in which a porous anion exchanger, a porous cation exchanger, and a porous chelate adsorbent are packed alone can be combined in any order. Among these, it is preferable that the module is used by filling the porous cation exchanger alone, because metals that particularly affect the semiconductor device can be effectively removed.

  Next, a method for producing ultrapure water using the ultrapure water production apparatus 10a of FIG. 17 will be described. First, treated water 21 such as industrial water, city water, well water, river water, etc. is treated by a pretreatment device 20 comprising a coagulation filtration device 22 and an activated carbon tower 23 to remove most of suspended matter and organic matter in the treated water. Then, the pretreated water is treated with a reverse osmosis membrane module 31 loaded with a reverse osmosis membrane to remove ions and TOC, and then treated with an ion exchange device 32 to obtain primary pure water 33. The primary pure water 33 is temporarily stored in a primary pure water storage tank 34, and is composed of a secondary pure water comprising an ultraviolet oxidation device 51, a non-regenerative cartridge polisher 52 filled with an ion exchange resin, and an ultrafiltration membrane device 53. By being treated by the water production apparatus 50, ultrapure water 54 from which impurities such as fine particles, colloidal substances, organic substances, metals and ions remaining in the primary pure water are removed as much as possible is obtained. When the ultrapure water 54 is supplied to the ion adsorption module, it circulates in the open cell structure of the organic porous ion exchanger, and both fine particles and ionic impurities are removed. The treated water of the ion adsorption module 6 from which impurities have been removed is used for cleaning semiconductor devices at each use point 4, and the remaining ultrapure water is circulated to the primary pure water storage tank 34. As described above, since the ion adsorption module 6 is filled with the porous ion exchanger having the specific structure, it removes both fine particles and ion components contained in the ultrapure water so that a highly integrated device can be used. A high purity suitable for production and the like can be stably maintained over a long period of time, and the replacement frequency of the module can be significantly reduced.

EXAMPLES Next, the present invention will be specifically described with reference to examples. However, this is merely an example and does not limit the present invention.
Reference example 1

(Step I; production of monolith intermediate)
9.28 g of styrene, 0.19 g of divinylbenzene, 0.50 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, 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 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 40 μm, and the total pore volume was 15.8 ml / g.

(Manufacture of composite monolith)
Next, 36.0 g of styrene, 4.0 g of divinylbenzene, 60 g of 1-decanol, and 0.4 g of 2,2′-azobis (2,4-dimethylvaleronitrile) were mixed and dissolved uniformly (step II). The 10-hour half-life temperature of 2,2′-azobis (2,4-dimethylvaleronitrile) used as the polymerization initiator was 51 ° C. The amount of divinylbenzene used is 6.6 mol% with respect to the total amount of styrene and divinylbenzene used in Step II, while the crosslink density of the monolith intermediate is 1.3 mol%, and the crosslink density ratio is 5.1 times. Met. 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 3.2 g was collected. The separated monolith intermediate is placed in a reaction vessel having an inner diameter of 73 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).

  The results of observing the internal structure of the composite monolith (dried body) composed of the styrene / divinylbenzene copolymer thus obtained by SEM are shown in FIGS. The SEM images in FIGS. 1 to 3 are different in magnification, and are images at arbitrary positions on a cut surface obtained by cutting a monolith at an arbitrary position. As apparent from FIGS. 1 to 3, the composite monolith has a continuous macropore structure, and the surface of the skeletal phase constituting the continuous macropore structure is coated with particles having an average particle diameter of 4 μm. The particle coverage of the skeleton surface by the body and the like was 80%. Moreover, the ratio for which the particle body with a particle size of 3-5 micrometers occupied to the whole particle body was 90%.

  Moreover, the average diameter of the opening of the composite monolith measured by mercury porosimetry was 16 μm, and the total pore volume was 2.3 ml / g. The results are summarized in Tables 1 and 2. In Table 1, the preparation column shows the vinyl monomer, the crosslinking agent, the organic solvent used in Step II, and the monolith intermediate obtained in Step I in order from the left. Further, the particle bodies and the like are shown as particles.

(Production of complex monolith cation exchanger)
The composite 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 19.6 g. To this, 1500 ml of dichloromethane was added and heated at 35 ° C. for 1 hour, then cooled to 10 ° C. or less, 98.9 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 composite monolith cation exchanger.

  The swelling rate before and after the reaction of the obtained cation exchanger was 1.3 times, and the ion exchange capacity per volume was 1.11 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 21 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 particle size of the particles was 5 μm. The particle coverage of the skeletal surface with all particles was 80%, and the total pore volume was 2.3 ml / g. Moreover, the ratio for which the particle body of 4-7 micrometers of particle | grains accounts to the whole particle body was 90%. The differential pressure coefficient, which is an index of pressure loss when water is permeated, is 0.057 MPa / m · LV, which is a lower pressure loss than that required for practical use. It was. Further, the length of the ion exchange zone was 9 mm, showing a remarkably short value. The results are summarized in Table 2.

  Next, in order to confirm the distribution state of the sulfonic acid group in the composite monolith cation exchanger, the distribution state of sulfur atoms was observed by EPMA. The results are shown in FIGS. 4 and 5, the left and right photographs correspond to each other. FIG. 4 shows the distribution of sulfur atoms on the surface of the cation exchanger, and FIG. 5 shows the distribution of sulfur atoms in the cross-section (thickness) direction of the cation exchanger. 4 and 5, it can be seen that the sulfonic acid groups are uniformly introduced on the skeleton surface of the cation exchanger and inside the skeleton (cross-sectional direction).

Reference Examples 2-5
(Manufacture of composite monolith)
The amount of vinyl monomer used, the amount of crosslinking agent used, the type and amount of organic solvent used, the porous structure of the monolith intermediate that coexists during polymerization in step III, the crosslinking density and the amount used, and the polymerization temperature are shown in Table 1. 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. Moreover, the result of having observed the internal structure of composite monolith (dry body) by SEM is shown in FIGS. 6 to 8 are of Reference Example 2, FIGS. 9 and 10 are of Reference Example 3, FIG. 11 is of Reference Example 4, and FIGS. 12 and 13 are of Reference Example 5. For Reference Example 2, the crosslinking density ratio (2.5 times), for Reference Example 3, the type of organic solvent (PEG; molecular weight 400), for Reference Example 4, the vinyl monomer concentration (28.0%), Reference Example For No. 5, the polymerization temperature (40 ° C .; 11 ° C. lower than the 10-hour half-life temperature of the polymerization initiator) was produced under conditions satisfying the production conditions of the present invention. From FIG. 6 to FIG. 13, what adhered to the skeleton surface of the composite monoliths of Reference Examples 3 to 5 were protrusions rather than particles. The “particle average diameter” of the protrusion is the average diameter of the protrusions (maximum diameter). From FIG. 6 to FIG. 13 and Table 2, the average diameter of the particles adhering to the surface of the monolith skeleton of Reference Examples 2 to 6 is 3 to 8 μm, and the particle coverage of the skeleton surface by all particles is 50 to 95%. there were. In addition, the proportion of Reference Example 2 in which particles having a particle diameter of 3 to 6 μm occupy the entire particle body is 80%, and the ratio of Reference Example 3 in which protrusions having a particle diameter of 3 to 10 μm occupy the entire particle is 80%. In Reference Example 4, the proportion of particles having a particle diameter of 3 to 5 μm in the total particle body was 90%, and in Reference Example 5, the proportion of particles having a particle diameter of 3 to 7 μm in the entire particle body was 90%. .

(Production of complex monolith cation exchanger)
The composite monolith produced by the above method was reacted with chlorosulfuric acid in the same manner as in Reference Example 1 to produce a composite monolith cation exchanger. The results are shown in Table 2. The average diameter of the continuous pores of the composite monolith cation exchanger in Reference Examples 2 to 5 is 21 to 52 μm, the average diameter of the particles attached to the skeleton surface is 5 to 13 μm, the skeleton surface due to all the particles, etc. The particle coverage was as high as 50 to 95%, the differential pressure coefficient was as small as 0.010 to 0.057 MPa / m · LV, and the ion exchange zone length was as extremely small as 8 to 12 mm. Moreover, the ratio for which the particle body with a particle size of 5-10 micrometers occupied to the whole particle body was 90%.
Reference Example 6

(Manufacture of composite monolith)
Table 1 shows the type and amount of vinyl monomer used, amount of crosslinking agent used, type and amount of organic solvent, monolith intermediate porous structure coexisting during polymerization in step III, crosslinking density and 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. Moreover, the result of having observed the internal structure of composite monolith (dry body) by SEM is shown in FIGS. What adhered to the skeleton surface of the composite monolith of Reference Example 6 was a protrusion. In the monolith of Reference Example 6, the average diameter of the maximum diameter of the protrusions formed on the surface was 10 μm, and the particle coverage of the skeletal surface with all the particulates was 100%. Moreover, the ratio for which the particle body with a particle size of 6-12 micrometers occupied to the whole particle body was 80%.

(Production of complex monolith anion exchanger)
The composite 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 composite monolith was 17.9 g. To this was added 1500 ml of tetrahydrofuran, heated at 40 ° C. for 1 hour, cooled to 10 ° C. or lower, gradually added 114.5 g of a 30% trimethylamine aqueous solution, heated to react at 40 ° C. for 24 hours. After completion of the reaction, the resultant was washed with methanol to remove tetrahydrofuran, and further washed with pure water to obtain a monolith anion exchanger.

  The obtained composite anion exchanger had a swelling ratio of 2.0 times before and after the reaction, and the ion exchange capacity per volume was 0.32 mg equivalent / ml in a water-wet state. The average diameter of the continuous pores of the organic porous ion exchanger in the water wet state was 58 μm as estimated from the value of the monolith and the swelling ratio of the monolith anion exchanger in the water wet state. The average diameter of the body was 20 μm, the particle coverage of the skeletal surface with all particles was 100%, and the total pore volume was 2.1 ml / g. The ion exchange zone length was as short as 16 mm. The differential pressure coefficient, which is an index of pressure loss when water is permeated, is 0.041 MPa / m · LV, which is a lower pressure loss than that required for practical use. It was. Moreover, the ratio for which the particle body with a particle size of 12-24 micrometers occupied to the whole particle body was 80%. The results are summarized in Table 2.

  Next, in order to confirm the distribution state of the quaternary ammonium groups in the porous anion exchanger, the anion exchanger was treated with an aqueous hydrochloric acid solution to form a chloride form, and then the distribution state of chlorine atoms was observed by EPMA. As a result, it was confirmed that the chlorine atoms were uniformly distributed not only on the skeleton surface of the anion exchanger but also inside the skeleton, and the quaternary ammonium groups were uniformly introduced into the anion exchanger.

Reference Example 7
(Manufacture of monoliths)
Except for changing the usage amount of the vinyl monomer, the usage amount of the crosslinking agent, the type and usage amount of the organic solvent, and the usage amount of the monolith intermediate coexisting during the polymerization in Step III to the blending amounts shown in Table 1, Example 1 and A monolith was produced in a similar manner. The results are shown in Tables 1 and 2. From the SEM photograph (not shown), the formation of particles and protrusions was not observed at all on the skeleton surface. From Table 1 and Table 2, when a monolith is produced under conditions deviating from the specific production conditions of the present invention, that is, conditions deviating from the requirements (1) to (5) above, particle formation on the surface of the monolith skeleton is caused. It turns out that it is not recognized.

(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. The results are shown in Table 2. The obtained monolith cation exchanger had an ion exchange zone length of 26 mm, which was a large value as compared with Reference Examples 1-6.

Reference Examples 8-10
(Manufacture of monoliths)
The amount of vinyl monomer used, the amount of crosslinking agent used, the type and amount of organic solvent used, the porous structure of the monolith intermediate that coexists during polymerization in step III, the crosslinking density, and the amount used were changed to the amounts shown in Table 1. Produced a monolith in the same manner as in Reference Example 1. The results are shown in Tables 1 and 2. For Reference Example 8, the crosslinking density ratio (0.2 times), for Reference Example 9, the type of organic solvent (2- (2-methoxyethoxy) ethanol; molecular weight 120), and for Reference Example 10, the polymerization temperature (50 C .: 1 ° C. lower than the 10-hour half-life temperature of the polymerization initiator) was produced under conditions that did not satisfy the production conditions of the present invention. The results are shown in Table 2. For the monoliths of Reference Examples 8 and 10, there was no particle formation on the skeleton surface. In Reference Example 9, the isolated product was transparent, and the porous structure was collapsed and disappeared.

(Production of monolith cation exchanger)
Except for Reference Example 9, the organic porous material produced by the above method was reacted with chlorosulfuric acid in the same manner as in Reference Example 7 to produce a monolith cation exchanger. The results are shown in Table 2. The obtained monolith cation exchanger had an ion exchange zone length of 23 to 26 mm, which was a large value as compared with Reference Examples 1 to 6.

Reference Example 11
(Manufacture of monoliths)
Reference Example 7 except that the amount of vinyl monomer used, the amount of crosslinking agent used, the amount of organic solvent used, the porous structure of monolith intermediate coexisting during polymerization in step III and the amount used were changed to the amounts shown in Table 1. A monolith was produced in the same manner as described above. The results are shown in Tables 1 and 2, and it can be seen that when a monolith is produced outside the specific production conditions of the present invention, no particle formation is observed on the surface of the monolith skeleton.

(Production of monolith anion exchanger)
The monolith produced by the above method was cut into a disk shape having a diameter of 70 mm and a thickness of about 15 mm. To this, 1400 ml of dimethoxymethane and 20 ml of tin tetrachloride were added, and 560 ml of chlorosulfuric acid was added dropwise under ice cooling. After completion of the dropping, the temperature was raised and the reaction was carried out at 35 ° C. for 5 hours to introduce a chloromethyl group. After completion of the reaction, the mother liquor was extracted with a siphon, washed with a mixed solvent of THF / water = 2/1, and further washed with THF. To this chloromethylated monolith, 1000 ml of THF and 600 ml of a 30% trimethylamine aqueous solution were added and reacted at 60 ° C. for 6 hours. After completion of the reaction, the product was washed with a methanol / water mixed solvent, then washed with pure water and isolated. The results are shown in Table 2. The obtained monolith anion exchanger had an ion exchange zone length of 47 mm, which was a large value compared with Reference Examples 1-6. In Tables 1 and 2, the mesopore diameter and pore value are average values.

Reference Example 12
(Production of monolithic organic porous cation exchanger (known))
27.7 g of styrene, 6.9 g of divinylbenzene, 0.14 g of azobisisobutyronitrile (ABIBN) and 3.8 g of sorbitan monooleate were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / azobisisobutyronitrile / sorbitan monooleate mixture is added to 450 ml of pure water, and stirred for 2 minutes at 20,000 rpm with a homogenizer, and a water-in-oil emulsion. Got. After emulsification, the water-in-oil emulsion was transferred to a stainless steel autoclave, sufficiently substituted with nitrogen, sealed, and allowed to polymerize at 60 ° C. for 24 hours. After completion of the polymerization, the content was taken out, extracted with Soxhlet for 18 hours with isopropanol, unreacted monomer and sorbitan monooleate were removed, and dried under reduced pressure at 40 ° C. overnight. After separating 11.5 g of an organic porous material containing 14 mol% of a crosslinking component composed of the styrene / divinylbenzene copolymer thus obtained, 800 ml of dichloroethane was added, and the mixture was heated at 60 ° C. for 30 minutes. After cooling to room temperature, 59.1 g of chlorosulfuric acid was gradually added and reacted at room temperature for 24 hours. Thereafter, acetic acid was added, the reaction product was poured into a large amount of water, washed with water and dried to obtain a porous cation exchanger. The ion exchange capacity of this porous body is 4.4 mg equivalent / g in terms of dry porous body and 0.32 mg equivalent / ml in terms of water-wet volume. By mapping sulfur atoms using EPMA, sulfonic acid It was confirmed that the group was uniformly introduced into the porous body. Further, as a result of SEM observation, the internal structure of this organic porous body has an open cell structure, most of the macropores having an average diameter of 30 μm overlap, and the pore diameter of the mesopore formed by the overlap of the macropores and the macropores is 5 μm. The total pore volume was 10.1 ml / g, and the BET specific surface area was 10 m ² / g.

(Production example 1 of ion adsorption module)
The porous ion exchanger of Reference Example 2 was cut in a wet state to form a cylindrical porous ion exchanger having a diameter of 5 cm and a height of 5 cm, packed in a high-density polyethylene column having an inner diameter of 5 cm, and 1 mol / L nitric acid. After regeneration, it was thoroughly washed with ultrapure water to obtain a regenerated form, and an ion adsorption module was obtained.

(Water flow test 1)
Using the apparatus shown in FIG. 18, it was confirmed that sodium hydroxide was added to pure water to make simulated contaminated pure water, and this was passed through an ion adsorption module to obtain good outlet water quality. Industrial water is used as raw water, which is passed through an ion exchanger 42 and a cartridge polisher 43 to obtain pure water having a specific resistance of 18.2 MΩ-cm. A sodium hydroxide aqueous solution is supplied from the sodium hydroxide injection facility 44 to the pure water. This was injected to obtain simulated contaminated pure water having a sodium concentration of 1.0 μg / L. This simulated contaminated pure water was passed through the ion adsorption module 45 of Production Example 1 at a water flow rate of 1 L / min, and the sodium concentration of the treated water was measured. The sodium concentration was measured by inductively coupled plasma-mass spectrometry (ICP-MS) for sample water. As a result, the sodium concentration of the treated water was 10 ng / L or less. Moreover, the water flow differential pressure at this time was 23 kPa.

Comparative Example 1
(Production example 2 of ion adsorption module)
The porous ion exchanger of Reference Example 12 was cut in a wet state to form a cylindrical porous ion exchanger having a diameter of 5 cm and a height of 5 cm, packed in a high-density polyethylene column having an inner diameter of 5 cm, and 1 mol / L nitric acid. After regeneration, it was thoroughly washed with ultrapure water to obtain a regenerated form, and an ion adsorption module was obtained.

(Water flow test 2)
A water flow test was conducted by the same method as in Example 1 except that the ion adsorption module obtained in Production Example 2 was used as the ion adsorption module. As a result, the sodium concentration of the treated water was 10 ng / L or less. Moreover, the water flow differential pressure at this time was 180 kPa.

  From Example 1 and Comparative Example 1, it was found that if the ion exchange module of the present invention is used, a treated water quality equal to or higher than that obtained when a conventional ion adsorption module is used can be obtained.

Example 2
Using each of the ion adsorption modules of Example 1, a module life test was performed. The water flow test was conducted in the same manner as the water flow test 1 except that the sodium concentration of the simulated contaminated pure water flowing through the ion adsorption module was 50 mg / L and the water flow velocity to the ion adsorption module was 0.2 L / min. The treated water was collected at regular intervals and the sodium concentration was measured. As a result, it was 153 minutes after the start of simulated contaminated pure water flow that the sodium concentration of treated water exceeded 1 mg / L.

Comparative Example 2
A life test of the module was performed in the same manner as in Example 2 except that the ion adsorption module of Comparative Example 1 was used. As a result, the treated water sodium concentration exceeded 1 mg / L at 57 minutes after the start of simulated contaminated pure water flow.

  From Example 2 and Comparative Example 2, when the ion adsorption module of the present invention is used, even when pure water is contaminated for some reason, stable and good outlet water quality can be maintained for a long time. It has been found that the replacement frequency of can be significantly reduced. Further, when the inflow ion load amount with respect to the total exchange capacity in the module when the treated water sodium concentration exceeds 1 mg / L is calculated, it becomes 87% in Example 2 and 79% in the comparative example, and the ion adsorption of the present invention. In the module, the utilization rate of ion exchange groups is high. In addition to the large exchange capacity per volume, it has been found that the high utilization rate enables a significantly long service life.

10a Ultrapure water production device 6, 45 Ion adsorption module 3 Ultrapure water transfer piping 4 Use point 20 Pretreatment device 21, 41 Raw water 30 Primary pure water production device 32, 42 Ion exchange device 50 Secondary pure water production Equipment 52, 43 Cartridge polisher 40 Water flow testing equipment 44 Sodium hydroxide aqueous solution injection equipment

Claims (5)

In the ultrapure water production equipment that transports ultrapure water and supplies it to the use point, in the middle of the pipe that transports the ultrapure water,
An organic porous body composed of a continuous skeleton phase and a continuous pore phase, and a large number of particles having a diameter of 4 to 40 μm fixed to the skeleton surface of the organic porous body or the skeleton surface of the organic porous body A composite structure with a large number of protrusions having a size of 4 to 40 μm, having an average pore diameter of 10 to 150 μm in a water-wet state, a total pore volume of 0.5 to 5 ml / g, and being in a water-wet state A module filled with a monolithic organic porous ion exchanger obtained by the following method for producing a monolithic organic porous ion exchanger having an ion exchange capacity per volume of 0.2 mg equivalent / ml or more, and the module The ultrapure water production apparatus characterized by further processing ultrapure water in
Method for producing monolithic organic porous ion exchanger:
Preparing a water-in-oil emulsion by stirring a mixture of an oil-soluble monomer free of ion exchange groups, a first crosslinking agent having at least two or more vinyl groups in one molecule, a surfactant and water; Step I for polymerizing a water-in-oil emulsion to obtain a monolithic organic porous intermediate having a continuous macropore structure with a total pore volume of 5 to 30 ml / g, vinyl monomer, at least two vinyls in one molecule Obtained in Step II and Step II to prepare a mixture comprising an organic solvent and a polymerization initiator that dissolves the second cross-linking agent having a group, the vinyl monomer and the second cross-linking agent, but does not dissolve the polymer formed by polymerization of the vinyl monomer. The resulting mixture is allowed to stand still and in the presence of the monolithic organic porous intermediate obtained in the step I, the step III, the monolith obtained in the step III IV introducing ion exchange groups into Jo organic porous material, a method of manufacturing a monolithic organic porous material for performing the following (1) to (5):
(1) The polymerization temperature in step III is at least 5 ° C. lower than the 10-hour half-life temperature of the polymerization initiator;
(2) The mol% of the second cross-linking agent used in step II is at least twice the mol% of the first cross-linking agent used in step I;
(3) The vinyl monomer used in Step II is a vinyl monomer having a structure different from that of the oil-soluble monomer used in Step I;
(4) The organic solvent used in step II is a polyether having a molecular weight of 200 or more;
(5) The concentration of the vinyl monomer used in Step II is 30% by weight or less in the mixture of Step II;
A method for producing a monolithic organic porous ion exchanger, wherein the step II or the step III is performed under conditions satisfying at least one of the above conditions.   2. The ultra-pure structure according to claim 1, wherein the organic porous body is a continuous macropore structure in which bubble-shaped macropores overlap each other, and the overlapping portion forms an opening having an average diameter of 30 to 150 μm in a wet state. Water production equipment.   The organic porous body is a three-dimensionally continuous skeleton having an average thickness of 1 to 60 μm in a water-wet state and a three-dimensionally continuous structure having an average diameter of 10 to 100 μm in a water-wet state between the skeletons. 2. The apparatus for producing ultrapure water according to claim 1, wherein the apparatus is a co-continuous structure composed of the formed pores.   The ultrapure water supplied to the module is a non-regenerative cartridge polisher filled with an ultraviolet oxidation device, an ultrafiltration device, and an ion exchanger after raw water is treated with a pretreatment device and a primary pure water production device. The ultrapure water production apparatus according to any one of claims 1 to 3, wherein the ultrapure water production apparatus is processed by a secondary pure water production apparatus comprising:   The apparatus for producing ultrapure water according to any one of claims 1 to 4, wherein the monolithic organic porous ion exchanger is a monolithic organic porous cation exchanger.