JP2006273930A - Particulate formed body carrying functional particle and its manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a formed body in which functional particles are carried on an easy-to-handle particulate polymer formed body without sacrificing functions inherent in the functional particles. <P>SOLUTION: A polymer solution in which the functional particles have been mixed and dispersed beforehand is sprayed into a gas to form particles. The particles formed are placed in a coagulation liquid. The polymer contained in the polymer solution is phase-separated in the coagulation liquid to form a formed body having numerous pores in it. The efficiency of contact of the functional particles carried in the formed body with an objective substance is improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a functional particle-supported molded article in which functional particles are supported on a polymer in a granular form that is easy to handle in adsorption and reaction processes without impairing the performance of the functional particles such as substance adsorption and substance reaction. This invention relates to a manufacturing method of the above and a molded product thereof.

  In recent years, with respect to substances that cause environmental problems, functional particles have been actively developed that decompose with a photocatalyst or metal catalyst that decomposes the substance or adsorb and recover with an adsorbent. However, the functional particles need to be supported on a material molded with another organic or inorganic substance depending on the application, and the functional particles need to effectively contact the target substance. Various studies have been made on the molded body and material, and the method of supporting the molded body on the molded body.

  As a method of supporting functional particles on a granular molded body, a method of granulating using a binder is common. However, simply granulating with a binder may result in the functional particles being coated on the binder, or the distance between the functional particles will be too narrow, increasing the diffusion resistance of the target substance into the molded body. There is a problem that the ability of functional particles cannot be expressed effectively.

  As a means for solving this problem, for example, a porous gel is formed by forming a wet gel in which functional particles are mixed in advance using a metal oxide or the like, and drying the gel to remove the internal solvent. Is disclosed (for example, see Patent Document 1).

  If this method is used, the diffusion resistance to the inside of the molded body will be reduced, and the functional particles inside the molded body that are exposed on the pore surface can be used effectively, and the space volume of the molded product can be made more efficient. However, since the wet gel needs to be subjected to a hydrophobic treatment or a supercritical treatment in order to obtain a porous carrier, there remains a problem that the process becomes complicated and costly. In addition, since the functional particles remain embedded in the higher order structure inside the molded body, there is still a problem that many functional particles that have high diffusion resistance and cannot be used effectively remain.

  Further, as a method for supporting the functional particles in the porous molded body, as for the fibrous molded body, the functional particles are mixed in advance in the molten thermoplastic resin, and further, A method is also disclosed in which an agent that can be extracted in the process is mixed, and after extrusion molding, the agent is extracted to provide pores in the fiber (for example, see Patent Document 2). However, this method can also effectively use the functional particles carried inside the molded body and appearing on the surface of the pores. However, an extraction step is necessary, and a step of treating the liquid generated in the extraction step In addition to the need for a new process, the original process becomes more complicated, and there are problems such as material loss and increased power consumption in the recovery process, and it is difficult to support functional particles on the surface of the pores. The problem was left.

  In addition, as a method of supporting functional particles on the surface of the polymer molded body, the “dipping method” in which the functional particles are dispersed in a solution-like binder and the polymer molded product is immersed in the binder solution, Similarly, the spray coating method, in which a binder solution in which functional particles are dispersed in a solution-like binder is sprayed and fixed onto a polymer molded product, uses a thermoplastic resin as a binder, and a premixed thermoplastic resin and functionality A method in which particles are dispersed on a polymer molded product and heat-pressed (for example, see Patent Document 3), or a method in which functionally imparted particles are directly heated and fixed to a nonwoven fabric made of thermoplastic polymer fibers without using a binder. (For example, refer to Patent Document 4 etc.). However, since functional particles are supported only on the surface of the molded body, the space volume of the molded product is effective. Cannot be used on a regular basis, and there are problems such as coating the surface of the functional particles with a binder and complication of the process. Manufacturing is possible in a simple process, and the space volume of the compact is efficiently used. However, there has been a strong demand for a method for supporting functional particles that fully express the function of the functional particles.

Japanese Patent Laying-Open No. 2005-52729 (Claims) JP-A-6-49705 (Claims) JP-A-10-99421 (Claims) JP-A-7-268767 (Claims)

  The object of the present invention is that the above-described conventional molding method is complicated and costly, and the functional particles that have not been able to fully exhibit their functions are used in the form of granular products. It is to provide a molding method to be carried on the substrate, and to provide a molded product thereof.

The inventors of the present invention have arrived at the present invention as a result of intensive studies in view of the above prior art.
That is, an object of the present invention is to form a polymer solution in which functional particles are dispersed, and after spraying the polymer solution into a gas and granulating it, the solution is poured into a coagulating liquid, and into the polymer solution in the coagulating liquid. This is a molding method for forming a large number of pores inside a molded body by phase-separating the contained polymer, and is achieved by a granular polymer molded body characterized in that functional particles are supported.

  A polymer solution in which functional particles are dispersed and mixed in advance is sprayed into a gas and granulated, and then charged into a coagulation liquid, and the polymer contained in the polymer solution is phase-separated in the coagulation liquid to form the inside of the compact By forming a large number of pores, the contact between the functional particles in the compact and the target substance can be dramatically improved, and the functions of the functional particles such as decomposition, reaction, and adsorption can be fully utilized. In this state, it is possible to provide a granular molded body that can be easily handled in the process.

Hereinafter, the present invention will be described in detail.
The present invention relates to industrial particles and industrial waste decomposition catalysts and adsorbents, functional particles represented by reaction catalysts and adsorbents in various manufacturing processes, without impairing the original functions of the functional particles. It is used for the purpose of improving the contact property of the functional particles occupying in the unit space by being supported on a granular polymer compact that is easy to handle.

  In the present invention, the functional particle refers not only to an adsorbed particle in which the particle itself adsorbs a specific substance or a plurality of substances to the functional particle, or is incorporated into the particle composition, or exchanged with the intraparticle composition, but also the particle itself. Means a catalyst particle that promotes decomposition, alteration or synthesis of the target substance, or a particle that reacts with itself, but the function of the particle is not particularly limited here. The functional particles may be in the form of powder, granules or porous granules, but those having a particle diameter of 0.01 to 500 μm are used. When the particle size is less than 0.01 μm, the particles are likely to aggregate and difficult to disperse in the polymer solution. On the other hand, when the particle diameter exceeds 500 μm, the ability of the functional particles is not sufficiently exhibited, and spraying into the gas becomes difficult.

  In addition, as polymers that can be wet-solidified, aramid resins, acrylic resins, vinyl alcohol resins, and cellulose resins are generally known. Here, a manufacturing method that is molded by the method described in this section Since the structure of the molded product obtained therefrom is important, the type of polymer is not particularly limited.

  Also, the shape of the pores in the formed body formed by solidification is not limited to a circular shape, for example, and can take various shapes. As for the size of the pores, the longest portion of the pores is preferably in the range of 0.1 to 150 μm, and among these, a form having pores of 20 to 100 μm is more preferable. In addition, these holes may be independent holes in the cross-sectional shape observed with an electron microscope of 1000 times or more, or may be continuous holes that are partially connected, but preferably It is preferable that the holes are partially connected or exist between the holes, and more preferably connected by fine holes.

  The outer shape of the granular molded body may be a true sphere, an elliptical sphere, depending on the concentration of the polymer solution, the distance between the spraying device (for example, spray nozzle) and the coagulation liquid level, the flow rate of the polymer solution / dehumidified pressure air, It can take the form of a distorted sphere or strand. About an external dimension, it is preferable that an average particle diameter is 0.05-2.0 mm. When the average particle size is less than 0.05 mm, the molded body easily flows out of the process together with the target substance in various processes using functional particles. For example, a filter with a fine mesh can be installed as one of the methods to suppress the outflow. However, if the filter is installed, the resistance to ventilation and water flow increases, so it is very disadvantageous in terms of processing capacity and equipment capacity, and is practical. is not. A method of recovering the molded body that has flowed out, for example, with a cyclone is also conceivable, but the addition of a recovery device for the molded body is not practical. On the other hand, when the average particle diameter exceeds 2.0 mm, the diffusion resistance for the target substance to reach the inside of the molded body increases, and thus the ability of the functional particles cannot be sufficiently exhibited. A more preferable average particle diameter in consideration of the above handling properties and ability expression of functional particles is 0.3 to 1.5 mm.

  These granular molded bodies having pores and supporting functional particles are obtained by mixing a mixture obtained by mixing and dispersing functional particles in a polymer solution in which a polymer is dissolved in a solvent. It is manufactured by extruding to a spraying device with a pressure of nitrogen or nitrogen, etc., spraying in a granular form from a spraying device into a gas, and then charging it into a coagulation liquid.

  In this production process, in the polymer solution in which the functional particles are mixed, 100 parts by weight of the polymer is dissolved in a solvent of 400 to 2500 parts by weight. Among these, the solvent amount of the polymer solution is 100 parts by weight of the polymer. On the other hand, the solvent amount is preferably 800 to 2300 parts by weight, and more preferably 1200 to 1900 parts by weight. Next, 10 to 9900 parts by weight of functional particles are dispersed and mixed in 100 parts by weight of the polymer in the polymer solution. The larger the amount of the functional particles in the molded body, the better, but the mixing amount is determined depending on the specific gravity, bulk, shape, and usage environment of the molded body.

  Next, the mixture in which the functional particles are mixed and dispersed is extruded to a spraying device with an extruder such as a gear pump or a pressure such as compressed air or nitrogen, sprayed in a granular form from the spraying device into a gas, and then charged into the coagulating liquid. It is manufactured by.

  The spraying device has a 1-fluid nozzle that discharges and sprays only the polymer solution to create a granular material, or a 2-fluid nozzle that forms auxiliary particles such as compressed air and nitrogen when discharging the polymer solution. A nozzle can be used. As the mixing of the auxiliary medium of the two-fluid nozzle and the polymer solution, either an internal mixing method of mixing inside the nozzle or an external mixing method of mixing outside the nozzle can be used. However, when a poor solvent is contained in the auxiliary medium, it is necessary to remove the poor solvent as necessary in order to prevent clogging in the nozzle.

  In the coagulation liquid, the polymer contained in the polymer solution undergoes phase separation, and large and small pores are formed in the molded body. The liquid composition of the coagulation liquid uses a poor solvent for the polymer used, and pores are formed by phase separation of the polymer and the solvent in the polymer solution. The type of the poor solvent can be arbitrarily selected depending on the type of polymer used. For example, N-methyl-2-pyrrolidone (hereinafter, abbreviated as NMP), which is an aramid polymer and one of its good solvents, may be used. If the functional particles are mixed with the polymer solution consisting of.), The target is obtained by coagulating with a poor solvent such as water or methyl alcohol or a solution containing 50% by weight or more of these solvents in the coagulation liquid. Production of a granular compact becomes possible. Further, when functional particles are mixed with a polymer solution composed of a polyacrylic polymer and dimethyl sulfoxide (hereinafter, may be abbreviated as DMSo) which is a good solvent for the polyacrylic polymer, water is added to the coagulation liquid. By solidifying with a poor solvent such as chlorobenzene, chloroform or methyl alcohol, or a solution containing 50% by weight or more of these solvents, it is possible to produce the desired granular molded body.

The granular compact with functional particles carried in the pores formed by solidification is effective even after drying and heat treatment, but if the target substance that expresses the performance of functional particles is a liquid, It is preferable to use it in a wet state without drying after coagulation. When drying is performed, gas is bitten into the pores of the molded body, so that sufficient effects may not be achieved unless deaeration is performed.
The target substance of the functional particles is not particularly limited as long as it is a gaseous or liquid fluid, the target substance dissolved in the fluid, or a solid that can be transported by the fluid.
Furthermore, since the functional particles in the molded body have high contact properties with the external fluid as described above, by selecting a polymer that can withstand the regeneration method inherent to the functional particles, it is the same as when functional particles are used alone. The ability can be replayed with the replay method.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

[Example 1]
A polymer solution comprising 3.9% by weight of meta-aramid polymer, 35.1% Mg-Al-Cl hydrotalcite adsorbent having an average particle size of 3 μm, and 61.0% by weight of NMP (functionality in the molded body) The amount of particles supported is 900 parts by weight with respect to 100 parts by weight of the polymer, and a polymer solution in which 1564 parts by weight of the solvent is used with respect to 100 parts by weight of the polymer. From the fluid external mixing type nozzle, it was sprayed into the gas at a polymer flow rate of 10 ml / min and a dehumidification pressure air pressure of 0.04 MPa, and then charged into a coagulation liquid tank. As the coagulation liquid, a solution of 99% by weight of water and 1% by weight of NMP was used at room temperature. The granular compact obtained by coagulation contained 90% by weight of the adsorbent with respect to the total weight of the compact and had voids (voids) inside (FIG. 1). Furthermore, when the surface of a void was expanded, it had a micro void with a smaller diameter (FIG. 2).

  From this granular molded body, a molded body having an average particle size of 0.5 to 1.4 mm is classified and taken out, and 1 g of the molded body with hydrotalcite weight is immersed in 500 mL of a solution having a phosphorous concentration of 0.9 mg / L. The mixture was stirred at 100 rpm using a propeller blade, and the phosphorus adsorption rate was measured. The result is shown in FIG.

  Here, the Mg—Al—Cl type hydrotalcite adsorbent is an adsorbent of phosphate ions, and the phosphorus concentration in FIG. 3 is determined by quantifying the phosphate ion concentration in 500 mL of the solution using the molybdenum blue method. This value is converted to phosphorus concentration.

[Example 2]
Use a polymer solution comprising 4.0% by weight of meta-aramid polymer, 33.8% Mg-Al-Cl type hydrotalcite adsorbent having an average particle size of 3 μm, and 62.3% by weight of NMP (in the molded body) Molding was performed in the same manner as in Example 1 except that the amount of the functional particles supported was 567 parts by weight with respect to 100 parts by weight of the polymer. The obtained granular compact contained 85% by weight of the total weight of the adsorbent and had voids inside.

  From this granular molded body, a molded body of 0.5 to 1.4 mm was classified and taken out, and 1 g of the molded body with hydrotalcite weight was immersed in 500 mL of a solution having a phosphorus concentration of 0.9 mg / L. 1 was used to measure the phosphorus adsorption rate. The result is shown in FIG.

[Example 3]
Except that the composition of the coagulation liquid was 70% by weight of water and 30% by weight of NMP, it was molded in the same manner as in Example 1 and the phosphorus adsorption rate was measured. The result is shown in FIG.

[Example 4]
Except that the temperature of the coagulation liquid was 50 ° C., molding was performed in the same manner as in Example 1, and the phosphorus adsorption rate was measured. The result is shown in FIG.

[Example 5]
The polymer solution sprayed into the gas was sprayed with a coagulating liquid of 100% by weight of water and then charged into the coagulating liquid tank, and then molded in the same manner as in Example 1, and the phosphorus adsorption rate was measured. The result is shown in FIG.

[Comparative Example 1]
A commercially available hydrotalcite granulated product having an average particle diameter of 2 mm containing 5% by weight of binder in the granulated product is made into a solution having a hydrotalcite weight of 1 g and a phosphorous concentration of 0.9 mg / L at 100 rpm using a propeller blade. The mixture was stirred and the phosphorus adsorption rate was measured. The result is shown in FIG.

  The present invention is a technology for supporting functional particles on a granular polymer molded body that is easy to handle in each step of decomposition, reaction, and adsorption without impairing the original characteristics of decomposition, reaction, and adsorption of functional particles. The present invention relates to a molded body that can effectively decompose, react, and recover substances contained in gas and liquid.

It is the photograph which image | photographed the cross section of the molded object of this invention with the electron microscope. It is an enlarged photograph figure of the void (hole) surface of FIG. It is a graph of the performance evaluation of the molded object obtained by this invention, and comparative evaluation.

Claims (9)

  In forming a polymer solution in which functional particles are dispersed, the polymer solution is sprayed into a gas and granulated, and then poured into a coagulation liquid, and the polymer contained in the polymer solution is phase-separated in the coagulation liquid. A method for producing a granular polymer molded article carrying functional particles, wherein a large number of pores are formed inside the molded article.   The production method according to claim 1, wherein the polymer solution is sprayed into the gas by a spray nozzle.   The manufacturing method of the polymer molded object of Claim 1 which sprays the polymer solution in which the solvent of 400-2500 weight part is used with respect to 100 weight part of polymers.   The method for producing a polymer molded body according to claim 1, wherein the amount of the functional particles supported in the molded body is 10 to 9900 parts by weight with respect to 100 parts by weight of the polymer.   The manufacturing method of Claim 1 which controls the void | hole formation conditions inside a molded object by controlling the poor solvent density | concentration in coagulation liquid.   The manufacturing method of Claim 1 which controls the hole formation conditions inside a molded object by controlling the temperature of coagulation liquid.   The production method according to claim 1, wherein the polymer solution sprayed in the gas is further solidified by spraying a coagulating solution and then coagulating the polymer solution in the coagulating solution.   A granular polymer molded article carrying functional particles, obtained by the production method according to claim 1.   The polymer molded body according to claim 8, wherein the molded body has a granular shape and an average particle diameter of 0.05 to 2.0 mm.

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