JPH11147983A - Molded body made of polymer adsorbent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molded article comprising a polymer adsorbent which has a sufficient organic substance adsorbing property and has a sufficient strength and can be used at a high flow rate. SOLUTION: A molded article composed of a polymer adsorbent and a porous binder, an adsorbent composed of the molded article, and an organic substance recovered from a fluid characterized by using the adsorbent,
How to remove.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded article obtained by binding a polymer-based adsorbent with a porous binder and a method for molding the same. The present invention also relates to a method for adsorbing and removing organic substances and the like from a fluid using the polymer adsorbent molded article.

[0002]

2. Description of the Related Art Recovering organic solvents such as hydrocarbons and halogenated hydrocarbons from contaminated gas is important from an economical point of view as well as from an environmental point of view.
In addition, collecting and removing organic substances present in water or an aqueous solution is an industrially important process, and is indispensable when recovering organic substances useful for medicine and the like from an aqueous solution such as a fermentation liquid.

[0003] Activated carbon has often been used as an adsorbent for recovering / removing organic solvents from contaminated gas. However, activated carbon to which an organic solvent has been adsorbed requires high-temperature steam during regeneration due to its strong adsorption power. This causes undesired results such as decomposition of chlorinated solvents. Further, when a ketone solvent such as methyl ethyl ketone or cyclohexanone is adsorbed, a serious problem such as ignition occurs due to its catalytic action. In some cases, an inorganic adsorbent such as zeolite is used, but in this case, too strong an adsorbing power and catalytic property pose a problem.

[0004] In order to avoid these problems, studies have been made on synthetic resin adsorbents having improved porosity and improved adsorbability. The synthetic resin-based adsorbent has characteristics such that the pore diameter can be freely changed, the adsorptive and desorbable properties can be controlled, and there is no catalytic activity. However, none of them has a small particle size and is practically unusable for removing / recovering substances from a fluid having a high flow rate, particularly a gas stream due to a problem of pressure loss. In addition, a method of molding an adsorbent such as zeolite or silica gel using a binder is disclosed, but none of these methods has low strength or sufficient adsorption performance.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a polymer adsorbent molded article having a sufficient organic substance adsorbing property, a sufficiently large particle size, and usable at a high flow rate. It is intended to provide a manufacturing method.

[0006]

That is, the gist of the present invention is as follows.
Molded body comprising a polymer-based adsorbent and a porous binder,
An adsorbent comprising the molded article, and a method for recovering and removing organic substances from a fluid, characterized by using the adsorbent. As a preferred embodiment of the present invention, the molded article of the present invention comprises (1) a polymer-based adsorbent, (2) a polymer binder that is dissolved in a water-miscible organic solvent and is insoluble in water, and
(3) It is obtained by dissolving a polymer binder, mixing an organic solvent which is water-miscible, molding, and then immersing the mixture in water to precipitate and make the binder porous.

[0007] More preferably, the above (1)-
In addition to (3), a crosslinking agent for the polymer binder is added, and the polymer binder is one or more selected from polyurethane, epoxy resin, and polyimide (more preferably, polyurethane and / or epoxy resin). ), The fluid is a gas, and the organic substance is a gaseous organic substance.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. As the polymer-based adsorbent of the present invention, those having a large specific surface area are preferable because of their high ability to adsorb organic substances. The polymer-based adsorbent can be produced by a known method, but the specific surface area per dry weight by the nitrogen adsorption BET method is 800 cm ² / g or more, preferably 1000 m ² / g or more, more preferably 1200 cm ² / g or more. Those having a high specific surface area are preferred. Such a polymer-based adsorbent having a high specific surface area can be obtained, for example, by appropriately selecting the production conditions by the method described in JP-A-8-155297. The adsorbent can be used for molding as it is, but can also be used after being pulverized by a jet mill or the like or mixed with a pulverized product.

The porous binder referred to in the present invention has a structure in which the surface of the polymer-based adsorbent is connected to the outside by continuous pores, and can bind the polymer-based adsorbent while having sufficient strength. Any material having this function may be used, but a material having a molecular weight that does not enter the pores of the polymer adsorbent is preferable. As the porous binder, various polyurethanes, epoxy resins,
Polyimide and the like, dissolved in a water-miscible organic solvent, and a water-insoluble polymer binder, a binder solution dissolved in a water-miscible organic solvent such as dimethylformamide (DMF) described below was immersed in water In this case, it is necessary to take a porous structure. This increases the practicality without impairing the speed adsorption performance of the molded body.

The crosslinking agent for the polymer binder can be appropriately selected depending on the polymer binder to be used. For example, in the case of using polyurethane, those having a reactive group cross-linking with polyurethane in the molecule, such as those having an active hydrogen group and those having an isocyanate group, can be used. Further, as a crosslinking agent for the epoxy resin, those having a reactive group cross-linking with an epoxy group in the molecule, such as a novolak resin and various amines, can be used.

As a solvent used at the time of molding, it is necessary to dissolve the binder and be water-miscible at the same time. For example, DMF, tetrahydrofuran, dioxane, acetone, water-soluble alcohol and the like can be used. To obtain the molded article of the present invention, first, a polymer-based adsorbent, a binder,
A binder cross-linking agent and a solvent are kneaded to form a uniform mixture.
The amount of the binder to be added is suitably 1% by weight or more and 30% by weight or less, preferably 5% by weight or more and 20% by weight or less based on the polymer adsorbent. The amount of the solvent added needs to be adjusted so that the mixture has a hardness suitable for extrusion molding, but is generally in the range of 50% by weight to 200% by weight based on the polymer adsorbent. In addition, powder of an inorganic salt such as calcium chloride may be added during kneading. In this case, at the time of water immersion in the post-treatment step, by extracting the inorganic salt added and kneaded here, pores are formed in the molded body, and the adsorption speed can be further improved.

The adsorbent mixture thus obtained is
It is molded by extruding into water with a vacuum extruder or the like. The size of the molded body is determined by the die diameter of the extruder, and preferably about 1 to 10 mm in diameter. By immersing the extrudate in water, a binder is precipitated and a porous structure is formed. It is necessary to perform immersion in water until the solvent such as DMF and the added inorganic salts are completely extracted, and it usually takes about 12 to 24 hours depending on the size of the extruded material. After the extrudate from which DMF etc. has been extracted is drained, it is cured / dried by holding it at a temperature equal to or higher than the reaction temperature of the cross-linking agent with an air dryer or the like, and then cut into appropriate lengths and finally molded. Can be obtained as a body.

[0013]

According to the present invention, the molded article made of the polymer adsorbent obtained by the present invention is excellent in speedy adsorption performance because the binder is made porous. Further, the use of a polymer-based adsorbent has advantages such as no catalytic activity for organic substances. The molded body comprising the polymer-based adsorbent obtained in the present invention is used for removing / recovering organic substances and the like from a fast fluid stream, particularly a gas stream. Organic substances include methyl ethyl ketone, cyclohexanone, styrene, toluene,
There are volatile organic compounds such as ethylene dichloride. It is also used in the field of high flow rate conditions in liquid processing and in the field of liquid processing involving colloidal substances. In addition, when used in an upflow, there is an advantage that a high flow rate is possible due to a large particle diameter.

[0014]

The present invention will be described more specifically below with reference to typical examples and comparative examples. In addition, the porous beads which are the polymer-based adsorbent raw materials used below were all obtained by the following method.

Reference Example Production of polymer-based adsorbent raw material (100 g of porous beads)
(Production) (Production of crosslinked copolymer beads) 97.1 g of styrene, 5.5 g of divinylbenzene (purity: 56.5%, others: ethylvinylbenzene), dibenzoyl peroxide (purity: 7)
5%, water is 1.37 g, and 25.6 g of polystyrene (average molecular weight: 45,000) are mixed, added to 667 ml of deionized water containing 0.64 g of polyvinyl alcohol and 0.04 g of methylene blue, and stirred to remove oil droplets. Formed. After the temperature was raised to 80 ° C., polymerization was carried out at 80 ° C. for 8 hours to obtain crosslinked polystyrene particles. The obtained particles were washed with water and toluene, and then toluene was distilled off and further dried.

(Haloalkylation of crosslinked copolymer beads)
40 g of the dried crosslinked polystyrene particles were suspended in chloromethyl methyl ether for 1 hour. Next, 20 g of zinc chloride was added, and the mixture was further stirred for 1 hour, heated to 50 ° C., and kept for 8 hours. The reactor was cooled, the reaction was stopped by adding water, and after washing with water, the chloromethylated crosslinked copolymer was dried.

(Production of porous beads) 50 g of chloromethylated crosslinked copolymer beads were swollen in 350 ml of ethylene dichloride for 1 hour. Thereto, 15 g of ferric chloride was added, and the mixture was further stirred for 1 hour. After the temperature was raised to 80 ° C., the temperature was further maintained for 8 hours and then cooled to stop the reaction. After distilling off ethylene dichloride, the porous beads of the post-crosslinked copolymer were dried to obtain a product. The specific surface area of the obtained porous beads per dry weight by a nitrogen adsorption BET method (all the specific surface areas described below were measured by this method) was 156.
It was 0 m ² / g.

Example 1 Polymer adsorbent 50 g, polyurethane (trade name: MP865-PS; manufactured by Dainippon Ink: concentration 30 to
40% DMF solution) 16.8g, polyurethane crosslinking agent NY730S
After mixing 1.24 g (manufactured by Mitsubishi Chemical) and 64.1 g of DMF in a mortar until uniform, the mixture was extruded with a hydraulic extruder having a die diameter of 5 mm, and the extruded product was placed in a beaker containing deionized water. After replacing the demineralized water several times, it was immersed in demineralized water overnight. After the extrudate was drained, it was dried at 100 ° C. for 8 hours with a blow dryer to obtain a molded product. The specific surface area of the molded body is 1061 m ² / g
Met. After cutting to a length of about 5mm, Autograph AGS-50
The crushing strength measured with a load of 5 mm / min using OB (manufactured by Shimadzu Corporation) was 6.6 kg / piece. 20 g of the molded product cut into a length of about 5 mm was packed in a column having an inner diameter of 28 mm, and methyl ethyl ketone (MEK) vapor having a concentration of 12800 ppm diluted with nitrogen was passed through a 30 ° C. column oven at a flow rate of 2.0 L / min. 70 after ventilation
No MEK leaks were seen until minute.

Example 2 Polymeric adsorbent of Example 1
40 g, polyurethane (MU735; manufactured by Mitsubishi Chemical: about 30% concentration)
13.6g, polyurethane crosslinking agent NY730S 1.0
g, DMF60g, Calcium chloride (for moisture measurement) 10.0g
After mixing until uniform in a mortar, die diameter 4.8
The product was extruded with a commercially available meat chopper (mm) and the extruded product was placed in a beaker containing deionized water. After replacing the demineralized water several times, it was immersed in demineralized water overnight. After the extrudate was drained, it was dried at 100 ° C. for 8 hours with a blow dryer to obtain a molded product. After cutting to a length of about 5mm, crush strength
It was 1.0 kg / piece when measured at a load of 0.2 kg / s using LLON (manufactured by John Chatillon and Sons New York). 20 g of the molded product cut into a length of about 5 mm was packed in a column having an inner diameter of 28 mm, and MEK vapor having a concentration of 9970 ppm diluted with nitrogen was passed through a 30 ° C. column oven at a flow rate of 2.0 L / min. No MEK leak was observed up to 130 minutes after ventilation. 30mm inside diameter
And air was bubbled at room temperature. Linear velocity 0.10m /
The differential pressure between the column inlet and outlet at sec is approximately 30
mmH was ₂ O / m.

Example 3 Polymeric adsorbent of Example 1
50 g, polyurethane (MP865-PS; manufactured by Dainippon Ink) 16.7 g, polyurethane curing agent NY730S (manufactured by Mitsubishi Chemical)
1.25 g, 84.2 g of DMF and 13.0 g of calcium chloride (for moisture measurement) previously ground in a mortar were mixed in a mortar until uniform, and then extruded with a hydraulic extruder having a die diameter of 5 mm. Received in a beaker. After the demineralized water was replaced several times, it was immersed in demineralized water overnight. On the way, the mixture was filtered several times to replace the demineralized water, and DMF and calcium chloride were extracted. After draining the extrudate, use an air dryer to
Drying was performed at 8 ° C. for 8 hours to obtain a molded body. The specific surface area of the molded body is
It was 1249 m ² / g. After cutting to a length of about 5 mm, the autograph
The crushing strength measured with AGS-500B in the same manner as in Example 1 was 2.7 kg / piece. 20g of molded body cut into length of about 5mm
Is packed in a 28 mm ID column, and 13200 ppm MEK vapor diluted with nitrogen is flowed at 2.0 L in a 30 ° C column oven.
aerated at / min. No leak of MEK was observed until 120 minutes after ventilation.

Example 4 Polymeric adsorbent of Example 1
35 g, and an average particle size of 3.8 when crushed with a jet mill.
μm (particle size is measured by laser diffraction scattering type particle size distribution analyzer SK RAS
15 g of ER MICRON SIZERLMS-24 (a value measured by Seishin Enterprise), 16.7 g of polyurethane (MP865-PS; manufactured by Dainippon Ink), 1.23 g of polyurethane crosslinking agent NY730S (manufactured by Mitsubishi Chemical), and 53.0 g of DMF After mixing until uniform, extrude with a hydraulic extruder with a die diameter of 5 mm,
The extrudate was placed in a beaker containing demineralized water. After the demineralized water was replaced several times, it was immersed in demineralized water overnight. After the extrudate was drained, it was dried at 100 ° C. for 8 hours with a blow dryer to obtain a molded product. After cutting to a length of about 5 mm, the autograph AGS-50
The crushing strength measured at 0B in the same manner as in Example 1 was 12.9.
kg / piece. 20 g of the molded product cut into a length of about 5 mm was packed in a column having an inner diameter of 28 mm, and MEK vapor having a concentration of 13200 ppm diluted with nitrogen was passed through a 30 ° C. column oven at a flow rate of 2.0 L / min. No leak of MEK was observed until 60 minutes after ventilation.

Example 5 Polymeric adsorbent of Example 1
40 g, 23% -epoxy resin (1010; Yuka Shell Epoxy) / DMF solution 20.0 g, epoxy crosslinker (EK-W; Yuka Shell Epoxy) 0.09 g, DMF 50.0 g are homogenized in a mortar. Then, the mixture was extruded with a commercially available meat chopper having a die diameter of 4.8 mm, and the extruded product was placed in a beaker containing deionized water. After replacing the demineralized water several times, it was immersed in demineralized water overnight. After the extruded product was drained, it was dried at 150 ° C. for 3 hours with a blow dryer to obtain a molded product. Length about 5mm
After cutting into pieces, crushing strength (CHATILLON; JOHN
CHATILLON AND SONS NEW YORK, same conditions as in Example 2)
Was 1.2 kg / piece. 20 g of the molded product cut into a length of about 5 mm was packed in a column having an inner diameter of 28 mm, and MEK vapor having a concentration of 12700 ppm diluted with nitrogen was passed through a 30 ° C. column oven at a flow rate of 2.0 L / min. No leak of MEK was observed until 50 minutes after ventilation.

Example 6 Polymeric adsorbent of Example 1
40.1g, Polyimide (Mitsubishi Chemical) / DMF solution (25%)
After 16.1 g and 50.2 g of DMF were mixed in a mortar until uniform, the mixture was extruded with a commercially available meat chopper having a die diameter of 4.8 mm, and the extruded product was placed in a beaker containing demineralized water. After replacing the demineralized water several times, it was immersed in demineralized water overnight.
After the extruded product was drained, it was dried at 150 ° C. for 3 hours with a blow dryer to obtain a molded product. After cutting to a length of about 5 mm, crushing strength (CHATILLON; JOHN CHATILLON AND SONS
NewYORK manufactured under the same conditions as in Example 2).
kg / piece. Inner diameter of 20g molded product cut to about 5mm in length
A 28 mm column was filled, and MEK vapor having a concentration of 10500 ppm diluted with nitrogen in a 30 ° C. column oven was passed through at a flow rate of 2.0 L / min. No leak of MEK was observed until 120 minutes after ventilation.

Comparative Example 1 (When the binder is not porous) The polymer adsorbent used in Example 1 was pulverized with a jet mill to obtain a pulverized product having an average particle diameter of 7.1 μm. The particle size is a value measured by a laser diffraction scattering type particle size distribution analyzer SK RASER MICRONSIZER LMS-24 (manufactured by Seishin Enterprise). Adsorbent fine powder 700g, 4.
6% methyl cellulose (Metroze SM-100; manufactured by Shin-Etsu Chemical)
After kneading 1260 g of the aqueous solution with a kneader until uniform,
It was extruded with a vacuum extruder having a die diameter of 5 mm. The obtained extrudate was air-dried for 48 hours, and then dried at 120 ° C. for 12 hours with a blow dryer to obtain a molded product. Molded body 20 cut to a length of about 5 mm
g in a 28 mm ID column, and MEK vapor at a concentration of 12800 ppm diluted with nitrogen in a 30 ° C. column oven at a flow rate of 2.0 L / m2.
vented in. MEK leaked 2 minutes after venting.

Comparative Example 2 (In the case of using only a synthetic adsorbent without using a binder)
Synthetic adsorbent SP85 consisting of divinylbenzene copolymer
0 (manufactured by Mitsubishi Chemical Corporation) (average particle diameter: 400 μm) was packed in a column having an inner diameter of 30 mm, and air was ventilated at room temperature. Linear velocity 0.10m / s
The pressure difference between the column inlet and outlet at is approximately 1000mm in 1m
It was H ₂ O / m.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09J 175/04 C09J 175/04

Claims (8)

[Claims] 1. A molded article comprising a polymer adsorbent and a porous binder. 2. A polymer adsorbent, (2) a polymer binder soluble in a water-miscible organic solvent and insoluble in water, and (3) a polymer binder dissolved in a water-soluble organic solvent. The molded article according to claim 1, wherein the molded article is obtained by mixing and shaping a mixed organic solvent, and then immersing the mixture in water to precipitate and make the binder porous. 3. A polymer adsorbent, (2) a polymer binder that is soluble in a water-miscible organic solvent and is insoluble in water, and (3) a polymer binder that dissolves in a water-miscible solvent. The molded article according to claim 1, which is obtained by mixing and shaping an organic solvent as described above and (4) a crosslinking agent for the polymer binder, and then immersing the mixture in water to precipitate and make the binder porous. 4. The molded article according to claim 2, wherein the polymer binder is at least one selected from polyurethane, epoxy resin and polyimide. 5. The molded article according to claim 1, wherein the polymer binder is a polyurethane and / or an epoxy resin. 6. An adsorbent comprising the molded article according to claim 1. 7. A method for recovering and removing organic matter from a fluid, comprising using the adsorbent according to claim 6. 8. The method according to claim 7, wherein the fluid is a gas and the organic matter is a gaseous organic matter.