JP2021098177A - Adsorbent and method for producing the same - Google Patents

Abstract

To provide a new adsorbent which is excellent in odor component removal performance, and a method for producing the same.SOLUTION: An adsorbent contains a base material, a porous adsorbent containing a porous carrier and a hydroxyl group-containing water-soluble polymer, and a binder. The porous adsorbent is obtained by attaching the hydroxyl group-containing water-soluble polymer to the porous carrier surface, an amount of a hydroxyl group contained in the hydroxyl group-containing water-soluble polymer is 1.0-3.8 atm%, a pH of the adsorbent is 5.4-9.5, and a specific surface area of the adsorbent is 300 m2/g or more.SELECTED DRAWING: None

Description

The present invention relates to an adsorbent and a method for producing the same.

Various odor components are present in the interior of an automobile, the interior of a house, and the like, and when the concentration of these odor components is high, discomfort may be caused. Activated carbon is generally used to remove such an odorous component, and various adsorbents using activated carbon have been developed.

For example, Patent Document 1 discloses an air filter filter medium having excellent deodorizing and antifungal properties as an air filter filter medium used in a household air purifier or an automobile air conditioner. This air filter filter medium is formed through a step of impregnating a non-woven fabric with a dispersion liquid containing activated carbon powder, an antibacterial antifungal agent, and a binder. In order to achieve both deodorizing property and antifungal property, the dispersion liquid liquid is used. In order to stabilize the properties, a cellulose derivative is added as a dispersant to the dispersion liquid containing the activated carbon powder, the antibacterial fungicide and the binder (paragraphs 0010, 0023, 0033, 0055).

However, since activated carbon is mainly physically adsorbed by pore distribution, it can adsorb a wide variety of odorous components to some extent, but if a certain amount of odorous components are adsorbed, the removal performance is significantly reduced, so the adsorption power for odorous components is high. Not enough. Further, activated carbon has a problem that once adsorbed odorous components are easily desorbed depending on the ambient temperature and the concentration of the odorous components.

As an adsorbent (deodorant) capable of removing a complex odor containing a plurality of odor components, Patent Document 2 describes that activated carbon is a first deodorant in which a phosphoric acid and / or a water-soluble copper compound is impregnated, and activated carbon is used. A deodorant comprising a second deodorant impregnated with a cyclic saturated amine compound and a basic compound and a third deodorant impregnated with a metal phthalocyanine complex on a cellulose granulated body is disclosed (claim 1). ). The first deodorant mainly deodorizes ammonia, the second deodorant mainly deodorizes acetaldehyde, and the third deodorant mainly deodorizes sulfur-based components (paragraph 0034). ~ 0036).

However, since three kinds of deodorants are used to remove the complex odor, it cannot be said that the removal is efficient.

Japanese Unexamined Patent Publication No. 2016-174997 JP-A-2017-64048

As described above, it is desired to develop a new adsorbent having excellent removal performance of a wide variety of odor components and a new adsorbent having excellent removal performance of a composite odor containing a plurality of odor components.
An object of the present invention is to provide a novel adsorbent having excellent odor component removing performance and a method for producing the same.

The present inventors have made diligent research in order to solve the above problems, and have arrived at the present invention. The present invention has, for example, the following aspects.

<Aspect 1>
An adsorbent containing a base material, a porous carrier, a porous adsorbent containing a hydroxyl group-containing water-soluble polymer, and a binder. The porous adsorbent is a hydroxyl group-containing water-soluble material on the surface of the porous carrier. The amount of hydroxyl groups contained in the hydroxyl group-containing water-soluble polymer is 1.0 to 3.8 atm%, and the pH of the adsorbent is 5.4 to 9.5. Yes, the adsorbent has a specific surface area of 300 m ² / g or more.

<Aspect 2>
The porous adsorbent is obtained by adding the hydroxyl group-containing water-soluble polymer to the dispersion liquid of the porous carrier that does not contain the binder, and bringing the hydroxyl group-containing water-soluble polymer into contact with the porous carrier. The adsorbent according to aspect 1, which is formed by.

<Aspect 3>
The amount of hydroxyl groups contained in the above-mentioned hydroxyl group-containing water-soluble polymer may be 1.2 to 3.8 atm%, or may be 1.2 to 2.4 atm%, according to Aspect 1 or 2. Adsorbent.

<Aspect 4>
The adsorbent according to any one of aspects 1 to 3, wherein the pH of the adsorbent may be 5.5 to 9.5 or 5.5 to 9.3.

<Aspect 5>
The adsorbent according to any one of aspects 1 to 4, wherein the specific surface area of the adsorbent ^{may be 310 m 2 / g or more.}

<Aspect 6>
The adsorbent according to any one of aspects 1 to 5, wherein the specific surface area of the adsorbent ^{may be 700 m 2 / g or less.}

<Aspect 7>
The adsorbent according to any one of aspects 1 to 6, wherein the hydroxyl group-containing water-soluble polymer is a cellulosic resin.

<Aspect 8>
The adsorbent according to any one of aspects 1 to 7, wherein the hydroxyl group-containing water-soluble polymer is carboxymethyl cellulose or a salt thereof.

<Aspect 9>
The adsorbent according to any one of aspects 1 to 8, wherein the porous adsorbent contains at least a sodium salt of carboxymethyl cellulose as the hydroxyl group-containing water-soluble polymer.

<Aspect 10>
The adsorbent according to any one of aspects 1 to 9, wherein the porous carrier is activated carbon.

<Aspect 11>
The adsorbent according to any one of aspects 1 to 10, wherein the base material is a sheet-shaped breathable base material.

<Aspect 12>
The method for producing an adsorbent according to any one of aspects 1 to 11.
To prepare a dispersion of the above porous carrier,
By adding the hydroxyl group-containing water-soluble polymer to the dispersion and bringing the hydroxyl group-containing water-soluble polymer into contact with the porous carrier, the hydroxyl group-containing water-soluble polymer is brought to the surface of the porous carrier. To obtain the porous adsorbent that is attached,
To prepare a slurry containing the porous adsorbent and the binder,
Bringing the substrate into contact with the slurry and drying the substrate in contact with the slurry.
A method for producing an adsorbent containing.

According to the present invention, a novel adsorbent having excellent odor component removing performance and a method for producing the same are provided.

The image figure which shows a part of the cross section of the porous adsorbent provided in the adsorbent which concerns on this embodiment. FIG. 5 is an image diagram showing a state in which the pores of the porous adsorbent included in the adsorbent according to the present embodiment are viewed from the front. An enlarged photograph showing the surface of the adsorbent according to the present embodiment. The graph which shows an example of the influence which the amount of OH groups has on the removal performance of a complex odor. The graph which shows an example of the influence which the amount of OH groups has on the removal performance of trimethylamine. The graph which shows an example of the influence which the amount of OH groups has on the removal performance of acetic acid. The graph which shows an example of the influence which the amount of OH groups has on the removal performance of toluene. The graph which shows an example of the influence which the pH of an adsorbent has on the removal performance of a complex odor. The graph which shows an example of the influence which the pH of an adsorbent has on the removal performance of trimethylamine. The graph which shows an example of the influence which the pH of an adsorbent has on the removal performance of acetic acid. The graph which shows an example of the influence which the pH of an adsorbent has on the removal performance of toluene. The graph which shows an example of the influence which the specific surface area of an adsorbent has on the removal performance of a composite odor. The graph which shows an example of the influence which the specific surface area of an adsorbent has on the removal performance of trimethylamine. The graph which shows an example of the influence which the specific surface area of an adsorbent has on the removal performance of acetic acid. The graph which shows an example of the influence which the specific surface area of an adsorbent has on the removal performance of toluene.

Hereinafter, embodiments of the present invention will be described.
The adsorbent according to the embodiment of the present invention (hereinafter, referred to as "the present embodiment") includes a base material, a porous adsorbent, and a binder, and the porous adsorbent is a base material via a binder. Is bound to.

The porous adsorbent included in the adsorbent according to the present embodiment contains a porous carrier and a hydroxyl group-containing water-soluble polymer, and has a structure in which the hydroxyl group-containing water-soluble polymer is adhered to the surface of the porous carrier. FIG. 1A is an image diagram showing a part of a cross section of the porous adsorbent 10, and shows a state in which a hydroxyl group-containing water-soluble polymer 2 is attached to the surface of the porous carrier 1. The inside of the broken line A represents a plurality of odor components including the odor component a1. As can be seen from FIG. 1A, the surface of the porous carrier 1 is adhered with a water-soluble polymer 2 having a hydroxyl group (hereinafter, also referred to as “OH group”), whereby the porous carrier 1 includes the surface inside the pores 3. A hydrogen bonding force is imparted to the surface of the quality adsorbent 10. As a result, on the surface of the porous adsorbent 10 having a large surface area, an intermolecular force is formed with the functional groups of the plurality of odor components, and the plurality of odor components can be efficiently trapped. Further, since an intermolecular force is formed between the odor component and the odor component, the desorption of the once adsorbed odor component is suppressed.

FIG. 1B is an image diagram showing a state in which the pores 3 of the porous adsorbent 10 are viewed from the front. By adhering the hydroxyl group-containing water-soluble polymer 2 to the surface of the pores 3, a hydrogen bonding force is imparted to the surface of the pores 3, and the odor component a1 is trapped in the pores 3. In the pores 3, the odor component a1 receives the hydrogen bonding force of the OH group from all sides and is trapped, so that the ability to suppress the desorption of the odor component once adsorbed is even higher.

By adhering the hydroxyl group-containing water-soluble polymer to the surface of the porous carrier in this way, the hydrogen bonding force of the hydroxyl group-containing water-soluble polymer due to the OH group and the physical adsorption force of the porous carrier having a high specific surface area can be obtained. Due to the synergistic effect of, a wide variety of odorous components and complex odors can be trapped and removed, and the odorous components once adsorbed are also suppressed from being desorbed, so that the odorous components are efficiently removed. can do. On the other hand, the third deodorant disclosed in Patent Document 2 is a deodorant based on a cellulose compound (corresponding to a hydroxyl group-containing water-soluble polymer), and has an odor due to a hydrogen bond reaction in the pores. It is difficult to efficiently remove the odorous component because the effect of trapping the component cannot be achieved.

In the present specification, the above-mentioned attachment means a state in which a hydroxyl group-containing water-soluble polymer is attached to the surface of a porous carrier.

The hydroxyl group-containing water-soluble polymer is attached to the surface of the porous carrier in a state in which the hydroxyl group-containing water-soluble polymer is added to the dispersion liquid of the porous carrier before the porous carrier is mixed with the binder, and the binder is absent. It is formed by contacting a hydroxyl group-containing water-soluble polymer with a porous carrier. For example, in Patent Document 1, in the production of an air filter, activated carbon powder (corresponding to a porous carrier), an antibacterial antifungal agent, a binder and carboxymethyl cellulose (corresponding to a hydroxyl group-containing water-soluble polymer) are dispersed in water. The treated liquid obtained by mixing and stirring is impregnated into the non-woven fabric by the size press treatment (paragraph 0033), but when the activated carbon powder and carboxymethyl cellulose are mixed in the presence of the binder in this way, the binder becomes the activated carbon powder. The binding inhibits the binding between the activated carbon powder and carboxymethyl cellulose, and the carboxymethyl cellulose does not adhere to the surface of the activated carbon powder.

As a result of further diligent research by the present inventors, the synergistic effect of the hydrogen bonding force of the OH group of the hydroxyl group-containing water-soluble polymer and the physical adsorption force of the porous carrier is further enhanced, and the removal performance for odorous components is further enhanced. In order to improve, (i) the amount of OH groups contained in the hydroxyl group-containing water-soluble polymer and / or (ii) the pH of the adsorbent and / or (iii) the specific surface area of the adsorbent are important. It was found to be a factor.

The present inventors have a synergistic effect between the hydrogen bonding force of the OH group of the above-mentioned hydroxyl group-containing water-soluble polymer and the physical adsorption force of the porous carrier, and the above-mentioned synergistic effect can have a significant effect. In finding the factors (i) to (iii), three components of trimethylamine (alkaline), acetic acid (acidic), and toluene (non-polar) were selected as substitute components as a plurality of odor components contained in the complex odor. By studying and evaluating the removal performance of odorous components for each, the removal performance for complex odors was found, and the present invention was developed.

In order to obtain an adsorbent having excellent complex odor removing performance, it is preferable to adjust the amount of hydroxyl groups, the pH of the adsorbent, and the specific surface area of the adsorbent as follows.
(i) Amount of hydroxyl groups (OH groups) In order to obtain an adsorbent with excellent complex odor removal performance, the amount of OH groups contained in the hydroxy group-containing water-soluble polymer adhering to the surface of the porous carrier is , 1.0 to 3.8 atm%, or 1.2 to 3.8 atm%, or 1.2 to 2.4 atm%. If the amount of OH groups is small, the hydrogen bonding force decreases. On the other hand, if the amount of OH groups is large, the surface of the pores becomes rich in OH groups and an effective reaction field cannot be obtained.
The amount of OH groups contained in the hydroxyl group-containing water-soluble polymer is measured by the method described in [Example] described later.

Here, the effect of the amount of OH groups on the removal performance of odorous components is that when the complex odor is divided into three components, trimethylamine (alkaline), acetic acid (acidic), and toluene (non-polar), toluene (non-polar) is used. ), It was found that it has a greater effect on trimethylamine (alkaline) and acetic acid (acidic) and is more effective.

(Ii) pH of adsorbent
In order to obtain an adsorbent having excellent complex odor removing performance, the pH of the adsorbent may be 5.4 to 9.5, or may be 5.5 to 9.5, or 5.5. It may be ~ 9.3. When the pH of the adsorbent is low, the hydroxy group-containing water-soluble polymer is hydrolyzed and the removal performance is deteriorated. On the other hand, when the pH of the adsorbent is high, the hydroxyl group-containing water-soluble polymer is decomposed by an oxidation reaction, and the removal performance is deteriorated.
Here, the pH of the adsorbent is measured by the method described in [Example] described later.

The effect of the pH of the adsorbent on the removal performance of odorous components is that when the complex odor is divided into three components, trimethylamine (alkaline), acetic acid (acidic), and toluene (non-polar), toluene (non-polar) It was found to be more effective on trimethylamine (alkaline) and acetic acid (acidic) than on trimethylamine.

(Iii) Specific Surface Area of Adsorbent In order to obtain an adsorbent having excellent removal performance of complex odor, the specific surface area of the adsorbent may be 300 m ² / g or more, or 310 m ² / g or more. .. If the specific surface area of the adsorbent is low, the removal performance will deteriorate. On the other hand, the upper limit of the specific surface area of the adsorbent is not particularly limited and can be set as appropriate. For example, the specific surface area of the adsorbent ^{may be 700 m 2} / g or less. Here, the specific surface area of the adsorbent is measured by the method described in [Example] described later.

The effect of the specific surface area of the adsorbent on the removal performance of odorous components is that when the composite odor is divided into three components, trimethylamine (alkaline), acetic acid (acidic), and toluene (non-polar), acetic acid (acidic). It has been found to be more effective on trimethylamine (alkaline) and toluene (non-polar) than on trimethylamine.

Next, the porous adsorbent, the base material, and the binder constituting the adsorbent according to the present embodiment will be specifically described.
<Porous adsorbent>
As described above, the porous adsorbent is an adsorbent obtained by adsorbing a hydroxyl group-containing water-soluble polymer on the surface of the porous carrier. As the porous adsorbent, one kind or a plurality of kinds can be used.

(Hydroxy group-containing water-soluble polymer)
The hydroxyl group-containing water-soluble polymer may be any one that can impart hydrogen bonding force to the surface of the porous carrier by adhering to the surface of the porous carrier (including the surface of the pores). Specific examples thereof include cellulosic resins. Examples of the cellulosic resin include carboxymethyl cellulose (CMC) or a salt thereof, hydroxyethyl cellulose (HEC) or a salt thereof, and the like. In one form, carboxymethyl cellulose (CMC) or a salt thereof having a higher water solubility is preferable, and a sodium salt of carboxymethyl cellulose (CMC · Na) is more preferable.

The weight average molecular weight of the hydroxyl group-containing water-soluble polymer may be 2 million or less, or 500,000 or less, from the viewpoint of the removal performance of the complex odor. The lower limit of the weight average molecular weight is not particularly limited and can be set as appropriate, and may be, for example, 250,000 or more. As used herein, the weight average molecular weight is measured by the Gel Permeation Chromatography (GPC) method.

(Porous carrier)
As the porous carrier, any carrier having a large number of pores can be used. For example, as the porous carrier, either an inorganic porous carrier or an organic porous carrier can be used.

Specific examples of the inorganic porous carrier include activated carbon, sepiolite, parigolskite, zeolite, activated carbon fiber, activated alumina, sepiolite mixed paper, silica gel, activated clay, permiculite, and diatomaceous earth. In addition, examples of the organic porous carrier include pulp, fiber, and polymer porous carrier. In one form, activated carbon is preferably used.

The shape of the porous carrier is not particularly limited as long as it can be attached with a hydroxyl group-containing water-soluble polymer. For example, granular, powdery, or fibrous porous carriers can be used. When the porous carrier is coated on the sheet-like breathable substrate, the porous carrier is preferably used in the form of a slurry. Therefore, in this case, a crushed and / or crushed porous carrier may be selected. .. Further, the type and shape of the porous carrier to be used can be selected according to the type of the odorous component to be removed or the place where the adsorbent is installed.

The specific surface area of the porous carrier may be ^{1000 m 2} / g or more, or 1100 m ² / g or more, from the viewpoint of the removal performance of the composite odor. The upper limit value is not particularly limited and can be set as appropriate, and may be, for example, 1600 m ² / g or less. In the present specification, the specific surface area of the porous carrier is _{derived by the N 2} adsorption BET multipoint method.

The particle size (median diameter: D50) of the porous carrier is preferably small, for example, for slurry formation, and may be, for example, 150 μm or less, 50 μm or less, or 25 μm or less. On the other hand, the lower limit of the particle size (median diameter: D50) of the porous carrier is not particularly limited and can be appropriately set, and may be, for example, 5 μm or more.

<Base material>
As the base material, it is preferable that the slurry containing the porous adsorbent can penetrate into the base material in the manufacturing process, and in one form, it is preferably a breathable base material. The shape of the base material is not particularly limited, and can be appropriately selected depending on the intended purpose, such as a sheet shape.

Specific examples of the sheet-like breathable base material include foamed resin, net-like resin, porous resin film, knitted fabric, woven fabric, non-woven fabric, paper, and inorganic fiber. The materials include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyurethane, nylon, polyvinyl chloride, polyvinylidene chloride, fluororesin, vinylon, aramid, polyacrylic polymer, cellol acetate, and pro. Synthetic fibers such as mixed; semi-synthetic fibers; recycled fibers such as rayon; natural fibers such as cotton, linen and silk: or inorganic fibers can be used. Further, the sheet-like breathable base material may be a woven fabric woven with a thin metal wire. From the viewpoint of resilience and compressive elasticity in the drying step in the manufacturing method described later, a sheet-like breathable base material such as a non-woven fabric made of a material containing polyethylene terephthalate can be preferably used.
FIG. 2 is an enlarged photograph showing the surface of the adsorbent according to the embodiment of the present invention. A porous adsorbent is fixed with a binder to a sheet-like breathable base material made of a fibrous material.

In this embodiment, the basis weight of the substrate may be, for example, 10 to 400 g / ^{m 2,} or may be a 30~300g / ^{m 2,} or may be 50 to 200 g / ^{m 2.} As used in the present specification, the "base weight of the base material" means the mass of the base material per ^{1 m 2.}

<Binder>
As the binder, any binder capable of binding the porous adsorbent and the base material, for example, an organic binder such as a polymer material can be used.

Examples of the organic binder include emulsion-based organic binders, and in particular, acrylic resins such as acrylic resins, acrylic-styrene resins, acrylic-silicon resins, acrylic-urethane resins, vinyl acetate-acrylic resins, and polysiloxane-acrylic resins. Emulsions and latex-based emulsions such as butadiene resin can be used. In one form, as the binder, a binder that does not easily remain in the pores of the porous adsorbent, for example, an aqueous acrylic resin is preferable.

In the present embodiment, the basis weight (coating amount) of the coating material (coating composition adhering to the substrate including the binder and the porous adsorbent) per ^{1 m 2 of the adsorbent is, for example, 150 to 450 g / m 2.} It may be 200 to 320 g / m ^2.

<Manufacturing method>
The method for producing an adsorbent according to the present embodiment includes a step of preparing a dispersion liquid of a porous carrier, a step of adhering a hydroxyl group-containing water-soluble polymer to the surface of the porous carrier to form a porous adsorbent, and a porous. It includes a step of preparing a slurry containing an adsorbent and a binder, a step of bringing the base material into contact with the slurry, and a step of drying the base material in contact with the slurry. The method for producing the adsorbent according to the present embodiment will be described below.

-Step of preparing the dispersion liquid of the porous carrier In this step, for example, the powder of the porous carrier is immersed in water and stirred to obtain the dispersion liquid of the porous carrier.

-Step of adsorbing a hydroxyl group-containing water-soluble polymer to form a porous adsorbent This step is a characteristic part of the method for producing an adsorbent according to the present embodiment, and the porous carrier obtained in the above step. By adding a hydroxyl group-containing water-soluble polymer to the dispersion and bringing the hydroxyl group-containing water-soluble polymer into contact with the porous carrier, the hydroxyl group-containing water-soluble polymer is adsorbed on the surface of the porous carrier. Obtain a quality adsorbent. The contact between the porous carrier and the hydroxyl group-containing water-soluble polymer is carried out for a predetermined time (for example, 0.5 hours to 3.0 hours) after the hydroxyl group-containing water-soluble polymer is added to the dispersion liquid of the porous carrier. Time) It can be done by stirring.

Adhesion of the hydroxyl group-containing water-soluble polymer to the surface of such a porous carrier is performed by contacting the porous carrier with the hydroxyl group-containing water-soluble polymer before mixing the binder, that is, in the absence of the binder. It is formed. When a porous carrier and a hydroxyl group-containing water-soluble polymer are mixed in the presence of a binder, the binding of the binder to the porous carrier inhibits the bond between the porous carrier and the hydroxyl group-containing water-soluble polymer, resulting in hydroxyl group. The group-containing water-soluble polymer does not adhere to the surface of the porous carrier.

-Step of preparing a slurry containing a porous adsorbent and a binder In this step, for example, the slurry is added to the dispersion liquid containing the porous adsorbent obtained in the above step and stirred for a predetermined time. To prepare. The amount of the binder added (solid content) is not particularly limited. For example, it may be 10 to 80% by mass, or 20 to 40% by mass with respect to the porous adsorbent.

-Step of bringing the base material into contact with the slurry In this step, the slurry containing the porous adsorbent and the binder obtained in the above step is brought into contact with the base material. Here, the contact between the slurry and the base material can be carried out, for example, by coating, impregnating, or coating the base material with the slurry.

-Step of drying the base material in contact with the slurry In this step, the base material after contact with the slurry is dried. The drying temperature and the drying time are not particularly limited and can be appropriately set depending on the situation.

The adsorbent according to this embodiment is intended to be applied to various devices or members in a vehicle or indoors. It can be used in various forms depending on the application and the applied member.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

<Example 1A>
100 g of powdered coconut shell activated carbon having a BET specific surface area of 1100 m ² / g and a median diameter (D50) of 25 μm was immersed in 295 g of water, and dispersed by stirring. 8 g of sodium carboxymethylol cellulose (CMC · Na) was gradually added to the obtained dispersion, and the mixture was stirred for 2 hours to be sufficiently blended with activated carbon. Next, 61 g of an acrylic emulsion binder (solid content: 50% by mass) was added and stirred to prepare a slurry. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 1A). The coating amount of sample 1A was 269 g / m ² and the pH was 6.4.
As CMC / Na, "CMC1110" (weight average molecular weight Mw: about 250,000, manufactured by Daicel Corporation) was used, and as the acrylic emulsion binder, "Boncoat AB-886" (manufactured by DIC Corporation) was used.

<Example 2A>
Conditions and methods similar to Example 1A except that CMC / Na "CMC1110" (Mw: about 250,000, manufactured by Daicel) was replaced with CMC / Na "CMC1150" (Mw: about 500,000, manufactured by Daicel). To prepare the slurry. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 2A). The coating amount of sample 2A was 262 g / m ² and pH 6.5.

<Example 3A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that 1 g of hydrochloric acid (36% by mass) was added to water before adding the coconut shell activated carbon. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 3A). The coating amount of sample 3A was 260 g / m ² and pH 5.5.

<Example 4A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that 2 g of potassium carbonate was added to water before adding the coconut shell activated carbon. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 4A). The coating amount of sample 4A was 266 g / m ² and pH 9.3.

<Example 5A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that CMC / Na was changed from 8 g to 4 g. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 5A). The coating amount of sample 5A was 251 g / m ² and pH 6.5.

<Example 6A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that CMC / Na was changed from 8 g to 2 g. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 6A). The coating amount of sample 6A was 263 g / m ² , and the pH was 6.6.

<Example 7A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that the coconut shell activated carbon having a BET specific surface area of 1100 m ^{2 / g was changed to 1300 m 2 / g coconut shell activated carbon.} The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 7A). The coating amount of sample 7A was 255 g / m ² and pH 6.5.

<Example 8A>
A slurry was prepared under the same conditions and methods as in Example 1A, except that the coconut shell activated carbon having a BET specific surface area of 1100 m ^{2 / g was changed to 1500 m 2 / g coconut shell activated carbon.} The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 8A). The coating amount of sample 8A was 265 g / m ² and pH 6.1.

<Example 1B>
Conditions and methods similar to Example 1A except that CMC / Na "CMC1110" (Mw: about 250,000, manufactured by Daicel) was replaced with CMC / Na "CMC2220" (Mw: about 1.64 million, manufactured by Daicel). To prepare the slurry. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 1B). The coating amount of sample 1B was 281 g / m ² and pH 6.5.

<Example 2B>
Conditions and methods similar to Example 1A except that CMC / Na "CMC1110" (Mw: about 250,000, manufactured by Daicel) was replaced with CMC / Na "CMC2240" (Mw: about 2 million, manufactured by Daicel). To prepare the slurry. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 2B). The coating amount of Sample 2B was 271 g / m ² , and the pH was 6.4.

<Example 3B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that 2 g of hydrochloric acid (36% by mass) was added to water before adding the coconut shell activated carbon. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 3B). The coating amount of sample 3B was 261 g / m ² and pH 5.2.

<Example 4B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that 2.5 g of potassium carbonate (K ₂ CO _{3) was added to water before adding the coconut shell activated carbon.} The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 4B). The coating amount of Sample 4B was 258 g / m ² , and the pH was 9.7.

<Example 5B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that CMC / Na was changed from 8 g to 12 g. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 5B). The coating amount of Sample 5B was 267 g / m ² and pH 6.6.

<Example 6B>
Prior to adding the coconut shell activated carbon, the slurry was prepared under the same conditions and methods as in Example 1A, except that 3 g of _{potassium carbonate (K 2} CO _{3) was added to water and the CMC / Na was changed from 8 g to 12 g.} Prepared. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 6B). The coating amount of sample 6B was 260 g / m ² , and the pH was 10.0.

<Example 7B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that CMC / Na was changed from 8 g to 20 g. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 7B). The coating amount of sample 7B was 255 g / m ² and pH 6.1.

<Example 8B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that the coconut shell activated carbon having a BET specific surface area of 1100 m ^{2 / g was changed to 950 m 2 / g coconut shell activated carbon.} The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 8B). The coating amount of sample 8B was 269 g / m ² and pH 6.1.

<Example 9B>
The coconut shell activated carbon with a BET specific surface area of 1100 m ^{2 / g was changed to 950 m 2} / g coconut shell activated carbon, and 3 g of _{potassium carbonate (K 2} CO ₃ ) was added to water before the coconut shell activated carbon was added. Except for the above, a slurry was prepared under the same conditions and methods as in Example 1A. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 9B). The coating amount of sample 9B was 251 g / m ² and pH 10.0.

<Example 10B>
A slurry was prepared under the same conditions and methods as in Example 1A, except that CMC / Na and an acrylic emulsion binder were added together to the dispersion of coconut shell activated carbon. The obtained slurry was applied to a sheet-shaped non-woven fabric (Kurashiki Textile Manufacturing E-90, basis weight 90 g / m ² ) and dried at 80 ° C. to obtain a sheet-shaped adsorbent (Sample 10B). The coating amount of sample 10B was 262 g / m ² and pH 6.5.

<Performance measurement and evaluation method>
1. 1. Performance of removing complex odors The residual ratio (%) of triethylamine, acetic acid, and toluene after removal with an adsorbent is measured and calculated by the method shown in (i) below. Next, by substituting the residual rates (%) of these three types of odor components into the variables A, B, and C in the model formula (I) shown in the following (ii), the residual rate (%) of the complex odor can be obtained. calculate. The lower the residual rate (%) of the complex odor, the better the removal performance of the complex odor. The results are shown in Table 1.

(I) Method for measuring residual rate (%) of three types of odorous components ・ Residual rate of trimethylamine (%)
The _{N 2} to 4L filled to 5L bag. Each sheet-shaped adsorbent cut into a size of 2 cm × 2 cm is enclosed in a bag filled with _{N 2.} The bag is then filled with trimethylamine, adjusted to a concentration of 10 ppm. After 8 hours, the trimethylamine concentration in the bag is measured.
The value obtained by subtracting the concentration after 8 hours from the initial concentration of trimethylamine is divided by the initial concentration and multiplied by 100 to obtain the trimethylamine residual rate A (%).
・ Residual rate of acetic acid (%)
The _{N 2} to 4L filled to 5L bag. Each sheet-shaped adsorbent cut into a size of 2 cm × 2 cm is enclosed in a bag filled with _{N 2.} Next, the bag is filled with acetic acid after adjusting the concentration to 10 ppm. After 8 hours, the acetic acid concentration in the bag is measured.
The value obtained by subtracting the concentration after 8 hours from the initial concentration of acetic acid is divided by the initial concentration, and the number multiplied by 100 is taken as the acetic acid residual ratio B (%).
・ Toluene residual rate (%)
The _{N 2} to 4L filled to 5L bag. Each sheet-shaped adsorbent cut into a size of 2 cm × 2 cm is enclosed in a bag filled with _{N 2.} Next, the bag is filled with toluene after adjusting the concentration to 10 ppm. After 8 hours, the toluene concentration in the bag is measured.
The value obtained by subtracting the concentration after 8 hours from the initial concentration of toluene is divided by the initial concentration, and the number multiplied by 100 is defined as the toluene residual rate C (%).

(Ii) Model formula Residual rate of complex odor (%) = A × α + B × β + C × γ (I)
A: trimethylamine residual rate (%)
B: Acetic acid residual rate (%)
C: Toluene residual rate (%)
α = β = γ = 1/3

2. Adsorbent pH
The pH of the sheet-shaped adsorbent was measured by a method according to JIS K 1474, except that the sample amount of the sheet-shaped adsorbent was evaluated at 1 g. The results are shown in Table 1.

3. 3. Specific Surface Area of Adsorbent The specific surface area of the adsorbent was measured by measuring the pore distribution with Quadrasorb SI (manufactured by Kantachrome). The results are shown in Table 1.

4. Amount of OH groups The amount of OH groups contained in the adsorbent is an XPS (X-ray photoelectron spectroscopy) device in which the adsorbent component, that is, the porous adsorbent containing activated carbon and CMC / Na, is physically peeled off from the sheet-shaped adsorbent. The amount of Na (atm%) of CMC / Na in the adsorbent component was quantified in. Since the OH group is Na: OH = 1: 2 in CMC 1 UNIT, the amount of OH group was estimated from the amount of Na and calculated. The results are shown in Table 1.

3A to 3D show the relationship between the amount of OH groups (atm%) contained in CMC / Na and the residual rate (%) of the odorous component in Examples 1A (Ex.1A) and 2A (Ex.2A). , Example 5A (Ex.5A), Example 6A (Ex.6A), Example 1B (Ex.1B), Example 2B (Ex.2B), Example 5B (Ex.5B) and Example 7B (Ex.7B). It is a graph.
FIG. 3A shows the relationship between the amount of OH groups and the residual rate (%) of the complex odor, and FIGS. 3B to 3D show the relationship between the amount of OH groups and the residual rate (%) of the single odor.
From FIG. 3A, it can be seen that the removal performance for the complex odor is excellent in the range of 1.0 to 3.8 atm% of the OH group amount. Further, from FIGS. 3B to 3D, the influence of the amount of OH groups on the removal performance of the single odor component is larger and more effective for trimethylamine (alkaline) and acetic acid (acidic) than for toluene (non-polar). You can see that.

4A to 4D show the relationship between the pH of the adsorbent and the residual rate (%) of the odorous component in Example 1A (Ex.1A), Example 3A (Ex.3A), Example 4A (Ex.4A), and FIG. It is the graph which summarized about Example 3B (Ex.3B) and Example 4B (Ex.4B).
FIG. 4A shows the relationship between the pH of the adsorbent and the residual rate (%) of the composite odor, and FIGS. 4B to 4D show the relationship between the pH of the adsorbent and the residual rate (%) of the single odor.
From FIG. 4A, it can be seen that the adsorbent has excellent removal performance against complex odors in the range of 5.4 to 9.5 atm%. Further, from FIGS. 4B to 4D, the influence of the pH of the adsorbent on the removal performance of the single odor component is larger and more effective for trimethylamine (alkaline) and acetic acid (acidic) than for toluene (non-polar). It turns out that there is.

5A to 5D show the relationship between the specific surface area (m ² / g) of the adsorbent and the residual ratio (%) of the odorous component in Examples 1A (Ex.1A), 7A (Ex.7A), and Examples. It is the graph which summarized about 8A (Ex.8A), and Example 8B (Ex.8B).
FIG. 5A shows the relationship between the specific surface area of the adsorbent (m ² / g) and the residual ratio (%) of the composite odor, and FIGS. 3B to 3D show the specific surface area of the adsorbent (m ² / g) alone. The relationship with the residual rate (%) of odor is shown.
From FIG. 5A, it can be seen that when the specific surface area of the adsorbent is 300 m ² / g or more, the removal performance against the complex odor is excellent. Further, from FIGS. 5B to 5D, the influence of the pH of the adsorbent on the removal performance of the single odor component is larger and more effective for trimethylamine (alkaline) and toluene (non-polar) than for acetic acid (acidic). It turns out that there is.

The present invention is not limited to the above embodiment, and can be variously modified at the implementation stage without departing from the gist thereof. In addition, each embodiment may be carried out in combination as appropriate, and in that case, the combined effect can be obtained. Further, the above-described embodiment includes various inventions, and various inventions can be extracted by a combination selected from a plurality of disclosed constituent requirements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the problem can be solved and the effect is obtained, the configuration in which the constituent requirements are deleted can be extracted as an invention.

Claims (7)

An adsorbent containing a base material, a porous carrier, a porous adsorbent containing a hydroxyl group-containing water-soluble polymer, and a binder. The porous adsorbent is a hydroxyl group-containing water-soluble material on the surface of the porous carrier. The amount of hydroxyl groups contained in the hydroxyl group-containing water-soluble polymer is 1.0 to 3.8 atm%, and the pH of the adsorbent is 5.4 to 9.5. Yes, the adsorbent has a specific surface area of 300 m ² / g or more. The porous adsorbent is obtained by adding the hydroxyl group-containing water-soluble polymer to the dispersion liquid of the porous carrier that does not contain the binder, and bringing the hydroxyl group-containing water-soluble polymer into contact with the porous carrier. The adsorbent according to claim 1, which is formed by. The adsorbent according to claim 1 or 2, wherein the hydroxyl group-containing water-soluble polymer is a cellulosic resin. The adsorbent according to any one of claims 1 to 3, wherein the hydroxyl group-containing water-soluble polymer is carboxymethyl cellulose or a salt thereof. The adsorbent according to any one of claims 1 to 4, wherein the porous carrier is activated carbon. The adsorbent according to any one of claims 1 to 5, wherein the base material is a sheet-shaped breathable base material. The method for producing an adsorbent according to any one of claims 1 to 6.
To prepare a dispersion of the porous carrier,
By adding the hydroxyl group-containing water-soluble polymer to the dispersion and bringing the hydroxyl group-containing water-soluble polymer into contact with the porous carrier, the hydroxyl group-containing water-soluble polymer is brought to the surface of the porous carrier. To obtain the porous adsorbent that is attached,
To prepare a slurry containing the porous adsorbent and the binder,
Bringing the substrate into contact with the slurry and drying the substrate in contact with the slurry.
A method for producing an adsorbent containing.

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