Honeycomb structure and gas recovery device

Abstract

Provided is a honeycomb structure which has a plurality of cell channels that pass through the inside of the structure and are defined by a partition wall 15. The partition wall 15 contains porous silica and water-soluble cellulose. The honeycomb structure has a dry mass loss rate of 3.0% or less after immersion in water for 24 hours.

Description

Honeycomb structure and gas recovery device

[0001] This invention relates to a honeycomb structure and a gas recovery device.

[0002] To realize a decarbonized society, there is a growing need for technologies to capture and utilize greenhouse gases (e.g., carbon dioxide) from the atmosphere and exhaust gases. A representative conventional carbon dioxide (CO2) capture technology is Direct Air Capture (DAC), which adsorbs CO2 from the atmosphere. DAC includes several types, such as liquid absorption, membrane separation, and solid adsorption. Among these, the use of a honeycomb structure supporting a CO2 adsorbent is being considered for the solid adsorption method. A honeycomb structure with such a structure can adsorb CO2 by circulating a CO2-containing treatment gas through the cell. Furthermore, the CO2 adsorbed in the honeycomb structure can be desorbed by circulating a purge gas (desorption gas), such as water vapor, through the cell.

[0003] As a honeycomb structure capable of supporting adsorbents such as CO2 adsorbents, for example, Patent Document 1 describes a honeycomb-shaped silica gel molded body (honeycomb structure) manufactured by kneading a mixture containing powdered silica gel and an organic binder, extruding the kneaded mixture into a honeycomb shape, and drying and / or calcining the extruded body. Furthermore, Patent Document 1 states that if the organic binder is a water-soluble organic substance, the water resistance of the honeycomb-shaped silica gel molded body is insufficient, and therefore it is necessary to use an inorganic binder in combination and to carry out calcination.

[0004] Furthermore, Patent Document 2 describes a silica gel molded body (honeycomb structure) produced by adding and mixing an inorganic binder made of a double-chain structured clay mineral together with an organic binder to silica gel to form a mixture, molding the mixture, and then drying and firing it. Patent Document 2 also states that firing removes the organic binder and provides bonding properties for the inorganic binder, thereby improving the water resistance of the silica gel molded body.

[0005] Japanese Patent Publication No. 1-51467 Publication No. 10-273372

[0006] CO2 adsorbed onto a honeycomb structure is desorbed by circulating a purge gas such as water vapor through the cell. However, if the honeycomb structure has low water resistance, the desorption of CO2 may result in a decrease in strength or damage to the honeycomb structure. According to the technologies described in Patent Documents 1 and 2, firing is necessary to ensure the water resistance of the honeycomb structure, but firing generates CO2 and increases manufacturing costs. Furthermore, as sintering progresses through firing, the specific surface area of ​​porous silica such as silica gel decreases, which may reduce the adsorption performance when an adsorbent is supported. Although the above explanation uses the case where the target gas is CO2 as an example, similar problems exist when adsorbing other target gases.

[0007] The present invention was made to solve the above-mentioned problems, and aims to provide a honeycomb structure with excellent water resistance that can be manufactured without firing, and a gas recovery device equipped with the honeycomb structure.

[0008] The inventors of the present invention conducted extensive research on honeycomb structures equipped with partitions containing porous silica. As a result, they discovered that by using porous silica in combination with water-soluble cellulose, water resistance can be improved without firing, thus completing the present invention. Specifically, the present invention is illustrated as follows.

[0009] <1> A honeycomb structure having a plurality of cell channels that pass through the interior of the honeycomb structure and are partitioned by partition walls, wherein the partition walls contain porous silica and water-soluble cellulose, and the dry mass loss rate after 24 hours of water immersion is 3.0% or less.

[0010] <2> The porous silica has a BET specific surface area of ​​200 m 2 A honeycomb structure as described in <1>, having a value of 1 / g or more.

[0011] <3> The honeycomb structure according to <1> or <2>, wherein the partition wall contains 10 to 40 parts by mass of the water-soluble cellulose per 100 parts by mass of the porous silica.

[0012] <4> The honeycomb structure according to <1> or <2>, wherein the water-soluble cellulose is one or more selected from ethylcellulose, hydroxyethylmethylcellulose, methylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and carboxymethylcellulose.

[0013] <5> The honeycomb structure according to any one of <1> to <3>, wherein the partition wall further comprises a resin binder.

[0014] <6> The honeycomb structure according to <5>, wherein the resin binder is one or more selected from polyvinyl alcohol, polyethylene oxide, polybutadiene, acrylic acid esters, methacrylic acid esters and silicones, partially benzalized polyvinyl alcohol, (meth)acrylic resin, polyacrylate resin, polynitrile resin, polychloroprene, polyvinyl chloride, polyvinylidene fluoride, polyolefins, poly(tetrafluoroethylene), polyurethanes, phenols, urethanes, polyvinyl butyral, ethylene-vinyl acetate, vinyl acetates and synthetic rubbers.

[0015] <7> The honeycomb structure according to any one of <1> to <6>, wherein an adsorbent capable of adsorbing and desorbing a target gas is supported on the partition wall.

[0016] <8> The honeycomb structure according to <7>, wherein the adsorbent is polyethyleneimine.

[0017] <9> A gas recovery device comprising one or more honeycomb structures as described in <7> or <8>.

[0018] According to the present invention, it is possible to provide a honeycomb structure with excellent water resistance that can be manufactured without firing, and a gas recovery device equipped with the honeycomb structure.

[0019] This is a schematic diagram of a cross-section perpendicular to the direction in which the cells of a honeycomb structure according to an embodiment of the present invention extend. This is a schematic diagram of a cross-section along the line a-a' of the honeycomb structure in Figure 1A.

[0020] The honeycomb structure of the present invention has multiple cell channels that pass through the interior and are partitioned by partition walls, the partition walls containing porous silica and water-soluble cellulose, and the dry mass loss rate after 24 hours of water immersion is 3.0% or less. The honeycomb structure of the present invention can improve water resistance without firing by combining porous silica and water-soluble cellulose to form partition walls. Furthermore, since the honeycomb structure of the present invention does not require firing, CO2 generation and manufacturing costs can be reduced.

[0021] The embodiments of the present invention will be described in detail below with reference to the drawings. The present invention is not limited to the following embodiments, and it should be understood that modifications, improvements, etc., to the following embodiments, based on the ordinary knowledge of those skilled in the art, without departing from the spirit of the invention, also fall within the scope of the present invention.

[0022] Figure 1A is a schematic diagram of a cross-section of a honeycomb structure according to an embodiment of the present invention, perpendicular to the direction in which the cell channels extend. Figure 1B is a schematic diagram of a cross-section of the honeycomb structure in Figure 1A along the line a-a' (a cross-section parallel to the direction in which the cell channels extend).

[0023] As shown in Figures 1A and 1B, the honeycomb structure according to an embodiment of the present invention has a plurality of cells 14 (cell channels) that pass through its interior and are partitioned by partition walls 15. Specifically, the honeycomb structure comprises an outer peripheral wall 11 and partition walls 15 disposed on the inner circumferential side of the outer peripheral wall 11, partitioning the plurality of cells 14 that extend from the inlet end face 12 to the outlet end face 13. The plurality of cells 14 are arranged parallel to each other. The honeycomb structure is a flow-through type with both end faces (inlet end face 12 and outlet end face 13) of each cell 14 being open. An adsorbent 16 capable of adsorbing and desorbing the target gas can be carried on the partition walls 15. The adsorbent 16 can also be carried on the outer peripheral wall 11 facing the cells 14. The adsorbent 16 can be carried not only on the surfaces of the partition walls 15 and the outer peripheral wall 11, but also in the pores of the partition walls 15 and the outer peripheral wall 11. With this configuration, adsorption and desorption of the target gas can be achieved.

[0024] Herein, in this specification, "processed gas" means various gases containing the target gas. The processed gas is not particularly limited, but examples include exhaust gases emitted from factories and power plants, and atmospheric air. The exhaust gas is not particularly limited, but examples include combustion exhaust gases generated when burning fossil fuels, coal gas (from gasified coal), and natural gas at thermal power plants and steel mills. The target gas is not particularly limited, but examples include carbon dioxide (CO2), carbon monoxide (CO), and nitrogen oxides (NOx). x ), sulfur oxides (SO x Examples include acidic gases such as hydrogen sulfide (H2S). Among these, the honeycomb structure according to the embodiment of the present invention is particularly useful for recovering greenhouse gases such as carbon dioxide and carbon monoxide contained in combustion exhaust gas and the atmosphere.

[0025] The partition wall 15 contains porous silica and water-soluble cellulose. The outer periphery wall 11 can also contain porous silica and water-soluble cellulose, similar to the partition wall 15. By combining porous silica and water-soluble cellulose to form the partition wall 15 and the outer periphery wall 11, water resistance can be improved without firing. The details of the mechanism by which this water resistance is improved are not known, but according to analysis results by FT-IR (Fourier transform infrared spectroscopy), it may be due to the formation of Si-O-C bonds between the porous silica and water-soluble cellulose.

[0026] The partition wall 15 preferably contains 10 to 40 parts by mass of water-soluble cellulose per 100 parts by mass of porous silica, and more preferably 10 to 35 parts by mass of water-soluble cellulose. Similarly, the outer periphery wall 11 preferably contains porous silica and water-soluble cellulose in the above proportions. By controlling the ratio of porous silica to water-soluble cellulose within the above range, the desired water resistance can be easily obtained.

[0027] Porous silica has a BET specific surface area of ​​200 m². 2 It is preferable that the amount be 250m or more. 2It is preferable that the BET specific surface area is 1 / g or more. Porous silica having a BET specific surface area within this range makes it easier to obtain the desired water resistance. The upper limit of the BET specific surface area of ​​porous silica is not particularly limited, but for example, 800 m² is preferable. 2 / g, 600m 2 / g or 500m 2 This can be expressed as / g. Here, the BET specific surface area of ​​porous silica as used herein means that it is measured according to the BET single-point method in accordance with JIS Z8830:2013.

[0028] The porous silica is not particularly limited, and silica gel, precipitated silica, gel-type silica, amorphous silica-alumina, zeolite, mesoporous silica, etc., can be used. At the raw material stage, commercially available products in various forms such as powder, granules, and other forms can be used. In particular, from the viewpoint of moldability into a honeycomb structure, it is preferable that the average particle size of the porous silica used as a raw material is 0.5 to 20 μm. Here, the average particle size in this specification means the particle size at 50% of the cumulative value of the particle size distribution obtained by laser diffraction and scattering (D50).

[0029] The water-soluble cellulose is not particularly limited, and commercially available products in various forms, such as powder, granules, and other forms, can be used at the raw material stage. Examples of water-soluble cellulose include ethylcellulose, hydroxyethyl methylcellulose, methylcellulose, hydroxypropyl methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and carboxymethylcellulose. These can be used individually or in combination of two or more. Furthermore, by using these, the water resistance of the honeycomb structure can be stably improved.

[0030] The honeycomb structure according to the embodiment of the present invention has a dry mass reduction rate of 3.0% or less, preferably 2.9% or less, and more preferably 2.8% or less after 24 hours of immersion in water. A dry mass reduction rate within this range indicates excellent water resistance. Here, water at 25°C is used for the 24-hour immersion. The dry mass reduction rate after 24 hours of immersion in water is calculated by the following formula: Dry mass reduction rate after 24 hours of immersion in water (%) = (W1 - W2) / W1 × 100 In the formula, W1 is the mass of the honeycomb structure before 24 hours of immersion, and W2 is the mass of the honeycomb structure after 24 hours of immersion.

[0031] The partition wall 15 may further contain a resin binder as needed. Similarly, the outer periphery wall 11 may further contain a resin binder as needed. By including a resin binder in the partition wall 15 and the outer periphery wall 11, cracks caused by drying of the honeycomb structure can be suppressed.

[0032] The resin binder is not particularly limited, and commercially available products in various forms, such as liquid or emulsion, can be used at the raw material stage. Examples of resin binders include polyvinyl alcohol, polyethylene oxide, polybutadiene, acrylic acid esters, methacrylic acid esters, and silicones, partially benzalized polyvinyl alcohol, (meth)acrylic resin, polyacrylate resin, polynitrile resin, polychloroprene, polyvinyl chloride, polyvinylidene fluoride, polyolefins, poly(tetrafluoroethylene), polyurethanes, phenols, urethanes, polyvinyl butyral, ethylene-vinyl acetate, vinyl acetate, and synthetic rubbers. These can be used individually or in combination of two or more. By using these, cracks in the honeycomb structure can be stably suppressed.

[0033] The shape of the end faces (the inlet end face 12 and the outlet end face 13) of the honeycomb structure is not particularly limited, and may be, for example, a round shape such as a circular shape, an elliptical shape, a racetrack shape, or an oval shape, a polygonal shape such as a triangular shape or a quadrangular shape, or other irregular shapes. The outer shape of the honeycomb structure can typically be columnar. The honeycomb structure shown in FIGS. 1A and 1B is an example in which the end face shape is quadrangular and the whole is a quadrangular columnar shape.

[0034] The length in the direction in which the cells 14 of the honeycomb structure extend (the length from the inlet end face 12 to the outlet end face 13) is not particularly limited, and may be appropriately set according to the application and required performance. However, a longer length in the direction in which the cells 14 of the honeycomb structure extend can increase the adsorption amount of carbon dioxide, while an excessively long length leads to increased pressure loss. Therefore, the length is preferably 20 to 350 mm, more preferably 20 to 300 mm, and still more preferably 20 to 250 mm.

[0035] The diameter of each end face of the honeycomb structure is not particularly limited, and may be appropriately set according to the application and required performance. However, a larger diameter of each end face of the honeycomb structure can increase the adsorption amount of the target gas to be captured, while an excessively large diameter increases manufacturing difficulty. Therefore, the diameter is preferably 20 to 450 mm, more preferably 20 to 400 mm, and still more preferably 20 to 350 mm. Herein, in the present specification, the diameter of each end face of the honeycomb structure means the diameter when the end face is circular, and means the equivalent circle diameter when the end face is not circular.

[0036] In addition to the above components, the honeycomb structure (the partition walls 15 and the outer peripheral wall 11) may further contain known additives such as surfactants and pore-forming agents within a range that does not impair the effects of the present invention. Specific examples of surfactants include ethylene glycol, dextrin, fatty acid soap, and polyalcohol. These may be used alone or in combination of two or more thereof. Specific examples of pore-forming agents include wood flour, activated carbon, hollow resins, porous resins, hollow inorganic materials, and porous inorganic materials. These may be used alone or in combination of two or more thereof.

[0037] The thickness of the outer peripheral wall 11 is not particularly limited, but is preferably 0.1 to 4.0 mm, more preferably 0.2 to 3.0 mm, and still more preferably 0.3 to 2.5 mm from the viewpoint of securing strength. In this specification, the thickness of the outer peripheral wall 11 refers to the length in the normal direction of the outer peripheral surface from the boundary between the outer peripheral wall 11 and the outermost peripheral cells 14 or partition walls 15 to the outer peripheral surface of the honeycomb structure in a cross section orthogonal to the direction in which the cells 14 extend.

[0038] The thickness of the partition walls 15 is not particularly limited, but is preferably 50 µm or more, more preferably 80 µm or more, and still more preferably 100 µm or more from the viewpoint of securing strength. Further, from the viewpoint of suppressing pressure loss, the thickness of the partition walls 15 is preferably 50 to 600 µm, more preferably 80 to 550 µm, and still more preferably 100 to 500 µm.

[0039] It is preferable that the outer peripheral wall 11 and the partition walls 15 have the same thickness. By adopting such a configuration, it is possible to secure the strength of the honeycomb structure, suppress an increase in pressure loss, and increase the adsorption amount of the target gas to be captured.

[0040] The cell density of the honeycomb structure (the number of cells 14 per unit cross-sectional area) is not particularly limited, but is preferably 3 to 124 cells / cm 2 , more preferably 4 to 62 cells / cm 2 . By controlling the cell density within such a range, the effect of suppressing an increase in pressure loss, the effect of improving mechanical strength and the effect of increasing the adsorption amount of the target gas to be captured are easily obtained. When the cell density is less than 3 cells / cm 2 , the mechanical strength and the adsorption amount of the target gas to be captured tend to decrease. Further, when the cell density exceeds 124 cells / cm 2 , pressure loss tends to increase. Here, in this specification, the cell density is calculated by dividing the number of cells 14 of the honeycomb structure by the area of one end surface of the honeycomb structure excluding the outer peripheral wall 11.

[0041] The shape of the cells 14 in a cross-section perpendicular to the direction in which the cells 14 of the honeycomb structure extend is not particularly limited, but is preferably a quadrilateral (e.g., square), hexagon, octagon, circle, or a combination thereof. Among these, the shapes of the cells 14 are preferably square and hexagonal. By shaping the cells 14 in this way, the increase in pressure loss when gas flows through the honeycomb structure can be suppressed.

[0042] The adsorbent 16 is not particularly limited as long as it is capable of adsorbing and desorbing the target gas, and can be appropriately selected according to the type of target gas. For example, inorganic compounds, amine compounds, organometallic complexes, etc., can be used as adsorbents 16 that are effective for adsorbing target gases such as carbon dioxide (CO2). Alternatively, nanoporous ceramics or mesoporous silica supported with amine compounds and / or organometallic complexes may be used. These can be used alone or in combination of two or more. Examples of inorganic compounds are not particularly limited, but include calcium carbonate. Examples of amine compounds are not particularly limited, but include monoethanolamine (MEA), N-methyldiethanolamine (MDEA), polyethyleneimine, weakly basic anion exchange resins, and strongly basic anion exchange resins. Examples of organometallic complexes are not particularly limited, but include porous organometallic structures (MOF: Metal-Organic Framework) having a structure capable of adsorbing target gases in their pores. Among the above various adsorbents 16, amine compounds are preferred, secondary amines are more preferred, and polyethyleneimine is particularly preferred. By using such an adsorbent 16, the amount of gas to be captured that can be adsorbed can be stably improved.

[0043] The honeycomb structure according to the embodiment of the present invention can be used for adsorption (recovery) and desorption of target gases contained in a processing gas. Specifically, in the honeycomb structure according to the embodiment of the present invention, a processing gas containing the target gas is circulated through the cells 14 of the honeycomb structure, the target gas is adsorbed by the adsorbent 16 as the processing gas passes through the cells 14, and the processed gas with a reduced concentration of target gas can be discharged from the honeycomb structure. Alternatively, a desorption gas or heated desorption gas can be circulated through the cells 14 of the honeycomb structure in which the target gas has been adsorbed, and the target gas can be desorbed from the adsorbent 16 into the desorption gas as the desorption gas passes through the cells 14. Here, the desorption gas is not particularly limited as long as it is a gas capable of desorbing the target gas, but for example, water vapor can be used. The water vapor is preferably at a high temperature of 80°C or higher. The desorption gas may be heated by a heater or by mixing it with a high-temperature gas.

[0044] The method for manufacturing a honeycomb structure having the above-described structure is not particularly limited and can be carried out in accordance with known methods. For example, a honeycomb structure can be manufactured as follows. First, a clay mixture containing porous silica and water-soluble cellulose is extruded into a desired shape to produce a honeycomb molded body. At this time, the shape and density of each cell, the shape and thickness of the partition walls 15 and the outer peripheral walls 11 can be controlled by selecting a die and jig of an appropriate shape. The clay mixture may also contain a resin binder, a pore-forming agent, a dispersant, water, an organic solvent, etc., as needed. Next, the honeycomb molded body obtained above is dried and fired to obtain a honeycomb structure. The drying method is not particularly limited and conventional known drying methods such as hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, and freeze-drying can be used. Among these, a drying method combining hot air drying with microwave drying or dielectric drying is preferred because it can dry the entire honeycomb molded body quickly and uniformly.

[0045] The method for supporting the adsorbent 16 is not particularly limited, but for example, it can be carried out by the following steps: The honeycomb structure is immersed in a slurry containing the adsorbent 16, an organic binder, and a dispersion medium for a predetermined time, and excess slurry from the end faces and outer circumference of the honeycomb structure is removed by blowing and wiping. The dispersion medium can be water, an organic solvent (e.g., toluene, xylene, ethanol, n-butanol, ethyl acetate, butyl acetate, terpineol, dihydroterpineol, texanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether), or a mixture thereof. After that, the adsorbent 16 can be supported on the surface of the partition wall 15 or the like by drying the slurry. Drying can be done by heating the honeycomb structure to a temperature of, for example, 120 to 600°C. The series of steps—immersion, slurry removal, and drying—may be performed only once, but by repeating them multiple times, a desired amount of adsorbent 16 can be supported.

[0046] A gas recovery device according to an embodiment of the present invention includes the above-described honeycomb structure. This gas recovery device has a water-resistant honeycomb structure that can be manufactured without the above-described firing process, thereby reducing CO2 generation and manufacturing costs, and also providing good gas recovery performance.

[0047] A gas recovery device according to an embodiment of the present invention may further include a housing section that accommodates a honeycomb structure. Preferably, the housing section is connected to a pipe through which a processing gas containing the gas to be captured and a desorbed gas can be supplied and discharged. With a gas recovery device having such a structure, the adsorption (recovery) and desorption of the gas to be captured can be easily achieved.

[0048] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0049] <Materials Used> Porous Silica A: BET specific surface area 260 m² 2 / g, average particle size 10 μm, porous silica B: BET specific surface area 320 m²2 / g, average particle size 32 μm, porous silica C:BET specific surface area 320 m² 2 / g, average particle size 15μm Quartz: BET specific surface area 6m 2 / g, average particle size 5μm, kaolin: BET specific surface area 7m² 2 / g, average particle size 10 μm. Talc: BET specific surface area 12 m². 2 / g, average particle size 5μm. Water-soluble cellulose: methylcellulose resin binder: emulsion containing acrylic resin.

[0050] Water was added to each component in the proportions shown in Table 1, and the mixture was kneaded in a vacuum clay mixer to obtain clay. The amount of water added was adjusted so that the clay had a hardness suitable for molding. Next, the clay was molded using an extrusion molding machine with a predetermined die structure to obtain a honeycomb molded body. The die structure was selected so that the honeycomb molded body (honeycomb structure) after drying would meet the following conditions: Outer shape: rectangular prism; Cross-sectional shape of cells: rectangular; Length in the direction in which cells extend: 30 mm; Diameter of each end face: 60 mm; Thickness of outer wall: 1.0 mm; Thickness of partition wall: 150 μm; Cell density: 15.5 cells / cm 2

[0051]

[0052] Next, the honeycomb molded body was subjected to high-frequency dielectric drying, then dried for 3 minutes in an air atmosphere at a temperature of 120°C using a microwave dryer, and a predetermined amount was cut from both end faces to produce a honeycomb structure.

[0053] The honeycomb structure obtained above was evaluated as follows.

[0054] <Crack Occurrence Status> The honeycomb structure was visually inspected and the crack occurrence status was evaluated. In this evaluation, a rating of A indicates that no cracks were present in the partition walls or outer walls, while a rating of B indicates that slight cracks were present in the partition walls or outer walls, but at a level that was still usable.

[0055] <EDX> Using SEM-EDX, the elements contained in the septum and outer wall were identified.

[0056] <FT-IR> Using FT-IR, the chemical bonds of the components constituting the partition wall and outer wall were identified.

[0057] <Dry Mass Loss Rate After 24 Hours of Water Immersion> The honeycomb structure was immersed in water at 25°C for 24 hours, and the dry mass loss rate after 24 hours of water immersion was determined. The dry mass loss rate after 24 hours of water immersion was calculated based on the above formula.

[0058] The results of each of the above evaluations are shown in Table 2.

[0059]

[0060] As shown in Table 2, the honeycomb structures of Examples 1 to 7 contained porous silica and water-soluble cellulose, and the dry mass loss rate after 24 hours of water immersion was 3.0% or less, indicating good water resistance. In contrast, Comparative Example 1 could not be molded into a honeycomb structure, and no honeycomb structure was obtained. The honeycomb structure of Comparative Example 2 contained porous silica and water-soluble cellulose, but the dry mass loss rate after 24 hours of water immersion exceeded 3.0%, indicating insufficient water resistance. The honeycomb structures of Comparative Examples 3 to 5 did not contain porous silica, and the dry mass loss rate after 24 hours of water immersion exceeded 3.0%, indicating insufficient water resistance.

[0061] As can be seen from the above results, the present invention provides a honeycomb structure with excellent water resistance that can be manufactured without firing, and a gas recovery device equipped with the honeycomb structure.

[0062] 11 Outer wall 12 Inlet end face 13 Outlet end face 14 Cell 15 Partition wall 16 Adsorbent

Claims

1. A honeycomb structure having a plurality of cell channels that pass through the interior of the honeycomb structure and are partitioned by partition walls, wherein the partition walls contain porous silica and water-soluble cellulose, and the dry mass loss rate after 24 hours of water immersion is 3.0% or less.

2. The porous silica has a BET specific surface area of ​​200 m². 2 The honeycomb structure according to claim 1, wherein the amount is 1 / g or more.

3. The honeycomb structure according to claim 1 or 2, wherein the partition wall contains 10 to 40 parts by mass of the water-soluble cellulose per 100 parts by mass of the porous silica.

4. The honeycomb structure according to claim 1 or 2, wherein the water-soluble cellulose is one or more selected from ethylcellulose, hydroxyethylmethylcellulose, methylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and carboxymethylcellulose.

5. The honeycomb structure according to claim 1 or 2, wherein the partition wall further comprises a resin binder.

6. The honeycomb structure according to claim 5, wherein the resin binder is one or more selected from polyvinyl alcohol, polyethylene oxide, polybutadiene, acrylic acid esters, methacrylic acid esters and silicones, partially benzalized polyvinyl alcohol, (meth)acrylic resin, polyacrylate resin, polynitrile resin, polychloroprene, polyvinyl chloride, polyvinylidene fluoride, polyolefins, poly(tetrafluoroethylene), polyurethanes, phenols, urethanes, polyvinyl butyral, ethylene-vinyl acetate, vinyl acetates and synthetic rubbers.

7. The honeycomb structure according to claim 1 or 2, wherein an adsorbent capable of adsorbing and desorbing a target gas is supported on the partition wall.

8. The honeycomb structure according to claim 7, wherein the adsorbent is polyethyleneimine.

9. A gas recovery device comprising one or more honeycomb structures as described in claim 8.

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