JP2011177712A - Method for producing adsorption element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adsorbent which can adsorb and desorb an adsorbate in a low relative vapor pressure region and has efficiency suitable for a humidity control air conditioner. <P>SOLUTION: In an adsorption element formed by fixing the adsorbent to a carrier by means of a binder, the difference between adsorption amounts at relative humidities of 90% and 70% in an adsorption isotherm at 25°C is ≥0.05 g/g, and the difference between adsorption amounts at relative humidities of 5% and 28% therein is ≥0.05 g/g. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an adsorption element, and more particularly, to an adsorption element such as an adsorption refrigerator or a desiccant rotor for humidity control air conditioning.

  The adsorption element is composed of an adsorbent, a carrier, and a binder, and is formed in various structures such as a sheet shape, a flat plate shape, a fin shape, or a honeycomb shape. Although the adsorbent is largely involved in the adsorption performance, the actual adsorption performance is determined by the adsorption performance of the adsorption element itself, that is, the adsorbent fixed to the carrier by the binder.

  For example, in an air conditioning desiccant for humidity control, it is desired that regeneration at as low a temperature as possible is possible. As a result, exhaust heat that has been thrown away so far can be used, resulting in energy-saving air conditioning. In order to regenerate at a temperature as low as possible when dehumidifying high-humidity air, it is desirable that the adsorption amount difference between the adsorption relative humidity and the desorption relative humidity in the high relative humidity region be as large as possible as the adsorption element. In addition, when humidifying dry air in winter or the like, it must be possible to adsorb moisture from low-humidity air, regenerate at low temperature, and humidify with the desorbed moisture. For this purpose, it is desirable that the difference in the amount of adsorption between the relative humidity for adsorption and the relative humidity for desorption in a low relative humidity region including 10% or less is as large as possible.

  Among the conventionally known adsorbents, aluminophosphate (ALPO) having a specific structure can be cited as a relatively high performance material that can meet the above requirements (Patent Document 1). However, in this document, there is no disclosure or suggestion of what kind of adsorption performance it has when supported on a carrier.

  The adsorption performance of an adsorption element (referred to an adsorbent-supported material) is expected to change depending on the type, combination, and fixing method of the carrier and binder. An example of studying adsorption performance of the adsorption element itself There are few literatures, especially reports of adsorption isotherms.

As a typical example, a honeycomb rotor as an adsorbing element is known in which silicate or zeolite is supported on a ceramic fiber, and its adsorption isotherm is disclosed (Non-Patent Document 1, FIG. 9).
In this document, the authors make honeycomb rotors by supporting silicate or zeolite by different supporting methods, specifically, by carrying by synthesis reaction or by carrying by impregnating. The adsorption performance (adsorption isotherm) of the rotor is shown in FIG. 9, and it can be understood that the shape of the curve varies depending on the type of adsorbent, the type of carrier, and the loading method.
In other words, even if the adsorption isotherm of the adsorbent is known, the adsorption isotherm of the adsorption element when it is supported on the carrier has a completely different curve depending on the combination of the constituent materials, the loading conditions, etc. It is understood that it cannot be predicted.

In addition, in applications where moisture is adsorbed from low-humidity air while dehumidifying, and heated by a low-temperature heat source to release the adsorbed moisture and humidify, the low humidity region, specifically relative humidity Adsorption characteristics for 10% or less are important. However, Document 1 does not describe such a low humidity region.
Therefore, by examining in detail the adsorption characteristics from low humidity to high humidity of the adsorption elements that can be combined by the composition of the adsorption elements, including the adsorbent, and the supporting conditions, the components, adsorption element preparation conditions, etc. The adsorbing element that can deal with various humidity control conditions such as dehumidification and humidification is completed for the first time by examining the relationship between the adsorption characteristics from low humidity to high humidity in detail.

JP-A-9-178292 7th International Conference on Fundamentals of Adsorption May 20-25, 2001 Nagasaki

  However, the performance of the adsorption element disclosed in Non-Patent Document 1 is not sufficient, and it has not been able to sufficiently meet market demands.

  Another object of the present invention is to provide an adsorbing element for realizing a desiccant air conditioning apparatus for humidity control that enables both dehumidification of high-humidity air and humidification of low-humidity air.

  As a result of intensive studies to solve the above problems, the present inventors have found that the difference in adsorption amount between the relative humidity of 28% and the relative humidity of 5% is 0.05 g / g or more in the adsorption isotherm at 25 ° C. In addition, an adsorption element having a difference in adsorption amount between 70% relative humidity and 90% relative humidity of 0.05 g / g or more, preferably a difference in adsorption amount between 28% relative humidity and 7% relative humidity is 0.05 g. The present invention was completed by using an adsorbing element having a difference in adsorption amount of 0.05 g / g or more between the relative humidity of 72% and the relative humidity of 90%.

  According to the present invention, it is possible to realize a desiccant air conditioner for humidity control that can perform both dehumidification of high-humidity air and humidification of low-humidity air, which could not be solved by the prior art. In addition, regeneration at a low temperature of 50 ° C. or lower is also possible, which is effective for use of exhaust heat that has not been used so far.

Definition of adsorption performance:
When regenerating high-humidity air at a low temperature, for example, dehumidify air with a relative humidity of about 90% at 35 ° C in summer, and use this air for regeneration by using exhaust heat or the like to make it 40 ° C. Then, the relative humidity of about 70% becomes the humidity of the desorption air. Furthermore, when attempting to reproduce at a lower temperature, the humidity of the desorbed air becomes higher, for example, 72%.

  In addition, when humidifying low-humidity air, for example, when humidifying a room or the like using air having a relative humidity of 28% at 12 ° C. in winter, it is necessary to absorb moisture from the air. Is about 28%, and when the air is heated to 40 ° C. using low-temperature waste heat or the like and is rehydrated and dehumidified, the relative humidity for desorption becomes about 5%. Further, if the reproduction is performed at a lower temperature, the humidity of the desorption air becomes higher, for example, 7%.

  An adsorbing element capable of dehumidification and humidity adjustment in both high and low humidity air is required. For this purpose, the difference in the amount of adsorption at the relative humidity between the adsorption and desorption must be large.

  The difference in adsorption amount differs depending on the amount of air to be processed and the temperature and humidity conditions, but the difference in adsorption amount is larger. For example, a household dehumidifier has a dehumidifying performance of about 6 L / day, but since the rotational speed of the rotor is about 30 times / h and the weight is about 160 g, the dehumidifying amount of one rotor is about 8 g / day. The difference in adsorption amount per weight of the adsorption element is about 0.05 g / g.

  From these facts, as the desirable adsorption performance of the adsorption element, the adsorption amount between the relative humidity of 28% and the relative humidity of 5% in the adsorption isotherm at 25 ° C. is expressed by the difference in adsorption amount per weight of the adsorption element. Difference between the relative humidity of 70% and the relative humidity of 90% is more than 0.05 g / g, preferably an adsorption element having a relative humidity of 28% and a relative humidity of 7 %, The difference in the amount of adsorption is 0.05 g / g or more, and the difference in the amount of adsorption between the relative humidity 72% and the relative humidity 90% is 0.05 g / g or more.

Adsorption element:
The adsorption element includes an adsorbent, a binder, and a carrier. The adsorbing element according to the present invention includes a member that exhibits an adsorbing function such as a sheet shape, a flat plate shape, and a fin shape, and parts having various structures that exhibit an adsorbing function such as a honeycomb shape obtained by processing them. included.

Adsorbent:
The adsorbent used in the present invention is not particularly limited as long as the adsorbing element produces the adsorbing performance as described above, but usually silica gel, zeolite, activated carbon, alumina, polymer sorbent, ion exchange. Examples thereof include resins.

Among these, zeolite that can easily adsorb water vapor is preferable. In the aluminosilicate zeolite, the silica-alumina ratio (SiO ₂ / Al ₂ O ₃ molar ratio) is 5.5 or more, preferably 6 or more, more preferably 7 or more. Among zeolites, crystalline aluminophosphates containing at least Al and P in the skeleton, which can more easily desorb water vapor at a low temperature, are more preferable.

  When these adsorbents are used, particularly preferred aluminophosphates, the carrier constituting the adsorbing element, the type of binder, or the method for adjusting and fixing the aqueous slurry containing the adsorbent when adhering to the carrier are described. It is relatively easy to produce an adsorption element having the adsorption performance of the present invention from a wide range.

  On the other hand, in the case of other adsorbents, for example, in the case of an aluminosilicate zeolite, a zeolite having a relatively high silica-alumina ratio is selected, and a carrier and a binder are also preferable types from those exemplified below. It is considered that the adsorbing element of the present invention can be obtained by selecting conditions suitable for the zeolite for the adjustment method and fixing method of the aqueous slurry.

In the adsorption isotherm of water vapor in the adsorption element, the amount of adsorption increases at a high relative pressure portion (between 70% relative humidity and 90% relative humidity) because there are mesopores (mesopores) in the adsorption element. Suggests that. The mesopore is usually called a mesopore when the adsorbent adheres to the carrier, and the gap formed between the adsorbent particles or between the adsorbent and the carrier is generally called a mesopore. It corresponds to the size.
That is, in order to obtain the adsorbing element of the present invention, it is preferable to form mesopores in the adsorbing element when the adsorbent is fixed to the carrier.

  The size of the adsorbent is usually from 0.1 to 300 microns, preferably from 0.5 to 100 microns, more preferably from 1 to 50 microns, and most preferably from 2 to 20 microns in that it tends to form mesopores.

Aluminophosphates:
The aluminophosphates used in the present invention (hereinafter sometimes abbreviated as ALPOs) are crystalline aluminophosphates defined by IZA (International Zeolite Association).

  In the crystalline aluminophosphate, atoms constituting the skeletal structure are aluminum and phosphorus, and a part thereof may be substituted with other atoms. Among them, I) aluminum is a heteroatom (Me1: where Me1 belongs to the third or fourth period of the periodic table, from elements of 2A group, 7A group, 8 group, 1B group, 2B group, 3B group (except Al) Me-aluminophosphate partially substituted with (ii) phosphorus is a heteroatom (Me2: where Me2 is a group 4B element belonging to the third or fourth period of the periodic table) From the standpoint of adsorption properties, Me-aluminophosphate substituted with III or III) Me-aluminophosphate in which both aluminum and phosphorus are substituted with heteroatoms (Me1 and Me2 respectively) is preferable.

  Here, the constituent ratio (molar ratio) of Me, Al and P constituting the skeleton structure is usually a molar ratio of the following formulas 1-1 to 3-1, preferably the following formulas 1-2 to 3-2. If x is smaller than the above range, the amount of adsorption in the region where the adsorbate pressure is low tends to be small or the synthesis tends to be difficult, and if it is larger than the above range, impurities tend to be mixed during synthesis. Further, if y and z are out of the above ranges, synthesis is difficult.

0 ≦ x ≦ 0.3 ... 1-1
(X represents the molar ratio of Me to the total of Me, Al, and P)
0.2 ≦ y ≦ 0.6 ... 2-1
(Y represents the molar ratio of Al to the total of Me, Al, and P)
0.3 ≦ z ≦ 0.6... 3-1.
(Z represents the molar ratio of P to the sum of Me, Al, and P)
0.01 ≦ x ≦ 0.3 ... 1-2
(X represents the molar ratio of Me to the total of Me, Al, and P)
0.3 ≦ y ≦ 0.5 ... 2-2
(Y represents the molar ratio of Al to the total of Me, Al, and P)
0.4 ≦ z ≦ 0.5 ... 3-2
(Z represents the molar ratio of P to the sum of Me, Al, and P)

  Me may be contained alone or in combination of two or more. Preferable Me (Me1, Me2) is an element belonging to the third and fourth periods of the periodic table.

  Me1 preferably has an ionic radius of 3 to 0.8 nm in a divalent state, and more preferably has an ionic radius of 0.4 to 7 nm in a divalent and tetracoordinate state. Among these, at least one element selected from Fe, Co, Mg, and Zn is preferable from the viewpoint of ease of synthesis and adsorption characteristics, and Fe is particularly preferable. Me2 is a group 4B element belonging to the third or fourth period of the periodic table, and is preferably Si.

Further, aluminophosphate compounds of the present invention, the framework density (FD) is usually, 13T / nm ³ or more 20T / nm ³ or less, preferably, 13.5T / nm ³ or more, more preferably 14T / Nm ³ or more, while 19 T / nm ³ or less is preferred. Here, T / nm ³ means a T atom existing per unit volume nm ³ (the number of elements constituting a skeleton other than oxygen per 1 nm ^{3 of} zeolite), and is a unit indicating framework density: FD. . If the amount is less than the above range, the structure tends to be unstable and the durability is lowered. On the other hand, if the range is exceeded, the adsorption capacity tends to be small and the adsorbent tends not to be used.

  The aluminophosphates of the present invention have a structure defined by the International Zeolite Association (IZA) and are AEI, AEL, AET, AFI, AFN, AFR, AFS, AFT, AFX, ATO, ATS, CHA , ERI, LEV, and VFI. Among these, AEI, AEL, AFI, CHA, and LEV are preferable, and AFI and CHA are particularly preferable from the viewpoint of adsorption characteristics and durability. The ALPOs can be used alone or in combination of two or more.

  AlPOs can be synthesized using a known method. For example, a synthesis method is described in Japanese Patent Publication No. 1-57041. An example is shown below.

  Although the synthesis method of AlPOs is not particularly limited, it is usually produced by hydrothermal synthesis after mixing an aluminum source, a phosphorus source, and a Me source such as Si and Fe as required, and a template.

  First, an aluminum source, an Me source such as an iron source or a silicon source, a phosphorus source, and a template are mixed as necessary.

  Aluminum source: The aluminum source is not particularly limited, and usually includes pseudoboehmite, aluminum isopropoxide, aluminum alkoxide such as aluminum triethoxide, aluminum hydroxide, alumina sol, sodium aluminate, etc., but pseudoboehmite is easy to handle. This is preferable because of its high reactivity.

  Me source: The heteroatom means Me in the above description of aluminophosphates, and preferably Si, Fe, Co, Mg, Zn, and the like. These Me sources are usually used in the form of inorganic acid salts such as sulfates, nitrates and phosphates, organic acid salts such as acetates and oxalates, or organic metal compounds. In some cases, a colloidal hydroxide or the like may be used.

  Silicon source: As the silicon source, fumed silica, silica sol, colloidal silica, water glass, ethyl silicate, methyl silicate and the like are used.

  Phosphorus source: Phosphoric acid is usually used as the phosphorus source, but aluminum phosphate may be used.

  Template: As a template, quaternary ammonium salts such as tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, morpholine, di-n-propylamine, tri-n-propylamine, tri-n-isopropylamine, Triethylamine, triethanolamine, piperidine, piperazine, cyclohexylamine, 2-methylpyridine, N, N-dimethylbenzylamine, N, N-diethylethanolamine, dicyclohexylamine, N, N-dimethylethanolamine, choline, N, N '-Dimethylpiperazine, 1,4-diazabicyclo (2,2,2) octane, N-methyldiethanolamine, N-methylethanolamine, N-methylpiperidine, 3-methylpiperi , N-methylcyclohexylamine, 3-methylpyridine, 4-methylpyridine, quinuclidine, N, N′-dimethyl-1,4-diazabicyclo- (2,2,2) octane ion, di-n-butylamine, neo Pentylamine, di-n-pentylamine, isopropylamine, t-butylamine, ethylenediamine, pyrrolidine, 2-imidazolidone, di-isopropyl-ethylamine, dimethylcyclohexylamine, cyclopentylamine, N-methyl-n-butylamine, hexamethyleneimine, Primary amines such as secondary amines, secondary amines, tertiary amines, and polyamines. These may be used as a mixture.

  Of these, morpholine, triethylamine, cyclohexylamine, isopropylamine, di-isopropyl-ethylamine, N-methyl-n-butylamine, and tetraethylammonium hydroxide are preferable in terms of reactivity, and are industrially cheaper morpholine and triethylamine. More preferred is cyclohexylamine. These may be used alone or in combination of two or more.

Preparation of aqueous gel:
An aqueous gel is prepared by mixing the above-mentioned aluminum source, phosphorus source, and Me source and template as required. Although the mixing order varies depending on the conditions, usually, the phosphoric acid source and the aluminum source are first mixed, and the Me source and the template are mixed therewith.

The composition of the aqueous gel related to MeAPO is expressed as a molar ratio of oxide, and 0.01 ≦ MeOx (x is 1 when Me is divalent and 1.5 when trivalent) / P ₂ O ₅ ≦ 1.5, and 0.02 ≦ MeO / P ₂ O ₅ ≦ 1.0 is preferable from the viewpoint of ease of synthesis, and 0.05 ≦ MeO / P ₂ O ₅ ≦ 0.8 is more preferable. . The ratio of P ₂ O ₅ / Al ₂ O ₃ is 0.6 or more and 1.7 or less, and 0.7 to 1.6 or less is preferable from the viewpoint of ease of synthesis, and 0.8 More preferably, it is 1.5 or less. The lower limit of the proportion of water, relative to Al ₂ O _3, is 3 or more in molar ratio, preferably 5 or more from the viewpoint of ease of synthesis, and more preferably 10 or more. The upper limit of the ratio of water is 200 or less, preferably 150 or less, and more preferably 120 or less from the viewpoint of ease of synthesis and high productivity. The pH of the aqueous gel is 4 to 10, preferably 5 to 9 and more preferably 5.5 to 8.5 from the viewpoint of ease of synthesis.

  In addition, in each aqueous gel, you may coexist components other than the above as desired. Examples of such components include hydrophilic organic solvents such as hydroxides and salts of alkali metals and alkaline earth metals, and alcohols.

Hydrothermal synthesis:
Hydrothermal synthesis is carried out by placing an aqueous gel in a pressure-resistant vessel and maintaining a predetermined temperature under stirring or standing under a self-generated pressure or a pressurized gas that does not inhibit crystallization. The hydrothermal synthesis conditions are 100 to 300 ° C, and 120 to 250 ° C is preferable and 150 to 220 ° C is more preferable from the viewpoint of ease of synthesis.

  The reaction time is 3 to 30 days, preferably 5 to 15 days, more preferably 7 to 7 days from the viewpoint of ease of synthesis. After the hydrothermal synthesis, the product is separated, washed with water, dried, and the organic substances contained are removed by a method such as firing to obtain crystalline aluminophosphates containing at least Al and P in the skeleton.

Carrier:
The carrier means a base material for adhering the adsorbent and integrating and using the adsorbent, for example, paper, sheet, plate, fiber, resin, granule Etc. The shape of the carrier to which the adsorbent is fixed, that is, the shape in the case of constituting an element, is a honeycomb shape such as a sheet shape, a flat plate shape, a fin shape, or a hole shape having a substantially triangular, substantially square, or substantially hexagonal shape. And the like.

  Examples of the material of the carrier include metal such as aluminum, copper, and stainless steel in the case of a sheet-like, flat plate, and fin-like element. In the case of a honeycomb-like element, an inorganic or organic fibrous substance is used in addition to the metal. Aggregates, specifically ceramic fibers such as ceramic paper mainly composed of silica and alumina, glass fibers, metal fibers manufactured from metals such as Fe, Cu, Al, Cr, Ni, acrylic, polyethylene, polypropylene, Chemical fibers such as polyurethane, polyclar, nylon, rayon, vinylon, vinylidene, polyvinyl chloride, acetate, and polyester, or natural fibers such as cellulose, silk, and cotton can also be used. Carbon fiber can also be used.

  Among these, a honeycomb-like carrier that tends to increase the amount of adsorption in the high-humidity region due to the formation of mesopores by fixing the adsorbent is preferable, and the material is preferably a fibrous material, Ceramic fibers are preferred. The diameter of the ceramic fiber is usually in the range of 1 to 10 μm.

Adsorption element structure:
Examples of the structure of the adsorption element include various structures as shown in FIGS. The adsorbing element (1a) shown in FIG. 6 is an element formed in a sheet shape, and is configured by disposing an adsorbent layer (13) on the surface of a base sheet (12) as a carrier. The adsorption element (1a) can be shaped into various shapes and used for an adsorption refrigerator or a desiccant. Moreover, the adsorption element (2A) having a plate fin type structure as shown in FIG. 8 can be configured.

  The adsorbing element (2A) shown in FIG. 8 is a so-called plate fin type element, for example, a large number of adsorbing elements (1a) formed in a rectangular flat plate and a path through which a heat medium (a heating medium and a cooling medium) flows. Heat medium flow path (3). Each adsorption | suction element (1a) is arranged through a fixed minute ventilation space so that these each plate surface may become parallel and parallel. And the heat-medium flow path (3) is arrange | positioned in the state which penetrated each adsorption sheet (1a). One end of the heat medium flow path (3) is a heat medium inlet port (31), and the other end is a heat medium outlet port (32).

  The adsorbing element (1b) shown in FIG. 7 is configured by disposing an adsorbent layer (13) on the surface of the base sheet (12), similarly to the element of FIG. The adsorbing element (1b) is obtained by forming the base sheet (12) into a corrugated plate shape. For example, an adsorbing element (2B) having a corrugated fin structure as shown in FIG. 9 can be formed.

  The adsorbing element (2B) shown in FIG. 9 is a so-called corrugated fin-type element, and includes a plurality of band-shaped adsorbing elements (1b) that bend zigzag along the length direction. The adsorbing element (2B) includes an inlet header (41) to which a heat medium (a heat medium and a cold medium) is supplied, an outlet header (42) that discharges the heat medium, and a parallel and parallel space between these headers. And a plurality of straight tubular heat medium channels (4) through which the heat medium flows, and each strip-shaped adsorption element (1b) is located between the heat medium channels (4) as shown in the figure. Inserted into. Reference numerals (43) and (44) denote an inlet port for supplying the heat medium to the header and an outlet port for recovering the heat medium from the header.

  Furthermore, an adsorbing element (2C) having a honeycomb structure as shown in FIG. 10 can be formed by three-dimensionally processing a sheet-like carrier. The adsorption element (2C) is a cylindrical rotor type element that adsorbs and desorbs solute vapor and water vapor by being configured to allow ventilation from one end face to the other end face, and is applied to adsorption heat pumps and various desiccant systems. The

  The adsorbing element (2C) is constituted by a honeycomb structure having a cylindrical shape (for example, a short axis cylindrical shape) by a large number of sheet-like adsorbing elements (1) made of a fibrous carrier. Then, the suction sheet (1a) formed in a substantially corrugated plate shape and the suction sheet (1b) formed in a substantially flat plate shape are alternately arranged in a stacked state along the diametrical direction, thereby forming a substantially triangular opening shape. A large number of air-permeable cells (50) having the above are provided on the end face. That is, the adsorbing element (2C) is formed by laminating a plurality of honeycomb sheets around the central axis by forming a row of cells (50) by superposing the corrugated adsorbing elements (1b) on the flat adsorbing elements (1a). It has a structured. Note that the symbol (X) indicates the arrangement direction of the cells (50).

  The honeycomb in the adsorbing element (2C) is usually obtained by alternately laminating or winding a corrugated sheet obtained by corrugating a ceramic sheet obtained by mixing ceramic fibers and pulp, and a flat sheet. The honeycomb thus obtained has a small pressure loss because it has straight holes in the gas flow direction. The cross-sectional shape is substantially triangular, and the pitch is preferably 1 to 4 mm and the wave height is preferably 1.5 to 5 mm, more preferably the pitch is 1.5 to 3.5 mm and the wave height is in the range of 2 to 4 mm. . When the pitch is less than 1 mm and the wave height is less than 1.5 mm, the gas vents of the honeycomb are small, which is disadvantageous because the pressure loss increases. When the pitch exceeds 4 mm and the wave height exceeds 5 mm, the contact efficiency is deteriorated, and as a result, the dehumidifying performance may be deteriorated.

  In the case of a honeycomb rotor used in a desiccant air conditioner, the outer diameter of the disc-shaped ceramic honeycomb having honeycomb holes parallel to the rotation axis is usually 10 to 450 cm, and the length in the flow direction is preferably 2 to 50 cm. More preferably has an outer diameter of 20 to 300 cm and a length in the flow direction of 5 to 40 cm.

  The binder for fixing the adsorbent may be either an organic or inorganic binder. For example, the organic binder may be an acrylic resin, a vinyl acetate resin, a styrene resin, various copolymer resins, or an olefin resin. Resin, epoxy resin, urethane resin, phenol resin, adhesive in which resin components such as silicone resin are dissolved in organic solvent, or acrylic resin emulsion, vinyl acetate resin emulsion, styrene resin emulsion, various copolymer resin emulsions, Examples thereof include emulsion adhesives obtained by emulsifying resin components such as olefin resin emulsions, epoxy resin emulsions, urethane resin emulsions, and phenol resin emulsions. Examples of the inorganic binder include silica sol, alumina sol, titania sol, and zirconia sol. To these, a fibrous material such as a metal fiber having good thermal conductivity, carbon fiber, a metal powder such as aluminum, copper, silver, or graphite may be added. Among these, as the binder for fixing the adsorbent, an inorganic binder is preferable because it easily forms mesopores. From the viewpoint of making mesopores easier to form, silica sol is more preferable.

  In addition, addition of clay and fibrous inorganic compounds such as sepiolite and imogolite is also effective for improving the adhesion and increasing the amount of adsorption in a high humidity region due to the formation of mesopores. Among these, in the case of fixing to a honeycomb-shaped carrier, an inorganic binder is preferable because mesopores are more easily generated. Of these, silica sol is preferred.

Adsorption element manufacturing:
The production method of the adsorption element is not particularly limited as long as the produced element satisfies the adsorption performance of the present invention. After the carrier is attached by a method such as immersing it in the aqueous dispersion, it is produced by drying or baking. Of these, the method of immersing the carrier in the aqueous dispersion is preferable because it easily produces mesopores.

  Other substances such as a stabilizer may be added to the aqueous dispersion to such an extent that the effects of the present invention are not impaired. The mixing ratio of the three components in the aqueous dispersion is usually in the range of 5 to 60% by weight of the adsorbent, 0.1 to 50% by weight of the binder, and 30 to 94.9% by weight of the solvent. Preferably, the adsorbent is 10 to 45% by weight, the binder is 1 to 30% by weight, and the solvent is 40 to 80% by weight. Furthermore, the weight ratio of the solvent to the adsorbent is usually in the range of 1 to 20%, preferably 1.25 to 5%, and it is preferable that the amount of the binder does not exceed the amount of the adsorbent.

  The solid content weight of the adsorbent and the binder in the aqueous dispersion is usually 20 to 50% by weight, and the ratio of the binder solid content to the adsorbent is preferably 0.05 to 1, more preferably the solid content is 25 to 45% by weight. The binder ratio is in the range of 0.1 to 0.6. When the solid content weight is less than 20% by weight, the dehumidifying performance may be insufficient. When the solid content weight exceeds 50% by weight, there is a possibility that the honeycomb pores are blocked due to difficulty in carrying and the pressure loss increases. When the ratio of the binder solid content to the adsorbent is less than 0.05, the adsorbent may be peeled off. When the ratio of the binder solid content exceeds 0.6, the dehumidifying performance may be deteriorated.

  A drying temperature is 50-140 degreeC normally, Preferably it is 90-140 degreeC. In the case of baking, it is 200-700 degreeC, Preferably it is 300-600 degreeC.

The basis weight of the adsorbent is usually ^{30 to} 250 kg / m ³ and 20 to 900 g / kg with respect to the adsorbing element, preferably 40 to 180 kg / m ³ , which is a basis weight that easily forms mesopores, and 30-600 g / kg.

  If the basis weight is too small, a sufficient amount of adsorption cannot be obtained. When the amount is too large, mesopores are not easily formed, and clogging or resistance occurs in the ventilation of water vapor or processing air, resulting in insufficient performance.

Production Example 1:
Synthesis of FAPO-5:
To a mixture of 38 g of water and 17.5 g of 85% phosphoric acid, 9.5 g of pseudoboehmite (containing 25% water, manufactured by Sasol) was added and stirred. This was stirred for 3 hours, and an aqueous solution in which 6.78 g of ferrous sulfate heptahydrate was dissolved in 37 g of water was added thereto, and further 10.8 g of triethylamine was mixed and stirred for 3 hours to obtain a starting reaction mixture. It was. This was charged into a 200 cc stainless steel autoclave containing a Teflon (registered trademark) inner cylinder and allowed to react at 190 ° C. for 10 hours in a stationary state. After the reaction, the reaction mixture was cooled, the supernatant was removed by decantation, and the precipitate was collected. The precipitate was washed three times with water and dried in an oven at 100 ° C. Then, it was pulverized to an average of 5 microns by a dry method. 3 g of the template-containing sample thus obtained was put in a vertical quartz tube, heated to 550 ° C. at 1 ° C./min in a nitrogen stream containing 5 vol% oxygen at 200 ml / min, and kept at 550 ° C. for 6 hours. Baked.

  The XRD (using Cu—Kα rays) of the crystalline iron aluminophosphate thus obtained was measured. As a result, it was AFI type FAPO-5. In addition, when elemental analysis was performed by ICP analysis after heating and dissolving in an aqueous hydrochloric acid solution, the constituent ratio (molar ratio) of each component with respect to the total of Al, P, and Fe in the skeleton structure was Fe / Al / P = 4. It was 2 / 46.6 / 49.2%.

Production Example 2:
Synthesis of SAPO-34:
To 130 g of water, 65.5 g of 85% phosphoric acid was added, and 43 g of pseudoboehmite (containing 25% water, manufactured by Sasol) was slowly added thereto, followed by stirring for 3 hours. This is A liquid. Separately, a liquid in which 3.8 g of fumed silica (Aerosil 200), 27.5 g of morpholine, 32.1 g of triethylamine, and 185 g of water were prepared. This was slowly added to the liquid A with stirring. This was further stirred for 3 hours. This mixture was charged into a 1 L stainless steel autoclave containing a Teflon (registered trademark) inner cylinder and reacted at 190 ° C. for 48 hours while stirring at 300 rpm. After the reaction, the reaction mixture was cooled and the supernatant was removed by decantation to collect a precipitate. Thereafter, it was washed with water and dried at 100 ° C. Thereafter, it was pulverized to an average of 6 microns by a dry method.

  3 g of the template-containing sample thus obtained was placed in a vertical quartz tube, heated to 550 ° C. at 1 ° C./min in an air stream of 100 ml / min, and baked at 550 ° C. for 6 hours. The XRD (using Cu—Kα ray) of the crystalline silicoaluminophosphate thus obtained was measured. As a result, it was found to be CHA type SAPO-34. In addition, when elemental analysis was performed by ICP analysis after heating and dissolving in an aqueous hydrochloric acid solution, the composition ratio (molar ratio) of each component with respect to the total of Al, P, and Si in the skeletal structure was Si / Al / P = 8. It was 2 / 49.8 / 42.0%.

Production Example 3:
Synthesis of AIPO-5:
To a mixture of 38 g of water and 17.5 g of 85% phosphoric acid, 10.3 g of pseudoboehmite (containing 25% water, manufactured by Sasol) was added and stirred. The mixture was stirred for 3 hours, 37 g of water was added thereto, 6.8 g of triethylamine was further mixed, and the mixture was stirred for 3 hours to obtain a starting reaction mixture. This was charged into a 200 cc stainless steel autoclave containing a Teflon (registered trademark) inner cylinder and allowed to react at 190 ° C. for 12 hours in a stationary state. After the reaction, the reaction mixture was cooled, the supernatant was removed by decantation, and the precipitate was collected. The precipitate was washed three times with water and dried in an oven at 100 ° C. Then, it was pulverized to an average of 5 microns by a dry method. 3 g of the template-containing sample thus obtained was placed in a vertical quartz tube, heated to 550 ° C. at a rate of 1 ° C./min in a nitrogen stream containing 5 vol% oxygen at 200 ml / min, and 550 Baked at 6 ° C. for 6 hours.

  The XRD (using Cu—Kα rays) of the crystalline iron aluminophosphate thus obtained was measured. As a result, it was AFI type AIPO-5.

Example 1:
A slurry was prepared by mixing 40 g of FAPO-5 having an average particle diameter of 5 μm, 85.7 g of catalyst sol Cataloid S-20L (20 wt% as SiO ₂ ) and 17.2 g of water as a binder.

  The honeycomb carrying the adsorbent has a size of 50 mm in length, 50 mm in width, 10 mm in height, and is laminated by corrugating using ceramic fiber sheets to have a substantially triangular hole with a pitch of 3.4 mm and a wave height of 2.0 mm. .

This honeycomb was immersed in the water slurry, and then pulled up to drain the liquid and impregnated with FAPO-5. This was placed in an oven at 140 ° C. for 120 minutes and dried to produce an adsorbing element. From the weight measurement, the content of FAPO-5 was 406 g / kg with respect to the adsorption element. The weight per volume is 99.3 kg / m ³ .

  A portion of this adsorbing element was cut into a square of about 5 mm, and the water vapor adsorption isotherm at 25 ° C. was measured. The adsorption isotherm is measured using “Bellethorpe 18” (trade name), which is a volumetric apparatus manufactured by Nippon Bell Co., Ltd., and pretreatment is performed at a temperature of 120 ° C. for 5 hours under a vacuum condition of 5 Pa or less. Then, in an air thermostat at 50 ° C., the adsorption temperature was 25 ° C., the initial introduction pressure was 3 torr, the saturated vapor pressure was 23.755 torr, and the equilibrium time was 500 seconds. The result is shown in FIG.

  The adsorption amount difference between the relative humidity 0.7 and 0.9 per weight of the adsorption element determined from the adsorption isotherm is 0.068 g / g, and the adsorption amount difference between the relative humidity 0.72 and 0.9 is 0.00. 063 g / g, the adsorption amount difference between 0.05 and 0.28 relative humidity is 0.079 g / g, and the adsorption amount difference between 0.07 and 0.28 relative humidity is 0.076 g / g.

Example 2:
A slurry was prepared by mixing 40 g of SAPO-34 having an average particle size of 6 μm, 107.7 g of silica sol Cataloid S-20L (20 wt% as SiO ₂ ) and 10 g of water as a binder.

The same ceramic honeycomb as in Example 1 was dipped in this water slurry, then pulled up, drained, and impregnated with SAPO-34. This was placed in an oven at 140 ° C. for 120 minutes and dried to produce an adsorbing element. From the weight measurement, the content of SAPO-34 was 350 g / kg with respect to the adsorption element. The weight per volume is 76.2 kg / m ³ .

  For a part of this adsorption element, the adsorption isotherm of water vapor at 25 ° C. was measured in the same manner as in Example 1. The result is shown in FIG. Thus, the adsorption amount difference between the relative humidity 0.7 and 0.9 per weight of the adsorption element is 0.062 g / g, and the adsorption amount difference between the relative humidity 0.72 and 0.9 is 0.060 g / g. Yes, the difference in adsorption amount between 0.05 and 0.28 relative humidity is 0.083 g / g, and the difference in adsorption amount between 0.07 and 0.28 relative humidity is 0.069 g / g.

Example 3:
A slurry was prepared by mixing 40 g of AIPO-5 having an average particle size of 5 μm, 107.7 g of silica sol Cataloid S-20L (20 wt% as SiO ₂ ) as a binder, and 10 g of water.

The same ceramic honeycomb as in Example 1 was immersed in this water slurry, then pulled up, drained, and impregnated with AIPO-5. This was placed in an oven at 140 ° C. for 120 minutes and dried to produce an adsorbing element. From the weight measurement, the AIPO-5 content was 380 g / kg with respect to the adsorption element. The weight per volume is 93.2 kg / m ³ .

  For a part of this adsorption element, the adsorption isotherm of water vapor at 25 ° C. was measured in the same manner as in Example 1. The result is shown in FIG. As a result, the adsorption amount difference between 0.7 and 0.9 relative humidity per weight of the adsorption element is 0.070 g / g, and the adsorption amount difference between 0.72 and 0.9 relative humidity is 0.060 g / g. Yes, the difference in adsorption amount between 0.05 and 0.28 relative humidity is 0.072 g / g, and the difference in adsorption amount between 0.07 and 0.28 relative humidity is 0.069 g / g.

Comparative Example 1:
40 g of commercially available Y-type aluminosilicate zeolite (silica alumina ratio 5) having an average particle size of 1 μm, 107.7 g of silica sol Cataloid S-20L (20 wt% as SiO ₂ ) as catalyst as catalyst, water A slurry mixed with 10 g was prepared.

The same ceramic honeycomb as in Example 1 was immersed in this water slurry, then pulled up, drained, and impregnated with Y zeolite. This was placed in an oven at 140 ° C. for 120 minutes and dried to produce an adsorbing element. From the weight measurement, the content of Y zeolite was 348 g / kg with respect to the adsorption element. The weight per volume is 75.8 kg / m ³ .

  For a part of this adsorption element, the adsorption isotherm of water vapor at 25 ° C. was measured in the same manner as in Example 1. The result is shown in FIG. Thus, the adsorption amount difference between 0.7 and 0.9 relative humidity per weight of the adsorption element is 0.047 g / g, and the adsorption amount difference between 0.72 and 0.9 relative humidity is 0.044 g / g. Yes, the difference in adsorption amount between 0.05 and 0.28 relative humidity is 0.030 g / g, and the difference in adsorption amount between 0.07 and 0.28 relative humidity is 0.022 g / g. It can be seen that the amount of adsorption on the wet side is insufficient.

Comparative Example 2:
(Silica element)
The same ceramic honeycomb as in Example 1 was dipped in an aqueous solution of sodium silicate (No. 3), then pulled up, drained, washed with water, dried at 150 ° C. and impregnated with silica to produce an adsorbing element. The content of silica was 420 g / kg with respect to the adsorption element. The weight per volume was 88 kg / m ³ .

  For a part of this adsorption element, the adsorption isotherm of water vapor at 25 ° C. was measured in the same manner as in Example 1. The result is shown in FIG. Thereby, the adsorption amount difference between the relative humidity 0.7 and 0.9 per weight of the adsorption element is 0.025 g / g, and the adsorption amount difference between the relative humidity 0.72 and 0.9 is 0.024 g / g. Yes, the difference in adsorption amount between 0.05 and 0.28 relative humidity is 0.041 g / g, and the difference in adsorption amount between 0.07 and 0.28 relative humidity is 0.036 g / g. It can be seen that the amount of adsorption on the wet side is insufficient.

Dehumidification experiment:
The dehumidification performance of the rotor (adsorption element) supporting FAPO-5 of Example 1 and the rotor (adsorption element) supporting silica of Example 2 were compared in a low humidity environment and a high humidity environment.

Example 4:
Creation of FAPO-5 rotor:
As in Example 1, the ceramic fiber sheet was corrugated so as to form a substantially triangular hole having a pitch of 3.4 mm and a wave height of 2.0 mm, and this was wound to form a disk-shaped honeycomb. This honeycomb was impregnated with FAPO-5 in the same manner as in Example 1 and post-treated to prepare a FAPO-5 rotor. The size of the honeycomb is 300 mm in diameter, 44 mm in inner diameter, and 200 mm in thickness. The content of FAPO-5 was 300 g / kg with respect to the rotor, and the weight per volume was 75 kg / m ³ .

Comparative Example 3:
Creating a silica rotor:
As in Example 1, the ceramic fiber sheet was corrugated so as to form a substantially triangular hole having a pitch of 3.4 mm and a wave height of 2.0 mm, and this was wound to form a disk-shaped honeycomb. Next, gelation was performed after impregnating with sodium silicate aqueous solution and draining the solution. After the treatment, it was thoroughly washed with water and dried at 150 ° C. The obtained silica rotor has a honeycomb portion with a diameter of 300 mm, an inner diameter of 44 mm, and a thickness of 200 mm. The content of silica gel was 480 g / kg, and the weight per volume was 100 kg / m ³ .

Dehumidification experiment method:
Using a dehumidifying device having a rotor, a dehumidifying amount G represented by the following equation was obtained. This measurement was performed after adsorption and desorption were sufficiently repeated after 1 hour from the start of operation of the apparatus, and after the treatment, the absolute humidity at the outlet of the tank did not change stably. The rotational speed of the rotor was 24 rpm. The following table shows the low humidity environment conditions and high humidity environment conditions that are measurement conditions. As a result of the measurement, the results shown in the following table were obtained.

2 is a water vapor adsorption isotherm of the adsorption element obtained in Example 1. FIG. 4 is a water vapor adsorption isotherm of the adsorption element obtained in Example 2. FIG. 6 is a water vapor adsorption isotherm of the adsorption element obtained in Example 3. FIG. 4 is a water vapor adsorption isotherm of the adsorption element obtained in Comparative Example 1. FIG. 4 is a water vapor adsorption isotherm of the adsorption element obtained in Comparative Example 2. It is a partial perspective view which shows the sheet-like adsorption element which is one form of the adsorption element of this invention. It is a partial perspective view which shows the sheet-like adsorption | suction element which is the other form of the adsorption | suction element of this invention. It is a perspective view which shows the plate fin type adsorption | suction element which is another form of the adsorption | suction element of this invention. It is a perspective view which shows the corrugated fin type adsorption | suction element which is another form of the adsorption | suction element of this invention. FIG. 6 is a perspective view showing a rotor type adsorption element having a cylindrical honeycomb structure, which is still another embodiment of the adsorption element of the present invention, and a partially enlarged view showing a cell shape.

DESCRIPTION OF SYMBOLS 1: Adsorption element 1a: Adsorption element 1b: Adsorption element 12: Base material sheet 13: Adsorbent material layer 2A: Adsorption element 2B: Adsorption element 2C: Adsorption element 3: Heat medium flow path 4: Heat medium flow path 41: Inlet side Header 42: Exit side header 50: Cell

Claims (7)

  An adsorption element in which an adsorbent is fixed to a carrier with a binder, and a difference between an adsorption amount at a relative humidity of 90% and an adsorption amount at a relative humidity of 70% on an adsorption isotherm at 25 ° C. is 0.05 g / g or more. And the difference between the adsorption amount at a relative humidity of 5% and the adsorption amount at a relative humidity of 28% is 0.05 g / g or more.   The adsorptive element according to claim 1, wherein the adsorbent is a crystalline aluminophosphate containing at least Al and P in the skeleton structure.   The adsorption element according to claim 1 or 2, wherein the carrier is a fibrous substance.   The adsorption element according to claim 1, wherein the carrier is a ceramic fiber.   The adsorption element according to claim 1, wherein the binder is an inorganic binder.   The adsorbing element according to claim 1, wherein the adsorbing element has a honeycomb shape.   A humidity control air conditioner using the adsorbing element according to claim 1.

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