KR101742293B1 - Hierarchical nano porous aluminophosphate having excellent moisture absorption and Manufacturing method thereof - Google Patents

Abstract

The present invention relates to a moisture adsorbent prepared by adsorbing an inorganic salt to a hierarchical nano-porous aluminophosphate containing micropores and mesopores, and more particularly, to a water adsorbent prepared by adsorbing inorganic nanoporous aluminophosphates having a high pore volume and an inorganic salt, The present invention relates to a porous aluminophosphate and a method for producing the porous aluminophosphate and a method for producing the porous aluminophosphate. More particularly, the present invention relates to porous aluminophosphates and mesoporous aluminophosphates, It can exhibit a high moisture adsorption performance. In addition, it can provide an adsorbent which can be used in an adsorption refrigerator suitable for weather conditions in Korea by showing a high moisture adsorption performance at 30 ~ 35 ° C and a relative humidity of 0.1 ~ 0.3 (0.56 ~ 1.68 kPa), which is a summer condition in Korea.

Description

[0001] Hierarchical nano-porous aluminophosphate having excellent water adsorption property and a method for producing the same [0002]

The present invention relates to a moisture adsorbent prepared by adsorbing an inorganic salt to a hierarchical nano-porous aluminophosphate containing micropores and mesopores. The present invention relates to a moisture adsorbent prepared by adsorbing inorganic nanoporous aluminophosphates having a high pore volume and an inorganic salt, Porous aluminophosphates and processes for their preparation.

In recent years, efficient use of energy has become a big issue worldwide for the increase of energy demand and response to climate change. Especially, the technology to efficiently utilize various industrial waste heat (60 ~ 90 ℃) There is a lot of interest.

In particular, efforts are being made to find ways to effectively utilize the new and renewable thermal energy in the summer season. One of them is the use of new and renewable heat energy in a refrigerator with a very high usage in the summer have.

Due to recent economic developments, demand for cooling has increased sharply due to the pursuit of comfortable residential and working environment and the warming due to global warming. 15% of the world's electricity and 45% of the total domestic and commercial buildings are cooled and cooled The absorption refrigerating system can be a way to increase the utilization of waste heat energy and renewable heat energy.

The adsorption refrigeration system is generally operated at a low temperature (60 to 90 ° C) and utilizes natural refrigerants such as water, alcohol, and ammonia and adsorbents such as silica gel, zeolite, activated carbon, (-20 to 0 ° C).

The adsorption type refrigeration system utilizes heat generation and endothermic phenomena caused by the reversible reaction between the adsorbent and the refrigerant, and is a freezing heat tube that generates cold heat by using industrial waste heat or a new and renewable heat source as a heating source. As shown in FIG. 1, the system is a closed system vacuum vessel composed of an adsorption tower, a condenser, and an evaporator, each of which has a heat transfer tube, and only the adsorbent and refrigerant exist in the system. Commercial devices consist mainly of two adsorption towers to continuously produce cold heat. When one adsorption tower is connected to the evaporator and adsorption step is carried out while adsorbing the dear refrigerant, the hot water is supplied to the other tower to raise the temperature of the adsorbent to desorb the refrigerant, and then the refrigerant is moved to the condenser to condense the adsorbent Is performed.

For example, if the most environmentally friendly water is used, adsorption of water under 35 ° C, about 9.2 Torr water vapor using a specific adsorbent, and desorption of water adsorbed under 80 ° C, about 42.2 Torr water vapor, It produces cold heat of about 15 ℃.

 Nanoporous materials such as silica gel, activated carbon, zeolite, and metal-organic framework (MOF), which are substances capable of adsorbing the refrigerants, may be used.

Commercialized adsorption refrigeration systems generally use silica gel and water. The silica gel has a tendency to start adsorption at a low water vapor partial pressure due to its strong hydrophilicity, but the amount of water adsorbed per unit adsorbent in the driving pressure range (P / P ₀ = 0.1 to 0.3) on the adsorption refrigeration system is 0.08 g-water / d-sorbent so that the volume of the adsorption refrigeration system is large and the apparatus ratio is high. Also, the RD type silica gel of Fuji silysia Chemical, which is mainly used commercially, has a low moisture adsorption amount of less than 10 wt% in the relative humidity range (P / P ₀ = 0.1 ~ 0.3), which is an operating condition.

On the other hand, activated carbon widely used as a moisture adsorbent exhibits various amounts of water adsorption depending on the specific production method and raw material components. In the case of general activated carbon, the moisture adsorption amount is very low at a relative humidity (P / P ₀ ) / P ₀ ) 0.5 or more, the amount of moisture adsorption increases sharply and the maximum adsorption amount is excellent.

Similarly, in the case of mesoporous silica, the adsorption amount is higher than 60 wt% at room temperature (25 ° C.), but most of the moisture adsorption is adsorbed at a relative humidity (P / P ₀ ) of 0.5 or more.

On the other hand, in the case of zeolite having the structure of FAU (Faujasite) and LTA (Linde Type A), the maximum moisture adsorption characteristic is 22 to 35 wt% at a room temperature (25 ° C.) There is a very high problem.

In addition, the product group of AQSOA ^TM of Mitsubishi Chemical of Japan includes aluminum and phosphorus as main components and relatively low water affinity compared to conventional zeolite materials of aluminum and silicon, and ferroaluminophosphate-5 zeolite Zeolite (FAPO ₄ -5)) was used as a moisture adsorbent. This technique partially added Fe ions in the lattice structure of AlPO ₄ -5 to increase the adsorption relative vapor pressure of the adsorbent refrigerating machine (P / Po = 0.1 ~ 0.3 ). The maximum moisture adsorption amount of AQSOA is known to adsorb less than 0.2 g of water per 1 g of AQSOA in the range of P / P ₀ = 0.1 to 0.3.

In recent years, the use of metal-organic framework (MOF) in the absorption refrigerator has been reported. In the case of MIL-101, the relative humidity (P / P ₀ ) (P / P ₀ ) of 0.4 or higher, and the operation range of the low temperature heat source driven adsorption cooling system of 90 ° C or less .

In order to improve the performance of the absorption type refrigeration system and to reduce the equipment cost, a new adsorbent having a higher water adsorption amount within the driving pressure range is required.

The registered patent No. 1544721 (Registered on Aug. 5, 2018) discloses a method for producing a water-absorbing composition, comprising the steps of preparing silica, salt and distilled water, dissolving the salt in distilled water to prepare an impregnation solution, To thereby prepare a water adsorption composition.

In the registered patent No. 0803964 (Registered on Feb. 18, 2008), it has a surface area of more than 1,700 m ² / g and a pore volume of more than 0.8 mL / g and contains both organic and inorganic materials as constituents of the skeleton. The organic-inorganic hybrid material has an adsorbent using a porous hybrid inorganic-organic material containing iron as a metal component produced through reaction of an iron precursor and an organic ligand compound capable of coordinating with an iron precursor.

However, in the case of the adsorbent using the moisture adsorbing composition or the porous organic-inorganic hybrid material shown in the above-mentioned documents, the amount of moisture adsorption is still insufficient at a relative humidity (P / P ₀ ) = 0.1-0.3.

Accordingly, while solving the problems of the conventional art, the relative humidity (P / P ₀ ) = It is required to develop a new type of adsorbent capable of easily adsorbing water at a temperature of 0.1 to 0.3 (0.56 to 1.68 kPa) at a low temperature of 90 ° C or less.

Registered Patent No. 1544721 (Registration Notice) Registration No. 0803964 (Registered on Feb. 18, 2008)

The present invention was prepared by the inorganic salt is impregnated hierarchy nanoporous aluminophosphate containing an inorganic salt in a hierarchical nano-porous alumino-phosphates, summertime conditions of our country (30 ~ 35 ℃, P / P 0 = 0.1 to 0.3 (0.56 to 1.68 kPa)) having a water adsorption property higher than that of a conventional zeolite-based nanoporous material, and having excellent water adsorbability.

In order to achieve the above-mentioned object, an embodiment of the present invention is preferably a hierarchical nano-porous aluminophosphate having a hierarchical porous structure and containing an inorganic salt in the pores and having excellent water adsorbability .

The topological pores may include mesopores and micropores, wherein the mesopores are 3.5-23 nm in diameter and may be arranged in a non-regular manner.

Further, the fine pores, having a diameter of 0.35 ~ 1.0 nm and, AFI (Aluminophosphate-five, AlPO 4 -5), AEL (Aluminophosphate-eleven, AlPO 4 -11), CHA (Chabazite), (Virgina Polytechnical Institute) VPI , And FAU (Faujasite) structures.

The inorganic salt may be selected from at least one compound selected from lithium chloride (LiCl), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl ₂ ), sodium chloride (NaCl), zinc chloride (ZnCl 2) and potassium chloride , And the inorganic salt may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the hierarchical nanoporous aluminophosphate.

In another embodiment of the present invention, there is provided a method for producing a nanoporous aluminophosphate, comprising the steps of: preparing a hierarchical nanoporous aluminophosphate; impregnating the inorganic nanoporous aluminophosphate with the inorganic salt; And a dehydration step of removing the water-containing nanoporous aluminophosphate.

The step of preparing the hierarchical nanoporous aluminophosphate may include a synthesis step of synthesizing an aluminophosphate by mixing an aluminum precursor, a phosphine precursor, a transition metal or a silicon precursor, an amine compound, a surfactant, and distilled water, And a calcination step of calcining the naphosphate to produce a hierarchical nano-porous aluminophosphate. The method may further include a drying step of filtering the synthesized aluminophosphate before the calcination step and then drying the calcined aluminophosphate.

The aluminum precursor may be at least one selected from the group consisting of pseudoboehmite, aluminum isopropoxide and aluminum hydroxide. The transition metal precursor may be at least one selected from the group consisting of iron nitrate Fe (NO ₃ ) ₃ , FeCl ₃ , Mg (NO ₃ ) ₂ , MgCl ₂ , Co (NO ₃ ) ₂ , CoCl ₂ , (Cr (NO ₃ ) ₃ ), CrCl ₃ , Ni (NO ₃ ) ₂ , NiCl ₂ , Silicasol, fumedsilica, tetra (Tetra ethoxyortho silicate), and the surfactant is preferably an organosilane surfactant. The surfactant may be at least one selected from the group consisting of tetraethoxysilane and tetraethoxyorthosilicate.

The synthesis step comprises hydrothermal synthesis at a temperature of 180 to 300 ° C for 20 to 30 hours, wherein the molar ratio of the aluminophosphate synthesized in the synthesis step is Al ₂ O ₃ : P ₂ O ₅ : Amine: H ₂ O: The transition metal salt or the silicate salt: organosilane surfactant is preferably 1: 1: 1.5 to 2.0: 100: 0.01 to 0.2: 0.01 to 0.2.

The firing step is preferably performed at 500 to 700 ° C for 1 to 3 hours.

The inorganic salt may be at least one selected from the group consisting of lithium chloride (LiCl), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl ₂ ), sodium chloride (NaCl), zinc chloride (ZnCl 2) and potassium chloride have.

The impregnation step preferably impregnates 0.1 to 5 parts by weight of the inorganic salt with respect to 100 parts by weight of the fired nanoporous porous aluminophosphate, more preferably 1 to 1.5 times the pore volume of the hierarchical nanoporous aluminophosphate The distillation water containing the inorganic salt of the ship volume may be impregnated with the above-mentioned hierarchical nanoporous aluminophosphate.

The present invention relates to a hierarchical nanoporous aluminophosphate having excellent water adsorption property and a method for producing the same, wherein a high pore volume and a hygroscopic property of an inorganic salt are simultaneously obtained by impregnating an inorganic salt into a mesoporous and micropored hierarchical nanoporous aluminophosphate It is possible to exhibit a higher water adsorption performance than other conventional porous aluminophosphates.

In addition, it can provide an adsorbent which can be used in an adsorption refrigerator suitable for weather conditions in Korea by showing a high moisture adsorption performance at 30 ~ 35 ° C and a relative humidity of 0.1 ~ 0.3 (0.56 ~ 1.68 kPa), which is a summer condition in Korea.

1 is a schematic diagram of an adsorption refrigeration system driven by a low temperature heat source to produce cold heat.
FIG. 2 is a flowchart schematically showing a method of producing a hierarchical nanoporous aluminophosphate having excellent water-adsorbability according to the present invention.
3 is a schematic view schematically showing a method of synthesizing a hierarchical nanoporous aluminophosphate having excellent water adsorption property according to the present invention.
4 is a graph showing the results of X-ray diffraction analysis of a hierarchical nanoporous aluminophosphate according to whether the inorganic salt of the present invention is impregnated or not.
5 is a graph showing the results of low-temperature nitrogen physical adsorption analysis of a hierarchical nano-porous aluminophosphate according to the presence or absence of the inorganic salt impregnation of the present invention.
FIG. 6 is a TEM photograph of a hypersensitive nanoporous aluminophosphate impregnated with the inorganic salt of the present invention (Example 3) by a projection electron microscope. FIG.
FIG. 7 is a graph showing the amounts of adsorbed moisture of nanoporous aluminophosphates (Comparative Example 1) and Comparative Examples 2 and 4 prepared by changing the amount of inorganic salt to be immersed in nanoporous aluminophosphate.
Fig. 7 is a graph showing the relationship between the amount of water adsorption of the hi-system nanoporous aluminophosphate (Comparative Example 5) and the amount of water adsorption of Examples 1 to 3 and Comparative Example 6 prepared while varying the amount of the inorganic salt of the hierarchical nanoporous aluminophosphate FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. As well as the fact that

Throughout this specification, when an element is referred to as "including" an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

The terms "first "," second ", and the like are intended to distinguish one element from another, and the scope of the right should not be limited by these terms. For example, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of the steps, and each step may be performed differently from the stated order unless clearly specified in the context. have. That is, each of the steps may be performed in the same order as described, or may be performed substantially concurrently or in the reverse order.

Hereinafter, a hierarchical nanoporous aluminophosphate having excellent water adsorption ability and a method for producing the same will be described in detail.

First, the hierarchical nanoporous aluminophosphate having excellent water-adsorptivity of the present invention may form hierarchically porous pores and may include inorganic salts in the pores.

The peristaltic pores may be mesopores or micropores, preferably pores formed step by step according to their size or size.

The diameter of the mesopores is preferably 3.5 to 25 nm, more preferably irregularly arranged, and the diameter of the micropores is preferably 0.35 to 1.0 nm, more preferably 0.7 to 1.0 nm At least one structure of AFI (Aluminophosphate-five, AlPO ₄ -5), Aluminophosphate-eleven, AlPO ₄ -11, CHA (Chabazite), VPI (Virgina Polytechnical Institute) and FAU have.

This structure was categorized by the International Zeolite Association's structural committee in accordance with the rules of the IUPAC Committee on nomenclature of zeolites. According to this classification, the framework-type zeolite and other crystalline amorphous molecular sieves for which the structure is set are assigned three letter codes and are described in Atlas of Zeolite Framing Types, 5th edition, Elsevier, London, England (2001) .

The inorganic salt contained in the micropores and / or the mesopores may be at least one selected from the group consisting of lithium chloride (LiCl), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl ₂ ), sodium chloride (NaCl), zinc chloride (ZnCl 2) At least one selected from the group consisting of

It is preferable that the inorganic salt is contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the hierarchical nano-porous aluminophosphate of the present invention. If the content of the inorganic salt is out of the above range, the pore formed in the aluminophosphate, It is possible to cause a problem that the water adsorption becomes inferior due to not using the properties at the same time.

Another embodiment of the present invention will now be described with reference to FIG. 2, which comprises the steps of preparing a hierarchical nanoporous aluminophosphate, impregnating the inorganic nanoporous aluminophosphate with an inorganic salt, And a dehydrating step of removing moisture of the aluminophosphate.

The step of preparing the hierarchical nanoporous aluminophosphate may include a synthesis step of synthesizing an aluminophosphate by mixing an aluminum precursor, a phosphine precursor, a transition metal or a silicon precursor, an amine compound, a surfactant, and distilled water, And a calcination step of calcining the naphosphate to produce a hierarchical nanoporous aluminophosphate. The method may further include a drying step of filtering and drying the synthesized aluminophosphate.

A method for producing a hierarchical nanoporous aluminophosphate having an excellent water-absorbing property according to the present invention is schematically shown in FIG. 3 and will be described in more detail with reference to FIG.

The synthesis step is a step of synthesizing aluminophosphate by mixing an aluminum precursor, a phosphine precursor, a transition metal or a silicon precursor, an amine compound, a surfactant, and distilled water. Preferably, the aluminum precursor is added to distilled water, , A phosphine precursor, an amine compound, a transition metal precursor, and a surfactant were sequentially added, and hydrothermal synthesis was performed at 180 to 300 ° C for 20 to 30 hours.

Preferably, the aluminum precursor is one of Pseudoboehmite, Aluminum isopropoxide and Aluminum hydroxide. The phosphine precursor may be any phosphorus-containing compound. Preferably, phosphoric acid can be used, and the amine compound is preferably trimethylamine.

The transition metal precursor is iron nitrate _{(Fe (NO 3) 3)} , iron chloride (FeCl _3), magnesium nitrate _{(Mg (NO 3) 2)} , magnesium chloride (MgCl _2), cobalt nitrate (Co (NO _{3) 2)} , cobalt chloride (CoCl _2), nitrate, chromium _{(Cr (NO 3) 3)} , chloride, chromium (CrCl _3), nickel nitrate _{(Ni (NO 3) 2)} , nickel chloride (NiCl _2), silica sol (Silicasol), It is preferable to use at least one selected from the group consisting of dry silicate (fumed silica) and tetra ethoxyortho silicate, and it is preferable to use an organic silane surfactant as the surfactant,

(1) H _{2n + 1} C _n NC ₃ H ₆ Si (OCH ₃ ) ₃ ⁺ Br ^- (n = an integer between 12 and 22)

Is more preferably an organosilane-based surfactant.

The synthesis is preferably carried out at 180 to 300 ° C. for 20 to 30 hours to synthesize a hierarchical nanoporous aluminophosphate. When the temperature and time are out of the range, the reaction does not proceed to obtain a porous aluminophosphate Can not be used, or there is no benefit of over-temperature and time-out.

The final molar composition ratio of the synthesis step is 1: 1: 1.5 to 2.0: 100: 0.01 to 0.2: 0.01 to 0.2 in Al ₂ O ₃ : P ₂ O ₅ : Amine: H ₂ O: transition metal: organosilane surfactant . When the molar composition ratio is exceeded, aluminophosphate having a crystal structure other than the desired crystal structure may be synthesized or amorphous aluminophosphate may be synthesized.

In the drying step after filtration to obtain the aluminophosphate synthesized through the synthesis step, the solution reacted in the synthesis step is preferably filtered, washed with distilled water, dried at 80 to 150 ° C can do.

And the calcined aluminophosphate is calcined at a temperature ranging from 500 to 700 ° C for 1 to 3 hours to produce a hydrogenated aluminophosphate.

The hysteretic nanoporous aluminophosphate produced through the firing step is preferably formed with a hierarchical pore containing micropores and mesopores. The detailed description of the above-mentioned micro pores and the hierarchical pores including the mesopores is omitted because they are mentioned above.

The impregnation step of impregnating the inorganic nanoporous aluminophosphate with the inorganic nanoporous aluminophosphate may be carried out by any known method of impregnating inorganic nanoparticles with the inorganic nanoparticles of the nanoporous aluminophosphate, Incipient wetness impregnation can be used.

More preferably, the hydrogenated nanoporous aluminophosphate can be impregnated into distilled water containing inorganic salt having a volume of 1 to 1.5 times the pore volume of the above-mentioned hierarchical nanoporous aluminophosphate, and when it is out of the above volume range, The inorganic salt may not be sufficiently impregnated into the nanoporous aluminophosphate, or rather the inorganic salt may block the pore to lower the water adsorbability.

At this time, the inorganic salt may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the calcined hierarchical nano-porous aluminophosphate.

The inorganic salt is at least one selected from the group consisting of lithium chloride (LiCl), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl ₂ ), sodium chloride (NaCl), zinc chloride (ZnCl 2) and potassium chloride desirable.

Hereinafter, an embodiment of the present invention will be described. However, the scope of the present invention is not limited to the following preferred embodiments, and a person skilled in the art can carry out various modifications of the contents described in the present invention within the scope of the present invention.

[Comparative Example]

Nanoporous Aluminophosphate (FAPO ₄ -5) of  Produce

To a solution of 41.2 g of phosphoric acid in 76 g of water, 24.2 g of triethylamine (triethylamine) was added and stirred vigorously for 30 minutes. The vessel of the stirred solution was immersed in ice water and the temperature was lowered. 81.8 g of aluminum isopropoxide was slowly added thereto while stirring vigorously. 1.6 g of iron chloride (II) · tetrahydrate (Iron Chloride (II) · Tetrahydrate) was added to the well-mixed solution, stirred for 2 hours so that the iron was well dispersed, transferred to an autoclave, And the hydrothermal synthesis was carried out for 7 hours. After 7 hours, the reaction was terminated by raising the temperature to room temperature. The product was washed three times with distilled water, dried at 150 ° C for 1 hour, heated to 550 ° C and calcined for 5 hours. The final product was Comparative Example 1, a nanoporous aluminophosphate in the form of a light ocher solid powder.

Comparative Example 1 is composed of Al ₂ O ₃ : P ₂ O ₅ : FeO: TEA: H ₂ O = 1: 1.05: 0.1: 1.2: 50 molar ratio.

CaCl ₂ was added to 1 g of distilled water according to the following Table 2 to completely dissolve the CaCl ₂ aqueous solution and then the aqueous CaCl ₂ solution was uniformly mixed with 2 g of the nanoporous aluminophosphate of Comparative Example 1 And then dried at 80 DEG C for 2 hours to prepare Comparative Examples 2 to 4, which are nanoporous aluminophosphates impregnated with an inorganic salt.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 CaCl ₂ (g)
(Parts by weight) -
- 0.67
(33 parts by weight) One
(50 parts by weight) 2
(100 parts by weight)

[Example]

Inorganic salts Impregnated  Hierarchical nanoporosity Aluminophosphate  Produce

10.2 g of aluminum isopropoxide was added to 40 g of distilled water and stirred for about 2 hours, and 5.76 g of phosphoric acid was slowly added to the aqueous solution. After the phosphoric acid was added, the mixture was stirred for 1 hour, 4.05 g of trimethylamine was slowly added thereto, and the mixture was stirred for another 30 minutes.

A solution obtained by dissolving 1.01 g of iron nitrate (Fe (NO ₃ ) ₃ ) in 3.74 g of distilled water was slowly added to the aqueous solution containing trimethylamine and stirred for 30 minutes. Then, an organosilane solution (H ₃₄ C ₁₆ NC _{3 H 6 Si (OCH 3) 3} - to _{^{Br +, 60 wt% CH 3}} OH) 2 g in a slowly to the aqueous solution to prepare a mixed solution and stirred for additional 30 minutes.

The mixed solution was put into a stainless steel high pressure reactor which had been treated with Teflon material, and then placed in an oven at 200 ° C. for 24 hours to conduct a hydrothermal synthesis reaction.

After 24 hours, the hydrolysis-synthesized synthesis solution was cooled and filtered to obtain a solid product. The obtained product was dried at 100 ° C for about one hour and then calcined at 550 ° C for 2 hours to obtain a hydrogen peroxide-type nanoporous aluminophosphate (Comparative Example 5).

CaCl ₂ was added to 1 g of distilled water according to the following Table 1 to completely dissolve the CaCl ₂ solution to prepare a CaCl ₂ aqueous solution. Then, a simple deposition method was used to uniformly infiltrate the CaCl ₂ aqueous solution into 2 g of the prepared nanoporous aluminophosphate And then dried at 80 ° C for 2 hours to prepare Examples 1 to 3 and Comparative Example 6, which are inorganic nanoporous aluminophosphates impregnated with an inorganic salt.

Comparative Example 5 Example 1 Example 2 Example 3 Comparative Example 6 CaCl ₂ (g)
(Parts by weight) -
- 0.01
(0.5 parts by weight) 0.06
(3 parts by weight) 0.1
(5 parts by weight) One
(10 parts by weight)

[Experimental Example 1]

Inorganic salt Impregnation  Characterization by presence or absence

The structure was analyzed using X-ray diffraction for the inorganic nanoporous aluminophosphate impregnated with the inorganic salt of Example 3 and the nanoporous porous aluminophosphate of Comparative Example 5 prepared through the above examples.

Also, the pore size and specific surface area of the Example 3 and Comparative Example 5 were measured by the nitrogen physical adsorption method, and the permeation electron microscope was used to confirm the arrangement of the pores and impregnation of the inorganic salt in Example 3.

Referring to FIG. 4, it can be confirmed that the material is an aluminophosphate material having crystalline AFI (Aluminiumphosphate-five, AlPO ₄ -5) structure. In addition, there was no significant difference in the structures of Comparative Example 5 and Example 3 after the impregnation of the inorganic salt CaCl ₂ , and it was found that the CaCl ₂ was impregnated with the hierarchical nanoporous aluminophosphate in an amorphous state.

5, mesopores of 0.04 cc g ^-1 and 0.20 cc g ^-1 were formed in Comparative Example 5 measured by nitrogen physical adsorption, and the specific surface area of BET (Brunauer, Emmett and Teller) was 183 m ² g ^-1 . In Example 3, it was confirmed that the microspheres of about 0.03 ccg ^{-1 and} the mesopores of 0.08 ccg ^-1 were reduced due to the impregnation with CaCl ₂ , which is an inorganic salt.

In case of Example 3, as shown in FIG. 5, when observed using a transmission electron microscope, aluminophosphate particles of 5 to 10 nm diameter having micropores arranged with regular regularity were arranged, Mesopores were formed between the aluminophosphate particles and CaCl ₂ salt was uniformly dispersed among the aluminophosphate particles.

[Experimental Example 2]

Moisture adsorption property analysis

100 mg of each of the above Comparative Examples 1 to 6 and Examples 1 to 3 was dehydrated in a vacuum state at 150 캜 for 6 hours, then lowered to 35 캜, and under the steam of the same temperature and relative humidity (P / P ₀ ) 0 to 1.0 The increase in water adsorption amount was measured.

FIG. 7 is a graph showing the amounts of adsorbed moisture of nanoporous aluminophosphate (Comparative Example 1) formed only with micropores and Comparative Examples 2 and 4 prepared by changing the amount of inorganic salt to be impregnated in nanoporous aluminophosphate, In the case of Example 1, it was confirmed that as the relative humidity (P / P _o ) increases, the amount of water adsorption gradually increases. In Comparative Example 2, in which nanoporous aluminophosphate (FAPO ₄ -5) (P / P _o ) between 0.05 and 0.3 as the impregnation amount of the inorganic salt increases, but in Comparative Example 4, since the inorganic salt is excessively impregnated and the volume of the micropores is reduced It was confirmed that the amount of moisture adsorption was reduced.

8 is a graph showing moisture adsorption amounts of Comparative Examples 5 and 6 and Examples 1 to 3. It was confirmed that the moisture adsorption amount of Comparative Example 5 was increased compared to Comparative Example 1 in which only fine pores were formed, in the case of the inorganic salts in the furnace phosphate which examples 1 to 3 was impregnated RH (P / P _o) of 0.05 in the water absorption is hardly take place, relative humidity (P / P _o) increased the amount of 0.05 to 0.3 the inorganic salt impregnated It was confirmed that the adsorption amount rapidly increased to about 300 mg / g.

In addition, in Comparative Examples 2 and 3 in which the microporosity-formed aluminophosphate was impregnated with an inorganic salt, the amounts of adsorption of water in Examples 1 to 3 of the present invention were compared, I could confirm.

In Comparative Example 6 in which the inorganic nanoporous aluminophosphate was impregnated with 100 parts by weight of inorganic nanoparticles, it was confirmed that the inorganic nanoparticles were in the form of blocking the pores and the amount of water adsorption was reduced as compared with Example 3.

Hence, the present invention provides a high-performance nanoporous aluminophosphate having an excellent water-adsorbing property and a high pore volume due to mesopores and micropores and a hygroscopic property of an inorganic salt, thereby exhibiting a higher water adsorption performance than other porous aluminophosphates I could confirm.

Claims (20)

delete delete delete delete delete delete delete delete Fabricating a hierarchical nanoporous aluminophosphate having a hierarchically porous formed stepwise or multi-stepwise according to size;
Impregnating the inorganic nanoporous aluminophosphate with the inorganic nanoparticles; And
And a dehydrating step of removing water from the inorganic nanoporous aluminophosphate impregnated with the inorganic salt,
Wherein the step of preparing the hierarchical nanoporous aluminophosphate comprises:
A synthesis step of synthesizing an aluminophosphate by mixing an aluminum precursor, a phosphine precursor, a transition metal or a silicon precursor, an amine compound, a surfactant, and distilled water; And
And calcining the synthesized aluminophosphate to produce a hierarchical nanoporous aluminophosphate,
The molar ratio of the aluminophosphate synthesized in the synthesis step is 1: 1: 1.5 to 2.0: 100: Al ₂ O ₃ : P ₂ O ₅ : Amine: H ₂ O: transition metal salt or silicate: 0.01 to 0.2: 0.01 to 0.2,
Wherein the impregnating step comprises impregnating 0.1 to 5 parts by weight of an inorganic salt with respect to 100 parts by weight of the fired nanoporous porous aluminophosphate. delete 10. The method of claim 9,
And a drying step of filtering the synthesized aluminophosphate and drying the synthesized aluminophosphate before the firing step. The method of producing a hierarchical nanoporous aluminophosphate excellent in water adsorbability. 10. The method of claim 9,
Wherein the aluminum precursor is at least one selected from the group consisting of pseudoboehmite, aluminum isopropoxide and aluminum hydroxide. The aluminum precursor may be at least one selected from the group consisting of pseudoboehmite, aluminum isopropoxide, aluminum hydroxide, Gt; 10. The method of claim 9,
The transition metal precursor, iron nitrate _{(Fe (NO 3) 3)} , iron chloride (FeCl _3), magnesium nitrate _{(Mg (NO 3) 2)} , magnesium chloride (MgCl _2), cobalt nitrate (Co (NO _{3) 2} ), Cobalt chloride (CoCl ₂ ), chromium nitrate (Cr (NO ₃ ) ₃ ), chromium chloride (CrCl ₃ ), nickel nitrate (Ni (NO ₃ ) ₂ ), nickel chloride (NiCl ₂ ), silica sol Wherein the at least one member selected from the group consisting of silica, fumed silica, and tetra ethoxyortho silicate is at least one selected from the group consisting of silica, alumina, zirconia, and silica. 10. The method of claim 9,
Wherein the surfactant is an organosilane-based surfactant. 2. The method of claim 1, wherein the surfactant is an organosilane-based surfactant. 10. The method of claim 9,
Wherein the synthesis step comprises hydrothermal synthesis at a temperature of 180 to 300 ° C for 20 to 30 hours, and a method of producing a hierarchical nanoporous aluminophosphate excellent in water adsorption. delete 10. The method of claim 9,
Wherein the calcining step is performed at a temperature of 500 to 700 ° C for 1 to 3 hours. 10. The method of claim 9,
The inorganic salt is at least one selected from the group consisting of lithium chloride (LiCl), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl ₂ ), sodium chloride (NaCl), zinc chloride (ZnCl 2) and potassium chloride By weight based on the total weight of the hydrous aluminophosphate. delete 10. The method of claim 9,
The impregnating step may include a step of impregnating distilled water containing an inorganic salt having a pore volume of 1 to 1.5 times the pore volume of the hierarchical nanoporous aluminophosphate with the hydrous aluminophosphate, ≪ / RTI >

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