JP5083882B2 - Cleavage layered crystal of triethylamine aluminophosphate compound and process for producing the same - Google Patents

Description

  The present invention relates to a novel cleaving layered crystal of a triethylamine aluminophosphate compound and a method for producing the same.

Conventionally, aluminophosphate compounds having various crystal structures are known, and the crystal structure is generally characterized by a powder X-ray diffraction pattern. (For example, see Patent Documents 1 and 2)
Japanese Patent Publication No. 5-74523 JP 2003-146650 A

For example, in the crystalline aluminophosphate described in Patent Document 2, a basic unit composed of an oxygen tetrahedron having aluminum or phosphorus as a center is connected three-dimensionally by sharing apex oxygen with other tetrahedral basic units. However, it is of the zeolite type in which hexagonal crystals having oxygen 18-membered ring pores are formed. This structure is defined as VFI as an IZA structure code. The IZA structure code was established in this field by the International Zeolite Association Structure Commission, which gave a three-letter code to various framework topologies represented by zeolites for which sufficient structural analysis data was available. Definition. (For example, see Non-Patent Document 1)
Since these crystalline aluminophosphates are useful as molecular sieves, catalysts, and the like, various attempts have been made to synthesize compounds having novel crystal structures by paying attention to nano-level crystal structures.
J. et al. Vac. Soc. Jpn. (Vacuum) Vol. 49, no. 4,2006,205-212

  The present invention has been made in view of such circumstances, and provides a cleavage layered crystal of an aluminophosphate compound having a novel crystal structure not found in conventional aluminophosphates, and a method for producing the same. For the purpose.

  As a result of intensive studies, the present inventors have selected triethylamine as an amino compound to be used when obtaining an aluminophosphate crystal, and by heating for a longer time after a crystal having a known structure is obtained, Completed the present invention by finding that a novel cleaving layered crystal having an absorption peak in FT-IR (light absorption in the infrared region) and a peak in a powder X-ray diffraction pattern not found in a salt crystal can be obtained. It is a thing.

That is, in the present invention, the following configurations 1 to 9 are adopted.
1. A cleavage layered crystal of an aluminophosphate triethylamine compound having a hydroxyl group bonded to an Al or P atom represented by the following general formula (1):
_{AlP x O y (OH) z} · [(C 2 H 5) 3 N] u · (H 2 O) v (1)
Where x = 1 ± 0.1
y = 4-5
z = 0.5-2
u = 0.1-0.3
v = 0-0.01
It is.
2. 2. The layered crystal according to 1, wherein the layered crystal has an absorption peak at 3755 ± 2 cm ⁻¹ by FT-IR.
3. In the layered crystal, the unit cell is a hexagonal lattice of a = b = 9.415 ± 0.010Å, c = 52.29 ± 0.05Å, α = β = 90 °, γ = 120 °, or 1 or 2 The layered crystal described in 1.
4). 4. The layered crystal according to any one of 1 to 3, wherein the layered crystal has the following peak in a powder X-ray diffraction pattern.
Surface spacing d (Å)
26.4 ± 0.2
13.10 ± 0.04
8.17 ± 0.01
8.07 ± 0.01
4.739 ± 0.005
4.079 ± 0.004
3.501 ± 0.003
3.002 ± 0.002
Typical powder X-ray diffraction patterns of the layered crystal of the present invention include those having peaks described in Table 1 of Example 1 described later. Among these peaks, the above-mentioned peaks are preferably used to identify layered crystals.
5. The layered crystal according to any one of 1 to 4, wherein the layer thickness of each layer constituting the layered crystal is 30 to 200 nm.
6). Al source, P source, water and triethylamine are mixed to prepare a mixture having the following composition based on the molar ratio of the oxide,
_{P 2 O 5 / Al 2 O} 3 = 0.5~1.5
_{H 2 O / Al 2 O 3} = 100~400
_{N (C 2 H 5) 3} / Al 2 O 3 = 1~5
6. The method for producing a layered crystal according to any one of 1 to 5, wherein the mixture is heated to 150 to 230 ° C. to obtain a layered crystal.
7). 7. The method for producing a layered crystal according to 6, wherein the mixture is heated until the obtained layered crystal shows an absorption peak at 3755 ± 2 cm ⁻¹ by FT-IR.
8). The method for producing a layered crystal according to 6 or 7, wherein the mixture is heated until the obtained layered crystal has the following peak in the powder X-ray diffraction pattern.
Surface spacing d (Å)
26.4 ± 0.2
13.10 ± 0.04
8.17 ± 0.01
8.07 ± 0.01
4.739 ± 0.005
4.079 ± 0.004
3.501 ± 0.003
3.002 ± 0.002
9. The method for producing a layered crystal according to any one of 6 to 8, wherein the mixture is heated at a pH of 3 to 8.

  According to the present invention, a layered crystal having a cleavage property, which is completely different from a conventional aluminophosphate crystal, can be obtained. Since this cleaved layered crystal is a very thin insulator substance, it can be widely used in a field related to electronic devices as a material for forming a film on the surfaces of various substrates and electrodes by coating or the like. Moreover, it is useful as a starting material for application to gas adsorption / catalyst and synthesis of a novel inorganic porous material.

In the present invention, an Al source, a P source, water and triethylamine are mixed to prepare a mixture having the following composition based on the molar ratio of the oxide,
_{P 2 O 5 / Al 2 O} 3 = 0.5~1.5
_{H 2 O / Al 2 O 3} = 100~400
_{N (C 2 H 5) 3} / Al 2 O 3 = 1~5
By heating the mixture to 150 to 230 ° C., layered crystals are obtained.

When the mixture is heated, an aluminophosphate crystal having a known structure is first obtained. However, the crystal structure is changed by further heating for a long time, and is completely different from the conventional aminophosphate crystal. A cleaved layered crystal having an absorption peak at 2 cm ⁻¹ is obtained. This absorption peak is considered to be due to a hydroxyl group bonded to Al or P atom, but a cleavage-type layered crystal exhibiting such an absorption peak has never been known so far, and was obtained for the first time by the present invention. It is.

  Further, the cleavage layered crystal of the present invention has a unit cell of a layered crystal in a hexagonal lattice of a = b = 9.415 ± 0.010 Å, c = 52.29 ± 0.05 Å, α = β = 90 °, γ = 120 °. It is also characterized by being.

Furthermore, the cleavage layered crystal of the present invention is also characterized by having the following peak in the powder X-ray diffraction pattern.
Surface spacing d (Å)
26.4 ± 0.2
13.10 ± 0.04
8.17 ± 0.01
8.07 ± 0.01
4.739 ± 0.005
4.079 ± 0.004
3.501 ± 0.003
3.002 ± 0.002

  The cleavage layered crystal of the triethylamine aluminophosphate compound of the present invention has an outer shape in which many thin layers having a cleavage property of about 30 to 200 nm are laminated as shown in the SEM image of FIG.

Next, a method for producing a cleavage layered crystal of a triethylamine aluminophosphate compound according to the present invention will be described.
There is no restriction | limiting in particular in Al source used for a raw material, and P source. As the Al source, aluminum hydrate, hydroxide, metal, alkoxide, oxide, or the like can be used. As the P source, phosphoric acid, phosphorus oxide, phosphate ester, or the like can be used. A material that easily reacts when both the Al source and the P source are mixed is preferably used. As the Al source, alumina sol, boehmite, pseudoboehmite, aluminum isopropoxide, and the like are preferable. As the P source, orthophosphoric acid, Polyphosphoric acid and the like are preferable.

At that time, even if the P ₂ O ₅ / Al ₂ O ₃ ratio is larger than 1.5 or smaller than 0.5, a target aluminophosphate cannot be obtained, or a phosphate crystal phase other than the target is obtained. This causes a problem that the amount of the increase increases. In addition, for example, there are problems that impurities derived from alumina increase and the recovery rate of solid components decreases. On the other hand, when the H ₂ O / Al ₂ O ₃ ratio is less than 100, the viscosity is high and the handling is hindered. If the N (C ₂ H ₅ ) ₃ / Al ₂ O ₃ ratio is greater than 5 or less than 1, the intended aluminophosphate cannot be obtained, or the amount of phosphate crystal phase other than the intended amount Will increase.

The procedure for synthesizing the cleaved layered crystal of the triethylamine aluminophosphate compound of the present invention from these raw materials is not particularly limited, but examples of the basic synthesis procedure include the following procedure.
(1) Preparation of Aqueous Solution A Disperse the Al source reagent in water (divide the amount of water so that the molar ratio is 2: 1 with aqueous solution B described below) and stir.
(2) Preparation of aqueous solution B The P source reagent is dissolved in water and stirred. Next, triethylamine is added dropwise and mixed under stirring and ice cooling.
(3) The aqueous solution B is slowly dropped into the aqueous solution A while stirring to obtain the aqueous solution C.
(4) The pH of the aqueous solution C is adjusted using a 50% by weight sulfuric acid aqueous solution.
(5) The aqueous solution C is sealed in an autoclave with a fluororesin inner cylinder.
(6) Put the autoclave in an electric furnace and heat and hold it.
(7) After completion of heating, the autoclave is removed from the electric furnace and cooled with cold water.
(8) After cooling, the autoclave is opened, and the synthesized material is filtered out and washed with ion-exchanged water.
(9) Finally, for example, it is dried at 40 ° C. for 12 hours or more.

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the following specific examples do not limit the present invention.
In the following examples, the structure and properties of the cleaved layered crystal of the obtained triethylamine aluminophosphate compound were measured as follows.
(FT-IR)
Using the Nicolet Co., Ltd. "Magna750", to measure the range of 400-4000cm ^-1 in the measurement resolution 4cm ^-1.
(X-ray diffraction data)
For precision measurement, use a BrukerAXS powder X-ray diffraction measurement device “D8 ADVANCE with Vario 1” to measure CuKα ₁ line as a source, and use the Bragg equation from the 2θ value of the diffraction line. The interval d is calculated. The dried sample is used for measurement as it is, and the range of 2θ is measured at about 2 to 50 °.
On the other hand, for the qualitative analysis, a powder X-ray diffraction measurement device “MXP-3TZ” manufactured by Mac Science Co., Ltd. is used, and a range of about 2 to 25 ° is measured using CuKα _1,2 rays as a radiation source.
(SEM observation)
Secondary electrons were observed at an acceleration voltage of 1 kV or 15 kV using Hitachi's “S-4800”. In order to perform composition analysis, an energy dispersive X-ray analyzer “EMAX Energy” manufactured by HORIBA, Ltd. attached to the SEM apparatus was used.
(NMR)
NMR spectrum of ²⁷ Al and ³¹ P nuclei using Bruker Bio-Spin's “AVANCE 400WB” using Magic angle spinning method with single pulse sequence, sample rotation speed of 5 kHz, and 100 times of integration. Was measured. Calibration was performed using Al (H ₂ O) ₆ Cl ₃ and H ₃ PO ₄ aqueous solutions as the reference for the chemical shift amount of ²⁷ Al nuclei and ³¹ P nuclei, respectively.
(TG-DTA)
By using a thermogravimetric / thermal differential (TG-DTA) analyzer “TG-DTA 2000SR” manufactured by BrukerAXS, the temperature is raised from room temperature to 1000 ° C at a rate of 10 ° C / min with dry air of 100 ml / min. The amount of water in the sample and the amount of organic matter were evaluated.
(CHN analysis)
By using “EA1110” manufactured by CE Instruments, the weight ratio of C, H, N elements derived from organic substances contained in the sample was evaluated.

Example 1
As an Al source, 80 g of an alumina sol aqueous solution (manufactured by Kawaken Fine Chemical Co., Ltd., 10 wt%) is dispersed in 183 g of water. This is referred to herein as Solution A. On the other hand, 18.6 g of orthophosphoric acid aqueous solution (85 wt%, manufactured by Wako Pure Chemical Industries, Ltd.) as a P source was dispersed in 91.3 g of water, and triethylamine [(C ₂ H ₅ ) ₃ N] (manufactured by Tokyo Chemical Industry, 99 w% +) 28.9 g Is added under ice cooling and stirring. This is referred to herein as Solution B. The solution B was added to the solution A under stirring and further sufficiently stirred to prepare a mixed aqueous solution C having the following molar composition.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 3.6
Further, to this mixed aqueous solution C, a sulfuric acid aqueous solution (manufactured by Wako Pure Chemicals, 99 wt% +) diluted to about 50 wt% was added dropwise with stirring to adjust the pH to 7.
The mixed aqueous solution was sealed in an autoclave with a Teflon (registered trademark) inner cylinder and heated at 170 ° C. for 7 days. After the heating is completed, the autoclave is cooled with cold water, an aqueous solution containing the reaction product (target sample) is taken out, and addition of pure water and decantation are repeated several times. Following this washing operation, the sample was separated and recovered by performing filtration and drying at 40 ° C. for one day.

(X-ray diffraction data)
The powder X-ray diffraction pattern of the dried sample was measured under the following conditions.
Equipment: BrukerAXS D8 ADVANCE with Vario-1
Measurement method: Transmission type Debye-Scherrer optical system using a sample sealed in a glass capillary Measurement interval: Δ2θ = 0.00874 °
Measuring range: 2θ = 1.8−90 °
The results are shown in FIG. The inset in the figure is an enlargement of the vertical axis strength of 2θ = 10 to 35 °. The symbol “|” in the figure indicates the lattice constant a = b = 9.4154 (3) Å, c = 52.293 (2) Å, α = β = 90 Denotes the position of the diffraction peak that appears at °, γ = 120 °, and matches the actual diffraction peak position. By using Bragg's diffraction condition formula (2dsinθ = λ _CuKα1 ), the lattice spacing of the diffraction peak and its relative intensity are as shown in Table 1, and these compounds containing known aluminophosphate compounds and amine organic compounds. None of these exhibit diffraction peaks.

In Table 1, the abbreviations in the right column represent the following meanings.
vs: quite strong s: strong m: intermediate w: weak vs: weak

(SEM observation)
Scanning electron microscope (SEM) image observation of the sample obtained in Example 1 was performed. The measurement conditions are as follows.
Equipment: Hitachi S-4800
Composition analysis accessory: EMAX Energy manufactured by HORIBA, Ltd.
SEM observation images are shown in FIGS. As seen in FIG. 2 (a), it has an outer shape in which hexagonal plate-like substances are ordered and stacked. When this image is enlarged, as shown in FIG. 2 (b), a portion where the plate-like structures are joined together without shifting is observed. From this, this substance was obtained by forming a plate so that the hexagonal column crystal was cleaved. The thickness of the cleaved portion of the plate-like substance is about 200 nm. As the cleavage progresses, a hexagonal sheet-like structure that is completely peeled as shown in FIG. 2C or a form in which the sheets are gathered as shown in FIG.
Furthermore, the ratio of Al and P atoms contained in the sample was analyzed by an energy dispersive X-ray fluorescence analyzer attached to the SEM apparatus. As a result, a result of Al: P = 1: 1 ± 0.1 was obtained.

(FT-IR)
The powder diffuse reflectance spectrum in the mid-infrared region of the sample obtained in Example 1 was measured under the following conditions.
Device: Nicolet Magna750
Measurement resolution: 4 cm ^-1
Integration count: 512 times Measurement range: 400-4000cm ^-1
The results are shown in FIG. Since the vertical axis represents the diffuse reflectance, the lower the diffuse reflectance, the stronger the light absorption. The light absorption observed at 3755 ± 2 cm ⁻¹ is due to stretching vibration of —OH group (hydroxyl group). This —OH group is considered to be chemically bonded to the Al or P atom. Such —OH group-containing aluminophosphate compounds having a stretching vibration of 3755 ± 2 cm ⁻¹ and these compounds encapsulating amine organic substances have not been known in the past.

(TG-DTA)
The thermogravimetric / thermal differential analysis of the sample obtained in Example 1 was performed under the following conditions.
Equipment: TG-DTA-2000SR manufactured by BrukerAXS
Gas used and flow rate: Dry air, 100 ml / min Temperature rising speed: 10 ° C / min The results are shown in FIG. The solid line represents the weight reduction ratio as the temperature rises, and the broken line represents the thermal characteristics (positive direction: heat generation, negative direction: endothermic characteristics). Although there was a gradual increase in calorific value and a decrease in weight with a rise in temperature from room temperature, a sudden decrease in weight occurred at around the exothermic peak of 330 ° C. This means that there is no endothermic reaction due to desorption of adsorbed water generally found in porous crystals, and only heat generation due to combustion of triethylamine occurs. Therefore, this sample had almost no adsorbed water, and the main component of weight reduction was triethylamine.
Further, the amount of CHN element contained in the sample was quantified by organic element quantitative analysis. EA1110 manufactured by CE Instruments was used as a measuring device. As a result, the amount of triethylamine contained in the sample was TEA / Al = 0.2 in terms of atomic ratio to Al.

(NMR)
The MAS (Magic Angle Spinning) -NMR (nuclear magnetic resonance) spectrum for the ²⁷ Al and ³¹ P nuclear spins of the sample obtained in Example 1 was measured under the following conditions.
Equipment: Bruker AVANCE 400WB
MAS frequency: 5 kHz
Accumulation count: 100 times Standard sample: ²⁷ Al nucleus: Al (H ₂ O) ₆ Cl ₃ , ³¹ P nucleus: H ₃ PO ₄ aqueous solution MAS-NMR spectra of the ²⁷ Al and ³¹ P obtained are shown in FIG. ) And FIG. 5 (b).
Many peaks are observed in the NMR spectrum of ²⁷ Al between -10 and 60 ppm. In addition, the peak marked with * is a side band accompanying MAS.

(Example 2: Synthesis time)
Regarding the method for producing this sample, an example relating to the heating time of the mixed solution containing the Al source, the P source and triethylamine prepared according to Example 1 and the amount of the obtained sample will be shown.
A mixed solution is prepared and heated by the same procedure as in Example 1 to obtain a target sample. However, 90 g of an alumina sol aqueous solution (manufactured by Kawaken Fine Chemical Co., Ltd., 10 wt%) is dispersed in 205 g of water. On the other hand, 30.0 g of an orthophosphoric acid aqueous solution (manufactured by Wako Pure Chemicals, 85 wt%) and 27.1 g of triethylamine (manufactured by Tokyo Chemical Industry, 99 w% +) are dispersed in 103 g of water. The molar ratio of the resulting mixed aqueous solution is as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 3.0
Furthermore, after adjusting the pH of this mixed aqueous solution to 3.6 with a sulfuric acid aqueous solution (99 wt% +, manufactured by Wako Pure Chemical Industries) diluted to about 50 wt%, it is heated at 190 ° C for 1,2,3,6,10 days. A sample was collected in the same manner as in Example 1.
The powder X-ray diffraction pattern of the sample was measured under the following conditions.
Equipment: MXP-3TZ manufactured by Mac Science
Measurement method: Concentrated optical system using a flat specimen (DS, SS: variable slit mode [constant specimen irradiation area], RS = 0.15 mm)
X-ray wavelength used: CuKα _1,2
Measurement interval: Δ2θ = 0.012 °
Measuring range: 2θ = 1.4−16 °
The results are shown in FIG. Only X-ray diffraction peaks due to known AFI-type aluminophosphate crystals (reference: T. Kodaira et al., Microporous and Mesoporous Materials, 29 (1999) 329-337.) Appear on heating for 1-2 days. By heating for 3 days or longer, the same position as the powder XRD peak of the target substance shown in Example 1 and a peak of relative intensity (indicated by ▼ in the figure) can be obtained. After heating for 10 days, the XRD peak derived from the AFI type aluminophosphate crystal phase disappears completely. Therefore, the heating time is 3 days or more, preferably 10 days or more.

(Example 3: Heating temperature dependence)
Regarding the method for producing this sample, an example relating to the correlation between the heating temperature of the mixed solution containing the Al source, the P source and triethylamine prepared in Example 1 and the obtained sample will be shown.
A mixed solution is prepared and heated by the same procedure as in Example 1 to obtain a target sample. The procedure for obtaining the mixed solution and the raw material weight are the same as in Example 1. Therefore, the molar ratio of the obtained mixed aqueous solution is as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 3.6
Further, the mixed aqueous solution was adjusted to 7.0 by the same method as in Example 1, heated at 190, 210 ° C. for 3 days, and the sample was recovered in the same manner as in Example 1. The powder X-ray diffraction pattern of the sample was measured under the same conditions as in Example 2.
The results are shown in FIG. X-ray diffraction peaks characterizing the aluminophosphate crystals shown in Example 1 are observed at both heating temperatures of 190 and 210 ° C. The “*” mark indicates a peak derived from the AFI type aluminophosphate crystal. In conclusion, synthesis is possible in the range of 150 to 230 ° C, but 170 to 190 ° C is optimal when the other synthesis parameters except temperature are the same.

(Example 4: pH dependence)
Regarding the production method of this sample, an example relating to the correlation between the pH of the mixed solution containing Al source, P source and triethylamine prepared in Example 1 and the obtained sample will be shown.
A mixed solution is prepared and heated by the same procedure as in Example 1 to obtain a target sample. The procedure for obtaining the mixed solution and the raw material weight are the same as in Example 1. Therefore, the molar ratio of the obtained mixed aqueous solution is as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 3.6
Further, the pH of the mixed aqueous solution was adjusted to 4.0, 5.0, 6.0, 7.0 in the same manner as in Example 1, heated at 170 ° C. for 7 days, and the sample was recovered in the same manner as in Example 1. . The powder X-ray diffraction pattern of the sample was measured under the same conditions as in Example 2.
The result is shown in FIG. The diffraction peak indicated by “▼” is derived from the target aluminophosphate crystal. At pH = 4.0 to 5.0, an AFI crystal phase indicated by “*” is slightly observed, but at pH = 7.0, there is no XRD peak completely derived from the AFI crystal phase. Therefore, the target sample is obtained in the range of 4 to 8 as the pH of the mixed solution. For the purpose of increasing the purity of the sample, increasing the yield, and shortening the heating time, the pH is desirably 6.0 to 7.0.

(Example 5: Amine amount dependency)
Regarding the production method of this sample, an example relating to the correlation between the amount of triethylamine in the mixed solution containing the Al source, the P source and triethylamine prepared according to Example 1 and the obtained sample will be shown.
A mixed solution was prepared by the same procedure as in Example 1, but the molar ratio of the raw materials was prepared as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 2.0, 2.5, 3.0
Further, the pH of the mixed aqueous solution was adjusted to 4.0 by the same method as in Example 1, heated at 190 ° C. for 7 days, and the sample was collected by the same method as in Example 1 after the heating was completed. The powder X-ray diffraction pattern of the sample was measured under the same conditions as in Example 2.
The result is shown in FIG. Aluminophosphate crystals having the desired crystal structure were obtained with any amount of triethylamine. Therefore, synthesis is possible in the range of TEA / Al ₂ O ₃ = 1-4, including the TEA / Al ₂ O ₃ = 3.6 ratio in Example 1.

(Example 6: amount of water)
Regarding the method for producing this sample, an example relating to the correlation between the total amount of water in the mixed solution containing the Al source, P source and triethylamine prepared in Example 1 and the obtained sample will be shown.
A mixed solution was prepared by the same procedure as in Example 1, but the molar ratio of the raw materials was prepared as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 200
TEA / Al ₂ O ₃ = 3.6
Further, the pH of the mixed aqueous solution was adjusted to 4.0 by the same method as in Example 1 and heated at 170 ° C. for 10 days. After the heating was completed, the sample was recovered by the same method as in Example 1. The powder X-ray diffraction pattern of the sample was measured under the same conditions as in Example 2.
The result is shown in FIG. Compared to the case of Example 1, an aluminophosphate crystal having the target crystal structure was obtained even if the amount of water was reduced. However, some aluminophosphate crystals having an AFI structure marked with “*” are also mixed. Thus, including _{H 2 O / Al 2 O 3} = 250 ratio in Example 1, it is possible to synthesize a range of _{H 2 O / Al 2 O 3} = 50-500. However, as the amount of water increases, the amount of the target substance obtained from the unit volume of the starting aqueous mixture decreases, whereas when the amount of water decreases, the temperature and pH range at which the target aluminophosphate crystals can be obtained narrows. Further, since the heating time is extended, it is desirable to prepare a mixed solution with H ₂ O / Al ₂ O ₃ = 200 to 300.

(Example 7: Type of Al source)
In addition to the alumina sol shown in Example 1, pseudo-boehmite [Product name: Catapal B, manufactured by Sasol North America], aluminum triisopropoxide (Al (OCH (CH ₃ ) ₂ ) ₃ Examples of synthesis using [Aldrich] and aluminum hydroxide (Al (OH) ₃ ) [Merck] are shown.
A mixed solution is prepared and heated by the same procedure as in Example 1 to obtain a target sample. The molar ratio of the resulting mixed aqueous solution was unified as follows.
P ₂ O ₅ / Al ₂ O ₃ = 1.0
H ₂ O / Al ₂ O ₃ = 250
TEA / Al ₂ O ₃ = 3.6
When aluminum isopoloxide is used, isopropyl alcohol is contained in the solution A by hydrolysis.
Further, after adjusting the pH of this mixed aqueous solution to 5.0 by the same method as in Example 1, heating was performed at 190 ° C. for 21 days, and the sample was recovered by the same method as in Example 1. The powder X-ray diffraction pattern of the sample was measured under the same conditions as in Example 2.
The results are shown in FIG. A sample having the same powder XRD pattern as Example 1 was obtained except that Al (OH) ₃ was used as the Al source. Al (OH) ₃ hardly dissolved in water, and the target sample could not be obtained. Therefore, the Al source is not particularly limited as long as it is a reagent that dissolves and decomposes uniformly in water.

FIG. 3 is a diagram showing a powder X-ray diffraction pattern of the crystal obtained in Example 1. 2 is an SEM observation image of the crystal obtained in Example 1. 2 is an SEM observation image of the crystal obtained in Example 1. 2 is an SEM observation image of the crystal obtained in Example 1. 2 is an SEM observation image of the crystal obtained in Example 1. 2 is a powder diffuse reflectance spectrum in the mid-infrared region of the crystal obtained in Example 1. FIG. FIG. 3 is a diagram showing the results of thermogravimetric / thermal differential analysis of the crystals obtained in Example 1. 2 is a diagram showing a ²⁷ Al MAS-NMR spectrum of the crystal obtained in Example 1. FIG. 2 is a diagram showing a ³¹ P MAS-NMR spectrum of the crystal obtained in Example 1. FIG. 3 is a diagram showing a powder X-ray diffraction pattern of crystals obtained in Example 2. FIG. FIG. 4 is a graph showing a powder X-ray diffraction pattern of the crystal obtained in Example 3. 6 is a diagram showing a powder X-ray diffraction pattern of crystals obtained in Example 4. FIG. 6 is a graph showing a powder X-ray diffraction pattern of the crystal obtained in Example 5. FIG. 6 is a graph showing a powder X-ray diffraction pattern of the crystals obtained in Example 6. FIG. 6 is a graph showing a powder X-ray diffraction pattern of crystals obtained in Example 7. FIG.

Claims (9)

A cleavage layered crystal of an aluminophosphate triethylamine compound having a hydroxyl group bonded to an Al or P atom represented by the following general formula (1):
_{AlP x O y (OH) z} · [(C 2 H 5) 3 N] u · (H 2 O) v (1)
Where x = 1 ± 0.1
y = 4-5
z = 0.5-2
u = 0.1-0.3
v = 0-0.01
It is. The layered crystal according to claim 1, wherein the layered crystal has an absorption peak at 3755 ± 2 cm ⁻¹ by FT-IR.   2. The layered crystal according to claim 1, wherein the unit cell forms a hexagonal lattice of a = b = 9.415 ± 0.01010, c = 52.29 ± 0.05Å, α = β = 90 °, γ = 120 °. Or the layered crystal of 2. The layered crystal according to any one of claims 1 to 3, wherein the layered crystal has the following peak in a powder X-ray diffraction pattern.
Surface spacing d (Å)
26.4 ± 0.2
13.10 ± 0.04
8.17 ± 0.01
8.07 ± 0.01
4.739 ± 0.005
4.079 ± 0.004
3.501 ± 0.003
3.002 ± 0.002   The layered crystal according to any one of claims 1 to 4, wherein the layer thickness of each layer constituting the layered crystal is 30 to 200 nm. Al source, P source, water and triethylamine are mixed to prepare a mixture having the following composition based on the molar ratio of the oxide,
_{P 2 O 5 / Al 2 O} 3 = 0.5~1.5
_{H 2 O / Al 2 O 3} = 100~400
_{N (C 2 H 5) 3} / Al 2 O 3 = 1~5
The method for producing a layered crystal according to any one of claims 1 to 5, wherein the mixture is heated to 150 to 230 ° C to obtain a layered crystal. The method for producing a layered crystal according to claim 6, wherein the mixture is heated until the obtained layered crystal shows an absorption peak at 3755 ± 2 cm ⁻¹ by FT-IR. The method for producing a layered crystal according to claim 6 or 7, wherein the mixture is heated until the obtained layered crystal has the following peak in the powder X-ray diffraction pattern.
Surface spacing d (Å)
26.4 ± 0.2
13.10 ± 0.04
8.17 ± 0.01
8.07 ± 0.01
4.739 ± 0.005
4.079 ± 0.004
3.501 ± 0.003
3.002 ± 0.002   The method for producing a layered crystal according to any one of claims 6 to 8, wherein the mixture is heated to a pH of 3 to 8.