WO2018061827A1 - Zeolite and method for producing same - Google Patents

Abstract

Zeolite according to the present invention has an X-ray diffraction pattern that contains at least lattice spacings d (Å) shown in Table 1 as measured by a powder X-ray diffraction method.

Description

Zeolite and its production method

The present invention relates to a zeolite having a novel framework and a method for producing the same.
This application claims priority on the basis of Japanese Patent Application No. 2016-191110 filed in Japan on September 29, 2016, the contents of which are incorporated herein by reference.

As a material having a catalytic function, zeolites having various structures have been discovered and attracted attention. Variations in the zeolite framework structure have increased from about 100 to about 230 in the last 20 years. Use of an organic template molecule, that is, a structure directing agent (SDA) is effective in creating various zeolite structures.

In particular, in order to synthesize a large-pore zeolite having a ring structure of oxygen and a tetrahedral atom (= T atom; silicon, etc.) and having 12-membered or larger pores counted by oxygen, a complex and bulky organic molecule is used. The idea of using it as a regulating agent has become mainstream (Non-Patent Document 1). However, when bulky organic polymers are used, zeolites with high silica composition with low aluminum content tend to be synthesized, and as they are, there are few ion exchange sites. It is said that it is not suitable for. In addition, when producing a large pore zeolite according to the conventional concept, precise design and synthesis are required, and the success rate is low.

In order to synthesize a new framework zeolite with a high aluminum content, it is considered necessary to use a structure-directing agent having a simpler structure. For example, quaternary ammonium compounds such as tetraalkylammonium, when properly designed, act as templates in the hydrothermal synthesis of zeolites and induce crystallization of various framework structures. In addition, dimethyldipropylammonium compounds have a simple structure and are known to serve as templates for MSE, which is a useful skeleton.

However, in the conventional method in which hydrothermal synthesis is performed using a silica source, an alumina source, an alkali source, and the above-mentioned structure-directing agent as raw materials, and using about 40 times more water than the silica source, a large amount of aluminum is used. Including (for example, Si / Al = 7 to 10), a new framework zeolite cannot be obtained.

The present invention has been made in view of such circumstances, and an object thereof is to provide a zeolite having a novel skeleton having a high aluminum content. Another object of the present invention is to provide a method for producing zeolite, which makes it possible to produce the zeolite more reliably by using a structure directing agent having a simple structure.

The present inventor has conducted intensive studies and reduced the ratio of water used as a raw material to a lower level than before and can obtain a zeolite having a new framework by, for example, about 6 to 8 times the silica source used for the raw material. I found. The present invention provides the following features or means.
[1] The zeolite according to one aspect of the present invention has an X-ray diffraction pattern including at least a lattice spacing d (Å) and a relative intensity shown in Table 1 below as measured by a powder X-ray diffraction method. The intensity indicates the ratio of the intensity of the other peak to the intensity of the maximum peak among the peaks included in the X-ray diffraction pattern.
[2] In the zeolite according to [1], the pore volume estimated by nitrogen adsorption measurement is preferably 0.12 ml / g or more and 0.25 ml / g or less.
[3] In the zeolite according to any one of [1] and [2], the zeolite has a plurality of oxygen 8-membered rings and oxygen 12-membered rings independent of each other, and the plurality of oxygen 8-membered rings are in a plurality of groups. In each group, the oxygen 8-membered rings are overlapped so as to have a common through-hole in one direction, and the plurality of oxygen 12-membered rings are divided into a plurality of groups, The oxygen 12-membered ring overlaps with a common through hole in a direction parallel to one plane, and the oxygen 8-membered ring overlapping direction and the oxygen 12-membered ring overlapping direction intersect each other. It is preferable.
[4] In the zeolite according to [3], the oxygen 8-membered ring is connected so that a pair and an isolated one form a line in an alternating direction in a direction intersecting the overlapping direction. Preferably, the rows are connected so that the oxygen 8-membered ring and the isolated oxygen 8-membered ring are adjacent to each other.
[5] In the zeolite according to any one of [3] and [4], the oxygen 12-membered ring may be connected side by side at equal intervals in two directions in a plane intersecting the overlapping direction. preferable.
[6] In the zeolite according to any one of [3] to [5], the pore diameter of the oxygen 8-membered ring is 0 when the length of two oxygen ionic radii (0.135 nm) is subtracted. 295 nm or more and 0.454 nm or less, 0.565 nm or more and 0.724 nm or less when not subtracted, and the pore diameter of the oxygen 12-membered ring is 0.595 nm when the length of two oxygen radii (0.135 nm) is subtracted If it is not subtracted, it is preferably 0.865 nm or more and 0.980 nm or less.
[7] In the zeolite according to any one of [1] to [6], the number density of T atoms contained is preferably 15 atoms / nm ³ or more and 18 atoms / nm ³ or less.
[8] A method for producing a zeolite according to one aspect of the present invention is the method for producing a zeolite according to any one of [1] to [7], wherein the first silica source, the alkali source, water, And a first preparation step for preparing the mixture of structure directing agents with stirring, a first heating step for heating the prepared mixture with stirring, a cooling step for cooling the heated mixture, and cooling A second preparation step in which a second silica source and an alumina source are added to the mixture and re-adjusted while stirring, a second heating step in which the re-prepared mixture is heated, and the heated mixture is washed and The first preparation step includes, in order, a drying step of filtering and drying, and a third heating step of heating the organic composite obtained through the drying step and removing the organic matter contained therein. Amount of water used in The amount of the first silica source and the amount of the second silica source are 6 to 8 times the total, and colloidal silica is used as the first silica source, and the second silica source and alumina Y-type zeolite is used as the source, and dimethyldipropylammonium compound is used as the structure-directing agent.

The zeolite of the present invention is a crystalline aluminosilicate porous body having a novel skeleton, and has a high aluminum content and a large number of ion exchange sites. ing. Moreover, since the zeolite of this invention can introduce | transduce a hetero element through dealumination, it may be utilized as a catalyst for various basic chemicals manufacture.

Furthermore, the zeolite of the present invention can be applied as a solid catalyst that promotes catalytic decomposition of paraffin. In the zeolite of the present invention, a part of aluminum constituting the zeolite can be replaced with the same type by a transition metal (titanium, tin, etc.). For example, zeolite with the same type substitution with titanium is an excellent catalyst for selective oxidation of olefins, paraffins and aromatic rings using oxygen, hydrogen peroxide, alkyl hydroperoxide or the like as an oxidizing agent.

According to the method for producing a zeolite of the present invention, a zeolite having a high aluminum content and a novel skeleton can be obtained. In the method for producing a zeolite of the present invention, as an example, a dimethyldipropylammonium compound is used as a structure-directing agent having a simple structure, and the amount of water used as a raw material is the same as the amount of silica source used in the raw material. About 6 to 8 times. As a result, the zeolite can be easily and reliably produced with high purity as compared with the case of using a conventional production method in which the amount of water is about 40 times the amount of silica. It becomes easy to realize production. Further, since the synthesis of the structure directing agent is simplified, the energy required for the synthesis process can be reduced, and the manufacturing cost can be greatly reduced.

It is the figure which planarly viewed the structure of the zeolite which concerns on one Embodiment of this invention from one direction. It is the figure which planarly viewed the structure of the zeolite which concerns on one Embodiment of this invention from another one direction. It is a graph which shows the result of having analyzed by X-ray diffraction about the zeolite concerning one embodiment of the present invention. It is a graph which shows the result of having performed nitrogen adsorption measurement about the zeolite concerning one example of the present invention. It is a graph which shows the result of having performed the ²⁷ Al MAS NMR measurement about the zeolite which concerns on one Example of this invention. It is a graph which shows the result of having performed ²⁹ Si MAS NMR measurement about the zeolite which concerns on one Example of this invention. It is a SEM photograph of the zeolite concerning one example of the present invention. It is a SEM photograph of the zeolite concerning other examples of the present invention.

Hereinafter, a zeolite that is an embodiment to which the present invention is applied and a manufacturing method thereof will be described in detail with reference to the drawings. In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. In addition, the materials, dimensions, and the like exemplified in the following description are examples, and the present invention is not limited to them, and can be appropriately changed and implemented without changing the gist thereof.

[Configuration of zeolite]
A configuration of the zeolite 100 according to an embodiment of the present invention will be described with reference to FIGS. 1A and 1B. Here, the three-dimensional space is represented by the x-axis, y-axis, and z-axis orthogonal to each other, and directions substantially parallel to the x-axis, y-axis, and z-axis are the x-axis direction, y-axis direction, and z-axis direction, respectively Shall be called. FIG. 1A is a plan view of the structure of zeolite 100 from one direction (z-axis direction). FIG. 1B is a plan view of the structure of zeolite 100 from another direction (x-axis direction).

The zeolite (crystalline aluminosilicate porous body) 100 has a plurality of oxygen 8-membered rings 101 (101a, 101b) and a plurality of oxygen 12-membered rings 102, which are independent of each other. As will be described later, the oxygen 8-membered ring 101a is isolated in the y-axis direction, that is, separated from other oxygen 8-membered rings 101a in the y-axis direction. Further, the oxygen 8-membered ring 101b is in contact with another oxygen 8-membered ring 101b in the y-axis direction to form a pair.

The pore diameter of the oxygen 8-membered ring 101 is 0.295 nm or more and 0.454 nm or less when the ionic radius of oxygen (0.135 nm) is taken into consideration, that is, when the length of two ionic radii of oxygen is subtracted. Preferably there is. The pore diameter of the oxygen 8-membered ring 101 is 0.565 nm or more and 0.000 when the ionic radius of oxygen (0.135 nm) is not considered, that is, when the length of two ionic radii of oxygen is not subtracted. It is preferable that it is 724 nm or less.

The pore diameter of the oxygen 12-membered ring 102 is 0.595 nm or more and 0.710 nm or less when the ionic radius (0.135 nm) of oxygen is taken into account, that is, when the length of two ionic radii of oxygen is subtracted. Preferably there is. The pore diameter of the oxygen 12-membered ring 102 is 0.865 nm or more and 0 when the ionic radius of oxygen (0.135 nm) is not taken into consideration, that is, when the length corresponding to two ionic radii of oxygen is not subtracted. It is preferable that it is 980 nm or less.

The pore volume of the entire zeolite 100 estimated by nitrogen adsorption measurement is usually 0.12 ml / g or more and 0.25 ml / g or less, preferably 0.15 ml / g or more and 0.20 ml / g or less, More preferably, it is 0.16 ml / g or more and 0.19 ml / g or less.

The skeleton density of the zeolite 100, that is, the number density of T atoms contained (the number of T atoms (such as silicon) per 1 nm ³ ) is usually 15 atoms / nm ³ or more and 18 atoms / nm ³ or less. preferably pieces / nm ³ or more 17 / nm ³ or less, more preferably not more than 16.6 pieces / nm ³ nm.

The plurality of oxygen 8-membered rings 101a are divided into a plurality of groups 101A, and in each group 101A, the oxygen 8-membered rings 101a overlap so as to have a common through hole in one direction (z-axis direction). The plurality of oxygen 8-membered rings 101b are divided into a plurality of groups 101B, and in each group 101B, the oxygen 8-membered rings 101b overlap so as to have a common through hole in one direction (z-axis direction). Yes. The plurality of groups 101A and 101B are arranged so that pairs of groups 101A and 101B alternate in the y-axis direction.

Each of the plurality of oxygen 8-membered rings 101a constituting each group 101A is connected to each of the plurality of oxygen 8-membered rings 101b constituting the adjacent group 101B via an oxygen 6-membered ring. Each of the plurality of oxygen 8-membered rings 101b constituting each group 101B is connected to each of the plurality of oxygen 8-membered rings 101a constituting one adjacent group 101A via an oxygen 6-membered ring. Yes. Further, each of the plurality of oxygen 8-membered rings 101b constituting each group 101B is directly connected to each of the plurality of oxygen 8-membered rings 101b constituting the other adjacent group 101B.

The overlapping direction of the oxygen 8- membered rings 101a and 101b is preferably substantially parallel to the z-axis direction. In one direction (y-axis direction) intersecting the overlapping direction (z-axis direction) of the oxygen 8-membered ring, pairs of oxygen 8-membered rings 101B and groups of isolated oxygen 8-membered rings 101A are alternately arranged. Are connected to form a column 101C. Each of the two groups 101B forming a pair is aligned along the y-axis direction. The separation distance d1 between one of the paired groups 101B and the isolated group 101A is about 0.519 to 0.530 nm.

The columns 101C are connected to each other via a plurality of oxygen 5-membered rings so that pairs of the oxygen 8-membered ring 101a and the oxygen 8-membered ring 101b are adjacent to each other. The separation distance d2 between the columns 101C is about 0.27 nm.

The plurality of oxygen 12-membered rings 102 are divided into a plurality of groups 102A, and in each group 102A, the oxygen 12-membered ring 102 is in a direction substantially parallel to the xy plane (a direction substantially parallel to one plane), preferably Are overlapped so as to have a common through hole in a direction parallel to the xy plane (a direction parallel to one plane). The plurality of groups 102A are arranged in the y-axis direction. A plurality of oxygen 12-membered rings 102 constituting each group 102A are connected to a plurality of oxygen 12-membered rings 102 constituting adjacent groups 102A via oxygen 4-membered rings and / or oxygen 5-membered rings, respectively. Yes. The overlapping direction of the oxygen 12-membered ring 102 is preferably substantially parallel to the x-axis direction.

The group of oxygen 12-membered rings 102A is arranged at equal intervals (d3, d4) in two directions (y-axis direction and z-axis direction) in a plane intersecting the overlapping direction (x-axis direction) of the oxygen 12-membered ring. It is connected. Specifically, the groups 102A are arranged at intervals of about 0.810 to 0.830 nm (d3) in the y-axis direction and at intervals of about 0.240 to 0.260 nm (d4) in the z-axis direction.

The overlapping direction of the oxygen 8-membered ring and the overlapping direction of the oxygen 12-membered ring intersect each other. In reality, they intersect at an angle of about 89 degrees or more and 91 degrees or less and tend to be substantially orthogonal (substantially orthogonal), but are preferably orthogonal.

In the structure described above, the molar ratio of silicon to aluminum (Si / Al) is 8.0 or more and 9.1 or less. This molar ratio can be confirmed by, for example, elemental analysis by inductively coupled plasma atomic emission spectrum (ICP-AES), atomic absorption analysis, fluorescent X-ray analysis, and the like.

The structure of zeolite can be uniquely identified from the analysis result by X-ray diffraction (XRD). In the examples described later, X-ray diffraction analysis results for the zeolite 100 are obtained, and those skilled in the art can determine that the zeolite 100 actually has the above-described structure based on the analysis results. it can. Note that the fact that the zeolite 100 has the above-described structure has also been verified by analysis of X-ray diffraction by a specialized institution.

That is, the zeolite 100 according to the present embodiment is a zeolite in which at least the lattice spacing d (d-spacing) (Å) shown in Table 2 is detected by powder X-ray diffraction measurement. More specifically, the zeolite 100 is a zeolite having an X-ray diffraction pattern including at least a lattice spacing d (Å) and a relative intensity shown in Table 2 as measured by a powder X-ray diffraction method. The relative intensity shows the ratio of the intensity of the other peak to 100, where the intensity of the maximum peak among the peaks included in the X-ray diffraction pattern is 100. Here, the intensity of the peak corresponding to the lattice spacing d (Å) of 3.43 ± 0.10 is maximized.

The zeolite according to this embodiment preferably has the following chemical composition represented by a molar ratio.
X ₂ O ₃ : (n) YO ₂

The above X is a trivalent element. Although it does not specifically limit as a trivalent element, Usually, boron, aluminum, iron, and gallium are preferable, and boron, aluminum, and gallium are especially preferable from points, such as the ease of producing | generating a zeolite crystal. The trivalent element X may be composed of one type of trivalent element or may be a combination of two or more types of trivalent elements. Among these, the zeolite according to the present embodiment preferably contains aluminum as the trivalent element X. In this case, the aluminum content is preferably 50 mol% or more, more preferably 80 mol% or more of the entire X.

Y is a tetravalent element. The tetravalent element is not particularly limited, but usually silicon, germanium, tin, titanium, and zirconium are preferable, and silicon, germanium, tin, and titanium are particularly preferable from the viewpoint of easy formation of zeolite crystals. . The tetravalent element Y may be composed of one type of tetravalent element or may be a combination of two or more types of tetravalent elements. Among these, the zeolite according to the present embodiment preferably contains silicon as the tetravalent element Y. In this case, the silicon content is preferably 50 mol% or more, more preferably 80 mol% or more of the entire Y.

The value of n represents the molar ratio of the oxide of the trivalent element X and the oxide of the tetravalent element Y. The value of n / 2 is usually 5 or more and 1000 or less, preferably 6 or more and 100 or less, More preferably, it is 6.5 or more and 30 or less, More preferably, it is 7 or more and 10 or less.

The zeolite according to this embodiment may contain a metal element other than the trivalent element X and the tetravalent element Y. Such a case of “containing a metal element” may be either a case where the metal element is present in the framework of the zeolite or a case where the metal element is present outside the framework, and also includes a case where it is a mixture. When the zeolite according to the present embodiment contains other metal elements, the metal elements are not particularly limited, but are usually iron, cobalt, magnesium from the viewpoint of properties in adsorbent applications and catalyst applications. And transition metals belonging to Groups 3 to 12 of the periodic table, such as zinc, copper, palladium, iridium, platinum, silver, gold, cerium, lanthanum, praseodymium, titanium, and zirconium.

When the zeolite according to the present embodiment contains another metal element, the content of the metal element in the zeolite is preferably 0.1 wt% or more and 20 wt% or less, and is 0.3 wt% or more and 10 wt% or less. The following is more preferable. By including other metal elements such as iron and copper, an effect of generating an active site of the catalyst can be obtained. Furthermore, by making the content more than the above lower limit value, an excellent catalytic effect is obtained, and by making the content not more than the above upper limit value, it becomes easy to uniformly disperse the metal element in the zeolite, It is preferable because excellent catalytic activity can be obtained.

The zeolite according to the present embodiment may contain a metal cation such as sodium, potassium or cesium, or a non-metal cation such as ammonium ion (NH ₄ ⁺ ) or hydrogen ion (H ⁺ ). May be. Moreover, you may contain a metallic cation and a nonmetallic cation simultaneously. The cations in the zeolite crystals can be replaced with other ions by ion exchange.

The zeolite according to this embodiment is characterized by having the X-ray powder diffraction pattern shown in Table 2 and FIG. 2 regardless of the presence or absence of other metal elements or metal cations and the presence or absence of ion exchange.

The zeolite according to the present embodiment is a crystalline aluminosilicate porous body having a novel skeleton, has a high aluminum content (for example, Si / Al = 8.0 to 9.1), and contains many ion exchange sites. It is suitable for the development of a catalyst (for example, NOx reduction catalyst) whose key is replacement. The zeolite according to the present embodiment is not particularly limited with respect to its use, but has a specific crystal structure, and therefore is suitably used as a catalyst, an adsorbent, a separation material, and the like. Moreover, since the zeolite which concerns on this embodiment can introduce | transduce a hetero element through dealumination, it may be utilized as a catalyst for manufacture of various basic chemicals.

Furthermore, the zeolite according to this embodiment can be applied as a solid catalyst that promotes the catalytic decomposition of paraffin. Further, the zeolite of the present invention can be isomorphously substituted with a transition metal (titanium, tin, etc.) for a part of the constituent aluminum. For example, zeolite with the same type substitution with titanium is an excellent catalyst for selective oxidation of olefins, paraffins and aromatic rings using oxygen, hydrogen peroxide, alkyl hydroperoxide or the like as an oxidizing agent.

[Method for producing zeolite]
The manufacturing method of the zeolite 100 based on this embodiment is demonstrated. The manufacturing method of the zeolite 100 mainly has a first preparation step, a first heating step, a cooling step, a second preparation step, a second heating step, a drying step, and a third heating step in this order. ing.

<First preparation step>
First, a mixture (gel) of a first silica source, an aluminum source, an alkali source, water, and a structure directing agent (SDA) is prepared.

As the first silica source, for example, one or more of colloidal silica, amorphous silica, sodium silicate, tetraethylorthosilicate, aluminosilicate gel, and the like can be used. Preferably, colloidal silica ((SiO ₂ ) _Ludox , LUDOX (registered trademark)) is used.

As the aluminum source, for example, one or more of aluminum sulfate, sodium aluminate, aluminum hydroxide, aluminum chloride, aluminosilicate gel, metal aluminum and the like can be used. It is also possible to use zeolite such as Y-type zeolite as the aluminum source.

The alkali source is not particularly limited. For example, one or two of sodium hydroxide (NaOH), potassium hydroxide (KOH), lithium hydroxide (LiOH), cesium hydroxide (CsOH), and the like can be used. It is preferable to use the above, and among these, it is more preferable to use sodium hydroxide (NaOH) and potassium hydroxide (KOH).

As the structure directing agent, for example, dimethyldipropylammonium salt is preferable, and dimethyldipropylammonium hydroxide (Me ₂ Pr ₂ NOH) is more preferable. Me and Pr represent a methyl group (CH ₃ ) and a propyl group (CH ₃ CH ₂ CH ₂ ), respectively. A method for producing Me ₂ Pr ₂ NOH will be described later as an example.

<First heating step>
Next, the mixture prepared in the first preparation step is heated with stirring. Specifically, water is partially evaporated to concentrate the mixture to a predetermined amount while stirring the mixture on a hot plate heated to 60 ° C. or higher.

<Cooling process>
Next, the mixture heated in the first heating step is cooled to about room temperature using a water bath. Note that the first heating step and the cooling step can be omitted.

<Second preparation step>
Next, the mixture cooled in the cooling step is re-prepared by adding a second silica source and an alumina source as necessary. As the second silica source and alumina source, Y-type zeolite (SiO ₂ ) _FAU , (Al ₂ O ₃ ) _FAU ) is used. The molar ratio of silicon to aluminum (Si / Al) in the Y-type zeolite is usually from 2.5 to 50, preferably from 3 to 20, more preferably from 3.5 to 10, more preferably from 4 to 6. The following are more preferred, with about 5.3 being most preferred.

In the re-prepared mixture, the content ratio (mol%) of (SiO ₂ ) _{Ludox to} the total silica source ((SiO ₂ ) _Ludox , (SiO ₂ ) _FAU ) is usually 30 to 90%, preferably Is 50 to 80%, more preferably 60 to 75%, and more preferably about 74%. In addition, the content ratio (mol%) of the alkali source (NaOH or the like) to the total silica source in the same mixture is usually 0.05 to 0.6%, preferably 0.1 to 0.5%, more Preferably, the content is 0.2 to 0.4%. When both NaOH and KOH are used, the content ratio of NaOH and KOH is preferably about 0.15%. In addition, the content ratio of the structure directing agent to the total silica source in the same mixture is usually 0.05 to 0.5%, preferably 0.1 to 0.4%, and more preferably 0.15 to 0.00. 3%, most preferably about 0.17%. The content ratio (molar ratio) of (SiO ₂ ) _FAU to the total silica source in the same mixture is usually 10 to 70%, preferably 15 to 50%, more preferably 20 to 35%. Most preferably, it is about%.

So that the above-mentioned _{composition, (SiO 2) Ludox, NaOH} , KOH, for _{H 2} O is such that the content ratios mentioned above, to adjust the amount of mixing in the first preparation step. _{Further, (SiO} 2) _FAU, the _(Al 2 _{O 3) FAU,} as a content ratio described above, it is preferable to adjust the amount of mixing in the second preparation step.

Furthermore, in the re-prepared mixture, the content ratio (molar ratio) of water (H ₂ O) to the total silica source is usually 4 to 50, preferably 5 to 30, more preferably 5.5 to 12, more preferably 6-8, most preferably about 7. By reducing the content ratio of H ₂ O in the mixture in this way, a zeolite having a high organic matter concentration and a large pore volume can be obtained.

<Second heating step>
The mixture (raw material) re-prepared in the second preparation step is usually heated after stirring at room temperature.
The heating here is usually 100 to 200 ° C., preferably 120 to 190 ° C., more preferably 140 to 180 ° C., more preferably 150 to 170 ° C. in a state where the mixture at room temperature is contained in an autoclave. About 160 ° C. is most preferred. In an oven, it is usually performed for 12 hours to 10 days, preferably for 1 to 7 days, standing or stirring.

<Drying process>
Next, the mixture heated in the second heating step is washed and filtered, and further dried. Examples of the drying method include a method in which the washed and filtered mixture is allowed to stand overnight in an oven at about 80 ° C. and a method in which the mixture is dried in the sun.

Through the above steps, an organic composite (powder) containing a crystalline solid of zeolite 100 is obtained.

<Third heating step>
By further heating (baking) the organic composite obtained through the drying step, the organic matter (Me ₂ Pr ₂ NOH used as the structure-directing agent) included can be removed. The heating here is performed at a temperature of about 550 ° C. in a state where the obtained crystalline solid is housed in a muffle furnace. Specifically, the temperature is raised from room temperature to about 550 ° C. at about 1.5 ° C./min, this temperature is maintained for about 6 hours, and then it is allowed to cool.

According to the method for producing zeolite 100 according to the present embodiment, a zeolite having a high aluminum content (Si / Al = 7 to 10) and having a novel skeleton can be obtained. In the method for producing zeolite 100 of the present embodiment, a dimethyldipropylammonium compound is used as a structure-directing agent having a simple structure, and the ratio of water used as a raw material is set to about 6 to 8 of the silica source used as the raw material. About twice as much. As a result, the zeolite can be easily and reliably produced with high purity compared to the case of using a conventional production method in which the ratio of water is about 40 times that of the silica source, and mass production is realized. It becomes easy. Further, since the synthesis of the structure directing agent is simplified, the energy required for the synthesis process can be reduced, and the manufacturing cost can be greatly reduced.

Hereinafter, the effects of the present invention will be made clearer by examples. In addition, this invention is not limited to a following example, In the range which does not change the summary, it can change suitably and can implement.

(Production Example 1)
Production Example 1 of dimethyldipropylammonium hydroxide used as a structure-directing agent for the zeolite of the present invention is shown.

[Step 1]
First, as shown by the following formula, dipropyldimethylammonium was synthesized.

This synthesis was performed by the following procedure. First, 60 mL of dipropylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 350 mL of methanol (manufactured by Wako Pure Chemical Industries, Ltd.) are mixed in a 1 L eggplant flask, and potassium carbonate (manufactured by Wako Pure Chemical Industries, Ltd.) is mixed. ) 90 g was added and stirred at room temperature for 10 minutes.
To this, 68 mL of iodomethane (manufactured by Wako Pure Chemical Industries, Ltd.) was slowly added over 30 minutes, and finally 50 mL of methanol was added.

Next, the mixture was stirred at room temperature for 72 hours, 200 mL of chloroform (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was further stirred at room temperature for 20 minutes.

Next, suction filtration was performed using a glass filter (G4), and the resulting solid was washed with 150 mL of chloroform. The filtrate and the washing solution were combined and placed in a 1 L eggplant flask, and reduced in pressure using an evaporator at 40 ° C. to dryness.

Next, 200 mL of chloroform (manufactured by Wako Pure Chemical Industries, Ltd.) was added to extract the product, and insoluble inorganic salts were removed by suction filtration. The filtrate was taken in a 1 L eggplant flask and again dried under reduced pressure. The product was extracted with 200 mL of chloroform, the inorganic salts were removed by suction filtration, and the clear filtrate was received in a 1 L eggplant flask. The filtrate was dried under reduced pressure, and then 100 mL of benzene (manufactured by Wako Pure Chemical Industries, Ltd.) was added to dry it again.

Next, 150 mL of 2-propanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added and heated on an oil bath at 100 ° C. to dissolve the crude crystals. After allowing to cool, 150 mL of diethyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) was slowly added to reprecipitate the crystals. This was subjected to suction filtration using a glass filter (G3), and the solid was washed with 150 mL of a mixed solution of diethyl ether: 2-propanol = 3: 2 (volume ratio). The obtained crystals were vacuum dried. The yield of the product Me ₂ Pr ₂ NI (dimethyldipropylammonium iodide) was 105.5 g (90% yield).

As NMR analysis values of the product, chemical shift δ obtained when measured by ¹ H NMR (500 MHz, CDCl ₃ ) and measured by ¹³ C NMR (126 MHz, CDCl ₃ ) is shown below.

(I) δ when measured by ¹ H NMR (500 MHz, CDCl ₃ ):
1.07 (6H, t, J = 7.4 Hz, CH ₂ —CH ₂ —CH ₃ )
1.82 (4H, m, CH ₂ —CH ₂ —CDCl ₃ )
3.38 (6H, s, N ⁺ -CH ₃ )
3.54 (4H, m, N ⁺ —CH ₂ —CH ₂ )
(Ii) δ when measured by ¹³ C NMR (126 MHz, CDCl ₃ ):
10.58, 16.40, 51.52, 65.80

[Step 2]
Next, as shown by the following formula, Me ₂ Pr ₂ NI obtained in Step 1 was converted to Me ₂ Pr ₂ NOH (dimethyldipropylammonium hydroxide).

This conversion was performed by the following procedure. First, 75.22 g of dimethyldipropylammonium iodide synthesized in Step 1 was put into a 1 L PP bottle, and then 325.73 g of strongly basic anion exchange resin (SA10A (OH) manufactured by Mitsubishi Chemical Corporation) was added. added. Next, 500 mL of H ₂ O (Milli-Q) was added, the container was shaken lightly, and then allowed to stand in a cool and dark place for 120 hours.

Next, the solution was suction filtered through a glass filter (G4), the resin on the filter was thoroughly washed with 300 mL of H ₂ O (Milli-Q), and the filtrate and the washing solution were combined and concentrated under reduced pressure. The weight of the obtained solution was 133.37 g, and the concentration of Me ₂ Pr ₂ NOH determined by 0.05 M hydrochloric acid titration was 2.097 mmol / g (ion exchange rate 96%). The conversion of Me ₂ Pr ₂ NI to Me ₂ Pr ₂ NOH is just ion exchange, and the NMR spectrum of Me ₂ Pr ₂ NOH is similar to that for Me ₂ Pr ₂ NI.

(Example 1)
A zeolite was synthesized using Me ₂ Pr ₂ NOH obtained in Production Example 1 as a structure-directing agent. This synthesis was performed by the following procedure. First, 16.21 g of Me ₂ Pr ₂ NOH aqueous solution (2.097 mmol / g) obtained in Production Example 1 was taken in a fluororesin (PFA) container having an internal volume of 150 mL, and 9.37 g of NaOH aqueous solution (3.200 mmol). / G), 9.53 g KOH aqueous solution (3.153 mmol / g), 21.39 g Ludox AS-40 (manufactured by Aldrich, containing 41.3 wt% SiO ₂ ) were sequentially added (first preparation step) ).

Next, by stirring for about 3 hours on a hot plate set so that the liquid temperature becomes about 60 ° C., 20.26 g of water (4.41 g of water used for washing in the first preparation step) was obtained. Water) was evaporated (first heating step). After cooling the resulting mixture to room temperature using a water bath (cooling step), 4.99 g of Y-type zeolite (composition H _30.5 Al _30.5 Si _161.5 O ₃₈₄ , Tosoh Corporation) ), HSZ-350HUA, which actually contains 63.9 wt% SiO _2, 10.2 wt% Al ₂ O ₃ , 25.9 wt% H ₂ O in this example) (2nd preparation process), it stirred for 10 minutes at room temperature. The composition of the resulting mixture was 1.0SiO ₂ -0.025Al ₂ O ₃ -0.17Me ₂ Pr ₂ NOH-0.15NaOH-0.15KOH-7H ₂ O, and the total weight of the mixture was 45.64 g. It was.

This mixture was transferred to an autoclave with an inner volume of 125 mL of a fluororesin (PTFE) inner cylinder, and left standing in an oven at 160 ° C. for 165 hours (second heating step). The obtained solid product was collected by filtration and dried overnight in an oven at 80 ° C. (drying step). The weight of the obtained white powder was 6.84 g.

Of this, 5.02 g was placed in an alumina petri dish, heated from room temperature at a rate of 1.5 ° C. per minute in an air atmosphere in a muffle furnace, held at 550 ° C. for 6 hours, and then allowed to cool (third). Heating step (firing step)). In this way, 4.90 g of white powder (after baking) was obtained.

(Example 2)
A zeolite was synthesized using Me ₂ Pr ₂ NOH obtained in Production Example 1 as a structure-directing agent. This synthesis was performed by the following procedure. First, 46.77 g (68.0 mmol) of the Me ₂ Pr ₂ NOH aqueous solution (1.454 mmol / g) obtained in Production Example 1 was put in a fluororesin (PFA) container having an internal volume of 150 mL, and 19.81 g of NaOH. Aqueous solution (3.029 mmol / g, 60.0 mmol), 20.81 g of KOH aqueous solution (2.883 mmol / g, 60.0 mmol), 42.78 g of Ludox AS-40 (Aldrich 41.3 wt% SiO ₂ Therefore, 17.67 g-SiO ₂ , 293.8 mmol-SiO ₂ ) were sequentially added (first preparation step).

Next, by stirring for about 6 hours on a hot plate set to a liquid temperature of about 60 ° C., 53.40 g of water (4.52 g of water used for washing in the first preparation step) Water) was evaporated (first heating step). After cooling the obtained mixture to room temperature using a water bath (cooling step), 9.99 g of Y-type zeolite (composition H _30.5 Al _30.5 Si _161.5 O ₃₈₄ , Tosoh Corporation) ), HSZ-350HUA, # 35UA3502, Si / Al = 5.3, in this example, actually 63.9 wt% SiO ₂ , 10.2 wt% Al ₂ O ₃ , 25.9 wt% H (Containing ₂ O) was added (second preparation step), and the mixture was stirred at room temperature for 10 minutes. The composition of the resulting mixture was 1.0SiO ₂ -0.025Al ₂ O ₃ -0.17Me ₂ Pr ₂ N ⁺ OH ^-- 0.15NaOH-0.15KOH-7.0H ₂ O, the total weight of the mixture was It was 91.28 g.

This mixture was transferred to an autoclave with an inner volume of 125 mL of a fluororesin (PTFE) inner cylinder and allowed to stand in an oven at 160 ° C. for 166 hours (second heating step). The obtained solid product was collected by filtration and dried overnight in an oven at 80 ° C. (drying step). The weight of the obtained white powder was 13.07 g.

2.60 g of this was placed in an alumina petri dish, heated from room temperature at a rate of 1.5 ° C. per minute in an air atmosphere in a muffle furnace, held at 550 ° C. for 6 hours, and then allowed to cool (third Heating step (firing step)). In this way, 2.51 g of white powder (after baking) was obtained.

(Example 3)
A zeolite was synthesized using Me ₂ Pr ₂ NOH obtained in Production Example 1 as a structure-directing agent. This synthesis was performed by the following procedure. First, 58.97 g (68.0 mmol) of the Me ₂ Pr ₂ NOH aqueous solution (1.153 mmol / g) obtained in Production Example 1 was taken in a fluororesin (PFA) container having an internal volume of 150 mL, and 19.81 g of NaOH. Aqueous solution (3.029 mmol / g, 60.0 mmol), 20.82 g KOH aqueous solution (2.883 mmol / g, 60.0 mmol), 42.78 g Ludox AS-40 (Aldrich 41.3 wt% SiO ₂ Therefore, 17.67 g-SiO ₂ , 293.8 mmol-SiO ₂ ) was sequentially added (first preparation step).

Next, by stirring for about 7 hours on a hot plate set so that the liquid temperature becomes about 60 ° C., 65.17 g of water (4.10 g used for washing in the first preparation step) was obtained. Water) was evaporated (first heating step). After cooling the obtained mixture to room temperature using a water bath (cooling step), 9.99 g of Y-type zeolite (composition H _30.5 Al _30.5 Si _161.5 O ₃₈₄ , Tosoh Corporation) ), HSZ-350HUA, # 35UA3502, Si / Al = 5.3, in this example, actually 63.9 wt% SiO ₂ , 10.2 wt% Al ₂ O ₃ , 25.9 wt% H (Containing ₂ O) was added (second preparation step), and the mixture was stirred at room temperature for 10 minutes. The composition of the resulting mixture was 1.0SiO ₂ -0.025Al ₂ O ₃ -0.17Me ₂ Pr ₂ N ⁺ OH ^-- 0.15NaOH-0.15KOH-7.0H ₂ O, the total weight of the mixture was It was 91.28 g.

This mixture was transferred to an autoclave with an inner volume of 125 mL of a fluororesin (PTFE) inner cylinder, and allowed to stand for 95 hours in a 160 ° C. oven at a rotation speed of 20 rpm (second heating step). The obtained solid product was collected by filtration and dried overnight in an oven at 80 ° C. (drying step). The weight of the obtained white powder was 14.10 g.

3.02 g of this was placed in an alumina petri dish, heated from room temperature at a rate of 1.5 ° C. per minute in an air atmosphere in a muffle furnace, held at 550 ° C. for 6 hours, and then allowed to cool (third Heating step (firing step)). In this way, 2.85 g of white powder (after baking) was obtained.

Example 4
A zeolite was synthesized using Sachem Me ₂ Pr ₂ NOH as a structure-directing agent. This synthesis was performed by the following procedure. First, 25.54 g (68.0 mmol) of Me ₂ Pr ₂ NOH aqueous solution (2.663 mmol / g) manufactured by Sachem was taken in a fluorine resin (PFA) container having an internal volume of 150 mL, and 21.04 g of NaOH aqueous solution ( 2.852 mmol / g, 60.0 mmol), 18.80 g of KOH aqueous solution (3.191 mmol / g, 60.0 mmol), 42.78 g of Ludox AS-40 (manufactured by Aldrich, including 41.3 wt% SiO ₂₎ Therefore, 17.67 g-SiO ₂ , 293.8 mmol-SiO ₂ ) was sequentially added (first preparation step).

Next, by stirring for about 3 hours on a hot plate set so that the liquid temperature is about 60 ° C., 29.52 g of water (3.01 g of water used for washing in the first preparation step) was obtained. Water) was evaporated (first heating step). After cooling the obtained mixture to room temperature using a water bath (cooling step), 9.71 g of Y-type zeolite (composition H _30.5 Al _30.5 Si _161.5 O ₃₈₄ , Tosoh Corporation) ), HSZ-350HUA, # 35UA35Y2, Si / Al = 5.5, in this example, actually 68.1 wt% SiO ₂ , 10.5 wt% Al ₂ O ₃ , 21.4 wt% H (Containing ₂ O) was added (second preparation step), and the mixture was stirred at room temperature for 10 minutes. The composition of the resulting mixture was 1.0SiO ₂ -0.025Al ₂ O ₃ -0.17Me ₂ Pr ₂ N ⁺ OH ^-- 0.15NaOH-0.15KOH-7.0H ₂ O, the total weight of the mixture was It was 91.36 g.

This mixture was transferred to an autoclave with an inner volume of 125 mL of a fluororesin (PTFE) inner cylinder, and allowed to stand in an oven at 160 ° C. for 67 hours under a rotation condition of 20 rpm (second heating step). The obtained solid product was collected by filtration and dried overnight in an oven at 80 ° C. (drying step). The weight of the obtained white powder was 13.73 g.

Of this, 3.13 g was placed in an alumina petri dish, heated from room temperature at a rate of 1.5 ° C. per minute in an air atmosphere in a muffle furnace, held at 550 ° C. for 6 hours, and then allowed to cool (third). Heating step (firing step)). In this way, 3.09 g of white powder (after baking) was obtained.

FIG. 2 is a graph showing the analysis result by X-ray diffraction (XRD) of the zeolite of Example 1 obtained by the present inventor. The horizontal axis represents the diffraction angle 2θ [°], and the vertical axis represents the diffraction intensity [cps]. A diffraction spectrum (XRD pattern) obtained by baking and removing organic substances is shown in the upper part, and a diffraction spectrum obtained by the unfired sample is shown in the lower part. From FIG. 2, the lattice spacing d (Å) shown in Table 2 was detected.

X-ray diffraction was measured under the following conditions.
Apparatus used: Ultimate-IV powder X-ray analyzer manufactured by Rigaku Corporation X-ray source: CuKα1 = 1.54057 mm, applied voltage: 40 kV, tube current: 20 mA
Measurement range: 2θ = 2.040 to 52.000 degrees Scanning speed: 2.000 deg. / Min, sampling interval: 0.040 degrees Divergence slit: 1.00 deg, scattering slit: 1.00 deg, light receiving slit: 0.30 mm
Using vertical goniometer and monochromator Measurement method: continuous method, normal method The lattice spacing d is in angstrom units.

As shown in FIG. 2, the diffraction spectra obtained for the samples before and after calcination both have characteristic peaks that are not found in known zeolites. From this result, it can be seen that any sample is a zeolite in which a crystal phase having a novel skeleton structure is formed.

The Si / Al ratio after firing was determined by a calibration curve method (aqueous solution mode) using an inductively coupled plasma atomic emission spectrometer (ICP-9000E manufactured by Shimadzu Corporation). As a result, Si / Al = 9.5.

The nitrogen adsorption of zeolite was measured under the following conditions.
Equipment used: Belsorb max fully automatic adsorption measuring device manufactured by Microtrack Bell Inc. Measurement temperature: -196 ° C
Air bath temperature: 40 ° C
Equilibrium adsorption time: 300 seconds Sample pretreatment conditions: 400 ° C, 2 hours

The nitrogen adsorption measurement results are shown in the graph of FIG. The graph of FIG. 3 shows the adsorption isotherm.
The horizontal axis of the graph represents the relative pressure (ratio between the adsorption equilibrium pressure and the saturated vapor pressure), and the vertical axis represents the nitrogen adsorption amount (cm ³ (STP) / g). S. T.A. P. The term “standard temperature and pressure” means that the adsorption amount is a value converted to a volume (cm ³ ) of 0 ° C. and 1 atm. The lower part of the graph shows the adsorption isotherm before H ⁺ ion exchange, and the upper part of the graph shows the adsorption isotherm after H ⁺ ion exchange. The black circle plot is in the adsorption process, and the white circle plot is in the desorption process.

The BET specific surface area calculated from the lower graph was 434 m ² / g, the outer surface area was 5.1 m ² / g, and the pore volume was 0.173 ml / g. In addition, according to the elemental analysis by ICP-AES of this sample, Si / Al was 9.09. Na / Al and K / Al were 0.12 and 0.52, respectively.

The BET specific surface area calculated from the upper graph was 487 m ² / g, the outer surface area was 6.7 m ² / g, and the pore volume was 0.194 ml / g. In addition, according to the elemental analysis by ICP-AES of this sample, Si / Al was 9.33. Na / Al and K / Al were each less than 0.03.

The ²⁷ Al MAS NMR of the zeolite was measured under the following conditions.
Equipment used: AVANCE III 600 from Bruker
1H resonance frequency: 600 MHz
Rotor rotation speed: 13 kHz
Repeat time: 0.5 sec, integration count: 1024 times

The ²⁹ Si MAS NMR of the zeolite was measured under the following conditions.
Equipment used: AVANCE III 600 from Bruker
1H resonance frequency: 600 MHz
Rotor rotation speed: 10 kHz
Repetition time: 30.0 sec, integration number: 1024 times

^The spectra obtained by ²⁷ Al MAS NMR and ²⁹ Si MAS NMR are shown in the graphs of FIGS. The horizontal axis of each graph represents a chemical shift. The spectrum before firing is shown in the lower part, and the spectrum after firing is shown in the upper part.

In the ²⁷ Al-MAS NMR spectrum after firing in FIG. 4, (1) a major peak with a chemical shift of 56.5 ± 2 ppm and (2) a minor peak existing at 0 ± 2 ppm were observed. The peak (1) is a peak attributed to Al in the skeleton, while the peak (2) is a peak attributed to Al desorbed outside the skeleton. Before firing, the peak of (2) was not observed, and only the peak of (1) was observed.

The three peaks included in the ²⁹ Si-MAS NMR spectrum of FIG. 5 are Si signals corresponding to the coordination forms of Si (2Al), Si (1Al), and Si (0Al) in order from the left side. When Si / Al in the skeleton was estimated from the area ratio of these peaks, it was about 10. Si (nAl) means a Si signal described first from the left in (AlO) _n Si (OSi) _4-n (here, n = 0, 1, 2).

A scanning electron microscope (SEM) photograph of the zeolite of Example 1 was obtained under the following conditions.
Equipment used: JSM-7001F manufactured by JEOL
Acceleration voltage: 1.00 kV or 3.00 kV

The obtained SEM photographs are shown in FIGS. 6A and 6B. 6A (a) to 6 (i) are SEM photographs taken at various magnifications (dimensions to be compared are shown in the figure) from various directions for samples crystallized over 165 hours. This sample corresponds to Example 1. FIG. 6B is a SEM photograph (magnification is the same as FIG. 6A (a)) of a sample crystallized in 45 hours shorter than Example 1.

The zeolite of the present invention can be used as an adsorbent for moisture and the like in air conditioning equipment and heat pumps, and can also be used as a catalyst for synthesis of chemical products and as a purification catalyst for automobile exhaust gas and the like.

100 Zeolite 101 (101a, 101b) Oxygen 8- membered ring 101A, 101B, 102A Group 101C Row 102 Oxygen 12-membered ring

Claims (8)

1. As measured by the powder X-ray diffraction method, it has an X-ray diffraction pattern including at least the lattice spacing d (Å) and relative intensity shown in Table 1 below,
   The said relative intensity | strength has shown the ratio of the intensity | strength of the other peak with respect to the intensity | strength of the largest peak among the peaks contained in the said X-ray-diffraction pattern, The zeolite characterized by the above-mentioned.
   

   
2. The zeolite according to claim 1, wherein the pore volume estimated by nitrogen adsorption measurement is 0.12 ml / g or more and 0.25 ml / g or less.
3. A plurality of oxygen 8-membered rings and oxygen 12-membered rings independent of each other;
   The plurality of oxygen 8-membered rings are divided into a plurality of groups, and in each group, the oxygen 8-membered rings overlap so as to have a common through hole in one direction,
   The plurality of oxygen 12-membered rings are divided into a plurality of groups, and in each group, the oxygen 12-membered rings overlap so as to have a common through hole in a direction parallel to one plane,
   3. The zeolite according to claim 1, wherein an overlapping direction of the oxygen 8-membered ring and an overlapping direction of the oxygen 12-membered ring intersect each other.
4. In the oxygen eight-membered ring, in one direction intersecting with the overlapping direction, a pair and an isolated one are connected so as to form a line in an alternating manner, and the lines form a pair. The zeolite according to claim 3, wherein the oxygen 8-membered ring and the isolated oxygen 8-membered ring are connected so as to be adjacent to each other.
5. The zeolite according to any one of claims 3 and 4, wherein the oxygen 12-membered ring is connected side by side at equal intervals in two directions in a plane intersecting the overlapping direction.
6. The pore diameter of the oxygen 8-membered ring is 0.295 nm or more and 0.454 nm or less when subtracting the length of two ionic radii (0.135 nm) of oxygen, and 0.565 nm or more and 0.724 nm or less when not subtracting, The pore diameter of the oxygen 12-membered ring is 0.595 nm to 0.710 nm when subtracting the length of two oxygen ionic radii (0.135 nm), and 0.865 nm to 0.980 nm when not subtracting. The zeolite according to any one of claims 3 to 5, which is characterized by the following.
7. The zeolite according to any one of claims 1 to 6, wherein the number density of T atoms contained is 15 / nm ³ or more and 18 / nm ³ or less.
8. A method for producing a zeolite according to any one of claims 1 to 7,
   A first preparation step of preparing a mixture of a first silica source, an alkali source, water, and a structure-directing agent while stirring;
   A first heating step of heating the prepared mixture while stirring;
   A cooling step for cooling the heated mixture;
   A second preparation step of adding a second silica source and an alumina source to the cooled mixture and re-adjusting the mixture while stirring;
   A second heating step for heating the re-prepared mixture;
   A drying step of drying the heated mixture after washing and filtering;
   A third heating step for heating the organic composite obtained through the drying step and removing the organic matter included in the inclusion;
   A method for producing zeolite, wherein colloidal silica is used as the first silica source, Y-type zeolite is used as the second silica source and alumina source, and a dimethyldipropylammonium compound is used as the structure-directing agent.

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