Zeolite

Abstract

The purpose of the present invention is to provide at least one of: zeolite which has an oxygen 10-membered ring structure, the zeolite being able to increase the p-xylene selectivity in the production of xylene by modification of an alcohol and being applicable to industrial processes at low cost; an alcohol modification catalyst containing the same; and a method for producing xylene using the same.　This zeolite has an oxygen 10-membered ring structure, contains one or more elements selected from the group consisting of magnesium, calcium, titanium, boron and phosphorus, and has a total pore volume of 0.21 cm3 / g or less.

Description

Zeolite

[0001] The present disclosure relates to zeolites containing certain elements.

[0002] One method for producing p-xylene, a raw material for terephthalic acid, is by reforming methanol using a specific metal-containing zeolite having a 10-membered oxygen ring structure as a catalyst.

[0003] For example, Non-Patent Document 1 discloses that aromatic hydrocarbons including p-xylene can be obtained by reforming methanol using zinc-containing ZSM-5 (MFI type zeolite) as a catalyst.

[0004] Furthermore, Patent Document 1 discloses a method for co-producing p-xylene and ethylene propylene from toluene and methanol using, as a catalyst, an MFI-type zeolite modified with silicon using an organosilicon precursor.

[0005] Special Publication No. 2017-518995

[0006] Catalysis Today, Volume 233, 2014, Pages 8-13

[0007] In the alcohol reforming methods described in Patent Document 1 and Non-Patent Document 1, not only p-xylene but also aromatic hydrocarbons other than p-xylene are simultaneously produced. Although it is easy to separate xylene from aromatic hydrocarbons, the separated xylene is a mixture of xylene isomers, namely p-xylene, o-xylene, and m-xylene. Separating and purifying only the target p-xylene from such a mixture of xylene isomers requires a large amount of energy. Therefore, in the production of xylene by alcohol reforming, it is desirable to have a high ratio of p-xylene to the xylenes produced. However, in the method of Non-Patent Document 1, the ratio of p-xylene to the xylenes produced (hereinafter also referred to as "p-xylene selectivity") was low.

[0008] On the other hand, while Patent Document 1 has a higher p-xylene selectivity than Non-Patent Document 1, it requires the use of a large amount of an expensive organosilicon precursor to silicon-modify the MFI zeolite. In addition, it is unavoidable to produce waste liquid containing organosilicon, which requires equipment to remove the waste liquid containing organosilicon. Therefore, the production cost of the production method of Patent Document 1 is high, making it difficult to apply to industrial processes.

[0009] The present disclosure aims to provide at least one of a zeolite having a 10-membered oxygen ring structure that can increase p-xylene selectivity in the production of xylene by alcohol reforming and that can be adapted to industrial processes at low cost, an alcohol reforming catalyst containing the same, and a method for producing xylene using the same.

[0010] The present inventors have focused on zeolite catalysts and investigated their structures and compositions in order to improve p-xylene selectivity in the production of xylene by alcohol reforming. As a result, they have found that the ratio of p-xylene to the total xylenes produced (p-xylene selectivity) can be increased by incorporating predetermined elements into a zeolite having a 10-membered oxygen ring structure and by controlling the total pore volume to a predetermined value or less.

[0011] That is, the present invention is as described in the claims, and the gist of the present disclosure is as follows: [1] A porous silica sintered body containing one or more predetermined elements selected from the group consisting of magnesium, calcium, titanium, boron, and phosphorus, and having a total pore volume of 0.21 cm ３ / g or less. [2] The zeolite having a 10-membered oxygen ring structure according to [1], wherein the zeolite having a 10-membered oxygen ring structure is MFI zeolite, MEL zeolite, TON zeolite, STF zeolite, MTT zeolite, MWW zeolite, or ZSM-48 zeolite. [3] The zeolite according to [1] or [2], characterized in that the molar ratio of silica to alumina is 10 or more and 250 or less. [4] The zeolite according to any one of [1] to [3], further containing one or more other elements selected from the group consisting of silver, zinc, gallium, and iron. [5] The zeolite according to any one of [1] to [4], wherein the predetermined element is supported at least on the outer surface. [6] In the difference spectrum obtained by subtracting the IR spectrum of the zeolite before 2,6-di-tert-butylpyridine adsorption from the IR spectrum of the zeolite to which 2,6-di-tert-butylpyridine has been adsorbed, －１ 1620cm or more －１ 1630 cm for the maximum intensity of the peak having a peak top in the range －１ More than 1650cm －１ [7] The zeolite according to any one of [1] to [5], wherein the ratio of the maximum intensity of the peaks having peak tops in the following ranges is greater than 1.5: [7] A zeolite having a treatment temperature of 420°C, a treatment pressure (gauge pressure) of 0.2 MPa, a treatment time of 6 hours, and a methanol weight hourly space velocity of 1.0 Hr －１

[10] A method for producing benzene, xylene, and toluene simultaneously, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[11] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[12] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[13] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[14] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[15] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[16] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[17] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[18] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[19] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to [7] with a fluid containing an alcohol.

[20] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to

[20] with a fluid containing an alcohol.

[21] A method for producing xylene from alcohol, comprising contacting the zeolite according to any one of [1] to

[20] with a fluid containing an alcohol.

[22] A method for producing xylene from alcohol, comprising contacting the zeolite according to ３

[12] Use of a zeolite having a 10-membered oxygen ring structure for co-producing benzene, xylene, and toluene from alcohol, wherein the zeolite contains one or more predetermined elements selected from the group consisting of magnesium, calcium, titanium, boron, and phosphorus, and has a total pore volume of 0.21 cm 3 or less. ３ / g or less, use.

[0012] The present disclosure can provide at least one of a zeolite that can increase p-xylene selectivity in the production of xylene by alcohol reforming, an alcohol reforming catalyst containing the same, and a xylene production method using the same.

[0013] The terms used in this embodiment are as follows:

[0014] An "aluminosilicate" is a composite oxide having a structure consisting of a repeating network of aluminum (Al) and silicon (Si) via oxygen (O). Among aluminosilicates, those that have a crystalline XRD peak in their powder X-ray diffraction (hereinafter also referred to as "XRD") pattern are "crystalline aluminosilicates," and those that do not have a crystalline XRD peak are "amorphous aluminosilicates."

[0015] In this embodiment, the XRD pattern can be obtained by XRD measurement under the following conditions: Acceleration current / voltage: 10 mA / 30 kV Radiation source: CuKα radiation (λ=1.54178 Å) Measurement mode: Continuous scan Scan condition: 2° / min Measurement range: 2θ=10 to 70° Scattering slit: 1 / 3° Divergence slit: 1 / 3° Receiving slit: 0.3 mm Filter: Ni filter

[0016] The XRD pattern can be measured using a general powder X-ray diffractometer (e.g., Ultima IV Protectus, manufactured by Rigaku Corporation). The crystalline XRD peak is a peak detected by identifying the 2θ of the peak top in an analysis of the XRD pattern using general analysis software (e.g., IGOR Pro 8, manufactured by WaveMetrics), and an example of such a peak is an XRD peak having a half-width of 2θ = 0.50° or less.

[0017] "Zeolite" is a compound having a regular structure in which skeletal atoms (hereinafter also referred to as "T atoms") are arranged via oxygen (O), and the T atoms are at least one of metal atoms and metalloid atoms. Examples of metal atoms include one or more selected from the group consisting of aluminum (Al), titanium (Ti), iron (Fe), zinc (Zn), gallium (Ga), and tin (Sn), with aluminum being preferred. Examples of metalloid atoms include one or more selected from the group consisting of boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te), with silicon being preferred. Note that zeolites in which the T atoms are essentially composed of aluminum (Al) and silicon (Si) are classified as crystalline aluminosilicates. Here, the expression "T atoms substantially consisting of aluminum (Al) and silicon (Si)" does not only mean that the T atoms consist only of aluminum (Al) and silicon (Si), but also means that the T atoms may contain T atoms other than aluminum (Al) and silicon (Si) as long as the effects of the present invention are achieved.

[0018] A "zeolite-like substance" is a compound having a regular structure in which T atoms are oxygen-mediated, and which contains at least an atom other than a metal or a metalloid in the T atom. Examples of zeolite-like substances include complex phosphorus compounds containing phosphorus (P) as the T atom, such as aluminophosphate (AlPO) and silicoaluminophosphate (SAPO).

[0019] The "regular structure (hereinafter also referred to as "skeletal structure")" of zeolite and zeolite-like substances refers to a skeletal structure specified by the skeletal structure code (hereinafter also simply referred to as "skeletal code") established by the Structure Commission of the International Zeolite Association, and a skeletal structure (hereinafter also referred to as "intergrowth structure") having a crystal polymorph described on the International Zeolite Association's website, "http: / / www.iza-structure.org / databases / ." For example, "MFI zeolite" is a zeolite having a skeletal structure specified by the skeletal code "MFI." Furthermore, for example, "ZSM-48 zeolite" is a zeolite having an intergrowth structure composed of an intergrowth of polymorphs ZSM-48_A and ZSM-48_B. The intergrowth structure in this embodiment is not particularly limited in terms of the ratio of polymorphs (hereinafter also referred to as "intergrowth ratio"), and includes intergrowth structures with any intergrowth ratio.

[0020] The zeolite framework structure (intergrowth structure) can be identified by comparison with the XRD patterns (hereinafter also referred to as "reference patterns") of each framework structure listed in the Zeolite Framework on the IZA Structure Committee's homepage at http: / / www.iza-structure.org / databases / . With regard to the structure of zeolites, the terms framework structure (intergrowth structure), crystalline structure, and crystalline phase are used interchangeably.

[0021] A "zeolite having a 10-membered oxygen ring structure" is a zeolite that contains a ring with 10 oxygen atoms (hereinafter also referred to as a "10-membered oxygen ring") as a ring (pore) formed by the T atoms and oxygen atoms that constitute the skeletal structure. A "zeolite having a 10-membered oxygen ring structure" may be a zeolite in which the ring formed in the skeletal structure is composed only of 10-membered oxygen rings, or may be a zeolite that includes rings other than the 10-membered oxygen rings in addition to the 10-membered oxygen rings. Hereinafter, a zeolite having a 10-membered oxygen ring structure will also be referred to as a 10-membered oxygen ring zeolite.

[0022] "Xylene" is a general term for p-xylene, o-xylene and m-xylene, and unless otherwise specified, means one or more selected from the group consisting of p-xylene, o-xylene and m-xylene.

[0023] SiO ２ / Al ２ O ３ The composition in this embodiment, such as the ratio, the content of a predetermined element, and the content of other elements, can be determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES) using a general inductively coupled plasma atomic emission spectrometer (ICP device) (for example, OPTIMA 5300DV, manufactured by PerkinElmer). Note that for composition analysis, a sample solution prepared by dissolving a sample in a mixed aqueous solution of hydrofluoric acid and nitric acid can be used.

[0024] Zeolites according to the present disclosure will be described below by way of an example embodiment. The present disclosure includes any combination of the configurations and parameters disclosed herein, and the upper and lower limits of the values ​​disclosed herein include any combination.

[0025] The zeolite of this embodiment is a 10-membered oxygen ring zeolite, contains one or more elements selected from the group consisting of magnesium, calcium, titanium, boron, and phosphorus, and has a total pore volume of 0.21 cm ３ / g or less.

[0026] The zeolite of the present embodiment may be any 10-membered oxygen ring zeolite. From the viewpoint of further increasing the p-xylene selectivity, however, MFI zeolite, MEL zeolite, TON zeolite, STF zeolite, MTT zeolite, MWW zeolite, or ZSM-48 zeolite is preferred, MFI zeolite or MEL zeolite is more preferred, and MFI zeolite is even more preferred.

[0027] In the zeolite of this embodiment, the T atoms constituting the framework structure are not particularly limited as long as they are composed of at least either metal atoms or metalloid atoms, but from the viewpoint of further increasing the p-xylene selectivity, they are preferably composed substantially of aluminum (Al) and silicon (Si). In other words, the zeolite of this embodiment is preferably a crystalline aluminosilicate having a 10-membered oxygen ring structure.

[0028] The zeolite of the present embodiment contains one or more elements selected from the group consisting of magnesium, calcium, titanium, boron, and phosphorus (hereinafter also referred to as "predetermined elements"). Among magnesium, calcium, titanium, boron, and phosphorus, the predetermined element contained in the zeolite of the present embodiment is preferably at least one of magnesium, calcium, and phosphorus, more preferably at least one of magnesium and calcium, and even more preferably magnesium, from the viewpoint of further increasing p-xylene selectivity.

[0029] The state of the predetermined element contained in the zeolite of the present embodiment is not particularly limited, but examples thereof include a compound (e.g., oxide), a metal (or an element), an ion, an alloy, or two or more of these.

[0030] In the zeolite of this embodiment, the content of a predetermined element relative to 100% by mass of the dry mass of the zeolite of this embodiment (hereinafter also referred to as the "predetermined element content") is not particularly limited, but from the viewpoint of further increasing the p-xylene selectivity, it is preferably 2% by mass or more, more preferably 4% by mass or more, and even more preferably 6% by mass or more. Furthermore, from the viewpoint of further increasing the p-xylene selectivity, the content of the predetermined element in the zeolite of this embodiment is preferably 12% by mass or less, and more preferably 10% by mass or less. The upper and lower limit values ​​of the predetermined element content may be any combination of the above-mentioned upper and lower limit values, but are preferably 2% by mass or more and 12% by mass or less, more preferably 4% by mass or more and 12% by mass or less, and even more preferably 6% by mass or more and 10% by mass or less. In this embodiment, the dry mass is the mass of the zeolite after heat treatment in air at 600°C for 60 minutes.

[0031] In addition, the above-mentioned content of the specified element refers to the total content of the two or more elements when the specified element is two or more elements, and refers to the content of the element alone when the specified element is one element.

[0032] The form in which the predetermined element is contained in the zeolite of this embodiment is not particularly limited; however, from the viewpoint of further increasing p-xylene selectivity, it is preferable that the predetermined element be supported on the zeolite. Note that, in this embodiment, "containing the predetermined element" means that the predetermined element is contained in the zeolite, and the predetermined element may be contained in any state and at any site. On the other hand, "supporting the predetermined element" means that the predetermined element is contained as a component other than the T atom of the zeolite. Examples of the form in which the predetermined element is supported include a form in which the predetermined element is supported on at least one of the outer surface of the zeolite (the surface of the zeolite excluding the inner surfaces of the pores) and the inner surfaces of the pores. From the viewpoint of further increasing p-xylene selectivity, it is preferable that the predetermined element be supported on at least the outer surface of the zeolite, and it is more preferable that the predetermined element be supported on both the outer surface of the zeolite and the inner surfaces of the pores.

[0033] Although the reason why the p-xylene selectivity is further increased by supporting a predetermined element at least on the outer surface of the zeolite is not clear, it is believed that the predetermined element supported on the outer surface of the zeolite interacts with the acid sites on the outer surface of the zeolite, making it difficult for the alcohol reforming reaction at the acid sites on the outer surface of the zeolite to proceed, thereby reducing the proportion of xylene produced at the acid sites on the outer surface of the zeolite and increasing the proportion of xylene produced at acid sites inside the zeolite. Xylene produced at acid sites inside the zeolite is discharged through pores (rings) formed in the zeolite, and it is presumed that, as described below, the zeolite of this embodiment makes it difficult for o-xylene and m-xylene to be discharged from the pores, while p-xylene is easily discharged from the pores. Therefore, it is believed that an increase in the proportion of xylene produced at acid sites inside the zeolite increases the proportion of xylene discharged through pores (rings) that preferentially discharge p-xylene, thereby further improving p-xylene selectivity.

[0034] The zeolite of this embodiment has a total pore volume of 0.21 cm ３ / g or less. The total pore volume is the volume of pores per unit mass of the zeolite. The total pore volume of the zeolite of this embodiment is calculated from the equilibrium relative pressure (hereinafter referred to as "p / p") from the nitrogen adsorption / desorption isotherm of the zeolite. ０ ") is 0.990. ３ ) and then substitute the adsorption amount V into the following formula (1) to calculate the total pore volume (cm ３ / g) = V × 1.547 × 10 －３ ...(1)

[0035] The nitrogen adsorption / desorption isotherm for determining the adsorption amount V in the above formula (1) can be obtained by a constant volume method in which nitrogen gas is adsorbed into zeolite while changing the pressure and the amount is measured. For measurements by the constant volume method, a general nitrogen adsorption device (for example, BELSORP-mini II, manufactured by Microtrac-Bell) can be used, and the following measurement conditions can be used: Measurement temperature: -196°C Zeolite pretreatment: 350°C, vacuum drying for 2 hours

[0036] In the zeolite of this embodiment, the lower limit of the total pore volume is 0 cm ３ / g, but from the viewpoint of further increasing the p-xylene selectivity, ３ / g or more, and ３ That is, from the viewpoint of further increasing the p-xylene selectivity, the total pore volume of the zeolite of the present embodiment is more preferably 0.05 cm3 / g or more. ３ / g or more 0.21cm ３ / g or less, and ３ / g or more 0.21cm ３ It is more preferable that the SiO2 content is 1 / g or less.

[0037] In the zeolite of this embodiment, the molar ratio of silica to alumina (hereinafter referred to as "SiO ２ / Al ２ O ３ The SiO ratio is not particularly limited, but from the viewpoint of further increasing the p-xylene selectivity, it is preferably 250 or less, more preferably 200 or less, and even more preferably 100 or less. ２ / Al ２ O ３ From the viewpoint of further increasing the p-xylene selectivity, the ratio is preferably 10 or more, more preferably 20 or more, and even more preferably 30 or more. ２ / Al ２ O ３ The upper and lower limit values ​​of the ratio may be any combination of the upper and lower limit values ​​described above, but from the viewpoint of further increasing the p-xylene selectivity, the ratio is preferably from 10 to 250, more preferably from 10 to 200, even more preferably from 10 to 100, particularly preferably from 20 to 100, and most preferably from 30 to 100.

[0038] In addition to the predetermined elements described above, the zeolite of the present embodiment may further contain other elements (hereinafter simply referred to as "other elements") different from the predetermined elements. The other elements that can be contained in the zeolite of the present embodiment are preferably one or more elements selected from the group consisting of silver, zinc, gallium, and iron. By containing these other elements in addition to the predetermined elements, the zeolite of the present embodiment can not only increase the p-xylene selectivity but also increase the total yield of benzene, xylene, and toluene, which are useful as chemical raw materials (hereinafter also referred to as "BTX yield"). The BTX yield can be calculated by multiplying the ratio of the total number of moles (mol) of carbon atoms contained in benzene, xylene, and toluene in the reaction product to the total number of moles (mol) of carbon atoms contained in the reaction product (all components contained in the reaction product) obtained by reforming alcohol, by the alcohol conversion rate (%).

[0039] When the zeolite of the present embodiment contains other elements, the combination of the contained specified elements and the other elements is arbitrary; however, from the viewpoint of further increasing the BTX yield while increasing the p-xylene selectivity, a combination of one or more specified elements selected from the group consisting of magnesium, calcium, and phosphorus and one or more other elements selected from the group consisting of zinc and gallium is preferred, a combination of one or more specified elements selected from the group consisting of magnesium and calcium and one or more other elements selected from the group consisting of zinc and gallium is more preferred, a combination of one or more specified elements selected from the group consisting of magnesium and calcium and zinc (other elements) is even more preferred, and a combination of magnesium (specified elements) and zinc (other elements) is particularly preferred.

[0040] The state of the other elements that can be contained in the zeolite of the present embodiment is not particularly limited, but examples thereof include a compound (e.g., an oxide), a metal (or an element), an ion, an alloy, or two or more of these states.

[0041] In the zeolite of the present embodiment, the content of other elements relative to 100% by mass of the dry mass of the zeolite of the present embodiment (hereinafter also referred to as "other element content") is not particularly limited, but from the viewpoint of further increasing the BTX yield while increasing the p-xylene selectivity, the content is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more. Furthermore, from the viewpoint of further increasing the BTX yield while increasing the p-xylene selectivity, the content of other elements in the zeolite of the present embodiment is preferably 12% by mass or less, more preferably 10% by mass or less, and even more preferably 3% by mass or less. The upper and lower limit values ​​for the content of other elements may be any combination of the upper and lower limit values ​​described above; from the viewpoint of further increasing the BTX yield while increasing the p-xylene selectivity, the content is preferably 0.1% by mass or more and 12% by mass or less, more preferably 0.3% by mass or more and 10% by mass or less, even more preferably 0.3% by mass or more and 3% by mass or less, and particularly preferably 0.5% by mass or more and 3% by mass or less.

[0042] The aforementioned content of other elements refers to the total content of the two or more elements when the other elements are two or more elements, and refers to the content of the element alone when the other element is one element.

[0043] The form in which the other elements may be contained in the zeolite of the present embodiment is not particularly limited, but from the viewpoint of further increasing the BTX yield while increasing the p-xylene selectivity, the other elements are preferably supported on the zeolite. Examples of the form in which the other elements are supported include a form in which the other elements are supported on at least one of the outer surface and the inner surfaces of the pores of the zeolite, a form in which the other elements are supported on at least both the outer surface and the inner surfaces of the pores of the zeolite is preferred, and a form in which the other elements are supported on the inner surfaces of the pores of the zeolite is more preferred.

[0044] The reason why the BTX yield is further increased by supporting another element at least on the inner surfaces of the pores of the zeolite is not clear, but it is thought that the other element supported on the inner surfaces of the pores of the zeolite interacts with the acid sites on the inner surfaces of the pores of the zeolite to promote the reforming reaction of alcohols to aromatic compounds at the acid sites on the inner surfaces of the pores of the zeolite, and as a result, the proportion of BTX produced at the acid sites on the inner surfaces of the pores of the zeolite increases, thereby further improving the BTX yield.

[0045] As described above, the zeolite of the present embodiment preferably has predetermined elements and other elements supported on its outer surface. However, the fact that metal elements (metal elements as predetermined elements and metal elements as other elements) are supported on the outer surface of the zeolite can be seen from the presence of a peak at 1630 cm in a difference spectrum (hereinafter also referred to as the "difference spectrum") obtained by subtracting the IR spectrum of the zeolite before 2,6-di-tert-butylpyridine adsorption (hereinafter also referred to as the "background spectrum") from the IR spectrum of the zeolite to which 2,6-di-tert-butylpyridine has been adsorbed (hereinafter also referred to as the "adsorption spectrum"). －１ More than 1650cm －１ A peak having a peak top in the following range (hereinafter referred to as "p(1630 cm)") －１ ~1650cm －１ This can be confirmed by the presence of a '.

[0046] In addition, p (1630 cm －１ ~1650cm －１ ) is a peak attributed to 2,6-di-tert-butylpyridine adsorbed on the metal element supported on the zeolite. 2,6-di-tert-butylpyridine cannot penetrate into the interior of the 10-membered oxygen ring zeolite due to its molecular size. Therefore, p (1630 cm －１ ~1650cm －１ ) can be said to be a peak attributed to 2,6-di-tert-butylpyridine adsorbed on the metal element supported on the outer surface of the zeolite. －１ ~1650cm －１ ) is preferably 1635 cm －１Over 1645cm －１ It has a peak top in the following range.

[0047] Here, 1600 cm in the difference spectrum －１ 1620cm or more －１ A peak having a peak top in the following range (hereinafter referred to as "p(1600 cm)" －１ ~1620cm －１ ) is a peak attributed to 2,6-di-tert-butylpyridine adsorbed on the acid sites (protonic acid sites) present on the outer surface of the zeolite. Therefore, p (1600 cm －１ ~1620cm －１ ) maximum intensity (height intensity) relative to p (1630 cm －１ ~1650cm －１ The ratio of the maximum intensity (height intensity) of p (1600 cm) to the maximum intensity (height intensity) of p (1600 cm) (hereinafter also referred to as "IR peak ratio") is an index representing the ratio of the amount of metal elements to the amount of acid sites on the outer surface of the zeolite. －１ ~1620cm －１ ) is preferably 1605 cm －１ Over 1615cm －１ The peak tops are as follows: Furthermore, the maximum intensity (height intensity) means the intensity at the peak top.

[0048] In the zeolite of this embodiment, the IR peak ratio may be 0 or greater and is not particularly limited. However, from the viewpoint of further increasing p-xylene selectivity, it is preferably 1.4 or greater, more preferably greater than 1.5, and even more preferably 1.6 or greater. In the zeolite of this embodiment, the IR peak ratio may be 0 or greater and is not particularly limited. However, from the viewpoint of further increasing p-xylene selectivity, it is preferably 5.0 or less, more preferably 4.0 or less, and even more preferably 3.6 or less. The upper and lower limits of the IR peak ratio may be any combination of the above-mentioned upper and lower limits. From the viewpoint of further increasing p-xylene selectivity, it is preferably 1.4 or greater and 5.0 or less, more preferably greater than 1.5 and 5.0 or less, even more preferably greater than 1.5 and 4.0 or less, particularly preferably 1.6 or greater and 4.0 or less, and most preferably 1.6 or greater and 3.6 or less.

[0049] The reason why the p-xylene selectivity is increased when the IR peak ratio is in the above-mentioned range is not clear, but it is presumed that the IR peak ratio in the above-mentioned range facilitates interaction between the metal elements and the acid sites on the outer surface of the zeolite, further increasing the proportion of xylene produced at the acid sites inside the zeolite, and thereby further increasing the p-xylene selectivity.

[0050] The background spectrum and the adsorption spectrum can be measured using an FT-IR device (for example, FT / IR-6600, manufactured by JASCO Corporation). In measuring the background spectrum, the measurement sample (zeolite) is placed in a disk shape (approximately 10 mg / cm ２) and filled into a thermal transmission cell, which is then pretreated under vacuum at 450°C for 2 hours. After pretreatment, the temperature is lowered to 200°C under vacuum conditions, and the background spectrum is measured under the following measurement conditions. In measuring the adsorption spectrum, for example, 2,6-di-tert-butylpyridine is introduced into the thermal transmission cell after measuring the background spectrum, and the measurement sample is brought into contact with 2,6-di-tert-butylpyridine under conditions of 200°C, 30 minutes, and 100 Pa. Thereafter, the thermal transmission cell is treated under vacuum at 200°C for 30 minutes, and excess 2,6-di-tert-butylpyridine is removed, after which the adsorption spectrum is measured under the following measurement conditions. Measurement method: thermal transmission method Measurement temperature: 200°C Measurement wavelength range: 800 to 4000 cm-1 Resolution: 2 cm-1 Number of accumulations: 128 Measurement atmosphere: vacuum

[0051] The zeolite of the present embodiment preferably does not contain a structure directing agent (hereinafter also referred to as "SDA") derived from the raw materials for production thereof (i.e., the SDA content in the zeolite of the present embodiment is 0 mass%), since this makes it easier to improve p-xylene selectivity. However, the zeolite of the present embodiment may contain an SDA within a range in which the object of the present invention can be achieved. The SDA content in the zeolite of the present embodiment may be 0 mass% or more and 10 mass% or less, more than 0 mass% and 5 mass% or less, or even 1 mass% or more and 0.5 mass% or less, relative to 100 mass% of the zeolite of the present embodiment. In the present embodiment, a content of 0 mass% or 0 mol% means that the component is substantially not contained, and "substantially not containing the component" means that the component is not detected (below the measurement limit).

[0052] The zeolite of the present embodiment described above can be used in the production of xylene by reforming alcohol, and can be used as an alcohol reforming catalyst for reforming alcohol into xylene. The alcohol reforming catalyst contains at least the zeolite of the present embodiment. By using the zeolite of the present embodiment in the production of xylene by reforming alcohol, the ratio of p-xylene to the xylenes produced (p-xylene selectivity) can be increased. Note that in the method for producing xylene by reforming alcohol, aromatic hydrocarbons other than xylene (for example, benzene or toluene) may be co-produced in addition to xylene.

[0053] The method for producing xylene by alcohol reforming includes a step of contacting the zeolite of the present embodiment with a fluid containing alcohol (hereinafter also referred to as an "alcohol-containing fluid") (hereinafter also referred to as a "contacting step"). A specific example of a method for contacting the zeolite of the present embodiment with the alcohol-containing fluid is a method in which the zeolite of the present embodiment is packed into a stationary phase flow reactor to form a packed bed, and the alcohol-containing fluid is passed through this packed bed.

[0054] In the method for producing xylene by reforming alcohol, the reforming reaction of alcohol proceeds by contacting the zeolite of the present embodiment with an alcohol-containing fluid, and therefore the contact conditions for contacting the zeolite of the present embodiment with the alcohol-containing fluid are not particularly limited. Preferred contact conditions include the following:

[0055] The contact temperature between the zeolite of this embodiment and the alcohol-containing fluid is preferably 300°C or higher, and more preferably 350°C or higher, from the viewpoint of further increasing the p-xylene selectivity. Furthermore, the contact temperature between the zeolite of this embodiment and the alcohol-containing fluid is preferably 550°C or lower, and more preferably 500°C or lower, from the viewpoint of further increasing the p-xylene selectivity. The upper and lower limit values ​​of the contact temperature may be any combination of the above-mentioned upper and lower limit values, but from the viewpoint of further increasing the p-xylene selectivity, the temperature is preferably 300°C or higher and 550°C or lower, more preferably 350°C or higher and 550°C or lower, and even more preferably 350°C or higher and 500°C or lower.

[0056] The pressure (gauge pressure) at which the zeolite of this embodiment is brought into contact with the alcohol-containing fluid is preferably 0.05 MPa or more, and more preferably 0.1 MPa or more, from the viewpoint of further increasing the p-xylene selectivity. Furthermore, the pressure (gauge pressure) at which the zeolite of this embodiment is brought into contact with the alcohol-containing fluid is preferably 1 MPa or less, and more preferably 0.5 MPa or less, from the viewpoint of further increasing the p-xylene selectivity. The upper and lower limit values ​​of the contact pressure (gauge pressure) may be any combination of the upper and lower limit values ​​described above, but from the viewpoint of further increasing the p-xylene selectivity, it is preferably 0.05 MPa or more and 1 MPa or less, more preferably 0.05 MPa or more and 0.5 MPa or less, and even more preferably 0.1 MPa or more and 0.5 MPa or less. The gauge pressure is a pressure obtained by setting atmospheric pressure to 0 MPa.

[0057] The weight hourly space velocity (WHSV) of the alcohol in the alcohol-containing fluid brought into contact with the zeolite of this embodiment is 0.05 hr from the viewpoint of further increasing the p-xylene selectivity. －１ It is preferable that the time is 0.5 hours or more. －１ In addition, from the viewpoint of further increasing the p-xylene selectivity, the weight hourly space velocity (WHSV) of the alcohol in the alcohol-containing fluid brought into contact with the zeolite of this embodiment is preferably 10 hr or more. －１ Preferably, it is 5 hours or less.－１ The upper and lower limits of the weight hourly space velocity (WHSV) of the alcohol may be any combination of the upper and lower limits described above, but from the viewpoint of further increasing the p-xylene selectivity, it is more preferable that the WHSV is 0.05 hr or less. －１ Over 10 hours －１ Preferably, it is 0.05 hr or less. －１ Over 5 hours －１ More preferably, it is 0.5 hours or less. －１ Over 5 hours －１ It is even more preferable that the WHSV is equal to or less than 1. The WHSV is a parameter that represents the amount of alcohol supplied per unit mass of zeolite per hour (the amount of alcohol supplied in liquid form) ([g (zeolite)] / [g (alcohol) / h] (=[hr －１ ])).

[0058] The contact time between the zeolite of this embodiment and the alcohol-containing fluid can be appropriately set depending on the amount of p-xylene to be obtained.

[0059] The alcohol-containing fluid used in the contact step may be a fluid consisting of only alcohol, or may be a fluid containing alcohol and a component other than alcohol, such as one or more components selected from the group consisting of nitrogen, helium, argon, and hydrogen.

[0060] Examples of the alcohol contained in the alcohol-containing fluid include one or more selected from the group consisting of methanol, ethanol, butanol, and isobutanol, and from the viewpoint of further increasing the p-xylene selectivity, methanol is preferred.

[0061] The alcohol-containing fluid to be brought into contact with the zeolite of the present embodiment may be one or more selected from the group consisting of a liquid, a gas, and a mixed fluid of a liquid and a gas. From the viewpoint of further increasing the p-xylene selectivity, however, a gas is preferable.

[0062] In the contact step, the zeolite of the present embodiment that has been activated may be used as the zeolite of the present embodiment that is brought into contact with the alcohol-containing fluid. A conventionally known activation treatment can be used for the activation treatment of the zeolite of the present embodiment, and the method is not limited to this. A specific example of the activation treatment is an activation treatment in which nitrogen gas is passed through the zeolite of the present embodiment under the following conditions: Flow rate of nitrogen gas: 5 mL / min to 100 mL / min Treatment temperature: 400°C to 600°C Treatment pressure: 0.05 MPa to 1 MPa (gauge pressure) Treatment time: 0.5 hours to 50 hours

[0063] The zeolite of the present embodiment in the contacting step may be formed into a predetermined shape. Examples of methods for forming the zeolite of the present embodiment include rolling granulation molding, press molding, extrusion molding, injection molding, slip casting, and sheet molding. Examples of the shape of the formed zeolite include spherical, approximately spherical, elliptical, disk-like, cylindrical, polyhedral, irregular, and petal-like. The zeolite of the present embodiment may be formed together with a binder to form a molded body containing the binder and the zeolite. The alcohol-containing fluid may be brought into contact with the zeolite of the present embodiment contained in the molded body by passing the alcohol-containing fluid through such a molded body. Examples of the binder include at least one selected from the group consisting of silica, alumina other than γ-alumina, kaolin, attapulgite, montmorillonite, bentonite, and sepiolite.

[0064] The zeolite of this embodiment is not particularly limited, but may be treated at a treatment temperature of 420° C., a treatment pressure (gauge pressure) of 0.2 MPa, a treatment time of 6 hours, and a methanol weight hourly space velocity of 1.0 Hr －１The p-xylene selectivity (hereinafter also referred to as "p-xylene selectivity (420°C)") when a treatment of contacting a mixed gas of nitrogen and methanol under the above conditions (hereinafter also referred to as "methanol contact treatment (420°C)") is performed is preferably 35% or more, more preferably 40% or more, and even more preferably 60% or more. The upper limit of the p-xylene selectivity (420°C) is not particularly limited, but examples include 100% or less or 99.9% or less. The upper and lower limits of the p-xylene selectivity (420°C) may be any combination of the above-mentioned upper and lower limits, but the p-xylene selectivity (420°C) is preferably 35% or more and 100% or less, more preferably 40% or more and 100% or less, even more preferably 40% or more and 99.9% or less, and particularly preferably 60% or more and 99.9% or less.

[0065] The p-xylene selectivity (420°C) can be determined by dividing the mass of p-xylene in the product produced by the methanol contact treatment (420°C) by the total mass of xylenes (p-xylene, o-xylene, and m-xylene) in the product, and expressing the result as a percentage. The zeolite of this embodiment to be subjected to the methanol contact treatment (420°C) may be a zeolite that has been activated by flowing nitrogen gas at 50 mL / min for 1 hour under conditions of a temperature of 450°C and a pressure of 0.2 MPa (gauge pressure).

[0066] The zeolite of this embodiment is not particularly limited, but the BTX yield when subjected to a methanol contact treatment (420°C) (hereinafter also referred to as "BTX yield (420°C)") is preferably 3% or more, more preferably 15% or more, and even more preferably 25% or more. The upper limit of the BTX yield (420°C) is not particularly limited, but examples include 100% or less or 70% or less. The upper and lower limit values ​​of the BTX yield (420°C) may be any combination of the above-mentioned upper and lower limit values, but are preferably 3% or more and 100% or less, more preferably 15% or more and 70% or less, and even more preferably 25% or more and 70% or less.

[0067] The BTX yield (420°C) can be determined by dividing the total mass of benzene, xylenes (p-xylene, o-xylene, and m-xylene), and toluene in the product produced by the methanol contact treatment (420°C) by the mass of the product (the total mass of all components in the product), and expressing this as a percentage.

[0068] The zeolite of this embodiment, which reforms alcohols into benzene, xylene, and toluene, can also be used to co-produce benzene, xylene, and toluene by reforming alcohols. The method for co-producing benzene, xylene, and toluene using the zeolite of this embodiment includes a step (contact step) of contacting the zeolite of this embodiment with an alcohol-containing fluid, similar to the method for producing xylene using the zeolite of this embodiment. The contact step in the method for co-producing benzene, xylene, and toluene is the same as the contact step in the method for producing xylene, and therefore a detailed description thereof will be omitted.

[0069] Next, a method for producing the zeolite of this embodiment will be described.

[0070] The method for producing a zeolite according to the present embodiment includes a step of incorporating a predetermined element into a 10-membered oxygen ring zeolite (hereinafter also referred to as a "predetermined element incorporating step").

[0071] In the predetermined element incorporation step, the method for incorporating the predetermined element into the 10-membered oxygen ring zeolite is not particularly limited, but it is preferable to use a contact treatment (hereinafter also referred to as a "predetermined element contact treatment") in which a solution containing the predetermined element (hereinafter also referred to as a "predetermined element solution") is brought into contact with the 10-membered oxygen ring zeolite.

[0072] When a predetermined element is contained in a 10-membered oxygen ring zeolite by a predetermined element contact treatment, the total pore volume of the 10-membered oxygen ring zeolite decreases depending on the treatment conditions. Therefore, when a predetermined element is contained in a 10-membered oxygen ring zeolite by a predetermined element contact treatment, the total pore volume of the 10-membered oxygen ring zeolite before contact with the predetermined element solution may be reduced to 0.21 cm or less depending on the treatment conditions. ３ / g, the total pore volume is 0.21 cm ３ / g or less, it is possible to obtain a zeolite (i.e., the zeolite of this embodiment). The reason why the total pore volume of the 10-membered oxygen ring zeolite is reduced by the contact treatment with a predetermined element is not clear, but it is presumed that when the contact treatment with a predetermined element is performed under predetermined conditions, the predetermined element becomes more likely to reach not only the surface (outer surface) of the 10-membered oxygen ring zeolite but also the interior thereof, thereby reducing the total pore volume.

[0073] In the predetermined element contact treatment, the oxygen 10-membered ring zeolite to be contacted with the predetermined element solution is a zeolite having a total pore volume of 0.35 cm3, since the zeolite of this embodiment is easily obtained. ３ / g or less, and ３ / g or less, and more preferably 0.21 cm ３ / g or less, and even more preferably 0.19 cm ３ The total pore volume of the 10-membered oxygen ring zeolite to be contacted with the predetermined element solution is particularly preferably 0 cm ３ / g, but is not particularly limited, for example, 0.05 cm ３ / g or more, 0.07cm ３ / g or more, or 0.15 cm ３ The upper and lower limits of the total pore volume of the 10-membered oxygen ring zeolite to be contacted with the predetermined element solution may be any combination of the upper and lower limits described above, but since the zeolite of this embodiment is easily obtained, it is preferable to use a value of 0.05 cm ３ / g or more 0.35cm ３ / g or less, and ３ / g or more 0.28cm ３ / g or less, and more preferably 0.07 cm ３ / g or more 0.28cm ３ / g or less, and even more preferably 0.15 cm ３ / g or more 0.28cm ３ It is particularly preferable that the SiO2 content is 1 / g or less.

[0074] As the 10-membered oxygen ring zeolite to be contacted with the predetermined element solution, it is preferable to use an oxygen 10-membered ring zeolite that has been subjected to the SDA removal treatment described below, and it is more preferable to use an oxygen 10-membered ring zeolite that is substantially free of SDA. The oxygen 10-membered ring zeolite that has been subjected to the SDA removal treatment is more likely to have a reduced total pore volume due to the predetermined element contact treatment than an oxygen 10-membered ring zeolite that has not been subjected to the SDA removal treatment. ３ / g or less (i.e., the zeolite of this embodiment) is easily obtained.

[0075] In the oxygen 10-membered ring zeolite to be contacted with the predetermined element solution, the framework structure, the type of T atoms constituting the framework structure, and SiO ２ / Al ２ O ３ The ratios are determined based on the framework structure of the zeolite of the present embodiment to be produced, the type of T atoms constituting the framework structure, and the SiO ２ / Al ２ O ３ It may be set appropriately depending on the ratio, and is not particularly limited.

[0076] The predetermined element solution to be contacted with the 10-membered oxygen ring zeolite is a solution containing the predetermined element and a solvent. The predetermined element contained in the predetermined element solution may be contained in the form of a compound containing the predetermined element. Examples of the compound containing the predetermined element include at least one compound selected from the group consisting of acetates, nitrates, ammonium salts, sulfates, hydroxides, and chlorides of the predetermined element. Among these, at least one of acetates, nitrates, and ammonium salts of the predetermined element is preferred. Specific examples of compounds containing the predetermined element include at least one compound selected from the group consisting of magnesium acetate, magnesium nitrate, magnesium chloride, magnesium sulfate, calcium nitrate, calcium chloride, calcium sulfate, phosphoric acid, ammonium hydrogen phosphate, diammonium hydrogen phosphate, titanium chloride, titanium sulfate, titanyl sulfate, boric acid, and ammonium tetraborate. At least one of magnesium acetate, calcium nitrate, and diammonium hydrogen phosphate is preferred. Examples of the solvent contained in the predetermined element solution include at least one of water and alcohol, with water being preferred.

[0077] The concentration of the predetermined element in the predetermined element solution and the amount of the predetermined element solution brought into contact with the 10-membered oxygen ring zeolite are determined so that the total pore volume of the 10-membered oxygen ring zeolite obtained by contacting the predetermined element solution is 0.21 cm ３ / g or less, and is not particularly limited, but the lower the concentration of the predetermined element in the predetermined element solution, the less likely it is that the total pore volume of the 10-membered oxygen ring zeolite subjected to the predetermined element contact treatment will decrease. For this reason, it is preferable that the total pore volume of the 10-membered oxygen ring zeolite before contact with the predetermined element solution is 0.21 cm ３ / g, it is preferable to appropriately adjust the concentration of the predetermined element in the predetermined element solution in consideration of the above-mentioned tendency, and it is more preferable to adjust the concentration so that the content of the predetermined element in the 10-membered oxygen ring zeolite brought into contact with the predetermined element solution is 3 mass% or more.

[0078] The contact conditions for the 10-membered oxygen ring zeolite and the predetermined element solution are as follows: the total pore volume of the 10-membered oxygen ring zeolite obtained by contacting with the predetermined element solution is 0.21 cm ３ / g or less, and is not particularly limited. For example, the contact time between the 10-membered oxygen ring zeolite and the predetermined element solution may be 0.1 minutes or more and 48 hours or less. For example, the contact temperature between the 10-membered oxygen ring zeolite and the predetermined element solution may be 5°C or more and 100°C or less. For example, the contact pressure between the 10-membered oxygen ring zeolite and the predetermined element solution may be 0 MPa or more and 1 MPa or less (gauge pressure).

[0079] By contacting the 10-membered oxygen ring zeolite with the predetermined element solution, the predetermined element is contained in the 10-membered oxygen ring zeolite. This allows the zeolite of the present embodiment to be produced. Note that the 10-membered oxygen ring zeolite that has been contacted with the predetermined element solution may be used as the zeolite of the present embodiment as is, or may be used as the zeolite of the present embodiment after being subjected to at least one of a drying treatment and a calcination treatment.

[0080] The drying treatment is a treatment for removing moisture from the 10-membered oxygen ring zeolite that has been brought into contact with a predetermined element solution. The drying conditions are not particularly limited as long as they can remove moisture from the 10-membered oxygen ring zeolite, but examples thereof include drying in an air atmosphere at 60°C to 180°C for 0.5 hours to 48 hours.

[0081] The calcination treatment is a treatment of calcining the 10-membered oxygen ring zeolite that has been brought into contact with a solution of a predetermined element or the dried 10-membered oxygen ring zeolite. Examples of the calcination conditions include the following: Calcination temperature: 350°C or higher, or 450°C or higher, and 700°C or lower, or 600°C or lower Calcination time: 0.5 hours or higher, or 1 hour or higher, and 24 hours or lower, or 12 hours or lower Calcination atmosphere: air atmosphere

[0082] As described above, the zeolite of the present embodiment may contain, in addition to the predetermined element, an element other than the predetermined element. The zeolite of the present embodiment that further contains the other element in addition to the predetermined element can be produced by a production method including the above-described predetermined element-incorporating step and a step of incorporating the other element into the 10-membered oxygen ring zeolite (hereinafter also referred to as the "other element-incorporating step").

[0083] In the other element inclusion step, the method for incorporating the other element into the 10-membered oxygen ring zeolite is not particularly limited, but for example, a contact treatment (hereinafter also referred to as "other element contact treatment") in which a solution containing the other element (hereinafter also referred to as "other element solution") is brought into contact with the 10-membered oxygen ring zeolite can be used.

[0084] The other-element solution used in the other-element contact treatment is a solution containing the other element and a solvent. The other element contained in the other-element solution may be contained in the form of a compound containing the other element. Examples of compounds containing the other element include at least one compound selected from the group consisting of nitrates, acetates, sulfates, and chlorides of the other element, with nitrates being preferred. Specific examples of compounds containing the other element include at least one compound selected from the group consisting of gallium nitrate, gallium chloride, zinc nitrate, zinc sulfate, zinc chloride, silver nitrate, iron (II) sulfate, iron (III) sulfate, iron chloride, iron oxalate, iron citrate, and iron nitrate, with at least one of gallium nitrate and zinc nitrate being preferred. Examples of solvents contained in the other-element solution include at least one of water and alcohol, with water being preferred.

[0085] The other element contact treatment is the same as the above-described predetermined element contact treatment except that a solution of another element is used instead of the predetermined element solution, and therefore a detailed description thereof will be omitted.

[0086] In the method for producing a zeolite of the present embodiment that further contains other elements, the order of the predetermined element-containing step and the other element-containing step is not particularly limited, and the predetermined element-containing step may be performed after the other element-containing step, or the other element-containing step may be performed after the predetermined element-containing step.

[0087] Here, when the contact treatment with the predetermined element is performed after the contact treatment with the other element, the total pore volume of the 10-membered oxygen ring zeolite is more likely to decrease than when the contact treatment with the predetermined element is performed after the contact treatment with the other element. Therefore, in the production method in which the contact treatment with the predetermined element is performed after the contact treatment with the other element, the total pore volume of the 10-membered oxygen ring zeolite before being subjected to these treatments is 0.21 cm ３ / g, the total pore volume is 0.21 cm ３ / g or less (i.e., the zeolite of the present embodiment) is more likely to be produced. For this reason, in the method for producing the zeolite of the present embodiment further containing other elements, it is preferable to carry out a step of containing the other element in the 10-membered oxygen ring zeolite by contact treatment with another element (other element inclusion step), followed by a step of containing the predetermined element in the 10-membered oxygen ring zeolite containing the other element by contact treatment with a predetermined element (predetermined element inclusion step).

[0088] The 10-membered oxygen ring zeolite used in the predetermined element-containing step and the other element-containing step may be a commercially available zeolite, or may be a zeolite obtained by crystallizing a composition containing an alumina source, a silica source, an organic structure-directing agent source, an alkali source, and water (hereinafter also referred to as a "raw material composition").

[0089] The method for producing the 10-membered oxygen ring zeolite by crystallizing the raw material composition will be described below.

[0090] The alumina source contained in the raw material composition is a compound containing aluminum (Al), and examples thereof include one or more selected from the group consisting of aluminum isopropoxide, aluminum sulfate, aluminum chloride, aluminum hydroxide, pseudoboehmite, alumina sol, and amorphous aluminosilicate, with amorphous aluminosilicate being preferred. Note that substances containing aluminum (Al) and silicon (Si), such as amorphous aluminosilicate, can be used not only as an alumina source but also as a silica source, which will be described later.

[0091] The silica source contained in the raw material composition is a compound containing silicon (Si), and examples thereof include one or more selected from the group consisting of silica sol, fumed silica, colloidal silica, precipitated silica, sodium silicate, amorphous silicic acid, and amorphous aluminosilicate, with amorphous aluminosilicate being preferred.

[0092] The organic structure-directing agent (hereinafter also referred to as "SDA") source may be any substance containing an SDA that directs a framework structure containing a 10-membered oxygen ring, and any known SDA known to direct 10-membered oxygen ring zeolite can be used. For example, an SDA that directs MFI zeolite can include at least one selected from the group consisting of normal butylamine, tetrapropylammonium bromide, diethylenetriamine, and cyclohexylamine. Among these, at least one selected from the group consisting of normal butylamine, diethylenetriamine, and cyclohexylamine is preferred, with normal butylamine being more preferred. Compared to other SDAs, normal butylamine, diethylenetriamine, and cyclohexylamine can further reduce the total pore volume of the produced 10-membered oxygen ring zeolite.

[0093] The SDA source may be a salt of SDA, such as one or more salts selected from chloride, bromide, iodide, and hydroxide.

[0094] The alkali source contained in the raw material composition is a compound containing an alkali metal element, and examples thereof include compounds containing one or more alkali metal elements selected from the group consisting of sodium, potassium, cesium, and rubidium. The alkali source may be in the form of one or more salts selected from the group consisting of hydroxides, carbonates, chlorides, bromides, iodides, and sulfates containing an alkali metal element. Preferred alkali sources include at least one selected from the group consisting of sodium hydroxide, sodium carbonate, sodium chloride, sodium bromide, sodium iodide, and sodium sulfate.

[0095] The water contained in the raw material composition may be, for example, distilled water, deionized water, pure water, or two or more of these. Note that when the raw materials other than water contained in the raw material composition contain water, such as hydrates, structural water, or solvents, the water contained in the raw materials other than water can be considered to be the water contained in the raw material composition.

[0096] The raw material composition may be composed only of an alumina source, a silica source, an SDA source, an alkali source, and water, but may also contain raw materials other than these raw materials.

[0097] The composition of the raw material composition can be appropriately selected depending on the skeletal structure of the 10-membered oxygen ring zeolite to be produced, and an example of a preferred composition is the following molar composition. Note that the ratios in the following compositions are molar (mol) ratios, and SiO ２ indicates the molar amount of silicon, and Al ２ O ３ indicates the molar amount of aluminum converted to alumina, and H ２ O represents the molar amount of water, M represents the molar amount of alkali metal elements (total molar amount of alkali metal elements), SDA represents the molar amount of organic structure directing agent, and OH － indicates the molar amount of hydroxide ions.

[0098] SiO ２ / Al ２ O ３ Ratio = 15 or more, preferably 23 or more, and 500 or less, preferably 300 or less SDA / SiO ２ Ratio M / SiO = 0.05 or more, preferably 0.10 or more, and 0.50 or less, preferably 0.30 or less ２ Ratio = 0.05 or more, preferably 0.10 or more, and 0.15 or less, preferably 0.20 or less ２ O / SiO ２ Ratio = 5 or more, preferably 10 or more, and 40 or less, preferably 20 or less OH － / SiO ２Ratio = 0.05 or more, preferably 0.10 or more, and 0.20 or less, preferably 0.15 or less

[0099] The raw material composition can be obtained by mixing the above-mentioned alumina source, silica source, SDA source, alkali source, water, and other raw materials that may be contained as needed.

[0100] The crystallization treatment of the raw material composition is not particularly limited as long as it can crystallize the raw material composition so as to obtain a 10-membered oxygen ring zeolite. A preferred crystallization treatment method is to subject the raw material composition to hydrothermal treatment. For example, the hydrothermal treatment may be carried out by placing the raw material composition in a sealed pressure-resistant container and heating it. Examples of hydrothermal treatment conditions include the following: Treatment temperature: 90°C or higher, or 115°C or higher, and 200°C or lower, or 180°C or lower Treatment time: 10 hours or higher, or 20 hours or higher, and 72 hours or lower, or 48 hours or lower Treatment pressure: autogenous pressure

[0101] The crystallization treatment of the raw material composition may be carried out after adding seed crystals to the raw material composition. The seed crystals are zeolite that has the function of promoting the formation of the framework structure of the 10-membered oxygen ring zeolite to be produced. For example, a zeolite having the same framework structure as the zeolite to be produced can be used. The amount of seed crystals added can be, for example, 0.1% by mass or more and 10% by mass or less, or 0.5% by mass or more and 3% by mass or less, relative to 100% by mass of the raw material composition (excluding the seed crystals).

[0102] The 10-membered oxygen ring zeolite obtained by the above-mentioned crystallization treatment may be subjected to one or more treatments selected from the group consisting of a washing treatment, a drying treatment, an SDA removal treatment, and an ammonium treatment, and is preferably subjected to at least an SDA removal treatment. The 10-membered oxygen ring zeolite that has been subjected to the SDA removal treatment is likely to have a reduced total pore volume due to the predetermined element contact treatment, and the total pore volume is likely to be reduced to 0.21 cm or less after the predetermined element inclusion step. ３ / g or less, the zeolite of this embodiment is easily produced.

[0103] The washing treatment is a step of washing the 10-membered oxygen ring zeolite. For example, in the washing treatment, the 10-membered oxygen ring zeolite may be washed with pure water.

[0104] The drying treatment is a treatment for removing moisture from the 10-membered oxygen ring zeolite. The conditions for the drying treatment are not particularly limited as long as moisture can be removed from the 10-membered oxygen ring zeolite. For example, the drying temperature may be 100°C or higher and 150°C or lower. For example, the drying time may be 2 hours or higher and 20 hours or lower. For example, the drying atmosphere may be in the air.

[0105] The SDA removal treatment is a treatment for removing SDA contained in the 10-membered oxygen ring zeolite. Usually, zeolite crystallized using SDA contains SDA in its pores. By including the SDA removal step, it is possible to remove the SDA contained in the 10-membered oxygen ring zeolite.

[0106] The SDA removal treatment can be performed by any method as long as it removes the SDA. Examples of methods for removing the SDA include at least one selected from the group consisting of a liquid-phase treatment using an acidic aqueous solution, an exchange treatment using a resin, and a heat treatment (thermal decomposition). From the viewpoint of production efficiency, the SDA removal treatment is preferably a heat treatment (thermal decomposition). The conditions for the heat treatment (thermal decomposition) are not particularly limited as long as the SDA is removed. For example, the heat treatment temperature may be 400°C or higher and 800°C or lower. Furthermore, for example, the heat treatment time may be 1 hour or higher and 5 hours or lower. Furthermore, for example, the heat treatment may be performed in air.

[0107] The ammonium treatment is a treatment for removing alkali metals contained in the 10-membered oxygen ring zeolite. The ammonium treatment can be carried out by a known method, for example, by contacting the 10-membered oxygen ring zeolite with an aqueous solution containing ammonium ions. By the ammonium treatment, the cation type of the 10-membered oxygen ring zeolite becomes NH ４The ammonium-treated 10-membered oxygen ring zeolite can be converted from the cation type to the proton type (H ＋ It can also be made into a type.

[0108] The zeolite of this embodiment described above can increase the p-xylene selectivity in the production of xylene by alcohol reforming. The reason why the zeolite of this embodiment increases the p-xylene selectivity is not clear, but it is thought that the total pore volume of the 10-membered oxygen ring zeolite is 0.21 cm ３ / g or less, and the inclusion of a predetermined element in the 10-membered oxygen ring zeolite is thought to cause steric hindrance when xylenes generated inside the 10-membered oxygen ring zeolite (at acid sites inside the zeolite) are discharged through the pores. As a result, it is presumed that o-xylene and m-xylene, among the xylenes generated inside the 10-membered oxygen ring zeolite, are less likely to be discharged from the pores, and only p-xylene, among the xylenes generated inside the pores, is more likely to be discharged outside the pores, thereby increasing the p-xylene selectivity.

[0109] Furthermore, according to the zeolite of the present embodiment, the p-xylene selectivity can be increased without using an expensive organosilicon such as that used in Patent Document 1. Therefore, the zeolite of the present embodiment does not necessarily require equipment for detoxifying waste liquid containing organosilicon, and can be applied to industrial processes at low cost.

[0110] The present disclosure will be explained in more detail below by way of examples, but the present disclosure is not limited to the following examples in any way.

[0111] (Identification of crystalline phase) The measurement sample (zeolite) was subjected to XRD measurement using a general powder X-ray diffractometer (device name: Ultima IV, manufactured by Rigaku Corporation). The measurement conditions were as follows: Acceleration current / voltage: 10 mA / 30 kV Radiation source: CuKα radiation (λ=1.54178 Å) Measurement mode: Continuous scan Scan condition: 2° / min Measurement range: 2θ=10 to 70° Scattering slit: 1 / 3° Divergence slit: 1 / 3° Receiving slit: 0.3 mm Filter: Ni filter

[0112] The obtained XRD pattern was subjected to baseline correction and detection and intensity analysis of each corrected XRD peak using an analysis program attached to the measurement device (product name: IGOR Pro 8, manufactured by WaveMetrics). The crystalline phase of the zeolite was identified by comparing the corrected XRD pattern with a reference pattern.

[0113] (Composition Analysis) As a pretreatment, the measurement sample was heat-treated in an air atmosphere at 600°C for 60 minutes. The pretreated measurement sample was dissolved in a mixed aqueous solution of hydrofluoric acid and nitric acid to prepare a sample solution. The sample solution was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) using a general ICP device (device name: OPTIMA5300DV, manufactured by PerkinElmer). From the obtained measured values ​​of aluminum (Al), silicon (Si), predetermined elements, and other elements, the SiO of the measurement sample was determined. ２ / Al ２ O ３ The mass ratio of the predetermined element to the measurement sample (predetermined element content), and the mass ratio of other elements to the measurement sample (other element content) were calculated. Note that the mass of the measurement sample was the mass of the pretreated measurement sample.

[0114] (Total pore volume) A common nitrogen adsorption apparatus (apparatus name: BELSORP-mini II, manufactured by Microtrac-Bell) was used to obtain the nitrogen adsorption and desorption isotherm for the measurement sample. The nitrogen gas adsorption was performed using a constant volume method. The measurement conditions are as follows: Measurement temperature: -196°C Pretreatment: 350°C, vacuum drying for 2 hours

[0115] p / p from nitrogen adsorption / desorption isotherm ０ The adsorption amount of nitrogen gas V (cm ３ ) was determined, and the total pore volume was calculated by substituting the obtained adsorption amount V into the above formula (1).

[0116] (IR Spectrum) The IR spectrum was measured using an FT-IR device (device name: FT / IR-6600, manufactured by JASCO Corporation) equipped with a heated transmission cell (manufactured by Makuhari Rikagaku Glass Manufacturing Co., Ltd.). The measurement sample was a disk (approximately 10 mg / cm ２ ) and pretreated in a thermal transmission cell at 450°C for 2 hours under vacuum. The temperature was then lowered to 200°C under vacuum conditions, and the background spectrum was measured under the following measurement conditions. Measurement method: thermal transmission method Measurement temperature: 200°C Measurement wavelength range: 800 to 4000 cm-1 Resolution: 2 cm-1 Number of accumulations: 128 Measurement atmosphere: vacuum

[0117] Subsequently, 2,6-di-tert-butylpyridine was introduced into the heating permeation cell and brought into contact with the measurement sample at 200°C for 30 minutes at 100 Pa. Thereafter, the heating permeation cell was treated under vacuum at 200°C for 30 minutes to remove excess 2,6-di-tert-butylpyridine, and then the adsorption spectrum was measured under the above-mentioned measurement conditions. The background spectrum was subtracted from the obtained adsorption spectrum to obtain a difference spectrum. In the obtained difference spectrum, p (1600 cm －１ ~1620cm －１ ) maximum intensity (height intensity) and p (1630 cm －１ ~1650cm －１ The maximum intensity (height intensity) of each of the samples was measured, and the IR peak ratio was calculated.

[0118] Synthesis Example 1 (Synthesis of MFI zeolite) n-butylamine (hereinafter also referred to as "NBA"), a 48 mass% aqueous solution of sodium hydroxide, pure water, and amorphous aluminosilicate (SiO ２ / Al ２ O ３ The raw material composition having the following molar composition was obtained by mixing the above materials: SiO ２ / Al ２ O ３ Ratio = 50 NBA / SiO ２ Ratio = 0.10 Na / SiO ２ Ratio = 0.10OH － / SiO ２ Ratio = 0.10H ２ O / SiO ２ ratio = 11

[0119] The seed crystals (MFI type zeolite; SiO ) were added to the raw material composition so that the seed crystal content was 1% by mass relative to 100% by mass of the raw material composition. ２ / Al ２ O ３ The raw material composition (molar ratio: 2400) was mixed with 55 g of the raw material composition, and then the mixture was filled into an 80 mL sealed container. After filling, the container was rotated at 55 rpm while undergoing a hydrothermal reaction at 150°C for 36 hours under autogenous pressure to obtain a crystallized product. The obtained crystallized product was subjected to solid-liquid separation, washed with pure water, and dried in an air atmosphere at 110°C, and then recovered. The crystallized product (hereinafter also referred to as "crystallized product of Synthesis Example 1") consisted of a single phase of MFI zeolite, and SiO ２ / Al ２ O ３ The molar ratio is 48 and the total pore volume is 0.23 cm ３ / g.

[0120] Next, the obtained crystallized product (MFI zeolite) of Synthesis Example 1 was calcined in an air atmosphere at 600°C for 2 hours (to perform SDA removal treatment). ４ The cation type was NH ４The MFI zeolite was washed with pure water and dried in an air atmosphere at 110°C for 12 hours, thereby obtaining the MFI zeolite of this synthesis example.

[0121] The MFI zeolite of this synthesis example is SiO ２ / Al ２ O ３ The molar ratio is 48 and the total pore volume is 0.25 cm ３ The MFI zeolite of this synthesis example had an IR peak ratio of 0.1.

[0122] Synthesis Example 2 A raw material composition having the following molar composition was obtained in the same manner as in Synthesis Example 1, except that tetrapropylammonium bromide (hereinafter also referred to as "TPABr") was used instead of NBA and the molar composition was as follows: SiO ２ / Al ２ O ３ Ratio = 50 TPABr / SiO ２ Ratio = 0.05 Na / SiO ２ Ratio = 0.17 OH － / SiO ２ Ratio = 0.17H ２ O / SiO ２ ratio = 10

[0123] The seed crystals (MFI type zeolite; SiO ) were added to the raw material composition so that the seed crystal content was 1% by mass relative to 100% by mass of the raw material composition. ２ / Al ２ O ３ The raw material composition (molar ratio: 50) was mixed with 55 g of the raw material composition, and then the mixture was filled into an 80 mL sealed container. After filling, the container was rotated at 55 rpm while undergoing a hydrothermal reaction at 115°C for 84 hours under autogenous pressure to obtain a crystallized product. The obtained crystallized product was subjected to solid-liquid separation, washed with pure water, and dried in an air atmosphere at 110°C, and then recovered. The crystallized product (hereinafter also referred to as "crystallized product of Synthesis Example 2") consisted of a single phase of MFI zeolite, and SiO ２ / Al ２ O ３ The zeolite was an MFI type zeolite (crystalline aluminosilicate) with a ratio of 48.

[0124] Next, the obtained crystallized product of Synthesis Example 2 (MFI zeolite) was subjected to calcination, ion exchange, washing, and drying under the same conditions as those for calcination, ion exchange, washing, and drying that were performed on the crystallized product of Synthesis Example 1, thereby obtaining MFI zeolite of this Synthesis Example.

[0125] The MFI zeolite of this synthesis example is SiO ２ / Al ２ O ３ The molar ratio is 48 and the total pore volume is 0.64 cm ３ The MFI zeolite of this synthesis example had an IR peak ratio of 0.0.

[0126] Synthesis Example 3 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ Amorphous aluminosilicate (SiO ２ / Al ２ O ３ A raw material composition having the following molar composition was obtained in the same manner as in Synthesis Example 1, except that SiO 2 (ratio: 83) was used and the molar composition was as follows: ２ / Al ２ O ３ Ratio = 83 NBA / SiO ２ Ratio = 0.10 Na / SiO ２ Ratio = 0.10OH － / SiO ２ Ratio = 0.10H ２ O / SiO ２ ratio = 11

[0127] The seed crystals (MFI type zeolite; SiO ) were added to the raw material composition so that the seed crystal content was 1% by mass relative to 100% by mass of the raw material composition. ２ / Al ２ O ３The raw material composition (molar ratio: 2400) was mixed with 55 g of the raw material composition, and then the mixture was filled into an 80 mL sealed container. After filling, the container was rotated at 55 rpm while undergoing a hydrothermal reaction at 150°C for 36 hours under autogenous pressure to obtain a crystallized product. The obtained crystallized product was subjected to solid-liquid separation, washed with pure water, and dried in an air atmosphere at 110°C, and then recovered. The crystallized product (hereinafter also referred to as "crystallized product of Synthesis Example 3") consisted of a single phase of MFI zeolite, and SiO ２ / Al ２ O ３ It was an MFI type zeolite (crystalline aluminosilicate) with a molar ratio of 80.

[0128] Next, the obtained crystallized product of Synthesis Example 3 (MFI zeolite) was subjected to calcination, ion exchange, washing, and drying under the same conditions as those for calcination, ion exchange, washing, and drying that were performed on the crystallized product of Synthesis Example 1, thereby obtaining MFI zeolite of this Synthesis Example.

[0129] The MFI zeolite of this synthesis example is SiO ２ / Al ２ O ３ The molar ratio is 80 and the total pore volume is 0.21 cm ３ The MFI zeolite of this synthesis example had an IR peak ratio of 0.1.

[0130] Synthesis Example 4 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ Amorphous aluminosilicate (SiO ２ / Al ２ O ３ A raw material composition having the following molar composition was obtained in the same manner as in Synthesis Example 1, except that SiO 2 (ratio: 216) was used and the molar composition was as follows: ２ / Al ２ O ３ Ratio = 216 NBA / SiO ２ Ratio = 0.10 Na / SiO ２ Ratio = 0.10OH － / SiO ２ Ratio = 0.10H２ O / SiO ２ ratio = 11

[0131] The seed crystals (MFI type zeolite; SiO ) were added to the raw material composition so that the seed crystal content was 1% by mass relative to 100% by mass of the raw material composition. ２ / Al ２ O ３ The raw material composition (molar ratio: 2400) was mixed with 55 g of the raw material composition, and then the mixture was filled into an 80 mL sealed container. After filling, the container was rotated at 55 rpm while undergoing a hydrothermal reaction at 150°C for 36 hours under autogenous pressure to obtain a crystallized product. The obtained crystallized product was subjected to solid-liquid separation, washed with pure water, and dried in an air atmosphere at 110°C, and then recovered. The crystallized product (hereinafter also referred to as "crystallized product of Synthesis Example 4") consisted of a single phase of MFI zeolite, and SiO ２ / Al ２ O ３ It was an MFI type zeolite (crystalline aluminosilicate) with a molar ratio of 197.

[0132] Next, the obtained crystallized product of Synthesis Example 3 (MFI zeolite) was subjected to calcination, ion exchange, washing, and drying under the same conditions as those for calcination, ion exchange, washing, and drying that were performed on the crystallized product of Synthesis Example 1, thereby obtaining MFI zeolite of this Synthesis Example.

[0133] The MFI zeolite of this synthesis example is SiO ２ / Al ２ O ３ The molar ratio is 206 and the total pore volume is 0.21 cm ３ The MFI zeolite of this synthesis example had an IR peak ratio of 0.1.

[0134] Example 1 An aqueous magnesium acetate solution was obtained by dissolving 5.29 g of magnesium acetate tetrahydrate in 4 g of pure water at 60° C. 10.0 g of the MFI zeolite of Synthesis Example 1 and the aqueous magnesium acetate solution were mixed in a mortar for 10 minutes at room temperature and atmospheric pressure, and the resulting mixture was dried overnight in an air atmosphere at 110° C. and then calcined in an air atmosphere at 550° C. for 2 hours to obtain an MFI zeolite of this example on which magnesium was supported (hereinafter also referred to as "magnesium-containing MFI zeolite").

[0135] The magnesium-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium-containing MFI zeolite of this example was an aluminosilicate having a magnesium content of 6.0% by mass (hereinafter also referred to as "Mg content") relative to the MFI zeolite of this example, and a magnesium ratio of 48. The magnesium-containing MFI zeolite of this example had a total pore volume of 0.18 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.8.

[0136] Comparative Example 1 The MFI zeolite obtained in Synthesis Example 1 was used as the MFI zeolite of this comparative example.

[0137] Comparative Example 2 A zinc nitrate aqueous solution was obtained by dissolving 0.49 g of zinc nitrate hexahydrate in 3.8 g of pure water. A zinc-supported MFI zeolite of this comparative example (hereinafter also referred to as "zinc-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the zinc nitrate aqueous solution was used instead of the magnesium acetate aqueous solution.

[0138] The zinc-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The zinc-containing MFI zeolite of this comparative example was an aluminosilicate having a zinc content of 1.1% by mass, a zinc content ratio of 48, and a zinc content of 1.1% by mass relative to the MFI zeolite of this comparative example (hereinafter also referred to as the "Zn content"). ３ / g, and the IR peak ratio in the difference spectrum was 0.0.

[0139] Example 2 An MFI zeolite of this example supporting magnesium and zinc (hereinafter also referred to as "magnesium / zinc-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the zinc-containing MFI zeolite obtained in Comparative Example 2 was used instead of the MFI zeolite of Synthesis Example 1.

[0140] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 48, a Mg content of 6.0 mass%, and a Zn content of 1.1 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.19 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.7.

[0141] Example 3 An aqueous calcium nitrate solution was obtained by dissolving 3.54 g of calcium nitrate tetrahydrate in 3 g of pure water. An MFI zeolite of this example supporting calcium and zinc (hereinafter also referred to as "calcium / zinc-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the zinc-containing MFI zeolite obtained in Comparative Example 2 was used instead of the MFI zeolite of Synthesis Example 1 and that a calcium nitrate aqueous solution was used instead of the magnesium acetate aqueous solution.

[0142] The calcium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The calcium / zinc-containing MFI zeolite of this example was an aluminosilicate having a calcium / zinc ratio of 48, a calcium mass ratio (hereinafter also referred to as "Ca content") relative to the MFI zeolite of this example of 6.0 mass%, and a Zn content of 1.1 mass%. The calcium / zinc-containing MFI zeolite of this example had a total pore volume of 0.20 cm ３ / g, and the IR peak ratio in the difference spectrum was 3.6.

[0143] Example 4 An aqueous solution of diammonium hydrogen phosphate was obtained by dissolving 2.56 g of diammonium hydrogen phosphate in 4 g of pure water. An MFI zeolite of this example supporting phosphorus and zinc (hereinafter also referred to as "phosphorus / zinc-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the zinc-containing MFI zeolite obtained in Comparative Example 2 was used instead of the MFI zeolite of Synthesis Example 1 and that an aqueous solution of diammonium hydrogen phosphate was used instead of the aqueous magnesium acetate solution.

[0144] The phosphorus / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３The phosphorus / zinc-containing MFI zeolite of this example was an aluminosilicate having a total pore volume of 0.14 cm3, a mass ratio of phosphorus element (hereinafter also referred to as "P content") relative to the MFI zeolite of this example of 6.0 mass%, and a Zn content of 1.1 mass%. ３ / g.

[0145] Example 5 A zinc nitrate aqueous solution was obtained by dissolving 0.88 g of gallium nitrate n-hydrate (gallium nitrate content: 64.5% by mass) in 2.3 g of pure water. A gallium-supported MFI zeolite of this example (hereinafter also referred to as "gallium-containing MFI zeolite") was obtained in the same manner as in Comparative Example 2, except that the gallium nitrate aqueous solution was used instead of the zinc nitrate aqueous solution.

[0146] An MFI zeolite of this example supporting magnesium and gallium (hereinafter also referred to as "magnesium / gallium-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the obtained gallium-containing MFI zeolite was used instead of the MFI zeolite of Synthesis Example 1.

[0147] The magnesium / gallium-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / gallium-containing MFI zeolite of this example was an aluminosilicate having a gallium content of 1.7% by mass (hereinafter also referred to as "Ga content"), a gallium content of 48, a magnesium content of 6.0% by mass, and a gallium content of 1.7% by mass relative to the MFI zeolite of this example. ３ / g, and the IR peak ratio in the difference spectrum was 2.0.

[0148] Example 6 A zinc-containing MFI zeolite was obtained in the same manner as in Comparative Example 2, except that the MFI zeolite of Synthesis Example 3 was used instead of the MFI zeolite of Synthesis Example 1, and the amount of zinc nitrate hexahydrate added was changed from 0.49 g to 0.28 g. A magnesium / zinc-containing MFI zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 1, except that the obtained zinc-containing MFI zeolite was used instead of the MFI zeolite of Synthesis Example 1, and the amount of magnesium acetate tetrahydrate added was changed from 5.29 g to 3.53 g.

[0149] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 80, a Mg content of 4.0 mass%, and a Zn content of 0.66 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.17 cm ３ / g, and the IR peak ratio in the difference spectrum was 3.5.

[0150] Example 7 A magnesium / zinc-containing MFI zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 6, except that the amount of magnesium acetate tetrahydrate added was changed from 3.53 g to 5.29 g.

[0151] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 80, a Mg content of 6.0 mass%, and a Zn content of 0.66 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.15 cm ３ / g, and the IR peak ratio in the difference spectrum was 2.2.

[0152] Example 8 A magnesium / zinc-containing MFI zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 6, except that the amount of magnesium acetate tetrahydrate added was changed from 3.53 g to 5.29 g and the amount of zinc nitrate hexahydrate added was changed from 0.28 g to 0.34 g.

[0153] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 80, a Mg content of 6.0 mass%, and a Zn content of 0.79 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.13 cm ３ / g, and the IR peak ratio in the difference spectrum was 2.1.

[0154] Example 9 A magnesium / zinc-containing MFI zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 6, except that the amount of magnesium acetate tetrahydrate added was changed from 3.53 g to 5.29 g and the amount of zinc nitrate hexahydrate added was changed from 0.28 g to 0.87 g.

[0155] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 80, a Mg content of 6.0 mass%, and a Zn content of 2.0 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.11 cm ３ / g, and the IR peak ratio in the difference spectrum was 4.0.

[0156] Example 10 A zinc-containing MFI zeolite was obtained in the same manner as in Comparative Example 2, except that the MFI zeolite of Synthesis Example 4 was used instead of the MFI zeolite of Synthesis Example 1, and the amount of zinc nitrate hexahydrate added was changed from 0.49 g to 0.28 g. A magnesium / zinc-containing MFI zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 1, except that the obtained zinc-containing MFI zeolite was used instead of the MFI zeolite of Synthesis Example 1, and the amount of magnesium acetate tetrahydrate added was changed from 5.29 g to 3.53 g.

[0157] The magnesium / zinc-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this example was an aluminosilicate having a pore ratio of 206, a Mg content of 4.0 mass%, and a Zn content of 0.66 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this example was 0.17 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.7.

[0158] Example 11 Instead of the MFI zeolite in Synthesis Example 1, commercially available MEL zeolite (ZSM-11, manufactured by ACS Material, SiO ２ / Al ２ O ３ A zinc-containing MFI zeolite was obtained in the same manner as in Comparative Example 2, except that the obtained zinc-containing MFI zeolite was used instead of the MFI zeolite of Synthesis Example 1, and a magnesium / zinc-containing MEL zeolite of this example supporting magnesium and zinc was obtained in the same manner as in Example 1.

[0159] The magnesium / zinc-containing MEL-type zeolite of this example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MEL-type zeolite of this example was an aluminosilicate having a pore ratio of 50, a Mg content of 6.0 mass%, and a Zn content of 1.1 mass%. The total pore volume of the magnesium / zinc-containing MEL-type zeolite of this example was 0.17 cm ３ / g, and the IR peak ratio in the difference spectrum was 3.2.

[0160] Example 12 A calcium nitrate aqueous solution was obtained by dissolving 3.54 g of calcium nitrate tetrahydrate in 3 g of pure water. A calcium-supported MFI zeolite of this example (hereinafter also referred to as "calcium-containing MFI zeolite") was obtained in the same manner as in Example 1, except that a calcium nitrate aqueous solution was used instead of a magnesium acetate aqueous solution.

[0161] The calcium-containing MFI zeolite of this example is SiO ２ / Al ２ O ３ The calcium-containing MFI zeolite of this example was an aluminosilicate having a Ca content of 6.0 mass% and a pore ratio of 48. The total pore volume of the calcium-containing MFI zeolite of this example was 0.21 cm ３ / g, and the IR peak ratio in the difference spectrum was 5.0.

[0162] Comparative Example 3 A magnesium-supported MFI zeolite of this comparative example (magnesium-containing MFI zeolite) was obtained in the same manner as in Example 1, except that the crystallized product of Synthesis Example 1 was used instead of the MFI zeolite of Synthesis Example 1.

[0163] The magnesium-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The magnesium-containing MFI zeolite of this comparative example was an aluminosilicate having a pore ratio of 48 and a Mg content of 6.0 mass%. The total pore volume of the magnesium-containing MFI zeolite of this comparative example was 0.23 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.4.

[0164] Comparative Example 4 A magnesium-supported MFI zeolite of this comparative example (magnesium-containing MFI zeolite) was obtained in the same manner as in Example 1, except that the MFI zeolite of Synthesis Example 2 was used instead of the MFI zeolite of Synthesis Example 1.

[0165] The magnesium-containing MFI zeolite of this comparative example is SiO ２ / Al ２O ３ The magnesium-containing MFI zeolite of this comparative example was an aluminosilicate having a pore ratio of 48 and a Mg content of 6.0 mass%. The total pore volume of the magnesium-containing MFI zeolite of this comparative example was 0.62 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.5.

[0166] Comparative Example 5 A magnesium-containing MFI zeolite of this comparative example was prepared in the same manner as in Comparative Example 4, except that the amount of magnesium acetate tetrahydrate added was changed from 5.29 g to 10.59 g.

[0167] The magnesium-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The magnesium-containing MFI zeolite of this comparative example was an aluminosilicate having a pore ratio of 48 and a Mg content of 12.0 mass%. The total pore volume of the magnesium-containing MFI zeolite of this comparative example was 0.52 cm ３ / g.

[0168] Comparative Example 6 A gallium-containing MFI zeolite of this comparative example was obtained in the same manner as in Example 5. That is, a zinc nitrate aqueous solution was obtained by dissolving 0.88 g of gallium nitrate n-hydrate (gallium nitrate content: 64.5% by mass) in 2.3 g of pure water. A gallium-containing MFI zeolite of this comparative example was obtained in the same manner as in Comparative Example 2, except that the gallium nitrate aqueous solution was used instead of the zinc nitrate aqueous solution.

[0169] The gallium-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The gallium-containing MFI zeolite of this comparative example was an aluminosilicate having a Ga content of 1.7 mass% and a pore volume of 0.24 cm. ３ / g.

[0170] Comparative Example 7 A magnesium / zinc-containing MFI zeolite of this comparative example was prepared in the same manner as in Example 6, except that the amount of magnesium acetate tetrahydrate added was changed from 3.53 g to 1.76 g.

[0171] The magnesium / zinc-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this comparative example was an aluminosilicate having a pore ratio of 80, a Mg content of 2.0 mass%, and a Zn content of 0.66 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this comparative example was 0.22 cm ３ / g.

[0172] Comparative Example 8 A zinc-containing MFI zeolite was obtained in the same manner as in Comparative Example 2, except that the amount of zinc nitrate hexahydrate added was changed from 0.49 g to 0.28 g. The magnesium / zinc-containing MFI zeolite of this comparative example was prepared in the same manner as in Example 1, except that the obtained zinc-containing MFI zeolite was used instead of the MFI zeolite of Synthesis Example 1 and the amount of magnesium acetate tetrahydrate added was changed from 5.29 g to 3.53 g.

[0173] The magnesium / zinc-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The magnesium / zinc-containing MFI zeolite of this comparative example was an aluminosilicate having a pore ratio of 48, a Mg content of 4.0 mass%, and a Zn content of 0.66 mass%. The total pore volume of the magnesium / zinc-containing MFI zeolite of this comparative example was 0.24 cm ３ / g, and the IR peak ratio in the difference spectrum was 1.2.

[0174] Comparative Example 9 A zinc nitrate aqueous solution was obtained by dissolving 0.49 g of zinc nitrate hexahydrate in 3.8 g of pure water. An MFI zeolite of this comparative example supporting zinc and magnesium (hereinafter also referred to as "zinc / magnesium-containing MFI zeolite") was obtained in the same manner as in Example 1, except that the magnesium-containing MFI zeolite of Example 1 was used instead of the MFI zeolite of Synthesis Example 1 and the zinc nitrate aqueous solution was used instead of the magnesium acetate aqueous solution.

[0175] The zinc / magnesium-containing MFI zeolite of this comparative example is SiO ２ / Al ２ O ３The zinc / magnesium-containing MFI zeolite of this comparative example was an aluminosilicate having a Zn content of 1.1 mass% and a Mg content of 6.0 mass%. The total pore volume of the zinc / magnesium-containing MFI zeolite of this comparative example was 0.22 cm ３ / g.

[0176] Comparative Example 10 A nickel nitrate aqueous solution was obtained by dissolving 0.43 g of nickel(II) nitrate hexahydrate in 2 g of pure water. A nickel-supported MFI zeolite of this comparative example (hereinafter also referred to as "nickel-containing MFI zeolite") was obtained in the same manner as in Example 1, except that a nickel nitrate aqueous solution was used instead of the magnesium acetate aqueous solution.

[0177] The nickel-containing MFI zeolite of this comparative example was SiO ２ / Al ２ O ３ The nickel content of the MFI zeolite of this comparative example was 1.0 mass%. ... ３ / g.

[0178] Comparative Example 11 No. 3 aqueous sodium silicate solution (SiO ２ 14.5 mass% converted to Si, Na ２ 7.06 g of silica-supported MFI zeolite (containing 4.5% by mass of Na, calculated as O) and 10.0 g of the MFI zeolite of Synthesis Example 1 were mixed in a mortar for 10 minutes, and the resulting mixture was dried overnight at 110°C in an air atmosphere and then calcined at 550°C in an air atmosphere for 2 hours, thereby obtaining an MFI zeolite of this comparative example on which silica was supported (hereinafter also referred to as "silica-supported MFI zeolite").

[0179] The silica-supported MFI zeolite of this comparative example is SiO ２ / Al ２ O ３ The silica-supported MFI zeolite of this comparative example had a total pore volume of 0.13 cm3, and the mass ratio of the supported silicon element to the MFI zeolite of this comparative example (hereinafter also referred to as the "Si content") was 8.4 mass%.３ / g, and the IR peak ratio in the difference spectrum was 0.0.

[0180] The properties of the zeolites of each Example and Comparative Example are shown in Tables 1 and 2. In Tables 1 and 2, SAR is the ratio of SiO ２ / Al ２ O ３ Refers to the ratio.

[0181] As can be seen from the results of Comparative Examples 1, 2, and 6 shown in the table above, simply supporting other elements such as zinc or gallium on the 10-membered oxygen ring zeolite did not significantly change the total pore volume. On the other hand, as is clear from a comparison of Comparative Example 2 with Examples 2, 3, and 4, and a comparison of Comparative Example 6 with Example 5, supporting a specific element such as magnesium, calcium, or phosphorus on the 10-membered oxygen ring zeolite reduced the total pore volume. From these results, it was inferred that in the 10-membered oxygen ring zeolites of Examples 1 to 12, at least a portion of the specific element such as magnesium, calcium, or phosphorus was supported on the inner surfaces of the zeolite pores, resulting in a reduction in the total pore volume. On the other hand, in Comparative Example 3, in which magnesium was supported on a 10-membered oxygen ring zeolite that had not been subjected to a calcination treatment (a zeolite that had not been subjected to an SDA removal treatment), and in Comparative Example 7, which had a lower Mg content than the other Examples and Comparative Examples, the total pore volume was less likely to decrease, demonstrating that magnesium was less likely to be supported on the inner surfaces of the pores.

[0182] Furthermore, as can be seen from the IR peak ratios of Example 1 and Comparative Example 1 shown in the table above, the IR peak ratio increased by supporting magnesium on MFI zeolite. Furthermore, as can be seen from the IR peak ratios of Examples 2 to 4 and Comparative Example 2 shown in Table 1 above, the IR peak ratio increased by supporting a predetermined element such as calcium, magnesium, or phosphorus on zinc-containing MFI zeolite. These results demonstrate that predetermined elements such as magnesium, calcium, or phosphorus are easily supported on the outer surface of zeolite. On the other hand, as can be seen from the IR peak ratios of Comparative Example 1 and Comparative Example 2, the IR peak ratio hardly changed even when zinc was supported on MFI zeolite. From these results, it was inferred that in the MFI zeolite of Comparative Example 2, zinc was supported on a site other than the outer surface of the MFI zeolite (for example, the interior of the MFI zeolite).

[0183] Measurement Example 1 <Methanol Reforming Reaction> Using a fixed-bed flow reactor, 2 g of a measurement sample was packed into a stainless steel reaction tube with an inner diameter of 8 mm. Nitrogen was passed through the reaction tube at a flow rate of 50 mL / min, a temperature of 450°C, and 0.2 MPa (gauge pressure) for 1 hour, which was used as a pretreatment (activation treatment). After the pretreatment, nitrogen supplied at a flow rate of 20 mL / min and gaseous methanol obtained by vaporizing liquid methanol supplied at 2 g / min at 65°C were supplied to the reaction tube, and the reaction was continued at 420°C, 0.2 MPa (gauge pressure), and a weight hourly space velocity of methanol of 1.0 hr. －１ A mixed gas of nitrogen and methanol (nitrogen / methanol mixed gas) was passed through the reaction tube so that the concentration of methanol at the inlet and outlet of the fixed-bed flow-type reaction tube was measured 6 hours after the start of the mixed gas flow. The product was also analyzed by gas chromatography.

[0184] From the obtained results, the methanol conversion rate (%), p-xylene selectivity (%), and BTX yield were calculated using the following equations (2), (3), and (4), respectively.

[0185] Methanol conversion rate (%) = {([methanol] in - [methanol] out) / [methanol] in} × 100 (2) In the above formula (2), [methanol] in is the methanol concentration (v / v %) at the inlet of the fixed-bed flow reactor, and [methanol] out is the methanol concentration (v / v %) at the outlet of the fixed-bed flow reactor.

[0186] p-xylene selectivity (%)=([p-xylene]out / [xylene]out)×100 (3) In the above formula (3), [p-xylene]out is the total number of moles (mol) of carbon atoms contained in p-xylene at an outlet of the fixed-bed flow-type reactor tube, and [xylene]out is the total number of moles (mol) of carbon atoms contained in xylenes (p-xylene, o-xylene, and m-xylene) at an outlet of the fixed-bed flow-type reactor tube.

[0187] BTX yield (%) = ([BTX] out / [product] out) × methanol conversion (4) In the above formula (4), [BTX] out is the total number of moles (mol) of carbon atoms contained in benzene, xylene (p-xylene, o-xylene, and m-xylene), and toluene at an outlet of the fixed-bed flow-type reactor tube, [product] out is the total number of moles (mol) of carbon atoms contained in the product (all components in the product) at the outlet of the fixed-bed flow-type reactor tube, and the methanol conversion is the methanol conversion (%) calculated from the above formula (2).

[0188]

[0189] As shown in Tables 3 and 4 above, the zeolites of the examples were able to increase the p-xylene selectivity in the production of xylene by reforming alcohol, compared to the zeolites of the comparative examples.

Claims

1. A porous porous material containing one or more predetermined elements selected from the group consisting of magnesium, calcium, titanium, boron and phosphorus, and having a total pore volume of 0.21 cm ３ / g or less.

2. The zeolite according to claim 1, wherein the zeolite having a 10-membered oxygen ring structure is an MFI type zeolite, a MEL type zeolite, a TON type zeolite, an STF type zeolite, an MTT type zeolite, an MWW type zeolite, or a ZSM-48 zeolite.

3. The zeolite according to claim 1 or 2, characterized in that the molar ratio of silica to alumina is 10 or more and 250 or less.

4. The zeolite according to any one of claims 1 to 3, further comprising one or more other elements selected from the group consisting of silver, zinc, gallium and iron.

5. The zeolite according to any one of claims 1 to 4, wherein the specified element is supported on at least the outer surface.

6. In the difference spectrum obtained by subtracting the IR spectrum of the zeolite before 2,6-di-tert-butylpyridine adsorption from the IR spectrum of the zeolite to which 2,6-di-tert-butylpyridine has been adsorbed, －１ 1620cm or more －１ 1630 cm for the maximum intensity of the peak having a peak top in the range －１ More than 1650cm －１ 6. The zeolite according to claim 1, wherein the ratio of the maximum intensities of the peaks having peak tops in the following ranges is greater than 1.5:

7. Treatment temperature: 420° C., treatment pressure (gauge pressure): 0.2 MPa, treatment time: 6 hours, and methanol weight hourly space velocity: 1.0 Hr. －１ 7. The zeolite according to claim 1, wherein the p-xylene selectivity is 40% or more when the zeolite is contacted with a mixed gas of nitrogen and methanol under the above-mentioned conditions.

8. A catalyst for alcohol reforming, comprising the zeolite according to any one of claims 1 to 7.

9. A method for producing xylene, comprising contacting a zeolite according to any one of claims 1 to 7 with a fluid containing an alcohol.

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