Crystalline metallosilicate belonging to ZSM-48 family and method for producing same

Abstract

The purpose of the present invention is to provide at least one among: a crystalline metallosilicate belonging to ZSM-48, which is suitable for a substrate of at least one catalyst among a catalyst for an isomerization reaction and a catalyst for an MTO reaction; a method for producing the same; a catalyst for an isomerization reaction, the catalyst comprising the same; a catalyst for an MTO reaction, the catalyst comprising the same; a method for producing a branched paraffin using a catalyst for an isomerization reaction; and a method for producing an olefin using a catalyst for an MTO reaction.　This crystalline metallosilicate belonging to a ZSM-48 family is characterized by: containing iron atoms and aluminum atoms as metal atoms constituting a skeleton structure; having an average crystal grain diameter of at most 0.1 μm; and having a peak having a peak top at 310-370ºC in an ammonia temperature-programmed desorption spectrum measured by a NH3-TPD method.

Description

Crystalline metallosilicates belonging to the ZSM-48 family and methods for producing the same

[0001] This disclosure relates to crystalline metallosilicates belonging to the ZSM-48 family and methods for producing the same.

[0002] Zeolites belonging to the ZSM-48 family (hereinafter also referred to as "ZSM-48 zeolites") are zeolites having a one-dimensional pore with a 10-membered oxygen ring. Among the ZSM-48 zeolites, there are aluminosilicates in which the atoms constituting the skeletal structure consist of aluminum and silicon. ZSM-48 zeolites that are aluminosilicates are known to be usable as a base material for catalysts for isomerizing straight-chain paraffins (normal paraffins) into branched paraffins (hereinafter also referred to as "isomerization reaction catalysts") (for example, Patent Document 1), and as a base material for catalysts for producing olefins from methanol (hereinafter also referred to as "MTO reaction catalysts") (for example, Patent Document 2).

[0003] International Publication No. 2009 / 001572, International Publication No. 2022 / 063992

[0004] Isomerization catalysts are generally used at the reaction temperature that yields the highest branched paraffin (hereinafter also referred to as the "optimal reaction temperature") in order to increase the yield of the branched paraffin produced (hereinafter also referred to as the "branched paraffin yield"). Therefore, the substrate of the isomerization catalyst is required to have a high branched paraffin yield at the optimal reaction temperature.

[0005] Furthermore, olefins produced by MTO reaction catalysts are used as various chemical raw materials. Among the olefins produced by MTO reaction catalysts, branched olefins with four carbon atoms (hereinafter also referred to as "C4 branched olefins") are particularly easy to use as various chemical raw materials. For this reason, the substrate for MTO reaction catalysts is required to have a high selectivity for C4 branched olefins.

[0006] The present disclosure aims to provide a crystalline metallosilicate belonging to the ZSM-48 family suitable as a substrate for at least one of the catalysts for isomerization reactions and MTO reactions, a method for producing the same, a catalyst for isomerization reactions containing the same, a catalyst for MTO reactions containing the same, a method for producing branched paraffin using the catalyst for isomerization reactions, and a method for producing olefin using the catalyst for MTO reactions.

[0007] The present invention is as described in the claims, and the gist of this disclosure is as follows: [1] Contains iron atoms and aluminum atoms as metal atoms constituting the skeletal structure, with an average crystal grain size of 0.1 μm or less, and NH ３ - A crystalline metallosilicate belonging to the ZSM-48 family, characterized in that the ammonia temperature-induced desorption spectrum measured by the TPD method has a peak with a peak top at 310°C or higher and 370°C or lower. [2] A crystalline metallosilicate belonging to the ZSM-48 family as described in [1], wherein the peak has a peak top at 320°C or higher and 365°C or lower. [3] A crystalline metallosilicate belonging to the ZSM-48 family as described in [1] or [2], wherein the molar ratio of iron to aluminum is 0.1 or higher. [4] A crystalline metallosilicate belonging to the ZSM-48 family as described in any one of [1] to [3], wherein the ratio of the amount of Brønsted acid to the total amount of acid, which is the sum of Brønsted acid and Lewis acid, is 55% or higher. [5] A crystalline metallosilicate belonging to the ZSM-48 family according to any one of [1] to [4], wherein the acid content is 0.01 mmol / g or more and 1.00 mmol / g or less. [6] A crystalline metallosilicate belonging to the ZSM-48 family according to any one of [1] to [5], wherein the aspect ratio is 10 or less. [7] A crystalline metallosilicate belonging to the ZSM-48 family according to any one of [1] to [6], wherein it has at least the powder X-ray diffraction peaks shown in the table below. [8] A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to any one of [1] to [7], comprising a crystallization step of crystallizing a raw material composition comprising amorphous aluminosilicate, an iron source, a hexamethonium source, an alkali source, and water in the presence of a seed crystal. [9] A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to [8], wherein the hexamethonium source is hexamethonium dihydroxyl.

[10] A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to [8] or [9], wherein the raw material composition further comprises an alumina source other than the amorphous aluminosilicate.

[11] A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to any one of [8] to

[10] , wherein the raw material composition does not contain a silica source other than the amorphous aluminosilicate.

[12] An isomerization catalyst for isomerizing a linear paraffin to a branched paraffin, comprising a crystalline metallosilicate belonging to the ZSM-48 family as described in any one of [1] to [7] above.

[13] An MTO reaction catalyst for producing an olefin from methanol, comprising a crystalline metallosilicate belonging to the ZSM-48 family as described in any one of [1] to [7] above.

[14] A method for producing a branched paraffin, comprising the step of contacting the isomerization catalyst described in

[12] with a fluid containing a linear paraffin and hydrogen.

[15] A method for producing an olefin, comprising the step of contacting the MTO reaction catalyst described in

[13] with a fluid containing methanol.

[0008] This disclosure provides at least one of the following: a crystalline metallosilicate belonging to ZSM-48 suitable as a substrate for at least one of the catalysts for isomerization reactions and MTO reactions; a method for producing the same; a catalyst for isomerization reactions containing the same; a catalyst for MTO reactions containing the same; a method for producing branched paraffin using the catalyst for isomerization reactions; and a method for producing olefin using the catalyst for MTO reactions.

[0009] Figure 1 shows the ammonia desorption spectrum at high temperature for Example 1. Figure 2 shows the ammonia desorption spectrum at high temperature for Example 2. Figure 3 shows the ammonia desorption spectrum at high temperature for Example 3. Figure 4 shows the ammonia desorption spectrum at high temperature for Example 4. Figure 5 shows the ammonia desorption spectrum at high temperature for Comparative Example 1.

[0010] Hereinafter, an example of an embodiment of a crystalline metallosilicate belonging to the ZSM-48 family of this disclosure (hereinafter also referred to as "ZSM-48 metallosilicate") will be described. The terms used in this embodiment are as follows.

[0011] A "zeolite" is a compound in which the skeletal atoms (hereinafter also referred to as "T atoms") have a regular structure mediated by oxygen (O), and the T atoms consist of at least one of a metallic atom and a metalloid atom. Examples of metallic atoms include one or more selected from the group consisting of aluminum (Al), titanium (Ti), iron (Fe), zinc (Zn), gallium (Ga), and tin (Sn). 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).

[0012] A "zeolite-like substance" is a compound in which the T atom has a regular structure mediated by oxygen, and which contains at least one atom other than a metal or metalloid in the T atom. Examples of zeolite-like substances include aluminophosphate (AlPO) and silicoaluminophosphate (SAPO), which are complex phosphorus compounds containing phosphorus (P) as the T atom. In this embodiment, for convenience, a "zeolite-like substance" is distinguished from a "zeolite" in which the T atom consists of at least one of a metal atom and a metalloid atom.

[0013] A "metallosilicate" is a composite oxide having a structure consisting of repeating networks of metal atoms (hereinafter also referred to as "M atoms") and silicon (Si) mediated by oxygen (O), and containing aluminum (Al) and metal atoms other than aluminum as M atoms. Among metallosilicates, those having crystalline XRD peaks in their XRD pattern are called "crystalline metallosilicates," and those not having crystalline XRD peaks are called "amorphous metallosilicates." In this embodiment, a zeolite containing M atoms and silicon atoms as T atoms, and containing aluminum (Al) and metal atoms other than aluminum as M atoms, is considered a "crystalline metallosilicate."

[0014] An "aluminosilicate" is a composite oxide having a structure consisting of repeating networks of M atoms and silicon (Si) mediated by oxygen (O), where the M atoms are substantially composed solely of aluminum (Al). Among aluminosilicates, those with crystalline XRD peaks in their XRD pattern are called "crystalline aluminosilicates," while those without crystalline XRD peaks are called "amorphous aluminosilicates." In this embodiment, a zeolite containing M atoms and silicon atoms as T atoms, where the M atoms are substantially composed solely of aluminum (Al), is considered a "crystalline aluminosilicate." Note that "substantially composed solely of aluminum (Al)" means that no metal atoms other than aluminum (Al) are detected (below the detection limit).

[0015] The "regular structure" in zeolites and zeolite-like materials refers to the skeletal structure specified by the skeletal structure code (hereinafter simply referred to as the "structure code") defined by the Structure Commission of the International Zeolite Association (hereinafter also referred to as "IZA"), and the intercrystalline structure (skeletal structure) described on the IZA homepage "http: / / www.iza-structure.org / databases / ". For example, "ZSM-48" is a zeolite having an intercrystalline structure (skeletal structure) composed of an intercrystalline body consisting of polymorph ZSM-48_A and polymorph ZSM-48_B.

[0016] In this embodiment, the "ZSM-48 family" refers to a group of multiple ZSM-48s with different ratios of polymorph ZSM-48_A and polymorph ZSM-48_B (hereinafter also referred to as the "interlinking ratio"). Any zeolite (ZSM-48) within this group is referred to as a "zeolite belonging to the ZSM-48 family." Among the "zeolites belonging to the ZSM-48 family," those that correspond to crystalline metallosilicates are called "crystalline metallosilicates belonging to the ZSM-48 family," and those that correspond to crystalline aluminosilicates are called "crystalline aluminosilicates belonging to the ZSM-48 family." The interlinking ratio in the "zeolites belonging to the ZSM-48 family" represents the respective ratios of polymorph ZSM-48_A or polymorph ZSM-48_B in the sum of the ratios of polymorph ZSM-48_A and polymorph ZSM-48_B, which is 100%. For example, in the case of the ZSM-48 family where the twinning ratio of polymorph ZSM-48_A is 60%, the twinning ratio of polymorph ZSM-48_B within the same ZSM-48 family is 40%. Note that the "ZSM-48 family" includes polymorphs where the ratio of ZSM-48_A is 0% and polymorph ZSM-48_B is 0%, encompassing ZSM-48 with all twinning ratios.

[0017] The skeletal structure of zeolites can be identified by comparing it with the powder X-ray diffraction (hereinafter also referred to as "XRD") patterns of known ZSM-48 zeolites and the XRD patterns obtained by simulations using DIFFaX (hereinafter also referred to as "DIFFaX patterns"). An example of an XRD pattern for identifying "ZSM-48" is the XRD pattern described in the 1-dimensional stacking distributor of Intergrowth on the IZA Structural Committee homepage (http: / / asia.iza-structure.org / databases / ) (http: / / asia.iza-structure.org / IZA-SC / DO_structures / DO_pow_plot_difffax.php?poli_mix=ZSM-48_A-ZSM-48_B) (hereinafter also referred to as the "reference pattern").

[0018] In this embodiment, the XRD pattern is obtained by XRD measurement under the following conditions. The XRD pattern can be measured using a general powder X-ray diffractometer (e.g., Ultima IV Protectus, manufactured by Rigaku). Acceleration current / voltage: 40 mA / 40 kV Source: CuKα rays (λ = 1.5405 Å) Measurement mode: Continuous scan Scan conditions: 40° / min Measurement range: 2θ = 3° to 43° Divergence longitudinal limiting slit: 10 mm Divergence / incident slit: 1° Receiving slit: open Receiving solar slit: 5° Detector: Semiconductor detector (D / teX Ultra) Filter: Ni filter

[0019] Crystalline XRD peaks are peaks whose peak top 2θ is identified and detected in XRD pattern analysis using general analysis software (e.g., SmartLab Studio II, manufactured by Rigaku). A crystalline XRD peak with a full width at half maximum (FMAX) of 2θ = 0.50° or less can be exemplified. The following conditions can be used for XRD pattern analysis: Fitting conditions: Automatic, background refined, dispersed pseudo-Voigt function (peak shape) Background removal method: Fitting method Kα2 removal method: Kα1 / Kα2 ratio = 0.497 Smoothing method: B-Spline curve Smoothing conditions: Second derivative method, σ cut value = 3, χ threshold = 1.5

[0020] "Average grain size" refers to the average particle size of primary particles. Primary particles are the smallest particles that can be observed independently under scanning electron microscopy (SEM) observation under the following conditions, and are different from aggregated particles (agglutinative particles) formed by the aggregation of multiple particles (multiple primary particles). SEM observation can be performed using a general scanning electron microscope (for example, instrument name: JSM-IT200, manufactured by JEOL Ltd.). Acceleration voltage: 5kV Magnification: 10,000±5,000x

[0021] To measure the "average crystal grain size," first, arbitrarily select 100 ± 10 primary particles whose contours are observed without interruption in the SEM observation image. Measure the distance between the two parallel lines that are tangent to the contour of each selected primary particle, and calculate the average value of this distance. This average value is then used as the average crystal grain size. The number of SEM observation images should be sufficient to observe the aforementioned number of primary particles; one or more SEM observation images may be used.

[0022] Alumina (Al ２ O ３ Silica (SiO) relative to aluminum (in terms of equivalent value) ２ ) Molar ratio of silicon (hereinafter referred to as "SiO ２ / Al ２ O ３ The composition in this embodiment, such as the molar ratio (also called the "molar ratio") and the molar ratio of iron to aluminum (hereinafter also called the "Fe / Al molar ratio"), can be determined using a general inductively coupled plasma emission spectrometer (for example, OPTIMA3300DV, manufactured by PERKIN ELMER). For compositional analysis, a sample solution obtained by dissolving the sample in a mixed aqueous solution of hydrofluoric acid and nitric acid can be used.

[0023] The ZSM-48 metallosilicate of this embodiment will be described below. This 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.

[0024] The ZSM-48 metallosilicate of this embodiment contains iron atoms and aluminum atoms as metal atoms (M atoms) constituting the skeletal structure, has an average crystal grain size of 0.1 μm or less, and is NH ３ - In the ammonia temperature-controlled desorption spectrum measured by the TPD method, there is a peak with its peak top between 310°C and 370°C.

[0025] The metallosilicate belonging to ZSM-48 of the present embodiment contains iron atoms and aluminum atoms as metal atoms (M atoms) constituting the framework structure. That is, the metallosilicate belonging to ZSM-48 of the present embodiment is a crystalline metallosilicate in which T atoms containing iron atoms, aluminum atoms, and silicon atoms are bonded through oxygen atoms to form the framework structure of ZSM-48.

[0026] The metallosilicate belonging to ZSM-48 of the present embodiment contains iron atoms and aluminum atoms as M atoms constituting the framework structure, and thus is suitable as a base material (hereinafter, also referred to as "catalyst base material") for at least one of the catalyst for isomerization reaction and the catalyst for MTO reaction. For example, when the metallosilicate belonging to ZSM-48 of the present embodiment is applied as a base material for the catalyst for isomerization reaction, the ratio of the number of moles of silicon in terms of silica (SiO ２ O ３ ) to the total number of moles of trivalent M atoms in terms of oxide (M ２ ) (hereinafter, also referred to as "SiO ２ / M ２ O ３ molar ratio") is the same as that of a crystalline aluminosilicate belonging to the ZSM-48 family (hereinafter, also referred to as "ZSM-48 aluminosilicate") used as a base material, and the yield of branched paraffin at the optimum reaction temperature can be increased. According to a preferred embodiment of the metallosilicate belonging to ZSM-48 of the present embodiment, in addition to the first effect described above, compared with the case of using a ZSM-48 aluminosilicate having the same SiO ２ / Al ２ O ３ molar ratio as a base material, at least one of the second effect that the yield of branched paraffin at the optimum reaction temperature is increased and the third effect that the optimum reaction temperature at which the yield of branched paraffin is the highest can be lowered can be further obtained. Also, for example, when the metallosilicate belonging to ZSM-48 of the present embodiment is applied as a base material for the catalyst for MTO reaction, SiO ２ / Al ２ O ３ molar ratio is the same as that of a ZSM-48 aluminosilicate used as a base material, and the yield of branched paraffin at the optimum reaction temperature can be increased. ２ / M ２ O ３ A fourth effect can be obtained, which is an improved selectivity for C4 branched olefins, compared to the case where a ZSM-48 aluminosilicate with a similar molar ratio is used as the base material. Furthermore, according to a preferred embodiment of the ZSM-48 metallosilicate of this embodiment, in addition to the fourth effect described above, SiO ２ / Al ２ O ３ A fifth effect can also be obtained, which is an improved selectivity for C4 branched olefins, compared to the case where a ZSM-48 aluminosilicate with a similar molar ratio is used as the base material.

[0027] Note that SiO ２ / Al ２ O ３ The molar ratio being similar means that the SiO of the comparison target (i.e., the ZSM-48 metallosilicate in this embodiment) is similar. ２ / Al ２ O ３ When compared to the molar ratio, the difference is less than or equal to 10 in absolute value (i.e., ±10), and SiO ２ / M ２ O ３ The molar ratio being similar means that the SiO of the comparison target (i.e., the ZSM-48 metallosilicate in this embodiment) is similar. ２ / M ２ O ３ This refers to a situation where the difference between the molar ratio and the result is less than or equal to 10 in absolute value (i.e., ±10).

[0028] The reason why the ZSM-48 metallosilicate of this embodiment, which contains iron and aluminum atoms as M atoms constituting its skeletal structure, is suitable as a catalyst substrate is not clear. However, since iron atoms have a lower acid strength than aluminum atoms, the inclusion of iron atoms in addition to aluminum atoms as M atoms constituting the skeletal structure suppresses cracking (catalytic decomposition) of the raw materials (linear paraffins and methanol) caused by excessively high acid strength, and results in an appropriate acid strength that facilitates the formation of branched paraffins and C4 branched olefins. As a result, it is thought that the yield of branched paraffins at the optimal reaction temperature is improved, and the selectivity of C4 branched olefins is improved.

[0029] The branched paraffin yield (%) can be determined by multiplying the volume ratio of branched paraffin to the total product produced by the isomerization of linear paraffin by the conversion rate of the linear paraffin used as a reaction material. The conversion rate (%) of linear paraffin can be determined by multiplying the volume ratio of converted linear paraffin to the linear paraffin used as a reaction material by 100. The selectivity of C4 branched olefins can be determined by multiplying the ratio of the number of moles of carbon atoms in the generated C4 branched olefin to the total number of moles of carbon atoms in the aliphatic hydrocarbon with 4 carbon atoms produced from methanol (hereinafter also referred to as "C4 hydrocarbon") by 100.

[0030] The ZSM-48 metallosilicate of this embodiment may contain other metal atoms as long as it contains at least iron atoms and aluminum atoms as M atoms constituting the framework structure. From the viewpoint of making it more suitable as a catalyst substrate, it is preferable that the ZSM-48 metallosilicate of this embodiment consists substantially only of iron atoms and aluminum atoms as M atoms constituting the framework structure, and it is preferable that the T atoms constituting the framework structure consist substantially only of iron atoms, aluminum atoms, and silicon atoms. Note that consisting substantially only of predetermined atoms means that atoms other than the predetermined atoms are not detected (below the detection limit).

[0031] The ZSM-48 metallosilicate in this embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, SiO ２ / Al ２ O ３ The molar ratio is preferably 40 or more, 60 or more, or 80 or more, and preferably 10,000 or less, 5,000 or less, or 3,000 or less. ２ / Al ２ O ３ The combination of the upper and lower limits of the molar ratio is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, SiO ２ / Al ２ O ３ The molar ratio is preferably 40 to 10,000, more preferably 60 to 5,000, and even more preferably 80 to 3,000.

[0032] The ZSM-48 metallosilicate of this embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, the Fe / Al molar ratio is preferably 0.05 or more, 0.10 or more, or 0.15 or more, and preferably 40 or less, 30 or less, or 20 or less. The combination of the upper and lower limits of the Fe / Al molar ratio described above is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, the Fe / Al molar ratio is preferably 0.05 or more and 40 or less, more preferably 0.10 or more and 30 or less, and even more preferably 0.15 or more and 20 or less.

[0033] The ZSM-48 metallosilicate in this embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, alumina (Al ２ O ３ ) Aluminum and iron(III) oxide (Fe ２ O ３ Silica (SiO) relative to the total number of moles of iron (converted to ) ２ ) Ratio of the number of moles of silicon converted to (hereinafter referred to as "SiO ２ / (Al ２ O ３ +Fe ２ O ３The molar ratio is preferably 40 or more, 50 or more, or 60 or more, and preferably 300 or less, 200 or less, or 100 or less. ２ / (Al ２ O ３ +Fe ２ O ３ The combination of the upper and lower limits of the molar ratio is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, SiO ２ / (Al ２ O ３ +Fe ２ O ３ The molar ratio is preferably 40 to 300, more preferably 50 to 200, and even more preferably 60 to 100.

[0034] The ZSM-48 metallosilicate of this embodiment has an average crystal grain size of 0.1 μm or less. This average crystal grain size of 0.1 μm or less makes the ZSM-48 metallosilicate suitable as a substrate for at least one of the isomerization reaction catalysts and the MTO reaction catalysts. Although the reason for this is unclear, it is thought that the average crystal grain size of the ZSM-48 metallosilicate of this embodiment, being 0.1 μm or less, allows acid sites near the pore openings, which are considered to be catalytic active sites, to be more easily exposed on the surface of the ZSM-48 metallosilicate. This facilitates contact between the catalytic active sites (acid sites) and the raw materials (linear paraffins and methanol), resulting in improved branched paraffin yield at the optimal reaction temperature and improved selectivity for C4 branched olefins.

[0035] In the ZSM-48 metallosilicate of this embodiment, the average crystal grain size may be 0.1 μm or less, but from the viewpoint of making it more suitable as a catalyst substrate, it is preferably 0.08 μm or less, and more preferably 0.06 μm or less. The lower limit of the average crystal grain size is not particularly limited, but for example, it may be 0.01 μm or more, or 0.03 μm or more. The above-mentioned combination of upper and lower limits of the average crystal grain size is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, the average crystal grain size is preferably 0.01 μm or more and 0.1 μm or less, more preferably 0.03 μm or more and 0.1 μm or less, and even more preferably 0.03 μm or more and 0.08 μm or less.

[0036] The ZSM-48 metallosilicate of this embodiment is not particularly limited, but it is preferable that the aspect ratio (L1 / L2) determined by the following formula (1) is 30 or less, 10 or less, 5 or less, or 3 or less. The lower limit of the aspect ratio (L1 / L2) is arbitrary, but for example, it may be 1 or more, or 1.1 or more. The above-mentioned combination of upper and lower limits of the aspect ratio (L1 / L2) is arbitrary, but the aspect ratio (L1 / L2) is preferably 1 or more and 30 or less, more preferably 1 or more and 10 or less, even more preferably 1.1 or more and 5 or less, and particularly preferably 1.1 or more and 3 or less. When the aspect ratio (L1 / L2) of the ZSM-48 metallosilicate of this embodiment is within the above-mentioned range, the raw materials (linear paraffins or methanol) come into contact more easily with the acid sites that become catalytic active sites, making it more suitable as a catalyst substrate. Aspect ratio [-] = Average longest diameter L1 [μm] / Average shortest diameter L2 [μm] ... (1)

[0037] In equation (1) above, the average longest diameter L1 [μm] can be determined by arbitrarily selecting 100 ± 10 primary particles whose contours are observed without interruption in the SEM observation image, measuring the distance between the two parallel lines that are tangent to the contour of each selected primary particle to obtain the longest distance (hereinafter also referred to as the "longest diameter"), and averaging these values. Similarly, the average shortest diameter L2 [μm] in equation (1) above can be determined by arbitrarily selecting 100 ± 10 primary particles whose contours are observed without interruption in the SEM observation image, measuring the distance between the two parallel lines that are tangent to the contour of each selected primary particle to obtain the shortest distance (hereinafter also referred to as the "shortest diameter"), and averaging these values. As is clear from the average longest diameter L1 and average shortest diameter L2, the aspect ratio (L1 / L2) obtained by equation (1) above is the aspect ratio of the primary particles and differs from the aspect ratio of the secondary aggregates (aggregates) formed by the aggregation of primary particles. The number of SEM observation maps used to determine the average longest diameter L1 and average shortest diameter L2 should be such that the aforementioned number of primary particles can be observed; one or more SEM observation maps may be used. Furthermore, the SEM observation method (conditions) is the same as that used for calculating the average crystal grain size, so a detailed explanation is omitted.

[0038] The ZSM-48 metallosilicate of this embodiment is NH ３- In the ammonia thermal desorption spectrum measured by the TPD method (ammonia thermal desorption method (see Measurement of Solid Acid Properties by Ammonia Thermal Desorption Method, Catalysts, vol. 42, p. 218 (2000))), there is a peak with its peak top between 310°C and 370°C. The ZSM-48 metallosilicate of this embodiment has a peak with its peak top between 310°C and 370°C in the ammonia thermal desorption spectrum, making it suitable as a substrate for at least one of the catalysts for isomerization reactions and MTO reactions. The ammonia thermal desorption spectrum usually contains two peaks: a peak with its peak top in the range below 300°C (hereinafter also referred to as the "L peak") and a peak with its peak top in the range above 300°C (hereinafter also referred to as the "H peak"). Of these peaks, the H peak represents the amount of ammonia released from the acid sites (acid sites that become catalytically active sites) on the zeolite skeleton structure. The temperature at the top of the H peak represents the energy (temperature) required to release the ammonia adsorbed on the acid sites on the zeolite skeleton structure. Therefore, the temperature at the top of the H peak functions as an indicator of the acid strength of the acid sites that become catalytically active sites. Specifically, the higher the temperature at the top of the H peak, the higher the acid strength of the zeolite, and the lower the temperature at the top of the H peak, the lower the acid strength of the zeolite. With the temperature at the top of the H peak between 310°C and 370°C, the ZSM-48 metallosilicate of this embodiment suppresses cracking (catalytic decomposition) of the raw materials (linear paraffins and methanol) caused by excessively high acid strength, and has an appropriate acid strength that facilitates the formation of linear paraffins and C4 branched olefins. As a result, it is thought that the yield of branched paraffins at the optimal reaction temperature is improved, and the selectivity of C4 branched olefins is improved.

[0039] The ZSM-48 metallosilicate of this embodiment may have only one H peak in the ammonia temperature-induced desorption spectrum, or it may have two or more H peaks. If the ZSM-48 metallosilicate of this embodiment has two or more H peaks, at least one of those H peaks should have its peak top at 310°C or higher and 370°C or lower. From the viewpoint of making it more suitable as a catalyst substrate, it is preferable that the ZSM-48 metallosilicate of this embodiment has only one H peak, and that the peak top of that H peak is at 310°C or higher and 370°C or lower. The peak top of the H peak refers to the portion where the spectral intensity of the H peak shows its maximum value.

[0040] In the ZSM-48 metallosilicate of this embodiment, the temperature of the peak top of the H peak may be 310°C or higher and 370°C or lower, but from the viewpoint of making it more suitable as a catalyst substrate, it is preferably 320°C or higher, or 321°C or higher, and preferably 365°C or lower, 360°C or lower, or 358°C or lower. The combination of the upper and lower limits of the temperature of the peak top of the H peak is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, the temperature of the peak top of the H peak is preferably 320°C or higher and 365°C or lower, more preferably 320°C or higher and 360°C or lower, and even more preferably 321°C or higher and 358°C or lower.

[0041] The ammonia temperature-induced desorption spectrum was obtained using a general catalyst analyzer (e.g., instrument name: BELCAT II, ​​manufactured by Microtrac-Bell Co., Ltd.) and NH ３- It can be measured by the TPD method. Specifically, a measurement sample (zeolite) on which ammonia has been saturated adsorbed at room temperature (25°C) is heated in an inert gas at 100°C for 1 hour to remove ammonia not adsorbed on the measurement sample from the measurement atmosphere. Then, the temperature is increased from 100°C to 600°C at a heating rate of 10°C / min, and the amount of ammonia released from the measurement sample during the heating process (hereinafter also referred to as "released ammonia amount") [ mmol] is measured over time to obtain an ammonia temperature-activated desorption spectrum. The temperature of the peak top of the H peak can be determined by identifying the temperature at which the peak top appears for the H peak included in the measured ammonia temperature-activated desorption spectrum. For the measurement sample on which ammonia has been saturated adsorbed, zeolite pretreated in an inert gas at 500°C for 1 hour can be used. As for the inert gas used for pretreatment, at least one of helium and argon can be mentioned, and helium is preferred.

[0042] The ZSM-48 metallosilicate of this embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, it is preferable that it has at least the XRD peaks shown in Table 2 below, and more preferably that it has at least the XRD peaks shown in Table 3 below. In this embodiment, "having the XRD peaks shown in the table" means that a peak top is located within the range of lattice plane spacing d (Å) shown in the table, and a peak having the relative peak intensity shown in the table can be confirmed in the XRD pattern.

[0043]

[0044]

[0045] In this embodiment, if the ZSM-48 metallosilicate has the XRD peaks shown in Table 2, it is preferable that, in the range of interplanar spacing d from 2.00 Å to 29.42 Å, it does not contain any peaks with a relative peak intensity exceeding 10% other than the XRD peaks shown in Table 2. Furthermore, if the ZSM-48 metallosilicate has the XRD peaks shown in Table 3, it is preferable that, in the range of interplanar spacing d from 2.00 Å to 29.42 Å, it does not contain any peaks with a relative peak intensity of 3% or more other than the XRD peaks shown in Table 3. Note that XRD peaks with a relative peak intensity of less than 3% do not need to be considered for the identification of the skeletal structure.

[0046] Here, the XRD pattern does not represent the skeletal structure as individual, independent XRD peaks, but rather as a group of XRD peaks with specific relative intensities, thereby indicating the skeletal structure of a single zeolite. A change in the lattice plane spacing and relative intensity of the XRD peaks means a change in its skeletal structure. Therefore, the skeletal structure of a zeolite can be identified by a group of XRD peaks as shown in Tables 2 and 3.

[0047] The ZSM-48 metallosilicate in this embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, the acid content is preferably 0.01 mmol / g or more, 0.05 mmol / g or more, or 0.10 mmol / g or more, and preferably 1.00 mmol / g or less, 0.50 mmol / g or less, or 0.35 mmol / g or less. The combination of the upper and lower limits of the acid content described above is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, the acid content is preferably 0.01 mmol / g or more and 1.00 mmol / g or less, more preferably 0.05 mmol / g or more and 0.50 mmol / g or less, and even more preferably 0.10 mmol / g or more and 0.35 mmol / g or less.

[0048] The acid content is the total amount of Brønsted acid and Lewis acid per unit mass of zeolite. The acid content of ZSM-48 zeolite (ZSM-48 metallosilicate) can be determined by adsorbing pyridine onto the acid sites (Brønsted acid and Lewis acid) of the ZSM-48 zeolite and quantifying the amount of pyridine adsorbed onto the acid sites. Pyridine has the property of adsorbing onto the acid sites (Brønsted acid and Lewis acid) present in ZSM-48 zeolite, and since it is smaller than the pores of the ZSM-48 zeolite, it adsorbs onto the acid sites (Brønsted acid and Lewis acid) on the outer surface and inside the pores of the ZSM-48 zeolite. Therefore, the acid content per unit mass of ZSM-48 zeolite can be determined by quantifying the amount of pyridine adsorbed onto the acid sites of the ZSM-48 zeolite.

[0049] The acid content of ZSM-48 zeolite (ZSM-48 metallosilicate) can be determined specifically by the following method. First, the difference spectrum obtained by subtracting the infrared absorption spectrum of the ZSM-48 zeolite before pyridine adsorption (hereinafter also called the "background spectrum") from the infrared absorption spectrum of the ZSM-48 zeolite with pyridine adsorbed (hereinafter also called the "adsorption spectrum") is 1640 ± 10 cm⁻¹. －１ The integrated intensity of the peak attributed to Brønsted acid (hereinafter also referred to as "acid B"), which has its peak top at 1450 ± 10 cm², and 1450 ± 10 cm². －１ The integral intensity of the peak attributed to the Lewis acid (hereinafter also referred to as "L acid") having a peak top is determined. The amount of B acid in the zeolite per unit mass (hereinafter also referred to as "B acid amount") is determined by substituting the determined integral intensity of the peak attributed to the L acid into the following equation (2-A), and the amount of L acid in the zeolite per unit mass (hereinafter also referred to as "L acid amount") is determined by substituting the determined integral intensity of the peak attributed to the L acid into the following equation (2-B). The acid amount can be determined by adding these B acid amount and L acid amount.

[0050] B acid amount [mmol / g] =S ａｒｅａ ×I Ｂａｃｉｄ / ( S ｍａｓｓ ×MＢａｃｉｄ ),..., (2-A) In the above formula (2-A), S ａｒｅａ represents the area of the measurement sample [cm ２ , S ｍａｓｓ represents the mass of the measurement sample [mg], M Ｂａｃｉｄ represents the molar absorption coefficient of Bronsted acid [cm / μmol], I Ｂａｃｉｄ represents the integrated intensity [-] of the peak attributed to Bronsted acid. Note that for the area of the measurement sample (S ａｒｅａ ) and the mass of the measurement sample (S ｍａｓｓ ), the area [cm ２ of the sample press-molded by the method described later and the mass [mg] of the sample after the FT-IR measurement described later can be used respectively, and for the molar absorption coefficient of Bronsted acid, 1.67 [cm / μmol] can be used.

[0051] Amount of Lewis acid [mmol / g] = S ａｒｅａ ×I Ｌａｃｉｄ / (S ｍａｓｓ ×M Ｌａｃｉｄ ),..., (2-B) In the above formula (2-B), S ａｒｅａ represents the area of the measurement sample [cm ２ , S ｍａｓｓ represents the mass of the measurement sample [mg], M Ｌａｃｉｄ represents the molar absorption coefficient of Lewis acid [cm / μmol], I Ｌａｃｉｄ [[ID=3८]]represents the integrated intensity [-] of the peak attributed to Lewis acid. Note that for the area of the measurement sample (S ａｒｅａ ) and the mass of the measurement sample (S ｍａｓｓ ), the area [cm ２ of the sample press-molded by the method described later and the mass [mg] of the sample after the FT-IR measurement described later can be used respectively, and for the molar absorption coefficient of Lewis acid, 2.22 [cm / μmol] can be used.

[0052] The background spectrum and the adsorption spectrum can be measured by an FT-IR device (FT / IR-6X, manufactured by JASCO Corporation). In the measurement of the background spectrum, a measurement sample (zeolite) press-molded at a gauge pressure of 2.0 T to have a cylindrical shape with an area of 0.785 cm ２ (that is, a cylindrical shape with a diameter of 1 mm) is filled into a heating transmission cell, and 1.0×10－２ Under a vacuum of less than Pa, it is pretreated at 450 °C for 2 hours. After the pretreatment, it is cooled to 150 °C under a vacuum condition of 1.0×10 －２ Pa or less, and the background spectrum may be measured under the following measurement conditions. For the measurement of the adsorption spectrum, pyridine is introduced into the heated transmission cell after the background spectrum is measured, and pyridine and the measurement sample are brought into contact under the conditions of 150 °C, 20 minutes, and 20 Pa. Then, 1.0×10 －２ The heated transmission cell is treated at 150 °C and for 30 minutes under a vacuum of Pa or less to remove excess pyridine, and then the adsorption spectrum may be measured under the following measurement conditions. Sample area : 0.785 cm ２ Measurement method : Heating transmission method Measurement temperature : 150 °C Measurement wavelength range: 800 - 4000 cm-1 Resolution : 2 cm-1 Integration times : 128 times Measurement atmosphere : Vacuum (1.0×10 －２ Pa or less)

[0053] The metallosilicate belonging to ZSM-48 of the present embodiment is not particularly limited, but from the viewpoint of making it more suitable as a catalyst substrate, the ratio of the amount of B acid to the total acid amount (hereinafter, also referred to as "B acid / total acid") obtained from the following formula (3) is preferably 55% or more, 60% or more, or 65% or more, and preferably 100% or less, 98% or less, 95% or less, 90% or less, or 80% or less. The combination of the upper and lower limits of the above-mentioned B acid / total acid is arbitrary, but from the viewpoint of making it more suitable as a catalyst substrate, the B acid / total acid is preferably 55% or more and 100% or less, more preferably 55% or more and 98% or less, even more preferably 55% or more and 95% or less, and particularly preferably 55% or more and 90% or less.

[0054] B acid / total acid [%] = amount of B acid / (amount of B acid + amount of L acid) × 100... (3) In the above formula (⑶), the amount of B acid is the amount of B acid [mmol / g] obtained from the above formula (2-A), and the amount of L acid is the amount of L acid [mmol / g] obtained from the above formula (2-B).

[0055] The ZSM-48 metallosilicate of this embodiment may contain a structure-directing agent (SDA), or it may not contain an SDA. From the viewpoint of making it more suitable as a catalyst substrate, it is preferable that the ZSM-48 metallosilicate of this embodiment does not contain an SDA. An example of an SDA that can be contained in the ZSM-48 metallosilicate of this embodiment is hexamethonium (C) １２ H ３０ [N ＋ ] ２ Examples include the following. The hexamethonium that may be contained in the ZSM-48 metallosilicate of this embodiment may be in the form of a salt. Note that substantially free of a predetermined component means that the predetermined component is not detected (below the detection limit).

[0056] The ZSM-48 metallosilicate of this embodiment is not limited to a specific cationic type, and may be any of the following types: proton type, ammonium type, potassium type, and sodium type. However, from the viewpoint of making it more suitable as a catalyst substrate, it is preferable to be of the proton type or ammonium type. Note that the cationic type being ammonium type means that the main component of the counterion for compensating the charge of the skeletal structure of the zeolite (ZSM-48 metallosilicate) (for example, a component exceeding 50% by mass) is an ammonium ion (NH₄). ４ ＋ ) means that the cation type is protonate, and the protonate type means that the main component of the counterion that compensates for the charge of the skeletal structure of the zeolite (ZSM-48 metallosilicate) (for example, the component that makes up more than 50% by mass) is a hydrogen ion (H ＋ This means that it is.

[0057] The ZSM-48 metallosilicate of this embodiment described above is suitable as a substrate for at least one of the catalysts used for isomerization reactions and MTO reactions. For example, when the ZSM-48 metallosilicate of this embodiment is applied as a substrate for an isomerization reaction catalyst, the first effect described above (SiO ２ / M ２ O ３Compared to using a ZSM-48 aluminosilicate with a similar molar ratio as a substrate, the branched paraffin yield at the optimal reaction temperature is increased. According to a preferred embodiment of the ZSM-48 metallosilicate of this embodiment, in addition to the first effect, at least one of the second and third effects described above can also be obtained. Furthermore, for example, when the ZSM-48 metallosilicate of this embodiment is applied as a substrate for an MTO reaction catalyst, the fourth effect described above (SiO ２ / M ２ O ３ Compared to the case where a ZSM-48 aluminosilicate with a similar molar ratio is used as a base material, the selectivity of the C4 branched olefin is improved. According to a preferred embodiment of the ZSM-48 metallosilicate of this embodiment, in addition to the fourth effect, the fifth effect described above can also be obtained.

[0058] Next, the method for producing the ZSM-48 metallosilicate of this embodiment will be described.

[0059] The ZSM-48 metallosilicate of this embodiment can be produced, for example, by a manufacturing method (hereinafter also referred to as "manufacturing method of this embodiment") that includes a crystallization step of crystallizing a composition (hereinafter also referred to as "raw material composition") containing amorphous aluminosilicate, an iron source, a hexamethonium source, an alkali source, and water in the presence of a seed crystal.

[0060] The raw material composition includes amorphous aluminosilicate as the silica source and alumina source. The inclusion of amorphous aluminosilicate as the silica source and alumina source results in the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate being between 310°C and 370°C. On the other hand, if amorphous aluminosilicate is not included as the silica source and alumina source, the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate will be below 310°C or above 370°C.

[0061] The raw material composition contains SiO ２ / M ２ O ３ For the purpose of adjusting the molar ratio, silica sources and alumina sources other than amorphous aluminosilicate may be included, but in the synthesis of zeolites, the SiO used as a raw material for crystallization ２ / M ２ O ３ Even with the same molar ratio, the properties and characteristics of the resulting zeolite can change depending on the raw materials used. From the viewpoint of ensuring that the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate is between 310°C and 370°C, it is preferable that the raw material composition does not contain silica sources other than amorphous aluminosilicate. That is, it is preferable that the raw material composition consists of amorphous aluminosilicate, an alumina source other than amorphous aluminosilicate, an iron source, a hexamethonium source, an alkali source, and water.

[0062] Examples of silica sources other than amorphous aluminosilicate that can be included in the raw material composition include one or more selected from the group consisting of colloidal silica, amorphous silica, sodium silicate, tetraethyl orthosilicate, precipitated silica, fumed silica, and crystalline aluminosilicate.

[0063] Other alumina sources that can be included in the raw material composition include, for example, one or more selected from the group consisting of aluminum sulfate, sodium aluminate, aluminum hydroxide, aluminum hydroxide gel, aluminum chloride, crystalline aluminosilicate, and metallic aluminum. Since the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate tends to be between 310°C and 370°C, it is preferable that the alumina source that can be included in the raw material composition is one or more selected from the group consisting of sodium aluminate, aluminum hydroxide, aluminum sulfate, and crystalline aluminosilicate, and more preferably sodium aluminate.

[0064] Furthermore, if other starting materials in the raw material composition besides the alumina source contain aluminum, these can be considered as alumina sources. For example, if the silica source is a substance containing aluminum, such as crystalline aluminosilicate, then the silica source can be considered both a silica source and an alumina source.

[0065] The iron source included in the raw material composition is an iron-containing compound, such as one or more selected from the group consisting of iron nitrate, iron chloride, iron sulfate, and metallic iron. It is preferable that the iron source included in the raw material composition is iron(III) nitrate, as this makes it easier for the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate to be between 310°C and 370°C.

[0066] The hexamethonium source contained in the raw material composition is hexamethonium (C) in the raw material composition. １２ H ３０ [N ＋ ] ２ The substance is capable of producing ), and examples include hexamethonium or a salt thereof. Since the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the produced ZSM-48 metallosilicate tends to be between 310°C and 370°C, the hexamethonium source included in the raw material composition is preferably one or more selected from the group consisting of hexamethonium hydroxide, hexamethonium bromide, hexamethonium chloride, and hexamethonium iodide, more preferably at least one of hexamethonium chloride, hexamethonium hydroxide, and hexamethonium bromide, and even more preferably at least one of hexamethonium chloride and hexamethonium hydroxide (hexamethonium dihydroxyl). The hexamethonium functions as an SDA directed towards ZSM-48 zeolite (ZSM-48 metallosilicate).

[0067] The alkali source included in the raw material composition may be any compound containing an alkali metal element, for example, at least one of alkali metal hydroxides and halides. The alkali metal element included in the alkali source is preferably one or more selected from the group of lithium, sodium, potassium, rubidium, and cesium, more preferably at least one of sodium and potassium, and even more preferably sodium, in order to facilitate the production of the ZSM-48 metallosilicate of this embodiment, which is more suitable as a catalyst substrate.

[0068] The water contained in the raw material composition may be one or more selected from the group consisting of distilled water, deionized water, and pure water. The water contained in the raw material composition may also originate from other starting materials contained in the raw material composition, such as solvents or aqueous compounds.

[0069] The raw material composition may consist only of amorphous aluminosilicate, an iron source, a hexamethonium source, an alkali source, and water, but other substances may be included in addition to these. Examples of such other substances include silica sources and alumina sources other than amorphous aluminosilicate, and SDAs other than hexamethonium and / or salts thereof that are directed toward ZSM-48 zeolites (ZSM-48 metallosilicates) (hereinafter referred to as "other SDA sources"). Examples of other SDA sources include one or more amines selected from the group consisting of ethylenediamine, n-butylamine, di-n-butylamine, n-propylamine, di-n-propylamine, dipropylenetriamine, triethylenetetramine, diethylenetriamine, ethanolamine, and propanolamine, tetramethylammonium, glycerol, alcohols, and morpholin, and one or more of these may be used.

[0070] The composition of the raw material is not particularly limited as long as it can produce the ZSM-48 metallosilicate of this embodiment, but the peak top position of the H peak (H peak in the ammonia temperature-induced desorption spectrum) of the ZSM-48 metallosilicate produced by the manufacturing method of this embodiment is such that the raw material composition contains SiO２ / Al ２ O ３ Molar ratio, Fe / Al molar ratio, silica (SiO ２ ) The molar ratio of alkali metals to silicon (hereinafter referred to as "M / SiO") ２ Also called the molar ratio, and the molar ratio of water to silica (hereinafter referred to as "H") ２ O / SiO ２ It is susceptible to the influence of the molar ratio, and the average grain size and aspect ratio of the ZSM-48 metallosilicate produced by the manufacturing method of this embodiment are influenced by silica (SiO2) in the raw material composition. ２ ) The molar ratio of SDA to silicon (hereinafter referred to as "SDA / SiO") ２ Also called "molar ratio"), H ２ O / SiO ２ Molar ratio, and silica (SiO ２ ) The molar ratio of hydroxide ions to silicon (hereinafter referred to as "OH / SiO") ２ It is susceptible to the influence of the molar ratio (also called the molar ratio). For this reason, the SiO in the raw material composition ２ / Al ２ O ３ Molar ratio, Fe / Al molar ratio, SDA / SiO ２ Molar ratio, M / SiO ２ Molar ratio, OH / SiO ２ Mole ratio, and H ２ O / SiO ２ The molar ratio is preferably adjusted so that the peak top position of the H peak of the manufactured ZSM-48 metallosilicate is between 310°C and 370°C, and the average crystal grain size of the manufactured ZSM-48 metallosilicate is 0.1 μm or less. A raw material composition that tends to result in the peak top position of the H peak of the manufactured ZSM-48 metallosilicate being between 310°C and 370°C, and the average crystal grain size of the manufactured ZSM-48 metallosilicate being 0.1 μm or less, is, for example, as follows.

[0071] SiO in raw material composition ２ / Al ２ O ３The molar ratio is preferably 50 or more, 80 or more, or 110 or more, and preferably 10,000 or less, 5,000 or less, or 4,000 or less. ２ / Al ２ O ３ The combination of the upper and lower limits of the molar ratio is arbitrary, but it is preferably 50 to 10,000, more preferably 80 to 5,000, and even more preferably 110 to 4,000.

[0072] The Fe / Al molar ratio in the raw material composition is preferably 0.05 or higher, 0.10 or higher, or 0.15 or higher, and preferably 100 or lower, 75 or lower, or 50 or lower. The combination of the upper and lower limits of the Fe / Al molar ratio described above is arbitrary, but it is preferably 0.05 or higher and 100 or lower, more preferably 0.10 or higher and 75 or lower, and even more preferably 0.15 or higher and 50 or lower.

[0073] SDA / SiO in raw material composition ２ The molar ratio is preferably 0.01 or higher, 0.014 or higher, or 0.018 or higher, and preferably 0.03 or lower, 0.025 or lower, or 0.022 or lower. ２ The combination of the upper and lower limits of the molar ratio is arbitrary, but it is preferably 0.01 or more and 0.03 or less, more preferably 0.014 or more and 0.025 or less, and even more preferably 0.018 or more and 0.022 or less.

[0074] M / SiO in raw material composition ２ The molar ratio is preferably 0.02 or higher, 0.04 or higher, or 0.08 or higher, and preferably 0.50 or lower, 0.40 or lower, or 0.30 or lower. ２ The combination of the upper and lower limits of the molar ratio is arbitrary, but it is preferably 0.02 or more and 0.50 or less, more preferably 0.04 or more and 0.40 or less, and even more preferably 0.08 or more and 0.30 or less. ２In the molar ratio, M is the total amount of alkali metals, and when the alkali metal is sodium, or when the alkali metal is sodium and potassium, it is M / SiO ２ The molar ratios are Na / SiO ２ Molar ratio, or (Na + K) / SiO ２ This will be the molar ratio.

[0075] OH / SiO in raw material compositions ２ The molar ratio is preferably 0.05 or higher, 0.10 or higher, or 0.14 or higher, and preferably 0.50 or lower, 0.40 or lower, or 0.30 or lower. ２ The combination of the upper and lower limits of the molar ratio is arbitrary, but it is preferably 0.05 or more and 0.50 or less, more preferably 0.10 or more and 0.40 or less, and even more preferably 0.14 or more and 0.30 or less. Note that when a hexamethonium halide is used as the hexamethonium source, halogens derived from the hexamethonium source may combine with hydroxide ions. Therefore, when a hexamethonium halide is used as the hexamethonium source, the OH / SiO ratio in the raw material composition is more favorable compared to when hexamethonium other than halides is used. ２ It is preferable to increase the molar ratio.

[0076] H in the raw material composition ２ O / SiO ２ The molar ratio is preferably 5 or more, 8 or more, or 10 or more, and preferably 25 or less, 22 or less, or 18 or less. ２ O / SiO ２ The combination of the upper and lower limits of the molar ratio is arbitrary, but H ２ O / SiO ２ The molar ratio is preferably 5 to 25, more preferably 8 to 22, and even more preferably 10 to 18.

[0077] Furthermore, SiO in the raw material composition ２ / (Al ２ O ３ +Fe ２ O ３The molar ratio is preferably 30 or more, 40 or more, or 50 or more, and preferably 300 or less, 200 or less, or 120 or less, in order to facilitate the production of the ZSM-48 metallosilicate of this embodiment, which is more suitable as a catalyst substrate. ２ / (Al ２ O ３ +Fe ２ O ３ ) The combination of the upper and lower limits of the molar ratio is arbitrary, but it is preferable that it be 30 to 300, more preferably 40 to 200, and even more preferably 50 to 120, in order to facilitate the production of the ZSM-48 metallosilicate of this embodiment which is more suitable as a catalyst substrate.

[0078] In the method for producing the ZSM-48 metallosilicate of this embodiment, the raw material composition preferably has the following molar composition, as this facilitates the production of the ZSM-48 metallosilicate of this embodiment: SiO ２ / Al ２ O ３ Molar ratio = 50 to 10000, or more preferably 110 to 4000 Fe / Al molar ratio = 0.05 to 100, or more preferably 0.15 to 50 SiO ２ / (Al ２ O ３ +Fe ２ O ３ ) Molar ratio = 30 or more and 300 or less, or more preferably 50 or more and 120 or less SDA / SiO ２ Molar ratio = 0.01 or more and 0.03 or less, or more preferably 0.018 or more and 0.022 or less M / SiO ２ Molar ratio = 0.02 or more and 0.50 or less, or more preferably 0.08 or more and 0.30 or less OH / SiO ２ Molar ratio = 0.05 or more and 0.50 or less, or more preferably 0.14 or more and 0.30 or less H ２ O / SiO ２Mole ratio = 5 to 25, or more preferably 10 to 18.

[0079] In the crystallization process, the raw material composition is crystallized in the presence of a seed crystal. By crystallizing the raw material composition in the presence of a seed crystal, a single-phase ZSM-48 zeolite (ZSM-48 metallosilicate) can be produced. A specific example of a single-phase ZSM-48 zeolite is a single-phase ZSM-48 zeolite that does not contain amorphous material. As a method for crystallizing the raw material composition in the presence of a seed crystal, one example is to crystallize a mixture obtained by mixing the raw material composition and a seed crystal.

[0080] The amount of seed crystal used in the crystallization process can be appropriately set within the range in which the ZSM-48 metallosilicate of this embodiment can be produced. To make the ZSM-48 metallosilicate of this embodiment easier to produce, the silicon in the raw material composition (without seed crystal) is converted to silica (SiO₂). ２ The mass ratio of silicon in the seed crystal converted to silica relative to the mass converted to (100 mass%) (hereinafter also referred to as "seed crystal amount") is preferably greater than 0 mass%, 0.1 mass% or more, or 0.5 mass% or more, and preferably 20 mass% or less, 10 mass% or less, or 5 mass% or less. The combination of the upper and lower limits of the seed crystal amount described above is arbitrary, but in order to make the ZSM-48 metallosilicate of this embodiment easier to manufacture, it is preferably greater than 0 mass% and 20 mass% or less, more preferably 0.1 mass% or less and 10 mass% or less, and even more preferably 0.5 mass% or more and 5 mass% or less.

[0081] The seed crystal used in the crystallization process only needs to contain a zeolite having a microstructure (composite building unit (CBU)) in its skeletal structure that is common to ZSM-48 zeolites. For example, one or more zeolites selected from the group consisting of ZSM-48 zeolites, AFI type zeolites, MFI type zeolites, MEL type zeolites, MWW type zeolites, YFI type zeolites, IMF type zeolites, and CON type zeolites can be used. To facilitate the production of the ZSM-48 metallosilicate of this embodiment, the seed crystal preferably contains one or more zeolites selected from the group consisting of ZSM-48 zeolites, MFI type zeolites, MEL type zeolites, and MWW type zeolites, and more preferably contains ZSM-48 zeolites. The seed crystal used in the crystallization process may consist solely of zeolites having a microstructure common to ZSM-48 zeolites, or it may be a mixture of such zeolites and amorphous materials. Commercially available seed crystals may be used, or those manufactured by known methods may be used.

[0082] In the crystallization process, the raw material composition is crystallized in the presence of seed crystals. Crystallization of the raw material composition can be carried out by hydrothermal treatment of the raw material composition in the presence of seed crystals. Hydrothermal treatment can be performed by placing the raw material composition and seed crystals in a sealed pressure-resistant container and heating it. Examples of hydrothermal treatment conditions include the following. Note that the average crystal grain size and aspect ratio of the manufactured ZSM-48 metallosilicate are easily affected by the treatment temperature of the hydrothermal treatment. Since the average crystal grain size of the manufactured ZSM-48 metallosilicate tends to be 0.1 μm or less, the hydrothermal treatment temperature is preferably 140°C to 170°C, and more preferably 140°C to 160°C. Treatment temperature: 80°C or higher or 140°C or higher, and 170°C or lower or 160°C or lower Treatment time: 2 hours to 500 hours or less Treatment pressure: Self-crystallization pressure

[0083] The method for producing the ZSM-48 metallosilicate of this embodiment may include a post-treatment step after the crystallization step, in addition to the crystallization step described above. Examples of post-treatment steps include one or more steps selected from the group consisting of a washing step, a drying step, an SDA removal step, and an ion exchange step. These post-treatment steps can be performed in any order, and the same step may be performed two or more times.

[0084] In the washing process, the ZSM-48 metallosilicate is washed. The washing method is arbitrary, but one example is to bring the ZSM-48 metallosilicate into contact with a sufficient amount of pure water.

[0085] In the drying process, the ZSM-48 metallosilicate is dried. The drying method is arbitrary, but one example is drying by heating. The drying conditions are also arbitrary, but one example is treating the ZSM-48 metallosilicate in air at a temperature of 100°C to 150°C for 2 to 24 hours.

[0086] In the SDA removal process, SDA is removed from the ZSM-48 metallosilicate. In the SDA removal process, all of the SDA contained in the ZSM-48 metallosilicate may be removed, or only some of the SDA may be removed. The removal of SDA can be carried out by conventionally known methods and is not particularly limited, but for example, calcination treatment can be used. The calcination conditions are arbitrary, but for example, conditions of calcination in air at 450°C to 700°C for 1 to 4 hours can be used.

[0087] The ion exchange process is a process of converting ZSM-48 group metallosilicates to any desired cation type. For example, the cation type of ZSM-48 group metallosilicate can be converted to the ammonium type (hereinafter referred to as "NH ４ ＋To make it a "proton type" (H), a treatment can be used in which an aqueous solution containing ammonium ions (hereinafter also referred to as "ammonium aqueous solution") is brought into contact with a ZSM-48 metallosilicate. For example, an aqueous solution of ammonium chloride can be used as the aqueous ammonium solution used in the ion exchange treatment. The contact conditions between the aqueous ammonium solution and the ZSM-48 metallosilicate, and the ammonia concentration of the aqueous ammonium solution should be set appropriately considering the ion exchange rate. In addition, the cation type of the ZSM-48 metallosilicate can be set to the proton type (H). ＋ To make it a type, for example, NH ４ ＋ A treatment can be used in which a ZSM-48 type metallosilicate is calcined in air at a temperature of 500°C to 600°C for 1 to 10 hours.

[0088] The ZSM-48 metallosilicate of this embodiment described above can be used as a base material for a catalyst for isomerization reactions to isomerize straight-chain paraffins into branched paraffins, or as a base material for a catalyst for MTO reactions to produce olefins from methanol. Straight-chain paraffins are hydrocarbons of paraffin with a straight-chain molecular structure, while branched paraffins are hydrocarbons of paraffin with a molecular structure in which the carbon chain has side chains. Straight-chain paraffins are sometimes called normal paraffins. The base material is the material that forms the basis of the catalyst, and may be used as a catalyst on its own, or as a carrier for supporting a predetermined component.

[0089] The following describes the isomerization reaction catalyst (hereinafter also referred to as "the isomerization reaction catalyst according to this embodiment") that uses the ZSM-48 metallosilicate of this embodiment as a base material.

[0090] The isomerization catalyst according to this embodiment includes the ZSM-48 metallosilicate of this embodiment as a base material. In other words, the isomerization catalyst according to this embodiment may consist only of the ZSM-48 metallosilicate of this embodiment, or it may contain, in addition to the ZSM-48 metallosilicate of this embodiment, a predetermined component supported on the ZSM-48 metallosilicate of this embodiment. From the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, it is preferable that the isomerization catalyst according to this embodiment contains, in addition to the ZSM-48 metallosilicate of this embodiment, a predetermined component supported on the ZSM-48 metallosilicate of this embodiment.

[0091] In the isomerization reaction catalyst according to this embodiment, the predetermined component that can be supported on the ZSM-48 metallosilicate of this embodiment is preferably a metallic element from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature. Examples of metallic elements that can be supported on the ZSM-48 metallosilicate of this embodiment include one or more metallic elements selected from the group consisting of platinum, nickel, cobalt, ruthenium, iridium, molybdenum, tungsten, and palladium, with platinum being more preferable. The state of the metallic element that can be supported on the ZSM-48 metallosilicate of this embodiment is not particularly limited and may be a compound (e.g., oxide), ion, complex, or elemental (metal), with metal being preferable. Note that the ZSM-48 metallosilicate of this embodiment may have multiple metallic elements in different states supported on it.

[0092] The content of metal elements can be set appropriately within the range in which the isomerization reaction proceeds, and is not particularly limited. However, from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, it is preferable that the content be 0% by mass or more, 0.01% by mass or more, or 0.05% by mass or more, and preferably 30% by mass or less, 25% by mass or less, 20% by mass or less, 10% by mass or less, or 1% by mass or less, per 100 mass of the isomerization reaction catalyst. The combination of the upper and lower limits of the metal element content described above is arbitrary, but from the viewpoint of further promoting the isomerization reaction, it is preferable that the content of metal elements be 0% by mass or more and 30% by mass or less, more preferably 0.01% by mass or more and 25% by mass or less, even more preferably 0.05% by mass or more and 20% by mass or less, particularly preferably 0.05% by mass or more and 10% by mass or less, and most preferably 0.05% by mass or more and 1% by mass or less. Note that the content of metal elements refers to the content assuming that all supported metal elements are in the state of metal (elemental form). Furthermore, a content of 0% by mass means that the component is substantially absent, and substantially absent means that the component is not detectable (below the detection limit).

[0093] The method for supporting the metal element on the ZSM-48 metallosilicate of this embodiment is not particularly limited, and conventionally known methods can be used. For example, an aqueous solution containing the metal element (hereinafter also referred to as "metal aqueous solution") can be impregnated into the ZSM-48 metallosilicate of this embodiment and then dried.

[0094] The aqueous metal solution impregnated into the ZSM-48 metallosilicate in this embodiment is an aqueous solution of a metal salt dissolved in water. Examples of metal salts contained in the aqueous metal solution include one or more selected from the group consisting of hexachloride platinum(IV) acid, chloride, sulfate, and nitrate, and it is preferable that it is at least one of hexachloride platinum(IV) acid and nitrate, with hexachloride platinum(IV) acid being more preferable. The concentration of the metal element in the aqueous metal solution is not particularly limited and can be set appropriately considering the content of the metal element in the catalyst for the isomerization reaction.

[0095] To impregnate the ZSM-48 metallosilicate of this embodiment with an aqueous metal solution, a contact treatment can be used in which the ZSM-48 metallosilicate of this embodiment is brought into contact with the aqueous metal solution. The contact conditions are not particularly limited and can be set appropriately considering the content of the metal element in the catalyst for the isomerization reaction.

[0096] The drying of the ZSM-48 metallosilicate of this embodiment, which has been impregnated with a metal aqueous solution, can be any method that can remove water from the ZSM-48 metallosilicate of this embodiment, and is not particularly limited, but for example, conditions such as heating in air at a temperature of 60°C to 180°C for 0.1 hours to 10 hours can be given.

[0097] By drying the ZSM-48 metallosilicate of this embodiment, which has been impregnated with a metal aqueous solution, the metal element can be supported on the ZSM-48 metallosilicate of this embodiment. The ZSM-48 metallosilicate of this embodiment, on which the metal element is supported, may be used as is as a catalyst for the isomerization reaction according to this embodiment, but it is preferable to perform a calcination treatment before using it as a catalyst for the isomerization reaction according to this embodiment. By performing the calcination treatment, the detachment of the metal element can be suppressed. The calcination conditions are not particularly limited, but conditions such as calcination in air at a temperature of 300°C to 600°C for 0.5 hours to 10 hours can be mentioned.

[0098] The isomerization reaction of linear paraffins using the isomerization catalyst according to this embodiment can be carried out by contacting the isomerization catalyst according to this embodiment with a fluid containing linear paraffins and hydrogen (hereinafter also referred to as "linear paraffin-containing fluid"). When the isomerization catalyst according to this embodiment comes into contact with the linear paraffin-containing fluid, the linear paraffins in the linear paraffin-containing fluid are isomerized to produce branched paraffins.

[0099] The method of contacting the isomerization catalyst and the linear paraffin-containing fluid according to this embodiment is not particularly limited, but examples include a method in which the isomerization catalyst according to this embodiment is packed into a fixed-bed flow-type reaction tube and the linear paraffin-containing fluid is flowed through it (flow method), or a method in which the inside of a reaction vessel containing the isomerization catalyst according to this embodiment is filled with the linear paraffin-containing fluid (batch reaction method).

[0100] The linear paraffin-containing fluid brought into contact with the isomerization catalyst according to this embodiment contains at least linear paraffin and hydrogen. Examples of linear paraffin contained in the linear paraffin-containing fluid include linear paraffin having 4 to 100 carbon atoms. From the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, the linear paraffin contained in the linear paraffin-containing fluid is preferably linear paraffin having 5 to 80 carbon atoms, more preferably linear paraffin having 7 to 50 carbon atoms, even more preferably linear paraffin having 9 to 20 carbon atoms, and particularly preferably n-decane (n-decane).

[0101] The linear paraffin-containing fluid brought into contact with the isomerization catalyst according to this embodiment may consist only of linear paraffin and hydrogen, or it may further contain components other than linear paraffin and hydrogen. However, from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, it is preferable that the fluid consists only of linear paraffin and hydrogen.

[0102] The linear paraffin-containing fluid brought into contact with the isomerization catalyst according to this embodiment may be a liquid, a gas, or a mixture of liquid and gas.

[0103] The contact conditions between the isomerization catalyst and the linear paraffin-containing fluid according to this embodiment can be adjusted as appropriate within the range in which the isomerization reaction of the linear paraffin proceeds, but preferred contact conditions include the following.

[0104] The contact temperature between the isomerization reaction catalyst and the linear paraffin-containing fluid according to this embodiment is not particularly limited, but from the viewpoint of further improving the branched paraffin yield, it is preferably 200°C or higher, 220°C or higher, or 240°C or higher, and preferably 400°C or lower, 360°C or lower, or 320°C or lower. The combination of the upper and lower limits of the contact temperature described above is arbitrary, but from the viewpoint of further improving the branched paraffin yield, it is preferably 200°C or higher and 400°C or lower, more preferably 220°C or higher and 360°C or lower, and even more preferably 240°C or higher and 320°C or lower.

[0105] The pressure (gauge pressure) of the atmosphere into which the isomerization reaction catalyst and the linear paraffin-containing fluid are brought into contact according to this embodiment is not particularly limited, but from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, it is preferably 0 MPaG or higher, 0.05 MPaG or higher, or 0.1 MPaG or higher, and preferably 10 MPaG or lower, 5 MPaG or lower, or 3 MPaG or lower. The combination of the upper and lower limits of the contact atmosphere pressure (gauge pressure) described above is arbitrary, but from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, the pressure (gauge pressure) of the contact atmosphere is preferably 0 MPaG or higher and 10 MPaG or lower, more preferably 0.05 MPaG or higher and 5 MPaG or lower, and even more preferably 0.1 MPaG or higher and 3 MPaG or lower. Note that gauge pressure is the pressure with atmospheric pressure set to 0 MPaG.

[0106] From the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, the weight space velocity (WHSV) of the linear paraffin in the linear paraffin-containing fluid that comes into contact with the isomerization reaction catalyst according to this embodiment is 0.5 h. －１ Total: 1.0h －１ or more, or 1.5 hours －１ Preferably, it is 10h －１ Below, 5 hours －１ The following, or 2.5 hours －１ The following is preferable. The combination of the upper and lower limits of the WHSV of the linear paraffin mentioned above is arbitrary, but from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, 0.5 h－１ 10 hours or more －１ Preferably, it is 1.0h －１ More than 5 hours －１ It is more preferable that the following conditions are met: 1.5h －１ 2.5 hours or more －１ The following is even more preferable. Note that the WHSV of linear paraffin is a parameter that represents the amount of linear paraffin supplied per hour per unit mass of isomerization catalyst ([g (isomerization catalyst)] / [g (linear paraffin) / h] = [h －１ )]))

[0107] The volume ratio of hydrogen to linear paraffin in the linear paraffin-containing fluid that comes into contact with the isomerization catalyst according to this embodiment (hereinafter also referred to as the "hydrogen / linear paraffin volume ratio") is preferably 200 or more, 400 or more, or 500 or more, and preferably 2000 or less, 1500 or less, or 1200 or less, from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature. The combination of the upper and lower limits of the hydrogen / linear paraffin volume ratio described above is arbitrary, but from the viewpoint of further improving the branched paraffin yield at the optimal reaction temperature, it is preferably 200 or more and 2000 or less, more preferably 400 or more and 1500 or less, and even more preferably 500 or more and 1200 or less.

[0108] The contact time between the isomerization reaction catalyst and the linear paraffin-containing fluid according to this embodiment may be set appropriately according to the amount of branched paraffin to be produced.

[0109] By contacting the isomerization catalyst according to this embodiment with a linear paraffin-containing fluid, the linear paraffin is isomerized, yielding a branched paraffin (a branched paraffin with the same composition as the linear paraffin atoms used as the raw material) in which the arrangement of linear paraffin atoms has changed. The resulting branched paraffin varies depending on the linear paraffin used as the raw material, but for example, when n-decane is used as the linear paraffin, 4-methylnonane is produced as the branched paraffin.

[0110] Next, we will describe the MTO reaction catalyst (hereinafter also referred to as "the MTO reaction catalyst according to this embodiment") that uses the ZSM-48 group metallosilicate of this embodiment as a base material.

[0111] The MTO reaction catalyst according to this embodiment includes the ZSM-48 metallosilicate of this embodiment as a substrate. In other words, the MTO reaction catalyst according to this embodiment may consist only of the ZSM-48 metallosilicate of this embodiment, or it may contain, in addition to the ZSM-48 metallosilicate of this embodiment, a predetermined component supported on the ZSM-48 metallosilicate of this embodiment. In the MTO reaction catalyst according to this embodiment, the predetermined component that can be supported on the ZSM-48 metallosilicate of this embodiment is not particularly limited as long as it does not inhibit the reaction that produces olefins from methanol (hereinafter also referred to as the "MTO reaction").

[0112] The MTO reaction using the MTO reaction catalyst according to this embodiment can be carried out by contacting the MTO reaction catalyst according to this embodiment with a methanol-containing fluid (hereinafter also referred to as "methanol-containing fluid"). When the MTO reaction catalyst according to this embodiment comes into contact with the methanol-containing fluid, olefins are produced from methanol.

[0113] The method of contacting the MTO reaction catalyst with the methanol-containing fluid in this embodiment is not particularly limited, but examples include filling a fixed-bed flow-through reaction tube with the MTO reaction catalyst according to this embodiment and flowing the methanol-containing fluid through it (flow method), or filling the inside of a reaction vessel containing the MTO reaction catalyst according to this embodiment with the methanol-containing fluid (batch reaction method).

[0114] The methanol-containing fluid brought into contact with the MTO reaction catalyst according to this embodiment may consist solely of methanol, but may also contain other components in addition to methanol. Examples of such other components include one or more selected from the group consisting of nitrogen, helium, and argon, with nitrogen being preferred.

[0115] The methanol-containing fluid brought into contact with the MTO reaction catalyst according to this embodiment may be a liquid, a gas, or a mixture of liquid and gas; however, from the viewpoint of further improving the selectivity of the C4 branched olefin, it is preferably a gas.

[0116] The contact conditions between the MTO reaction catalyst and the methanol-containing fluid according to this embodiment can be adjusted as appropriate within the range in which the MTO reaction proceeds, but preferred contact conditions include the following.

[0117] From the viewpoint of further improving the selectivity of C4 branched olefins, the contact temperature between the MTO reaction catalyst and the methanol-containing fluid according to this embodiment is preferably 260°C or higher, 300°C or higher, or 320°C or higher, and preferably 450°C or lower, 400°C or lower, or 360°C or lower. The combination of the upper and lower limits of the contact temperature described above is arbitrary, but from the viewpoint of further improving the selectivity of C4 branched olefins, it is preferably 260°C or higher and 450°C or lower, more preferably 300°C or higher and 400°C or lower, and even more preferably 320°C or higher and 360°C or lower.

[0118] The pressure (gauge pressure) of the atmosphere into which the MTO reaction catalyst and methanol-containing fluid are brought into contact according to this embodiment is not particularly limited, but from the viewpoint of further improving the selectivity of C4 branched olefins, it is preferably 0 MPaG or higher, 0.05 MPaG or higher, or 0.1 MPaG or higher, and preferably 5 MPaG or lower, 2 MPaG or lower, or 1 MPaG or lower. The combination of the upper and lower limits of the contact atmosphere pressure (gauge pressure) described above is arbitrary, but from the viewpoint of further improving the selectivity of C4 branched olefins, the pressure (gauge pressure) of the contact atmosphere is preferably 0 MPaG or higher and 5 MPaG or lower, more preferably 0.05 MPaG or higher and 2 MPaG or lower, and even more preferably 0.1 MPaG or higher and 1 MPaG or lower. Note that gauge pressure is the pressure with atmospheric pressure set to 0 MPaG.

[0119] The weight space velocity (WHSV) of methanol in the methanol-containing fluid contacted with the MTO reaction catalyst according to this embodiment is not particularly limited, but from the viewpoint of further improving the selectivity of C4 branched olefins, it is 0.3h. －１ More than 0.5h －１ or more, or 1 hour －１ Preferably, it is 10h －１ Below, 8 hours －１ The following, or 5 hours －１ The following is preferable. The combination of the upper and lower limits of methanol WHSV mentioned above is arbitrary, but from the viewpoint of further improving the selectivity of C4 branched olefins, 0.3h －１ 10 hours or more －１ Preferably, it is 0.5h －１ More than 8 hours －１ More preferably, 1h －１ More than 5 hours －１ The following is even more preferable. Note that the WHSV of methanol is a parameter that represents the amount of methanol supplied per hour per unit mass of the MTO reaction catalyst ([g(MTO reaction catalyst)] / [g(methanol) / h] = [h －１ )]))

[0120] The contact time between the MTO reaction catalyst and the methanol-containing fluid according to this embodiment may be set appropriately according to the amount of olefin to be produced.

[0121] By contacting the MTO reaction catalyst according to this embodiment with a methanol-containing fluid, an olefin is produced from methanol. The produced olefin is preferably a C4 branched olefin because it is easily usable as a raw material for various chemicals. Specific examples of C4 branched olefins include raw materials for the synthesis of liquid fuels, synthetic resins, and various plastics. The substance produced by contacting the MTO reaction catalyst according to this embodiment with a methanol-containing fluid is not limited to a C4 branched olefin, and one or more substances selected from the group consisting of olefins other than C4 branched olefins, paraffins, and aromatic hydrocarbons may be produced as well.

[0122] Next, examples of this embodiment are shown. However, this embodiment is not limited to these examples.

[0123] (Powder X-ray Diffraction) The XRD of the sample was measured using a general-purpose X-ray diffractometer (instrument name: Ultima IV Protectus, manufactured by Rigaku). The measurement conditions were as follows: Acceleration current / voltage: 40 mA / 40 kV Radiation source: CuKα rays (λ = 1.5405 Å) Measurement mode: Continuous scan Scanning conditions: 40° / min Measurement range: 2θ = 3° to 43° Divergence longitudinal limiting slit: 10 mm Divergence / entry slit: 1° Receiving slit: open Receiving solar slit: 5° Detector: Semiconductor detector (D / teX Ultra) Filter: Ni filter

[0124] The XRD patterns obtained from sample measurements were analyzed using general analysis software (SmartLab Studio II, Rigaku) ​​under the following conditions to identify the XRD peaks. Furthermore, the skeletal structure of the sample was identified by comparing the XRD patterns with a reference pattern. Fitting conditions: Automatic, background refined, dispersed pseudo-Voigt function (peak shape) Background removal method: Fitting method Kα2 removal method: Kα1 / Kα2 ratio = 0.497 Smoothing method: B-Spline curve Smoothing conditions: Second derivative method, σ cut value = 3, χ threshold = 1.5

[0125] (Compositional analysis, quantitative determination of silicon, aluminum, iron, gallium, titanium, and sodium) The compositional analysis of the sample was performed using a general inductively coupled plasma atomic emission spectrometer (instrument name: OPTIMA3300DV, manufactured by PERKIN ELMER). The sample was dissolved in a mixed solution of hydrofluoric acid and nitric acid in air to prepare the measurement solution. The obtained measurement solution was put into the instrument to analyze the composition of the sample, and each component was quantified using the calibration curve method. The calibration curve was created by measuring the intensity of the emission peak corresponding to the component for standard solutions whose component amounts are known, and drawing a line (calibration curve) showing the relationship between the intensity and the component amount. From the obtained molar concentrations of silicon (Si), aluminum (Al), iron (Fe), gallium (Ga), titanium (Ti), and sodium (Na), SiO2 was calculated. ２ / Al ２ O ３ Molar ratio, SiO ２ / (Al ２ O ３ +Fe ２ O ３ ) Molar ratio, alumina (Al ２ O ３ ) Aluminum and gallium(III) oxide (Ga ２ O ３ Silica (SiO₂) relative to the total number of moles of gallium (converted to ) ２ ) Ratio of the number of moles of silicon converted to (hereinafter referred to as "SiO ２ / (Al ２ O ３ +Ga ２ O ３ (Also called "molar ratio"), titania (TiO ２ Silica (SiO) relative to titanium (calculated as equivalent) ２ ) Molar ratio of silicon (hereinafter referred to as "SiO ２ / TiO ２ Also called "molar ratio"), alumina (Al ２ O ３ ) Aluminum and titania (TiO) ２ Silica (SiO) relative to the total number of moles of titanium (calculated as ) ２ ) Ratio of the number of moles of silicon converted to (hereinafter referred to as "SiO ２ / (Al ２ O ３ +TiO ２The Na / Al molar ratio and Fe / Al molar ratio (also called the molar ratio) were calculated.

[0126] (Measurement of average crystal grain size) The sample was observed using a general scanning electron microscope (device name: JSM-IT200, manufactured by JEOL Ltd.) under the following conditions. 100 ± 10 primary particles whose contours were observed without interruption in the obtained SEM observation image were arbitrarily selected. For each selected primary particle, the distance between the two parallel lines tangent to the contour of the extracted primary particle was measured, and the average value of this distance was calculated and defined as the average crystal grain size. Acceleration voltage: 5 kV Magnification: 10,000 ± 5,000x

[0127] (Measurement of Aspect Ratio) Using the same method as for measuring the average grain size, 100 ± 10 primary particles were arbitrarily selected from those whose contours were observed without interruption in the SEM observation image. The longest diameter (the distance between the two parallel lines that are tangent to the contour of the primary particle when the primary particle is sandwiched between them) and the shortest diameter (the distance between the two parallel lines that are tangent to the contour of the primary particle when the primary particle is sandwiched between them when the shortest) were measured for each selected primary particle, and these were averaged to obtain the average longest diameter L1 [μm] and average shortest diameter L2 [μm]. The aspect ratio (L1 / L2) was obtained by substituting the average longest diameter L1 [μm] and average shortest diameter L2 [μm] into the above formula (1).

[0128] (Measurement of ammonia thermal desorption spectrum) The ammonia thermal desorption spectrum was measured using a general catalyst analyzer (instrument name: BELCAT II, ​​manufactured by Microtrac-Bel Co., Ltd.) ３- The measurement was performed using a method similar to the TPD method (Measurement of Solid Acid Properties by Ammonia Temperature Desorption Method, Catalysts, vol. 42, p. 218 (2000)). Specifically, first, 0.1 g of zeolite was pretreated by standing under a helium gas flow at 500°C for 1 hour, and this was used as the measurement sample. For the measurement sample after pretreatment, a mixed gas containing 10 vol% ammonia and 90 vol% helium was flowed through it at room temperature (25°C) for 1 hour to saturate the measurement sample with ammonia adsorption. The mixed gas was changed to helium gas, and the measurement sample with saturated ammonia adsorption was heated at 100°C for 1 hour to remove any remaining ammonia in the measurement atmosphere (ammonia not adsorbed on the measurement sample). After removing residual ammonia, the temperature was raised from 100°C to 600°C at a heating rate of 10°C / min under a helium flow rate of 50 mL / min. The amount of ammonia released from the zeolite during this heating process (released ammonia) was measured over time to obtain an ammonia heating desorption spectrum. Furthermore, for the H peaks (peaks with peak tops in the range above 300°C) included in the measured ammonia heating desorption spectrum, the temperature at which the peak top appears (the temperature at which the spectral intensity of the H peak reaches its maximum value) was identified.

[0129] (Measurement of B acid amount, L acid amount, and B acid / total acid) Infrared absorption spectra (IR spectra) were measured using an FT-IR spectrometer (instrument name: FT / IR-6X, manufactured by JASCO Corporation) with a heated transmission cell (manufactured by Makuhari Chemical Glass Works). The sample was press-molded into a cylindrical shape (8-12 mg, 1 cm in diameter) at a gauge pressure of 2.0 T, and measured at 1.0 × 10⁻⁶. －２ The sample was pretreated in a permeation cell at 450°C for 2 hours under a vacuum of less than Pa. Then, 1.0 × 10⁻⁶ －２ The sample was cooled to 150°C under vacuum conditions below Pa, and the background spectrum was measured under the following conditions: Sample area: 0.785 cm² ２ Measurement method: Heat transmission method Measurement temperature: 150°C Measurement wavelength range: 800-4000 cm⁻¹ Resolution: 2 cm⁻¹ Number of integrations: 128 Measurement atmosphere: Vacuum (1.0 × 10⁻¹) －２ Pa or less)

[0130] Next, pyridine was introduced into a heat permeation cell and brought into contact with the sample at 150°C for 20 minutes at 20 Pa. After that, a vacuum (1.0 × 10⁻⁶) was applied. －２ The heat permeation cell was treated at 150°C for 30 minutes under a pressure of Pa or less to remove excess pyridine, and then the adsorption spectrum was measured under the above measurement conditions. The background spectrum was subtracted from the obtained adsorption spectrum to obtain the difference spectrum.

[0131] In the obtained difference spectrum, 1450 ± 10 cm⁻¹ －１ The integrated intensity of the peak attributed to L-acid, which has a peak top at 1640 ± 10 cm², and 1640 ± 10 cm². －１ The integrated intensity of the peak attributed to acid B, which has a peak top at , was determined. The amount of acid B was determined by substituting the determined integrated intensity of the peak attributed to acid B into equation (2-A), and the amount of acid L was determined by substituting the determined integrated intensity of the peak attributed to acid L into equation (2-B). The amount of acid was determined by summing the determined amounts of acid B and acid L, and the amount of acid B / total acid was calculated from equation (3) using the amounts of acid B and acid L. Note that in equations (2-A) and (2-B), the area (S) of the measurement sample is used. ａｒｅａ ) includes the area of ​​the press-molded sample (i.e., 0.785 cm²). ２ Using ), the mass (S) of the sample to be measured ｍａｓｓ In equation (2-A) above, the mass [mg] of the sample after FT-IR measurement was used. Furthermore, in equation (2-B) above, 1.67 [cm / μmol] was used as the molar extinction coefficient of acid B, and in equation (2-B) above, 2.22 [cm / μmol] was used as the molar extinction coefficient of acid L.

[0132] Example 1 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ A raw material composition having the following molar composition was obtained by mixing iron(III) nitrate nonahydrate (ratio = 170), 25% by mass hexamethonium dihydroxyl (hereinafter also referred to as "HMDH") aqueous solution, 48% by mass sodium hydroxide, and water. SiO ２ / Al ２ O ３ Molar ratio = 170 Fe / Al molar ratio = 0.75 SiO２ / (Al ２ O ３ +Fe ２ O ３ ) Molar ratio = 97 HMDH / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.15 OH / SiO ２ Molar ratio = 0.19 H ２ O / SiO ２ Mole ratio = 11

[0133] As a seed crystal, SiO ２ / Al ２ O ３ A ZSM-48 zeolite with a ratio of 76 was prepared. The seed crystal (ZSM-48 aluminosilicate) was produced by adding the following amount of seed crystal (Beta-type crystalline aluminosilicate, Tosoh HSZ-930NHA) to a composition having the following molar composition, and then hydrothermally treating it at 160°C for 24 hours under autogenous pressure. The composition having the following molar composition is amorphous aluminosilicate (SiO ２ / Al ２ O ３ It was obtained by mixing hexamethonium hydroxide, 48% by mass of sodium hydroxide, and water (ratio = 85). SiO ２ / Al ２ O ３ Ratio = 85 HM(SDA) / SiO ２ Ratio = 0.02 Na(M) / SiO ２ Ratio = 0.11 OH / SiO ２ Ratio = 0.15H ２ O / SiO ２ Ratio = 10 Seed crystal amount = 1.5wt%

[0134] Seed crystals were mixed into the raw material composition to a seed crystal content of 1.5% by mass. The raw material composition was then filled into an 80 mL sealed container and sealed. The container was subjected to hydrothermal treatment at 160°C for 60 hours under self-stimulation pressure at a rotational speed of 55 rpm to obtain crystals. The obtained crystals were subjected to solid-liquid separation, washed with pure water, and dried overnight in the air at 110°C. The dried crystals were calcined in the air at 600°C for 2 hours. The calcined crystals were treated with a 20% ammonium chloride aqueous solution to perform ion exchange (NH₄). ４ ＋ Ion exchange was performed to form the desired shape. The ion-exchanged crystals were dried overnight in air at 110°C to obtain the ZSM-48 metallosilicate of this example.

[0135] The ZSM-48 metallosilicate of this embodiment had the XRD peaks shown in Table 4 below and did not contain any impurity phases other than ZSM-48. Furthermore, the ZSM-48 metallosilicate of this embodiment did not contain any peaks with a relative peak intensity exceeding 3%, other than the XRD peaks shown in Table 4 below. The ammonia temperature-induced desorption spectrum of the ZSM-48 metallosilicate of this embodiment is shown in Figure 1. The characteristics of the ZSM-48 metallosilicate of this embodiment are shown in Tables 8 and 9 below.

[0136] Example 2 The amorphous aluminosilicate from Example 1 is converted to SiO ２ / Al ２ O ３ The amorphous aluminosilicate with a ratio of 3938 was changed, and the amount of each raw material added was varied to obtain a raw material composition having the following molar composition. The ZSM-48 metallosilicate of this example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 3938 Fe / Al molar ratio = 38 SiO ２ / (Al ２ O ３ +Fe ２ O ３) Molar ratio = 10¹ HMDH / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.17 OH / SiO ２ Molar ratio = 0.21 H ２ O / SiO ２ Mole ratio = 11

[0137] The ZSM-48 metallosilicate of this embodiment had the XRD peaks shown in Table 5 below and did not contain any impurity phases other than ZSM-48. Furthermore, the ZSM-48 metallosilicate of this embodiment did not contain any peaks with a relative peak intensity exceeding 3%, other than the XRD peaks shown in Table 5 below. The ammonia temperature-induced desorption spectrum of the ZSM-48 metallosilicate of this embodiment is shown in Figure 2. The characteristics of the ZSM-48 metallosilicate of this embodiment are shown in Tables 8 and 9 below.

[0138] Example 3 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ Ratio = 3938), iron(III) nitrate notahydrate, 56% by mass aqueous solution of hexamethonium dichloride (hereinafter also referred to as "HMDC"), sodium aluminate (Na ２ O=19.1% by mass, Al ２ O ３ =19.6% by mass, H ２ O = 61.3% by mass, 48% by mass sodium hydroxide, and water were mixed to obtain a raw material composition having the following molar composition. The ZSM-48 metallosilicate of this example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 131 Fe / Al molar ratio = 0.75 SiO ２ / (Al ２ O ３ +Fe ２ O ３) Molar ratio = 75 HMDC / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.17 OH / SiO ２ Molar ratio = 0.17 H ２ O / SiO ２ Mole ratio = 11

[0139] The ZSM-48 metallosilicate of this embodiment had the XRD peaks shown in Table 6 below and did not contain any impurity phases other than ZSM-48. Furthermore, the ZSM-48 metallosilicate of this embodiment did not contain any peaks with a relative peak intensity exceeding 3%, other than the XRD peaks shown in Table 6 below. The ammonia temperature-controlled desorption spectrum of the ZSM-48 metallosilicate of this embodiment is shown in Figure 3. The characteristics of the ZSM-48 metallosilicate of this embodiment are shown in Tables 8 and 9 below.

[0140] Example 4 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ Ratio = 3938), iron(III) nitrate notahydrate, 56% by mass HMDC aqueous solution, sodium aluminate (Na ２ O=19.1% by mass, Al ２ O ３ =19.6% by mass, H ２ O = 61.3% by mass, 48% by mass sodium hydroxide, and water were mixed to obtain a raw material composition having the following molar composition. The ZSM-48 metallosilicate of this example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 110 Fe / Al molar ratio = 0.75 SiO ２ / (Al ２ O ３ +Fe ２ O ３ ) Molar ratio = 63 HMDC / SiO２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.19 OH / SiO ２ Molar ratio = 0.21 H ２ O / SiO ２ Mole ratio = 12

[0141] The ZSM-48 metallosilicate of this embodiment had the XRD peaks shown in Table 7 below and did not contain any impurity phases other than ZSM-48. Furthermore, the ZSM-48 metallosilicate of this embodiment did not contain any peaks with a relative peak intensity exceeding 3%, other than the XRD peaks shown in Table 7 below. The ammonia temperature-controlled desorption spectrum of the ZSM-48 metallosilicate of this embodiment is shown in Figure 4. The characteristics of the ZSM-48 metallosilicate of this embodiment are shown in Tables 8 and 9 below.

[0142] Comparative Example 1 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ A 25% by mass HMDH aqueous solution, 48% by mass sodium hydroxide, and water were mixed (ratio = 170) to obtain a raw material composition having the following molar composition. The ZSM-48 aluminosilicate of this comparative example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 170 HMDH / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.12 OH / SiO ２ Molar ratio = 0.16 H ２ O / SiO ２ Mole ratio = 11

[0143] The ZSM-48 aluminosilicate in this comparative example did not contain any impurity phases other than ZSM-48. The ammonia temperature-induced desorption spectrum of the ZSM-48 aluminosilicate in this comparative example is shown in Figure 5. The characteristics of the ZSM-48 aluminosilicate in this comparative example are shown in Tables 8 and 9 below.

[0144] Comparative Example 2: The amorphous aluminosilicate (SiO₂) used in Comparative Example 1. ２ / Al ２ O ３ Instead of the ratio = 170, amorphous aluminosilicate (SiO ２ / Al ２ O ３ Except for using a ratio of 95, the ZSM-48 aluminosilicate of this comparative example was obtained in the same manner as in Comparative Example 1. In this comparative example, the raw material composition had the following molar composition: SiO ２ / Al ２ O ３ Molar ratio = 95 HMDH / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.12 OH / SiO ２ Molar ratio = 0.16 H ２ O / SiO ２ Mole ratio = 11

[0145] The ZSM-48 aluminosilicate in this comparative example did not contain any impurity phases other than ZSM-48. The characteristics of the ZSM-48 aluminosilicate in this comparative example are shown in Tables 8 and 9 below.

[0146] Comparative Example 3 Amorphous aluminosilicate (SiO ２ / Al ２ O ３ A raw material composition having the following molar composition was obtained by mixing gallium nitrate n hydrate (ratio = 170), 25% by mass HMDH aqueous solution, 48% by mass sodium hydroxide, and water. The ZSM-48 metallosilicate of this comparative example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO２ / Al ２ O ３ Molar ratio = 170 Ga / Al molar ratio = 0.75 SiO ２ / (Al ２ O ３ +Ga ２ O ３ ) Molar ratio = 97 HMDH / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.17 OH / SiO ２ Molar ratio = 0.21 H ２ O / SiO ２ Mole ratio = 11

[0147] The ZSM-48 metallosilicate in this comparative example did not contain any impurity phases other than ZSM-48. The characteristics of the ZSM-48 metallosilicate in this comparative example are shown in Tables 8 and 9 below.

[0148] Comparative Example 4: Titanium-containing amorphous aluminosilicate (SiO ２ / Al ２ O ３ Ratio=3546, SiO ２ / TiO ２ A 25% by mass HMDH aqueous solution, 48% by mass sodium hydroxide, and water were mixed (ratio = 110) to obtain a raw material composition having the following molar composition. The ZSM-48 metallosilicate of this comparative example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 3546 SiO ２ / TiO ２ Molar ratio = 110 Ti / Al molar ratio = 16 SiO ２ / (Al ２ O ３ +TiO ２ ) Molar ratio = 100 HMDH / SiO ２Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.13 OH / SiO ２ Molar ratio = 0.17 H ２ O / SiO ２ Mole ratio = 11

[0149] The ZSM-48 metallosilicate in this comparative example did not contain any impurity phases other than ZSM-48. The characteristics of the ZSM-48 metallosilicate in this comparative example are shown in Tables 8 and 9 below.

[0150] Comparative Example 5: Colloidal silica (LUDOX® HS-40), sodium aluminate aqueous solution (Al ２ O ３ = 7.2 wt%, N ２ A raw material composition having the following molar composition was obtained by mixing 7.4 wt% O, iron(II) sulfate heptahydrate, 56% by mass HMDC aqueous solution, 48% by mass sodium hydroxide, and water. The ZSM-48 metallosilicate of this comparative example was obtained in the same manner as in Example 1, except that the obtained raw material composition was used instead of the raw material composition used in Example 1. SiO ２ / Al ２ O ３ Molar ratio = 170 Fe / Al molar ratio = 0.75 SiO ２ / (Al ２ O ３ +Fe ２ O ３ ) Molar ratio = 97 HMDC / SiO ２ Molar ratio = 0.02 Na / SiO ２ Molar ratio = 0.15 OH / SiO ２ Molar ratio = 0.19 H ２ O / SiO ２ Mole ratio = 11

[0151] The ZSM-48 metallosilicate in this comparative example did not contain any impurity phases other than ZSM-48. The characteristics of the ZSM-48 metallosilicate in this comparative example are shown in Tables 8 and 9 below.

[0152] The characteristics of each ZSM-48 zeolite in the examples and comparative examples are shown in Tables 8 and 9 below. In Table 8, the (M-Al) / Al molar ratio indicates the molar ratio of M atoms other than aluminum to aluminum. Also, in Table 8 below, the SiO of Comparative Example 4 ２ / M ２ O ３ Regarding the molar ratio, the oxide (M ２ O ３ Silica (SiO) relative to the total number of moles of trivalent M atoms (converted to) ２ ) Ratio of the number of moles of silicon in conversion (i.e., SiO ２ / (Al ２ O ３ +Ti ２ O ３ Instead of showing the molar ratio, SiO ２ / (Al ２ O ３ +TiO ２ ) indicates the molar ratio. In Table 9, the H peak position indicates the peak top position (temperature) of the H peak (a peak with its peak top in the range above 300°C) included in the ammonia heating desorption spectrum. For Comparative Example 4, since no H peak with its peak top in the range above 300°C could be identified, the peak top position (temperature) of the peak located on the highest temperature side is shown in parentheses.

[0153]

[0154]

[0155] [Isomerization reaction test] Each of the ZSM-48 zeolites in Examples 1 and 2, and Comparative Examples 1 to 5, and H ２ PtCl ６ By bringing the aqueous solution into contact with each ZSM-48 zeolite, H ２ PtCl ６ The material was impregnated with an aqueous solution. ２ PtCl ６Each ZSM-48 zeolite impregnated with an aqueous solution was dried at 110°C for 5 hours, and then calcined in air at 450°C for 4 hours to support platinum element on each ZSM-48 zeolite. The platinum-supported ZSM-48 zeolite was used as a catalyst for the isomerization reaction, and the isomerization reaction test described below was performed. The isomerization reaction catalyst contained 0.1% by mass of platinum element per 100% by mass of the isomerization reaction catalyst.

[0156] Each isomerization catalyst was press-molded to produce aggregated particles with an aggregation diameter of 20 to 30 mesh. One g of the aggregated sample was packed into each of the atmospheric pressure fixed-bed flow-through reaction tubes and pre-treated under the following conditions (pre-treatment conditions): Gas used: Hydrogen gas Flow rate: 25 ml / min Pressure: 0.2 MPaG Temperature: 350°C Time: 3 hours

[0157] Immediately after the completion of pretreatment, the temperature was lowered from 350°C to the predetermined reaction temperature. A fluid mixture of hydrogen and n-decane was introduced into a fixed-bed flow-through reaction tube filled with the isomerization catalyst at atmospheric pressure, and the isomerization reaction was carried out under the following conditions: Flowing fluid: Mixture of hydrogen and n-decane Pressure: 0.2 MPaG WHSV of n-decane: 1.67 h －１ (n-decane flow rate 1.67 g / h) Hydrogen / n-decane volume ratio: 656 vol / vol (hydrogen flow rate 1.5 L / h)

[0158] Ten hours after a fluid mixture of hydrogen and n-decane was passed through the system, the outlet gas of the fixed-bed flow-through reaction tube was sampled using an autosampler (product name: GHS-343A, manufactured by J-Science Co., Ltd.), and the components of the outlet gas were analyzed using gas chromatography (product name: GC-7100, manufactured by J-Science Co., Ltd.). The outlet gas was sampled while maintaining a temperature of 220°C between the outlet of the fixed-bed flow-through reaction tube and the autosampler. A capillary column (product name: Supelco® SPB-Octy, manufactured by Sigma-Aldrich) was used as the gas chromatography separation column.

[0159] The above-described test was repeated by changing the reaction temperature within the range of 250°C to 300°C until the reaction temperature that yielded the highest yield of the n-decane isomer, a C10 branched paraffin (hereinafter also referred to as "C10 branched paraffin"), was identified. The optimal reaction temperature and the yield of C10 branched paraffin at the optimal reaction temperature (hereinafter also referred to as "C10 branched paraffin yield") are shown in Table 10 below. In Table 10 below, the SiO of Comparative Example 4 ２ / M ２ O ３ The molar ratio is SiO ２ / (Al ２ O ３ +TiO ２ This indicates the molar ratio.

[0160]

[0161] The C10 branched paraffin yield was calculated using the following formula (4): C10 branched paraffin yield (%) = ([C10BP]out / [All]out) × [C10SP]cvt ... (4) In the above formula (4), [C10BP]out represents the concentration (volume / volume %) of C10 branched paraffin in the outlet gas, [All]out represents the total concentration (volume / volume %) of all products (components other than n-decane) contained in the outlet gas, and [C10SP]cvt is the conversion rate (%) of n-decane, which can be obtained from the following formula (5).

[0162] The conversion rate of n-decane ([C10SP]cvt) in equation (4) above was obtained from the following equation (5): Conversion rate of n-decane (%) = {([C10SP]in - [C10SP]out) / [C10SP]in} × 100 ... (5) In equation (5) above, [C10SP]in represents the concentration of n-decane in the gas introduced into the fixed-bed flow-through reactor (volume / volume %), and [C10SP]out represents the concentration of n-decane in the outlet gas (volume / volume %).

[0163] As shown in Table 10 above, the isomerization reaction catalyst using the ZSM-48 metallosilicate of Example 1 as a base material (hereinafter also referred to as "the isomerization reaction catalyst of Example 1") is composed of Example 1 and SiO ２ / M ２ O３ Compared to the isomerization catalyst using a ZSM-48 aluminosilicate as a base material in Comparative Example 2 (hereinafter also referred to as "the isomerization catalyst of Comparative Example 2"), which had a similar molar ratio, the yield of C10 branched paraffin at the optimal reaction temperature was higher. Furthermore, the isomerization catalyst using a ZSM-48 metallosilicate as a base material in Example 2 (hereinafter also referred to as "the isomerization catalyst of Example 2") showed a higher yield of C10 branched paraffin at the optimal reaction temperature compared to Example 2. ２ / M ２ O ３ Compared to the isomerization catalyst of Comparative Example 2, which had a similar molar ratio, the yield of C10 branched paraffin at the optimal reaction temperature was higher. Here, the isomerization reaction of n-decane is a sequential reaction in which n-decane, a linear paraffin, is modified into C10 branched paraffin via carbenium ions. If the acid strength of the ZSM-48 zeolite is too weak, the conversion rate from carbenium ions to C10 branched paraffin slows down, resulting in a low conversion rate. If the acid strength of the ZSM-48 zeolite is too strong, cracking, a competitive reaction, is more likely to occur, making it difficult to produce C10 branched paraffin. In this regard, it was inferred that the ZSM-48 metallosilicate of the example had its acid strength appropriately adjusted by the iron atoms contained as M atoms, making it easier to produce C10 branched paraffin and resulting in a high yield of C10 branched paraffin at the optimal reaction temperature. From the above results, it was found that the ZSM-48 metallosilicate used in the example is suitable as a base material for isomerization reaction catalysts.

[0164] The catalyst for the isomerization reaction in Example 1 is composed of Example 1 and SiO ２ / Al ２ O ３ Compared to the isomerization catalyst using a ZSM-48 aluminosilicate as a base material in Comparative Example 1, which had a similar molar ratio, the yield of C10 branched paraffin at the optimal reaction temperature was higher. Furthermore, the isomerization catalyst of Example 1 had a higher yield of C10 branched paraffin at the optimal reaction temperature compared to the catalyst of Example 1 with SiO ２ / Al ２ O ３ Compared to the isomerization catalyst using ZSM-48 aluminosilicate as a base material in Comparative Example 1, which had a similar molar ratio, the optimal reaction temperature was lower.

[0165] [MTO Reaction Test] The ZSM-48 zeolites of Example 1, Comparative Example 1, and Comparative Example 2 were calcined in air at 550°C for 6 hours. The calcined ZSM-48 zeolites were used as catalysts for the MTO reaction, and the following MTO reaction tests were performed.

[0166] Each MTO reaction catalyst was press-molded to produce agglomerated particles with an aggregation diameter of 20 to 30 mesh. One g of the agglomerated sample was packed into each of the atmospheric pressure fixed-bed flow-through reaction tubes and pre-treated under the following conditions (pre-treatment conditions): Gas used: Nitrogen Pressure: 0.2 MPaG Temperature: 450°C Time: 60 minutes

[0167] Immediately after the pretreatment was completed, the temperature was lowered from 450°C to 340°C, and gaseous methanol, obtained by vaporizing liquid methanol at 65°C using nitrogen as a carrier gas, was introduced into the reaction tube. The MTO reaction was then carried out under the following conditions: Carrier gas: Nitrogen Nitrogen flow rate: 250 ml / min Pressure: 0.2 MPaG Temperature: 340°C WHSV of methanol: 2.0 h －１ Methanol concentration: 10 vol%

[0168] Ten hours after the start of methanol flow, the outlet gas from the fixed-bed flow-through reactor was sampled using an autosampler (product name: GHS-343A, manufactured by J-Science Co., Ltd.), and the components of the outlet gas were analyzed using gas chromatography (product name: GC-7100, manufactured by J-Science Co., Ltd.). The outlet gas was sampled while maintaining a temperature of 220°C between the outlet of the fixed-bed flow-through reactor and the autosampler. A capillary column (product name: Supelco® SPB-Octy, manufactured by Sigma-Aldrich) was used as the gas chromatography separation column.

[0169] From the gas chromatography analysis results, the methanol conversion rate, product yield, and selectivity of each product corresponding to aliphatic hydrocarbons with four carbon atoms (hereinafter also referred to as "C4 hydrocarbons") were determined. The results are shown in Tables 11 and 12. In Table 11 below, C1 represents aliphatic hydrocarbons with one carbon atom, C2 represents aliphatic hydrocarbons with two carbon atoms, and C3+ represents aliphatic hydrocarbons with three or more carbon atoms.

[0170]

[0171]

[0172] The methanol conversion rate (%) was calculated using the following formula (6): Methanol conversion rate (%) = {([MeOH]in - [MeOH]out) / [MeOH]in} × 100 ... (6) In the above formula (6), [MeOH]in represents the methanol concentration (volume / volume %) in the gas introduced into the fixed-bed flow reactor, and [MeOH]out represents the methanol concentration (volume / volume %) in the outlet gas.

[0173] The yield of the product was determined from the following formula (7): Yield (%) = ([Pro]out / [MeOH]in) × 100 ... (7) In the above formula (7), [Pro]out represents the number of moles (mol) of carbon atoms contained in each product in the outlet gas, and [MeOH]in represents the number of moles (mol) of carbon atoms contained in methanol in the gas introduced into the fixed-bed flow reactor.

[0174] The selectivity for each product corresponding to C4 hydrocarbons was calculated using the following formula (8): Selectivity (%) = ([C4-Pro]out / [C4]out) × 100 ... (8) In the above formula (8), [C4-Pro]out represents the number of moles (mol) of carbon atoms contained in each product corresponding to C4 hydrocarbons in the outlet gas, and [C4]out represents the total number of moles (mol) of carbon atoms contained in all products corresponding to C4 hydrocarbons in the outlet gas.

[0175] As shown in Table 12, the MTO reaction catalyst using the ZSM-48 metallosilicate of Example 1 as a base material (hereinafter also referred to as "the MTO reaction catalyst of Example 1") is composed of Example 1 and SiO２ / M ２ O ３ Compared to the MTO reaction catalyst using ZSM-48 aluminosilicate as a base material in Comparative Example 2, which had a similar molar ratio, the selectivity for C4 branched olefins was higher. From this result, it was understood that the ZSM-48 metallosilicate of the example is suitable as a base material for an MTO reaction catalyst.

[0176] The catalyst for the MTO reaction in Example 1 is composed of Example 1 and SiO ２ / Al ２ O ３ Compared to the MTO reaction catalyst of Comparative Example 1, which used a ZSM-48 aluminosilicate as a base material and had a similar molar ratio (hereinafter also referred to as "the MTO reaction catalyst of Comparative Example 1"), the selectivity for C4 branched olefins was higher. Furthermore, as shown in Table 11, the MTO reaction catalyst of Example 1 also showed a higher yield of aliphatic hydrocarbons with 3 or more carbon atoms compared to the MTO reaction catalyst of Comparative Example 1.

[0177] The entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2025-5385, filed on January 15, 2025, are incorporated herein by reference as part of the disclosure of the specification.

Claims

1. Contains iron atoms and aluminum atoms as metal atoms constituting the skeletal structure, with an average crystal grain size of 0.1 μm or less, and NH ３ - A crystalline metallosilicate belonging to the ZSM-48 family, characterized by having a peak with its peak top between 310°C and 370°C in the ammonia temperature-controlled desorption spectrum measured by the TPD method.

2. A crystalline metallosilicate belonging to the ZSM-48 family according to claim 1, wherein the peak has a peak top at 320°C or higher and 365°C or lower.

3. A crystalline metallosilicate belonging to the ZSM-48 family according to claim 1 or 2, wherein the molar ratio of iron to aluminum is 0.1 or greater.

4. A crystalline metallosilicate belonging to the ZSM-48 family according to any one of claims 1 to 3, wherein the ratio of the amount of Brønsted acid to the total amount of acid, which is the sum of the Brønsted acid and Lewis acid, is 55% or more.

5. A crystalline metallosilicate belonging to the ZSM-48 family according to any one of claims 1 to 4, wherein the acid content is 0.01 mmol / g or more and 1.00 mmol / g or less.

6. A crystalline metallosilicate belonging to the ZSM-48 family according to any one of claims 1 to 5, having an aspect ratio of 10 or less.

7. A crystalline metallosilicate belonging to the ZSM-48 family according to any one of claims 1 to 6, having at least the powder X-ray diffraction peaks shown in the table below.

8. A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to any one of claims 1 to 7, comprising a crystallization step of crystallizing a raw material composition comprising amorphous aluminosilicate, an iron source, a hexamethonium source, an alkali source, and water in the presence of a seed crystal.

9. A method for producing a crystalline metallosilicate belonging to the ZSM-48 family according to claim 8, wherein the hexamethonium source is hexamethonium dihydroxyl.

10. An isomerization catalyst for isomerizing a linear paraffin into a branched paraffin, comprising a crystalline metallosilicate belonging to the ZSM-48 family as described in any one of claims 1 to 7.

11. A catalyst for the MTO reaction for producing olefins from methanol, comprising a crystalline metallosilicate belonging to the ZSM-48 family as described in any one of claims 1 to 7.

12. A method for producing branched paraffin, comprising the step of contacting the isomerization reaction catalyst described in claim 10 with a fluid containing a linear paraffin and hydrogen.

13. A method for producing an olefin, comprising the step of contacting the MTO reaction catalyst described in claim 11 with a fluid containing methanol.

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