GIS-type zeolite, adsorbent, and separation method

Abstract

This GIS-type zeolite has a silica-alumina ratio of at least 3.40, and if a, b, c and d respectively represent the peak area intensities attributed to Q4(3Al), Q4(2Al), Q4(1Al) and Q1(0Al) as observed in the 29Si-MAS-NMR spectrum, then (a+d) / (b+c)≥0.192 is satisfied.

Description

Technical Field

[0001] The present invention relates to a GIS-type zeolite, an adsorbent, and a separation method.

Background Art

[0002] Zeolites can be used as adsorbents, desiccants, separators, catalysts, catalyst supports, detergent aids, ion exchangers, wastewater treatment agents, fertilizers, food additives, cosmetic additives, etc., and are particularly useful for gas separation applications.

[0003] Among zeolites, those with a GIS structure, which is a code that defines the structure of zeolites determined by the IZA (International Zeolite Association), are called GIS-type zeolites. GIS-type zeolites are zeolites having pores composed of 8-membered oxygen rings. Such GIS-type zeolites are described, for example, in Patent Documents 1 to 4 and Non-Patent Documents 1 to 7.

[0004] In Patent Document 1, it is described that GIS-type zeolite is synthesized to effectively utilize the slag of coal combustion ash. In Patent Document 2, it is described that a zeolite film (GIS-type zeolite) is formed on the surface of an aluminum plate to improve thermal conductivity. Non-Patent Documents 1, 2, and 3 show GIS-type zeolite of silica alumina, and in none of the reports is significant carbon dioxide adsorption observed. Non-Patent Document 4 shows GIS-type zeolite of silicoaluminophosphate containing phosphoric acid, and adsorption of oxygen, nitrogen, and methane is also observed along with carbon dioxide adsorption. Also, the amount of carbon dioxide adsorption is not sufficient. In Non-Patent Documents 5 and 6, GIS-type zeolite of silica alumina is also shown, but the adsorption performance of carbon dioxide and the like is not mentioned. Patent Documents 3 and 4 show GIS-type zeolite with an adjusted crystal structure, which has an adsorption ability for carbon dioxide, but the amount of carbon dioxide adsorption is not sufficient, and there is no mention of adsorption-desorption hysteresis in the carbon dioxide adsorption-desorption isotherm. Non-Patent Document 7 shows GIS-type zeolite in which the cations in the zeolite are replaced with Li, Na, K, Rb, and Cs, which has an adsorption ability for carbon dioxide, and adsorption-desorption hysteresis is observed in the carbon dioxide adsorption-desorption isotherm.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0006]

Non-Patent Document 1

Non-Patent Document 5

Non-Patent Document 6

Non-Patent Document 7

Summary of the Invention

Problems to be Solved by the Invention

[0007] Focusing on the carbon dioxide adsorption capacity of GIS-type zeolite, for example, if carbon dioxide can be selectively removed from natural gas, its industrial utility will be remarkable. If carbon dioxide can be selectively removed from the exhaust gases of power plants and steel mills, it will also be possible to reduce carbon dioxide emissions.

[0008] When separating, recovering, and purifying carbon dioxide using an adsorbent, a pressure swing adsorption separation method, a temperature swing adsorption separation method, or a pressure-temperature swing adsorption separation method, etc. is used. As the performance of the adsorbent, it is required that the carbon dioxide adsorption amount is large, carbon dioxide is selectively adsorbed, the selectivity ratio with the gas to be separated is high, and there is no carbon dioxide adsorption-desorption hysteresis. Adsorption-desorption hysteresis represents the phenomenon of hysteresis occurring in adsorption and desorption in the carbon dioxide adsorption-desorption isotherm. When using an adsorbent, in the process of heating or evacuating to desorb and regenerate carbon dioxide, it is important that the adsorption amount during adsorption and the desorption amount during regeneration are large. The increase in adsorption-desorption hysteresis means that the adsorption amount during adsorption decreases, and accordingly, the desorption amount during regeneration also decreases. Therefore, it is difficult to say that it is a desirable characteristic when used as an adsorbent.

[0009] In Patent Documents 1 and 2, there is no mention of the adsorption of carbon dioxide by zeolite. According to the structural analysis results shown in these documents, it is difficult to say that the crystal structure necessary for selectively adsorbing carbon dioxide is clearly formed. That is, the zeolite described in Patent Documents 1 and 2 is considered to have insufficient carbon dioxide adsorption ability.

[0010] In addition, in the zeolites shown in Non-Patent Documents 1 and 2, there is no adsorption of carbon dioxide, and it is not possible to separate carbon dioxide from molecules with a larger molecular diameter than it, such as oxygen, nitrogen, and methane, by adsorption or gas permeation. The reason for this is thought to be that the 8-membered ring of the GIS-type zeolite is distorted, has an elliptical shape with a major axis of 4.5 Å and a minor axis of 3.1 Å, and carbon dioxide molecules with an average molecular diameter of 3.3 Å cannot easily penetrate into the pores. Non-Patent Document 3 discloses a GIS-type zeolite of silicoaluminophosphate. Since the bond distances and bond angles are different from those of silica alumina, the 8-membered ring pores are slightly larger, and carbon dioxide adsorption is observed, but the adsorption amount is not sufficiently high. Also, it cannot be said that the adsorption of oxygen, nitrogen, and methane is sufficiently low, and the selectivity in the separation from carbon dioxide is low. Non-Patent Documents 5 and 6 analyzed the zeolites synthesized by the present inventors according to the descriptions in Non-Patent Documents 5 and 6, 29 and it has been found that in Si-NMR, a suitable structure cannot be formed and the carbon dioxide adsorption performance of the GIS-type zeolite cannot be exhibited.

[0011] On the other hand, in Patent Documents 3 and 4, by optimizing the crystal structure of the GIS-type zeolite, GIS-type zeolites with a maximum carbon dioxide adsorption amount of 52.4 cc / g and 67.5 cc / g, respectively, are obtained. However, it is difficult to say that it is sufficient from the viewpoint of gas separation and recovery, and there is no mention of adsorption / desorption hysteresis. Non-Patent Document 7 shows GIS-type zeolites in which the cations in the zeolite are substituted with Li, Na, K, Rb, and Cs, and a GIS-type zeolite with a maximum carbon dioxide adsorption amount of 82.9 cc / g is obtained. However, adsorption / desorption hysteresis is observed in the carbon dioxide adsorption / desorption isotherm.

[0012] An object of the present invention is to provide a GIS-type zeolite having a small adsorption / desorption hysteresis in the carbon dioxide adsorption / desorption isotherm, an adsorbent containing the same, and a separation method using the same.

Means for Solving the Problems

[0013] As a result of intensive studies to solve the above problems, the inventors of the present invention have found that when the silica-alumina ratio of the GIS-type zeolite is within a predetermined range and a specific spectral area intensity ratio is within a predetermined value range in the spectrum obtained by subjecting it to Si-MAS-NMR measurement, the above problems can be solved, and thus the present invention has been completed. 29 That is, the present invention is as follows.

[0014] That is, the present invention is as follows. [1] A GIS-type zeolite, having a silica-alumina ratio of 3.40 or more, 29 wherein, when the peak area intensities attributed to Q4(3Al), Q4(2Al), Q4(1Al), and Q4(0Al) observed in the Si-MAS-NMR spectrum are a, b, c, and d, respectively, a GIS-type zeolite satisfying (a + d) / (b + c) ≥ 0.192. [2] The GIS-type zeolite according to [1], containing potassium as a cation species in the zeolite. [3] The GIS-type zeolite according to [2], wherein the ratio (K / Al) of the number concentration of potassium atoms to the number concentration of aluminum atoms in the zeolite is 0.05 or more. [4] The GIS-type zeolite according to any one of [1] to [3], wherein the ratio (A / T) of the total amount of the substances of potassium and lithium to the total amount of the substances of alkali metals (T) in the zeolite is 0.05 or more. [5] The GIS-type zeolite according to any one of [1] to [4], having a carbon atom content of 4% by mass or less. [6] The GIS-type zeolite according to any one of [1] to [5], containing silica-alumina. [7] An adsorbent containing the GIS-type zeolite according to any one of [1] to [6]. [8] Using the adsorbent according to [7], H 2 , N 2 , O2 A method for separating CO from a mixture containing two or more gases selected from the group consisting of Ar, CO, and hydrocarbons 2 and H 2 O, He, Ne, Cl 2 and NH 3 and one or more selected from the group consisting of HCl. [9] The separation method according to [8], wherein the gas is separated by a pressure swing adsorption separation method, a temperature swing adsorption separation method, or a pressure-temperature swing adsorption separation method.

Advantages of the Invention

[0015] According to the present invention, it is possible to provide a GIS-type zeolite having a small adsorption / desorption hysteresis in the adsorption / desorption isotherm of carbon dioxide, an adsorbent containing the same, and a separation method using the same.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0017] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. The present invention is not limited to the following description and can be implemented with various modifications within the scope of the gist.

[0018] The GIS-type zeolite of the present embodiment is a GIS-type zeolite having a silica-alumina ratio of 3.40 or more, 29The peak area intensities attributed to Q4(3Al), Q4(2Al), Q4(1Al), and Q4(0Al) observed in the Si-MAS-NMR spectrum are denoted as a, b, c, and d, respectively, and (a + d) / (b + c) ≥ 0.192 is satisfied (hereinafter, X = a + d, Y = b + c, and Z = X / Y may be used). The GIS-type zeolite has a small adsorption / desorption hysteresis in the carbon dioxide adsorption / desorption isotherm. Further, the GIS-type zeolite has a sufficiently large carbon dioxide adsorption amount and can adsorb carbon dioxide with a high selectivity when separating gas species such as carbon dioxide and nitrogen, and methane.

[0019] According to the present invention, by controlling the bonding modes of Si and Al present in the zeolite framework, it is possible to provide a GIS-type zeolite having a small adsorption / desorption hysteresis in the carbon dioxide adsorption / desorption isotherm, a sufficiently large carbon dioxide adsorption amount, and capable of selectively adsorbing only carbon dioxide when separating gas species such as carbon dioxide and nitrogen, and methane. The bonding modes of Si and Al affect the structural changes during the adsorption / desorption of the zeolite framework itself. For example, when a structural change occurs due to the adsorption of the adsorbate, energy is required for the structural change itself during adsorption, and adsorption / desorption hysteresis is observed. Further, if the structural change is too small, a sufficient space for the adsorbate to be adsorbed cannot be secured in the first place, resulting in a small adsorption amount. Furthermore, since the structural change also affects the pores, it contributes to the selectivity when separating gas species such as carbon dioxide and nitrogen, and methane.

[0020] The silica-alumina ratio (SiO 2 / Al 2 O 3(which represents the molar ratio of silica to alumina, hereinafter also referred to as "SAR") is 3.40 or more. The lower the SAR of the zeolite, the more hydrophilic it becomes, and the stronger the adsorption capacity for polar molecules such as carbon dioxide. When the SAR is low, the adsorption capacity is too strong, so the energy required to desorb by heating or evacuation increases. Therefore, a higher SAR is preferred. The SAR is more preferably 4.40 or more, and even more preferably 4.80 or more. The upper limit of the SAR is not particularly limited, but if the SAR is too high, the interaction with the adsorbate becomes small. Therefore, the SAR is preferably 3000 or less, more preferably 500 or less, and even more preferably 100 or less. The SAR is of the zeolite 29 It can be calculated from the area intensity of the spectrum obtained by the measurement of Si-MAS-NMR. The measurement method of the SAR is, more specifically, the method shown in the examples.

[0021] From the viewpoint of the energy required for desorption, a higher SAR is preferred. On the other hand, in the GIS-type zeolite, when the SAR increases, it is confirmed that the adsorption / desorption hysteresis in the carbon dioxide adsorption / desorption isotherm becomes apparent. In the GIS-type zeolite of the present embodiment, by controlling the bonding mode of Si and Al in the zeolite framework, the adsorption / desorption hysteresis in the carbon dioxide adsorption / desorption isotherm can be eliminated. Specifically, 29 Let the peak area intensities attributed to Q4(3Al), Q4(2Al), Q4(1Al), and Q4(0Al) observed in the Si-MAS-NMR spectrum be a, b, c, and d, respectively. When X = a + d, Y = b + c, and Z = X / Y, it is preferable to satisfy Z ≧ 0.192, more preferably 0.913 ≧ Z ≧ 0.195, and even more preferably 0.519 ≧ Z ≧ 0.199. 29Peaks such as Q4(3Al), Q4(2Al), Q4(1Al), and Q4(0Al) observed in the Si-MAS-NMR spectrum represent the bonding modes of Si and Al in the zeolite framework. X and Y, which are the sum of the area intensities, represent the sum of the abundances of these bonding modes, and Z represents the abundance ratio. Since the abundance ratio of the bonding modes of Si and Al affects the structural changes of the zeolite framework itself during adsorption and desorption, by setting Z, which is the abundance ratio of the bonding modes of Si and Al in the zeolite framework, within an appropriate range, the adsorption / desorption hysteresis in the adsorption / desorption isotherm can be eliminated.

[0022] 29 The Si-MAS-NMR spectrum is obtained by preparing a desiccator filled with water at the bottom, subjecting the zeolite placed in a sample tube at the upper part of the desiccator to a humidity conditioning treatment by holding it at room temperature (25 °C) for 48 hours, and then measuring it with a solid-state NMR measuring device. Examples of the solid-state NMR measuring device include "RESONANCE ECA700" manufactured by JEOL Ltd. (magnetic field strength: 16.44 T ( 1 resonance frequency for 1H: 700 MHz)).

[0023] The GIS-type zeolite of this embodiment 29 generally shows the following five peaks in the Si-MAS-NMR spectrum. (1) Q4(0Al): Peak of Si not bonded to Al at all via oxygen (2) Q4(1Al): Peak of Si bonded to one Al via oxygen (3) Q4(2Al): Peak of Si bonded to two Als via oxygen (4) Q4(3Al): Peak of Si bonded to three Als via oxygen (5) Q4(4Al): Peak of Si bonded to four Als via oxygen

[0024] Also, 29In the Si-MAS-NMR spectrum, their peak positions generally exist from -112 ppm to -80 ppm and can be attributed to Q4(0Al), Q4(1Al), Q4(2Al), Q4(3Al), and Q4(4Al) from the high magnetic field side. Although the peak positions can vary depending on the cation species present in the zeolite framework, generally the peak positions exist within the following ranges. (1) Q4(0Al): from -105 ppm to -112 ppm (2) Q4(1Al): from -100 ppm to -105 ppm (3) Q4(2Al): from -95 ppm to -100 ppm (4) Q4(3Al): from -87 ppm to -95 ppm (5) Q4(4Al): from -80 ppm to -87 ppm

[0025] 29 Regarding the peak area intensity of the Si-MAS-NMR spectrum, using the analysis program dmfit (version #202000113), analysis is performed using Gaussian and Lorentzian functions, and the four parameters of amplitude (height of the maximum value of the spectrum), position (spectrum position, ppm), width (full width at half maximum of the spectrum, ppm), and Gaussian / Lorentzian ratio (xG / (1 - x)L) are optimized and calculated by the least squares algorithm.

[0026] Using the peak area intensity obtained from this calculation, the peak area intensities a, b, c, d attributed to Q4(3Al), Q4(2Al), Q4(1Al), Q4(0Al), their sum X, Y, and their ratio Z are determined.

[0027] In the present embodiment, from the viewpoint of further improving the selective adsorption ability of carbon dioxide, it is preferable that the GIS-type zeolite contains silica alumina. Note that the GIS-type zeolite of the present embodiment preferably has silica and alumina as the main components (80 mass% or more). The main component is a component that occupies 80 mass% or more. The aluminum content in the GIS-type zeolite of the present embodiment is preferably 1% by mass or more, more preferably 3% by mass or more, and still more preferably 5% by mass or more. The upper limit of the aluminum content is not particularly limited as long as the SAR satisfies the predetermined range described above, and is determined by the silica content and the value of the SAR. The silicon content in the GIS-type zeolite of the present embodiment is preferably 3% by mass or more, more preferably 5% by mass or more. The upper limit of the silicon content is not particularly limited as long as the SAR satisfies the predetermined range described above, and is determined by the alumina content and the value of the SAR. The phosphorus content in the GIS-type zeolite of the present embodiment is preferably 4% by mass or less. The lower limit of the phosphorus content is not particularly limited, and may be 0% by mass or more. The Zr content in the GIS-type zeolite of the present embodiment is preferably 8% by mass or less. The lower limit of the Zr content is not particularly limited, and may be 0% by mass or more. The Ti content in the GIS-type zeolite of the present embodiment is preferably 8% by mass or less. The lower limit of the Ti content is not particularly limited, and may be 0% by mass or more. From the viewpoint of further improving the selective adsorption ability of carbon dioxide, the phosphorus atom content in the GIS-type zeolite of the present embodiment is more preferably 1.5% by mass or less, and particularly preferably 0% by mass. In addition, the contents of the above-mentioned aluminum, silicon, phosphorus, Zr, and Ti can be measured by the method described in the examples described later. Further, the contents of the above-mentioned aluminum, silicon, phosphorus, Zr, and Ti can be adjusted to the above-mentioned ranges, for example, by adjusting the composition ratio of the mixed gel used for synthesizing the GIS-type zeolite to a preferable range described later.

[0028] The carbon atom content is preferably 4% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less, based on the total amount of the GIS-type zeolite. The carbon atom content can be measured by CHN elemental analysis. By measuring the carbon atom content, the organic structure-directing agent or the altered substance thereof can be quantified. In the GIS-type zeolite of the present embodiment, an organic structure-directing agent can be used during synthesis. However, since the organic structure-directing agent remains in the pores and fills the space where carbon dioxide enters, the carbon dioxide adsorption amount decreases. Therefore, it is preferably less as described above.

[0029] From the viewpoint of improving the selective adsorption ability for carbon dioxide, it is preferable that the cation species in the GIS-type zeolite contains potassium or lithium, and more preferably contains potassium. Further, the total content of potassium and lithium in the zeolite is calculated as the ratio (A / T) of the total value (A) of the amounts of substances of potassium and lithium to the total value (T) of the amounts of substances of alkali metals in the GIS-type zeolite. A / T is preferably 0.05 or more, more preferably 0.10 or more, and even more preferably 0.15 or more. The upper limit of A / T is not particularly limited, but A / T may be 1.00 or less. A / T can be measured by subjecting the zeolite to thermal dissolution in an aqueous sodium hydroxide solution or aqua regia, appropriately diluting the resulting solution, and performing ICP-emission spectroscopic analysis. More specifically, A / T can be measured by the method described in the examples below. A / T can be adjusted by changing the ratio of potassium and lithium in the cation species of the GIS-type zeolite. The ratio (K / T) of the total value (K) of the amount of potassium to the total value (T) of the amounts of substances of each alkali metal in the GIS-type zeolite is preferably 0.05 or more, more preferably 0.10 or more, and even more preferably 0.15 or more. The upper limit of K / T is not particularly limited, but K / T may be 1.00 or less.

[0030] The above carbon atom content, potassium atom content, SAR, and 29The Si-MAS-NMR spectrum can be measured by the method described in the examples below. Also, it can be adjusted to the above-mentioned range by adjusting the synthesis conditions of the GIS-type zeolite to the preferable range described below, etc.

[0031] (Synthesis method) The method for producing a GIS-type zeolite according to this embodiment can include, for example, a step of preparing a mixed gel containing a silica source containing silicon, an alumina source containing aluminum, an alkali source containing at least one selected from alkali metals (M1) and alkaline earth metals (M2), a salt compound containing at least one selected from alkali metals (M1) and alkaline earth metals (M2), a phosphorus source containing phosphorus, an organic structure-directing agent, and water. Hereinafter, the mixed gel and each component contained therein will be described.

[0032] 〔Mixed gel〕 The mixed gel in this embodiment is a mixture containing a silica source, an alumina source, a salt compound, and water as components, and optionally containing a phosphorus source, an alkali source, and an organic structure-directing agent.

[0033] The silica source refers to the component in the mixed gel that serves as the raw material of silicon contained in the zeolite produced from the mixed gel, the alumina source refers to the component in the mixed gel that serves as the raw material of aluminum contained in the zeolite produced from the mixed gel, the salt compound refers to the component that serves as the raw material of alkali metals and / or alkaline earth metals contained in the zeolite produced from the mixed gel, the alkali source refers to the component that adjusts the alkalinity of the mixed gel, and the phosphorus source refers to the component in the mixed gel that serves as the raw material of phosphorus contained in the zeolite produced from the mixed gel.

[0034] 〔Silica source〕 The silica source is not particularly limited as long as it is commonly used, and examples include crystalline silica, amorphous silica, silicic acid, silicate, organic silicate compounds, etc. More specific examples include sodium silicate, potassium silicate, calcium silicate, magnesium silicate, fumed silica, precipitated silica, silica gel, colloidal silica, aluminosilicate, tetraethoxysilane (TEOS), trimethylethoxysilane, etc. These compounds may be used alone or in combination. Here, aluminosilicate serves as both a silica source and an aluminum source.

[0035] Among these, since highly crystalline zeolite tends to be obtained, fumed silica, colloidal silica, or precipitated silica is preferable.

[0036] 〔Aluminum source〕 The aluminum source is not particularly limited as long as it is commonly used, and specific examples include sodium aluminate, aluminum sulfate, aluminum nitrate, aluminum acetate, aluminum hydroxide, aluminum oxide, aluminum chloride, aluminum alkoxide, metallic aluminum, amorphous aluminosilicate gel, etc. These compounds may be used alone or in combination.

[0037] Among these, since highly crystalline zeolite tends to be obtained, sodium aluminate, aluminum sulfate, aluminum nitrate, aluminum acetate, aluminum hydroxide, aluminum chloride, aluminum alkoxide are preferable. From the same perspective, sodium aluminate and aluminum hydroxide are more preferable, and sodium aluminate is even more preferable.

[0038] [Salt compound] The salt compound is a compound containing alkali metals such as Li, Na, K, Rb, Cs and alkaline earth metals such as Ca, Mg, Sr, Ba, which promotes crystallization into the zeolite structure when producing zeolites. As the alkali metals and alkaline earth metals contained in the added salt compound, from the viewpoint of making it easier to form the crystal of the GIS type framework, Na and K are preferable, and Na is more preferable. Further, the salt compound may be used alone or in combination of a plurality.

[0039] Specifically, the salt compound is not limited to the following, for example, sodium sulfate, sodium sulfite, sodium thiosulfate, sodium nitrite, sodium nitrate, sodium carbonate, sodium hydrogen carbonate, sodium phosphate, sodium acetate, sodium formate, sodium citrate, sodium oxalate, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, sodium thion, sodium silicate, sodium metasilicate, sodium tetraborate, sodium chlorate, sodium perchlorate, sodium cyanide, sodium metatungstate, sodium hexahydroxidostannate(IV), sodium hexacyanoferrate(II), sodium permanganate, sodium chromate, sodium dichromate, potassium sulfate, potassium sulfite, potassium thiosulfate, potassium nitrite, potassium nitrate, potassium carbonate, potassium hydrogen carbonate, potassium phosphate, potassium acetate, potassium formate, potassium citrate, potassium oxalate, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, potassium thion, potassium silicate, potassium metasilicate, potassium tetraborate, potassium chlorate, potassium perchlorate, potassium cyanide, potassium metatungstate, potassium hexahydroxidostannate(IV), potassium hexacyanoferrate(II), potassium permanganate, potassium chromate, potassium dichromate, Lithium sulfate, lithium sulfite, lithium thiosulfate, lithium nitrite, lithium nitrate, lithium carbonate, lithium hydrogen carbonate, lithium phosphate, lithium acetate, lithium formate, lithium citrate, lithium oxalate, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, lithium thio, lithium silicate, lithium metasilicate, lithium tetraborate, lithium chlorate, lithium perchlorate, lithium cyanide, lithium metatinate, lithium hexahydroxidostannate(IV), lithium hexacyanoferrate(II), lithium permanganate, lithium chromate, lithium dichromate, Rubidium sulfate, rubidium sulfite, rubidium thiosulfate, rubidium nitrite, rubidium nitrate, rubidium carbonate, rubidium hydrogen carbonate, rubidium phosphate, rubidium acetate, rubidium formate, rubidium citrate, rubidium oxalate, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, rubidium thio, rubidium silicate, rubidium metasilicate, rubidium tetraborate, rubidium chlorate, rubidium perchlorate, rubidium cyanide, rubidium metatinate, rubidium hexahydroxidostannate(IV), rubidium hexacyanoferrate(II), rubidium permanganate, rubidium chromate, rubidium dichromate, Cesium sulfate, cesium sulfite, cesium thiosulfate, cesium nitrite, cesium nitrate, cesium carbonate, cesium hydrogen carbonate, cesium phosphate, cesium acetate, cesium formate, cesium citrate, cesium oxalate, cesium fluoride, cesium chloride, cesium bromide, cesium iodide, cesium thio, cesium silicate, cesium metasilicate, cesium tetraborate, cesium chlorate, cesium perchlorate, cesium cyanide, cesium metatinate, cesium hexahydroxidostannate(IV), cesium hexacyanoferrate(II), cesium permanganate, cesium chromate, cesium dichromate, Magnesium sulfate, magnesium sulfite, magnesium thiosulfate, magnesium nitrite, magnesium nitrate, magnesium carbonate, magnesium hydrogen carbonate, magnesium phosphate, magnesium acetate, magnesium formate, magnesium citrate, magnesium oxalate, magnesium fluoride, magnesium chloride, magnesium bromide, magnesium iodide, magnesium thio, magnesium silicate, magnesium metasilicate, magnesium tetraborate, magnesium chlorate, magnesium perchlorate, magnesium cyanide, magnesium metatungstate, magnesium hexahydroxidostannate(IV), magnesium hexacyanoferrate(II), magnesium permanganate, magnesium chromate, magnesium dichromate, Calcium sulfate, calcium sulfite, calcium thiosulfate, calcium nitrite, calcium nitrate, calcium carbonate, calcium hydrogen carbonate, calcium phosphate, calcium acetate, calcium formate, calcium citrate, calcium oxalate, calcium fluoride, calcium chloride, calcium bromide, calcium iodide, calcium thio, calcium silicate, calcium metasilicate, calcium tetraborate, calcium chlorate, calcium perchlorate, calcium cyanide, calcium metatungstate, calcium hexahydroxidostannate(IV), calcium hexacyanoferrate(II), calcium permanganate, calcium chromate, calcium dichromate, Strontium sulfate, strontium sulfite, strontium thiosulfate, strontium nitrite, strontium nitrate, strontium carbonate, strontium hydrogen carbonate, strontium phosphate, strontium acetate, strontium formate, strontium citrate, strontium oxalate, strontium fluoride, strontium chloride, strontium bromide, strontium iodide, strontium thio, strontium silicate, strontium metasilicate, strontium tetraborate, strontium chlorate, strontium perchlorate, strontium cyanide, strontium metatungstate, strontium hexahydroxidostannate(IV), strontium hexacyanoferrate(II), strontium permanganate, strontium chromate, strontium dichromate, Barium sulfate, barium sulfite, barium thiosulfate, barium nitrite, barium nitrate, barium carbonate, barium hydrogen carbonate, barium phosphate, barium acetate, barium formate, barium citrate, barium oxalate, barium fluoride, barium chloride, barium bromide, barium iodide, barium thio, barium silicate, barium metasilicate, barium tetraborate, barium chlorate, barium perchlorate, barium cyanide, barium metatitanate, barium hexahydroxidostannate(IV), barium hexacyanoferrate(II), barium permanganate, barium chromate, barium dichromate, etc. can be mentioned.

[0040] 〔Alkali source〕 When producing zeolite, the alkali source is used for the purpose of adjusting the alkalinity (pH) in the mixed gel in order to promote crystallization into the zeolite structure. The alkali to be used may be any compound that exhibits alkalinity, and it may be either an inorganic compound or an organic compound, but from the viewpoint of cost, an inorganic compound is preferably used, and more preferably an alkali metal hydroxide. Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, etc., preferably sodium hydroxide and potassium hydroxide, and more preferably sodium hydroxide. These compounds may be used alone or in combination of a plurality.

[0041] The phosphorus source is not particularly limited as long as it is generally used. Specific examples include aqueous phosphoric acid solution, sodium phosphate, aluminum phosphate, potassium phosphate, lithium phosphate, calcium phosphate, barium phosphate, etc. These compounds may be used alone or in combination of a plurality.

[0042] Among these, since zeolite with high crystallinity tends to be obtained, an aqueous phosphoric acid solution, sodium phosphate, and aluminum phosphate are preferable. From the same viewpoint, an aqueous phosphoric acid solution and sodium phosphate are more preferable, and an aqueous phosphoric acid solution is even more preferable.

[0043] [[Organic structure directing agent]] When producing zeolite by hydrothermally synthesizing a mixed gel, the organic structure directing agent is a compound that acts to promote crystallization into the zeolite structure. In the crystallization of zeolite, the organic structure directing agent can be used as necessary.

[0044] The organic structure directing agent may be of any kind as long as it can form a desired GIS-type zeolite, and it may be any one. Also, the organic structure directing agent may be used alone or in combination of a plurality.

[0045] Examples of the organic structure directing agent include, but are not limited to, amines, quaternary ammonium salts, alcohols, ethers, amides, alkylureas, alkylthioureas, cyanoalkanes, and alicyclic heterocyclic compounds containing nitrogen as a heteroatom. Preferably, alkylamines are used, and more preferably isopropylamine is used.

[0046] Such salts may have anions. Representative examples of such anions include, but are not limited to, for example, Cl - , Br - , I - and other halogen ions, hydroxide ions, acetate ions, sulfate ions, nitrate ions, carbonate ions, and hydrogen carbonate ions. Among these, halogen ions and hydroxide ions are preferable, and halogen ions are more preferable, from the viewpoint of making the crystal formation of the GIS-type framework easier.

[0047] [[Composition ratio of the mixed gel]] In this embodiment, adding a salt compound containing an alkali metal and / or an alkaline earth metal is most important for synthesizing GIS-type zeolite with an appropriate structure. The formation of zeolite involves the reaction and crystallization of a silica source and an aluminum source dissolved in an aqueous solvent. By adding a salt compound, it is possible to adjust the bonding mode and abundance ratio of Si and Al in the zeolite framework, enabling the synthesis of GIS with an ideal crystal structure.

[0048] Also, the ratio of the cation provided by the addition of the salt compound to the aluminum source is particularly important. The ratio of the cation provided by the salt compound in the mixed gel to the aluminum source is the additive molar ratio of the cation amount E to Al 2 O 3 , that is, expressed as E / Al 2 O 3 . Here, E represents the molar amount of the cation provided by the salt compound. For example, when sodium nitrate is added, the cation species Na + is generated, and in the case of sodium carbonate, 2Na + is generated. Let the additive molar amount of the cation species generated by the addition of the salt compound be represented by E. By E / Al 2 O 3 , the aggregation state of Al in the mixed gel can be changed, leading to the control of the randomness of Al during zeolite crystal formation, and enabling the synthesis of GIS-type zeolite with an ideal crystal structure. From the above perspective, it is necessary to optimally control E / Al 2 O 3 . E / Al 2 O 3 is preferably 0.1 or more and 100.0 or less, more preferably 0.5 or more and 80.0 or less, and even more preferably 0.8 or more and 50.0 or less.

[0049] Also, the ratio of water to OH - in the mixed gel (H 2 O / OH - ) is important for synthesizing GIS-type zeolite with an appropriate SAR. OH - refers to NaOH or Ca(OH) used as an alkali source2 OH derived from inorganic hydroxides such as those described above, and organic hydroxides such as tetraethylammonium hydroxide - is not included. The formation of zeolite involves a reaction in which a silica source, an alumina source, and an alkali source dissolved in an aqueous solvent crystallize, and a part of them elutes into the alkaline solvent, with an equilibrium between crystallization and redissolution occurring. OH - derived from inorganic hydroxides such as NaOH and Ca(OH) 2 and organic hydroxides such as tetraethylammonium hydroxide - is added to the mixed gel, which means shifting the equilibrium between crystallization and redissolution towards the redissolution side. Redissolution proceeds from amorphous or less crystalline parts. Therefore, by appropriately increasing OH - , the incomplete crystal parts can be redissolved and recrystallized repeatedly, increasing the formation of an ideal crystal structure. On the other hand, if OH - increases too much, excessive dissolution will occur, and no crystals will be obtained, or other crystal phases, such as the more stable ANA-type zeolite, will be formed. Also, dissolved alumina is more reactive than silica, and alumina is more likely to be incorporated into the crystal. Therefore, by appropriately adjusting OH - , the rates of crystallization and redissolution can be adjusted, the ratio of silica to alumina incorporated into the crystal can be optimized, and the SAR of the synthesized GIS-type zeolite can be optimized.

[0050] When the ratio of water to alumina (H 2 O / Al 2 O 3 ) is high, the components in the mixed gel are more likely to be uniformly dispersed, but if it is too high, the crystallization rate will be significantly reduced. Therefore, in order to synthesize a GIS-type zeolite with an optimal SAR and an optimal crystal structure, which affects the equilibrium between crystallization and redissolution, in addition to controlling H 2 O / OH - , the control of H 2 O / Al 2 O 3It is necessary to optimize the control.

[0051] From the above viewpoints, H 2 O / Al 2 O 3 and H 2 O / OH - is preferably 100 ≦ H 2 O / Al 2 O 3 ≦ 780 and 50 ≦ H 2 O / OH - ≦ 1000, more preferably 120 ≦ H 2 O / Al 2 O 3 ≦ 778 and 60 ≦ H 2 O / OH - ≦ 800, even more preferably 150 ≦ H 2 O / Al 2 O 3 ≦ 775 and 70 ≦ H 2 O / OH - ≦ 700.

[0052] The ratio of the silica source to the alumina source in the mixed gel is the molar ratio of the oxides of the respective elements, i.e., SiO 2 / Al 2 O 3 (Note that the ratio of the synthesized zeolite and the silica-alumina ratio of the mixed gel do not match. The silica-alumina ratio of the synthesized zeolite is determined by other compositions and synthesis conditions.)

[0053] The SiO 2 / Al 2 O 3 in this mixed gel is not particularly limited as long as it is a ratio at which zeolite can be formed. However, since it tends to suppress the formation of zeolites having a framework different from the GIS type framework, it is preferably 3.0 or more and 70.0 or less, more preferably 3.5 or more and 65.0 or less, and even more preferably 4.0 or more and 60.0 or less.

[0054] The ratio of the alumina source to the alkali metal and alkaline earth metal in the mixed gel is M1 with respect to Al 2 O 3 2The molar ratio of addition of O and M2O, i.e., (M1 2 O + M2O) / Al 2 O 3 is expressed as (where M1 represents an alkali metal and M2 represents an alkaline earth metal. These are calculated as oxides). Note that this (M1 2 O + M2O) / Al 2 O 3 is preferably 1.5 or more, more preferably 1.6 or more, and even more preferably 1.65 or more from the viewpoint of facilitating the formation of the GIS-type framework crystal. (M1 2 O + M2O) / Al 2 O 3 is preferably 15.0 or less, more preferably 12.0 or less, and even more preferably 10.0 or less from the viewpoint of suppressing the formation of zeolites having a framework different from the GIS-type framework.

[0055] The ratio of the phosphorus source to the aluminum source in the mixed gel is the molar ratio of the oxides of the respective elements, i.e., P 2 O 5 / Al 2 O 3 is expressed as. This P 2 O 5 / Al 2 O 3 is not particularly limited as long as it is a ratio at which zeolite can be formed, but is preferably less than 1.0, more preferably 0.6 or less, even more preferably 0.4 or less, and particularly preferably 0 from the tendency to suppress the formation of zeolites having a framework different from the GIS-type framework.

[0056] When the mixed gel contains an organic structure-directing agent, the ratio of the aluminum source to the organic structure-directing agent in the mixed gel is the molar ratio of the organic structure-directing agent to Al 2 O 3 i.e., R / Al 2 O 3is represented as (where R represents an organic structure-directing agent). From the viewpoint of easier crystallization of the GIS-type framework and / or shorter synthesis time, and excellent economy in producing zeolite, it is preferably less than 7.0, more preferably 6.0 or less, and even more preferably 5.0 or less. When an organic structure-directing agent is used, the organic structure-directing agent remains in the zeolite pores, carbon dioxide cannot enter the pores, and the adsorption amount decreases. To remove the organic structure-directing agent, it is necessary to heat at least to 400 °C or higher. However, since the crystals of the GIS-type zeolite collapse and become amorphous at 350 °C or higher, it is preferable to have less organic structure-directing agent. The preferred R / Al from this viewpoint 2 O 3 is 4.0 or less, more preferably 3.5 or less, and even more preferably 3.0 or less.

[0057] As described above, the method for producing a GIS-type zeolite according to this embodiment includes a step of preparing a mixed gel containing a silica source containing silicon, an aluminum source containing aluminum, an alkali source containing at least one selected from alkali metals (M1) and alkaline earth metals (M2), a salt compound containing at least one selected from alkali metals (M1) and alkaline earth metals (M2), a phosphorus source, and water. When calculating the molar ratios of the respective components in the mixed gel as oxides of the respective elements for silicon, aluminum, alkali metals (M1) and alkaline earth metals (M2), and the phosphorus source, the molar ratios α, β, γ, δ, ε, and ζ represented by the following formulas (1), (2), (3), (4), (5), and (6) preferably satisfy 0.1 ≦ α ≦ 100.0, 3.0 ≦ β ≦ 70.0, 1.5 ≦ γ ≦ 15.0, 0 ≦ δ < 1.0, 100 ≦ ε ≦ 780, and 50 ≦ ζ ≦ 1000, more preferably satisfy 0.5 ≦ α ≦ 80.0, 3.5 ≦ β ≦ 65.0, 1.6 ≦ γ ≦ 12.0, 0 ≦ δ ≦ 0.6, 120 ≦ ε ≦ 778, and 60 ≦ ζ ≦ 800, and even more preferably satisfy 0.8 ≦ α ≦ 50, 4.0 ≦ β ≦ 60.0, 1.65 ≦ γ ≦ 10.0, 0 ≦ δ ≦ 0.4, 150 ≦ ε ≦ 775, and 70 ≦ ζ ≦ 700. The GIS-type zeolite according to this embodiment is particularly preferably obtained by the method for producing a GIS-type zeolite according to the above-described embodiment. α = E / Al 2 O 3 (1) β = SiO 2 / Al 2 O 3 (2) γ = (M1 2 O + M2O) / Al 2 O 3 (3) δ = P 2 O 5 / Al 2 O 3 (4) ε = H 2 O / Al 2 O 3 (5) ζ = H 2 O / OH- (6)

[0058] Furthermore, in the method for producing a GIS-type zeolite according to the present embodiment, when the molar ratios α, β, γ, δ, ε, and ζ satisfy the above ranges and the mixed gel further contains an organic structure-directing agent R, it is preferable that the molar ratio η represented by the following formula (7) satisfies η ≤ 4. η = R / Al 2 O 3 (7)

[0059] It is not always necessary to have seed crystals present in the mixed gel, but it is also possible to obtain the GIS-type zeolite of the present embodiment by adding a previously produced GIS-type zeolite as seed crystals to the mixed gel.

[0060] 〔Preparation step of mixed gel〕 The preparation step of the mixed gel is not particularly limited. For example, it may include a mixing step of mixing a silica source, an aluminum source, a salt compound, water, and, if necessary, a phosphorus source, an alkali source, and an organic structure-directing agent all at once or in multiple steps, and an aging step of the mixture obtained in this mixing step.

[0061] In the mixing step, these components including a silica source, an aluminum source, a salt compound, water, and, if necessary, a phosphorus source, an alkali source, and an organic structure-directing agent can be mixed all at once or in multiple steps.

[0062] The order of mixing in multiple stages is not limited and can be appropriately selected according to the conditions used. When mixing in multiple stages, it may be carried out with or without stirring. When stirring, it is not particularly limited as long as it is a commonly used stirring method. Specific examples include methods using blade stirring, vibration stirring, rocking stirring, centrifugal stirring, etc.

[0063] The rotation speed of stirring is not particularly limited as long as it is a commonly used stirring speed. For example, it can be 1 rpm or more and less than 2000 rpm.

[0064] The temperature of the mixing step is not particularly limited as long as it is a commonly used temperature. For example, it can be -20°C or more and less than 80°C.

[0065] The time of the mixing step is not particularly limited and can be appropriately selected according to the temperature of the mixing step. For example, it can be more than 0 minutes and 1000 hours or less.

[0066] The aging step may be carried out with or without standing. When stirring in the aging step, it is not particularly limited as long as it is a commonly used stirring method. Specific examples include methods using blade stirring, vibration stirring, rocking stirring, centrifugal stirring, etc.

[0067] The rotation speed of stirring is not particularly limited as long as it is a commonly used stirring speed. For example, it can be 1 rpm or more and less than 2000 rpm.

[0068] The temperature of the aging step is not particularly limited as long as it is a commonly used temperature. For example, it can be -20°C or more and less than 80°C.

[0069] The time of the aging step is not particularly limited and can be appropriately selected according to the temperature of the aging step. For example, it can be more than 0 minutes and 1000 hours or less.

[0070] In the mixing step and aging step of the raw materials, it is considered that dissolution of the raw materials, generation of a zeolite precursor, and redissolution occur. In order to form a large periodic structure including 8-membered rings without defects, it is preferable that the formation of the zeolite precursor does not proceed excessively. Further, when the formation of the zeolite precursor proceeds excessively, since the generation of ANA-type zeolite, which has a more stable structure, tends to increase, it is preferable not to age excessively. On the other hand, it is preferable that the raw materials are sufficiently mixed and the raw material gel is in a uniform state. The total time of the mixing step and the aging step may be appropriately adjusted based on the composition of the raw materials and the like in order to obtain zeolite with an appropriate structure, and is not particularly limited. Typically, the above time is preferably 1 minute or more and less than 24 hours, more preferably 3 minutes or more and less than 23 hours, still more preferably 10 minutes or more and 18 hours or less, even more preferably 12 minutes or more and 15 hours or less, and particularly preferably 20 minutes or more and 6 hours or less.

[0071] 〔Hydrothermal synthesis step〕 In the method for producing GIS-type zeolite according to the present embodiment, it is preferable to further include a hydrothermal synthesis step in which the hydrothermal synthesis temperature is 80°C to 200°C, and the hydrothermal synthesis temperature is more preferably 100°C to 180°C. That is, preferably, the mixed gel obtained by the preparation step is hydrothermally synthesized by holding it at a predetermined temperature for a predetermined time in a stirred or static state.

[0072] The temperature of the hydrothermal synthesis is not particularly limited as long as it is a generally used temperature. However, from the viewpoint of shortening the synthesis time and excellent economic efficiency in producing zeolite, it is preferably 80°C or higher. From the viewpoint of suppressing the formation of zeolite having a framework different from the GIS-type framework, it is more preferably 90°C or higher, and still more preferably 100°C or higher. From the viewpoint of suppressing the formation of zeolite having a framework different from the GIS-type framework, it is more preferably 200°C or lower, still more preferably 180°C or lower, and still more preferably 170°C or lower. The temperature of the hydrothermal synthesis may be constant or may be changed stepwise.

[0073] The hydrothermal synthesis time is not particularly limited as long as it is a commonly used time and can be appropriately selected according to the hydrothermal synthesis temperature. From the perspective of forming the GIS framework, the hydrothermal synthesis time is preferably 3 hours or more, more preferably 10 hours or more. From the perspective of obtaining highly crystalline GIS-type zeolite, it is even more preferably 24 hours or more. From the perspective of excellent economy in zeolite production, the hydrothermal synthesis time is preferably 30 days or less, more preferably 20 days or less, and even more preferably 10 days or less.

[0074] In the hydrothermal synthesis step, the container for containing the mixed gel is not particularly limited as long as it is a commonly used container. However, when the pressure inside the container increases at a predetermined temperature or when under gas pressurization that does not inhibit crystallization, it is preferably placed in a pressure-resistant container for hydrothermal synthesis. The pressure-resistant container is not particularly limited, and for example, various shapes such as spherical, vertically long, and horizontally long can be used.

[0075] When stirring the mixed gel in the pressure-resistant container, the pressure-resistant container is rotated in the vertical direction and / or the horizontal direction, preferably in the vertical direction. When the pressure-resistant container is rotated in the vertical direction, the rotation speed is not particularly limited as long as it is within a commonly used range, but is preferably 1 - 50 rpm, more preferably 10 - 40 rpm.

[0076] In the hydrothermal synthesis step, to preferably stir the mixed gel, a method of using a vertically long pressure-resistant container and rotating it in the vertical direction can be mentioned.

[0077] 〔Separation and Drying Step〕 After the hydrothermal synthesis step, the solid product and the liquid containing water are separated. The separation method is not particularly limited as long as it is a common method, and filtration, decantation, spray drying methods (such as rotary spraying, nozzle spraying, and ultrasonic spraying), drying methods using a rotary evaporator, vacuum drying method, freeze drying method, or natural drying method, etc. can be used, and usually, separation can be achieved by filtration or decantation.

[0078] The separated product can be used as it is, or washed with water or a predetermined solvent. If necessary, the separated product can be dried. The drying temperature of the separated product is not particularly limited as long as it is a general drying temperature, but usually it is from room temperature to 150 °C or lower. The atmosphere during drying is not particularly limited as long as it is a generally used atmosphere, but usually an air atmosphere, an inert gas such as nitrogen or argon, or an atmosphere with added oxygen is used.

[0079] 〔Firing step〕 If necessary, the GIS-type zeolite can be fired and used. The firing temperature is not particularly limited as long as it is a generally used temperature, but when it is desired to remove the organic structure-directing agent, since the remaining ratio can be reduced, it is preferably 300 °C or higher, more preferably 350 °C or higher. From the point that the firing time is shortened and the economy in manufacturing zeolite is excellent, it is even more preferably 360 °C or higher. Since the crystallinity of the zeolite tends to be maintained, it is preferably less than 450 °C, more preferably 420 °C or lower, and even more preferably 400 °C or lower.

[0080] The firing time is not particularly limited as long as the organic structure-directing agent is sufficiently removed and can be appropriately selected according to the firing temperature. However, since the remaining ratio of the organic structure-directing agent tends to be reduced, it is preferably 0.5 hour or longer, more preferably 1 hour or longer, and even more preferably 3 hours or longer. Since the crystallinity of the zeolite tends to be maintained, it is preferably 10 days or shorter, more preferably 7 days or shorter, and even more preferably 5 days or shorter.

[0081] The firing atmosphere is not particularly limited as long as it is a generally used atmosphere, but usually an air atmosphere, an inert gas such as nitrogen or argon, or an atmosphere with added oxygen is used.

[0082] 〔Cation exchange〕 If necessary, the GIS-type zeolite can be cation-exchanged into a desired cation type. The cation exchange is not limited to the following, but for example, carbonates such as sodium carbonate, potassium carbonate, lithium carbonate, rubidium carbonate, cesium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, ammonium carbonate, or nitrates such as sodium nitrate, potassium nitrate, lithium nitrate, rubidium nitrate, cesium nitrate, magnesium nitrate, calcium nitrate, strontium nitrate, barium nitrate, ammonium nitrate, or salts obtained by changing carbonate ions and nitrate ions contained in the above carbonates and nitrates into halide ions, sulfate ions, carbonate ions, hydrogen carbonate ions, acetate ions, phosphate ions or hydrogen phosphate ions, and acids such as nitric acid and hydrochloric acid can be used.

[0083] The temperature of the cation exchange is not particularly limited as long as it is a general temperature for cation exchange, but usually it is from room temperature to 100 °C or lower.

[0084] When separating the zeolite after cation exchange, the separation method is not particularly limited as long as it is a general method, and filtration, decantation, spray drying methods (such as rotary spraying, nozzle spraying and ultrasonic spraying), drying methods using a rotary evaporator, vacuum drying method, freeze drying method, or natural drying method, etc. can be used, and usually it can be separated by filtration or decantation.

[0085] The separated product can be used as it is, or washed with water or a predetermined solvent. If necessary, the separated product can be dried.

[0086] The temperature for drying the separated product is not particularly limited as long as it is a general drying temperature, but usually it is from room temperature to 150 °C or lower.

[0087] The atmosphere during drying is not particularly limited as long as it is a generally used atmosphere, but usually an air atmosphere, an inert gas such as nitrogen or argon, or an atmosphere with added oxygen is used.

[0088] Furthermore, the ammonium-type zeolite can also be converted into a proton-type zeolite by calcining the zeolite.

[0089] From the viewpoint of improving the selective adsorption ability of carbon dioxide, it is preferable to contain potassium atoms as cation species in the zeolite. Also, the potassium content in the zeolite is calculated as the ratio (K / Al) of the potassium atom concentration to the aluminum atom concentration. The ratio (K / Al) of the potassium atom concentration to the aluminum atom concentration in the zeolite is preferably 0.05 or more, more preferably 0.10 or more, and even more preferably 0.15 or more. The upper limit of K / Al is not particularly limited, but when K / Al exceeds 1.00, there will be excess K ion species. Therefore, the ratio (K / Al) of the potassium atom concentration to the aluminum atom concentration in the zeolite is preferably 2.00 or less, preferably 1.50 or less, and even more preferably 1.00 or less.

[0090] The use of the GIS-type zeolite of this embodiment is not particularly limited. For example, it can be used as a separating agent or separating membrane for various gases and liquids, an electrolyte membrane for fuel cells, a filler for various resin moldings, a membrane reactor, or a catalyst for hydrocracking, alkylation, etc., a catalyst support for supporting metals, metal oxides, etc., an adsorbent, a desiccant, a detergent auxiliary, an ion exchanger, a wastewater treatment agent, a fertilizer, a food additive, a cosmetic additive, etc.

[0091] Among the above, the GIS-type zeolite of this embodiment can be preferably used as an adsorbent. That is, the adsorbent of this embodiment includes the GIS-type zeolite of this embodiment. Since the adsorbent of this embodiment is configured in this way, it can sufficiently adsorb carbon dioxide and has high selectivity of carbon dioxide adsorption with respect to the adsorption amount of methane. Therefore, for example, it can be particularly preferably used for purposes such as the selective removal of carbon dioxide from natural gas.

[0092] The adsorbent of this embodiment is not particularly limited in its configuration as long as it includes the GIS-type zeolite of this embodiment. However, as a typical configuration, the example shown in FIG. 3 can be cited. The adsorbent 1 of this embodiment illustrated in FIG. 3 includes filters 3 arranged at two locations, the inlet side and the outlet side, inside the container 2, and a plurality of zeolite particles 4 (the GIS-type zeolite of this embodiment) arranged between the two filters 3. As the filter 3, for example, a filter made of quartz can be used. For example, when the adsorbent 1 is used to remove carbon dioxide from natural gas, natural gas is introduced from the upper line, impurities are removed by the filter 3, and then carbon dioxide is selectively adsorbed and removed by the zeolite particles 4, and methane-rich gas can be taken out from the lower line. However, the target for which the adsorbent is used is not limited to natural gas, and the internal structure of the adsorbent is not limited to the example shown in FIG. 3.

[0093] (Separation method) The separation method of this embodiment uses an adsorbent containing the GIS-type zeolite of this embodiment, and separates one or more selected from the group consisting of CO, H 2 , N 2 , O 2 , CO, and hydrocarbons from a mixture containing two or more gases selected from the group consisting of CO 2 , H 2 O, He, Ne, Cl 2 , NH 3 , and HCl. In this embodiment, it is preferable to separate one or more selected from the group consisting of CO 2 , O 2 , CO, and hydrocarbons from one or more gases selected from the group consisting of CO 2 , H 2 O. The hydrocarbons are not particularly limited, and examples include methane, ethane, ethylene, propane, propylene, 1-butene, 2-butene, 2-methylpropene, dimethyl ether, acetylene, and the like.

[0094] The GIS-type zeolite of this embodiment is CO 2It has a large adsorption capacity, and physical adsorption without chemical bonding is observed. As a separation method using the GIS-type zeolite of this embodiment, although it is not particularly limited, a method with low energy during regeneration of the adsorbent and excellent economic efficiency is preferable. Specific examples of such a method are not particularly limited, but it is preferable to use any one of a pressure swing adsorption separation method, a temperature swing adsorption separation method, or a pressure-temperature swing adsorption separation method. The pressure swing adsorption separation method (PSA: Pressure Swing Adsorption) is a method of separating a gas by lowering the pressure during desorption compared to the pressure during adsorption of the gas and utilizing the difference in the adsorption amount at high pressure and the adsorption amount at low pressure. Further, the temperature swing adsorption separation method (TSA: Thermal Swing Adsorption) is a method of separating a gas by raising the temperature during desorption compared to the temperature during adsorption of the gas and utilizing the difference in the adsorption amount at low temperature and the adsorption amount at high temperature. Furthermore, a method combining these is the pressure-temperature swing adsorption and desorption method (PTSA: Pressure and Therml Swing Adsorption). These methods can be carried out under various known conditions.

Examples

[0095] Examples and the like will be given below to explain this embodiment in more detail. However, these are exemplary, and this embodiment is not limited to the following examples. A person skilled in the art can make various changes to the following examples and implement them as this embodiment, and such changes are included in the scope of the present invention as long as they satisfy the predetermined requirements of this embodiment.

[0096] 〔Atomic number concentrations of silicon, aluminum, phosphorus, potassium, and potassium content in zeolite〕 The zeolite was thermally dissolved in an aqueous sodium hydroxide solution or aqua regia, and the appropriately diluted solution was used to measure the concentrations of various elements such as silicon, aluminum, phosphorus, potassium, and lithium in the zeolite by ICP-emission spectroscopy (hereinafter also referred to as "ICP-AES", SPS3520UV-DD manufactured by Hitachi High-Technologies Corporation: apparatus name). The contents of potassium and lithium in the zeolite were calculated as the ratio (A / T) of the total amount (A) of the amounts of potassium and lithium to the total amount (T) of the amounts of each alkali metal in the zeolite. K / T was calculated in the same manner. Also, the content of potassium in the zeolite was calculated as the ratio (K / Al) of the potassium atom concentration to the aluminum atom concentration.

[0097] 〔Measurement of carbon atom content〕 Approximately 2 mg of the powder sample of the GIS-type zeolite was weighed, and the content of carbon atoms in the zeolite was measured by CHN elemental analysis (MT-6 manufactured by Yanaco Kogaku Co., Ltd.: apparatus name). The zeolite sample after adsorbing CO 2 was, in order to detect only the carbon atoms contained in the zeolite, placed in a sealed container, evacuated with a vacuum pump for 3 hours or more while heating at 200 °C, taken out into the atmosphere, allowed to stand in the atmosphere for 24 hours or more, and then weighed and subjected to elemental analysis.

[0098] 〔X-ray diffraction; crystal structure analysis〕 X-ray diffraction was performed according to the following procedure. (1) Using the dried products obtained in each example and comparative example as samples, they were ground in an agate mortar. Further, 10% by mass of crystalline silicon (manufactured by Rare Metallic Co., Ltd.) was added, and the mixture was mixed in an agate mortar until uniform to obtain a sample for structure analysis.

[0099] (2) The sample of (1) above was uniformly fixed on a non-reflecting sample plate for powder, and crystal structure analysis was performed by X-ray diffraction under the following conditions. X-ray diffractometer (XRD): Powder X-ray diffractometer "RINT2500 type" (trade name) manufactured by Rigaku Corporation X-ray source: Cu tube target (40 kV, 200 mA) Measurement temperature: 25 °C Measurement range: 5 to 60° (0.02° / step) Measurement speed: 0.2° / min Slit width (scattering, divergence, light reception): 1°, 1°, 0.15 mm

[0100] 29 Measurement of Si-MAS-NMR, SAR For zeolite 29 The measurement of Si-MAS-NMR was carried out by the following method. Also, the SAR of zeolite 29 can be determined by measuring Si-MAS-NMR. First, for the humidity adjustment of zeolite, water was placed at the bottom of a desiccator, and the zeolite placed in a sample tube was held on top of it for 48 hours. After the humidity adjustment treatment, Si-MAS-NMR 29 measurement was carried out under the following conditions. Apparatus: JEOL RESONANCE ECA700 Magnetic field strength: 16.44 T( 1 H resonance frequency 700 MHz) Nucleus to be measured: 29 Si Resonance frequency: 139.08 MHz NMR tube: 4 mmφ (zirconia rotor) Measurement method: DD / MAS (dipolar decoupling magic angle spinning) Pulse width: 45° Waiting time: 50 sec Number of integrations: 800 times (measurement time; about 22 hours) MAS: 10,000 Hz Chemical shift reference: silicone rubber (-22.34 ppm) external reference In the molded body containing GIS-type zeolite, 29 in the Si-MAS-NMR spectrum, the following five peaks are shown. (1) Q4(0Al): Peak of Si not bonded to Al at all via oxygen (2) Q4(1Al): Peak of Si bonded to one Al via oxygen ​(3) Q4(2Al): Peak of Si bonded to two Als via oxygen (4) Q4(3Al): Peak of Si bonded to three Als via oxygen (5) Q4(4Al): Peak of Si bonded to four Als via oxygen Also, 29 In the Si-MAS-NMR spectrum, their peak positions generally exist from -112 ppm to -80 ppm and can be assigned to Q4(0Al), Q4(1Al), Q4(2Al), Q4(3Al), Q4(4Al) from the high magnetic field side. Although the peak positions can vary depending on the cation species present in the zeolite framework, generally the peak positions exist in the following ranges. (1) Q4(0Al): -105 ppm to -112 ppm (2) Q4(1Al): -100 ppm to -105 ppm (3) Q4(2Al): -95 ppm to -100 ppm (4) Q4(3Al): -87 ppm to -95 ppm (5) Q4(4Al): -80 ppm to -87 ppm 29 Regarding the peak area intensity of the Si-MAS-NMR spectrum, using the analysis program dmfit (version #202000113), analysis is performed using Gaussian and Lorentzian functions, and the four parameters of amplitude (height of the maximum value of the spectrum), position (spectrum position, ppm), width (full width at half maximum of the spectrum, ppm), and Gaussian / Lorentz ratio (xG / (1 - x)L) are optimized and calculated by the least squares algorithm. The peak areas of Q4(0Al), Q4(1Al), Q4(2Al), Q4(3Al), Q4(4Al) thus obtained are denoted as A_Q4(0Al), A_Q4(1Al), A_Q4(2Al), A_Q4(3Al), A_Q4(4Al), respectively. When the total value of A_Q4(0Al), A_Q4(1Al), A_Q4(2Al), A_Q4(3Al), A_Q4(4Al) is A_total, SAR can be obtained as follows. SAR = 100 / 〔A_Q4(1Al) / 4 + 2 × A_Q4(2Al) / 4 +3×A_Q4(3Al) / 4+4×A_Q4(4Al) / 4〕×2

[0101] 〔CO 2 Adsorption amount and hysteresis amount; Gas adsorption / desorption isotherm measurement〕 The gas adsorption / desorption isotherm measurement was carried out according to the following procedure. (1) Using the dried products obtained in each of the examples and comparative examples as samples, 0.2 g was placed in a 12 mm cell (manufactured by Micro Meritics).

[0102] (2) The sample placed in the cell in (1) above was installed in a gas adsorption measurement device "3-Flex" (trade name) manufactured by Micro Meritics, and heat vacuum degassing treatment was carried out at 250 °C and 0.001 mmHg or less for 12 hours.

[0103] (3) The sample placed in the cell after the treatment in (2) above was placed in a constant temperature circulating water at 25 °C. After the temperature of the sample reached 25 ± 0.2 °C, using liquefied carbon dioxide (manufactured by Sumitomo Seika Chemical Co., Ltd., purity 99.9 mass% or more), the measurement was carried out up to an absolute pressure of 0.25 to 760 mmHg. During the above measurement, the pressure was measured over time, and when the pressure fluctuation became 0.001% / 10 sec or less, it was determined that the saturated adsorption amount was reached, and the CO 2 adsorption amount (unit: cc / g) was taken. The CO 2 adsorption amount is preferably 50 cc / g or more, and more preferably 70 cc / g or more.

[0104] (4) Following the measurement in (3) above, a pressure reduction treatment was carried out over time from an absolute pressure of 760 to 0.25 mmHg to measure the desorption isotherm of carbon dioxide. As for the equilibrium judgment, similar to (3), the measurement was carried out with the pressure fluctuation being 0.001% / 10 sec or less.

[0105] (5) As an index indicating the amount of hysteresis in the carbon dioxide adsorption / desorption isotherm, when the equilibrium adsorption amount at 75 mmHg of the adsorption isotherm measured in (3) and the equilibrium adsorption amount at 75 mmHg of the desorption isotherm measured in (4) are defined as q(Ad) and q(De), respectively, q(Ad) / q(De) is used as the index indicating the amount of hysteresis. When q(Ad) / q(De) = 1.00, it indicates no hysteresis, and the smaller q(Ad) / q(De) is, the greater the hysteresis.

[0106] 4 Adsorption amount; Gas adsorption isotherm measurement The gas adsorption isotherm measurement was carried out according to the following procedure. (1) The dried products obtained in each example and comparative example were used as samples, and 0.2 g was placed in a 12 mm cell (manufactured by Micro Meritics).

[0107] (2) The sample placed in the cell in (1) above was installed in a gas adsorption measurement device "3-Flex" (trade name) manufactured by Micro Meritics, and heat vacuum degassing treatment was performed at 250 °C and 0.001 mmHg or less for 12 hours.

[0108] (3) The sample placed in the cell after the treatment in (2) above was placed in a constant temperature circulating water at 35 °C. After the temperature of the sample reached 25 ± 0.2 °C, methane gas (manufactured by Fujii Shoko Co., Ltd., purity 99.99 mass% or more) was used to measure the absolute pressure from 0.25 to 760 mmHg. During the above measurement, the pressure was measured over time, and when the pressure fluctuation was 0.001% / 10 sec or less, it was determined that the saturated adsorption amount was reached, and the CH 4 Adsorption amount (unit: cc / g) was used. CH 4 The adsorption amount is preferably 8 cc / g or less, more preferably 4 cc / g or less, and even more preferably 1 cc / g or less.

[0109] ​​61.93 g of water, 0.403 g of sodium hydroxide (NaOH, manufactured by FUJIFILM Wako Pure Chemical Corporation), 3.39 g of sodium nitrate (NaNO3, manufactured by FUJIFILM Wako Pure Chemical Corporation), 1.64 g of sodium aluminate (NaAlO 2 ), manufactured by FUJIFILM Wako Pure Chemical Corporation), and 10.82 g of colloidal silica (Ludox AS-40, solid content concentration 40% by mass, manufactured by Grace) were mixed and stirred for 30 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 4.53, β = SiO 2 / Al 2 O 3 = 8.17, γ = Na 2 O / Al 2 O 3 = 3.99, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 431.0, ζ = H 2 O / OH - = 376.7, η = R / Al 2 O 3 = 0.00. The mixed gel was charged into a 200 mL stainless steel microbomb (manufactured by HIRO COMPANY) with a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 30 rpm, 135 °C for 4 days using a stirring type thermostatic bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdered zeolite. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS-type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS-type zeolite.

[0110] For the obtained zeolite, the aluminum and silicon concentrations were measured by ICP-AES, and as a result of calculating the silica alumina ratio, SAR = 6.90. Also, ICP-emission spectroscopy was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. The carbon atom concentration was measured by CHN analysis, but no carbon atoms were detected.

[0111] For the obtained zeolite 29 The Si-MAS-NMR spectrum is shown in Fig. 1. 29 From the Si-MAS-NMR spectrum, Z = 0.305.

[0112] For the obtained GIS-type zeolite, CO 2 adsorption isotherm and desorption isotherm were measured. The adsorption amount at 760 mmHg was 82.2 cc / g, and q(Ad) / q(De) = 0.984. Also, similarly, for the CH 4 adsorption isotherm, the adsorption amount at 760 mmHg was 6.2 cc / g.

[0113] [Example 2] 61.65 g of water, 0.60 g of a 48 mass% sodium hydroxide aqueous solution (NaOH, solid content concentration 48 mass%, manufactured by Tokuyama Soda Co., Ltd.), sodium carbonate (Na 2 CO 3 , manufactured by Tokuyama Soda Co., Ltd.) 2.27 g, sodium aluminate (NaAlO 2 , manufactured by Hokuriku Kasei Kogyosho) 1.64 g, and colloidal silica (Ludox AS-40, solid content concentration 40 mass%, manufactured by Grace) 10.82 g were mixed and stirred for 30 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 4.86, β = SiO 2 / Al 2 O 3 = 8.17, γ = Na 2 O / Al 2 O 3 = 3.99, δ = P 2 O 5 / Al 2 O 3=0.00, ε = H 2 O / Al 2 O 3 =431.2, ζ = H 2 O / OH - =527.8, η = R / Al 2 O 3 =0.00. The mixed gel was charged into a 200 mL stainless steel microbomb (manufactured by HIRO COMPANY) with a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 30 rpm, 130 °C for 5 days using a stirring type thermostatic bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdered zeolite. 1 g of the obtained zeolite was placed in 500 mL of 0.05 N aqueous potassium carbonate solution adjusted using potassium carbonate (K 2 CO 3 , manufactured by Nippon Soda Co., Ltd.), and stirred at room temperature for 3 hours at 500 rpm. The product was filtered and dried at 120 °C to obtain powdered zeolite in which part of the cations were exchanged with potassium. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0114] When each value was measured in the same manner as in Example 1, the SAR was 6.90, 29 From the Si-MAS-NMR spectrum, Z = 0.220, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.98 (= K / T), and the potassium concentration in the zeolite K / Al = 0.98. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 84.0 cc / g, and q(Ad) / q(De) = 1.000. Also, similarly, for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 0.0 cc / g.

[0115] 〔Example 3〕 141.41 g of water, 2.62 g of an aqueous sodium hydroxide solution (NaOH, manufactured by Fujifilm Wako Pure Chemical Corporation), 8.53 g of sodium nitrate (NaNO 3 , manufactured by Fujifilm Wako Pure Chemical Corporation), 3.85 g of sodium aluminate (NaAlO 2 , manufactured by Fujifilm Wako Pure Chemical Corporation), and 17.41 g of amorphous silica (Perkasil SM500, manufactured by Grace) were mixed and stirred for 1 hour to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 4.85, β = SiO 2 / Al 2 O 3 = 14.00, γ = Na 2 O / Al 2 O 3 = 5.16, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 379.3, ζ = H 2 O / OH - = 120.0, η = R / Al 2 O 3 = 0.00. The mixed gel was charged into a 300 mL stainless steel microbomb (manufactured by HIRO COMPANY) with a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 30 rpm, 130 °C for 4 days using a stirring type thermostatic bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdery zeolite. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0116] When each value was measured in the same manner as in Example 1, the SAR was 10.1, and 29From the Si-MAS-NMR spectrum, Z = 0.519 and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 80.0 cc / g, and q(Ad) / q(De) = 1.000. Also, similarly for CH 4 When the adsorption isotherm was measured, the adsorption amount at 760 mmHg was 7.2 cc / g.

[0117] [Example 4] 141.41 g of water, 2.62 g of an aqueous sodium hydroxide solution (NaOH, manufactured by FUJIFILM Wako Pure Chemical Corporation), 2.43 g of sodium nitrate (NaNO 3 , manufactured by FUJIFILM Wako Pure Chemical Corporation), 0.55 g of sodium aluminate (NaAlO 2 , manufactured by FUJIFILM Wako Pure Chemical Corporation), and 35.33 g of aluminosilicate (SIPERNAT 820A, manufactured by Evonik) were mixed and stirred for 1 hour to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 0.88, β = SiO 2 / Al 2 O 3 = 14.00, γ = Na 2 O / Al 2 O 3 = 2.62, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 242.4, ζ = H 2 O / OH - = 120.0, η = R / Al 2 O 3= 0.00. The mixed gel was charged into a 300 mL stainless steel microbomb (manufactured by HIRO COMPANY) with a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 30 rpm, 130 °C for 5 days using a stirring type thermostatic bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdery zeolite. 1 g of the obtained zeolite was put into 500 mL of 0.005 N aqueous potassium carbonate solution adjusted using potassium carbonate (K 2 CO 3 , manufactured by Nippon Soda Co., Ltd.) and stirred at room temperature for 3 hours at 500 rpm. The product was filtered and dried at 120 °C to obtain powdery zeolite in which part of the cations were exchanged with potassium. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0118] When each value was measured in the same manner as in Example 1, the SAR was 8.20, 29 from the Si-MAS-NMR spectrum, Z = 0.356, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.16 (= K / T), and the potassium concentration K / Al in the zeolite was 0.16. CO 2 When the adsorption isotherm and desorption isotherm were measured, the adsorption amount at 760 mmHg was 72.7 cc / g, and q(Ad) / q(De) = 0.991. Also, similarly, for the adsorption isotherm of CH 4 measurement was carried out, and the adsorption amount at 760 mmHg was 0.5 cc / g.

[0119] 〔Example 5〕 21.05 g of water, 0.53 g of an aqueous sodium hydroxide solution (NaOH, manufactured by Fujifilm Wako Pure Chemical Corporation), 1.37 g of sodium nitrate (NaNO 3 , manufactured by Fujifilm Wako Pure Chemical Corporation), and sodium aluminate (NaAlO 2, 1.13 g of Fuji Film Wako Pure Chemical Industries, Ltd. and 15.5 g of water glass No. 3 (manufactured by Kishida Chemical Co., Ltd.) were mixed and stirred for 1 hour to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 2.66, β = SiO 2 / Al 2 O 3 = 12.39, γ = Na 2 O / Al 2 O 3 = 6.10, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 197.9, ζ = H 2 O / OH - = 90.2, η = R / Al 2 O 3 = 0.00. The mixed gel was charged into a 100 mL stainless steel microbomb (manufactured by HIRO COMPANY) with a fluororesin inner cylinder and hydrothermally synthesized at a stirring speed of 30 rpm, 130 °C for 5 days using a stirring type thermostatic bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdery zeolite. 1 g of the obtained zeolite was placed in 500 mL of 0.003 N potassium carbonate aqueous solution prepared using potassium carbonate (K 2 CO 3 , manufactured by Nippon Soda Co., Ltd.) and stirred at 500 rpm for 3 hours at room temperature. The product was filtered and dried at 120 °C to obtain powdery zeolite in which a part of the cations was exchanged with potassium. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0120] When each value was measured in the same manner as in Example 1, the SAR was 3.40, and 29From the Si-MAS-NMR spectrum, Z = 0.192 and no carbon atoms were detected. Also, ICP-emission spectroscopy was measured and A / T = 0.11 (= K / T), and the potassium concentration in the zeolite K / Al = 0.11. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 51.2 cc / g, and q(Ad) / q(De) = 0.978. Also, similarly for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 0.8 cc / g.

[0121] [Comparative Example 1] 56.70 g of water, 0.335 g of sodium hydroxide (NaOH, manufactured by FUJIFILM Wako Pure Chemical Corporation), 1.13 g of sodium aluminate (NaAlO 2 , manufactured by FUJIFILM Wako Pure Chemical Corporation), and 12.42 g of water glass No. 3 (manufactured by Kishida Chemical Co., Ltd.) were mixed and stirred for 30 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = 8.17, γ = Na 2 O / Al 2 O 3 = 9.23, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 431.0, ζ = H 2 O / OH - = 377.0, η = R / Al 2 O 3It was 0.00. The mixed gel was charged into a 200 mL stainless steel microbomb (manufactured by HIRO COMPANY) containing a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 30 rpm, 135 °C for 4 days using a stirring type constant temperature bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdery zeolite. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0122] When each value was measured in the same manner as in Example 1, the SAR was 6.90, 29 From the Si-MAS-NMR spectrum, Z = 0.190 and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 78.1 cc / g, and q(Ad) / q(De) = 0.386. Also, similarly for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 3.5 cc / g.

[0123] 〔Comparative Example 2〕 Based on the content of Non-Patent Document 7, 143.10 g of water, 40.00 g of 50 mass% sodium hydroxide aqueous solution (NaOH, solid content concentration 50 mass%, manufactured by Aldrich), 2.70 g of aluminum powder (Al, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 75.10 g of colloidal silica (Ludox HS-40, solid content concentration 40 mass%, manufactured by Aldrich) were mixed and stirred for 24 hours to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = 10.0, γ = Na 2 O / Al 2 O 3=2.50, δ = P 2 O 5 / Al 2 O 3 =0.00, ε = H 2 O / Al 2 O 3 =220.0, ζ = H 2 O / OH - =44.0, η = R / Al 2 O 3 =0.00. The mixed gel was charged into a 300 mL stainless steel microbomb (manufactured by HIRO COMPANY) containing a fluororesin inner cylinder, and hydrothermally synthesized at a stirring speed of 60 rpm, 150 °C for 3 days using a stirring type constant temperature bath (manufactured by HIRO COMPANY) that can rotate in the vertical direction of the microbomb. The product was filtered and dried at 120 °C to obtain powdered zeolite. From the XRD spectrum, it was confirmed that the obtained zeolite was GIS type zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS type zeolite.

[0124] When each value was measured in the same manner as in Example 1, the SAR was 6.00, 29 From the Si-MAS-NMR spectrum, Z = 0.176, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the concentration of potassium in the zeolite K / Al = 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 79.8 cc / g, and q(Ad) / q(De) = 0.365. Also, similarly, for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 10.1 cc / g.

[0125] [Comparative Example 3] Based on the content of Patent Document 3, 207.30 g of water, 8.78 g of sodium hydroxide, 16.4 g of sodium aluminate, and 248.3 g of water glass No. 3 were mixed and stirred for 15 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3=0.00, β = SiO 2 / Al 2 O 3 =12.39, γ = Na 2 O / Al 2 O 3 =6.10, δ = P 2 O 5 / Al 2 O 3 =0.0, ε = H 2 O / Al 2 O 3 =197.86, ζ = H 2 O / OH - =90.17, η = R / Al 2 O 3 =0.00. The mixed gel was charged into a 1000 mL stainless steel autoclave containing a fluororesin inner cylinder, hydrothermally synthesized at 130 °C for 5 days without stirring, and the product was filtered and dried at 120 °C to obtain powdery zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS-type zeolite.

[0126] When each value was measured in the same manner as in Example 1, the SAR was 4.10, 29 From the Si-MAS-NMR spectrum, Z = 0.151, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the concentration of potassium in the zeolite K / Al = 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 52.4 cc / g, and q(Ad) / q(De) = 0.519. Also, similarly, for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 0.0 cc / g.

[0127] [Comparative Example 4] Based on the content of Non-Patent Document 1, 132.86 g of water, 15.66 g of sodium hydroxide, 7.2 g of sodium aluminate (manufactured by Alpha Aesar), and 25.56 g of colloidal silica (Ludox AS-40, solid content concentration 40% by mass) were mixed and stirred at room temperature for 24 hours to prepare a mixed gel. The composition of the mixed gel is α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = 7.96, γ = Na 2 O / Al 2 O 3 = 10.75, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 371.79, ζ = H 2 O / OH - = 19.08, η = R / Al 2 O 3 = 0.00. The mixed gel was charged into a 200 mL stainless steel autoclave with a fluororesin inner cylinder, hydrothermally synthesized at 100 °C for 7 days without stirring, the product was filtered and dried at 120 °C to obtain powdery zeolite. Furthermore, since no peaks derived from other zeolites or amorphous silica alumina were observed, it was evaluated as high-purity GIS-type zeolite.

[0128] When each value was measured in the same manner as in Example 1, the SAR was 2.60, 29 From the Si-MAS-NMR spectrum, Z = 0.188, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 8.1 cc / g, and q(Ad) / q(De) = 0.812. Also, similarly, for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 0.1 cc / g.

[0129] [Comparative Example 5] Based on the content of Non-Patent Document 3, 102.57 g of water, 2.45 g of sodium hydroxide (manufactured by Junsei Chemical Co., Ltd.), 1.15 g of sodium aluminate (manufactured by Showa Chemical Co., Ltd.), and 24.07 g of water glass (manufactured by Fujifilm Wako Pure Chemical Corporation) were mixed, and N 2 The mixed gel was prepared by stirring at 1800 rpm for 24 hours under an N 2 atmosphere. The composition of the mixed gel was α = E / Al 3 = 0.00, β = SiO 2 / Al 2 O 3 = 20.0, γ = Na 2 O / Al 2 O 3 = 14.00, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 840.00, ζ = H 2 O / OH- = 103.05, η = R / Al 2 O 3 = 0.00. The mixed gel was hydrothermally synthesized at 100 °C for 24 hours while stirring at 1000 rpm, and the product was filtered and dried at 120 °C to obtain powdery GIS-type zeolite.

[0130] When each value was measured in the same manner as in Example 1, the SAR was 4.68, 29 From the Si-MAS-NMR spectrum, Z = 0.155, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 The adsorption isotherm and desorption isotherm of were measured, and the adsorption amount at 760 mmHg was 9.8 cc / g, and q(Ad) / q(De) = 0.788. Also, similarly, for the adsorption isotherm of CH 4 When the measurement was performed, the adsorption amount at 760 mmHg was 0.2 cc / g.

[0131] [Comparative Example 6] Based on the content of Patent Document 1, 21.54 g of silicon dioxide (SiO 2 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 5.97 g of aluminum oxide (Al 2 O 3 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 1.17 g of iron oxide (Fe 2 O 3 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 0.27 g of titanium oxide (TiO 2 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 0.21 g of calcium oxide (CaO, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 0.06 g of magnesium oxide (MgO, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 0.03 g of sodium hydroxide, 0.21 g of potassium hydroxide, and 0.05 g of phosphorus oxide (P 2 O 5 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 0.53 g of carbon powder (manufactured by Strem Chemicals) were kneaded in an automatic mortar, and 17.6 g of sodium carbonate (Na 2 CO 3 , manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added and mixed, and then melted in an electric furnace at 1000 °C for 1 hour. Then, the melt was cooled and pulverized, and 149.78 g of water was added so that the molar ratio of H 2 O / Na 2 O became 50 to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 5.67, β = SiO 2 / Al 2 O 3 = 6.12, γ = Na 2 O / Al 2 O 3 = 2.84, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 142.00, ζ = H 2 O / OH - = 1848.89, η = R / Al 2 O 3 = 0.00. The mixed gel was heated in an autoclave at 100 °C for 24 hours, and the product was filtered and dried at 120 °C to obtain powdery GIS-type zeolite.

[0132] When each value was measured in the same manner as in Example 1, the SAR was 3.33, 29 From the Si-MAS-NMR spectrum, Z = 0.273, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 2.4 cc / g, and q(Ad) / q(De) = 0.043. Also, similarly for CH 4 When the adsorption isotherm was measured, the adsorption amount at 760 mmHg was 0.3 cc / g.

[0133] [Comparative Example 7] Based on the content of Non-Patent Document 6, 0.55 g of sodium aluminate, 0.35 g of sodium metasilicate (Na 2 SiO 3 , manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.), 1.43 g of fumed silica (Aerosil 300, manufactured by Nippon Aerosil Co., Ltd.) were mixed with 10 cc of 0.1 mol / L aqueous sodium hydroxide solution to obtain a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = 8.0, γ = Na 2 O / Al 2 O 3 = 1.00, δ = P 2 O 5 / Al 2 O 3 = 0.00, ε = H 2 O / Al 2 O 3 = 166.00, ζ = H 2 O / OH- = 550.00, η = R / Al 2 O 3 = 0.00. The mixed gel was placed in a stainless steel micro cylinder and heated at 200 °C for 7 days to synthesize zeolite.

[0134] When each value was measured in the same manner as in Example 1, the SAR was 6.94, 29 from the Si-MAS-NMR spectrum, Z = 0.098 and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured and A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 3.2 cc / g and q(Ad) / q(De) = 0.662. Also, similarly for the 4 adsorption isotherm of CH, the adsorption amount at 760 mmHg was 0.1 cc / g.

[0135] [Comparative Example 8] Based on the content of Patent Document 2, 18 g of sodium metasilicate pentahydrate (Na 2 O 3 Si / 5H 2 O, manufactured by Aldrich) and 210.0 g of water were mixed, and 127.1 g of triethanolamine (C 6 H 25 NO 3 , manufactured by Carl Roth GmbH) was added, and the mixture was stirred at 600 rpm for 30 minutes. To this solution, a solution prepared by mixing 2.34 g of sodium hydroxide and 148.0 g of water was added, and the mixture was stirred at room temperature at 600 rpm for 30 minutes to obtain a mixture solution containing no Al. The composition of the mixture solution was α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = ∞, γ = Na 2 O / Al 2 O 3 = ∞, δ = P 2 O 5 / Al 2 O 3 = ∞, ε = H 2 O / Al 2 O 3 = ∞, ζ = H 2 O / OH - = ∞, η = R / Al 2 O 3It was ∞. 1.134 g of aluminum powder (Al, manufactured by Wako Pure Chemical Industries, Ltd.) was charged into a 1000 mL stainless steel autoclave containing a fluororesin inner cylinder, a mixed solution was added, and hydrothermal synthesis was carried out at 95 °C for 5 days without aging time and without stirring. The product was filtered and dried at 120 °C to obtain powdery zeolite.

[0136] When each value was measured in the same manner as in Example 1, the SAR was 4.60, 29 From the Si-MAS-NMR spectrum, Z = 0.153, and the carbon atoms were 13.5 mass%. Further, ICP-emission spectroscopic analysis was measured, A / T = 0.00 (= K / T), and the potassium concentration K / Al in the zeolite was 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 1.1 cc / g, and q(Ad) / q(De) = 0.339. Similarly, for the adsorption isotherm of CH 4 When the measurement was carried out, the adsorption amount at 760 mmHg was 0.1 cc / g.

[0137] 〔Comparative Example 9〕 Based on the content of Non-Patent Document 5, 189.90 g of water, 8.17 g of aluminum isopropoxide, 17.37 g of tetraethyl orthosilicate (manufactured by Aldrich), and 176.85 g of tetramethylammonium hydroxide pentahydrate (manufactured by Aldrich) as an organic structure-directing agent were mixed and stirred for 30 minutes. After holding this solution at 0 °C for 1 hour, it was stirred with a rotary shaker for 20 hours, heated at 120 °C for 33 minutes, and then cooled at 0 °C for 15 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 = 0.00, β = SiO 2 / Al 2 O 3 = 4.78, γ = Na 2 O / Al 2 O 3 = 0.0, δ = P 2 O 5 / Al 2 O 3 = 0.0, ε = H 2 O / Al 2 O 3=253, ζ = H 2 O / OH - =51.66, η = R / Al 2 O 3 It was 4.78. The mixed gel was hydrothermally synthesized at 100 °C for 13 days, and the product was filtered and dried at 120 °C to obtain powdery zeolite.

[0138] When each value was measured in the same manner as in Example 1, the SAR was 5.00, 29 From the Si-MAS-NMR spectrum, Z = 0.150, and the carbon atoms were 13.2 mass%. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.00 (= K / T), and the concentration of potassium in the zeolite K / Al = 0.00. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 0.3 cc / g, and q(Ad) / q(De) = 0.225. Also, similarly for CH 4 When the adsorption isotherm was measured, the adsorption amount at 760 mmHg was 0.3 cc / g.

[0139] [Comparative Example 10] Based on the content of Patent Document 4, 259.10 g of water, 0.98 g of sodium hydroxide, 20.50 g of sodium aluminate, and 310.4 g of water glass No. 3 were mixed and stirred for 45 minutes to prepare a mixed gel. The composition of the mixed gel was α = E / Al 2 O 3 =0.00, β = SiO 2 / Al 2 O 3 =12.00, γ = Na 2 O / Al 2 O 3 =3.00, δ = P 2 O 5 / Al 2 O 3 =0.00, ε = H 2 O / Al 2 O 3 =200.00, ζ = H 2 O / OH - =1009.8, η = R / Al 2 O 3It was 0.00. The mixed gel was charged into a 1000 mL stainless steel autoclave containing a fluororesin inner cylinder, and hydrothermally synthesized at 110 °C for 2 days without stirring. After filtering the product and drying it at 120 °C, powdery zeolite was obtained.

[0140] 1 g of the obtained zeolite was put into 500 mL of 0.1 N potassium nitrate aqueous solution, and stirred at 60 °C for 3 hours at 400 rpm. After filtering the product and drying it at 120 °C, powdery zeolite with a part of the cations exchanged with potassium was obtained.

[0141] When each value was measured in the same manner as in Example 1, the SAR was 4.10, 29 From the Si-MAS-NMR spectrum, Z = 0.128, and no carbon atoms were detected. Also, ICP-emission spectroscopic analysis was measured, and A / T = 0.97 (= K / T), and the potassium concentration K / Al in the zeolite was 0.97. CO 2 When the adsorption isotherm and desorption isotherm of were measured, the adsorption amount at 760 mmHg was 67.5 cc / g, and q(Ad) / q(De) = 0.157. Also, similarly for CH 4 When the adsorption isotherm was measured, the adsorption amount at 760 mmHg was 0.7 cc / g.

[0142]

Table 1

[0143] α to ζ in Table 1 represent the following molar ratios. α = E / Al 2 O 3 , (E represents the added molar amount of cation species generated by the addition of a salt compound.) β = SiO 2 / Al 2 O 3 , γ = (M1 2 O + M2O) / Al 2 O 3 (Here, M1 represents an alkali metal, and M2 represents an alkaline earth metal.), δ = P2 O 5 / Al 2 O 3 、 ε = H 2 O / Al 2 O 3 、 ζ = H 2 O / OH - 、 η = R / Al 2 O 3 (R represents an organic structure-directing agent.)

Industrial Applicability

[0144] The GIS-type zeolite according to the present invention has industrial applicability as a separator and separation membrane for various gases and liquids, an electrolyte membrane for fuel cells, a filler for various resin moldings, a membrane reactor, or a catalyst for hydrocracking, alkylation, etc., a catalyst support for supporting metals, metal oxides, etc., an adsorbent, a desiccant, a detergent auxiliary, an ion exchanger, a wastewater treatment agent, a fertilizer, a food additive, a cosmetic additive, etc.

Explanation of Symbols

[0145] 1 Adsorbent 2 Container 3 Filter 4 Zeolite particles

Claims

1. A GIS-type zeolite, having a silica-alumina ratio of 3.40 or more, ２９ In the Si-MAS-NMR spectrum, the peak area intensities attributed to Q4(3Al), Q4(2Al), Q4(1Al), and Q4(0Al) are denoted as a, b, c, and d, respectively. A GIS-type zeolite that satisfies (a + d) / (b + c) ≥ 0.

192.

2. The GIS-type zeolite according to Claim 1, which contains potassium as a cation species in the zeolite.

3. The GIS-type zeolite according to Claim 2, wherein the ratio (K / Al) of the potassium atom concentration to the aluminum atom concentration in the zeolite is 0.05 or more.

4. The GIS-type zeolite according to Claim 1, wherein the ratio (A / T) of the total amount of the substance of potassium and lithium (A) to the total amount of the substance of alkali metals (T) in the zeolite is 0.05 or more.

5. The GIS-type zeolite according to Claim 1, having a carbon atom content of 4% by mass or less.

6. The GIS-type zeolite according to Claim 1, which contains silica-alumina.

7. An adsorbent containing the GIS-type zeolite according to any one of Claims 1 to 6.

8. Using the adsorbent according to claim 7, H ２ , N ２ , O ２ , Ar, CO, and a mixture containing two or more gases selected from the group consisting of hydrocarbons, CO ２ , H ２ O, He, Ne, Cl ２ , NH ３ , and a separation method for separating one or more selected from the group consisting of HCl.

9. The separation method according to Claim 8, wherein the separation of the gas is carried out by a pressure swing adsorption separation method, a temperature swing adsorption separation method, or a pressure and temperature swing adsorption separation method.

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