JP2001340755A - Porous material for adsorbing and separating gas and method of adsorbing and separating gas using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a porous material with which specific components in gas, e.g. a hydrocarbon, carbon dioxide or the like can be selectively and effi ciently adsorbed and separated, and to provide a method of adsorbing and separating the gas using the same. SOLUTION: The porous body exhibits at least one peak at the diffraction angle corresponding to (d) value of >=1 nm in a X-ray diffraction pattern and has at least one part in it, where the variation in the amount of nitrogen absorption (expressed in terms of the volume of nitrogen at standard state) is >=50 ml/g when the relative vapor pressure is changed by 0.1 in the range of the relative vapor pressure of 0.2 to 0.8, in the nitrogen adsorption isothermal line measured at a liquid nitrogen temperature. The method of adsorbing and separating the gas comprises bringing the gas into contact with the porous body which has moso-pores having a center pore diameter of 20 to 50 nm in a pore diameter distribution curve and has porosity in the wall of a pore and adsorbing and separating components contained in the gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a porous material for adsorbing and separating gas components and a method for adsorbing and separating gas components using the same.

[0002]

2. Description of the Related Art Conventionally, porous materials which can be used in a method for adsorbing / separating components in a gas include zeolites, mesoporous materials, silica gel / alumina, etc., each having the following characteristics.

[0003] Zeolite-based crystalline porous materials are used in a wide range of industrial fields as catalysts, ion exchangers, etc., depending on the physical and chemical surface properties of the porous materials. The zeolite-based crystalline porous body has a pore diameter of 0.3 to 1.3 n.
Since it has a very fine uniform structure of m, it exerts a function excellent in highly selective catalytic reaction and adsorption characteristics for low molecular weight compounds and the like.

On the other hand, a crystalline mesoporous substance (mesoporous material) having pores in a meso region of 2 to 50 nm described in JP-A-8-67578 and the like has a large specific surface area and a small pore size. Because of its excellent structural uniformity, it can be used as a selective catalyst or adsorbent for high molecular weight compounds, that is, compounds whose molecular size is about the same as the pore size. The diffusion rate of molecules from is excellent.

[0005] Amorphous porous materials such as silica gel and alumina are generally prepared by a sol-gel method, and their structure can be easily controlled by using various organic substances as templates. Such an amorphous porous material has a wide pore size distribution from micropores to mesopores and macropores, and has large macropores, so that it has excellent persistence of the function as an adsorption carrier, and has a wide pore size distribution. It can be used as an adsorption carrier or a reaction catalyst for a very wide range of organic compounds from low molecular weight to high molecular weight. JP-A-9-2958
No. 11 discloses an amorphous porous material produced by such a sol-gel method, in which micropores, mesopores, and macropores are distributed according to a fractal rule. Can be used as an adsorption carrier or a packing material for chromatography.

[0006]

However, since the above-mentioned conventional zeolite-based crystalline porous material has a very fine and uniform pore structure, it has high selectivity and adsorption for low-molecular-weight compounds. Although it shows properties, its fine pore structure limits its use as a catalyst or adsorbent for compounds having a bulky molecular structure or high molecular weight compounds, and also has a low molecular diffusion rate. There was a problem with efficiency.

On the other hand, the above-mentioned conventional crystalline mesoporous material can be used as an excellent selective catalyst or adsorbent for high-molecular-weight compounds, and has a high molecular diffusion rate due to its large pore size. On the other hand, since the pore diameter is relatively large and the pore wall is amorphous, there is a problem that it is difficult to exhibit a specific catalyst and adsorption characteristics specific to a molecular sieve such as zeolite.

Further, the above-mentioned conventional amorphous porous material has pores in all regions from micropores to mesopores and furthermore macropores. Although it can be used as a catalyst or the like, there is a problem that specific and selective catalytic reaction and adsorption / separation characteristics for a specific compound are extremely low.

As described above, none of the conventional porous substances has a sufficient performance as an adsorbent for adsorbing and separating a specific compound. It has been difficult to selectively and efficiently adsorb and separate CO ₂ causing warming using a conventional porous substance as an adsorbent.

The present invention has been made in view of the above-mentioned problems of the prior art, and is capable of selectively and efficiently adsorbing and separating specific components in a gas, for example, hydrocarbons and CO _2. It is an object of the present invention to provide a porous body for gas adsorption separation and a gas adsorption separation method using the same.

[0011]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that a pore portion is formed on a pore wall itself separating pores of a crystalline mesoporous substance (mesoporous material). By distributing (micropores), the adsorption / separation performance of specific components in a gas, especially low-molecular-weight compounds is significantly improved, and the specific components in such a gas are selectively and efficiently adsorbed and separated. It has been found that the present invention can be performed, and the present invention has been completed.

That is, the porous body for gas adsorption separation of the present invention has one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more in an X-ray diffraction pattern, and has a nitrogen adsorption measured at a liquid nitrogen temperature. In the isotherm, when the relative vapor pressure changes by 0.1 in the range of 0.2 to 0.8, the amount of change in the amount of nitrogen adsorption (the amount of nitrogen adsorption converted to the volume of nitrogen in the standard state) is A porous body having at least one portion having a volume of 50 ml / g or more, having mesopores having a central pore diameter of 2 to 50 nm in a pore diameter distribution curve, and having a porous pore wall. It is a feature.

Further, the gas adsorption separation method of the present invention has a nitrogen adsorption isotherm having one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more in an X-ray diffraction pattern, and measured at a liquid nitrogen temperature. In, the relative vapor pressure is 0.2 to
At least one portion where the amount of change in the amount of nitrogen adsorption (the amount of nitrogen adsorption converted to the volume of nitrogen in the standard state) when the relative vapor pressure changes by 0.1 in the range of 0.8 is 50 ml / g or more. A gas having a mesopore having a central pore diameter of 2 to 50 nm in a pore diameter distribution curve and having a porous pore wall by contacting a gas to adsorb and separate components in the gas. It is a method characterized by doing.

It is not clear why the adsorption / separation performance of the porous material according to the present invention is remarkably improved.
The present inventors consider as follows. That is, in the porous body according to the present invention, gas molecules rapidly diffuse into the pores through relatively large mesopores. The gas molecules are adsorbed and separated by the micropores having the molecular size existing on the surface of the mesopores (pore walls). At that time, the gas molecules are selectively adsorbed and separated (sieved) according to the size of the gas molecules and the chemical properties of the surface of the porous body. As described above, in the porous body of the present invention, since both the rapid diffusion of gas molecules and the molecular sieving function are simultaneously achieved, the specific components (for example, carbon dioxide and hydrocarbons) in the gas are replaced by other components. The present inventors believe that selective and efficient adsorption separation can be carried out from the above.

In the porous body according to the present invention, the pore walls are porous having micropores having an average pore diameter of less than 2 nm, and the total volume of the micropores is 0.05 m.
It is preferably at least 1 / g. According to such a porous body having a large micropore volume, the adsorption / separation performance tends to be further improved.

Further, in the porous body according to the present invention,
It is preferable that 60% or more of the total pore volume excluding the micropores is contained within a range of ± 40% of the central pore diameter. If the mesopores have a uniform pore structure as described above, the selectivity to gas components tends to be further improved.

Further, according to the gas adsorption / separation method of the present invention, as described above, it is possible to selectively and efficiently adsorb and separate hydrocarbons, CO _{2 and the} like. Is preferably at least one component selected from the group consisting of carbon dioxide and hydrocarbons.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail.

[Porous Body for Gas Adsorption and Separation of the Present Invention]
The porous body for gas adsorption separation of the present invention will be described.

(X-ray Diffraction Pattern) The porous body for gas adsorption separation of the present invention has one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more in the X-ray diffraction pattern. By having a regular pore structure, while sufficiently exhibiting efficient adsorption and separation characteristics as a mesoporous body, more selective adsorption and separation characteristics are imparted by the porous pore wall described later. is there.

The X-ray diffraction peak means that a periodic structure having a d value corresponding to the peak angle is present in the sample. The X-ray diffraction pattern reflects a structure in which pores are regularly arranged at intervals of 1 nm or more. That is, the mesoporous body having such a diffraction pattern has uniform pore structure and pore diameter due to the regularity of the structure indicated by the diffraction pattern. More preferably, it is preferable to have one or more peaks at a diffraction angle corresponding to a d value of 5 nm or more.

(Central Pore Diameter, Nitrogen Adsorption Amount and Pore Diameter Distribution) The porous body for gas adsorption separation of the present invention has a central pore diameter in a pore diameter distribution curve of 2 to 50 nm, preferably 2 to 50 nm.
It has a mesopore of 30 nm, more preferably 5 to 30 nm, and still more preferably 5 to 15 nm.
In the case of having such mesopores, a functional organic compound having a large molecular diameter can easily enter the pores, and the diffusion of the molecules in the pores is performed quickly, so that the efficiency is improved. Good adsorption separation becomes possible.

The above-mentioned pore diameter distribution curve is obtained as follows. That is, the pore diameter distribution curve is, for example, a value (dV / d) obtained by differentiating the pore volume (V) with the pore diameter (D).
D) is a curve obtained by plotting the pore diameter against the pore diameter (D), and the pore diameter at which the dV / dD value of the pore distribution curve is the largest (having the maximum peak) is called the central pore diameter.

Such a pore diameter distribution curve is derived from various adsorption equations, for example, from an adsorption isotherm obtained by measuring the adsorption amount of nitrogen gas. The method for measuring the adsorption isotherm is illustrated below.
The most commonly used gas in this method is nitrogen.

First, the mesoporous material was heated to the temperature of liquid nitrogen (-1).
(96 ° C.), nitrogen gas is introduced, and the adsorption amount is determined by a constant volume method or a gravimetric method. The pressure of the introduced nitrogen gas is gradually increased, and an adsorption isotherm is created by plotting the adsorption amount of the nitrogen gas with respect to each equilibrium pressure.

From this adsorption isotherm, Cranston-Inklay
The pore diameter distribution curve can be obtained by a calculation formula such as the method, the Dollimore-Heal method, and the BJH method. And, for example,
When the maximum peak in the pore diameter distribution curve is at 3.00 nm, the central pore diameter is 3.00 nm.

In the porous body for gas adsorption separation of the present invention, the relative vapor pressure changed by 0.1 in the range of 0.2 to 0.8 in the nitrogen adsorption isotherm measured at the liquid nitrogen temperature. The porous body has at least one or more portions where the amount of change in the amount of nitrogen adsorbed (the amount of nitrogen adsorbed in terms of the volume of nitrogen in a standard state) at the time becomes 50 ml / g or more. A mesoporous material that satisfies this condition has mesopores having a sufficiently uniform pore diameter, and the uniformity of the pore structure of the mesopores significantly improves the selectivity to gas components.

Further, in the porous body for gas adsorption separation of the present invention, it is preferable that 60% or more of the total pore volume excluding the micropores is contained within the range of ± 40% of the central pore diameter. preferable. This condition also indicates that the mesoporous body has mesopores having a sufficiently uniform pore size,
The uniformity of the pore structure of the mesopores tends to further improve the selectivity to gas components.

For example, when the center pore diameter in the pore diameter distribution curve is 3.00 nm, and the pore range of ± 40% includes 60% or more of the total pore volume excluding micropores, The total volume of the pores having a pore diameter in the range of 1.80 to 4.20 nm is the total pore volume excluding the micropores (the upper limit of 50 nm or less which can be measured by the gas adsorption method and the lower limit of the mesopores of 2 nm). Occupies more than 60% of the total volume of the pores having the above pore sizes). Specifically, the pore diameter in the pore distribution curve is 1.80 to 4.80.
This means that the integral value of the pore volume of the pore at 20 nm occupies 60% or more of the total integral value of the pore volume of the pores having a pore diameter of 2 to 50 nm in the pore distribution curve.

(Pore Structure) The pore shape of the porous body for gas adsorption separation of the present invention may be one that extends one-dimensionally in a tunnel shape or one in which three-dimensional box-like or spherical pores are combined. And the like. Further, as the pore structure of the porous material of the present invention, a two-dimensional hexagonal structure (p6m
m), 3-dimensional hexagonal structure (P6 ₃ / mmc), cubic structure ^{(Ia3 - d, Pm3 - n} ), lamellae, there are irregularities or the like, fine having a three-dimensional manner mesopores pores bound A pore structure is preferred. In the case of having such tunnel-shaped mesopores, the gas components can easily enter the pores, and the gas components in the pores diffuse more quickly, so that efficient adsorption separation is achieved. Tend to be possible.

(Skeleton Composition of Pore Wall) The porous body having such mesopores has a pore wall of an inorganic skeleton or an inorganic / skeleton.
It has pore walls of an organic hybrid skeleton. That is, the pore wall in the porous body for gas adsorption separation of the present invention,
It has an inorganic skeleton or an inorganic / organic hybrid skeleton.

The inorganic skeleton comprises a polymer main chain of an inorganic oxide such as silicate. The atoms replacing the silicon atoms in the silicate basic skeleton or the atoms added to the silicate skeleton are aluminum, titanium, magnesium, zirconium, tantalum, niobium, molybdenum, cobalt,
Examples include nickel, gallium, beryllium, yttrium, lanthanum, hafnium, tin, lead, vanadium, and boron.

As other inorganic skeletons, inorganic oxides such as non-Si zirconia, titania, niobium oxide, tantalum oxide, tungsten oxide, tin oxide, hafnium oxide, alumina and the like, or inorganic oxides thereof are used as basic skeletons. Among them, there may be mentioned a composite oxide in which an atom added to the silicate skeleton is incorporated.

Incidentally, various organic groups and the like may be added to the side chain of such an inorganic basic skeleton. Examples of such a side chain include a thiol group or an organic group containing a thiol group, a lower alkyl group such as a methyl group and an ethyl group, a phenyl group, a carboxyl group, an amino group, and a vinyl group.

The inorganic / organic hybrid skeleton is such that an organic group containing one or more carbon atoms is directly or oxygen-attached to a metal atom constituting the main chain at the carbon atom. Linked through an atom.
The bond between the organic group and the polymer main chain may be at one point or at two or more points. The form of the main chain is not particularly limited, and can take various forms such as a linear form, a mesh form, and a branched form.

The metal atoms in the main chain are not particularly limited, but include silicon, aluminum, zirconium, tantalum, niobium, tin, hafnium, magnesium, molybdenum, cobalt, nickel, gallium, beryllium, yttrium, lanthanum, lead, Vanadium, titanium and the like can be mentioned. Preferred are silicon, titanium, zirconium and aluminum. Among them, silicon is preferable. In the present invention, various kinds of metal atoms can be used alone or in combination of two or more kinds.

In such a main chain, the carbon atom is 1
Alternatively, it is contained in the form of an organic group having two or more carbon atoms. One or more carbon atoms in this organic group are bonded to the metal atoms constituting the main chain at one or more points. The bonding site with the metal atom may be at the terminal of the organic group or at a site other than the terminal.

The organic group is not particularly limited. In addition to various hydrocarbon groups such as alkyl chains, alkenyl chains, vinyl chains, alkynyl chains, cycloalkyl chains, benzene rings, and hydrocarbons containing benzene rings, various organic functional groups such as hydroxyl groups, amino groups, carboxyl groups, and thiol groups And various organic groups such as organic groups derived from compounds having one or more carbon atoms. The organic groups can be used alone or in combination of two or more.

The organic group bonded to the polymer main chain at two or more points is preferably a hydrocarbon group derived from an alkyl chain, and more preferably a hydrocarbon group derived from a linear alkyl chain having 1 to 5 carbon atoms. It is a hydrogen group. Specifically, a methylene group (-
Examples include alkylene chains such as CH ₂ CH ₂ —). Further, as a preferable organic group, a phenylene group (—C
₆ H ₄ -) and the like.

As the atoms constituting the inorganic / organic hybrid main chain, in addition to metal atoms and carbon atoms,
Other atoms can be included. The other atom is not particularly limited, but is preferably an oxygen atom located between metal atoms. Specifically, Si
-O, Al-O, Ti-O, Nb-O, Sn-O, Z
r-O, and the like. These bonds correspond to the bonds between metal atoms and oxygen atoms contained in polymetalloxane of various transition metals such as polysiloxane and polyalloxane. These bonds may be used alone or in combination of two or more. Further, it may contain atoms such as nitrogen, sulfur, and various halogens.

Although the main chain structure of such an inorganic / organic hybrid system has been described, various kinds of metal atoms, organic functional groups and inorganic functional groups are present on the side chain portion bonded to the atoms constituting the main chain. It may be added. For example, those having a thiol group, a carboxyl group, a lower alkyl group such as a methyl group or an ethyl group, a phenyl group, an amino group, a vinyl group and the like are preferable.

(Pore Wall Structure) In the porous body for gas adsorption separation of the present invention, the pore wall having such a skeleton is porous.

The pore wall being porous means that the pore wall has a large number of pores. Hereinafter, such pores existing in the pore wall are referred to as micropores. The pore size of the micropores is preferably 2 nm or less, more preferably,
0.2 nm or more and 2.0 nm or less, more preferably 0.1 nm or more.
5 nm or more and 1.5 nm or less. In addition, it is preferable that the diameter of the micropores is smaller than the center pore diameter of the mesopores of the porous body. Therefore, it is preferable to have micropores having a pore diameter of 0.2 nm or more and 2 nm or less with respect to a central pore diameter of 3 nm or more and 30 nm or less, and 5 nm or more and 30 nm or less.
0.5 nm or more to 1.5
It is more preferable to have micropores with a pore size of nm or less.

Detecting the presence of micropores in the mesoporous material,
Further, to determine the volume and pore size distribution, a so-called t-
A plot method can be used. What is a t-plot?
A curve in which the amount of adsorption (v) is plotted against the average film thickness (t) of the adsorption film (x-axis is the average film thickness, y-axis is the amount of adsorption). The t-plot can be determined from the adsorption isotherm of the mesoporous material (the amount of adsorption is plotted against the relative pressure of the adsorbed gas).

In order to detect the presence of micropores, first, an adsorption isotherm of the mesoporous material is obtained. Then, an approximate curve for converting the relative pressure (P / Po) into the film thickness (t) of the adsorption layer is obtained from an appropriate standard isotherm, and the relative pressure in the adsorption isotherm of the mesoporous material is determined using the approximate curve. Is converted to the film thickness of the adsorption layer.

As the standard isotherm, it is preferable to use an isotherm of a material having the same C value in the BET equation as the mesoporous material. Specifically, a non-porous material having a similar composition is used. For example, if the mesoporous material sample is a silica material, a standard isotherm created using non-porous silica is used. Note that, for the t-plot method, MRBhambh
ani et al., J. Colloid and Interface Sci., 38, 109 (19
72).

When there are no micropores in the mesoporous material,
The t-plot of the mesoporous sample is a straight line passing through the origin. On the other hand, when a micropore exists, the t-plotted straight line does not pass through the origin, and the intersection with the vertical axis (y axis), that is, the y intercept, is positive. The value of this y-intercept indicates the volume of the micropore.

Further, the pore size of the micropores can be determined by the MP method (R. SH. Mikhailet al., J. Colloid).
and Interface Sci., 26, 45 (1968)).

In this t-plot, for example, first, second, third,..., N linear slopes are created for each t value section of 4 °, 4 to 4.5 °, 4.5 to 5 °. I do. One example is shown in FIG. In this linear slope, the average thickness (t) of the adsorption layer is obtained by the following equation.

T (Å) = 10 ⁴ × (adsorption amount (V) / surface area (BET)) From the above equation, the surface area at each linear slope can be obtained. For example, the pore surface area having a thickness in the range of 4 to 4.5 ° is a difference between the surface area value obtained from the first slope and the surface area value obtained from the second slope.

The micropore volume V is calculated according to the following equation until the slope of the straight line of the linear slope no longer decreases (indicating that all the micropores are filled).

Micropore volume V (ml / g) = 10 ⁻⁴ ×
(S ₁ −S ₂ ) (t ₁ + t ₂ ) / 2 For each t value interval, the difference in the obtained pore volume ΔV = V _n
The divided by -V _n-1 the mean pore diameter _{r (= t n + t n} -1) / 2) the difference _{Δr (= r n -r n-} 1 ) of, with respect to the average pore diameter r By plotting, the distribution of micropores can be obtained. An example is shown in FIG.

In the porous body for gas adsorption separation of the present invention, the micropore volume is preferably 0.05 ml / g or more, more preferably 0.05 ml / g or more and 0.3 ml / g or less. 0.1m / g or more 0.3m
More preferably, it is 1 / g or less. When the micropore volume satisfies the above condition, the selective adsorption / separation performance by the micropore tends to be further improved.

The micropore volume is 10% of the total pore volume.
It is preferably at least 20%, more preferably at least 20% and at most 50%. This is because, by having such a pore volume ratio, the adsorption / separation characteristics due to the presence of the micropores are easily developed.

(Thickness of Pore Wall) In the porous body for gas adsorption separation of the present invention, the thickness of the pore wall is preferably 2 nm or more, more preferably 3 nm or more, and more preferably 4 nm or more. More preferably, it is most preferably 5 nm or more. This is because it is necessary to ensure the strength, heat resistance and hydrothermal resistance of the pore wall, and it is possible to secure the volume of the micropore. When there is a certain strength and micropore volume, the adsorption / separation characteristics by micropores tend to be exhibited well. The pore wall thickness is determined by the lattice constant a ₀ (a ₀ = d) determined by X-ray diffraction.
₁₀₀ × 2 / 1.732) and can be determined by subtracting the center pore diameter.

Examples of the form of the porous body for gas adsorption separation of the present invention include powders, granules, support membranes, free-standing membranes, transparent membranes, alignment membranes,
Spherical, fibrous, burning on the substrate, and particles having a distinct morphology of μm size can be mentioned. The preferred form is a powder.

(Method for Producing Porous Body) The porous body for gas adsorption separation of the present invention can be preferably obtained by the following production method.

That is, the porous body for gas adsorption separation of the present invention is basically formed by compressing the skeletal component constituting the mesoporous body by using a surfactant as a template (template) for obtaining a pore structure. It is obtained by polymerizing and then removing the surfactant.

(Skeletal Component) As the inorganic skeleton component for forming the inorganic polymer main chain by condensation polymerization, alkoxysilane, sodium silicate, or silica can be used. As the alkoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane can be used. These skeletal components form a silicate skeleton.

In addition, alkylalkoxysilanes having a lower alkyl group such as methyltrimethoxysilane and ethyltrimethoxysilane, and alkoxysilanes having other organic groups or functional groups can also be used. Other examples of the organic group include a phenyl group. Examples of the functional group include an amino group, a carboxyl group, and a thiol group. When these organic groups or functional group-containing alkoxysilanes are used, the organic groups or functional groups are introduced into the silicate basic skeleton. These alkoxysilanes and the like can be used alone or in combination of two or more.

In addition to sodium silicate, silica, or alkoxysilane, a compound containing another element or an inorganic skeleton component can be used. For example, by adding pseudoboehmite, sodium aluminate, aluminum sulfate or dialkoxyaluminotrialkoxysilane as an Al source, a mesoporous body having a basic skeleton composed of SiO ₂ —Al ₂ O ₃ can be synthesized. Further, Si is replaced with Ti, Zr,
Oxidized compounds replaced with metals such as Ta, Nb, Sn, Hf can also be used. As a result, a metallosilicate-based mesoporous material (SiO ₂ -MO _{n / 2} ) containing various metals (M ^{n +} ; n is a charge of the metal) in the silicate skeleton can be obtained. For example, a titanate compound such as Ti (OC ₂ H ₅ ) ₄ , vanadyl sulfate (VOSO ₄ ), boric acid (H ₃ BO ₃ ) or manganese chloride (MnCl ₂ ) is added to an alkoxysilane to perform a co-condensation reaction. And a metallosilicate-based mesoporous material into which Ti, V, B or Mn is introduced, respectively.

The following organometallic compounds can be used as the skeleton component of the inorganic / organic composite system which forms the inorganic / organic composite system skeleton by condensation polymerization. The organic group contained in the organometallic compound can introduce an organic group into the basic skeleton of the mesoporous body. The metal compound has an organic group bonded to two or more metal atoms, and an organic metal compound having one or more alkoxyl groups or halogen groups for each of the two or more metal atoms bonded to the organic group is used. That is, in this organometallic compound, the organic group has one or more carbon atoms, and the carbon atom is
It is bonded to two or more metal atoms.

The metal atom is not particularly limited.
Examples include silicon, aluminum, zirconium, tantalum, niobium, tin, hafnium, magnesium, molybdenum, cobalt, nickel, gallium, beryllium, yttrium, lanthanum, lead, and vanadium. As the organometallic compound used in the present invention, various kinds of metal atoms can be used alone or in combination of two or more kinds.

The organic group in this organometallic compound is 1
Or it has two or more carbon atoms, and has two or more bonding sites with a metal atom in the carbon atom. 1 in organic group
One carbon atom may have two or more bonding sites with a metal atom. In two or more different carbon atoms,
Each may have a bonding site with a metal atom.

The organic group is bonded to two or more metal atoms.
There is no particular limitation other than the matching. Alkyl chain,
Alkenyl chain, vinyl chain, alkynyl chain, cycloalkyl
Chain, benzene ring, hydrocarbon containing benzene ring, etc.
In addition to hydrocarbons, various types, hydroxyl groups, carboxyl groups, thiols
With one or more carbon atoms and an organic functional group such as
Use of various types such as organic groups derived from compounds
Can be. Specifically, a methylene group (—CH_TwoCH
_Two-) And phenylene groups (-C₆H
_Four-).

Further, the organometallic compound according to the present invention has one or more alkoxyl groups or halogen groups at each metal atom to which the organic group is bonded. The hydrocarbon group constituting the alkoxyl group is a chain, cyclic or alicyclic hydrocarbon group. It is preferably an alkyl group, and more preferably a chain alkyl group having 1 to 5 carbon atoms. As the halogen group, various halogen atoms, chlorine, bromine, fluorine, iodine and the like can be used. At least one alkoxyl group or halogen group may be provided for each metal atom to which the organic group is bonded, and more alkoxyl groups or halogen groups may be provided.

Specific examples of such organometallic compounds include:
Typically, a metal alkoxy group or a metal halo
An organometallic compound having a gen group can be given.
For example, (CH_Three O)_ThreeSi-CH_Two-CH_Two-Si
(OCH_Three)_ThreeThere is. -CH _Two-CH_Two-Part-
C₆H_Four(CH)_ThreeO)
_ThreeSi-C₆H_Four-Si (OCH_Three)_ThreeAlso use
Can be. Further, Si is changed to Al, Ti, Zr, Ta, N
Uses compounds replaced with other metals such as b, Sn, Hf
can do. In addition, this methoxyl group is
Compounds substituted with groups can also be used. In addition,
The alkoxyl group and the halogen group are used in the condensation polymerization reaction.
It is a hydrolysis group.

The organometallic compound may contain, in addition to metal atoms and organic groups, other atoms and organic or inorganic functional groups. The other atoms and functional groups are not particularly limited, and may include atoms such as nitrogen, sulfur, and various halogens, or may include functional groups containing these atoms.

As described above, as the organometallic compound, those obtained by variously combining the various organic groups and various metal atoms described above can be obtained. The organometallic compounds can be used alone or in combination of two or more. Further, only this organic metal compound may be used as a skeleton component, or another skeleton component such as alkoxysilane and this organic metal compound may be used as a skeleton component.

(Template) As a surfactant serving as a template, a nonionic surfactant can be used. Although it is not particularly limited as long as it is a nonionic surfactant, for example, a polyethylene oxide-based nonionic surfactant having a hydrocarbon chain as a hydrophobic portion and polyethylene oxide as a hydrophilic portion can be used. . As such a surfactant, C ₁₆ H ₃₃ (OC
H ₂ CH ₂ ) OH (hereinafter, such a structure is referred to as C ₁₆ EO ₂
Abbreviated description. _{), C 12 EO 4, C} 16 EO 10, C 16
_{EO 20, C 18 EO 10,} C 16 EO 20, C 18 H 35 EO 10, C
₁₂ EO ₂₃ and C ₁₆ EO ₁₀ can be exemplified.

Further, as the hydrophobic portion, there are various sorbitan fatty acid esters having fatty acids such as oleic acid, lauric acid, stearic acid and palmitic acid. Specifically, CH ₃ C (CH ₃ ) CH ₂ C (CH ₃ ) ₂ C ₆ H ₄
(OCH ₂ CH ₂ ) _x OH (x is an average of 10) Tr
itonX-100 (Aldrich), polyethylene oxide (20) sorbitan monolaurate (Twe
en20, Aldrich) and polyethylene oxide (20) sorbitan monopalmitate (Tween4
0), polyethylene oxide (20) sorbitan monostearate, polyethylene oxide (20) sorbitan monooliate (Tween 60), sorbitan monopalmitate (Span 40) and the like. Polyethylene oxide-based nonionic surfactants can be 2
A combination of more than one type can also be used.

Further, a triblock copolymer having three polyalkylene oxide chains can also be used. In particular, it is preferable to use a triblock copolymer having a polyethylene oxide chain-polypropylene oxide chain-polyethylene oxide chain. This surfactant has a polypropylene oxide chain at the center and polyethylene oxide chains on both sides thereof, and has a structure having hydroxyl groups at both terminals. The basic structure of this triblock copolymer is represented by (EO) _x (PO)
Expressed as _y (EO) x. x and y are not particularly limited. For example, a triblock copolymer composed of x = 5 to 110 and y = 15 to 70 can be mentioned. Preferably, it is a triblock copolymer where x = 15-20 and y = 50-60. In addition, 15, 16, 18, 1
Any x value selected from 9, 20 and y = 50 to
(EO) _x (PO) _y (EO) _x obtained by combining any of the y values which are integers included in 60 with a y-value is a preferred triblock copolymer.

Further, a triblock copolymer ((PO) _x (EO) _y (PO) _x ) having a polypropylene oxide chain-polyethylene oxide chain-polypropylene oxide chain in which the blocks are reversely arranged can also be used. Also for this copolymer, in particular, x,
Although y is not limited, the ranges of x = 5 to 110 and y = 15 to 70 are preferable, and more preferably, x = 15 to 20, y
= 50-60.

As the triblock copolymer, specifically, EO ₅ PO ₇₀ EO ₅ , EO ₁₃ PO ₃₀ EO ₁₃ , EO
₂₀ PO ₃₀ EO ₂₀ , EO ₂₆ PO ₃₉ EO ₂₆ , EO ₁₇ PO ₅₆ E
O ₁₇ , EO ₁₇ PO ₅₈ EO ₁₇ , EO ₂₀ PO ₇₀ EO ₂₀ , EO
₈₀ PO ₃₀ EO ₈₀ , EO ₁₀₆ PO ₇₀ EO ₁₀₆ , EO ₁₀₀ P
O ₃₉ EO ₁₀₀ , EO ₁₉ PO ₃₃ EO ₁₉ , EO ₂₆ PO ₃₉ EO
₂₆ mag is available. Preferably, EO ₁₇ PO ₅₆ EO ₁₇ ,
EO ₁₇ PO ₅₈ EO _{17 and the} like. These triblock copolymers are commercially available from BASF and others,
Further, a triblock copolymer having desired x and y values can be obtained at a small-scale production level. The triblock copolymer can be used alone or in combination of two or more.

Further, two nitrogen atoms of ethylenediamine
Each have two polyethylene oxide chains-polypropylene
Star die block with pyrene oxide chain attached
Copolymers can also be used. For example, (EO₁₁₃P
O_{twenty two})_TwoNCH_TwoCH_TwoN (PO _{twenty two}EO₁₁₃)_Two, (E
O_ThreePO₁₈)_TwoNCH_TwoCH_TwoN (PO₁₈EO_Three)_Two,
(PO₁₉EO₁₆)_TwoNCH_TwoCH_TwoN (EO₁₆PO₁₉)
_TwoAnd the like. Star die block kori
May be used alone or in combination of two or more.
Can be.

Also, primary alkylamines and the like can be used as the nonionic surfactant. The obtained pore size can be controlled by the type of the surfactant used, specifically, by the length of the hydrophobic portion such as the alkyl chain of the surfactant.

(Polycondensation) Next, a porous body for gas adsorption separation is obtained from a reaction system (liquid) containing these skeleton components and a surfactant. The solvent in the condensation polymerization reaction is water, an organic solvent,
Although a mixed solvent of water and an organic solvent can be used,
Preferably, water is used.

The reaction system of the polycondensation reaction is not particularly limited to alkaline, neutral or acidic, but is preferably acidic. Specifically, the pH is preferably 1 or less. For example, hydrochloric acid, boric acid, bromic acid, fluoric acid, iodic acid, nitric acid, sulfuric acid, phosphoric acid, and the like can be used.
In the present invention, the acid can be used alone or in combination of two or more. The acid used in the present invention is preferably hydrochloric acid or sulfuric acid. It is particularly preferable to use hydrochloric acid to adjust the pH to 0.5 or less.

In order to obtain the porous body of the present invention, it is preferable that the concentration of the surfactant is low. Preferably, it is less than 29.67 g / l based on the total amount of the solvent used in the reaction system. This is because micropores are not formed at 29.67 g / l or more. Further, it is preferably at least 7 g / l. If the amount is less than 7 g / l, it is difficult to form micelles. Preferably, the upper limit concentration is 29 g / l or less, further preferably 25 g / l or less, more preferably 20 g / l or less. The lower limit concentration is
10 g / l or more is preferable, and 12 g / l is more preferable.
That is all. In addition, about 15 g / l is preferable.

It is preferable that the amount of the skeleton component is not less than 0.012 mol per 1 g of the surfactant.

The method of mixing the respective reaction system components is not particularly limited. However, it is preferable to mix a surfactant with a solvent and simultaneously or successively add an acid to form a preferable acidic atmosphere, and then to add a skeleton component. The temperature and time of the mixed system in which the surfactant and the acid are added are not particularly limited as long as a solution in which the surfactant is uniformly dissolved can be obtained.
It is preferable that the temperature is not lower than 100 ° C and not higher than 100 ° C.

If the surfactant and the skeletal component can be subjected to polycondensation, for example, if they are present in an acidic atmosphere, the polycondensation reaction starts. The skeleton component may be added all at once, or may be added little by little while stirring. The temperature at the time of adding the skeleton component is not particularly limited, but is preferably 35 ° C or more and 80 ° C or less, more preferably 40 ° C or more and 45 ° C or less. Also, the time required for the addition is not particularly limited,
Preferably, the time is one minute or longer.

In the reaction system, the molar ratio of each component,
That is, the molar ratio of the skeleton component: the surfactant: the hydrochloric acid: the solvent is 0.042 to 0.175: 0.00073 to 0.0.
030: 1: 27.79. In this case, the solvent is more preferably water. The molar ratio of the skeleton component: surfactant (skeleton component / surfactant) is
It is preferably 60 or more. It is more preferably 90 or more, and further preferably 120 or more. By increasing the molar ratio, the pore diameter can be reduced, and the pore wall thickness can be increased. At the same time,
The pore volume can also be reduced.

By increasing the molar ratio (by increasing the pore wall thickness), the micropore volume can be increased. Further, the increase in the molar ratio decreases the pore volume and increases the micropore volume, so that the ratio (%) of the micropore volume to the pore volume can be increased.

When the molar ratio is to be increased, the amount of the surfactant is reduced and / or the amount of the skeleton component is increased. If the concentration of the surfactant is not more than a certain concentration, specifically, 29.67
If it is less than g / l, more preferably 15 g / l or less, effects such as effectively increasing the micropore volume can be obtained by increasing the amount of the skeleton component used.
The amount of the skeleton component used is preferably 0.012 mol or more per 1 g of the surfactant.

The polycondensation reaction temperature varies depending on the type and concentration of the surfactant and the skeletal component used.
The heating is performed in the range of not less than 100 ° C. and preferably not less than 35 ° C. and not more than 80 ° C. In particular, when a triblock copolymer is used as a surfactant, the temperature is preferably from 40 ° C to 45 ° C. The lower the temperature, the higher the regularity of the product structure tends to be. Also, the lower the temperature, the smaller the pore diameter and the greater the wall thickness of the pores.

The polycondensation time varies depending on the components of the reaction system, but is usually in the range of 8 to 24 hours. Further, the reaction may be performed in a standing state or a stirring state, or a combination of the stirring state and the standing state. Further, the temperature condition can be changed depending on the reaction state.

The pore size of the porous body of the present invention can be controlled by adding a hydrophobic compound such as trimethylbenzene or triisopropylbenzene in addition to the surfactant.

(Hydrothermal treatment) After the polycondensation reaction, if necessary, a hydrothermal treatment is carried out. That is, before performing the process of removing the surfactant from the porous precursor (that is, the one in which the surfactant is still filled in the pores), a hydrothermal treatment is performed as follows.

The porous precursor is dispersed in an aqueous solution containing the same surfactant as used in the polycondensation reaction (typically, a surfactant concentration equal to or lower than that in the polycondensation reaction). Then, the precursor is subjected to hydrothermal treatment within a range of 50 ° C. or more and 200 ° C. or less. Specifically, the reaction solution is heated as it is or after dilution. The heating temperature is preferably 60
The temperature is from 100C to 100C, and more preferably from 70C to 80C. The pH at this time is slightly alkaline, and is preferably 8 or more and 8.5 or less. It may be adjusted appropriately with hydrochloric acid or sodium hydroxide. The processing time is not particularly limited, but is preferably 1 hour or more, and more preferably 3 hours to 8 hours. The treatment may be continued for a longer time, but if the treatment is carried out for a too long time, there is no noticeable difference in the effect. Note that the hydrothermal treatment is preferably performed while stirring the treatment liquid. After this hydrothermal treatment, the precursor is filtered and dried, and an excess treatment liquid is removed.
After the precursor is dispersed in the aqueous solution, a stirring treatment may be performed at room temperature for several hours before starting the hydrothermal treatment. Thereby, the following effects based on the hydrothermal treatment can be further enhanced.

As a result of performing the hydrothermal treatment as described above, the strength and structural regularity of the porous body after removing the surfactant can be improved. For this reason, a mesoporous body having excellent pore stability and structural regularity, that is, excellent uniformity of pore distribution, can be provided as compared with those not subjected to the hydrothermal treatment. Therefore, for example, by subjecting a porous precursor having a hexagonal structure to this hydrothermal treatment, the size of the pores in the mesoporous body (final product) can be determined by ± It can be easily made uniform so that the range of 40% includes 60% or more of the total pore volume.

(Removal of Surfactant) After the condensation polymerization reaction or after the hydrothermal treatment, the formed precipitate or gel was filtered,
If necessary, a solid product is obtained by washing and drying. The surfactant is then removed from the solid product. The removal of the surfactant from these solidified products includes a method of baking and a method of treating with a solvent such as water or alcohol.

In the firing method, a temperature of 300 ° C. to 100
The heating is performed in the range of 0 ° C, preferably in the range of 400 ° C to 700 ° C. The heating time should be 30 minutes or more,
In order to completely remove the organic components, it is preferable to heat for 1 hour or more. As the atmosphere, air may be circulated, but since a large amount of combustion gas is generated, an inert gas such as nitrogen may be circulated in the initial stage of combustion.

The method of treating with a solvent or the like is carried out by dispersing a solid product in a solvent having a high solubility for a surfactant, collecting the solid after stirring, and collecting the solid. As the solvent, those having a high solubility in a surfactant, for example,
Water, ethanol, methanol, acetone and the like can be used. In the case of treating with water, it is preferable to carry out the treatment in a range of 25 ° C. or more and 80 ° C. or less. To obtain sufficient solubility, a small amount of a cation component may be added. Substances containing a cation component to be added include hydrochloric acid, acetic acid, sodium chloride, potassium chloride and the like. The concentration of the cation is preferably 0.1 to 10 mol / l. The amount of the solid product dispersed in the ethanol solution is 100
The solid product is preferably 0.5 to 50 g per cc. The dispersion is preferably stirred at a temperature in the range of 25 ° C to 100 ° C. In particular, in the case of a nonionic surfactant, it may be extracted only with a solvent. In addition, by using water to which hydrochloric acid is added or water as a solvent, extraction of the surfactant may be facilitated in some cases. The pulverization, sieving, or molding may be performed before or after removing the surfactant.

Preferred polycondensation methods include a tetra-lower alkoxysilane having 1 to 5 carbon atoms such as tetramethoxysilane and tetraethoxysilane, or (CH ₃ O) ₃ Si—CH ₂ —CH ₂ — Si (OC
_{H 3) 3, (CH 3} O) 3 Si-C 6 H 4 -Si (OC
H ₃ ) _{3 and the} like, and (EO) _x (P
O) 29.67 g of a triblock copolymer represented as _y (EO) _x (where x = 5 to 110, y = 15 to 70, preferably x = 15 to 20, y = 50 to 60)
The polycondensation is carried out at a concentration of not more than 15 g / l, preferably not more than 15 g / l, using water as a solvent and acidifying with hydrochloric acid.

According to such a reaction system, the diffraction angle corresponding to the d value of 1 nm or more in the X-ray diffraction pattern is 1
In the nitrogen adsorption isotherm measured at the liquid nitrogen temperature, the nitrogen adsorption amount when the relative vapor pressure changes by 0.1 in the range of 0.2 to 0.8 in the nitrogen adsorption isotherm (standard The amount of change in the amount of nitrogen adsorbed (converted to the volume of nitrogen in the state) is 50.
A porous body having at least one part / ml or more portion and having mesopores having a central pore diameter of 2 to 50 nm in a pore diameter distribution curve and having a porous pore wall. Can be obtained more reliably.

[Gas Adsorption Separation Method of the Present Invention] Next, the gas adsorption separation method of the present invention will be described.

The gas adsorption / separation method of the present invention may be any method as long as the gas is brought into contact with the porous body using the above-mentioned porous body for gas adsorption / separation of the present invention, whereby specific components in the gas are converted to the porous body. It is adsorbed and separated according to the subsequent holding time. The method of contacting the gas with the porous body at that time is not particularly limited, and for example, the porous body is packed in a column, and the gas containing the gas component to be treated is continuously or intermittently contacted there. A so-called gas chromatography method or the like is employed. When the specific components in the gas are separated by simply adsorbing them on the porous body, the gas containing the gas component to be treated may be brought into contact with the porous body in a batch manner.

The gas components to be treated include exhaust gas, plant gas, reformed gas and hydrocarbons in air (for example, methane, ethane, ethylene, propane, propylene, n-butane, i-butane, hexane, octane). , Benzene, cyclohexane, toluene), CO ₂ , CO,
_{NOx, HC, SOx, H 2} S, methanol, ethanol and the like, preferably at least one gas component selected from the group consisting of CO ₂ and hydrocarbons. The conditions for contacting the gas with the porous material of the present invention are not particularly limited, and a temperature region in which the adsorption and separation can be efficiently performed is appropriately selected according to the combination of the porous material to be used and the target gas component.

[0100]

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to the following examples.

Example 1 As a nonionic surfactant, (EO) ₁₇ (PO) ₅₈ (E
O) A triblock copolymer (hereinafter, simply referred to as P104, manufactured by BASF) represented by a composition formula of ₁₇ was used, and tetraethyl silicate (TEOS) was used as a skeleton component. In the presence of P104, TEOS was hydrolyzed using hydrochloric acid as a catalyst to cause condensation polymerization.

That is, 1.76 g of P104 (0.0
Was dissolved in 105 ml of ion-exchanged water, and 20 ml (0.2 ml) of 12N hydrochloric acid was added to this surfactant solution.
4 mol) (total water amount 6.67 mol, surfactant concentration: 14.67 g / l). In a water bath at 45 ° C., 4.73 g of TEOS (0.021 mol) was added to the mixture at a time, and the mixture was stirred for 8 hours. Furthermore, it was left still in an 80 ° C. oil bath for 8 hours. The generated white precipitate was collected by suction filtration, sufficiently washed with a large amount of ion-exchanged water, and then left overnight in a dryer at 45 ° C. The removal of the surfactant is performed while flowing air (flow rate 0.5 ml / mi).
n), the temperature was raised from room temperature to 550 ° C. over 2 hours, and 55
This was performed by firing at 0 ° C. for 6 hours. As a result, a porous body (powder) of Sample 1 was obtained.

The XRD pattern of Sample 1 in the low-angle region was measured, and the obtained result is shown in FIG. For sample 1,
A strong peak was observed at d = 1.96 and a weak peak was observed on the high angle side. This diffraction pattern is (100) from the low angle side,
Sample 1 which is attributed to the (110) and (120) diffraction planes
Has a hexagonal structure.

Next, a nitrogen adsorption isotherm and a pore distribution curve (by the BJH method) of Sample 1 were obtained, and the obtained results were shown in FIG.
(A) and FIG. 4 (b). Further, the center pore diameter, specific surface area, and total pore volume (relative pressure P / P0 = 0.98 hours) of the mesopores in Sample 1 were determined from the pore distribution curve, and the lattice constant was determined by powder X-ray diffraction. a ₀ (a
₀ = d sought pore wall thickness than the difference between the pore diameter determined by ₁₀₀ × 2 / 1.732) and nitrogen adsorption measurements, the results obtained are shown in Table 1.

Further, the nitrogen adsorption isotherm of the nonporous silica having a specific surface area of 38.7 m ² / g was used as a standard isotherm, and the nitrogen adsorption isotherm of the obtained sample 1 was t-plotted to calculate the micropore volume. did. The data of the standard isotherm is shown in FIG.
FIGS. 6A to 6D show approximate curves applied in each range of the relative pressure at the time of plot conversion.

Using this approximate curve, the nitrogen adsorption isotherm of Sample 1 was t-plotted, and the obtained graph is shown in FIG. From this graph, it was found that Sample 1 had micropores and the total micropore volume was 0.072 ml / g.

Using the t-plot, a pore size distribution curve of the micropores obtained by the MP method was obtained, and the pore size (average pore size) of the micropores obtained from the distribution curve is shown in Table 1.

Further, from the above various analysis data, the ratio of the volume of the micropores to the pores, the total pore volume, the total pore volume excluding the micropores, and the fine pores within a range of ± 40% of the central pore diameter. The pore volume (mesopore volume) and the mesopore volume with respect to the total pore volume excluding the micropores were determined, and the obtained results are shown in Tables 1 and 2. Further, from the nitrogen adsorption isotherm shown in FIG. 4 (a), the nitrogen adsorption amount when the relative vapor pressure changes by 0.1 in the range of 0.2 to 0.8 (to the volume of nitrogen in the standard state). The maximum value of the amount of change in the converted nitrogen adsorption amount was determined, and the obtained results are shown in Table 3.

Examples 2 to 4 The amount of TEOS used was 6.56 g (0.0315 mol, Example 2), 8.75 g (0.042 mol, Example 3),
Porous bodies (powder) of Samples 2, 3 and 4 were obtained in the same manner as in Example 1 except that 11.04 g (0.053 mol, Example 4) was used. The nitrogen adsorption isotherms of Samples 2, 3 and 4 were determined and are shown in FIGS. 8 to 10, respectively. In addition, various analysis data were obtained for Samples 2, 3, and 4 in the same manner as in Example 1, and the obtained results are shown in Tables 1 to 3.

Examples 5 to 6 After the mixture was stirred at 45 ° C. for 8 hours, the mixture was allowed to stand still at 90 ° C.
(Example 5) 100 ° C. (Example 6), TEOS /
Except that the ratio of P104 was set to 120, the porous bodies (powder) of Samples 5 and 6 were obtained in the same manner as in Example 1. Various analysis data were obtained for Samples 5 and 6 in the same manner as in Example 1, and the obtained results are shown in Tables 1 to 3.

[0111]

[Table 1]

[0112]

[Table 2]

[0113]

[Table 3]

As is clear from the results shown in Tables 1 to 3, the porous bodies (samples 1 to 6) obtained in Examples 1 to 6 all had the following conditions: (1) X-ray diffraction pattern Has at least one peak at a diffraction angle corresponding to a d value of 1 nm or more,
(2) In the nitrogen adsorption isotherm measured at the liquid nitrogen temperature, the nitrogen adsorption amount when the relative vapor pressure changes by 0.1 in the range of 0.2 to 0.8 (the volume of nitrogen in the standard state) (3) having mesopores having a central pore diameter of 2 to 50 nm in a pore diameter distribution curve; (4) The average pore diameter is 2 nm
Being porous with micropores less than, (5)
The total volume of the micropores is at least 0.05 ml / g,
(6) It was confirmed that 60% or more of the total pore volume excluding micropores was contained within the range of ± 40% of the center pore diameter, and that all of them were satisfied.

Further, from the results shown in Tables 1 to 3, when the concentration of the surfactant is equal to or less than a certain concentration, the molar ratio of the skeleton component / the surfactant is increased to increase the micropore volume,
It was confirmed that the pore diameter and pore volume can be controlled.

Comparative Example 1 In the same manner as in Example 1 except that 3.56 g of P104 (surfactant concentration of 29.67 g / l) was used to confirm that the formation of micropores was closely related to the surfactant concentration. Thus, a porous body (powder) as Comparative Sample 1 was obtained. This sample had a hexagonal structure by powder X-ray diffraction, and its nitrogen adsorption isotherm was as shown in FIG.
In addition, the adsorption isotherm of Comparative Sample 1 matched the standard curve as shown in FIG. 12, and the presence of micropores was not recognized.

Comparative Example 2 After the mixture was stirred at 45 ° C. for 8 hours, the mixture was allowed to stand at 100 ° C.
° C and the ratio of TEOS / P104 was 60, and a porous body (powder) of Comparative Sample 2 was obtained in the same manner as in Example 1. In Comparative Sample 2, the presence of micropores was not recognized.

Examples 7 to 8 The amounts of the respective raw materials used are as follows: (Example 7) P104 17.2 g Ion-exchanged water 1060 mL 12N aqueous hydrochloric acid 200 mL TEOS 87.8 g (Example 8) P104 34.4 g Ion-exchanged water 1060 mL The porous bodies of samples a and b were obtained in the same manner as in Example 1 except that the amount of 12N hydrochloric acid aqueous solution was 200 mL and TEOS was 87.8 g.

Next, 30 g of the obtained mesoporous materials of the samples a and b were dispersed in 100 mL of a 10% (v / v) aqueous methanol solution, stirred for 1 minute, and the precipitate was collected by suction filtration. The collected precipitate is dried in a dryer at 45 ° C., and then pressed at a pressure of 500 kgf / cm ² ,
By firing at 550 ° C. for 6 hours in an oxygen atmosphere, the surfactant as a mold was removed. Each of the calcined samples was pulverized in a mortar, and the particles of the powder were adjusted from 150 μm to 300 μm by a sieve to obtain a column packing for gas molecule separation. Comparative Example 3 FSM-16 was used as a mesoporous material for comparison in which micropores did not exist in the pore wall. The synthesis of FSM-16 was performed according to an external report. Hereinafter, the procedure will be described.

Sodium disilicate (δ-Na ₂ Si ₂ O ₅ )
50.0 g was dispersed in 500 mL of ion-exchanged water, stirred at room temperature for 3 hours, and then the precipitate was collected by suction filtration. This precipitate was dispersed in an aqueous solution obtained by dissolving 32.0 g of hexadecyltrimethylammonium chloride in 1 liter of ion-exchanged water, stirred in a 70 ° C. water bath for 3 hours, and adjusted to pH 8. using a 2N aqueous hydrochloric acid solution. 5 was prepared.
Then, after stirring in a 70 ° C. water bath for 3 hours, a white precipitate was obtained. The obtained white precipitate was collected by suction filtration, washed sufficiently with a large amount of ion-exchanged water, and left standing in a drier at 45 ° C. for drying to obtain a porous material of sample c.

Next, sample c (FSM-16) was added to 500
After pressing at a pressure of kgf / cm ² , 550 ° C. in an oxygen atmosphere
For 6 hours to remove the surfactant as a mold. The calcined sample was pulverized with a mortar, and the particles of the powder were adjusted from 150 μm to 300 μm with a sieve,
It was used as a column packing for gas molecule separation.

[Analysis of Physical Properties and the Like] The powder X-ray diffraction (XRD) and the adsorption isotherm of the samples (fillers) a, b and c obtained in Examples 7 and 8 and Comparative Example 3 were the same as those in Example 1. The obtained powder X-ray diffraction (XRD) and adsorption isotherm are shown in FIGS. 13 and 14, respectively. Sample a,
Various analysis data were obtained for b and c in the same manner as in Example 1,
The obtained results are shown in Tables 4 to 6.

As is evident from the results of the powder X-ray diffraction (XRD) shown in FIG.
A strong peak near ゜ and several weak peaks on the wide-angle side were observed, confirming that a regular mesostructure was formed. Also, from the observed XRD pattern, sample a,
b and c respectively form a two-dimensional hexagonal skeleton structure, and each peak is (100), (11) from the base angle side.
0) and (200).

Further, the adsorption isotherm shown in FIG.
As is clear from the data shown in FIGS.
110 ml / g, sample b had a micropore volume of 0.051 ml / g, whereas sample c did not show the presence of micropores. Furthermore, it was confirmed that all of the porous bodies (samples a and b) obtained in Examples 7 and 8 satisfied all of the above-described conditions (1) to (6).

[0125]

[Table 4]

[0126]

[Table 5]

[0127]

[Table 6]

[Gas Component Adsorption Separation Test] Examples 7 and 8
Using the samples (column packings for gas separation) a, b, and c obtained in Comparative Example 3, the retention times of various gas molecules were measured by gas chromatography (GC) under the following conditions, respectively. The adsorption and separation characteristics for gas molecules were evaluated. As a pretreatment of the filler before measurement, 15
Helium as a carrier gas was flowed at 0 ° C. at a flow rate of 40 mL / min for 6 hours to dry the filler. The GC measurement conditions are as follows.

Column Glass column (2 m) Carrier gas Helium (40 mL / min) INJ temperature 50 ° C. TCD temperature 80 ° C. Column temperature 50 ° C. Gas using these samples (column packing for gas separation) a, b, c Table 7 shows the results of the molecular adsorption / separation evaluation (retention time measurement). The gas molecules used here are hydrogen (H ₂ ), carbon monoxide (CO), nitrogen (N ₂ ), oxygen (O ₂ ), nitric oxide (NO) as an acid gas, and carbon dioxide (CO 2). ₂ ), methane (C
H _4), ethane (C ₂ H _6), propane (C ₃ H _8), n- butane (nC ₄ H _10), i- butane (iC ₄ H _10), ethylene (CH
₂ = CH ₂ ) and propylene (CH ₂ = CHCH ₃ ) were used.

[0130]

[Table 7]

As is clear from the results shown in Table 7, the samples obtained in Examples 7 and 8 (gas separation column packing material)
According to a and b, the retention time of a specific gas component is much longer than that of the sample c obtained in Comparative Example 3 having no micropores. In particular, hydrocarbon gas such as CO, CO ₂ and propylene is It was confirmed that adsorption and separation can be performed efficiently and selectively with respect to other gases. In addition,
It was also confirmed that the tendency for the retention time to be longer for a particular gas component tended to increase in proportion to the micropore volume present within the pore walls.

Comparative Examples 4 and 5 For comparison, MS-3A zeolite (Comparative Example 4) and U
Using SY-type zeolite (Comparative Example 5), the retention time for nitric oxide (NO), carbon dioxide (CO ₂ ), and propylene (C ₃ H ₆ ) was measured in the same manner as in the above-mentioned adsorption separation test for gas components. did. Table 8 shows the obtained results.

[0133]

[Table 8]

The results shown in Tables 7 and 8 clearly show the results.
According to the samples a and b of Examples 7 and 8 according to the present invention,
For example, compared to using a conventional zeolite, carbon dioxide
(CO _Two), Propylene (C_ThreeH₆) When holding
It was confirmed that the interval was approximately doubled.

[0135]

As described above, the gas adsorption of the present invention
Separation porous body, and gas adsorption component of the present invention using the same
According to the separation method, specific components in the gas, for example, hydrocarbons
And CO _TwoEtc. can be selectively and efficiently adsorbed and separated.
It becomes possible.

Therefore, the porous body for gas adsorption separation of the present invention adsorbs hydrocarbons in the exhaust gas at the time of engine start (cold start) temporarily, and when the catalyst warms up to the temperature at which the catalyst becomes active, the carbonaceous substance is removed. and adsorbent to release hydrogen, hydrocarbon modified sorbent and to remove the CO and CO ₂ as an impurity in the hydrogen produced by the CO ₂ in the process gas of the fuel-gas and chemical plants It is very effective as an adsorbent for an apparatus for separating and recovering by the pressure swing method (PSA method) or an adsorbent for a solvent recovery apparatus.

[Brief description of the drawings]

FIG. 1 is a graph showing slopes representing the slopes of each t value section in a plot of pore volume (V) and thickness (t).

FIG. 2 is a graph showing a distribution curve of micropores created based on FIG.

FIG. 3 is a graph showing an XRD pattern of Sample 1.

4A is a graph showing a nitrogen adsorption isotherm, and FIG. 4B is a graph showing a pore distribution curve obtained by a BJH method.

FIG. 5 is a diagram showing data of a standard isotherm.

FIGS. 6A to 6D are graphs each showing an approximate curve obtained based on a standard isotherm.

FIG. 7 is a graph in which a nitrogen adsorption isotherm of Sample 1 is t-plotted.

FIG. 8 is a graph showing a nitrogen adsorption isotherm of Sample 2.

FIG. 9 is a graph showing a nitrogen adsorption isotherm of Sample 3.

FIG. 10 is a graph showing a nitrogen adsorption isotherm of Sample 4.

FIG. 11 is a graph showing a nitrogen adsorption isotherm of a comparative sample.

FIG. 12 is a graph obtained by t-plotting a nitrogen adsorption isotherm of a comparative sample.

FIG. 13 is a graph showing XRD patterns of samples a, b, and c.

FIG. 14 is a graph showing nitrogen adsorption isotherms of samples a, b, and c.

Claims (7)

[Claims] 1. An X-ray diffraction pattern having one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more, and having a relative vapor pressure of 0.2 in a nitrogen adsorption isotherm measured at a liquid nitrogen temperature. The relative vapor pressure is 0.1
A porous body having at least one or more portions where the amount of change in the amount of nitrogen adsorbed (the amount of nitrogen adsorbed in terms of the volume of nitrogen in a standard state) at the time of change is 50 ml / g or more. A porous body for gas adsorption separation having mesopores having a pore diameter of 2 to 50 nm and a porous pore wall. 2. The method according to claim 1, wherein the pore walls are porous having micropores having an average pore diameter of less than 2 nm, and the total volume of the micropores is 0.05 ml / g or more. The porous body for gas adsorption separation according to the above. 3. The porosity for gas adsorption separation according to claim 2, wherein 60% or more of the total pore volume excluding the micropores is contained within a range of ± 40% of the central pore diameter. body. 4. An X-ray diffraction pattern having one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more, and having a relative vapor pressure of 0.2 in a nitrogen adsorption isotherm measured at a liquid nitrogen temperature. The relative vapor pressure is 0.1
A porous body having at least one or more portions where the amount of change in the amount of nitrogen adsorbed (the amount of nitrogen adsorbed in terms of the volume of nitrogen in a standard state) at the time of change is 50 ml / g or more. A gas adsorption separation method comprising: adsorbing and separating components in a gas by bringing a gas into contact with a porous body having mesopores having a pore diameter of 2 to 50 nm and a porous wall being porous. 5. The method according to claim 4, wherein the pore wall is porous having micropores having an average pore diameter of less than 2 nm, and the total volume of the micropores is 0.05 ml / g or more. The gas adsorption separation method according to the above. 6. The gas adsorption separation method according to claim 5, wherein the range of ± 40% of the central pore diameter includes 60% or more of the total pore volume excluding the micropores. 7. The method according to claim 4, wherein the component in the gas is at least one component selected from the group consisting of carbon dioxide and hydrocarbons. Gas adsorption separation method.