JPH04280810A - Production of molecular sieve carbon - Google Patents

Abstract

PURPOSE:To produce a new and simple molecular sieve carbon having excellent separation performance. CONSTITUTION:At least one kind of resin powder selected from a group of phenolic resin powder, melamine resin powder or modified resin powders therefrom is mixed with at least one kind of binder component selected from coal tar, pitch and creosote oil and the mixture is formed into granular articles and these articles are carbonized.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for producing molecular sieve carbon, and more specifically, the present invention relates to a method for producing molecular sieve carbon, and more specifically, the molecular sieve carbon is applied to fields such as separation and purification of mixed gases due to the molecular sieving effect of fine pores. Regarding manufacturing methods.

0002

BACKGROUND OF THE INVENTION Molecular sieves made from non-polar and hydrophobic carbon are attracting attention as molecular sieves that have excellent heat resistance and chemical resistance and can be used even in the presence of polar substances.

Conventionally, this molecular sieve carbon has been produced by using natural raw materials as starting materials and controlling the micropore shape of the carbon surface through complicated processes (Japanese Patent Publication No. 52-1
Publication No. 8675). On the other hand, JP-A-64-6130
No. 6 discloses that molecular sieve carbon with excellent homogeneity can be produced using a synthetic polymer as the main raw material through a simpler process.

It has been disclosed that the molecular sieve carbon produced by the above method is effective for separating various mixed gases, particularly for separating nitrogen and oxygen in the air.

[0005] Particularly, PS that separates nitrogen gas from air using molecular sieve carbon produced by the above-mentioned production method.
Type A nitrogen gas generators are rapidly becoming popular in recent years as a simple and inexpensive method of supplying nitrogen gas.

[0006] However, the nitrogen gas obtained by a PSA nitrogen gas generator usually has a purity of about 99 to 99.9%, and the high purity nitrogen obtained by cryogenic separation method (99.99%
9% or more), the quality is currently inferior. Therefore, the 9
A method has been adopted in which nitrogen gas with a purity of about 9 to 99.9% is further improved in purity using a purification device, but this method is unavoidably disadvantageous in terms of economic efficiency due to the high purification cost. .

[0007] In order to obtain high-purity nitrogen gas using only a PSA nitrogen gas generator without using purification equipment, it is essential to develop a higher performance molecular sieve carbon, and a new method for producing molecular sieve carbon is needed. It is hoped that it will be provided.

[0008]

[Problems to be Solved by the Invention] The present inventors have completed the present invention as a result of intensive research to solve the above problems. The object of the present invention is to provide a new and simple method for producing high-performance carbon molecular sieves.

[0009]

[Means for Solving the Problems] The above object is to combine at least one resin powder selected from the group consisting of phenolic resin powder, melamine resin powder, or modified resin powder thereof, and coal tar, pitch, and creosote oil. This is achieved by a method for producing molecular sieve carbon, which is characterized by mixing at least one selected binder component, forming into granules, and then carbonizing.

[0010] In the present invention, phenol resin powder, melamine resin powder, or one or more resin powders selected from modified resins thereof are used as the raw material component.

[0011] Phenol resins can be broadly classified into resol resins and novolac resins, and there are also special phenol resins and modified products. Resole resins are usually prepared in excess of formaldehyde, such as at a molar ratio of phenol to formaldehyde of 1:1 to 2, in the presence of a basic catalyst (about 0.2 to 2%), such as sodium hydroxide, ammonia, or an organic amine. It is produced by reacting under certain conditions. The resol resin thus obtained is mainly composed of mono- to trimer of phenol having a relatively large amount of free methylol groups, and has high reactivity.

[0012] In addition, the novolak resin usually has a molar ratio of phenol to formaldehyde of, for example, 1:0.7 to 0.
．． It is produced by reacting phenol and formalin in the presence of an acid catalyst such as oxalic acid (usually 0.2 to 2%) under conditions where the amount of phenol is in excess such that the amount of phenol is 9.

[0013] The novolak resin obtained by this method is
3 in which phenol is linked primarily by methylene groups
-5mer is the main component, contains almost no free methylol groups, and therefore does not have self-crosslinking property by itself and has thermoplasticity.

[0014] Therefore, the novolac resin is prepared by adding a crosslinking agent such as hexamethylenetetramine, which itself is both a formaldehyde generator and an organic base (catalyst) generator, or by mixing a solid acid catalyst with paraformaldehyde, etc. A cured product can be obtained by reacting under heating.

In addition, in recent years, a method has been developed in which a hydrophilic polymer compound is added to a condensate obtained by reacting phenols and formaldehyde in the presence of at least a nitrogen-containing compound (Japanese Patent Publication No. 53-12958). Publication No.)
A powdered resin is produced by a method such as mixing a prepolymer obtained by reacting phenol and formaldehyde in a basic aqueous solution with a protective colloid and coagulating it into an inert solid bead shape under acidic conditions (Japanese Patent Publication No. 13491/1983). It is now possible to manufacture.

Furthermore, granular or powdered phenol formaldehyde resins are disclosed in, for example, Japanese Patent Application Laid-Open No. 57-1770.
It can also be produced by the production methods disclosed in Japanese Patent Application Laid-open No. 11, No. 17114/1980, and the like. The outline is as follows. At room temperature, with 15-22% by weight hydrochloric acid and 7-15%
While stirring a mixed aqueous solution consisting of % formaldehyde, phenol or a mixture of phenol and a nitrogen-containing compound such as urea, melamine, aniline, etc. is added at a ratio of 1/15 or less to the mixed aqueous solution, and the reaction is carried out. Stop stirring and leave the system stationary before cloudiness forms in the system. While the reaction system was left standing, pink granular phenol resin was formed and precipitated.

Next, the entire reaction system was stirred again for 40 minutes.
After heating and raising the temperature to a temperature of ~90°C to complete the reaction, it was washed with water, and then neutralized with an ammonia aqueous solution.
Wash, dehydrate, and dry. The granular phenol resin is mostly composed of primary particles or secondary aggregates thereof with a particle size of 0.1 to 150 μm. In addition, phenolic resin powder is disclosed in Japanese Patent Application Laid-open No. 61-51019 and Japanese Patent Application Laid-open No. 61-127719.
No. 61-258819, JP-A-62
It can be produced by the methods described in Japanese Patent Application Laid-Open No. 172-27260, Japanese Patent Application Laid-Open No. 1748-1980, and the like.

The phenol resin powder used in the present invention may be any phenol resin powder produced by the above-mentioned methods or other known methods, and there are no particular limitations on the production method, particle shape, etc. Not, but
Preferably, phenol resin powder manufactured by the manufacturing method disclosed in JP-A-57-177011 and JP-A-58-17114 may be used. Melamine resin is a so-called thermosetting resin, and the chemical reaction is accelerated by heating, and it becomes in the form of a hydrophilic initial condensate or a slightly condensed hydrophobic condensate, and finally becomes insoluble and infusible. Become a thing.

[0019] Melamine resin contains melamine, aldehyde,
It is usually produced by adding formaldehyde. Also, various alcohols may be used simultaneously. The production of melamine resin involves a reaction in which formaldehyde is first added to melamine as a methylol group, and then the methylol group is dehydrated and condensed with amino groups or imino groups of other molecules to form methylene groups, or the methylol groups are combined with each other. The reaction proceeds by dehydration condensation to form a dimethylene ether bond, or by dehydration and etherification between a methylol group and an alcohol. Melamine resins can be divided into water-soluble resins and oil-soluble resins, and generally water-soluble resins are manufactured using methanol as alcohol. On the other hand, oil-soluble resins are also called butylated melamine resins, and butanol is usually used as the alcohol.

The melamine resin used in the present invention may be either water-soluble or oil-soluble, and may be produced by known methods. The particle shape and particle size of the phenol resin powder, melamine resin powder, or their modified resin powder used in the present invention are not particularly limited, but preferably have a particle diameter of 1 to 100 μm, more preferably a particle diameter of about 3 to 30 μm. be. In the present invention, one or more components selected from coal tar, pitch, and creosote oil are used as the binder component.

Coal tar is a mixture of compounds mainly consisting of hydrocarbons obtained by carbonization of coal, and contains a small amount of water and a small amount of ash. Although these compositional ratios and physicochemical properties vary depending on the type of raw coal, type of carbonization furnace, carbonization conditions, etc., the currently known components are 40%.
There are 0 or more types of components, and among these, the most common are neutral components such as benzene, toluene, and anthracene, followed by basic components such as pyridine, aniline, and quinoline, and furthermore phenol, cresol, naphthol, and anthranol. oxygen-containing components such as benzofuran, diphenylene oxide, and p-methoxybenzophenone; and sulfur-containing components such as benzothiophene, diphenylene sulfide, and naphthothiophene. The coal tar used in the present invention is not particularly limited in terms of the above-mentioned components, but one containing a large amount of condensed ring aromatic compounds is more suitable.

Pitch is chemically a mixture of mainly condensed ring aromatic compounds, is viscous, and is usually in the form of a solid or a solid at room temperature. Classified by raw materials, there are a wide variety of pitches, including coal-based pitch, petroleum-based pitch, pitch obtained during carbonization of wood, pitch obtained from oil sand, oil shur, etc.

Coal-based pitch is obtained as a residue by distilling coal tar produced by carbonization of coal to remove oil, and is a mixture of many high-boiling substances with a boiling point of about 350°C or higher and free carbon. It is. Petroleum-based pitch is produced by heat-treating heavy petroleum oils such as vacuum distillation residues of crude oil, crude oil pyrolysis residues, and cracking residues from fluid catalytic crackers for the purpose of producing gasoline. It is obtained as a component through thermal polycondensation together with decomposition products such as extracted oil.

Furthermore, pitch is classified into three types depending on the degree of softness or hardness: soft pitch, medium pitch, and hard pitch. Usually, depending on the softening point (ring and ball method), below about 70℃ is soft pitch, about 70℃ to 85℃ is medium pitch, and about 85℃
The above pitches are classified as hard pitches. The pitch used in the present invention may be any pitch such as coal-based pitch or petroleum-based pitch, and its properties such as softening point are not particularly limited.

[0025] Creosote oil is produced by mixing the residual oil obtained by separating and recovering components from each fraction of coal tar oil according to specifications. According to JIS standards, specific gravity, moisture content,
They are classified into Nos. 1 to 3 based on distillation test results and other factors. Creosote oil is usually chemically a mixture of dozens or more types of fused ring aromatic compounds, and the main components are naphthalene, anthracene, phenanthrene, pyrene, biphenyl, fluorene, cresol, 1-methylnaphthalene,
These include methylnaphthalene, dimethylfluorene, and various derivatives of these compounds, and most of them have a boiling point of 200°C or higher.

[0026] The creosote oil used in the present invention is
Any of No. 1, 2, or 3 according to the standard may be used, and there is no particular restriction, but according to the results of a distillation test, 360 ° C.
No. 3, which has a distillation amount of 60 v/v% or more, is preferably used. Now, in the present invention, one or more resin powders selected from the above-mentioned phenol resin powder, melamine resin powder, or modified resin powder thereof, and one or more resin powders selected from coal tar, pitch, and creosote oil are used. Two or more types of binder components are mixed to obtain a granular molded product.

The resin powder and the binder component may be mixed at room temperature or under heating using a commercially available mixer such as a kneader. When coal tar or pitch is used as a binder component, its workability is considered and the mixture is heated to a temperature at which sufficient fluidity occurs. Further, in order to improve workability, an appropriate amount of water or an organic solvent such as methanol or acetone may be added. Creosote oil is usually liquid at room temperature, and has good workability during mixing even at room temperature.

In the present invention, the mixing ratio of the resin powder and the binder component is not particularly limited;
Considering the workability during mixing, the strength of the granular compact, the physical properties of the molecular sieve carbon after carbonization, etc., phenolic resin powder,
1 to 50 parts by weight of one or more binder components selected from coal tar, pitch, and creosote oil per 100 parts by weight of one or more resin powders selected from melamine resin powder or modified resin powder thereof. Parts by weight, preferably 2 to 35 parts by weight, most preferably 3 to 30 parts by weight
Parts by weight. The present invention does not limit the addition of other additive components in addition to the resin powder and binder component, such as liquid phenol resin, liquid melamine resin, polyvinyl alcohol, starch, crystalline cellulose powder, Appropriate amounts of methylcellulose, water, solvent, etc. can be added.

[0029] Furthermore, there is no restriction at all in adding a small amount of coal, coke, coconut shell charcoal, etc. Furthermore, in the present invention, in order to improve workability during mixing and granulation without impairing the properties, interfaces such as ethylene glycol, polyoxyethylene, alkyl ether, polyoxyethylene fatty acid ester, polycarboxylic acid ammonium salt, etc. A small amount of an activator, a hardening agent for liquid thermosetting resin, a crosslinking agent for polyvinyl alcohol, a plasticizer for extrusion granulation, etc. can be added.

The raw material components of the present invention are uniformly mixed by a mixing device and then formed into granules. Molding into granules can be carried out using, for example, a single-screw or twin-screw wet extrusion granulator, a rigid granulator such as a basket leuther, a semi-dry disc pelleter, or the like. This molding is usually carried out at room temperature, but may be carried out under heating if the pitch component is large. The shape of the granules is, for example, cylindrical or spherical. The size of the granules obtained by granulation is not particularly limited, but for example, a cylinder has a diameter of 0.5 to 5.
mm, the length is about 1 to 10 mm, and the diameter is 0.0 mm if it is spherical.
Approximately 5 to 10 mm is preferable. The granular compact obtained as described above is carbonized in a temperature range of 500 to 1100°C in a non-oxidizing atmosphere, or after carbonization, one part of the carbide is
Molecular sieve carbon can be obtained by performing activation within a range where the weight decreases within 5% by weight. The carbonization and activation temperature is preferably 600-1000°C, most preferably 650°C.
~950°C. In this case, the non-oxidizing atmosphere is, for example, an atmosphere of nitrogen, argon, helium, or the like. The temperature increase rate until reaching the maximum treatment temperature in the carbonization step is not particularly limited, but is preferably 5 to 500°C/H.
It is. In addition, the oxidizing atmosphere during activation includes, for example, air,
Steam, carbon dioxide gas, etc. can be used.

By the way, the molecular sieve effect of molecular sieve carbon is such that the pore diameter of the micropores is in the range of several angstroms, which is extremely close to the molecular diameter of the adsorbed molecules, and exhibits selective adsorption characteristics for various substances with different molecular diameters. This is due to a number of reasons. Therefore, the performance of molecular sieve carbon is determined by the pore size distribution of the micropores, and the pore diameter is usually 10 Å or less, preferably 3 to 3.
Carbon sieves having a sharp distribution in a range of approximately 5 Å are preferred as molecular sieve carbons. The pore size distribution determined from the nitrogen gas adsorption isotherm of the carbon molecular sieve of the present invention has a maximum value of the pore size distribution of micropores in the region of diameters of 10 Å or less, preferably 3 to 5 Å, and pores of 10 Å or less The volume is preferably 0.1 to 0.7 cc/g, more preferably 0.15
~0.5cc/g.

The specific surface area of the molecular sieve carbon having the above-mentioned pore structure is determined by B. E. As a result of measurement by T method, it is usually 1 to 600 m2/g, preferably 10 to 50 m2/g.
0m2/g, most preferably 50-350m2/g
That's about it. Further, the particle bulk density of the molecular sieve carbon of the present invention is preferably 0.1 to 1.2 g/cm3, the porosity is preferably 25 to 50%, and the carbon content is preferably 90%.
% by weight or more.

[0033]

Effects of the Invention The molecular sieve carbon of the present invention can be produced by the simple method described above, and has excellent adsorption capacity and selective adsorption properties. Therefore, the molecular sieve carbon of the present invention can be used to separate various mixed gases. For example, gaseous mixtures of nitrogen gas and oxygen gas, gaseous mixtures of methane gas and hydrogen gas, hydrocarbon isomer mixtures such as xylene isomers, butane isomers, butene isomers,
It can be used to separate mixtures of ethylene and propylene, gas mixtures containing argon, etc.

More specifically, for example, it is used to obtain nitrogen gas, oxygen gas, or a gas mixture enriched in either nitrogen gas or oxygen gas from a gas mixture containing nitrogen gas and oxygen gas. be able to. or,
It can be used to obtain a gas mixture enriched with methane gas, hydrogen gas, or either methane gas and hydrogen gas from a gas mixture containing methane gas and hydrogen gas. For this purpose, it is desirable to employ a pressure swing adsorption method.

In the pressure swing adsorption method, two or three adsorption towers are usually filled with molecular sieve carbon, and 3 to 7 kgf
The mixed gas can be separated by periodically repeating selective adsorption under a pressure of about /cm2 and regeneration of the adsorbent under reduced pressure or normal pressure. In addition to the above-mentioned mixed gas separation, this method can also be used to recover hydrogen from steam reforming gas, ethylene plant off-gas, methanol cracked gas, ammonia cracked gas, coke oven exhaust gas, etc., and carbon monoxide from converter exhaust gas. It can be implemented. The present invention will be specifically explained below with reference to Examples.

Example 1 300 kg of a mixed aqueous solution consisting of 18% hydrochloric acid and 9% formaldehyde was placed in a 400 liter reaction vessel, and the temperature was adjusted to 20°C. Next, a concentration of 98% (2
% is water) concentration adjusted using phenol and water 90
% phenol aqueous solution (20°C) was added. After the addition, the mixture was stirred for 30 to 40 seconds, and at the same time the contents in the reaction vessel suddenly became cloudy, stirring was stopped and the mixture was allowed to stand still. As the contents were left to stand still, the internal temperature gradually rose, and the contents gradually turned pale pink, and 30 minutes after the contents became cloudy, a slurry-like product was observed.

Subsequently, the contents were heated to 75-76°C for 30 minutes.
The temperature was raised in 1 minute, and maintained at this temperature for 40 minutes while stirring. Next, the contents were washed with water, neutralized with an ammonia aqueous solution with a concentration of 0.1% at 50°C for 6 hours, filtered with an aqueous solution, dried at 80°C for 6 hours, and phenol with an average particle size of 28 μm was prepared. A resin powder was obtained. In addition, melamine resin powder is a melamine resin aqueous solution (Sumitomo Chemical Co., Ltd.)
After thermally curing Sumitex Resin M-3) manufactured by Sumitex Co., Ltd., it was pulverized using a pulverizer to prepare a powder having an average particle size of 12 μm.

[0038] As binder components, coal tar (JIS standard, K2439-1979, refined tar No. 2), pitch (softening point 80°C, ash content 0.4% or less), creosote oil (JIS standard, K2439-1979, No. 3) was prepared. Furthermore, as other additives, a 15% by weight aqueous solution of polyvinyl alcohol (degree of polymerization 1700, degree of saponification 99%) and potato starch were prepared. The above raw materials were mixed in a kneader for 15 minutes at the mixing ratio shown in Table 1, and then extruded using a twin-screw extrusion granulator to obtain an average particle size of 3 mmφ×
A cylindrical pellet of 6 mmL was produced. After curing and drying the pellets of each composition at 90°C for 24 hours, they were placed in a rotary kiln with an effective diameter of 600φ x 2000mmL, and heated to 800°C at 30°C/H under a nitrogen stream.
The temperature was raised to 100.degree. C., maintained at this temperature for 1 hour, and then cooled in the furnace.

In order to evaluate the molecular sieving properties of the granular carbide thus obtained, the amounts of nitrogen gas and oxygen gas adsorbed were measured using the adsorption property measuring device shown in FIG. In the same figure, 3g of sample is put into sample chamber (4) (200ml), valves (11) and (8) are closed, and valves (2) and (3
) was opened and deaerated for 30 minutes, then valves (2) and (3) were closed, valve (11) was opened, and oxygen or nitrogen gas was sent into the adjustment chamber 5 (200 ml), and the set pressure (6.0
When it reaches 0kgf/cm2), turn off the valve (11).
was closed, the valve (3) was opened, and the change in internal pressure over a predetermined period of time was measured to determine the adsorption rate of each of oxygen and nitrogen.

Note that (1) is a vacuum pump, (6), (7
) is the pressure sensor, (9), (12) is the recorder, (10
) is a pressure gauge, (14) and (15) are gas regulators, (16) is a nitrogen cylinder, and (17) is an oxygen cylinder. As an index showing the separation performance of nitrogen and oxygen, the adsorption amount 1 minute after the start of adsorption is taken as Q1 for nitrogen and Q2 for oxygen, and the difference in adsorption amount ΔQ is calculated using the following formula (I) ΔQ=Q2 −Q1 ...(I ), and the selection coefficient α is determined by the following formula (I
I). The results are shown in Tables 1-4.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

[Table 3]

[0044]

[Table 4]

As shown in Tables 1 to 4, sample No. 1 contains no binder components (coal tar, pitch, creosote oil). Sample No. 1 shows a certain degree of molecular sieving performance, but when compared to the binder component-containing samples (No. 2 to No. 8), both the adsorption amount difference and the selection coefficient are small, and there is a noticeable difference in the molecular sieving performance. In addition, sample No. No. 9 has too much binder component, so the oxygen adsorption capacity is low and it is not practical.

Example 2 Using sample 5 of Example 1, pressure swing adsorption (PSA) was performed.
An experiment was conducted to separate nitrogen and oxygen in the air using the method. A schematic diagram of the PSA composition used in this experiment is shown in FIG. 2. The size of the adsorption towers was 50φ in inner diameter x 1000 mmL, and the two adsorption towers were filled with molecular sieve carbon. Sample No. 5
The packing density was 0.665 g/cm3. First, air compressed by a compressor was sent to the adsorption column, and the pressure in the adsorption column was set to 7 kgf/cm2.G in gauge pressure, and desorption and regeneration was carried out by returning the adsorption column to normal pressure. P.S.
Operation A was performed in four steps: pressure equalization (pressurization) - adsorption - pressure equalization (depressurization) - exhaust, and switching between each step was performed by automatically controlling a solenoid valve with a sequencer. Table 5 shows the PSA operating conditions.
Shown below.

In this experiment, the amount of product nitrogen gas taken out was 1 liter.
Nitrogen purity (N2 + Ar, vol%) 99./min.
9991%, 99.993% at withdrawal rate 1.5l/min
Met.

[0048]

[Table 5]

Comparative Example 1 Sample No. of Example 1. An experiment similar to Example 2 was conducted using Sample No. 1 (the adsorption packing density of Sample No. 1 was 0.661
g/cm3). As a result, the product gas extraction amount was 1l/mi.
Nitrogen purity 99.7% at n, 99.4 at 1.5l/min
%, the performance was significantly inferior to that of Example 2.

Comparative Example 2 Sample No. 1 of Example 1. An experiment similar to that in Example 2 was conducted using Example 9. Sample No. The packing density of 9 is 0.658g/c
It was m3. As a result, the product gas extraction amount was 1l/mi.
Nitrogen purity 96.5% at n, 95.4 at 1.5l/min
%, the separation performance was significantly inferior.

Example 3 24 kg of phenol and 56 kg of novolac resin were placed in a 400 liter reaction vessel and heated to 50°C with stirring to dissolve the novolak resin in the phenol. Next, 24 kg of 37% formalin, 56 kg of water, and 2 kg of hexamethylenetetramine.
．． 2 kg of calcium chloride, 3.4 kg of potassium fluoride, and 2.3 kg of potassium fluoride were added, and the temperature was raised to 90°C.
The reaction was carried out for 0 minutes to obtain an emulsion of microspherical hardened phenol resin. This was cooled to 40° C., 200 liters of water was added and the supernatant liquid was removed, and the microspheroidal resin particles in the lower layer were washed with water and air-dried. This was further dried at 50 to 60°C to obtain a phenol resin powder with an average particle size of about 20 μm.

As resin powders, the above phenol resin powder and melamine resin powder with an average particle size of 7 μm produced in the same manner as in Example 1 were prepared, and pitch (softening point: 80° C., ash content: 0.4%) was prepared as a binder component. (below) and creosote oil (JIS standard K2439, No. 3) were prepared. Furthermore, as other additives, a melamine resin aqueous solution (Sumitex Resin M3, manufactured by Sumitomo Chemical Co., Ltd.), a 10% by weight aqueous solution of polyvinyl alcohol (degree of polymerization 1700, degree of saponification 99%), and ethylene glycol were prepared.

[0053] The above raw materials were mixed and extruded into granules in the same manner as in Example 1 in the proportions shown in Tables 6 to 9, and the average particle diameter was 3 mmφ×
A cylindrical pellet of 6 mmL was obtained. Each pellet is
After curing and drying each at 85°C for 24 hours, they were placed in a rotary kiln with an effective diameter of 600φ x 2000mmL, heated to 900°C at a rate of 60°C/H under a nitrogen stream, kept at that temperature for 30 minutes, and then cooled in the furnace. did. The oxygen and nitrogen adsorption capacity of the granular carbide thus obtained was measured in the same manner as in Example 1. The results are shown in Tables 6-9.

[0054]

[Table 6]

[0055]

[Table 7]

[0056]

[Table 8]

[0057]

[Table 9]

As shown in Tables 6 to 9, sample No. 1 contains no binder components (coal tar, pitch, creosote oil). Sample No. 10 shows a certain degree of molecular sieving performance, but when compared to the binder component-containing samples (Nos. 11 to 18), both the adsorption amount difference and the selection coefficient are small, and the molecular sieving performance is low. Also, sample No. No. 19 has too much binder component, so its oxygen adsorption capacity is low and it is not practical.

Example 4 Sample No. 3 of Example 3. In exactly the same manner as in Example 2, an experiment was carried out to separate nitrogen and oxygen in the air using PSA No. 14. Sample No. The packing density of 14 is 0.668g
/cm3. In this experiment, the amount of product nitrogen gas taken out was 1 liter/min, and the nitrogen purity (N2 + Arvol%) was
99.9993%, 99.9 at withdrawal rate 1.5l/min
It was 94%.

Sample No. 3 of Example 3 An experiment similar to Example 4 was conducted using Sample No. 10 (packing density of sample No. 10 was 0.663 g/cm3). As a result, the nitrogen purity was 99.3% at a product nitrogen gas extraction rate of 1 liter/min, 1.5 liter/min.
The min value was 99.1%, and the performance was significantly inferior to that of Example 4.

Comparative Example 4 Sample No. 4 of Example 4. An experiment similar to Example 4 was conducted using Sample No. 19 (the packing density of Sample No. 19 was 0.660
g/cm3). As a result, the amount of product nitrogen gas taken out was 1 liter/
Nitrogen purity 97.0% at min, 97 at 1.5l/min
．． At 8%, the separation performance was extremely poor.

Example 5 Sample No. of Example 1. 60 cylindrical pellets with an average particle diameter of 3 mmφ x 6 mm L, which were granulated with the same composition and under the same conditions as 5.
Put it in a rotary kiln of 0mmφ x 2000mmL,
The temperature was raised to a predetermined temperature at a heating rate of 90° C./H under a nitrogen stream, maintained at this temperature for 1 hour, and then cooled in a furnace to obtain a carbide. Table 10 shows the measurement results of the nitrogen and oxygen adsorption properties of the carbide.

In sample 20, which was obtained at a heat treatment temperature during carbonization lower than that of the present invention, the amount of oxygen adsorption and the difference in adsorption amount Δ
Both Q and selectivity coefficient α are small, making it undesirable as a molecular sieve carbon. Sample No. 21, 22, 23 are oxygen adsorption amounts,
It can be seen that both the adsorption amount difference ΔQ and the selection coefficient α are large, making it practical as a molecular sieve carbon, and the characteristics of sample 22 are particularly excellent. Further, in sample 24 obtained at a temperature higher than that of the present invention, the amount of oxygen adsorption and the difference in adsorption amount ΔQ are small, which is not preferable.

[0064]

[Table 10]

Example 6 Using each of the samples produced in Example 5, an experiment was conducted to separate nitrogen and oxygen in the air by the PSA method under the same conditions as in Example 2. The results are shown in Table 11. As shown in Table 5, Sample 20, which was obtained at a heat treatment temperature during carbonization lower than that of the present invention, had poor separation performance. Sample No. 21,2
It can be seen that Nos. 2 and 23 have excellent separation performance. Moreover, sample 24 obtained at a higher temperature than the present invention had poor separation performance.

[0066]

[Table 11]

[0067]

[Brief explanation of the drawing]

FIG. 1 shows an adsorption property measuring device used in Examples 1 to 5.

[Figure 2] Pressure swing adsorption (PSA) used in Example 6
) is an explanatory diagram of the device.

[Explanation of symbols]

1 Vacuum pump 2, 3, 8, 11, 12, 13 Valve 4 Sample chamber 5 Adjustment chamber 6, 7 Pressure sensor 9 Recorder 10 Pressure gauge 14, 15 Gas regulator 16 Nitrogen cylinder 17 Oxygen cylinder 21 Air compressor 22 Air dryer 23, 23a Adsorption tower 24, 24a, 27, 27a, 30, 30a, 35, 3
7 On-off valve 28 Exhaust pipes 29, 29a Outlet pipe 31 Main pipe 34 Reservoir tank 36 Product gas outlet pipe

Claims (1)

[Claims] Claim 1: At least one resin powder selected from the group consisting of phenol resin powder, melamine resin powder, or modified resin powder thereof; and at least one binder component selected from coal tar, pitch, and creosote oil. A method for producing molecular sieve carbon, which is characterized by mixing, forming into granules, and then carbonizing.