JPS6118420A - Gas permselective membrane - Google Patents

Abstract

PURPOSE:To separate carbon monoxide in high yield by retaining the reaction product between copper compd. and pyrazoles, triazoles or tetrazoles on the membrane of a supporting body. CONSTITUTION:The reaction product between copper compds. and pyrazoles, triazoles and/or tetrazoles is retained on a membrane which has property permeating gasess. The mixing ratio is a proportion of 0.1-100mol ratio per copper compds. and regulated to >=0.1% concn. in case of using solvent. The operation is performed at 0-200 deg.C under inert gas stream. As the method for retaining the reaction product on the membrane of a supporting body, the method for burying the reaction product to the meshes of crosslinkable high polymer which are formed on the supporting body and the method for retaining the reaction product as a liquid membrane having specified thickness on the supporting body film, etc., are used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a selectively permeable membrane for gas. Specifically, a specific reaction product was retained alone or as a solution on a membrane serving as a support. The present invention relates to a gas selective permeation membrane suitable for permeation of gases, particularly carbon oxide.

[Conventional technology]

Conventionally, various polymer membranes have been known as separation membranes for gas mixtures, but these membranes have relatively low gas permeation coefficients, and materials with high permeation coefficients are desired. When the membrane is liquid, the gas diffusion coefficient is generally large, and therefore the permeation coefficient can be increased. Furthermore, when such a liquid membrane contains a substance that selectively and reversibly interacts only with a certain gas, it is possible to further increase the permeability of that gas. On the other hand, the selective performance of a membrane is determined by the difference in solubility of gases in the membrane.

Many examples of such membranes containing substances that selectively and reversibly interact only with certain gases are known.1 For example, separation of carbon dioxide gas using an aqueous solution of bicarbonate of an alkali metal. (Special Publication No. 4tj-//74), Separation of olefins using an aqueous solution of silver nitrate (No. 63-3/♂tar), Separation of nitrogen monoxide using a formamide solution of ferrous chloride (A, Engineering Oh HJournal vol #A
34tθj Page 7970), etc., and these liquid films are used by being held on a film that serves as a support. Furthermore, for the separation of carbon oxide, an aqueous hydrochloric acid solution of copper oxide is known, but in this case there is a drawback that a concentrated aqueous hydrochloric acid solution must be used. Also, secondary example of permeation (outflow side)
When reducing the pressure to 0. As a result of examining substances that allow permeation of water vapor and hydrogen chloride gas and have selectively reversible interactions with contamination with other gases, we found that reaction products between copper compounds and pyrazoles, triazoles, and/or tetrazoles The present invention was achieved based on the fact that the membrane retaining the above significantly promotes the permeation of carbon monoxide and exhibits very high selective separation performance of carbon monoxide and high permeation rate of carbon monoxide.

[Means for solving problems]

That is, the gist of the present invention resides in a gas selective permeation 3a membrane in which a reaction product of a copper compound and pyrazoles, triazoles, and/or tetrazoles is held in a membrane serving as a support.

The present invention will be explained in detail below.

The copper compounds used in the present invention are not particularly limited, but include:
Cuprous chloride, λ cupric chloride, cuprous oxide, λ cuprous oxide, cuprous bromide, cupric bromide, cuprous cyanide, cupric cyanide
Copper, copper thiocyanate, fluorinated steel, iodized steel, copper sulfide, copper sulfate, etc. are exemplified, and these can be used alone or as a mixture. Among these, cuprous sulfide, cuprous thiocyanate, cuprous chloride, and the like are particularly suitable copper compounds.

On the other hand, bigols include pyrazoles and derivatives thereof. These compounds are described in Dai Organic Chemistry (Breakfast Shoten, supervised by Munio Kotake/volume J′, 1996 edition of Showa Guko),
2! ? Negative~33! A book that lists the compounds listed on the page.

In other words, pyrazole is a pyrazole.

Contains pyrazoline, pyrazolone, biglysine, pyrazolidone, indazole.

Specific compounds include pyrazole, /-lupyrazole, dark tetrarubi2zole, oxypyrazole, daasanopyrazole, /pyrazolecarboxylic acid, 2-pyrazoline s 3-methyl-pyrazoline, tamethyl-/-phenylrubi2purine, copy2 Zoline-3 carboxylic acid.

! -Pyrazolone, 3-methyl-! Pyrazomen.

3-amino-! -Pyrazolone, /-7enylvirasoricin, 3-methyl-7-7enyl! -pyrazolidone, inidazole, /-methylindazole, 3-bromoindazole and the like.

Moreover, triazoles include triazoles and derivatives thereof. These compounds include the aforementioned large organic chemistry, 34? Examples include the compounds described on pages 4107 to 4107.

That is, the triazoles include /, λ, J) lyazole, be/citrizole, /, 4t triazole, /-methyl-/, co, 3-triazole.

4t-7air/, 2. j-) Riazole! −Aλ
, 4 is monotriazole, 3-rirumi 7, 2. Examples include datriazole, /-amino-/, 2.4t-triazole, and the like.

Furthermore, tetrazoles include tetrazole and its derivatives. These compounds are described in the above-mentioned Dai Organic Chemistry, pages 4to♂ to 4tJ, page 2. Examples include compounds. In other words, as a specific compound,
Tetrazole, /-Methyltetrazole, 2-methyltetrazole%t,z diphenyltetrazole,! oxynato 2 zole, /-amino-! -phenylteto dizole and the like.

These compounds (pyrazoles, triazoles, tetrazoles) may be used alone or in combination of one or more. Also, two or more of different types may be used in combination.

Copper compounds, pyrazoles, triazoles.

If the tetrazoles are commercially available products, they may be used as they are or may be further purified.

When the pyrazoles, triazoles, and tetrazoles are liquid, they can be used as solvents themselves, or other solvents can also be used.

If it can be used as a solvent as it is, it is convenient for facilitated transport of substances that have a high concentration of substances that reversibly interact with specific gases, such as carbon monoxide.

When the bisizoles, triazoles, and tetrazoles are solid, it is preferable to use a solvent to dissolve or dissolve the biraboles, triazoles, and tetrazoles.

In this case as well, the higher the solubility in the solvent, the more advantageous it is for facilitated transport.

Solvents include pyrazoles and triazoles.

Anything that dissolves tetrazoles may be used,
For example, ketones, esters, and ethers.

Alcohols, amines, amides, other metal-containing elemental compounds, sulfur-containing compounds, phosphorus-containing compounds, and halogen-containing compounds can be used. Acetone, ethyl acetate, acetonitrile,
Methanol, ethanol, etc. are suitable in that they dissolve well the lyazoles and disoles. On the other hand, 1, for example, acetophenone, N-methyl-
Pyrrolidone, r-butyro 2 ctone, ethylene glycol, nato 2 ethylene glycol dimethyl ester, polyethylene glycol.

When using a solvent with relatively low vapor pressure, such as glycerin, dimethyl sulfoxide, benzonitrile, etc., room temperature is sufficient.

When conducting at higher temperatures, copper compounds, pyrazoles, and triazoles are solid at room temperature.

□□1□Beak "□+1 θ, /< Virazoles, triazoles, tetrazoles/copper compounds 10θ (molar ratio) is desirable, θ,!<
Pyrazoles, triazoles.

Tetrazoles/copper compounds! θ (molar ratio) is particularly desirable.

On the other hand, when a solvent is used, the ratio of pyrazoles, triazoles, or tetrazoles to the solvent is usually selected such that pyrazoles, triazoles, or tetrazoles/solvent>0,007 or more.

In this case, the ratio of copper compound to virazoles, triazoles, tetodizoles is chosen in the same way as above.

The reaction temperature is generally 0-200° C., and preferably carried out under an inert gas stream.

In the next step, the support used to hold the reaction product of the copper compound thus obtained and the pyrazoles, triazoles, and tetrazoles may be a membrane having a gas permeable property and is not particularly limited.

do not. Furthermore, the holding method is not particularly limited as long as the holding allows selective permeation of gases, especially -carbon oxide. A method of filling the pores of a porous support with a solution of a substance, and a method of embedding it in a crosslinkable polymer network formed on a support membrane.

Examples include a method of retaining it as a liquid film having a constant thickness on a support membrane, and a method of retaining it in arranged molecules formed on a support.

The type of membrane material used as the support is not particularly limited, but includes regenerated cellulose, cellulose ester, polycarbonate, and polyester.

Tefine, nylon, acetyl cellulose, polyacrylonitrile, polyvinyl alcohol.

Polymethyl methacrylate, polysulfone.

polyethylene, polypropylene, polyvinylpyridine,
Organic polymers such as polyenylene oxide, poly7-enylene oxide sulfonic acid, polybenzimidazole, polyimidazopyrrolone, polypibenzine amide, polystyrene, polyamino acid, polyurethane, polyamino acid polyurethane copolymer, polysiloxane, and polysiloxane polycarp. , glass, aluminum, silica, silica alumina,
Inorganic substances such as carbon and metals can be used.

You can. These supports may be porous as a whole, an anisotropic film with a dense layer only on the surface, or a homogeneous film. It may also be coated with a thin film of another material by a method. Although the overall thickness is not particularly limited, it is preferably in the range W of 10 to 10θθμ. Such a support can also be used by superimposing and supporting a support made of another material.

The layer thickness of the reaction product between the copper compound and the pyrazole, triazole, or tetrazole supported on these supports can be several angstroms or more, and the limiting constant, equilibrium constant, etc. It varies depending on the conditions, but it is approximately 0.07~! It is used at a film thickness of θ00θμ, more preferably θ/~10000μ. In addition, when a liquid film is used under stirring, there is no problem even if the film thickness is thick, but the actual film thickness that exists as a diffusion layer on the surface of the support film is the same as the film thickness in the case without stirring. It is preferable that there be.

Copper compounds, pyrazoles, and triazoles There are various methods that can be used to separate gases using membranes that hold copper compounds. It is used with a partial pressure difference between the gases to be separated on both sides. In addition, a container containing a reaction product or a solution thereof of a copper compound and pyrazoles, triazoles, and/or tetrazoles is placed separately from the membrane cell, and a pump is used to pump this liquid onto the surface of the support membrane of the membrane cell. It is also possible to use a method in which the material is introduced to the primary side of the membrane and circulated. In this case, for example, carbon oxide is sufficiently absorbed into a liquid in a reservoir container, and then the carbon monoxide is transferred to a membrane cell in a highly selective and continuous manner at the temperature of the n part. is not particularly limited, but for example, θ~, 20θ
It can be used in the range of ℃.

A reaction product of a copper compound and a pyrazole, a triazole, and/or a tetrazole or a solution thereof is supported on a membrane serving as a support. Another method is to fill the pores of a porous support with the reaction product or its solution, and to maintain the reaction product or its solution by dissolving or dispersing it in a thin film of the support. There are many possible methods.

The method of retaining the reaction product includes a method of dissolving or dispersing it in a component having regularly arranged molecules such as liquid crystal.

〔Effect of the invention〕

The gas separation membrane thus obtained can be advantageously used mainly for separating carbon monoxide. For example, carbon monoxide can be mainly separated in high yield from a mixed gas containing natural carbon oxide, and can be used as a raw material in various chemical reactions.

〔Example〕

Next, the present invention will be explained using examples.

Example / Under a stream of dry nitrogen, cost 9 azole (commercial product used as is) was collected in a flask, and N-methylvirolidone (commercial product was dehydrated and deoxygenated) was added to it. Things/! - Added and stirred. After a while, the solution became homogeneous.

Cuprous thiocyanate (a commercially available product was used as it was) was added to this and stirred. For a while Sui and K became a homogeneous solution.

On the other hand, an asymmetric membrane of polytrimethylvinylsilane was attached to a cell for gas permeation measurement, and the skin layer side was subjected to primary treatment. The nitrogen permeation rate of this membrane is: OX/0-'C11
l/6d・me -3111g.

The above homogeneous solution is poured onto this membrane under a stream of inert gas.
- Added and stirred. After reducing the pressure on both the downstream side and the secondary side, a gas of 1 kg/cd was flowed into the downstream side, and the secondary side was evacuated to measure the permeability of various gases using gas chromatography. Pure gas was used as the measurement gas.

The results are shown in Table 1. As can be seen from the table, the permeability of carbon monoxide was much higher than that of other gases, and it can be seen that the permeation of only carbon oxide gas was selectively promoted.

Furthermore, this method has the advantage that even 7 droplets of N-methylimidazole do not pass through to the secondary side during the experimental operation, and because the vapor pressure of N-methylimidazole is low, the vapor does not pass through either. (I experimented with a trap tube attached, but not even 7 drops had accumulated.) Comparative Example / /-, 4t-) Glue of solution of reaction product of lyazole and cuprous thiocyanate, bK, N-methylpyrrolidone / , 2. The permeation rate of various gases was measured in the same manner as in Example/using only J m. The results are shown in Table-/.

Example 1: 2,41-triazole, 3. Example/ except that j-dimethylpyrazole &, jJ f were used.
The permeation rates of various gases were measured using exactly the same method as described above.

The nitrogen permeation rate of the polytrimethyl and nylsilane group used was 3.7 x/θ-'m/d·formula·Hg.

Example 3 and copper(I) chloride or copper(I) chloride and 3. ! The permeation rate of various gases was measured in the same manner as in Example 1 using the reaction product of -dimethyl-/-ruvirazole. The results are shown in Table-/.

Claims (1)

[Claims] (1) A gas selective permeation membrane in which a reaction product of a copper compound and pyrazoles, triazoles, and/or tetrazoles is held in a membrane serving as a support.