JPS634846A - Adsorbent for carbon monoxide - Google Patents

Abstract

PURPOSE:To obtain the titled adsorbent free from the deterioration of performance even if repeating adsorption and desorption by using polystyrene resin having amino group and cuprous chiocyanate as constitutional components. CONSTITUTION:Cuprous chiocyanate and a solvent (i.e. acetonitrile or the like) are mixed and stirred. Then dried polystyrene resin having amino group is added thereto in 0.1-30 preferably 0.5-3 molar ratio for cuprous thiocyanate and stirred. The mixture is heated under reduced pressure to sufficiently distill the solvent and an adsorbent being a solid for carbon monoxide is obtained. The obtained adsorbent quickly adsorbs carbon monoxide under ordinary temp. and ordinary pressure and adsorbed carbon monoxide can be desorbed by heating this adsorbent or decompressing it or reducing the partial pressure of carbon monoxide. Therefore carbon monoxide can be easily separated from a gaseous mixture. Furthermore the performance of this adsorbent is not deteriorated even if repeating adsorption and desorption.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of industrial application] The present invention relates to a carbon oxide adsorbent used for separating carbon monoxide from a mixed gas containing carbon oxide.

[Conventional technology]

Carbon monoxide is a basic raw material in synthetic chemistry, and is produced from coke and coal using generator furnaces, water gas furnaces, Winkler furnaces, Lurgi furnaces, and Kotsu-kusu furnaces. Also,
Produced from natural gas and petroleum hydrocarbons by steam reforming and partial oxidation. In these methods, the product is obtained as a mixture of gases such as -v carbon, hydrogen, carbon dioxide, methane and nitrogen.

For example, in the case of water gas - carbon oxide 35-40%,
Hydrogen 45-51%, carbon dioxide 4-5%, nitrogen 4-9%
It usually contains 1000 to 2000 ppm of water. Carbon monoxide, which is produced as a by-product in steel mills, oil refineries, and petrochemical plants, can also be obtained as a mixed gas.

In order to use these carbon oxides as raw materials for synthetic chemicals, it is necessary to separate carbon monoxide from the mixed gas.

On the other hand, hydrogen is also an important raw material in the chemical industry, and is separated from the various gas mixtures mentioned above or from the waste gas of petrochemical plants, such as the waste gas of hydrocarbon dehydrogenation processes. It often contains Since this carbon oxide becomes a catalyst poison for the catalyst for reactions using hydrogen, it is necessary to separate and remove it. Additionally, these waste gases usually contain a small amount of water.

A liquid absorbent is usually used to separate and remove carbon monoxide from a mixed gas.

The solution cleaning method involves adding a mixed gas to an ammoniacal aqueous solution of GiM@(1) or a hydrochloric acid suspension of chlorinated steel (1) at room temperature for 15 minutes.
Carbon monoxide is separated and removed by pressurizing it to 0 to 200 atm and absorbing it, and then the carbon monoxide is released and separated by heating this solution under reduced pressure, and the solution is regenerated. However, it has disadvantages such as difficulty in operating the liquid absorbent dam, difficulty in controlling the operation to prevent equipment corrosion, solution loss, and sediment formation, and high construction costs due to high pressure. .

According to British Patent No. 1.31 A790, a toluene solution of copper aluminum tetrachloride (Cu(AtC14)), when contacted with a gas mixture containing 50 mn and 6% of carbon monoxide at 25°C, produces -carbon oxide. By absorbing carbon monoxide and heating it to 80°C, 95% of carbon monoxide can be recovered. This absorption liquid absorbs the hydrogen and carbon dioxide contained in the mixed gas.
Although it has advantages such as being unaffected by methane, nitrogen, and oxygen and having a low absorption pressure, it irreversibly reacts with water, resulting in deterioration of absorption capacity and formation of precipitates, and generates hydrochloric acid. For industrial implementation, K is 1 for water in the mixed gas.
It must be strictly controlled to below ppm. Therefore, a strong dehydration process of the mixed gas is required before the absorption process, and strict control is essential. In addition, steel aluminum tetrachloride reacts strongly with water and irreversibly loses its ability to absorb carbon monoxide, so even if it is brought into contact with a mixed gas containing 1 ppm of water, the throughput of the mixed gas will be reduced. Not only does the number of deactivation plates gradually increase as the amount of water increases, but it also has the disadvantage that equipment corrosion progresses due to the hydrochloric acid produced by the reaction with water. In addition, when this absorption liquid is used, it is inevitable that toluene vapor will be mixed into the recovered carbon monoxide, and a device to remove this toluene is required. It has disadvantages such as being subject to process constraints.

Cryogenic separation is a method for obtaining high-purity carbon monoxide. This cools and liquefies the mixed gas, -165 to -
This method involves fractional distillation at a low temperature of 210℃, but it requires complicated freezing and
It requires a heat recovery system, generates dust, uses high-grade materials, is expensive, and consumes a lot of power. Furthermore, if the mixed gas contains water, carbon dioxide, etc., a clogging accident will occur in the cryogenic tube system, so it is necessary to reduce the water to 1r'Ipm or less in pretreatment equipment.

[Problem that the invention attempts to solve]

The present invention provides a novel adsorbent for selectively separating carbon monoxide from a mixed gas, which can overcome the disadvantages and difficulties of carbon monoxide separation techniques using liquid absorbents or cryogenic separation methods. This is a book that says.

Means for Solving the Problem c] The present inventors 1 have developed a material yI that selectively adsorbs carbon oxide.
As a result of intensive search for K, it was discovered that a solid composed of polystyrene resin having an amino group and copper thiocyanate (J) is extremely effective in adsorbing and separating impersonated carbon in a mixed gas, and the present invention has been completed.

That is, the present invention provides a novel adsorbent which is effective in separating carbon monoxide in a mixed gas and is characterized by comprising a polystyrene resin having an Abano group and copper thiocyanate (1) as constituent components. Regarding.

[Effect]

The adsorbent of the present invention can be obtained by mixing and stirring a polystyrene resin having an amino group and thiocyanic acid@(1) in a solvent, and then removing the solvent by a method such as reduced pressure or distillation.

The carbon monoxide adsorption ability of this adsorbent is due to the combination of polystyrene resin having an ABANO group and copper thiocyanate (). Thiocyanic acid? pJ(
With 1) alone, no carbon oxide adsorption ability was observed.

The polystyrene resin having an abano group, which is a constituent component of the adsorbent of the present invention, is, for example, a polymer of styrene or a styrene derivative, or a copolymer of styrene or a styrene derivative and ethylene or an engineered styrene derivative, in which the amino group is directly Or it is a resin bonded via other atomic groups such as methylene groups or ethylene groups.

On the other hand, the solvent used in the preparation of the adsorbent of the present invention includes, for example, acetonitrile, tetrahydrofuran, diethyl ether, and the like.

Regarding the composition of the adsorbent of the present invention, thiocyanic acid M l) of the amino group of the resin which is a constituent component of the adsorbent.
The molar ratio to ttc is 11-30, preferably 15-3
It is.

The adsorbent of the present invention rapidly adsorbs carbon monoxide under normal pressure, and by heating the adsorbent, reducing the pressure, or lowering the partial pressure of carbon oxide, Since the adsorbed carbon monoxide can be desorbed, it is possible to easily separate carbon monoxide from the mixed gas.

Next! Now, the present invention will be further explained by examples.

〔Example〕

Example 1 An adsorbent of the present invention was prepared as follows. No trench, internal volume 1
Thiocyanic acid @(1) in a 00 Wlt eggplant flask
s t (a 1.1 rn mat ) and 20 - of acetonitrile were added and mixed at room temperature using a magnetic stirrer. Then the mixture K, 5? in this flask? lll
Drying was carried out at 80° C. for 10 hours under a reduced pressure of 1Hf. To polystyrene resin W having amino groups manufactured by Mitsubishi Chemical Industries, Ltd. 20 (contains 51 primary and secondary amino acids) &
After adding 5 f of S m mOA/f-dry resin), sealing the flask and stirring the flask contents at room temperature for 6 hours, acetonitrile was thoroughly distilled off while stirring at 80 °C under a reduced pressure of 5 mHf. A gray-green granular solid was obtained. This is - carbon oxide adsorbent.

Adsorbent 5 above? The flask was placed in an oval-shaped flask with an internal volume of 100-100 mm, and the mixture was kept at 80° C. for 1 hour while being evacuated under a vacuum of 5 m1n9, and then allowed to cool to room temperature under reduced pressure.

Next, this □ eggplant-shaped flask was heated to 1 atm of carbon monoxide 3
-carbon oxide was brought into contact with the adsorbent at room temperature, and the adsorbed amount of -carbon oxide was measured by the gas buret method.

Carbon monoxide adsorption begins quickly, after 10 minutes! I
i”b 37 m mot of carbon monoxide is adsorbed, 6
The amount of carbon monoxide adsorbed after 0 minutes reached 4.51 m moj.

Next, using a vacuum pump, the inside of the eggplant-shaped flask containing the carbon oxide adsorbent was evacuated at room temperature under a reduced pressure of 5 mHf for 20 minutes to desorb the adsorbed carbon oxide. This eggplant flask was then connected to a container containing 5 tons of carbon monoxide at 1 atm, and the -carbon oxide was brought into contact with the adsorbent at room temperature.

Carbon monoxide adsorption begins quickly, and after 10 minutes, 2
．． 72 m mot of carbon monoxide was adsorbed, and the amount of carbon monoxide adsorbed after 60 minutes reached l 46 m rnaL.

Thereafter, even if the above operation was repeated, no change was observed in the adsorption rate and amount of -+1e carbon.

The eggplant-shaped flask containing the -carbon oxide adsorbent was then combined with a container containing 1 atm of nitrogen gas (concentration of 1 l 1000 pp of water) 2 OL containing 160 q (a9 mmot) of water, and the water was evaporated at room temperature. was contacted with the adsorbent for 6 hours. The eggplant flask was then coupled to a container containing 5 tons of carbon monoxide at 1 atm, and -1 atomized carbon was contacted with the adsorbent at room temperature.

- Adsorption of carbon oxide started quickly (C, 2.72 mmOL of carbon monoxide was adsorbed after 10 minutes, and the adsorption amount of carbon monoxide reached 547 mmNL after 60 minutes.

That is, the adsorption rate and amount of -carbon oxide hardly changed even when the adsorbent was brought into contact with a gas containing 11,000 ppm of water.

Example 2 Carbon monoxide adsorption amount 52 prepared in the same manner as in Example 1 was placed in a 100-mm internal volume glass-shaped flask, kept at 80°C for 1 hour while being evacuated under a reduced pressure of 5 naHt, and then heated under reduced pressure. It was left to stand until it reached room temperature. Next, this eggplant-shaped flask was connected to a container containing 5 tons of carbon monoxide at 1 atm, and -carbon oxide was brought into contact with the adsorbent at room temperature, and the -carbon oxide adsorption meter was used to measure the amount by gas buret method.

- The adsorption of carbon oxide started quickly, and after 10 minutes, 537 m mot of carbon monoxide was adsorbed, and after 60 minutes, the adsorption amount of carbon monoxide reached 4.51 m mot.

Next, this adsorbent was heated to 80° C. under 1 atm, and the desorption rate of -carbon oxide was measured by the gas buret method. −
The carbon oxide was quickly desorbed and reached desorption 1i (minute diameter 9 mm·)t after 10 minutes of desorption. As a result of analyzing the desorbed gas with a gas chromatograph, the desorbed gas was only carbon monoxide, and no other components were detected. There wasn't.

After that, the eggplant-shaped flask containing the adsorbent that had desorbed the -carbon oxide was allowed to cool while passing nitrogen through it, and then combined with a container containing 3 tons of carbon monoxide at 1 atm, and the flask was placed at room temperature to adsorb the -carbon oxide. was brought into contact with the agent.

Adsorption of carbon monoxide begins quickly, and after 10 minutes, A
O3m mat of carbon monoxide was adsorbed, and the amount of carbon monoxide adsorbed after 60 minutes reached l 89 m motK.

Comparative Example Resin WA205F, which had been dried in the same manner as in Example 1, was placed in an oval-shaped flask with an internal volume of 100-100 mm, and the flask was kept at 80°C for 1 hour while being evacuated under a reduced pressure of 5 mHt, and then brought to room temperature under reduced pressure. I left it until it was done. This eggplant-shaped flask was then combined with a container containing 1 atm of carbon monoxide 5, and -
Although carbon oxide was brought into contact with the resin, no adsorption of carbon oxide was observed.

On the other hand, in the same way as above, -carbon oxide was replaced with copper thiocyanate (1
), but no adsorption of -carbon oxide was observed.

〔Effect of the invention〕

As is clear from the results of the examples, the adsorbent of the present invention has the following properties:
It can quickly adsorb carbon monoxide at room temperature and pressure, and desorb the adsorbed carbon monoxide with simple operations.
Carbon monoxide can be easily separated from mixed gas, adsorbed,
It is an excellent adsorbent that does not deteriorate in performance even after repeated desorption.

Furthermore, since the carbon monoxide adsorbent of the present invention is solid, devices such as packed column type, packed column type, and fluidized bed type can be used as devices for adsorption and desorption of carbon monoxide. (Clean with an adsorbent that does not deteriorate even in the presence of moisture.)

Sub-agent: 1) Akira Sub-agent Ryo Hagi Hara - Sub-agent Atsuo Yasunishi

Claims (1)

[Claims] Polystyrene resin with amino groups and copper thiocyanate (
A carbon monoxide adsorbent characterized by comprising I) as a constituent component.