JPS6240333B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adsorption separation agent and an adsorption separation method for separating unsaturated hydrocarbons from a mixed gas containing unsaturated hydrocarbons along with nitrogen, oxygen, methane, ethane, carbon dioxide, hydrogen, etc. .

Unsaturated hydrocarbons such as olefins and dienes are important basic substances in the chemical industry;
Produced by pyrolysis of saturated hydrocarbons such as natural gas, refinery gas, and petroleum fractions. Furthermore, off-gas produced as a by-product from fluid catalytic cracking equipment and purge gas from various processes may also contain a considerable amount of unsaturated hydrocarbons. However, in these cases, unsaturated hydrocarbons are obtained as a gas mixture with nitrogen, oxygen, methane, ethane, carbon dioxide, hydrogen, etc. Additionally, this gas mixture usually includes
Contains 1000-20000ppm of water. Therefore, in order to use unsaturated hydrocarbons as raw materials for chemical industries, it is necessary to separate them from a mixed gas.

Cryogenic separation is a method for separating unsaturated hydrocarbons from a mixed gas. This is a method of cooling and liquefying a mixed gas and fractionating it at a low temperature, but it requires a complicated refrigeration and heat recovery system, the equipment is expensive because it uses high-grade materials, and it consumes a lot of power. There are other difficulties. Furthermore, if water and carbon dioxide are included in the mixed gas, a blockage accident will occur in the cryogenic tube system, so it is necessary to remove water and carbon dioxide to 1 ppm or less using pretreatment equipment.

US Pat. No. 3,651,159 describes that a toluene solution containing copper()aluminum chloride has the ability to separate unsaturated hydrocarbons by complexing them. However, copper()aluminum chloride reacts strongly with water and irreversibly loses its ability to form complexes, so even if it is
Even with water, the separation ability gradually decreases as the throughput of mixed gas increases, and the hydrogen chloride generated by the reaction also causes corrosion of the equipment. In addition, since toluene vapor used as a solvent is contained in the recovered unsaturated hydrocarbons, a device to remove this toluene is required, and there are disadvantages such as process constraints due to the use of liquid absorbent. have Furthermore, since the absorption liquid contains aluminum chloride, the Friedel reaction between toluene and unsaturated hydrocarbons using aluminum chloride as a catalyst
-Crafts reaction occurs as a side reaction, resulting in loss of unsaturated hydrocarbons and alteration of the liquid absorbent.

Although various other methods have been proposed, no method for separating unsaturated hydrocarbons from a mixed gas is yet completely satisfactory.

The present inventors have been conducting research on gaseous solid adsorbents for many years, and now we have developed a solid adsorbent consisting of a halide salt of copper () or copper oxide () and activated carbon. halide salt,
It was discovered that solid adsorbents composed of carboxylates, sulfates, basic salts, ammine complex salts, or copper oxide and activated carbon adsorb and release unsaturated hydrocarbons under mild conditions. . Based on this discovery, as a result of intensive research, we succeeded in separating and refining or separating and removing unsaturated hydrocarbons from a mixed gas in a technically and economically easy and advantageous manner, and completed the present invention. did.

The solid adhesive in the present invention is a halide salt of copper (2) or copper (I) oxide, or a halide salt, carboxylate, sulfate, basic salt, or amine complex salt of copper (2), or copper (1) oxide as a solvent. This is a solid adsorbent obtained by dissolving or suspending the adsorbent, adding activated carbon thereto, stirring thoroughly, and then removing the liquid phase by distillation under reduced pressure.

Solvents used in the preparation of the solid adsorbent in the present invention include, for example, water, aqueous hydrochloric acid, formic acid, acetic acid, benzene, toluene, propionitrile, acetonitrile, ammonia water, ammoniacal formic acid aqueous solution, and carbon atoms of 1 to 7. primary or secondary alcohols, etc.

In the present invention, the mixed state of the copper salt and copper oxide with the solvent may be partially suspended.

The activated carbon used in the present invention is shaped like compacted coal, granular coal made of crushed coal, and powdered coal. Raw materials for activated carbon include wood, coconut grain,
Coal, oil-based pitch, etc. are used, and a chemical activation method, a gas activation method, etc. can be applied to this activation method.

Examples of the halide salt of copper ( ) used in the present invention include copper chloride ( ), copper bromide ( ), and copper iodide ( ). Also, these copper()
Copper oxide () can also be used instead of halide salts.

Examples of the halide salts of copper (2) used in the present invention include copper chloride (2), copper fluoride (1), copper bromide (2), and copper iodide (2).
Examples of carboxylic acid salts of copper () include copper acetate () and copper formate (). Examples of basic salts of copper () include basic copper carbonate (), basic copper acetate (), and basic copper phosphate (). Examples of ammine salts of copper() include copper() hexaammine chloride. Moreover, copper() oxide can also be used instead of these copper() salts.

Activated carbon and copper() salt, copper() oxide, copper() in the production of unsaturated hydrocarbon adsorbent according to the present invention
The weight ratio with salt or copper oxide () is 0.5~
60.0, preferably 2.0 to 10.0. Further, the weight ratio of the solvent to the copper () salt, copper () oxide, copper () salt, or copper () oxide () is 1 to 200, preferably 3 to 30.

Unsaturated hydrocarbons that can be separated by the present invention include, for example, monoolefins, polyolefins, and dienes having 2 to 15 carbon atoms.

The adsorption of unsaturated hydrocarbons in the present invention can be carried out at -40 to 90°C, preferably 0 to 40°C, under normal pressure, and the adsorption can be carried out at 40 to 250°C, preferably 60 to 40°C.
The adsorbed unsaturated hydrocarbons can be released by increasing the temperature to 180°C or by lowering the partial pressure of the unsaturated hydrocarbons. Adsorption of unsaturated hydrocarbons can be carried out at temperatures of 90° C. or higher by increasing the pressure of the mixed gas to 1 atm or higher.

The adsorbent according to the present invention is inert to water in a gas mixture, and by using this adsorbent, unsaturated hydrocarbons can be directly separated from a water-containing gas mixture, as shown in the examples. It is possible,
Even after repeated use, there is hardly any decrease in the adsorbent's ability. Furthermore, this adsorbent does not catalyze the Friedel-Crafts reaction for unsaturated hydrocarbons.

Since the adsorbent according to the invention is a solid, devices such as packed column type and fluidized bed type can be used as devices for adsorption and desorption of unsaturated hydrocarbons.

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

Example 1 As copper chloride (), a special grade reagent manufactured by Koso Chemical Co., Ltd. was used. Hydrochloric acid is a first-class reagent manufactured by Takahashi Fujiyoshi Shoten, and purified water (manufactured by Tokyo Yakuhin Kogyo Co., Ltd.)
It was diluted to 3N using . Activated carbon is
BAC manufactured by Kureha Chemical Industry Co., Ltd., G-70R,
LOT, No. 810117, (petroleum-based pitch coal raw material, steam activated) was heated and kept at 180°C for 24 hours under reduced pressure (6 mmHg), and then stored under dry nitrogen. For ethylene gas, cylinder gas manufactured by Takachiho Chemical Co., Ltd. was used, and the water content was 0.6 mol%.
(6000ppm). In addition, the nitrogen gas was purified by passing a cylinder gas manufactured by Suzuki Shokan Co., Ltd. through a column packed with molecular sieve 3A immediately before use.

1.5 g in a 100 ml two-necked eggplant flask under nitrogen
(15.2 mmol) of copper chloride () was added, and 3N hydrochloric acid was added.
15 ml was added and left at 20°C for 1 hour while stirring using a magnetic stirrer. 10 g of activated carbon was added to this eggplant flask under dry nitrogen, and after stirring for 1 hour, the inside of the eggplant flask was depressurized (6 mm
Hg) and heated and kept at 100°C to sufficiently remove water and hydrogen chloride to obtain black grains. This is a solid adsorbent.

This solid adsorbent was placed in a 100 ml two-necked eggplant flask, combined with a container containing 1 atm of a mixed gas of ethylene and nitrogen (ethylene partial pressure 0.9 atm, nitrogen partial pressure 0.1 atm), and stirred using a magnetic stirrer. Ethylene was adsorbed at 20°C while stirring. During the initial 10 minutes of adsorption, a BA-106T air pump manufactured by Iwaki Co., Ltd. was used to circulate the mixed gas and pass it over the adsorbent. The amount of ethylene adsorption was measured at 20°C using the gas brew method.

Adsorption of ethylene is rapid, 3.4 mmol after 10 minutes
of ethylene was adsorbed, and the amount of ethylene adsorbed after 60 minutes was 4.5 mmol.

Next, this adsorbent was heated to 100° C. at 1 atm, and the amount of gas released was measured by the gas billet method. Ethylene was rapidly released, reaching 4.5 mmol after 10 minutes. Analysis of the released gas using a gas chromatograph revealed that the released gas was ethylene and no other components were detected.

After that, it was connected to a container containing 1.5 atm of a mixed gas of ethylene and nitrogen (ethylene partial pressure: 0.9 atm, nitrogen partial pressure: 0.1 atm), and the amount of ethylene adsorption was measured.

Ethylene adsorption was rapid, and the amount of ethylene adsorbed after 60 minutes was 3.4 mmol.

Next, this adsorbent was heated to 100° C. at 1 atm, and the amount of gas released was measured by the gas billet method. Ethylene was released rapidly, reaching 3.4 mmol after 10 minutes.

Thereafter, even if the same adsorption/desorption operation was repeated, no change was observed in the adsorption rate and amount of ethylene.

Example 2 The same reagents and adsorbents as described in Example 1 were used.

Put the solid adsorbent into a 100ml two-necked eggplant flask, and add a mixed gas of ethylene and nitrogen (ethylene partial pressure
0.9atm, nitrogen partial pressure 0.1atm) 1.5, and while stirring using a magnetic stirrer,
Ethylene was adsorbed at 20°C. Initial 10 of adsorption
For a minute, the mixed gas was circulated and passed over the adsorbent using a BA-106T air pump manufactured by Iwaki Co., Ltd. The amount of ethylene adsorption was measured at 20°C using the gas brew method.

Adsorption of ethylene is rapid, 3.4 mmol after 10 minutes
of ethylene is adsorbed, and the amount of ethylene adsorbed after 60 minutes is
The amount was 4.5 mmol.

Next, the pressure inside this two-necked eggplant flask was reduced (0.4 mmHg) at 20°C for 10 minutes using a vacuum pump.
Adsorbed ethylene was released.

After that, this two-necked eggplant flask was filled with a mixed gas of ethylene and nitrogen at 1 atm (ethylene partial pressure 0.9 atm,
Combined with a container containing nitrogen partial pressure 0.1 atm) 1.5,
The amount of ethylene adsorption was measured.

Ethylene adsorption is rapid; after 60 minutes, 3.7 m
Adsorbed mol of ethylene.

Thereafter, even if the same adsorption/desorption operation was repeated, no change was observed in the adsorption rate and amount of ethylene.

Example 3 The same reagents and adsorbents as described in Example 1 were used.

As the propylene gas, propylene (50% xylene solution) manufactured by Tokyo Chemical Industry Co., Ltd. was used by passing it through an activated carbon column.

The solid adsorbent was placed in a 100ml two-necked eggplant flask, combined with a container containing 1.5% of a mixed gas of propylene and nitrogen (propylene partial pressure 0.9atm, nitrogen partial pressure 0.1atm), and stirred using a magnetic stirrer. Propylene was adsorbed at 20°C. During the initial 10 minutes of adsorption, a BA-106T air pump manufactured by Iwaki Co., Ltd. was used to circulate the mixed gas and pass it over the adsorbent. The amount of propylene adsorbed was measured at 20°C using the gas brew method.

Adsorption of propylene is rapid; 4.4 m after 10 minutes.
mol of propylene was adsorbed, and the amount of propylene adsorbed after 60 minutes was 5.7 mmol.

Next, the pressure inside this two-necked eggplant flask was reduced (0.4 mmHg) at 20°C for 10 minutes using a vacuum pump.
The adsorbed propylene was released.

After that, this two-necked eggplant flask was filled with a mixed gas of propylene and nitrogen at 1 atm (partial pressure of propylene).
0.9 atm, nitrogen partial pressure 0.1 atm) was connected to a container containing 1.5, and the amount of propylene adsorbed was measured.

Adsorption of propylene is rapid; after 60 minutes, 3.3
Adsorbed mmol of propylene.

Thereafter, even if the same adsorption/desorption operation was repeated, no change was observed in the adsorption rate and amount of propylene.

Example 4 Copper chloride () dihydrate (manufactured by Koso Chemical Co., Ltd.,
The same reagents as those described in Example 1 were used, except that 3-N hydrochloric acid (special grade reagent) was used and purified water (manufactured by Tokyo Yakuhin Kogyo Co., Ltd.) was used instead of 3N hydrochloric acid.

2.6 g in a 100 ml two-neck eggplant flask under nitrogen
(15.0 mmol) of copper chloride () dihydrate was added thereto, and 15 ml of purified water was added thereto. The mixture was stirred using a magnetic stirrer and left at 20°C for 1 hour. 10 g of activated carbon was added to this eggplant flask under nitrogen, and after stirring for 1 hour, the inside of the eggplant flask was depressurized (6 mm
Hg) and heated and kept at 180°C to thoroughly remove water to obtain black grains. This is a solid adsorbent.

Put the solid adsorbent into a 100ml two-necked eggplant flask, and add a mixed gas of ethylene and nitrogen (ethylene partial pressure
0.9atm, nitrogen partial pressure 0.1atm) 1.5, and while stirring using a magnetic stirrer,
Ethylene was adsorbed at 20°C. Initial 10 of adsorption
For a minute, the mixed gas was circulated and passed over the adsorbent using a BA-106T air pump manufactured by Iwaki Co., Ltd. The amount of ethylene adsorption was measured at 20°C using the gas brew method.

Adsorption of ethylene is rapid, 3.3 mmol after 10 minutes
of ethylene is adsorbed, and the amount of ethylene adsorbed after 60 minutes is
The amount was 4.2 mmol.

Next, the pressure inside this two-necked eggplant flask was reduced (0.4 mmHg) at 20°C for 10 minutes using a vacuum pump.
Adsorbed ethylene was released.

After that, this two-necked eggplant flask was filled with a mixed gas of ethylene and nitrogen at 1 atm (ethylene partial pressure 0.9 atm,
Combined with a container containing nitrogen partial pressure 0.1 atm) 1.5,
The amount of ethylene adsorption was measured.

Ethylene adsorption is rapid; after 60 minutes, 4.0 m
Adsorbed mol of ethylene.

Thereafter, even if the same adsorption/desorption operation was repeated, there was no change in the adsorption rate and amount of ethylene.

Example 5 Copper bromide ( ) (manufactured by Yoneyama Pharmaceutical Co., Ltd., special grade reagent) was used instead of copper chloride ( ) described in Example 1, and 28% ammonia water ( Manufactured by Takahashi Fujiyoshi Shoten Co., Ltd.)
The same reagents as described in Example 1 were used, except that:

2.2 g in a 100 ml two-neck eggplant flask under nitrogen
(15.0 mmol) of copper bromide () was added, 15 ml of ammonia water was added, and the mixture was left at 20°C for 1 hour while stirring using a magnetic stirrer. 10 g of activated carbon was added to this eggplant flask under nitrogen, and after stirring for 1 hour, the inside of the eggplant flask was depressurized (6 mm
Hg) and heated and kept at 100°C to sufficiently remove water and ammonia to obtain black grains. This is a solid adsorbent.

This solid adsorbent was placed in a 100 ml two-necked eggplant flask, combined with a container containing 1 atm of a mixed gas of ethylene and nitrogen (ethylene partial pressure 0.9 atm, nitrogen partial pressure 0.1 atm), and stirred using a magnetic stirrer. Ethylene was adsorbed at 20°C while stirring. During the initial 10 minutes of adsorption, a BA-106T air pump manufactured by Iwaki Co., Ltd. was used to circulate the mixed gas and pass it over the adsorbent. The amount of ethylene adsorption was measured at 20°C using the gas brew method.

Adsorption of ethylene is rapid, 2.3 mmol after 10 minutes
of ethylene is adsorbed, and the amount of ethylene adsorbed after 60 minutes is
The amount was 3.3 mmol.

Example 6 Anhydrous copper sulfate () (manufactured by Yoneyama Pharmaceutical Co., Ltd.) was used instead of copper chloride ( ) described in Example 1, and 35% hydrochloric acid (manufactured by Takahashi Fujiyoshi Co., Ltd.) was used instead of 3N hydrochloric acid. (manufactured by a store) was used.
The same reagents as described in Example 1 were used.

2.4 g in a 100 ml two-necked eggplant flask under nitrogen
(15 mmol) of anhydrous copper sulfate () was added, 15 ml of 35% hydrochloric acid was added, and the mixture was left at 20°C for 1 hour while stirring using a magnetic stirrer. 10 g of activated carbon was added to this eggplant flask under nitrogen, and after stirring for 1 hour, the inside of the eggplant flask was depressurized (6 mm
Hg) and heated and kept at 100°C to sufficiently remove water and hydrogen chloride to obtain black grains. This is a solid adsorbent.

This solid adsorbent was placed in a 100 ml two-neck eggplant flask, combined with a container containing 1 atm of a mixed gas of ethylene and nitrogen (ethylene partial pressure 0.9 atm, nitrogen partial pressure 0.1 atm), and stirred using a magnetic stirrer. Ethylene was adsorbed at 20°C while stirring. During the initial 10 minutes of adsorption, a BA-106T model manufactured by Iwaki Co., Ltd. was used to circulate the mixed gas and pass it over the adsorbent using an air pump. The amount of ethylene adsorption was measured at 20°C by the gas brew method.

Adsorption of ethylene is rapid, 2.0 mmol after 10 minutes
of ethylene is adsorbed, and the amount of ethylene adsorbed after 60 minutes is
The amount was 3.2 mmol.

Comparative Example The activated carbon, ethylene and nitrogen used were the same as those described in Example 1.

Put 10g of activated carbon in a 100ml eggplant flask and add a mixed gas of ethylene and nitrogen (ethylene partial pressure 0.9 atm,
Combined with a container containing nitrogen partial pressure 0.1 atm) 1.5,
Ethylene was adsorbed at 20°C while stirring using a magnetic stirrer. During the initial 10 minutes of adsorption,
Using a BA-106T air pump manufactured by Iwaki Co., Ltd., the mixed gas was circulated and passed over the adsorbent. The amount of ethylene adsorption was determined by the gas brewing method.
Measured at 20°C.

The amount of ethylene adsorbed was 0.12 mmol after 10 minutes, and 1.2 mmol after 60 minutes.

That is, the adsorption of unsaturated hydrocarbons by activated carbon alone, which does not contain copper compounds, is significantly smaller than the adsorption by the solid adsorbent of the present invention.

Claims (1)

[Scope of Claims] 1 (i) Halide salt of copper () or copper oxide () and activated carbon, or (ii) Halide salt, carboxylate, sulfate, basic salt, or ammine complex salt of copper () or copper oxide A solid adsorbent for adsorption and separation of unsaturated hydrocarbons, consisting of ( ) and activated carbon. 2 (i) halide salt of copper () or copper oxide () and activated carbon, or (ii) halide salt, carboxylate, sulfate, basic salt or ammine complex salt of copper (), or copper () oxide and activated carbon A method for separating unsaturated hydrocarbons from a mixed gas, characterized by using a solid adsorbent composed of: