JPS61164642A - Carbon monoxide absorbent - Google Patents

Abstract

PURPOSE:To eliminate the clogging of an absorbent packed part at the time of the passage of dust-containing gas, by forming a carbon monoxide absorbent by using copper halide and activated carbon as constitutional components and molding both components into a monolithic shape. CONSTITUTION:A monolithic shape molded body containing activated carbon as a constitutional component and having gas flow channels (a) is immersed in a solvent containing copper halide. Next, said solvent is stirred and subsequently removed by vacuum distillation to obtain a carbon monoxide adsorbent. The compounding ratio of activated carbon to copper halide is about 1-30, pref., about 3-5 on a wt. ratio basis. As copper halide, there are copper (I) chloride, copper (I) fluoride, copper (I) bromide, copper (II) chloride, copper (II) fluoride or copper (II) bromide. As the solvent, water, an aqueous hydrochloric acid solution, benzene, toluene, propionitryle or acetonitryle are used.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is for separating carbon monoxide from a mixed gas containing nitrogen, oxygen, methane, carbon dioxide, hydrogen, etc. The present invention relates to a solid absorbent used for.

(Prior Art) Carbon monoxide is a basic raw material in synthetic chemistry, and is produced from coke or coal using a generating furnace, a water gas furnace, a Winkler furnace, a Lurgi furnace, a Kotspers furnace, etc. It is also produced from natural gas, petroleum expanded hydrogen, and steam reforming and partial oxidation methods. In these methods, the product is obtained as a mixed gas of -R oxide, hydrogen, carbon dioxide, methane, nitrogen, etc. For example, in the case of aqueous scum, - 4-5% carbon oxide, 5% LO% methane α, 4% nitrogen
~9% composition, typically 1000-2000 pp!
Contains 11 aquariums.

Carbon monoxide, which is produced as a by-product in steel mills, oil refineries, and petrochemical plants, is also obtained as a mixed gas.

In order to use carbon monoxide as a raw material for synthetic chemicals, it is necessary to separate the 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 from the hydrocarbon dehydrogenation process, but a small amount of carbon monoxide often contains. This-
Since carbon oxide acts as 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 the mixed residue. In the solution cleaning method, a mixed gas is pressurized to 150 to 200 atm at room temperature and absorbed into an ammoniacal aqueous solution of copper formate (1) or a hydrochloric acid suspension of copper chloride (1), and carbon monoxide is separated and removed. Next, 19-carbon oxide is released and separated by heating this prepared liquid under reduced pressure, and the prepared liquid is regenerated. However, it is difficult to handle the liquid absorbent, and it causes corrosion of the equipment and loss of solution. However, it has disadvantages such as difficulty in operation management to prevent precipitation, and high pressure construction costs.

According to British Patent No. M1,318,790, a toluene solution of copper aluminum tetrachloride (0u(AtC4)), when brought into contact with a gas mixture containing 50 mol of carbon monoxide at 25°C, produces -dispersed carbon. It is said that 95% of carbon monoxide can be recovered by absorbing water and heating it to t-80°C. This absorption liquid absorbs the hydrogen and carbon dioxide contained in the mixed gas.
Although it has the advantages of being unaffected by methane, nitrogen and oxygen and having a low absorption pressure, it reacts irreversibly with water, resulting in deterioration of absorption capacity, formation of precipitates, and generation of hydrochloric acid. . For industrial implementation, water in the gas mixture
;[Must be strictly controlled to below lppm. Therefore, a strong dehydration process of the mixed gas is required before the absorption process, and strict control is essential. Note that copper aluminum tetrachloride reacts strongly with water and irreversibly loses its ability to absorb single-layer carbon, so even if it is brought into contact with a mixed gas containing 1 ppm of water, the amount of mixed gas processed will be reduced. Not only does the amount of deactivation 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 using this absorption liquid, it is unavoidable that toluene vapor will be mixed into the recovered carbon nine oxide, and a device to remove this toluene is required. It has disadvantages such as being subject to process constraints when used.

Solving the disadvantages of the above carbon monoxide separation method using a toluene solution of copper aluminum tetrachloride (0u(AtC4)), a solid absorbent composed of halogenated steel and activated carbon was used as a carbon oxide separation method. The carbon monoxide absorbent used is known (Japanese Patent Laid-Open No. 156517/1983). In this method, carbon monoxide is rapidly absorbed when the solid absorbent is brought into contact with a mixed gas containing a dispersion carbon tube at around room temperature, and then the absorbent is heated to a certain temperature or - Carbon monoxide can be easily released by reducing the carbon partial pressure tube.

(Problems to be Solved by the Invention) However, the solid absorbent composed of halogenated steel and activated carbon proposed in the above-mentioned Japanese Patent Application Laid-open No. 58-156517 has a large pressure loss and cannot handle a mixed gas containing dust. The drawback is that if it is allowed to pass through, the absorbent loading section may become clogged.

Therefore, the present invention has the following advantages: - Pressure loss is small when the mixed gas from which carbon monoxide is to be separated is passed through the carbon oxide separator, and even when the mixed gas containing dust is passed through, the absorbent loading section is blocked. It is an object of the present invention to provide a solid absorbent that satisfies all of the following conditions: no carbon monoxide separation occurs, and it is easy to handle when loaded into a carbon monoxide separator.

(Means for solving all the problems) In other words, the present invention is based on the fact that the absorbent is made into a monolith shape.
- A carbon monoxide absorbent is characterized in that it is a solid consisting of halogenated steel and activated carbon and has a monolith shape.

The monolith shape that the carbon monoxide absorbent of the present invention should have is the shape of a single body, for example, a plate, a cylindrical honeycomb, which can provide a gas flow path by one or more combinations. This corresponds to shapes such as

Specific examples of monolith shapes include, for example, Figures 1 and 2.
There are those shown in Figures 1 and 3. In Figures 1 and 2 and Figure 3, (a) is the gas flow path. In addition,
Figure 1, Figure 2 and #! FIG. 3 is merely an illustration of the shape of the carbon monoxide absorbent of the present invention, and the shape of the carbon monoxide absorbent of the present invention is not limited to these.

The carbon monoxide absorbent of the present invention can be produced by, for example, immersing a monolith-shaped molded body containing activated carbon in a solvent containing norogenated steel, stirring the liquid, and then removing the solvent under reduced pressure and distilling it. 19 is obtained by removing it by a method such as removal.

The norogenated steel used in the carbon monoxide absorbent of the present invention includes, for example, copper chloride (I), copper fluoride (1), copper bromide (1), copper chloride (1), copper fluoride (1), Copper(II)
These include manufactured copper(II) bromide.

The solvent used for preparing the carbon monoxide absorbent of the present invention is
Examples include water, basic aqueous solutions, benzene, toluene, propionitrile, and acetonitrile.

Regarding the composition of the carbon monoxide absorbent of the present invention, the weight ratio of activated carbon to halide is 1 to 30, preferably 3 to 5.

The carbon monoxide absorbent of the present invention absorbs -carbon oxide at 0 to 40°C under normal pressure, and then the absorbent is heated to 60°C or higher, the pressure is reduced, or -carbon oxide is absorbed into the carbon monoxide absorbent of the present invention. By lowering the pressure19, the absorbed carbon monoxide can be released.

On the other hand, the carbon monoxide absorbent of the present invention is stable against a mixed gas containing water, and its carbon monoxide absorption capacity hardly decreases even after contact with a nitrogen stream containing water.

Furthermore, since the carbon monoxide absorbent of the present invention has a precise monolithic shape as illustrated in FIGS. 1 and 2 and FIG. The pressure loss is small when a mixed gas containing carbon absorbent is passed through, and the absorbent loading section does not get clogged even when a mixed gas containing dust is passed through. It has the characteristic of being easy to handle.

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

Example 1 A carbon monoxide absorbent according to the present invention was prepared in the following manner. First, commercially available coal-based granular activated carbon (average particle size 1.01111%
Specific surface area 1150 m”/f)
The powder was classified to 0 μm or less, spread to a grain size of 1 μm or less, and then mixed into clay (25 tons of New Zealand kaolin), added with 100 g of water, and kneaded for 2 hours using a kneader. This mixture was extruded and dried at 60°C for 6 hours, then baked at 1000°C for 2 hours under nitrogen.
An elaborate monolith shaped molded body as shown in Fig. 4 was obtained. In addition, the fourth
Dimensions (1), (21, (31) and (4) in the figure are 1■, 15■, 38■ and 60■, respectively. However, the nine gas flow paths drawn in Figure 4 are , the number in (a) is different from the actual number.Next, under dry nitrogen, in a separable flask with an internal volume of 500 m, commercially available reagent first grade chlorinated steel (1) was added.
Add 2.7 t (27.5 mmol Jf) of hydrochloric acid, a first-grade commercially available reagent diluted to 50% with purified water, and stir at room temperature for 1 hour while stirring using a magnetic stirrer.
I left it for a while. The above-mentioned monolith-shaped molded product, which had been dried at 180°C for 4 hours under dry nitrogen and a reduced pressure of 6wx Ht, was placed in this separable flask, and the flask contents were stirred at room temperature for t−1 hours. Step 9: Water and hydrogen chloride were sufficiently removed by reducing the pressure in the flask to t''6 gHf and heating and keeping it at 100° C. to obtain a -carbon oxide absorbent.

A cylindrical container with the above-mentioned carbon monoxide absorption capacity, a square cross section of 40 cm on a side, and a length of 100 m is loaded in such a way that gold gas passes only through the lattice of the absorbent, and the cylindrical container t −
A mixed gas of 1 atm of carbon monoxide and nitrogen (-carbon oxide partial pressure α8 atm, nitrogen cumulative partial pressure (L2 atm) 5 jt) is combined with the next container and absorbed while circulating the mixed gas using an air pump at room temperature. The sample was brought into contact with the agent to absorb carbon oxide.The amount of carbon oxide absorbed was measured using the gas burette method.

- absorption of carbon oxide is rapid, after 3 minutes 11,5
gmol of carbon monoxide was absorbed, and the carbon monoxide absorbent after 60 minutes was 21.1 gmol, almost reaching the equilibrium absorption amount.

Next, this absorbent was heated to 120°C at 1 atm, and -
The amount of carbon oxide released was measured by the gas burette method. - Carbon oxide is released rapidly, the amount released is 2 after 10 minutes.
It reached 1.1 mmol. Analysis of the released gas using a gas chromatograph revealed that the released gas was only carbon monoxide and no other components were detected.

Cylinder reactor loaded with absorbent after cooling atm
Mixed gas of carbon monoxide and nitrogen (-carbon partial pressure 118
At room temperature, the mixed gas is circulated using an air pump and brought into contact with the absorbent to absorb carbon oxide.

- absorption of carbon oxide is rapid, after 5 minutes 1 t 9
gmol of carbon monoxide was absorbed, and after 60 minutes the carbon monoxide absorbent amounted to 21.1 mmol, almost reaching the equilibrium absorption amount.

When this absorbent is heated to 120 °C at 1 atm, -carbon oxide is rapidly released, with a release t of 21.1 after 10 minutes.
mmol was reached.

Thereafter, even if the above-mentioned operation was repeated, no change in carbon oxide absorption rate or absorption amount was observed.

After that, the cylindrical container f 1 containing this carbon oxide absorbent
1 atm nitrogen gas containing 60 mW (a 9 m!non) water (water concentration 11,000 ppm
) 2011, and the water-containing nitrogen gas was circulated using an air pump and brought into contact with the carbon monoxide absorbent for 10 minutes at room temperature.

Next, a mixed gas of carbon monoxide and nitrogen (-carbon oxide partial pressure α8 atm) in this cylindrical container t1 atm.

The mixed gas is connected to a nitrogen partial pressure α2 atm) S t f ratio container and brought into contact with an absorbent while circulating the mixed gas using an air pump at room temperature to absorb carbon oxide. The absorbent absorbs carbon monoxide quickly, and after 60 minutes, the amount of carbon monoxide absorbed is 21.1 rnmo1, reaching the equilibrium absorption amount and leaving the skin. That is, the absorption rate and absorption amount of carbon oxide hardly change even when the absorbent f is brought into contact with a gas containing 11,000 ppm of water.

Then, when heated to 120°C with this absorbent t1atm, -carbon oxide is rapidly released, and the released amount is 2 after 10 minutes.
It reached 1.1 mmol.

Example 2 A nona-carbon oxide absorbent prepared in the same manner as in Example 1 was placed in a cylindrical container with a square cross section of 40 m on each side and 100 m in length, with gas passing only through the lattice of the absorbent. This cylindrical container was charged with a mixed gas of 1 atm carbon monoxide and nitrogen (-European carbon partial pressure 18 atmSiii cumulative partial pressure 12
Atm) S L was connected to a container, and the mixed gas was brought into contact with the absorbent at room temperature while being circulated using an air pump tube to absorb carbon oxide. The amount of carbon oxide absorbed was measured using the gas burette method.

Carbon monoxide absorption is rapid, with 11,9
Wtmol of carbon monoxide was absorbed, and the amount of carbon monoxide absorbed after 60 minutes was 21.1 gmol, almost reaching the equilibrium absorption amount.

Next, use a vacuum pump to reduce the pressure (6 varHf) inside the cylindrical container containing this carbon oxide absorbent at room temperature for 10 minutes.
) to release the absorbed carbon monoxide.

Thereafter, this cylindrical container was heated to 1 atm of a mixed gas of carbon monoxide and nitrogen (-carbon oxide partial pressure α8 atm).

N partial pressure llL2 atm) Stt is combined with a ratio container,
At room temperature, the mixed gas was brought into contact with an absorbent while being circulated using an air pump to absorb -carbon oxide t-.

The absorption of carbon monoxide is rapid, after 5 minutes I Z 6
mmol of carbon oxide was absorbed, and the amount of carbon monoxide absorbed after 60 minutes was 21.1 mmol, almost reaching the equilibrium absorption amount.

Thereafter, even if the above-mentioned operation was repeated, no change was observed in the carbon oxide absorption rate and absorption amount.

After that, the cylindrical container containing this carbon oxide absorbent was
1at containing 0 mW (a 9 mmof ) of water
m (D Nitrogen gas (water concentration 11,000 ppm
) 20t1 (connected to a storage vessel and at room temperature, the water-laden gas was circulated using an air pump and brought into contact with the carbon monoxide absorbent for 10 minutes.

Next, a mixed gas of carbon oxide and nitrogen (-carbon oxide partial pressure α8 atm) in this cylindrical container t-1 atm.

It was connected to a container containing nitrogen partial pressure (L 2 atm ) 51 and brought into contact with an absorbent at room temperature while circulating the mixed gas using an air pump to absorb -carbon oxide. The absorbent quickly absorbs carbon monoxide, and the amount of carbon monoxide absorbed after 60 minutes is 21.1 mmo1, reaching the equilibrium absorption amount. , the absorbent t- did not change much when contacted with Gisu containing 11,000 ppm of water.

Example 3 The same activated carbon as in Example 1 was treated by the method described in Example 1 to obtain a monolith-shaped body tube similar to that in Example 1. Next, under dry nitrogen, 4.6 ml of commercial reagent special grade steel chloride (1) dihydrate was added to a Sepa 2-pul flask with an internal volume of 50 (ld).
f (27, Ommol) and purified water 50Q+d
The mixture was left at room temperature for 1 hour while stirring using a magnetic stirrer. Into this separable flask, put the above-mentioned monolith-shaped molded product that had been dried at 180°C for 4 hours under dry nitrogen and a reduced pressure of 6 mHf, and stir the contents of the flask at room temperature for 1 hour. The pressure inside the flask was reduced to t-6 vmHf, and the flask was heated and kept at 100° C., and water was sufficiently distilled off to obtain a carbon oxide absorbent.

The above carbon monoxide absorbent was loaded into a cylindrical container with a square cross-section of 40 cm on a side and a length of 100 cm, so that the gas could pass only through the lattice of the absorbent. 1 container
Mixed gas of carbon monoxide and nitrogen atm (-carbon oxide partial pressure (L8 atm), nitrogen partial pressure (L 2 atm) 5
The mixed gas was connected to a container containing L f and brought into contact with the absorbent at room temperature while completely circulating the mixed gas using an air pump to absorb -carbon oxide. The amount of carbon oxide absorbed was measured using the gas burette method.

-The absorption of carbon oxide is rapid, after 5 minutes 6.4? P
1 mob of carbon monoxide was absorbed, and the carbon monoxide absorption amount after 60 minutes was 9.6 mmol, almost reaching the equilibrium absorption amount.

Next, this absorbent was heated to 120°C with t-1atm, and -
Measure the amount of carbon oxide released using the total gas burette method. - Carbon oxide is released rapidly, the amount released after 10 minutes is 9
．． It reached 6 mmol. Analysis of the released gas using a gas chromatograph revealed that the released gas was only carbon monoxide.
No other components were detected.

After cooling, the cylindrical reactor loaded with the absorbent was heated again to 1 atm.
Mixed gas of carbon monoxide and nitrogen (-carbon oxide partial pressure 18a
tm, 9 elemental partial pressure llL2atm) 5tt'', and brought into contact with the absorbent at room temperature while circulating the mixed gas using an air pump to absorb -carbon oxide.

- absorption of carbon oxide is rapid, after 3 minutes 6.5 m
mol of carbon monoxide was absorbed, and the amount of carbon monoxide absorbed after 60 minutes was 9.6 mmol, almost reaching the equilibrium absorption amount.

When this absorbent is heated to 120°C at 1 atm, -carbon oxide is rapidly released, with the amount released being 9.6% after 10 minutes.
m mol was reached.

Thereafter, even if the above operation was repeated, no change was observed in the absorption rate or amount of carbon oxide absorption.

Thereafter, this skin-type container'f of the carbon oxide absorbent:
1a containing 160 mf (& 9 mmol of water)
tmO￥i1 Cumulative gas (water concentration 11,000ppm)2
At room temperature, the water-containing nitrogen gas is circulated and brought into contact with the carbon monoxide absorbent for 10 minutes at room temperature.

Next, a mixed gas of carbon monoxide and nitrogen (-carbon oxide partial pressure [L8 atm.

The mixture was connected to a container containing nitrogen partial pressure (L 2 atm ) 5 tt, and brought into contact with an absorbent at room temperature while circulating the mixed gas through an air pump to absorb carbon oxide. Carbon monoxide was quickly absorbed by the absorbent, and the amount of carbon monoxide absorbed after 60 minutes was 9.6 mmol, almost reaching the equilibrium absorption amount. That is, the absorption rate and amount of carbon oxide hardly changed even when the absorbent was brought into contact with a gas containing 11,000 ppm of water.

Example 4 Same as Example 5! ! MIMI, a carbon monoxide absorbent, has a cross-sectional shape of a square with a side of 4 OwI+ and a length of 100 mm.
A mixed gas of carbon monoxide and nitrogen (- carbon oxide partial pressure α8 atm, nitrogen partial pressure ( L 2 atm ) 5 t was combined with a container containing L 2 atm ) 5 t, and the mixed gas was brought into contact with the absorbent while circulating it using an air pump at room temperature to absorb carbon oxide. The amount was measured using the gas burette method.

Absorption of m-carbon oxide is rapid and after 69.5 minutes, 6,41
mmol of carbon monoxide was absorbed, and the amount of carbon monoxide absorbed after 60 minutes was 9.6 fi mo:t, almost reaching the equilibrium absorption amount.

Next, using a vacuum pump, the pressure inside the cylindrical container containing the carbon oxide absorbent was reduced to 6 HP at room temperature for 10 minutes to release the absorbed carbon monoxide.

Thereafter, a mixed gas of carbon monoxide and nitrogen (-carbon oxide partial pressure α13 atm) in this cylindrical container t-1 atm.

The mixed gas was connected to a container containing a nitrogen partial pressure of 12 atm) 5 Lf, and brought into contact with an absorbent while circulating the mixed gas using an air pump at room temperature to absorb -carbon oxide.

The absorption of carbon monoxide is rapid, and after 3 minutes, the amount of carbon monoxide is +6 mm
1 of carbon monoxide is absorbed, and the amount of carbon monoxide absorbed after 60 minutes is 9.6 yBmol, which almost reaches the equilibrium absorption amount.

After that, even if the above operation was repeated, there was no change in the absorption rate or amount of carbon oxide absorption.

After that, this cylindrical container containing the carbon oxide absorbent t”
1 atmO1 containing 160 mf (a ? mmol) of water! Elementary gas (concentration of water 11.ooOppm
) 20tf: It was combined with the container containing it, and the water-containing nitrogen gas was circulated using an air pump at room temperature and brought into contact with the carbon monoxide absorbent for 10 minutes.

Next, carbon monoxide in this cylindrical container tIatm and ti!
Mixed gas (-carbon oxide partial pressure (L8atm).

The mixed gas is connected to a container containing nitrogen partial pressure α2 atm) 5 tf, and brought into contact with an absorbent while circulating the mixed gas using an air pump at room temperature to absorb carbon oxide. The absorbent quickly absorbed all of the carbon monoxide, and the amount of carbon monoxide absorbed after 60 minutes was ρ6fnmol, almost reaching the equilibrium absorption amount. That is, - the rate and amount of absorption of carbon oxide depends on the absorbent? Even when brought into contact with a gas containing 11,000 ppm of water, there was no change at all.

Example 5 A total of 15 carbon monoxide absorbents of the present invention prepared in the same manner as in Example 1 were placed in a cylindrical container with a cross-sectional shape of 4 squares on each side (1 m + square, length 1 m). The cylindrical container was loaded so that gas could only pass through it, and nitrogen was continuously passed through this cylindrical container to examine the relationship between gas flow rate and pressure loss.On the other hand, for comparison, the cylindrical container mentioned above A container was filled with glass beads having a diameter of 51 m1, nitrogen was continuously flowed through the cylindrical container, and the relationship between gas flow rate and pressure loss was determined.

When nitrogen is passed through the carbon monoxide absorbent of the present invention at room temperature, what is the gas flow rate and gas flow direction at the absorbent loading section? P
Figure 5 (A) shows the relationship between the pressure drop per I and the gas flow rate and gas flow direction in the packed bed when nitrogen is passed through a packed bed of glass beads with a diameter of 5 cm at room temperature. The relationship between the pressure loss and the pressure loss is shown in CB in the t-ms diagram. The pressure loss at the same gas flow rate is smaller when the carbon monoxide absorbent of the present invention is loaded, and it is clear that the monolith shape is advantageous in reducing the pressure loss during gas passage.

[Brief explanation of drawings]

1, WC2, and 5 are diagrams illustrating the monolith shape. FIG. 4 is a diagram specifically showing the shape of an extrusion molded product obtained in the process of preparing the carbon monoxide absorbent of the present invention, as described in Example 1. FIG. 5 is a diagram showing the relationship between gas flow velocity and pressure loss. Figure 1 Figure 2 Figure 3 Horse Figure 4

Claims (1)

[Claims] A carbon monoxide absorbent characterized by being a solid comprising copper halide and activated carbon as constituent components and having a monolith shape.