JPS61215209A - Separation of carbon monoxide - Google Patents

Abstract

PURPOSE:To save the initial cost and the operation energy for the separation of carbon monoxide from a mixed gas, by using an adsorbent composed of activated alumina impregnated with cuprous chloride and aluminum chloride. CONSTITUTION:An activated alumina carrier having the shape of sphere, honeycomb, plate, pipe, etc. is prepared beforehand. The carrier is impregnated with a solution obtained by dissolving cuprous chloride and aluminum chloride in a solvent, and the solvent is evaporated to obtain a solid carrier for the separation of carbon monoxide gas from a mixed gas containing the same.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for separating carbon monoxide. More specifically, the present invention relates to (a) CO recovery from co-containing gas (synthesis gas) obtained by partial oxidation or steam reforming of petroleum refinery offgas, heavy oil, coal, etc., (b) Il
c from coke oven gas, blast furnace gas and converter gas in ironworks
o Recovery (c) Removal of CO from underground gas in coal mines, etc., (d) C
It can be applied to removal of CO from exhaust gas containing O gold, and (e) recovery of CO from off-gas of ammonia production plants, etc.

As methods for separating and removing co from a co-containing gas, the cryogenic separation method and the liquid preparation cleaning method are well known. The cryogenic separation method liquefies and separates gases at low temperatures, so there is a problem in that energy costs and construction costs are high. On the other hand, the solution cleaning method is a method in which CO is absorbed by an aqueous solution of ammonia alkaline cuprous salt or hydrochloric acid acidic cuprous chloride, but there are problems with volatilization loss of ammonia and dissolution of CO1, or corrosion of equipment due to hydrochloric acid There are problems etc. Recently, a method of adsorbing and separating CO using activated carbon, zeolite, etc. has been studied, but the adsorption performance is poor and practicality is poor.As a way to solve this problem, a method of supporting copper salts on activated carbon (Japanese Unexamined Patent Publication No. 57 -8303 and JP-A-57-17785
9) has been proposed, but activated carbon has problems such as low strength and easy pulverization. In addition, because it easily adsorbs CO□, NH, hydrocarbons, sulfur compounds, etc. contained in the JJI feed gas, performance deterioration is likely to occur, and the purity of the recovered CO gas obtained during regeneration may also decrease. be.

Therefore, the present inventors have discovered a new C○ separation method that uses an adsorbent obtained by impregnating activated alumina with an organic solvent in which cuprous chloride and aluminum chloride are dissolved as a method that can solve these problems.

Carbon monoxide (hereinafter referred to as CO) is important as a raw material gas for chemical synthesis processes. Therefore, there is a need for a method for separating and recovering co from syngas obtained by partial oxidation of coal and petroleum or water gasification, steel plant off-gas, ammonia production plant off-gas, and the like. Further, since co is a harmful gas, it is required to be removed from exhaust gas from the viewpoint of environmental hygiene.

Many CO separation methods have been proposed so far, but all of them have had problems in terms of separation performance, economic efficiency, etc. The present invention provides a novel CO separation method that can solve these problems. The purpose is to

As a result of intensive research in order to achieve the above object, the inventor of the present invention has developed a carbon monoxide containing gas characterized by using a solid adsorbent consisting of cuprous chloride, aluminum chloride and activated alumina. It has been found that the above objects can be achieved by providing a method for separating carbon oxides.

The adsorbent of the present invention can be obtained by impregnating activated alumina with an organic solvent in which cuprous chloride and aluminum chloride are dissolved, and then straining to remove the solvent by a method such as reduced pressure or heating. As the organic solvent, aromatic organic solvents such as benzene, toluene, xylene, etc., or various organic solvents capable of dissolving the above-mentioned chlorides can be used. The activated alumina used as a carrier may be in any shape such as spherical, honeycomb, plate, pipe, or fiber, and those with a large specific surface area and pore volume are particularly preferred.

The amount of cuprous chloride and aluminum chloride supported in this adsorbent can be adjusted by using an organic solvent in which various amounts of these compounds are dissolved.
Since the adsorption capacity is small, per gram of activated alumina, chlorinated di-steel is.

0.5-5.0 mmo 41, aluminum chloride 0.
It is preferable to prepare it so that it becomes 5-5.0 mmoQ.

A method of adsorbing and separating Co in a Co-containing gas using the adsorbent of the present invention and recovering it as a high-purity Co gas will be described. Co can be selectively adsorbed by dehumidifying the Co-containing gas in advance and then bringing it into contact with a packed bed of the adsorbent. Although a low adsorption temperature is good, a large amount of cooling energy is required, and on the other hand, a suitable adsorption temperature is preferably 0 to 80°C since the amount of Co adsorbed becomes small at a high temperature. In addition, although atmospheric pressure is sufficient for adsorption pressure,
The higher the pressure, the greater the amount of C○ adsorption. However, if the adsorption pressure is high, the power required for compression increases, so it is usually 0~
10 kg/d is preferred.

The adsorbent that has adsorbed CO quickly desorbs Co by heating it to a temperature higher than the adsorption temperature, by keeping it at a pressure lower than the adsorption pressure, or by a combination thereof. By collecting this desorbed co, a high concentration of co can be recovered, and in some cases, this co can be oxidized and converted into harmless CO2, which can then be exhausted.

The adsorbent of the present invention is characterized by being inert to coexisting gases and having a high co adsorption capacity. Activated alumina, which is used as a carrier for this adsorbent, can be easily obtained in various shapes.

It is possible to easily prepare an adsorbent with an appropriate shape according to the properties of the target gas to be treated, and because it is strong, it does not have the problems of dust generation and adsorption bed blockage caused by powdering, unlike activated carbon. There are advantages.

Next, examples of the present invention are shown below, but the present invention is not limited thereto.

Example 1 Activated alumina particles of 3 mm diameter were immersed in a toluene solution containing cuprous chloride and aluminum chloride, stirred at 60°C for 4 hours under a N2 stream, the activated alumina was taken out, and the particles were soaked at 100°C in a N2 stream. The amount of cuprous chloride supported by drying is 3
．． An adsorption tower with an inner diameter of 47 mm was filled with 404 g of an adsorbent of 8 m■oQ/g activated alumina and aluminum chloride loading of 3.8 m+soQ/g activated alumina, and N2 gas containing 50% CO was charged at a temperature of 20°C. 0.833N per minute
The gas was passed through the gas at a rate of Q, and the change in C○ concentration in the outlet gas was measured. The obtained results are shown in FIG. 1(a). As a comparative example, the measurement results for only activated alumina are shown in Figure 1(b).
Shown below.

Example 2 The supported amount of cuprous chloride shown in Example 1 was 3.8 tsoQ/
gActivated alumina, aluminum chloride supported amount is 3.81o
Q /g0050% using activated alumina adsorbent,
c under the same conditions as in Example 1 by supplying a mixed gas of 10% Co, 10% H, and 30% N2.

After conducting the adsorption test, the adsorbent was regenerated at 100° C., and the adsorption and regeneration were repeated five times. The saturated amount of CO adsorbed by the adsorbent is shown in FIG. 2(a). or,
FIG. 2-(b) shows the saturated amount of CO adsorbed by the adsorbent when regeneration was performed after the sixth time under reduced pressure using a vacuum pump.

It can be seen that the adsorbent can be easily regenerated by either heating or depressurization method.

Furthermore, as a result of measuring the purity of CO gas recovered by the two regeneration methods, both methods showed high purity of 97 to 99%.

- As stated above, according to the carbon monoxide separation method of the present invention, operating energy can be saved, equipment costs can be reduced, and the adsorbent used has excellent durability and regeneration ability. I can see that it is something.

[Brief explanation of drawings]

FIG. 1(a) is a curve showing the relationship between the CO concentration in the gas and the operation time showing the performance of the activated alumina supporting cuprous chloride and aluminum chloride of the present invention, and FIG. 1(b) is a curve showing the relationship between the CO concentration in the gas and the operation time. It is a graph showing the relationship between co concentration and operation time in the case of only activated alumina. Figure 2 (a) shows the amount of C saturated adsorption when adsorption and temperature desorption are repeated five times, and Figure 2 (b) shows the co saturated adsorption amount when adsorption and pressure desorption are repeated five times. Indicate quantity. Patent applicant: Sumitomo Heavy Industries, Ltd. Karasu 1 Figure JP-A (min)

Claims (1)

[Claims] 1. A method for separating carbon monoxide from a carbon monoxide-containing gas, which is characterized by using a solid adsorbent consisting of cuprous chloride, aluminum chloride, and activated alumina.