KR101681081B1 - Oxidation catalyst for carbon monoxide at low temperature - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to a composite catalyst body for carbon monoxide oxidation reaction in which carbon monoxide (CO) is oxidized at a low temperature of 100 ° C or lower and a method for producing the composite catalyst body, and a composite oxide catalyst comprising manganese, copper (Cu) and cobalt The support is supported by a binder. The carbon monoxide conversion reaction composite catalyst body is characterized in that carbon monoxide conversion is carried out in air containing water (H ₂ O) at a carbon monoxide conversion rate of 80% or more at 50 ° C to 100 ° C and 0 to 4.2 Vol% .

Description

TECHNICAL FIELD [0001] The present invention relates to a low temperature carbon monoxide oxidation catalyst,

The present invention relates to a composite catalyst body, and more particularly, to a composite catalyst body for a low-temperature carbon monoxide oxidation reaction and a production method thereof.

Generally, carbon monoxide is a toxic substance contained in combustion exhaust gas. In particular, prolonged exposure to carbon monoxide in an enclosed space may cause hypoxia. Therefore, carbon monoxide must be removed before exhausting the combustion exhaust gas from the space where carbon monoxide is generated.

The prior art uses a method of oxidizing carbon monoxide and oxygen using an adsorbent or a catalyst to remove carbon monoxide in the combustion exhaust gas. The adsorbent includes activated carbon having high specific surface area, zeolite, and the like. The adsorbent shows high carbon monoxide removal performance at the beginning of the oxidation reaction. However, the adsorption capacity of the adsorbent quickly reaches a saturated state, and the adsorbent once used can not be reused.

In addition, the catalyst for removing carbon monoxide causes an oxidation reaction between oxygen and carbon monoxide on the surface, and has a relatively long life and is easy to be reused as compared with the adsorbent. The catalyst for removing carbon monoxide may carry a noble metal such as platinum (Pt) or palladium (Pd) on a metal oxide support such as alumina (Al ₂ O ₃ ) or titania (TiO ₂ ). However, the carbon monoxide removing catalysts have an effect of removing carbon monoxide at a temperature of at least 100 ° C., and are completely removed at a temperature of 150 ° C. or higher. Therefore, an additional process for increasing the temperature of the catalyst for removing carbon monoxide to the oxidation reaction temperature is required. In addition, the noble metal is an expensive material, and a highly dispersing technique is additionally required when used as a catalyst. Also, deterioration of the catalyst performance due to deterioration of the noble metal should be solved.

In order to overcome the above-described limitations, the prior art is developing a catalyst in which a carbon monoxide oxidation reaction occurs at a low temperature using Hopkarite. Korean Patent Laid-Open No. 10-2012-0096171 has developed a catalyst for low-temperature oxidation using a potassium-platinum-palladium active species as a catalyst on a hopcalite catalyst of copper (Cu) -manganese (Mn). However, Hopkarite catalysts are relatively economical and have a good ability to remove carbon monoxide, but generally have a property of reducing the reaction activity in the presence of water.

Korean Patent Publication No. 10-2012-0096171

An object of the present invention is to provide a composite catalyst for carbon monoxide oxidation reaction which is capable of oxidation reaction of carbon monoxide (CO) at a low temperature of 100 ° C or lower and can be activated even in an environment containing moisture, and a process for producing the same.

The composite catalyst for a carbon monoxide oxidation reaction according to the present invention includes a support in which a composite oxide catalyst prepared from a manganese (Mn) precursor, a copper (Cu) precursor and a cobalt (Co) precursor is supported on a support by a binder.

 In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the mole ratio of the complex oxide catalyst may be Mn: Cu: Co = 1: 0.01-0.5: 0.01-0.5 have.

In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the support may be a carbon monolith or the like.

In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite catalyst body may include 1 to 20% by weight of a composite oxide catalyst.

In the composite catalyst for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite oxide catalyst may be coated or impregnated on a support using a binder selected from an inorganic binder or an organic binder.

In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite catalyst body may further include a palladium precursor.

In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composition ratio of manganese and palladium in the composite catalyst body may have a molar ratio of manganese: palladium = 1: 0.01-0.05 to each precursor.

In the composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite catalyst body may have a carbon monoxide conversion of 80% or more in a range of 50 ° C to 100 ° C.

The method for preparing a composite catalyst for a carbon monoxide oxidation reaction according to an embodiment of the present invention includes the steps of mixing a mixture containing a manganese (Mn) precursor, a copper (Cu) precursor, and a cobalt (Co) precursor to form a composite oxide catalyst , Drying the composite oxide catalyst at 60 ° C to 100 ° C, firing the dried composite oxide catalyst at 200 ° C to 400 ° C, coating the fired composite oxide catalyst with a binder on the surface of the support, And drying the composite catalyst body at 60 ° C to 100 ° C.

 The method for preparing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention may further include washing coating an aqueous solution of a palladium precursor on the composite catalyst body.

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composition ratio of manganese and palladium in the composite catalyst body may have a molar ratio of manganese: palladium = 1: 0.01 to 0.05 based on the precursor.

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the molar ratio of the complex oxide catalyst may be Mn: Cu: Co = 1: 0.01-0.5: 0.01-0.5 based on the precursor .

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the support may be a carbon monolith.

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite catalyst body may include 1 to 20 wt% of the composite oxide.

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the binder may include an inorganic binder or an organic binder.

In the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to an embodiment of the present invention, the composite catalyst body may have a carbon monoxide conversion of 80% or more in a range of 50 ° C to 100 ° C.

The catalyst for carbon monoxide oxidation reaction according to the present invention can effectively remove CO by oxidizing carbon monoxide to carbon dioxide at a low temperature of 100 ° C or lower and can be regenerated by simple heat treatment even when moisture is present. It can be used for domestic and industrial applications.

FIG. 1 is a view showing the results of CO conversion versus temperature according to Example 1 of the present invention. FIG.

Hereinafter, the composite catalyst body for carbon monoxide oxidation reaction of the present invention and its production method will be described in detail. Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

The composite catalyst for a carbon monoxide oxidation reaction according to the present invention includes a support in which a composite oxide catalyst prepared from a manganese (Mn) precursor, a copper (Cu) precursor and a cobalt (Co) precursor is supported on a support by a binder.

More specifically, the complex oxide catalyst may be a transition metal composite oxide and may replace gold (Au) and platinum (Pt) used in the prior art. In addition, the complex oxide catalyst contains manganese, copper (Cu), and cobalt (Co), so that the carbon monoxide oxidation reaction can be effectively performed at a low temperature of 100 ° C or lower. The composite catalyst according to an embodiment of the present invention contains manganese, copper (Cu), and cobalt (Co), so that carbon monoxide conversion exhibits a remarkable effect of 80% or more at a carbon monoxide oxidation reaction temperature in the range of 50 ° C to 100 ° C, 100% < / RTI > in the range of < RTI ID = 0.0 > 100 C < / RTI >

The molar ratio of the complex oxide catalyst may be Mn: Cu: Co = 1: 0.01-0.5: 0.01-0.5 based on the precursor, and Mn: Cu: Co = 1: 0.1-0.2: 0.05 to 0.1 may be more preferable. The activity of the composite catalyst for carbon monoxide oxidation reaction may be varied depending on the molar ratio at a low temperature. In particular, it shows a specific effect that the CO conversion of the composite catalyst body can be improved in an environment containing water (H ₂ O) by the molar ratio. According to a specific embodiment, the composite catalyst body having the above-mentioned molar ratio of the composite oxide catalyst has a specific activity having a CO conversion of 35% to 45% even if it contains up to 3% of water.

And baked at 200 ° C to 400 ° C for 3 hours to 4 hours, and then pelletized to have a size of 0.1 to 1000 μm, preferably 50 to 800 μm, more preferably 100 to 500 μm. The composite oxide catalyst can increase the particle size through pressurization. Increasing the particle size facilitates coating on the support and increases the coating amount of the composite oxide catalyst.

The composite oxide catalyst may require a catalyst forming process for use in an actual process. Therefore, the composite oxide catalyst is coated on the support to produce a composite catalyst body. The support facilitates heat transfer to the composite oxide catalyst. In addition, various structures of the support allow dispersing the composite oxide catalyst to ensure high specific surface area. And the support may be capable of a high flow rate reaction due to the rigid structure of high strength components. The support is preferably a carbon monolith, but is not limited thereto.

The composite catalyst body may preferably contain 1 to 20 wt% of the composite oxide catalyst, and more preferably 5 to 10 wt% of the composite oxide catalyst. The activity of the composite catalyst body for carbon monoxide oxidation reaction may vary according to the amount of the composite oxide catalyst. Specifically, when the amount of the composite oxide catalyst is small, the activity of the composite catalyst body for carbon monoxide oxidation reaction is greatly reduced.

And the coating of the composite oxide catalyst on the support is carried out via the binder. The binder includes an inorganic binder or an organic binder. The inorganic binder may include clay, water glass, silica, titania, zirconia. The organic binder may include a polyvinyl alcohol, a polyurethane, an acrylic resin, a melamine resin or an epoxy resin. The binder may be used in an aqueous solution by mixing with water. The aqueous solution may contain 5 wt% to 15 wt% of a binder, and may be used in an amount of 5 to 20 wt parts based on 100 wt parts of the composite catalyst. However, It does not.

The composite catalyst may further include a palladium precursor. If the complex oxide catalyst contains a palladium precursor, the catalytic activity can be greatly increased. In the composite catalyst body containing the palladium precursor, the carbon monoxide oxidation reaction can be greatly improved in an environment containing moisture compared to the complex oxide catalyst. According to an embodiment of the present invention, the catalyst containing the palladium precursor may have carbon monoxide conversion of 40% to 60% in an environment containing 5 vol% of water (H ₂ O). In addition, the composite catalyst body containing the palladium precursor can realize excellent durability performance without being affected by deterioration due to the carbon monoxide oxidation reaction temperature in the long term even in the presence of moisture. For example, even when the oxidation reaction is continuously performed for 600 minutes or more in the state of containing water, excellent performance without deterioration of activity is exhibited.

The composite catalyst preferably has a molar ratio of manganese: palladium = 1: 0.01 to 0.5 based on the precursor, and more preferably has a molar ratio of manganese: palladium = 1: 0.03 to 0.05.

 The method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to the present invention includes the steps of forming a composite oxide catalyst by stirring a mixture containing a manganese (Mn) precursor, a copper (Cu) precursor and a cobalt (Co) precursor, Drying the catalyst at 60 ° C to 100 ° C, firing the dried composite oxide catalyst at 200 ° C to 400 ° C, coating the fired composite oxide catalyst with a binder on the surface of the support to form a composite catalyst body And drying the composite catalyst body at 60 ° C to 100 ° C.

The composite catalyst body is manufactured from a manganese (Mn) precursor, a copper (Cu) precursor and a cobalt (Co) precursor and exhibits a remarkable effect of 80% or more at a carbon monoxide oxidation reaction temperature in the range of 50 ° C to 100 ° C, Lt; RTI ID = 0.0 > 100 C < / RTI >

An embodiment of the present invention is as follows. The manganese-copper-cobalt composite oxide catalyst produced by oxidation-reduction reaction of potassium permanganate, manganese acetate, copper precursor and cobalt precursor is washed using distilled water and ethanol.

The copper precursor may include copper nitrate, copper acetate, copper chloride, and copper nitrate may be selected.

The cobalt precursor is preferably selected from cobalt nitrate, but it is not limited as long as it can form a manganese-copper-cobalt composite oxide catalyst.

As described above, the mole ratio of the manganese-copper-cobalt composite oxide catalyst to the complex oxide catalyst is preferably 1: 0.01 to 0.5: 0.01 to 0.5 in terms of Mn: Cu: Co based on the precursor, , Mn: Cu: Co = 1: 0.1 to 0.2: 0.05 to 0.1.

The dried manganese-copper-cobalt composite oxide catalyst is calcined at 200 ° C. to 400 ° C. for 3 hours to 4 hours, and thereafter is dried to a size of 0.1 μm to 1000 μm, preferably 50 μm to 800 μm, more preferably 100 μm to 500 μm Pelletizing to have. The content of the calcined manganese-copper-cobalt composite oxide catalyst is as described in the description of the complex oxide catalyst.

The calcined manganese-copper-cobalt composite oxide catalyst is coated on a support by a binder.

The description of the support and the binder is the same as or similar to that described for the complex oxide catalyst.

In addition, the palladium precursor may be coated on the composite catalyst body to increase the catalytic activity. Therefore, the method for producing a composite catalyst body for a carbon monoxide oxidation reaction according to the present invention may further comprise wash coating the aqueous solution of the palladium precursor with the composite catalyst body. The wash coating of the palladium precursor aqueous solution may be performed after the composite oxide is coated on the support and dried.

The composite oxide catalyst coating layer formed on the surface of the composite catalyst body may further include a trace amount of palladium precursor to greatly increase catalytic activity in an environment containing moisture. The composite catalyst preferably has a molar ratio of manganese: palladium precursor = 1: 0.01 to 0.05 based on the precursor, and more preferably has a molar ratio of 1: 0.03 to 0.05.

As described in the description of the composite oxide catalyst, the composite catalyst body includes 1 to 20 wt% of the composite oxide catalyst.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. It is to be understood that the present invention is not limited by the examples and the comparative examples presented herein.

[Example 1]

The manganese - copper - cobalt composite oxide catalyst for carbon monoxide oxidation reaction was synthesized by precipitation method.

8.532 g of potassium permanganate is dissolved in 50 g of demineralized water. At the same time, 20.250 g of manganese acetate, 3.672 g of copper nitrate and 2.031 g of cobalt nitrate were dissolved in 50 g of demineralized water for 1 hour. Thereafter, an aqueous solution of potassium permanganate is slowly dropped into a mixed aqueous solution of manganese acetate, copper nitrate, and cobalt nitrate and mixed for 24 hours. The mixed precipitate was washed and filtered with 2000 g of demineralized water and 1000 g of ethanol, and then dried at 100 ° C for 12 hours. The dried product was calcined at 300 DEG C for 2 hours in an air atmosphere.

The calcined and pelletized manganese-copper-cobalt composite oxide catalysts were selected to have a size of 250 to 425 μm.

The carbon monolith support was soaked in an aqueous solution of 15 wt% poly (vinyl alcohol) (ALDRICH, 99 +% hydrolyzed, PVA) in order to coat the composite catalyst on the carbon monolith support. The selected manganese - copper - cobalt composite oxide catalysts were powder coated. The coated composite catalyst bodies were dried at 80 DEG C for 24 hours. The proportions of the composite catalyst body and the monolith were 10 wt% and 90 wt%, respectively.

In order to measure the conversion efficiency of the composite catalyst body by the carbon monoxide oxidation reaction, the measurement conditions were CO 1%, nitrogen 20%, Ar 79%, space velocity 18,000 h ^-1 , carbon monoxide A gas chromatograph (Donam, DS-6200, manufactured by Mitsubishi Heavy Industries, Ltd.) equipped with a thermal conductivity detector was used for the experiment. GC) to determine the concentration of CO.

As a result, as shown in FIG. 1, the CO conversion of manganese-copper-cobalt oxide-coated carbon monolith catalysts showed 100% CO conversion even at a low temperature of 75 ° C. and CO conversion of about 82% even at a low temperature of 50 ° C. Which shows a very high carbon monoxide conversion efficiency at low temperatures.

In the same manner as above, except that the catalyst and the measurement conditions were the same as those described above and additionally the content of water (H ₂ O) was adjusted to 4.2 vol%, the conversion rate of carbon dioxide was continuously maintained .

[Example 2]

The composite catalyst body including the manganese-copper-cobalt-palladium composite oxide catalyst was synthesized by coating a solution of the palladium precursor aqueous solution on the final composite catalyst body of Example 1. First, a palladium precursor aqueous solution in which 0.5 g of palladium (II) nitrate dihydrate, ALDRICH, to 40% Pd basis, Pd nit. Was dissolved in 25.0 g of demineralized water was wash coated on the final composite catalyst of Example 1 To carry a palladium precursor. At this time, the content of the palladium precursor was 0.3 parts by weight based on 100 parts by weight of the composite oxide catalyst. As a result of the experiment under the same conditions as those of Example 1, it was found that carbon monoxide was quantitatively converted even at a very low temperature of 70 ° C, which is not separately shown, to have a very excellent conversion ability. That is, when the Pd precursor was included, it was found that the activity at a lower temperature was better than that of Example 1 which did not include the Pd precursor, and the same activity remained even under the same moisture condition as in Example 1. [

[Comparative Example 1]

Was prepared in the same manner as in Example 1, but without containing copper nitrate and cobalt nitrate precursors. As a result, as shown in Fig. 1, CO conversion was about 82% only when the temperature was raised to about 150 ° C. Further, as a result of the experiment in the same atmosphere in which the water of Example 1 was present, the conversion efficiency of carbon monoxide after 600 minutes was as low as 10% or less

[Comparative Example 2]

The procedure of Example 1 was repeated except that cobalt nitrate was not used. As a result, as shown in FIG. 1, in the case of the manganese-copper oxide coated carbon monolith composite catalyst, CO conversion was 100% at 150 ° C., showing the same efficiency at a relatively high temperature, unlike the embodiments of the present invention Could know. Further, as a result of the experiment in the same atmosphere in which the water of Example 1 was present, the conversion efficiency of carbon monoxide after 600 minutes was as low as 10% or less

Claims (16)

Wherein the carbon monoxide conversion rate is in the range of 50 占 폚 to 100 占 폚 and the carbon monoxide conversion rate is 80% or more including the form in which the composite oxide catalyst prepared from a manganese (Mn) precursor, a copper (Cu) precursor and a cobalt (Composite Catalyst for Oxidation Reaction). The method according to claim 1,
Wherein the mole ratio of the complex oxide catalyst is Mn: Cu: Co = 1: 0.01 to 0.5: 0.01 to 0.5 based on the precursor. The method according to claim 1,
Wherein the support is a carbon monolith. The method according to claim 1,
Wherein the composite catalyst body comprises 1 to 20% by weight of the composite oxide catalyst. The method according to claim 1,
Wherein the binder comprises an inorganic binder or an organic binder. The method according to claim 1,
Wherein the composite catalyst body further comprises a palladium precursor. The method according to claim 6,
Wherein the composite catalyst body has a molar ratio of manganese: palladium = 1: 0.01 to 0.05. delete Manganese, copper (Cu) and cobalt (Co) precursors to form a composite oxide catalyst;
Drying the composite oxide catalyst at 60 ° C to 100 ° C;
Calcining the dried composite oxide catalyst at 200 ° C to 400 ° C;
Coating the calcined composite oxide catalyst on the support surface with a binder to form a composite catalyst body; And
Drying the composite catalyst body at 60 ° C to 100 ° C;
Wherein the carbon catalyst has a carbon monoxide conversion of 80% or more in the range of 50 to 100 占 폚. 10. The method of claim 9,
Washing the composite catalyst body with an aqueous palladium precursor solution;
Wherein the carbon monoxide oxidation reaction is carried out in the presence of a catalyst. 11. The method of claim 10,
Wherein the composite catalyst body has a molar ratio of manganese: palladium = 1: 0.01 to 0.1. 10. The method of claim 9,
Wherein the molar ratio of the complex oxide catalyst is Mn: Cu: Co = 1: 0.01-0.5: 0.01-0.5 based on the precursor. 10. The method of claim 9,
Wherein the support is a carbon monolith. 10. The method of claim 9,
Wherein the composite catalyst body comprises 1 to 20 wt% of the composite oxide catalyst. 10. The method of claim 9,
Wherein the binder comprises an inorganic binder or an organic binder. delete

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