KR101950902B1 - PARATION METOD OF Pd/C CATALYST CAPABLE OF IMPROVING REACTION VITALITY AND Pd/C CATALYST USING THE METHOD - Google Patents

Abstract

The present invention relates to a process for preparing a palladium / carbon catalyst. A first step of preparing a carbon carrier pretreated with a dicarboxylic acid, a second step of dissolving the palladium precursor in an acid solution to prepare a palladium precursor solution, a step of adding a solution of the palladium precursor solution prepared in step 2 A third step of adding a pretreatment agent for increasing the palladium precursor solution to the palladium precursor solution, a fourth step of adding the carbon carrier prepared in the first step to the palladium precursor solution prepared in the third step, A fifth step of stirring, a sixth step of adding a reducing agent to the palladium precursor solution to which the oxidizing agent has been added and stirring, a seventh step of filtering and washing the palladium-supported carbon carrier by the sixth step, and a seventh step of filtering and washing the palladium And a step (8) of heat-treating the supported carbon carrier to produce a palladium / carbon catalyst.

Description

TECHNICAL FIELD [0001] The present invention relates to a palladium / carbon catalyst capable of enhancing hydrogenation reaction activity and a palladium / carbon catalyst prepared thereby, and a palladium /

The present invention relates to a method for producing a palladium / carbon catalyst and a palladium / carbon catalyst prepared thereby, and more particularly, to a method for producing a palladium / carbon catalyst by applying a core- To a process for preparing a palladium / carbon catalyst capable of improving the off-axis hydrogenation activity and a palladium / carbon catalyst prepared thereby.

Palladium / carbon heterogeneous catalysts can be used for various types of reactions, such as reduction of unsaturated hydrocarbons, nitro hydrogenation, benzyl hydrogenation, carbon-carbon bonds and deprotection of cross-linking. Moreover, palladium / carbon catalysts have the advantage of being able to perform simple production processes, high conversion rates, high yield and selectivity, and selective removal of catalyst after reaction completion. As a result, many companies are favored, and they are widely used in petrochemical, fine chemical, and pharmaceutical raw material production processes.

Korean Patent Laid-Open No. 10-2009-0101534 discloses a catalyst suitable for selectively hydrogenating a palladium catalyst, particularly a nitro compound, with hydroxylamine supported on activated carbon, and a process for producing the same, -2002-0025731 discloses a powder hydrogenation catalyst, a process for its preparation, and its use in the catalytic suspension hydrogenation of nitro compounds.

Thus, the palladium / carbon catalyst is prepared by attaching palladium particles, which are metal particles, to the surface of carbon. There are various methods for preparing the palladium / carbon catalyst. Among them, there is a method for enhancing the degree of dispersion of palladium by pretreating the carbon support.

Physical and chemical treatments are used for pretreatment of the carbon carrier, and methods for increasing the dispersibility of palladium have been continuously studied. In the case of the prior art, since the coagulated sintering of the dispersed palladium particles occurs in the heat treatment process, the particle size increases and the dispersibility of the palladium decreases due to the increase of the particle size. There is a problem that is generated.

Korean Patent Publication No. 10-2009-0101534 (2009.09.29) Korean Patent Publication No. 10-2002-0025731 (Apr. 04, 2002)

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a palladium / carbon catalyst having improved activity and excellent activity by applying core-shell coating technology and a method for producing the same and a palladium / do.

Other objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description.

In order to solve the above problems, the present invention provides, as an embodiment, a method for producing a palladium precursor solution, comprising the steps of preparing a carbon carrier pretreated with a dicarboxylic acid, a second step of dissolving the palladium precursor in an acid solution to prepare a palladium precursor solution, A third step of adding a pretreatment agent to raise the pH of the prepared palladium precursor solution, a fourth step of adding the carbon support prepared in the first step to the palladium precursor solution prepared in the third step, A fifth step of adding and stirring an oxidant to the precursor solution, a sixth step of adding and stirring a reducing agent to the palladium precursor solution to which the oxidizing agent has been added, and a sixth step of filtering and washing the palladium- And an eighth step of heat treating the washed and washed palladium-supported carbon support.

Wherein the carbon carrier is activated carbon, and the first step comprises: slurrying and agitating the activated carbon, followed by filtration and washing to prepare an activated carbon cake containing moisture; mixing the water content of the activated carbon cake in an amount of 10-15 wt% And a step of treating the activated carbon cake having the water content corrected by using a dicarboxylic acid so that the dicarboxylic acid is coated on the activated carbon.

Further, in the first step, the dicarboxylic acid is maleic acid, and the maleic acid may be 0.1 to 0.2% by weight based on the weight of the activated carbon.

Meanwhile, in the third step, the pretreatment agent may be an aqueous sodium carbonate solution, and the concentration of the sodium carbonate aqueous solution may be 5 to 20% by weight.

In order to solve the above problem, the present invention proposes a palladium / carbon catalyst prepared by the above method and having a palladium particle size of 2 nm to 5 nm, a dispersion degree of 20% to 30%, and an activity of 97% or more .

According to an embodiment of the present invention, a palladium / carbon catalyst having small particle size, high palladium content and high dispersibility and excellent activity can be produced by dispersing a functional group by dicarboxylic acid and adsorbing palladium by chemical adsorption have.

The effects of the present invention will be clearly understood and understood by those skilled in the art, either through the specific details described below, or during the course of practicing the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart illustrating a process for preparing a palladium / carbon catalyst according to an embodiment of the present invention. FIG.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention.

The singular expressions include plural expressions unless the context clearly dictates otherwise. It is to be understood that the terminology used herein is for the purpose of describing the invention, and is in no way intended to limit the invention to the precise form or scope of the invention, and not to limit the presence or addition of one or more other features, integers, Should not be excluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as being consistent with the meanings in the context of the relevant art and are not to be construed as ideal or overly formal meanings unless explicitly defined in the present application.

Hereinafter, a method for producing a palladium / carbon (Pd / C) catalyst for hydrogenation according to an embodiment of the present invention will be described. However, the present invention is not limited to the following production methods, and the steps of each process may be modified and performed as required.

1 is a flowchart showing a process for producing a palladium / carbon catalyst according to an embodiment of the present invention.

First, a carbon carrier pretreated with a dicarboxylic acid is prepared (S101). The dicarboxylic acid has two carboxyl groups in the molecule.

Next, a palladium precursor solution is prepared by dissolving the palladium precursor in an acid solution (S102), and a pretreatment agent for increasing the pH of the palladium precursor solution is added (S103).

Next, the carbon support is introduced into the palladium precursor solution to which the pretreatment agent has been added (S104), and an oxidant is added to the palladium precursor solution into which the carbon support is introduced (S105).

Next, the reducing agent is added to the palladium-supported carbon carrier and stirred to reduce the supported palladium (S106), followed by filtration and washing (S107), followed by drying and heat treatment to complete the palladium / carbon catalyst (S108) .

Since the palladium particles can be uniformly supported on the surface of the carbon support and the palladium particles can be finely granulated by pre-treating the carbon support with the dicarboxylic acid and introducing the pretreating agent, the oxidizing agent and the reducing agent sequentially into the palladium precursor solution, And a palladium / carbon catalyst having high palladium content and high degree of dispersion and excellent activity can be produced.

Hereinafter, each step will be described step by step with reference to the embodiment of FIG.

(1) A carbon carrier pretreated with a dicarboxylic acid is prepared (hereinafter referred to as the first step).

(1-1) Activated carbon is slurried and stirred, followed by filtration and washing to prepare an activated carbon cake containing moisture, (1-2) correcting the water content, (1-3) ) Dicarboxylic acid to prepare a carbon carrier pretreated with a dicarboxylic acid.

It is possible to slurry the activated carbon by adding an acid solution to the activated carbon and stirring the mixture. The acid solution may be used without limitation to a conventional acid component known in the art. Examples of the acid component include hydrochloric acid, sulfuric acid, nitric acid, acetic acid, or a mixture of at least one of these. Preferably, an aqueous hydrochloric acid solution can be used as the acid solution.

The slurry activated carbon can then be filtered using a filter paper. Cleaning of activated carbon can be carried out using ion exchange water. Thus, it is possible to produce an activated carbon cake containing moisture. The water content of the activated carbon cake is preferably 50 to 60% by weight.

The water content of the thus obtained activated carbon cake is corrected so that the concentration of activated carbon is 10 to 15% by weight. This can be done by adding ion exchange water to the activated carbon cake. Thus, by modifying the moisture content of the activated carbon cake, palladium particles can be supported on the activated carbon with high dispersion.

The dicarboxylic acid is added to the activated carbon cake whose moisture content is corrected and stirred to prepare a pretreated carbon carrier. An example of a dicarboxylic acid is maleic acid. The maleic acid is preferably added in an amount of 0.1 to 0.2% by weight based on the weight of the activated carbon.

When dicarboxylic acid is added to the activated carbon and stirred, one of the carboxy groups on both sides of the dicarboxylic acid bonds to the surface of the activated carbon and the other carboxy group binds to the palladium particles in the loading step. Accordingly, the palladium particles can be uniformly supported on the surface of the activated carbon and the degree of dispersion can be increased.

In addition to maleic acid, dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, Suberic acid, Azelaic acid, Sebacic acid, and the like can be used.

When the palladium particles are supported on the inside of the carbon carrier, the catalytic activity is decreased relative to the amount of palladium used. This is because the palladium particles supported on the surface of the carbon carrier participate in the reaction and the palladium particles supported on the carbon carrier have a low reaction participation rate.

When the dicarboxylic acid is used as in the embodiment of the present invention, palladium particles can be uniformly coated on the surface of the carbon carrier by the action of two carboxy groups to form core-shell particles, and palladium It is possible to remarkably reduce the rate at which the particles are carried.

(2) A palladium precursor solution is prepared by dissolving a palladium precursor in an acid solution (hereinafter referred to as the second step).

In a preferred example of the second step, (1-1) a palladium precursor is metered and dissolved in distilled water, (1-2) an aqueous acid solution is added to the palladium precursor aqueous solution, and the mixture is stirred to prepare a palladium precursor solution.

In the present invention, the acid solution may be used without limitation in a conventional acid component known in the art. Examples of the acid component include hydrochloric acid, sulfuric acid, nitric acid, acetic acid, or a mixture of at least one of these. Preferably, an aqueous hydrochloric acid solution can be used as the acid solution.

In this case, the concentration of the hydrochloric acid aqueous solution does not greatly affect the process in general, but the dissolution time of the palladium precursor, the temperature, the pretreatment agent, and the amount of the oxidizing agent are changed depending on the concentration of the hydrochloric acid aqueous solution.

The above-described palladium precursor is a compound containing palladium (Pd) and capable of dissociation in an acid solution, and conventional palladium precursors known in the art can be used without limitation. For example, palladium chloride (PdCl ₂ ) or the like can be used. The palladium precursor may be used in an amount equivalent to a predetermined amount, and the amount is not particularly limited.

In addition, the palladium precursor solution can be stirred while heating the palladium precursor solution for complete dissolution of the palladium precursor, and the palladium precursor solution can be filtered using a microfilter to remove insolubles.

(3) A pretreatment agent is added to the palladium precursor solution to raise the pH (hereinafter referred to as the third step)

As a preferred example of the third step, the precursor is injected at a constant rate using a metering pump while heating the palladium precursor solution. According to this method, it is easy to control the injection amount and time of the pretreatment agent.

In this embodiment, it is preferable to use an aqueous solution of sodium carbonate (Na ₂ CO ₃ ) as the pretreatment agent. At this time, the concentration of the aqueous solution of sodium carbonate is preferably 5 to 20% by weight. When the concentration of sodium carbonate aqueous solution is less than 5% by weight, the desired pH is reached, and a large amount of sodium carbonate aqueous solution must be supplied. Therefore, when the concentration of sodium carbonate aqueous solution is less than 5% by weight, the palladium particles produced due to the extreme side reaction are not uniform in size It grows.

Sodium carbonate is a weak oxidizing agent with a weaker activity than sodium hydroxide so that the pH is gradually increased so that palladium particles having a small and uniform particle size distribution of 4 nm or less are produced. If sodium hydroxide is used directly, it is difficult to produce a uniform particle size distribution and palladium particles of 4 nm or less.

Thus, the pH of the solution of the palladium precursor is increased and at least one kind of palladium (Pd ⁰ , Pd ^{2 +} ) is formed through the injection of the sodium carbonate aqueous solution as the pretreatment agent. As the pH increases, the amount of Pd ^{2 +} (PdO) increases. The pH is preferably in the range of 3 to 5.

(4) The carbon carrier is added to the palladium precursor solution to which the pretreatment agent is added (hereinafter referred to as the fourth step)

In this embodiment, the carbon carrier uses a carbon carrier pretreated with dicarboxylic acid according to the first step described above.

The average particle diameter, specific surface area and form of the carbon carrier are not particularly limited and can be appropriately adjusted within the ordinary range known in the art.

At this time, the carbon carrier may be introduced alone into the palladium precursor solution or mixed with the carbon carrier and water. When the water content of the carbon carrier itself is large, the water may be added without mixing with water. In the case where the water content of the carbon carrier itself is large, water may be mixed and introduced.

(5) The palladium is supported on the carbon carrier (hereinafter referred to as the fifth step).

In a preferred example of the fifth step, (5-1) an oxidant is added to a palladium precursor solution to which a carbon support is added, stirring is performed at a temperature range of (5-2), and the pH of the palladium precursor solution is adjusted to 5 to 11 Lt; RTI ID = 0.0 >% < / RTI > to the palladium on the carbon support.

At this time, the temperature is not particularly limited as long as palladium can be supported on the carbon support, but it is preferable to maintain the temperature at 70 to 90 ° C. When the amount is less than 70, the palladium is carried on the carbon carrier at a slow time or in a poor manner, and when it exceeds 90, the palladium dispersion becomes poor.

In this embodiment, the oxidizing agent may be a conventional component known in the art. For example, it is preferable to use an aqueous solution of sodium hydroxide (NaOH). At this time, the concentration of the aqueous sodium hydroxide solution does not greatly affect the process of the present invention, but the amount and time of the injection should be appropriately changed according to the concentration of the aqueous sodium hydroxide solution.

Specifically, 10 to 40% by weight aqueous solution of sodium hydroxide is injected at a constant rate using a metering pump, and after reaching a specific pH, an aqueous solution of sodium hydroxide is continuously injected so that the pH can be maintained. According to this method, it is easy to control the injection amount and time of the sodium hydroxide aqueous solution.

In this way, the pH of the palladium precursor solution is changed by injecting an aqueous solution of sodium hydroxide, which is an oxidizing agent. At this time, the pH of the palladium precursor solution is preferably kept constant in the range of 5 to 11, and the holding time is preferably 15 to 120 minutes.

In this process, Pd ^{2 +} dissolved in the liquid phase reacts with sodium hydroxide to form Pd (OH) ₂ particles, which are carried on the carbon carrier. Since the dicarboxylic acid is coated on the carbon carrier, the palladium particles are supported on the carbon carrier at a high dispersion of 20 to 30%.

(6) The palladium supported on the palladium-supported carbon carrier is reduced (hereinafter referred to as the sixth step)

As a preferable example of the sixth step, for example, (6-1) a reducing agent is added to the solution prepared in the fifth step in which the palladium-supported carbon carrier is contained, (6-2) the solution in which the reducing agent is introduced The palladium is reduced by stirring for a certain time at a constant temperature range.

By this process, the palladium particles supported on the carbon carrier in the form of Pd (OH) ₂ are reduced to produce palladium metal particles. At this time, various kinds of reducing agents can be used, but it is preferable to use hydrazine (N ₂ H ₄ ), sodium borohydride (NaBH ₄ ), formaldehyde (HCHO) or the like having excellent reducing power.

(7) The palladium-loaded carbon support is filtered and washed (hereinafter referred to as step 7).

After the reduction process is completed, the solution prepared in the sixth step containing the palladium-supported carbon support is filtered and washed. In this case, washing is preferably 3 to 4 times.

In the seventh step, the palladium / carbon catalyst may be filtered and washed by any conventional method known in the art without limitation.

(8) The palladium-supported carbon support after filtration and washing is dried and heat-treated (hereinafter referred to as the eighth step)

The washed palladium-loaded carbon support is dried in the oven at a constant temperature for a certain period of time and then heat-treated at a constant temperature for a certain period of time using hydrogen (H ₂ ) gas. This process removes moisture and removes the organic material coated on the carbon carrier. In the case of maleic acid, removal is possible below 300.

As described above, according to the embodiment of the present invention, palladium / carbon catalyst having small particle size, high palladium content and high degree of dispersion, and excellent activity can be obtained by dispersing the functional group by dicarboxylic acid and adsorbing palladium by chemical adsorption Can be produced.

The palladium / carbon catalyst prepared in the present invention may be usefully used as a catalyst for a hydrogenation reaction known in the art, and may be usefully applied to various fields where a palladium catalyst is required.

Next, an embodiment of a method for producing a palladium / carbon catalyst according to an embodiment of the present invention will be described in detail. The following examples and comparative examples are merely illustrative of one embodiment of the present invention, and the scope of the present invention is not limited by the following examples and comparative examples.

[ Example  One]

<Preparation of Carrier>

1) Activated carbon was slurried in 3% hydrochloric acid at 20% by weight, stirred at 50 ° C for 30 minutes, and then filtered and washed. The water content of the filtered activated carbon cake was 50 to 60% by weight.

2) The water content of the filtered activated carbon was corrected, and ion-exchanged water was added so that the concentration of activated carbon was 10% by weight.

3) 45 g of 10 wt% active carbon prepared as above was weighed and obtained.

4) 0.045 g of maleic acid corresponding to 0.1% by weight was added to the obtained activated carbon and stirred at 80 캜 to prepare a carrier solution.

&Lt; Preparation of palladium (Pd) particles >

5) 8.4 g of PdCl ₂ (59.5% of Pd) was weighed and dissolved in 1000 ml of distilled water, followed by addition of 5 ml of 35% HCl and stirring.

6) The PdCl ₂ solution was heated to 60 ° C and dissolved for 30 minutes, and insolubles were removed using a microfilter.

7) The filtrate having passed through the microfilter was heated to 50 ° C and stirred, and 10% Na ₂ CO ₃ solution was slowly added dropwise to maintain pH 4.0.

8) The solution 7) was added to the solution 4), stirred at 80 ° C, 10% sodium hydroxide solution was added dropwise using a metering pump, pH was adjusted to 7.0 ± 0.3, Respectively.

9) 50 g of hydrazine diluted to 50% was added uniformly for 30 minutes, and the mixture was stirred at 80 ° C for 60 minutes.

10) The solution of the above 9) in which palladium particles were supported on activated carbon was subjected to filter press and washed with ion exchange water.

11) The filtrate obtained in 10) was dried in an oven at 100 ° C for 10 hours and then heat-treated at 500 ° C for 1 hour using 5% H ₂ to obtain a palladium / carbon catalyst.

[ Comparative Example  One]

1) A 5 wt% hydrochloric acid aqueous solution was prepared.

2) 10% by weight (relative to the carrier) of palladium precursor (PdCl ₂ , 5.55 g) was added to the solution of the above 1), and the solution was completely dissolved by heating to 60 ° C. When the dissolution was completed, the temperature of the solution was lowered to room temperature.

3) A 10 wt% aqueous solution of sodium hydroxide (NaOH) was injected into the solution of the above 2) by using a metering pump. At this time, 50 g of aqueous sodium hydroxide solution was added.

4) After the aqueous solution of sodium hydroxide was injected, the pH of the palladium precursor solution was kept constant at 5.5 ± 1 and stirred for 30 minutes.

5) Carbon carrier and water were mixed and injected into the 4) palladium precursor solution at a weight ratio of 1:10.

6) The temperature of the final solution was raised to 72.5 占 폚 and stirred for 30 minutes.

7) To the solution of 6), 27 g of a 35% by weight aqueous solution of formaldehyde (HCOH) was added.

8) The solution 7) was filtered and washed to obtain a palladium / carbon catalyst.

This comparative example is an example when one of the existing methods is used. Since there is no process of pretreating the carbon carrier with dicarboxylic acid, the dispersion and activity (reactivity) are low and palladium precursor solution is not pre-treated with sodium carbonate.

[ Comparative Example  2]

1) A 5 wt% hydrochloric acid aqueous solution was prepared.

2) 10% by weight (relative to the carrier) of palladium precursor (PdCl _{2 ,} 5.55 g) was added to the solution of the above 1), and the solution was completely dissolved by heating to 60 ° C. When the dissolution was completed, the temperature of the solution was lowered to room temperature.

3) An aqueous 10 wt% sodium carbonate (Na ₂ CO ₃ ) solution was injected into the activated carbon. At this time, 60.3 g of an aqueous sodium carbonate solution was added.

4) Palladium precursor solution No. 2) was poured into the solution of the above 3), stirred and then heated to 80 ° C.

5) To the solution of 4) above, a 10 wt% aqueous solution of sodium hydroxide (NaOH) was added. The amount of the aqueous solution of sodium hydroxide is preferably 11.1 g.

6) The solution of 5) was injected at 20 ml / min for 2 hours using hydrogen gas.

7) Solution 6) was filtered and washed.

This comparative example is generally a process similar to the embodiment or an example in which the carbon carrier is not pretreated with dicarboxylic acid. It was confirmed that the prepared palladium / carbon catalyst had low dispersibility and activity.

The following comparative experiments were performed on the palladium / carbon catalyst prepared according to the present invention and the palladium / carbon catalyst prepared according to Comparative Examples 1 to 2 as described above.

[ Experimental Example  1] Quantification of the water content of the palladium / carbon catalyst

The moisture content of each catalyst was quantified for evaluation of the palladium / carbon catalyst prepared according to Example 1 and Comparative Examples 1-2. The dehydration process was completed by pressure filtration and the water content of the palladium / carbon catalyst was analyzed and used in the experiment to obtain the same amount of palladium. The water content of each palladium catalyst was 52 ± 0.5 wt%. This is shown in Table 1.

Item Example Comparative Example 1 Comparative Example 2 Water content (% by weight) 52.3 51.8 52.1

[ Experimental Example  2] Characterization of palladium / carbon catalysts

The palladium (Pd) content, the particle size, the degree of dispersion, and the reactivity of the catalyst were evaluated for the three catalysts of Example 1 and Comparative Examples 1 and 2 as follows.

At this time, the reaction evaluation result was measured by using O-debenzylation reaction of dibenzylether as a reaction model, and conversion rate was recorded after 20 minutes of reaction time. The results are shown in Table 2.

Dimension Example 1 Comparative Example 1 Comparative Example 2 Pd content (% by weight) 9.98 9.21 9.57 Particle Size (nm) 3.1 18.5 8.7 Metal Dispersibility (%) 25.8 11.2 15.4 Reactivity results (%) 99.2 88.4 92.3

As a result of the experiment, the catalysts of the examples exhibited higher palladium (Pd) content, uniform metal dispersion, and higher reaction activity than those of Comparative Examples 1 and 2.

Further, in the case of the examples, it was observed that the palladium particles of 5 nm or less were evenly distributed on the surface of the carrier, but in the case of Comparative Examples 1 to 2, agglomeration phenomenon of palladium particles was observed.

It is apparent that the specific description of the present invention described above is susceptible to various implementations by those skilled in the art.

It will be appreciated that those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

While the present invention has been described in connection with what is presently considered to be practical and exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (5)

A first step of preparing a carbon carrier pretreated with a dicarboxylic acid,
A second step of dissolving the palladium precursor in an acid solution to prepare a palladium precursor solution,
A third step of adding a pretreatment agent for increasing the pH to the palladium precursor solution prepared in the second step,
A fourth step of injecting the carbon carrier prepared in the first step into the palladium precursor solution prepared in the third step,
A fifth step of adding an oxidant to the palladium precursor solution into which the carbon support is introduced and stirring the mixture,
A sixth step of adding a reducing agent to the palladium precursor solution to which the oxidizing agent has been added and stirring the mixture,
A seventh step of filtering and washing the palladium-supported carbon carrier by the sixth step, and
Step 8 for heat-treating the filtered and washed palladium-loaded carbon support
Lt; / RTI &gt;
The carbon carrier is activated carbon,
In the first step,
Slurrying and stirring the activated carbon, filtering and washing the activated carbon to prepare an activated carbon cake containing moisture,
Correcting the water content of the activated carbon cake to be 10 to 15% by weight, and
Treating the activated carbon cake in which the moisture content is corrected with dicarboxylic acid to coat the activated carbon with the dicarboxylic acid
&Lt; / RTI &gt; delete The method according to claim 1,
In the first step,
Wherein the dicarboxylic acid is maleic acid and the maleic acid is 0.1 to 0.2% by weight, based on the weight of activated carbon
Palladium / carbon catalyst. The method according to claim 1,
In the third step,
Wherein the pretreatment agent is an aqueous solution of sodium carbonate,
And the concentration of the sodium carbonate aqueous solution is 5 to 20% by weight
Palladium / carbon catalyst. delete

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