KR101462690B1 - Pd/C hydrogenation catalyst, preparation and use thereof - Google Patents

Abstract

The present invention provides a palladium / carbon hydrogenation catalyst containing carbon particles activated as a support material and containing metal palladium as an active component, wherein the content of the metal palladium is in the range of from 0.1 to 5 By weight, preferably 0.2 to 3.5% by weight, more preferably 0.3 to 0.8% by weight, and at least 45% by weight of said palladium is contained in an outer layer at a depth of 0.2 to 20 탆 of said support material, Wherein less than 10% by weight of the palladium is contained in an outermost layer at a depth of less than 0.2 microns of the support material and the remaining weight percent of the palladium is in the range of 20 to 400 microns . The present invention also relates to a process for preparing the palladium / carbon catalyst and to the use of the palladium / carbon catalyst.

Palladium / carbon, hydrogenation, catalyst

Description

Pd / C hydrogenation catalyst, preparation and use thereof "

The present invention relates to a process for producing palladium / carbon hydride catalysts and palladium / carbon hydride catalysts and their use.

The palladium / carbon catalyst is a selective hydrogenation catalyst that can be used to selectively hydrogenate aldehydes, especially aromatic aldehydes. Specifically, palladium / carbon catalyst is an aromatic aldehyde having a composition formula of X- aromatic ring -CHO to X- aromatic ring -CH ₂ OH, X- or more aromatic rings in the aromatic ring X- -CHO to -CH ₃ optionally Where X is methyl or carboxyl and the aromatic ring is a benzene ring or a naphthalene ring and the aromatic aldehyde is hydrogenated in an acidic solution or aqueous solution at a temperature of 100 to 300 DEG C in the presence of hydrogen.

Based on the foregoing, the palladium / carbon catalyst can be prepared by hydrogenation of low purity terephthalic acid and low purity 2,6-naphthalene dicarboxylic acid as well as low purity 4- (hydrocarbons such as aromatic aldehydes) (Hydroxymethyl) benzoic acid by selective hydrogenation of impurities in the benzylic acid. Specifically, 4-carboxybenzaldehyde (hereinafter, simply referred to as '4-CBA') in low purity terephthalic acid is hydrogenated to methylbenzoic acid through two-stage hydrogenation, and 4-CBA in low purity 4- (hydroxymethyl) 2-formyl-6-naphthoic acid in low purity 2,6-naphthalenedicarboxylic acid, which is hydrogenated with 4- (hydroxymethyl) benzoic acid through a one- Is hydrogenated with 2-methyl-6-naphthoic acid.

However, since palladium is used as the sole active component for the palladium / carbon catalyst, the distribution of metal palladium on the support material has a significant effect on the hydrogenation characteristics of the catalyst.

Furthermore, because the selective hydrogenation of aromatic aldehydes is a primary reaction at high speed, it is not easy for the reactants to diffuse into the interior of the catalyst during the reaction, so that the active metals in the particles can not function sufficiently. Therefore, the active metal palladium should be contained in the outside of the catalyst particles as much as possible. In addition, the greater the surface area at which the palladium contacts the reactants, the better the activity of the catalyst.

Thus, in connection with palladium / carbon catalysts, U.S. Patent No. 4,476,242 proposes to contain all active metal palladium in the surface layer at a depth of less than 70 to 80 탆 of the particles; U.S. Patent No. 6,066,589 discloses that less than 50 weight percent of the metal palladium in the outer layer at a depth less than 50 microns of the support material and the remaining weight percent of the metal palladium in the inner layer at a depth of 50 to 400 microns of the support material, , And the like; Canadian Publication No. 1,457,922A has prepared catalysts, which show high conversions of 4-CBA during, for example, hydrogenation of low purity terephthalic acid, but up to 30% by weight of palladium Is contained in an outermost layer at a depth of less than 0.2 탆 of the support material, resulting in a large loss of palladium in the surface layer of the support material due to direct wear.

On the basis of prior art palladium / carbon catalysts, under the condition that there is no impairment of catalytic activity, the present invention is based on the finding that palladium contained in the outermost layer of the support material, such as palladium To reduce the loss of palladium due to wear during use.

Specifically, the present invention provides a palladium / carbon hydride catalyst containing carbon particles activated as a support material and containing metal palladium as an active component, wherein the content of the metal palladium is based on the total weight of the catalyst 0.1 to 5% by weight, preferably 0.2 to 3.5% by weight, more preferably 0.3 to 0.8% by weight, and at least 45% by weight of the palladium is present in the outer layer at a depth of 0.2 to 20 [ Wherein less than 10 weight percent of the palladium is contained in an outermost layer at a depth less than 0.2 microns of the support material and the remaining weight percent of the palladium is at a depth of 20 to 400 microns of the support material Lt; / RTI >

According to the palladium / carbon catalyst of the present invention, the activated carbon particles have a specific surface area of 600 to 1800 m ² / g, preferably 800 to 1500 m ² / g, and a pore volume of 0.30 to 0.85 ml / natural or shaped particles, preferably natural or some form of coconut charcoal particles having a pore volume of at least 90% by weight of the particles, Has a size of 4 to 8 mesh.

According to the palladium / carbon catalyst of the present invention, preferably 45 to 60% by weight of said palladium is contained in an outer layer at a depth of 0.2 to 20 탆 of said support material; Preferably, the remaining weight percent of the palladium is contained within the inner layer at a depth of 20 to 180 탆 of the support material.

The invention includes the following steps

(a) selecting activated carbon particles suitable as support material particles;

(b) contacting the activated carbon particles with a competing adsorbate at 0 to 50 DEG C, preferably at room temperature for 5 to 60 minutes, preferably 10 to 30 minutes, to obtain pre-impregnated activated carbon particles; Wherein the competitive adsorbent material is an aqueous solution of a lower organic acid having a carbon number of 1 to 6 at a concentration of 0.01 to 0.5N (normal), preferably 0.05 to 0.2N, impregnating, filtering and drying the mixture;

(c) a weakly acidic solution containing a palladium precursor and a surfactant by impregnation or spray coating to obtain a supported catalyst, wherein the slightly acidic solution comprises 3 to 6 wherein the palladium is present in an amount of from 0.1 to 5% by weight, preferably from 0.2 to 3.5% by weight, more preferably from 0.3 to 0.3% by weight, based on the total weight of the catalyst, of palladium on the pre- ≪ / RTI > to about 0.8% by weight;

(d) aging the supported catalyst in air for 1 to 24 hours to obtain an aged catalyst; And

(e) reducing the aged catalyst to a reducing agent at a temperature of 0 to 200 DEG C, preferably 50 to 120 DEG C for 0.5 to 10 hours, preferably 1 to 4 hours to obtain an activated catalyst

Lt; / RTI >

The next step

(b ') removing dirt and loose portions from the surface of the particles before said step (b), washing said particles with inorganic acid, deionized water until neutral Washing the particles, and drying the pre-treating step

RTI ID = 0.0 >

Palladium / carbon catalyst. ≪ / RTI >

According to the process for preparing the palladium / carbon catalyst of the present invention,

In the step (a), the selected activated carbon particles have a specific surface area of 600 to 1800 m ² / g, preferably 800 to 1500 m ² / g and a specific surface area of 0.30 to 0.85 ml / g, preferably 0.40 to 0.60 ml / g Preferably naturally occurring or some form of coconut charcoal particles having a pore volume of at least 90% by weight of the particles, and at least 90% mesh size;

In step (b '), the inorganic acid used in the washing step has a concentration of 0.1 to 0.5N and is selected from the group consisting of hydrochloric acid, nitric acid, phosphoric acid, and mixtures thereof. washing is intended to condition functional groups on the surface of the activated carbon particles and the drying step is carried out at a temperature of from 100 to 200 ° C, preferably from 110 to 150 ° C;

In the step (b), the low molecular weight organic acid is selected from the group consisting of citric acid, maleic acid, oxalic acid, lactic acid, and a mixture thereof, preferably citric acid, and the temperature of the drying step is 100 to 200 ° C, Preferably 110 to 150 < 0 >C;

In step (c), the palladium precursor may be at least one selected from the group consisting of palladium chloride, palladium oxide, palladium acetate, palladium nitrate, palladic chloride, Alkaline salts of palladic chloride, complexes of palladium with an amine, and mixtures thereof, preferably palladic chloride; The surfactant has a concentration of from 0.2 to 5% by weight, preferably from 0.5 to 1.5% by weight; The surfactant is used to modify the distribution and / or dispersion characteristics of the palladium, and the surfactant is a cationic surfactant, preferably an aliphatic ether sulphate alkali metal salt and a poly Oxyethylene aliphatic ether phosphate alkali metal salt, and specific examples thereof include sodium polyoxyethylene dodecyl ether sulfate, potassium polyoxyethylene dodecyl ether sulfate, sodium polyoxyethylene dodecyl ether phosphate, and potassium polyoxyethylene dodecyl ether phosphate ; The pH of the solution is adjusted by the addition of a carbonate, a hydro- carbonate or a hydroxide of an alkali metal. Specific examples of the alkali metal compound include sodium carbonate, potassium carbonate, sodium hydro- carbonate, potassium hydro- carbonate, sodium hydro- oxide, Oxides and the like; The step of supporting the palladium on the pre-impregnated activated carbon particles is carried out at a temperature of 0 to 50 DEG C for 0.5 to 6 minutes, preferably 1 to 3 minutes, preferably at room temperature, , Spraying said solution onto said pre-impregnated activated carbon particles at a rate of 5 to 20 ml / min (min), preferably at room temperature;

In the step (e), the reducing agent is selected from the group consisting of formic acid, sodium formate, formic aldehyde, hydrazine hydrate, glucose, hydrogen, and mixtures thereof, preferably sodium formate.

  According to the process for preparing the palladium / carbon catalyst of the present invention, the support material, i.e. the activated carbon particles, is pre-impregnated with a competitive adsorbent material, and some adsorption sites on the support material are filled, Or less is contained within the outermost layer at a depth of less than 0.2 [mu] m of the support material, thereby reducing the loss of palladium due to wear. Thus, the palladium / carbon catalyst of the present invention has advantages such as excellent stability and long service life.

As described above, the present invention also relates to the use of said palladium / carbon catalyst for the purification of low purity terephthalic acid and low purity 2,6-naphthalene dicarboxylic acid as well as of low purity 4- (hydroxymethyl) benzoic acid In which the process is carried out in the presence of the palladium / carbon catalyst at a temperature of 100 to 300 DEG C to convert the impurities of the aromatic aldehydes contained therein to obtain hydrogenated refined or refined products, ) Is contacted with hydrogen.

All of the catalysts prepared according to the present invention considerably reduce the amount of palladium contained in the outermost layer (0.2 탆 or less), and these amounts are controlled to less than 10 wt% so that even after 1000 hours of operation, .

In addition, palladium is mainly contained in the outer layer (0.2-20 [mu] m) so that the initial activity of these catalysts can be ensured (i.e. a high conversion of 4-CBA can be obtained in the batch reaction) A very low reduction in activity was found, still being maintained after running for hours.

In addition, the catalyst according to the invention reduces the loss of palladium during operation through additional optimization of the palladium distribution, thus increasing the catalyst stability and extending the lifetime of the catalyst without impairing the activity of the catalyst.

The invention will now be described in further detail by means of the following non-limiting embodiments.

Preparation of Catalyst

Example  One

Weighing 50 g (gram) of coconut char particles in a flake state having a particle size of 4 to 8 mesh, a specific surface area of 1078 m ² / g and a pore volume of 0.47 ml / g; Removing loose and loose portions from the surface of the particles, washing the particles with nitric acid at a concentration of 0.5N in a vessel for one hour at 80 DEG C, Washing the particles with deionized water, and finally drying the particles at 120 ° C for two hours; Pre-impregnating the coconut char particles with an aqueous solution of citric acid at a concentration of 0.1N for 15 minutes at room temperature, followed by filtering, and drying at 120 ° C for two hours; Adding 1.25 g of an aqueous solution of paladic chloride containing 20% by weight of palladium, adding 15 g of deionized water to the aqueous solution to form an impregnation solution, adding 0.45 g of potassium polyoxyethylene dodecane Adjusting the solution to pH 5.5 by adding the required amount of sodium carbonate, and finally adding 5 g of a solution of the coconut charcoal particles so that the solution has a volume such that the coconut charcoal particles can only be immersed Replenishing deionized water, and then impregnating the coconut char particles with the solution for about one minute to obtain the palladium / carbon catalyst; Aging the palladium / carbon catalyst in air for 24 hours, then reducing the palladium / carbon catalyst to an aqueous solution of sodium formate for 4 hours at 80 < 0 > C, Washing the palladium / carbon catalyst, and finally drying the palladium / carbon catalyst to obtain Catalyst A.

Example  2

To obtain Catalyst B, Example 1 is repeated except that the competitive adsorbent material is lactic acid and 2.00 g of an aqueous solution of palladic chloride containing 20% by weight of palladium is injected.

Example  3

Impregnating the coconut char particles with an aqueous solution of citric acid at a concentration of 0.2N for 20 minutes without washing the coconut charcoal particles with nitric acid to obtain Catalyst C, and pre-impregnating the coconut char particles with palladium chloride containing 20% by weight of palladium Lt; RTI ID = 0.0 > 1 < / RTI >

Example  4

To obtain Catalyst D, Example 1 is repeated except for the step of injecting 6.25 g of an aqueous solution of palladic chloride containing 20% by weight of palladium.

Example  5

To obtain Catalyst E, Example 1 is repeated, except that 0.50 g of an aqueous solution of palladium nitrate containing 20% by weight of palladium is injected.

Example  6

To obtain the catalyst F, pre-impregnating the coconut char particles with an aqueous solution of lactic acid at a concentration of 0.4 N for 5 minutes, and the step of injecting 3.50 g of an aqueous solution of palladium nitrate containing 20% by weight of palladium Example 1 is repeated.

Example  7

To obtain the catalyst G, pre-impregnating the coconut char particles with an aqueous solution of lactic acid at a concentration of 0.04 N for 30 minutes, and the step of injecting 8.75 g of an aqueous solution of palladic chloride containing 20% by weight of palladium And Example 1 is repeated

Example  8

Injecting 11.25 g of an aqueous solution of paladic chloride containing 20% by weight of palladium, and a rate of 10 ml / min (min) to obtain catalyst H, wherein the competitive adsorbent material is an aqueous solution of a mixture of citric acid and lactic acid, Example 1 is repeated except that palladium is supported on the coconut charcoal particles by spray coating.

compare Example  One

To obtain Catalyst I, Example 1 is repeated except that the coconut char particles are not pre-impregnated.

compare Example  2

To obtain Catalyst J, Example 1 is repeated except that no potassium polyoxyethylene dodecyl ether phosphate is added to the aqueous solution of palladic chloride.

compare Example  3

To obtain catalyst K, Example 1 is repeated except that the coconut char particles are not pre-impregnated and potassium polyoxyethylene dodecyl ether phosphate is not added to the aqueous solution of palladic chloride.

In the present specification, the weight percent of palladium supported on the palladium / carbon catalyst prepared in all of the above Examples and Comparative Examples is determined by the inductively coupled plasma spectrophotometer (ICP-AES) and the distribution of the supported palladium Is determined as follows: The amount of palladium contained at a depth of 20 탆 or less and the amount of palladium contained at a depth of 180 탆 or less is determined by an electronic microprobe analysis (EMPA) The ratio of palladium atoms is determined by X-ray photoelectron spectroscopy (XPS).

Further, all of the palladium / carbon catalysts prepared in all of the above Examples and Comparative Examples are tested through hydrogenation purification of low purity terephthalic acid. The samples are analyzed by HPLC.

For the initial activity, i.e. final conversion of 4-CBA, each catalyst is checked by batch reactions in a high pressure autoclave under the following conditions: the amount of each catalyst is 2.0 g; The amount of terephthalic acid was 30.0 g; The amount of 4-CBA is 1.0 g; The reaction pressure is 8.0 MPa (gauge); The reaction temperature is 280 ° C.

For operational activity and final palladium loss, each catalyst is examined by a continuous reaction in a continuous apparatus under the following conditions: the amount of each catalyst is 200.0 g; The speed of the slurry is 3 Kg / h; The content of terephthalic acid is 5% by weight; The content of 4-CBA is 0.35% by weight; The reaction pressure is 8.0 MPa (gauge); The reaction temperature is 280 占 폚; The reaction time is 1000 hours, except that the reaction time of the catalyst A is 6000 hours.

During the test, the conversion of 4-CBA is calculated as follows.

Conversion: (initial amount of 4-CBA-amount of 4-CBA after reaction) x 100% ÷ initial amount of 4-CBA

The evaluation of the supported palladium, palladium distribution and initial activity of each of the palladium prepared in all the above Examples and Comparative Examples is shown in Table 1.

catalyst Supported
Pd (% by weight) Pd distribution (% by weight) Conversion of 4-CBA (%) 0-0.2mm 0.2-20 mm 20-180mm 180-400mm A 0.50 9.1 60.5 30.4 0 99.0 B 0.80 9.4 62.3 28.3 0 99.2 C 1.00 8.3 53.1 38.6 0 99.3 D 2.49 9.2 60.3 30.5 0 99.5 E 0.20 9.1 61.5 29.4 0 85.7 F 1.40 8.2 51.0 40.8 0 99.4 G 3.49 9.5 70.6 19.9 0 99.6 H 4.48 8.8 62.8 28.4 0 99.7 I 0.50 16.3 59.9 23.8 0 99.8 J 0.50 8.5 40.5 36.3 14.7 94.3 K 0.49 14.3 37.2 34.9 13.6 99.2

The evaluation of the loss and operational activity of the supported palladium, palladium of each catalyst prepared in all the examples and comparative examples after 1000 hours of operation in a continuous apparatus is shown in Table 2.

catalyst Supported Pd wt%
(After 1000 hours of operation) Loss of Pd (% by weight) Conversion of 4-CBA (%) Decrease in conversion (%) A 0.48 0.02 97.9 1.1 B 0.76 0.04 98.0 1.2 C 0.96 0.04 98.3 1.1 D 2.43 0.06 98.5 1.0 E 0.18 0.02 84.5 1.2 F 1.36 0.04 98.1 1.3 G 3.44 0.05 98.2 1.4 H 4.40 0.08 98.3 1.4 I 0.40 0.10 95.5 4.3 J 0.49 0.01 93.2 1.1 K 0.42 0.07 97.2 2.0

The evaluation of the supported palladium, palladium loss and activity activity of the catalyst A prepared in Example 1 after running in a continuous apparatus for 6000 hours is shown in Table 3. < tb > < TABLE >

catalyst Supported Pd wt%
(After 6000 hours of operation) Loss of Pd (% by weight) Conversion of 4-CBA (%) Decrease in conversion (%) A 0.43 0.07 97.6 1.4

As can be seen from the data in the above Tables 1 and 2, all the catalysts prepared according to the present invention considerably reduce the amount of palladium contained in the outermost layer (0.2 탆 or less), that is, , So that all the catalysts have only a sparse, low loss of palladium even after 1000 hours of operation; Furthermore, palladium is mainly contained in the outer layer (0.2 to 20 μm) so that the initial activity of these catalysts can be ensured, ie a high conversion of 4-CBA can be obtained in the batch reaction, Lt; RTI ID = 0.0 > activity, i. E., Very low < / RTI >

In addition, as can be seen from the data in Table 3, even after 6000 hours of operation, catalyst A still has 0.43 wt.% Of supported palladium, the loss of palladium is only 0.07%, and the conversion of 4-CBA is Still 97.6%, for example, the loss of conversion is only 1.4%

Thus, the catalyst according to the invention reduces the loss of palladium during operation through additional optimization of the palladium distribution, thus increasing the catalyst stability and extending the lifetime of the catalyst without impairing the activity of the catalyst.

Various modifications may be made by those skilled in the art without departing from the spirit and scope of the invention as defined by the following claims. It is not. Accordingly, the scope of the present invention should not be limited by the above-described exemplary embodiments, but should be determined only in accordance with the following claims and their equivalents.

Claims (17)

In the palladium / carbon hydrogenation catalyst, Containing activated carbon particles as a support material and containing metal palladium as an active ingredient, The content of the metal palladium is 0.1 to 5 wt% based on the total weight of the catalyst, Wherein at least 45% by weight of the palladium is contained in an outer layer at a depth of 0.2-20 [mu] m of the support material and less than 10% by weight of the palladium is in an outermost layer ), The remaining weight percent of said palladium being contained in an inner layer at a depth of 20 to 400 탆 of said support material Palladium / Carbon Hydrogenation Catalyst. The method according to claim 1, Wherein the activated carbon particles are natural or shaped coconut charcoal particles. 3. The method according to claim 1 or 2, The activated carbon particles have a specific surface area of 600 to 1800 m ² / g and a pore volume of 0.30 to 0.85 ml / g, More than 90% by weight of the activated carbon particles have a size of 4 to 8 mesh Palladium / Carbon Hydrogenation Catalyst. 3. The method according to claim 1 or 2, Wherein the content of the metallic palladium is 0.2 to 3.5 wt% based on the total weight of the catalyst. 3. The method according to claim 1 or 2, 45 to 60% by weight of said palladium is contained in an outer layer at a depth of 0.2 to 20 탆 of said support material. 3. The method according to claim 1 or 2, Wherein the remaining weight percent of the palladium is contained within the inner layer at a depth of 20 to 180 탆 of the support material. A process for preparing a palladium / carbon hydride catalyst containing carbon particles activated as a support material and containing metal palladium as an active component, (a) selecting said activated activated carbon particles as particles of said support material; (b) contacting the activated carbon particles with a competing adsorbate at 0 to 50 DEG C for 5 to 60 minutes to obtain pre-impregnated activated carbon particles, wherein the competing adsorbent material is 0.01 to 0.5N (normal) Pre-impregnating, filtering and drying an aqueous solution of a lower organic acid having a carbon number of 1 to 6 at a concentration of 1 to 6 carbon atoms; (c) a weakly acidic solution containing a palladium precursor and a surfactant by impregnation or spray coating to obtain a supported catalyst, wherein the slightly acidic solution has a pH of from 3 to 6 - supporting the palladium on the pre-impregnated activated carbon particles, wherein the palladium is supported in an amount of from 0.1 to 5% by weight based on the total weight of the catalyst; (d) aging the supported catalyst in air for 1 to 24 hours to obtain an aged catalyst; And (e) reducing the aged catalyst to a reducing agent at a temperature between 0 and 200 < 0 > C for 0.5 to 10 hours to obtain an activated catalyst ≪ / RTI > 8. The method of claim 7, The process for producing the palladium / carbon hydride catalyst (b ') removing dirt and loose portions from the surface of the particles before said step (b), washing said particles with inorganic acid, deionized water until neutral Washing the particles, and drying the pre-treating step Further comprising Palladium / carbon catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In the step (a), the selected activated carbon particles are naturally or some form of coconut charcoal particles having a specific surface area of 600 to 1800 m ² / g and a pore volume of 0.30 to 0.85 ml / g , At least 90% by weight of the particles have a size of 4 to 8 mesh Palladium / carbon catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In step (b), the low molecular weight organic acid is selected from the group consisting of citric acid, maleic acid, oxalic acid, lactic acid, and mixtures thereof, The temperature of the drying step is in the range of 100 to 200 DEG C Palladium / carbon hydride catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In step (c), the palladium precursor may be at least one selected from the group consisting of palladium chloride, palladium oxide, palladium acetate, palladium nitrate, palladic chloride, Alkaline salts of palladic chloride, complexes of palladium with an amine, and mixtures thereof. Palladium / carbon hydride catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In the step (c) The surfactant has a concentration of 0.2 to 5% by weight, Wherein the surfactant is a cationic surfactant selected from the group consisting of polyoxyethylene aliphatic ether sulfate alkali metal salts and polyoxyethylene aliphatic ether phosphate alkali metal salts, The pH of the solution is adjusted by addition of carbonate, carbonate or hydroxide of an alkali metal Palladium / carbon hydride catalyst. 13. The method of claim 12, The process for producing the palladium / carbon hydride catalyst Wherein said cationic surfactant is selected from the group consisting of sodium polyoxyethylene dodecyl ether sulfate, potassium polyoxyethylene dodecyl ether sulfate, sodium polyoxyethylene dodecyl ether phosphate and potassium polyoxyethylene dodecyl ether phosphate Palladium / carbon hydride catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In step (c), the step of supporting palladium on the pre-impregnated activated carbon particles may be carried out by impregnating the solution with the solution at 0 to 50 DEG C for 0.5 to 6 minutes or at a pressure of 5 to 20 mL / spraying said solution onto said pre-impregnated activated carbon particles at a rate of at least 10 minutes per minute Palladium / carbon hydride catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In step (e), the reducing agent is selected from the group consisting of formic acid, sodium formate, formic aldehyde, hydrazine hydrate, glucose, hydrogen, and mixtures thereof Palladium / carbon hydride catalyst. 9. The method according to claim 7 or 8, The process for producing the palladium / carbon hydride catalyst In step (b '), the inorganic acid used in the washing step has a concentration of 0.1 to 0.5N and is selected from the group consisting of hydrochloric acid, nitric acid, phosphoric acid, and mixtures thereof, The drying step is carried out at 100 to 200 ° C Palladium / carbon hydride catalyst. delete