KR20050073926A - Method for regenerating silica supported ruthenium catalysts - Google Patents

Abstract

Disclosed is a method for regenerating a ruthenium catalyst supported on silica. In the method for regenerating a ruthenium catalyst supported on silica according to the present invention, a catalyst having reduced selectivity in the process of producing hydrogenated bisphenol-A by continuously hydrogenating bisphenol-A in the presence of a ruthenium catalyst supported on silica, The dissolved organic solvent is used for treatment under a temperature of normal temperature or higher and a pressure of from normal pressure to 200 atmospheres. According to the present invention, it is possible to regenerate and reuse a catalyst that has been reduced in selectivity and cannot be used without any other facility, thereby maximizing the use time of the catalyst, and can be easily applied to a continuous reaction using a fixed bed reactor.

Description

Method for regenerating silica supported ruthenium catalysts

The present invention relates to a regeneration method of a ruthenium catalyst supported on silica, and more particularly, to a hydrogenated bisphenol-A by continuously hydrogenating bisphenol-A (hereinafter referred to as 'BPA') in the presence of a ruthenium catalyst supported on silica. It relates to a method for regenerating the selectivity of the catalyst by treating the catalyst having a reduced selectivity in the process of preparing a amine in an organic solvent in which the amine is dissolved under a temperature above normal temperature and a pressure of from atmospheric pressure to 200 atm.

Hydrogenated bisphenol-A, ie 2,2-bis (4-hydroxycyclohexyl) propane (hereinafter referred to as 'HBPA') is a useful material as a polymer raw material. For example, the polyether resin obtained by polycondensing HBPA with dibasic acids such as phthalic acid and maleic acid has heat resistance and moisture resistance, and the epoxy resin obtained by reacting HBPA with epichlorohydrin has excellent electrical properties. Since there is no aromatic ring and there is little yellowing property, it is used where weather resistance is required, and it has the advantage of good operability in low viscosity.

To prepare HBPA, the addition of hydrogen to the aromatic ring of BPA in the presence of a metal supported catalyst has been studied by several researchers for decades. Examples of the prior art using a metal supported catalyst for the BPA catalytic hydrogenation reaction are as follows.

US Pat. No. 5,936,126 discloses a reaction of an organic compound in the presence of a ruthenium or a catalyst in which at least one of Group IB, Group VIIB, Group VIIIB metals is supported on a support, wherein the support is activated carbon, silicon carbide, alumina, Silica, titania, zirconia, magnesium oxide, zinc oxide and the like are used, the average pore diameter is at least 50 nm, the BET surface area is 30 m ² / g or less, and the ruthenium content is 0.01 to 30% by weight based on the total weight of the catalyst. Disclosed is a point having a range. U.S. Pat.No. 5,942,645 also discloses a process for hydrogenating aromatic compounds in the presence of a ruthenium supported catalyst, wherein activated carbon, silicon carbide, having an average pore diameter of at least 0.1 μm and a BET surface area of 15 m ² / g or less, Large multi-process supports such as alumina, silica, titania, zirconia, magnesium oxide, and zinc oxide are used. However, all of these examples use batch reactors, and there is no mention of catalyst life.

As a technique for producing HBPA using a fixed bed reactor, Japanese Patent Laid-Open No. 6-9461 discloses a method of hydrogenating bisphenols such as BPA in a C ₄ or higher secondary alcohol (eg, octanol) solvent in the presence of a ruthenium catalyst. At this time, ruthenium is supported by using alumina, silica, titania, or the like. In particular, when a ruthenium catalyst supported on alumina was used, HBPA was obtained at a yield of 94.8% in a fixed bed reactor under a temperature of 140 ° C., a hydrogen pressure of 50 kg / cm ² , and LHSV 1 h ⁻¹ , and was operated for 600 hours. It also mentions no deactivation.

However, despite many researches on the hydrogenation reaction of BPA, the development of steadily related technologies until recently is evidence that there are still many deficiencies in industrial use of these technologies. According to the results of reproducing experiments, it was confirmed that in most cases, it is difficult to obtain high economic results in consideration of the price of the catalyst, the reaction yield of HBPA, the operating time, and, in particular, there was a limit in increasing the reaction yield of HBPA.

The inventors of the present invention, in particular, to investigate the cause of the decrease in the yield of the HBPA reaction, as a result, when the hydrogenation reaction of BB in the presence of a metal supported catalyst, the decrease in the reaction yield of HBPA is contained in HBPA during the hydrogenation reaction One or two of the two hydroxyl groups are dehydrated to produce unwanted substances, and this side reaction is found to be related to the acid strength of the catalyst support itself. That is, as the acid strength of the catalyst support increases, the dehydration reaction is promoted during the hydrogenation reaction, thereby decreasing the reaction yield of HBPA.

In order to solve this problem, the present inventors have devised a method of producing HBPA with high efficiency and high yield by reducing side reactions during catalytic hydrogenation by preparing a catalyst using a silica support having an acid strength index of 10% or less (Korea Patent Publication 2002) -0074578). The acid strength index is 2 in the case of adding 1 g of catalyst to a fixed bed reactor and passing a gas consisting of 5 vol% 2-propanol and 95 vol% helium at 200 ° C. at a rate of 50 ml / min based on the helium flow rate. It is defined as the conversion rate of propanol.

A catalyst prepared by supporting ruthenium on a silica support having a weak acid strength was charged in a fixed bed reactor, and a continuous hydrogenation reaction of BPA was carried out under conditions of a temperature of 150 ° C., a hydrogen pressure of 100 kg / cm ² , and LHSV 2 h ⁻¹ . HBPA An average yield of 96% was obtained, which showed no significant decrease in activity and selectivity until the reaction for 500 hours. In the continuous reaction using the catalyst of the Republic of Korea Patent Publication, the activity and selectivity of the catalyst is maintained until the reaction for 1,500 hours, it was possible to manufacture HBPA with a high economical compared to the case of using the catalyst of the prior art.

However, it was found that the selectivity of the catalyst gradually decreased after continuous reaction for about 1,500 hours or more in the presence of the catalyst of the Republic of Korea Patent Publication. In other words, the conversion rate of BPA was maintained at 100%, but the selectivity of HBPA gradually decreased below 95%. This is not due to poisoning caused by catalyst poison, which is a common cause of general metal catalyst deactivation, or reduced selectivity by carbon deposition, but silanol groups are formed on the surface of the silica support due to the small amount of water continuously generated from the dehydration reaction of BPA during the reaction. It was judged that the catalyst surface gradually became acidified. This fact was proved by the phenomenon that the HBPA selectivity of the catalyst rapidly decreased when the reaction was carried out using a reaction solvent having a high moisture content of 3,000 ppm or more. As described above, the acidified catalyst promotes dehydration during the hydrogenation of BPA, thereby reducing the reaction yield of HBPA.

The ruthenium catalyst loaded on silica, which had decreased selectivity due to acidification of the surface, could not increase the selectivity by increasing the reaction temperature or increasing the reaction pressure during the reaction. If the reaction selectivity of HBPA is lowered to 95% or lower, an additional recrystallization process is required to increase the purity and the economic efficiency of the process must be replaced, and thus the catalyst must be replaced.

If the catalyst with reduced selectivity can be regenerated and reused, the utilization of expensive precious metal catalysts can be increased, thereby increasing the economics of the process. However, although efforts have been made to solve the deactivation by catalyst poison or carbon deposition in the hydrogenation reaction using a metal catalyst, efforts to solve the problem due to acidification of the catalyst surface during the hydrogenation reaction have been difficult to find, requiring a new technique. In particular, in the conventional HBPA production method, there was no example of using the catalyst for a long time more than 1,500 hours in the continuous hydrogenation reaction, and in other hydrogenation reactions, the silica-supported ruthenium catalyst was used for a long time or due to factors due to the influence of moisture in the reaction solvent. When the selectivity decreased, no change was found in the state of the catalyst and no improvement was found.

The present inventors have tried various methods to regenerate the selectivity of a catalyst whose selectivity was lowered after a long time reaction in a continuous hydrogenation reaction of BPA using a ruthenium catalyst supported on silica or during the reaction due to the influence of moisture in the reaction solvent. As described above, the reaction temperature and pressure were gradually increased during the reaction to compensate for the selectivity of the lowered catalyst, but the selectivity was lowered. In addition, the catalyst was treated at high temperature while flowing argon, nitrogen, oxygen, or a mixture thereof, or neutralized with IA or Group IIA metal ion solution of the periodic table, but all were less effective in regenerating the selectivity of the catalyst. .

In contrast, the present inventors have found that by treating a ruthenium catalyst supported on silica with reduced selectivity with an organic solvent in which amine is dissolved, it is possible to regenerate the selectivity of the catalyst to its initial state without installing additional facilities in the process. The present invention has been completed based on this.

Accordingly, an object of the present invention, in the production of HBPA at high efficiency and low cost, the ruthenium catalyst supported on silica with reduced selectivity during the reaction is an organic solvent in which the amine is dissolved, the temperature of the above room temperature and atmospheric pressure to 200 atm It is to provide a method for simply regenerating the selectivity of the catalyst by treating under pressure.

The method for regenerating a ruthenium catalyst supported on silica according to the present invention for achieving the above object has a selectivity in a process for producing hydrogenated bisphenol-A by continuously hydrogenating bisphenol-A in the presence of a ruthenium catalyst supported on silica. The reduced catalyst is characterized in that the organic solvent in which the amine is dissolved is treated at a temperature above normal temperature and under a pressure of from atmospheric pressure to 200 atm.

When the selectivity of HBPA defined as the ratio of HBPA in the total reaction product decreases to 90% or less in the continuous hydrogenation process, it is determined that the selectivity of the catalyst is reduced to regenerate the catalyst.

The regeneration method of the catalyst may be carried out by removing the catalyst from the reactor, treating it with an organic solvent in which an amine is dissolved, and then loading the catalyst again. However, since the reactor operation is stopped for a long time before and after regeneration, economic efficiency of the process is lowered. In addition, the method of regenerating the catalyst may be performed by dissolving an amine in the reaction raw material, but the method may be carried out continuously. However, since the process requires removing the amine from the HBPA after the reaction, the amount of amine used increases, thereby lowering the economic efficiency of the process. . Therefore, a method of treating this with an organic solvent in which an amine is dissolved in a state where a catalyst having a reduced selectivity is loaded in a reactor is preferable because the catalyst and the amine are not exposed to the atmosphere and the time required for the regeneration treatment is short.

There is no great restriction on the regeneration treatment temperature of the catalyst in the regeneration method of the catalyst according to the present invention. If the organic solvent and the amine are treated at a temperature higher than or equal to the temperature at which the liquid phase is maintained, a sufficient regeneration effect can be seen. It is preferable to perform the regeneration treatment in the temperature range of the hydrogenation reaction of BPA in terms of saving time in controlling the reactor temperature before and after the catalyst regeneration treatment process.

The regeneration treatment pressure of the catalyst in the regeneration method of the catalyst according to the present invention is not particularly limited, and a pressure of normal pressure to 200 atm is sufficient. If the processing pressure is a high pressure of more than 200 atmospheres because expensive equipment is required to maintain the pressure, there is a problem that reduces the economics of the process. It is preferable to perform the regeneration treatment in the pressure range of the hydrogenation reaction of BPA in terms of saving time in reducing or filling the reactor pressure before and after the regeneration treatment process.

Although the regeneration treatment time of the catalyst in the regeneration method of the catalyst according to the present invention varies depending on the basicity of the amine used and the weight space velocity of the organic solvent in which the amine is dissolved, an amine having a basicity constant (pK _b ) of 4 or less is used. And when the weight space velocity of the organic solvent in which the amine is dissolved is 2 h ^-1 , it is treated for 2 hours to 10 hours, preferably 2 hours to 4 hours. If the treatment time is longer than 10 hours, the performance of the catalyst is less affected, but it causes unnecessary treatment cost and time consuming. As the treatment time is less than 2 hours, the catalyst regeneration effect is smaller.

The amine is one selected from aliphatic amines and aromatic amines of primary amines, secondary amines and tertiary amines, and diamines. The aliphatic amines have 1 to 10 carbon atoms in the alkyl group substituted with hydrogen of the amine. Examples of the amine include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, n-propylamine, dipropylamine, tripropylamine, n-butylamine, aniline, N-methylaniline , N, N-dimethylaniline, ethylenediamine, diaminopropane, diaminobutane, hexamethylenediamine, pyridine, pyrrolidine, ethanolamine and the like.

Since the amine is diluted with an organic solvent and used, it is preferable to dissolve well in an organic solvent. Among them, the smaller the basicity constant (pK _b ), the greater the basicity, the greater the effect. Ammonia water may also be used for regeneration of the catalyst, but it is difficult to handle in the hydrogenation process and difficult to quantitatively dissolve in an organic solvent, and thus does not have a great effect on regeneration of the catalyst.

The concentration of amines depends on the basicity of the organic solvent, but is usually at a concentration of 0.2% to 2% by weight. If the concentration of the amine is higher than 2% by weight, the physical properties of the silica, which is a support, affect the physical properties, and excessive amine is used for the regeneration treatment. Longer or reduced catalyst regeneration effect. When the basic constant (pK _b ) of the organic solvent is lower than 4, use of an amine having a concentration of 0.5% by weight is effective for catalyst regeneration.

The organic solvent is not particularly limited as long as it dissolves amine well. For example, alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and the like, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate and the like As aldehydes, dimethyl ether, diethyl ether, ethyl methyl ether, diphenyl ether, propylene glycol monomethyl ether, etc., which are represented by representative acetates, formaldehyde, propionaldehyde, benzylaldehyde, butylaldehyde, isobutyl aldehyde, etc. Representative ethers, ketones represented by methyl isobutyl ketone, diisobutyl ketone, methyl ethyl ketone, acetone, methyl-n-butyl ketone, ethyl butyl ketone and the like and 1,4-dioxane, tetrahydrofuran, acetonitrile One or a mixture thereof selected from the group consisting of organic solvents such as these may be used as the solvent.

Since the steps such as washing the reactor before and after the catalyst regeneration step can be omitted and a separate solvent separation facility is not required, the same organic solvent as the organic solvent used for the hydrogenation step of BPA is used for the catalyst regeneration step. desirable.

In addition, as described above, when the water content in the solvent exceeds 3,000 ppm during the hydrogenation reaction, acidification of the surface of the silica support is promoted, thereby increasing side reactions due to the dehydration reaction. Therefore, the lower the water content of the organic solvent used for the catalyst regeneration, good. For example, the water content in the organic solvent is 3,000 ppm or less, preferably 1,000 ppm or less, which is effective for catalyst regeneration.

In order to regenerate the catalyst with the catalyst loaded in the reactor, it is preferable to wash the catalyst and the reactor before and after regeneration using an organic solvent containing no amine. This is because unnecessary side reactions between raw materials and amines remaining in the reactor before regeneration and amines remaining in the reactor after regeneration can be minimized. Since the concentration of the amine used for regeneration is low, the washing time using an organic solvent is sufficient within 4 hours.

The catalyst used in the present invention is a catalyst in which ruthenium is supported on a silica support having an acid strength index of 10% or less, and the support silica is selected from natural silica, synthetic silica, silica gel, and pyrogenic silica (trade name; aerosil, carbosil). If the acidity index is 10% or less and the surface area is 50 to 500 m ² / g, there is no particular limitation. The acid strength index is 2 in the case of adding 1 g of catalyst to a fixed bed reactor and passing a gas consisting of 5 vol% 2-propanol and 95 vol% helium at 200 ° C. at a rate of 50 ml / min based on the helium flow rate. It is defined as the conversion rate of propanol.

In addition, the ruthenium catalyst supported on the silica used in the present invention is prepared by dissolving ruthenium in a salt state in water and then supporting it on silica by a generally known method, and the amount of ruthenium is 0.1 to 20 based on the total weight of the catalyst. Weight percent. The catalyst carrying the ruthenium salt is calcined in the air at 300 ° C. to 600 ° C. to decompose the salt, and then stored. The catalyst is used after reduction to 100 ° C. to 500 ° C. in a reducing agent atmosphere such as hydrogen before the reaction. Ruthenium salts used in the preparation of catalysts include ruthenium chloride, ruthenium nitrosylnitrate, ruthenium acetylacetonate, and the like, and there are no particular restrictions on the salt form.

On the other hand, the catalyst regeneration method according to the present invention can also be used for the regeneration of the silica support catalyst having reduced activity and selectivity due to surface acidification during the reaction.

Hereinafter, the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Example 1

A stainless steel tubular fixed bed reactor having an internal diameter of 10 mm and a capacity of 80 cc was filled with a silica catalyst loaded with 1% by weight (based on the total weight of the catalyst) of ruthenium in a tubular fixed bed reactor made of 3 mm pellets, and then hydrogenated 20 cc / It fed at the speed | rate of min, and heated up to 400 degreeC, and performed reduction. After the reduction, the amount of hydrogen was adjusted to be 6 mole times the amount of BPA added, and the temperature and the reaction pressure of the reactor were maintained at 150 ° C. and 100 kg / cm ² , respectively. Then, the reaction was started while introducing the reaction raw materials at a weight space velocity of 2 h ⁻¹ . As a reaction raw material, 20 wt% BPA dissolved in 2-propanol was used, and the reaction product was analyzed by gas chromatograph with a flame ionization detector. As a result, the average conversion of BPA was 100% and the average selectivity of HBPA was more than 95% for 1,500 hours after the start of the reaction. After the reaction for 1,500 hours, 2-propanol was added for 4 hours at a weight space velocity of 2 h ⁻¹ while maintaining the reaction temperature and pressure to wash the catalyst having the average selectivity of HBPA reduced to 90%. Then, catalyst regeneration was carried out by adding 2-propanol (1,000 ppm water content) in which 0.5% by weight of triethylamine was dissolved at a weight space velocity of 2 h ⁻¹ while maintaining the reaction temperature and pressure. It was. After the regeneration, 2-propanol was added again for 4 hours at a weight space velocity of 2 h ^-1 , and then, the reaction raw material in which 20 wt% BPA was dissolved in 2-propanol was added at a weight space velocity of 2 h ^-1 . The reaction was resumed. As a result of the continuous reaction after the catalyst regeneration, the conversion of BPA was 100%, the selectivity of HBPA was 96%, and then the average selectivity of HBPA was maintained above 95% for 1,000 hours continuous reaction.

Examples 2-7

The catalyst having reduced HBPA selectivity to 90% was regenerated by the same regeneration procedure as in Example 1, and the types of amines dissolved in 2-propanol (water content of 1,000 ppm) were tripropylamine, ethanolamine, pyridine, and fatigue, respectively. Catalyst regeneration was carried out with lidine, ethylenediamine and diaminobutane. The catalyst regeneration was observed by continuous reaction for 100 hours after the catalyst regeneration, and the catalyst regeneration results according to the respective amines are summarized in Table 1 below.

Example 8

Regeneration was carried out through the same regeneration procedure as in Example 1, except that the catalyst having reduced selectivity of HBPA to 90% was used with a 2-propanol (1,000 ppm water content) solution in which triethylamine was dissolved at a concentration of 0.25% by weight. . The results of the continuous reaction for 100 hours after the catalyst regeneration are summarized in Table 1 below.

Catalyst Regeneration Results According to the Amine Used in Examples 2-8 Amine BPA Avg. Conversion Rate (%) HBPA Average Selectivity (%) Example 2 Tripropylamine 100 95.5 Example 3 Ethanolamine 100 95.3 Example 4 Pyridine 100 94.6 Example 5 Pyrrolidine 100 94.3 Example 6 Ethylenediamine 100 94.6 Example 7 Diaminobutane 100 94.5 Example 8 Triethylamine 99.5 94.2

Example 9

In the same manner as in Example 1, the catalyst was regenerated using a 2-propanol (water content 1,000 ppm) solution in which triethylamine was dissolved at a concentration of 0.5% by weight, followed by continuous reaction for 100 hours, and then At a reaction temperature and a reaction pressure, 2-propanol containing 4,000 ppm of water was added at a weight space velocity of 2 h ⁻¹ for 50 hours to artificially reduce the HBPA selectivity of the catalyst to 83%. The catalyst with reduced selectivity was regenerated in the same manner as in the catalyst regeneration method of Example 1, and the procedure of the reaction experiment for 100 hours was repeated. As a result of repeating the catalyst deactivation and regeneration experiments seven times, it was confirmed that the HBPA selectivity of the catalyst was regenerated to 95% or more every regeneration.

Comparative Example 1

Using a 2-propanol (water content 1,000 ppm) solution in which 0.5% by weight of ammonia water was dissolved, a catalyst having a 90% reduction in HBPA selectivity was regenerated in the same manner as in Example 1. As a result of reaction experiments under the same reaction conditions as in Example 1 after regeneration, the conversion of BPA was 100%, and the selectivity of HBPA was 93%.

Comparative Example 2

Using 2-propanol (water content 1,000 ppm) in which 0.5 wt% sodium nitrate was dissolved, a catalyst having a 90% reduction in HBPA selectivity was regenerated in the same manner as in Example 1. In the same reaction conditions as in Example 1 after regeneration, the conversion of BPA was 56%, the selectivity of HBPA was 35%, and the selectivity of the hydrogenated product of only one of the two aromatic rings of BPA was 54%. It was.

Comparative Example 3

After the catalyst with reduced selectivity of HBPA to 90% was washed with 2-propanol, nitrogen was added at a rate of 20 cc / min and dried at room temperature and atmospheric pressure. Then, a gas mixed with 3% by volume of oxygen and 97% by volume of nitrogen was charged at a rate of 100 cc / min, and regenerated by raising the temperature to 400 ° C. at atmospheric pressure. After the regeneration, the temperature was controlled to room temperature, hydrogen was charged at a rate of 20 cc / min, and the catalyst was reduced at a temperature of 400 ° C. under the same reaction conditions as in Example 1, and the conversion rate of BPA was 100%. HBPA had a selectivity of 55% and only one of the two aromatic rings of BPA had a 31% selectivity for the hydrogenated product.

As described above, the ruthenium catalyst supported on the silica having reduced selectivity through the regeneration method of the catalyst according to the present invention can be repeatedly used without a separate regeneration facility, and in particular, a continuous hydrogenation reaction using a fixed bed reactor It can be easily applied to have the advantage of increasing the economics of the process. In addition, it is possible to achieve the effect that can be produced in high yield and low cost through this.

While specific embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Anyone of ordinary skill in the art can make various modifications, as well as such modifications are within the scope of the claims.

Claims (11)

A catalyst having reduced selectivity in the process of producing hydrogenated bisphenol-A by continuously hydrogenating bisphenol-A in the presence of a ruthenium catalyst supported on silica, using an organic solvent in which an amine is dissolved, at a temperature above normal temperature and a pressure of 200 to 200 A method for regenerating a ruthenium catalyst supported on silica, which is carried out at a pressure of atmospheric pressure. The method of regenerating a ruthenium catalyst supported on silica according to claim 1, wherein the treatment is performed while a catalyst having a reduced selectivity is loaded in the reactor. The method for regenerating a ruthenium catalyst supported on silica according to claim 1 or 2, wherein the treatment is carried out at the same temperature and pressure as the temperature and pressure in the hydrogenation reaction. The method of claim 1, wherein the amine is one selected from aliphatic amines and aromatic amines of primary amines, secondary amines and tertiary amines, and diamines, and the aliphatic amines have hydrogen atoms of amines and carbon atoms of alkyl groups substituted with them. Regeneration method of a ruthenium catalyst supported on silica, characterized in that 1 to 10. The method of claim 4, wherein the amine is methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, n-propylamine, dipropylamine, tripropylamine, n-butylamine, aniline, N Regeneration of a ruthenium catalyst supported on silica, which is one selected from -methyl aniline, N, N-dimethylaniline, ethylenediamine, diaminopropane, diaminobutane, hexamethylenediamine, pyridine, pyrrolidine, and ethanolamine Way. The method of regenerating a ruthenium catalyst supported on silica according to claim 1, wherein the concentration of the amine dissolved in the organic solvent is 0.2 to 2 wt% based on the total solution. The method of regenerating a ruthenium catalyst supported on silica according to claim 1, wherein the water content of the organic solvent used to dilute the amine is 3,000 ppm or less. 8. The method of regenerating a ruthenium catalyst supported on silica according to claim 7, wherein the water content of the organic solvent used to dilute the amine is 1,000 ppm or less. The method of regenerating a ruthenium catalyst supported on silica according to claim 1, wherein the organic solvent used to dilute the amine is the same organic solvent as the organic solvent used in the hydrogenation reaction. The ruthenium catalyst supported on the silica is selected from the group consisting of natural silica, synthetic silica and pyrogenic silica, has an acid strength index of 10% or less, and a surface area of 50 to 500 m ² / g. A method for regenerating a ruthenium catalyst supported on silica, wherein the silica is a catalyst having 0.1 to 20% by weight of ruthenium on a total weight of the catalyst. The method of regenerating a ruthenium catalyst supported on silica according to claim 1, further comprising washing the catalyst and the reactor before and after regeneration using an organic solvent that does not contain an amine.