CATALYST FOR HYDROGENATION OF AROMATIC COMPOUND AND PREPARATION METHOD THEREFOR

Abstract

The present invention relates to a catalyst for hydrogenation of an aromatic compound, which is capable of greatly reducing the inactivation of a catalyst by using a support including a magnesium-based spinel structure, and a preparation method therefor.

Claims

1. A catalyst for hydrogenation of an aromatic compound, the catalyst comprising a catalytically active component and a support, wherein the catalytically active component includes Formula 1 having a magnesium-based spinel structure:
Mg.sub.xAl.sub.2O.sub.3+x[Formula 1] wherein x is an integer from 0.1 to 1.0.

2. The catalyst of claim 1, wherein the catalyst comprises at least one active metal selected from the group consisting of ruthenium, palladium, rhodium, platinum, nickel, and any mixture thereof.

3. The catalyst of claim 2, wherein an amount of the active metal is in a range of 0.1 wt % to 10 wt %.

4. The catalyst of claim 1, wherein ruthenium (Ru) or ruthenium oxide (RuO.sub.2) is supported on the support having the spinel structure.

5. The catalyst of claim 4, wherein the support comprises 0 wt % to 5 wt % of magnesium oxide (MgO).

6. The catalyst of claim 1, wherein the catalyst is in at least one form selected from powder, particle, granular, and molded supports.

7. The catalyst of claim 1, wherein the catalytically active component is supported on the support in a form of a metal salt solution.

8. The catalyst of claim 1, wherein the catalyst is an egg-shell type catalyst.

9. The catalyst of claim 8, wherein the egg-shell type catalyst has a pore volume of 0.1 ml/g to 1.5 ml/g and a BET surface area of 10 m.sup.2/g to 300 m.sup.2/g.

10. The catalyst of claim 1, wherein a Mg/Al molar ratio is 1:0.0625 to 1:0.5.

11. A hydrogenation method of an aromatic compound, characterized by being used for hydrogenation of an organic compound containing an aromatic ring by using the catalyst according to claim 1.

12. Di(2-ethylhexyl)cyclohexane-1,4-dicarboxylate (DEHCH) prepared by the hydrogenation method of the catalyst according to claim 11.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0029] FIG. 1 is a graph showing a result of XRD analysis of a Mg-introduced spinel support according to the present invention.

[0030] FIG. 2 is a graph showing a result of a reaction experiment for each support during the preparation of a catalyst according to the present invention.

BEST MODE

[0031] The present invention will be described with reference to specific embodiments and the accompanying drawings. The embodiments will be described in detail in such a manner that the present invention may be carried out by those of ordinary skill in the art. It should be understood that various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain shapes, structures, and features described herein may be implemented in other embodiments without departing from the spirit and scope of the present invention in connection with one embodiment.

[0032] Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims and the entire scope of equivalents thereof, if properly explained.

[0033] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, so that those of ordinary skill in the art can easily carry out the present invention.

[0034] As described above, when the conventional egg-shell type catalyst used in the hydrogenation process is inactivated during the hydrogenation reaction according to the type of the catalyst, causing the cost of catalyst replacement, the reduction in operating time, and the like.

[0035] In the present invention, the solution to the above-described problems has been sought by including a support including a magnesium-based spinel structure to significantly reduce inactivation of a catalyst by hydrogenating aromatics in an organic compound.

[0036] The present invention provides a catalyst for hydrogenation of an aromatic compound, wherein the catalyst includes a catalytically active component and a support, and the catalytically active component includes Formula 1 having a magnesium-based spinel structure.

Mg.sub.xAl.sub.2O.sub.3+x[Formula 1]

[0037] wherein x is an integer from 0.1 to 1.

[0038] According to the present invention, the catalytically active component may be supported on the support in the form of a metal salt solution.

[0039] Specifically, the support includes at least one active metal selected from the group consisting of ruthenium, palladium, rhodium, platinum, nickel, and any mixture thereof. An amount of the active metal may be in a range of preferably 0.1 wt % to 10 w %, and more preferably 0.3 wt % to 5 wt %.

[0040] According to the present invention, the support may be supported on the support having the spinel structure, for example, ruthenium (Ru) or ruthenium oxide (RuO.sub.2). The support may include 0 wt % to 5 wt % of magnesium oxide (MgO).

[0041] At this time, when the magnesium oxide (MgO) is included in excess of 5 wt %, the activity of the catalyst may be reduced, or a side reaction may occur. Therefore, the above range is particularly preferable.

[0042] On the other hand, the catalyst according to the present invention may be in the powder, particle, granular, or molded form. Preferably, the catalyst according to the present invention is in the molded form.

[0043] Hereinafter, the structure and operation of the present invention will be described in more detail with reference to preferred examples of the present invention. However, these example are shown by way of illustration and should not be construed as limiting the present invention in any way.

[0044] Since contents not described herein can be sufficiently technically inferred by those of ordinary skill in the art, descriptions thereof will be omitted.

EXAMPLES

<Example 1> Preparation of Mg.SUB.x.Al.SUB.2.O.SUB.3+x .Support Having Spinel Structure

[0045] In order to adjust a Mg/Al molar ratio to a desired ratio in an alumina pellet support for structural transformation (1:2 for MgAl.sub.2O.sub.4 spinel), a necessary magnesium precursor and an aqueous solution in which the magnesium precursor was dissolved in excess distilled water were added and dried in a forced convection hot air oven at 120 C. Then, the dried support was calcined at a constant temperature in an electric furnace under air flow and slowly cooled to room temperature to finally obtain a Mg.sub.xAl.sub.2O.sub.3+x support having a spinel structure. An XRD analysis was performed on the structure of the support manufactured in this manner and results thereof are shown in FIG. 1. The results of nitrogen adsorption/desorption of the support and the pore volume calculation results obtained through water absorption are shown in Table 1 below.

TABLE-US-00001 TABLE 11 Specific surface Pore volume Support area (m.sup.2/g) (cm.sup.3/g) -Al.sub.2O.sub.3 237.1 1.01 Mg.sub.0.25Al.sub.2O.sub.x 203.7 0.95 Mg.sub.0.5Al.sub.2O.sub.x 160.2 0.84 MgAl.sub.2O.sub.x 100.5 0.68

[0046] As shown in FIG. 1, in the case of -alumina, peaks exist at about 32.6, 37, 39.2, 45 to 46, and 67, and in the case of the structurally transformed support, peaks exist at about 19, 31.5, 45, 59.5, and 66. Thus, it can be confirmed that as the amount of Mg introduced increased, the structure was transformed into the spinel structure.

<Example 2> Preparation of Catalyst in which Ruthenium Nanoparticles were Supported on Support

[0047] A ruthenium precursor was measured so that a weight of ruthenium in a supported catalyst became 1 wt %. A volume of an aqueous solution was adjusted so as to be 97% of a pore volume of a support (alumina or structurally transformed Mg.sub.xAl.sub.2O.sub.3+x support). Then, a precious metal was supported on the support through an incipient wetness impregnation method. The supported catalyst was dried in a forced convection hot air oven at 120 C. The dried catalyst was calcined at 400 C. in an electric furnace under air flow and slowly cooled to room temperature to finally obtain a catalyst in which ruthenium was supported on the support.

<Example 3> DOTP (Dioctyl Terephthalate) Hydrogenation Reaction in Batch Reactor Using Catalyst Prepared Through the Above Method

[0048] 6 cc of the catalyst prepared in Example 2 was filled in a catalyst basket mounted on a magnedrive. In a 300-mL batch reactor (autoclave), a reaction was performed with a 250-mL dioctyl terephthalate solution at 150 bar H.sub.2 at a temperature of 180 C. for 1 hour and 30 minutes. After the reaction, the hydrogen pressure was released and the product was removed from the reactor. The same amount of DOTP was put again and a reaction was performed again several times. By using this, a conversion rate of the catalyst in a continuous batch reactor was measured and results thereof are shown in FIG. 2.

Comparative Example

<Comparative Example 1> Preparation of Catalyst in which Ruthenium Nanoparticles were Supported on -Alumina Support

[0049] A ruthenium precursor was measured so that a weight of ruthenium in a -alumina support became 1 wt %. A volume of an aqueous solution was adjusted so as to be 97% of a pore volume of the support. Then, a precious metal was supported on the support through an incipient wetness impregnation method. Then, the supported catalyst was dried in a forced convection hot air oven at 120 C. The dried catalyst was calcined at 400 C. in an electric furnace under air flow and slowly cooled to room temperature to finally obtain a catalyst in which ruthenium was supported on the support.

Experimental Example

[0050] A Mg(NO.sub.3).sub.2 aqueous solution was added to an Al.sub.2O.sub.3 alumina support and dried and calcined to prepare a catalyst support having a Mg.sub.xAl.sub.2O.sub.3+x type spinel structure. The support was supported with a RuNO(NO.sub.3).sub.3 aqueous solution and drying calcination was performed thereon to prepare a RuO.sub.2/Mg.sub.xAl.sub.2O.sub.3+x catalyst. The prepared catalyst was used to perform a hydrogenation reaction on DOTP (dioctyl terephthalate) in an autoclave and a trickle bed reactor to prepare DEHCH (di(2-ethylhexyl)-1,4-cyclohexane dicarboxylate).

[0051] As shown in Table 2 below, as a result of observing catalyst inactivation according to the number of times of reactions in an autoclave reaction, it was confirmed that the inactivation of the catalyst supported using - and -alumina as a support appeared rapidly, but in the present invention, the inactivation expressed as a decrease in the average conversion rate of the catalyst prepared using Mg.sub.xAl.sub.2O.sub.3+x or MgOMg.sub.xAl.sub.2O.sub.3+x as a support was significantly reduced.

TABLE-US-00002 TABLE 2 Reduction in average conversion rate Max Min (Inactivation Number Number degree) Ini Max of Min of (%)/number Catalyst conv. conv. times conv. times of times Ru/-Al.sub.2O.sub.3 48 57 3 51 6 2.0 Ru/-Al.sub.2O.sub.3 56 64 2 44 9 2.8 Ru/MgAl.sub.2O.sub.x(MgO)- 18.5 36.3 6 33.8 18 0.2 C700 Ru/MgAl.sub.2O.sub.x(S.S)- 13.9 34 9 31.8 22 0.2 C700 Ru/Mg.sub.0.125Al.sub.2O.sub.x- 24.9 45.9 7 42.9 18 0.3 C350

[0052] While the present invention has been described by particular matters such as specific components and limited embodiments and drawings, this is provided only for helping the comprehensive understanding of the present invention. The present invention is not limited to the above-described embodiments, and it will be understood by those of ordinary skill in the art that various modifications and variations can be made thereto without departing from the scope of the present invention.

[0053] Therefore, it will be understood that the spirit of the present invention should not be limited to the above-described embodiments and the claims and all equivalent modifications fall within the scope of the present invention.