KR101786910B1 - Preparation method of 1,4-cyclohexanedimethanol - Google Patents

Abstract

Reducing terephthalic acid in the presence of a first metal catalyst comprising a palladium (Pd) compound immobilized on a dealuminated zeolite carrier; A ruthenium (Ru) compound, a tin (Sn) compound and a platinum (Pt) compound fixed on a dealuminated zeolite carrier in a weight ratio of 1: 0.8 to 1.2: And reducing the reduction product of terephthalic acid in the presence of a metal catalyst to produce 1,4-cyclohexanedimethanol.

Description

PREPARATION METHOD OF 1,4-CYCLOHEXANEDIMETHANOL < RTI ID = 0.0 >

The present invention relates to a process for preparing 1,4-cyclohexanedimethanol. More particularly, the present invention relates to a process for producing 1,4-cyclohexanedimethanol with high purity, while simplifying the reaction process to increase the efficiency and economy of the reaction and minimize the by-products in a shorter time .

The process for preparing 1,4-cyclohexanedimethanol, which is conventionally known, It can be summarized as branches. One method is to synthesize 1,4-cyclohexanedimethanol via 1,4-dimethylcyclohexanedicarboxylate using dimethyl terephthalate under high temperature and high pressure conditions, and the other method uses terephthalic acid Thereby synthesizing 1,4-cyclohexane dicarboxylic acid and preparing 1,4-cyclohexanedimethanol from the 1,4-cyclohexane dicarboxylic acid.

However, the previously known method for preparing 1,4-cyclohexane dimethanol requires additional steps for removing or recovering the byproducts generated during the commercialization of the process or the catalysts used in each stage, and the resulting 1,4- The purity or reaction efficiency of hexane dimethanol was not so high.

Japanese Unexamined Patent Application, First Publication No. 2002-145824 discloses a process wherein a terephthalic acid is subjected to a hydrogenation reaction in the presence of a solvent and a palladium catalyst to obtain an intermediate 1,4-cyclohexane dimethanol, followed by a further hydrogenation reaction to obtain 1,4- A process for producing dimethanol is disclosed. However, such a preparation method lowers the selectivity of 1,4-cyclohexanedimethanol produced by-products to be finally prepared, and accordingly, an aliphatic higher alcohol such as 2-ethylhexanol is used as an extracting agent, A process of separating and recovering alcohol was required.

European Patent No. 0934920 discloses a preparation process for producing Raney catalyst to reduce terephthalic acid. However, the above-mentioned production method uses a catalyst which is not easy to use on a large scale, and a separate separation and recovery equipment process is further required by using dioxane together with water as a reaction solvent.

U.S. Patent No. 6,294,703 discloses a method for synthesizing 1,4-cyclohexanedimethanol with a complex catalyst comprising 1,4-cyclohexanedicarboxylic acid and ruthenium and tin supported thereon. According to the above synthesis method, the selectivity of 1,4-cyclohexane dimethanol finally produced can not be sufficiently secured, or a base may be used in the hydrogenation reaction, which may cause additional processes and costs, and may cause environmental problems There is a problem.

Japanese Laid-Open Publication No. 2002-145824 European Registration No. 0934920 U.S. Patent No. 6294703

The present invention relates to a process for producing 1,4-cyclohexanedimethanol with high purity, while simplifying the reaction process to increase the efficiency and economy of the reaction and minimize the by-products in a shorter time.

Reducing terephthalic acid in the presence of a first metal catalyst comprising a palladium (Pd) compound immobilized on a dealuminated zeolite carrier; And a ruthenium (Ru) compound, a tin (Sn) compound, and a platinum (Pt) compound in a weight ratio of 1: 0.8 to 1.2: 0.2 to 0.6 based on the weight of the metal, fixed to the dealuminated zeolite carrier Reducing the result of the reduction of the terephthalic acid in the presence of a bimetallic catalyst to produce 1,4-cyclohexanedimethanol.

The method for producing 1,4-cyclohexanedimethanol according to a specific embodiment of the present invention will be described in more detail below.

According to one embodiment of the invention, there is provided a process for the production of a zeolite catalyst, comprising: reducing terephthalic acid in the presence of a first metal catalyst comprising a palladium (Pd) compound immobilized on a dealuminated zeolite carrier; And a ruthenium (Ru) compound, a tin (Sn) compound, and a platinum (Pt) compound in a weight ratio of 1: 0.8 to 1.2: 0.2 to 0.6 based on the weight of the metal, fixed to the dealuminated zeolite carrier A process for producing 1,4-cyclohexanedimethanol, comprising reducing the reduction product of terephthalic acid in the presence of a bimetallic catalyst, can be provided.

The inventors of the present invention have conducted research on a method of synthesizing a cycloalkane diol by direct hydrogenation of an aromatic dicarboxylic acid to use a first metal catalyst fixed on a dealuminated zeolite carrier and a second metal catalyst It is possible to reduce the aromatic dicarboxylic acid to a high efficiency without lowering the reaction activity due to long-term use.

Specifically, terephthalic acid is reduced using the first metal catalyst, and then a second metal catalyst containing a ruthenium (Ru) compound, a tin (Sn) compound and a platinum (Pt) When the reduction product is reduced again, terephthalic acid, which is a reactant, can mostly participate in the reaction and realize a high conversion rate, and it is possible to provide 1,4-cyclohexane dimethanol with high purity while minimizing by-products in a shorter time.

In addition, in the manufacturing method of this embodiment, the active component of each of the first metal catalyst and the second metal catalyst is used in a state of being fixed to a dealuminated zeolite carrier, and the active component is added to the dealuminated zeolite carrier It is possible to achieve a result that the selectivity of 1,4-cyclohexanedimethanol is more than 90% in the final product while ensuring a high reaction conversion rate of 99% or more. These effects are attributed to the ratio of the alumina to silica in the dealuminized zeolite carrier, the zeolite carrier, the acidity, and the smooth reaction effect depending on the proper pore size.

Specifically, the zeolite carrier contained in each of the first and second metal catalysts may have a specific surface area of from about 200 to about 900 m 2 / g, or from about 300 to about 800 m 2 / g. If the specific surface area of the zeolite support is too small, the active site between the reactant and the catalyst is reduced and the reaction does not work smoothly or the metal, which plays an important role of the catalyst, can not be supported on the carrier, May occur. In addition, if the specific surface area of the zeolite support is too large, the degree of dispersion of the catalyst metal becomes excessively high, and the reaction may not proceed smoothly.

The total pore volume of the zeolite carrier contained in each of the first metal catalyst and the second metal catalyst may be about 1.2 cm3 / g or less. If the total pore volume of the zeolite carrier contained in each of the first metal catalyst and the second metal catalyst is too large, excessive reactants that are excessively active between the reactants and the catalyst are produced in an excessive amount, The contact efficiency between the reactant and the catalyst is greatly reduced, so that the reaction may not proceed smoothly.

Also, the volume of pores having a radius of 10 A or less in the zeolite carrier contained in each of the first and second metal catalysts may be from about 0.1 to about 0.8 cm3 / g, or from about 0.2 to about 0.7 cm3 / g. have.

In the zeolite carrier included in each of the first metal catalyst and the second metal catalyst, the pores having a radius of 10 Å or less can enhance the activity and enhance the enantioselectivity. If the volume of the pores having a radius of 10 Å or less in the zeolite carrier is too small, the large organic molecules can not be adsorbed in the micropores, so that the pore structure is destroyed by the high temperature treatment at the time of catalyst formation or pressure The internal surface area thereof is rapidly reduced to lose the adsorption property of the substance, and the metal catalyst component may be escaped.

If the volume of the pores having a radius of 10 Å or less in the zeolite carrier is too large, the dispersibility of the metal catalyst is widened, and the reaction rate is accelerated to produce excessive amounts of the byproducts or decrease the selectivity of the enantiomer of the product .

The zeolite carrier contained in each of the first metal catalyst and the second metal catalyst is a dealuminated zeolite, and the dealumination can be performed by acid treatment.

Under the reaction conditions of terephthalic acid, the dealumination of the zeolite itself due to the acidity of the reactants or intermediates proceeds and the aluminum content in the reaction product solution increases. When the increased aluminum is contained in the product 1,4-cyclohexane dimethanol, Can cause problems. For example, 1,4-cyclohexanedimethanol as a product is mainly used as an additive for improving the physical properties of a resin such as polyethylene terephthalate (PET). The aluminum component is not sufficiently removed and 1,4-cyclohexanedimethanol When introduced into a product together with methanol, the physical properties of the resin such as transparency, moisture permeability and the like may be lowered. Further, in the process for producing 1,4-cyclohexane dimethanol, aluminum oxide is generated in a large amount during post-treatment such as separation of high boiling point / high molecular weight components, and aluminum oxide is accumulated in a moving pipe or a filtration device, ≪ / RTI > This is especially true at the beginning of the reaction where the aluminum content of the catalyst is highest and affects the initial reaction setting for long-term operation. On the other hand, according to the present invention, it is possible to prevent the aluminum from flowing into the reaction product by performing the pre-treatment with de-aluminum for the zeolite.

Examples of the acid usable for dealumination include sulfuric acid (H ₂ SO ₄ ), nitric acid (HNO ₃ ), hydrofluoric acid (HF), hydrochloric acid (HCl), bromic acid (HBr) ); Or oxalic acid, formic acid, terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, But are not limited to, 1,3-cyclohexanedicarboxylic acid, benzoic acid, adipic acid, glutaric acid, succinic acid, malonic acid, And organic acids such as maleic acid and the like. Preferably, oxalic acid can be used.

The concentration of the solution used in the acid treatment may be about 0.1 to about 5M, more preferably about 0.5 to about 3M. In addition, the volume of the acid used in the acid treatment may be about 10 to about 30 mL per 1 g of zeolite, but is not limited to the above range and can be used in an excessive amount.

The temperature during the acid treatment is in the range of room temperature to the reflux temperature of the solution, and the time is more than 1 hour.

During the acid treatment under the above conditions, there is no damage in the analytical range of crystallinity of the zeolite, and the dealumination can be reached from about 50% to less than about 90%.

The zeolite carrier contained in each of the first metal catalyst and the second metal catalyst may be a Y-type zeolite. In the production method of this embodiment, the active component of each of the first metal catalyst and the second metal catalyst is fixed to the zeolite carrier, as compared with the case of using a carrier of another kind, for example, activated carbon, The selectivity of 1,4-cyclohexane dimethanol can be ensured, reaction activity can be increased, or thermal, mechanical, and reaction stability effects can be realized during catalyst formation.

On the other hand, according to the process for producing 1,4-cyclohexane dimethanol in one embodiment, by-product is not generated in the course of synthesizing 1,4-cyclohexane dimethanol from terephthalic acid, so that an additional process or step for separating and recovering by- Can be omitted, and the purification process for increasing the purity can be minimized.

In addition, the process for preparing 1,4-cyclohexane dimethanol in one embodiment can provide a relatively simplified reaction process design and can provide a high purity 1,4-cyclohexane dimethanol with a high yield in a shorter time The efficiency and economical efficiency of the entire manufacturing process can be improved.

As described above, in the method for producing 1,4-cyclohexanedimethanol in one embodiment, it may include reducing terephthalic acid in the presence of a first metal catalyst comprising a palladium (Pd) compound. The palladium (Pd) compound means palladium metal itself, an organic salt of palladium or an inorganic salt of palladium.

The benzene ring of terephthalic acid can be reduced through the first metal catalyst comprising the palladium (Pd) compound, thereby forming 1,4-cyclohexane dicarboxylic acid.

The first metal catalyst may comprise about 0.05 to about 10 wt%, or about 0.1 to about 5 wt%, based on the weight of the palladium (Pd) metal, palladium (Pd) compound and the balance zeolite carrier .

In the step of reducing terephthalic acid, various reduction methods may be used. For example, the step of reducing terephthalic acid may include contacting the terephthalic acid and hydrogen gas.

In the step of reducing the terephthalic acid, a method, reaction conditions, and apparatus known to be used in the reduction reaction of an aromatic carboxylic acid can be used without any limitation. For example, the step of reducing terephthalic acid may be performed at a temperature of about 50 to about 350 & Or at a temperature of from about 100 to about 300 DEG C and at a pressure of from about 30 to about 150 bar, or from about 40 to about 100 bar.

Specifically, the step of reducing the terephthalic acid may include introducing a hydrogen gas into the atmosphere of the first metal catalyst containing the palladium (Pd) compound and the reactor in which terephthalic acid is present, into an atmosphere of an inert gas such as nitrogen, Lt; / RTI >

In the step of reducing terephthalic acid, about 10 to about 300 parts by weight, preferably about 50 to about 300 parts by weight, and more preferably about 50 to about 200 parts by weight of the first metal catalyst is added to 100 parts by weight of the terephthalic acid Can be used.

If the content or amount of the first metal catalyst is too low relative to the terephthalic acid, the efficiency of the reduction reaction may be decreased or the selectivity of 1,4-cyclohexanedimethanol may be lowered in the resultant reaction product, The production efficiency of the reaction apparatus is lowered and the efficiency of the apparatus or the energy consumption may become excessive when the final product is obtained and then separated / recovered. If the content or the amount of the first metal catalyst is too high relative to the terephthalic acid, since the by-products are excessively generated in the course of the reaction, it is not economical to perform additional steps in order to remove the by- The purity may be lowered.

The ruthenium (Ru) compound, the tin (Sn) compound, and the platinum (Pt) compound may be prepared by reducing the terephthalic acid obtained by reducing the terephthalic acid in the process for producing 1,4- In the presence of a second metal catalyst comprising the compound in a weight ratio of 1: 0.8 to 1.2: 0.2 to 0.6 based on the weight of the metal.

The ruthenium contained in the second metal catalyst seems to convert the dicarboxylic acid into the primary alcohol. The tin seems to increase the selectivity of the resultant alcohol, and the platinum improves the activity of the catalyst It seems to play a role in suppressing side reactions.

Reduction of the reduction product of terephthalic acid containing 1,4-cyclohexane dicarboxylic acid in the presence of the second metal catalyst may result in the formation of reaction products including 1,4-cyclohexane dimethanol.

Wherein the second metal catalyst comprises a ruthenium (Ru) compound, a tin (Sn) compound and a platinum (Pt) compound in a weight ratio of 1: 0.8 to 1.2: 0.2 to 0.6 or 1: 0.9 to 1.1: 0.3 to 0.55 . At this time, the weight ratio of the ruthenium (Ru) compound, the tin (Sn) compound, and the platinum (Pt) compound (Ruthenium, tin, and platinum) contained in each of them.

As can be seen from the following Examples and the like, by using a second metal catalyst containing ruthenium (Ru) compound, tin (Sn) compound and platinum (Pt) compound in the specified weight ratio, almost all of terephthalic acid used as a reactant Can participate in the reaction to realize a high conversion rate, and the selectivity of 1,4-cyclohexane dimethanol among the final products to be produced can be kept high.

The ruthenium (Ru) compound means the ruthenium metal itself, an organic salt of ruthenium or an inorganic salt of ruthenium. This also applies to tin (Sn) compounds and platinum (Pt) compounds.

The ruthenium (Ru) compound may include about 0.5 to about 20 wt.%, Or about 5 to about 12 wt.% Ruthenium (Ru) metal, based on the total weight of the second metal catalyst. The content of the tin (Sn) compound and the platinum (Pt) compound in the second metal catalyst may be determined as the content of the ruthenium compound (or metal) and the weight ratio between the compound (or metal).

If the content of the ruthenium (Ru) compound, the tin (Sn) compound and the platinum (Pt) compound in the second metal catalyst is too low, the efficiency of the reduction reaction becomes poor, or 1,4- The selectivity of dimethanol may be lowered and the reaction yield may be lowered due to the generation of unreacted carboxylic acid or carboxylic acid anhydride. When the final reaction product is separated or recovered, the efficiency may be lowered or the energy consumption may be excessive have.

If the content of the ruthenium (Ru) compound, the tin (Sn) compound and the platinum (Pt) compound in the second metal catalyst is too high, an additional reaction may occur excessively to form a primary alcohol form, The reaction yield may be lowered or the purity of the final reaction product may be lowered. In order to remove the produced by-products, various steps must be additionally performed, so that the economics of the process may be lowered.

In the step of reducing the reduction product of terephthalic acid, various reduction methods may be used. For example, reducing the reduction product of terephthalic acid may include contacting the reduction product of terephthalic acid with hydrogen gas.

In the step of reducing the reduction product of terephthalic acid, a method, a reaction condition, and an apparatus known to be used for the reduction reaction of an aromatic carboxylic acid can be used without any limit. For example, the step of reducing the reduction product of terephthalic acid At a temperature of from about 50 to about 350 DEG C, or from about 100 to about 300 DEG C, and from about 30 to about 150 bar, or from about 40 to about 100 bar.

Specifically, the step of reducing the reduction product of terephthalic acid may be performed by introducing a hydrogen gas into the atmosphere of the inert gas such as nitrogen during the reduction reaction of the second metal catalyst and the terephthalic acid, Lt; / RTI >

In the step of reducing the reduction product of terephthalic acid, about 10 to about 300 parts by weight, preferably about 50 to about 300 parts by weight, of the second metal catalyst is added to 100 parts by weight of the reduction product of terephthalic acid, 50 to about 200 parts by weight. If the content or the amount of the second metal catalyst is too low relative to the reduction product of terephthalic acid, the efficiency of the reduction reaction may be decreased or the selectivity of 1,4-cyclohexane dimethanol may be lowered If the catalyst content is insufficient, the production efficiency of the reaction apparatus is lowered, and when the final product is obtained and then separated / recovered, the efficiency of the apparatus or energy consumption may become excessive.

If the content or amount of the second metal catalyst is too high as compared with the reduction product of terephthalic acid, the by-products are excessively generated in the course of the reaction. Therefore, it is not economical to perform the various steps in order to remove the by- The purity of the resultant product may be lowered.

Meanwhile, in the above process for producing 1,4-cyclohexane dimethanol, the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid may be performed continuously. This means that 1,4-cyclohexane dimethanol can be formed from terephthalic acid through one process or a reaction process.

The step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid may be performed in one reactor. Means that the reduction of the terephthalic acid and the reduction of the reduction product of terephthalic acid are carried out in the same reactor without being separated in a separate process or transferring the reaction product.

In the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid, the reactants themselves may be directly reduced and the reduction reaction may occur in the presence of the reactants in the solvent.

The examples of the usable solvent are not limited to a great extent. For example, water or an organic solvent may be used. Examples of the organic solvent include aliphatic alcohols such as methanol, ethanol, propanol and cyclohexanol, aliphatic alcohols such as hexane and cyclohexane, Ethers such as hydrocarbons, diethyl ether, and tetrahydrofuran, or a mixture of two or more of them may be used.

The amount of the organic solvent to be used is not limited, and may be, for example, about 10% to 1,000% by weight of the reaction product terephthalic acid and / or the reduction product of terephthalic acid.

In the process for producing 1,4-cyclohexane dimethanol according to one embodiment of the present invention, it is possible to further separate the used catalyst and purify the reaction product at the completion of the respective reduction reaction steps. Although the method which can be used for the purification is not limited to a great degree, it can be separated and purified by distillation, extraction, chromatography and the like.

According to the process for preparing 1,4-cyclohexane dimethanol provided herein, the reactants can participate in almost all the reactions to realize a high conversion rate, and can produce 1,4-cyclohexane dimethanol with a high purity while minimizing the by- Dimethanol. ≪ / RTI > The process for the production of 1,4-cyclohexane dimethanol enables a relatively simplified process design and provides high purity 1,4-cyclohexane dimethanol as a high yield in a shorter time, And economic efficiency can be improved.

In addition, according to the process for producing 1,4-cyclohexane dimethanol, it is possible to omit the additional process or step of separating and recovering the by-products by minimizing the by-products generated in the course of producing 1,4- And the purification process for increasing the purity can be omitted.

The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

EXAMPLES: Direct Conversion of Terephthalic Acid to 1,4-Cyclodicarboxyl Methanol [

In one reactor, terephthalic acid is used as a starting material and directly converted to cyclohexane dimethanol using a mixed catalyst of a Pd catalyst and a Ru-Sn-Pt catalyst.

[Manufacturing Example]

Production Example 1

1-1. Dealumination of zeolite

100 g of Y-zeolite [specific surface area: about 600 m 2 / g, total pore volume of 1.0 cm 3 / g, pore volume having a radius of 10 Å or less, about 0.5 cm 3 / g] was put into a 2 liter oxalic acid aqueous solution The mixture was stirred while being heated to an internal temperature of 90 DEG C and refluxed for 6 hours. Thereafter, the excess acid was filtered out by filtration under reduced pressure, followed by washing / filtration with hot water at 70 占 폚 or more. The filtered dealuminated zeolite was dried at 120 ° C. for 12 hours and then calcined at 500 ° C. for 4 hours in a firing machine.

1-2. Preparation of first metal catalyst and second metal catalyst

The catalyst was prepared using a general incipient wetness process.

Specifically, palladium chloride was dissolved in ion-exchanged water to prepare a first metal catalyst, and this solution was dropped one by one into an evaporation plate containing the zeolite of Production Example 1-1. When the solution was cooled in the zeolite pores, water was evaporated off and a residue was obtained. The obtained residue was dried under reduced pressure and then calcined at atmospheric conditions and at a temperature of 550 DEG C for 3 hours to obtain a first metal catalyst containing palladium-supported dealuminated Y-zeolite.

To prepare the second metal catalyst, specifically, ruthenium chloride trihydrate is dissolved in ion-exchanged water, and this solution is dropped one by one into an evaporation plate containing the zeolite of Production Example 1-1. When the solution in the pores was cooled, the water was evaporated off and the residue was obtained. The process carried out using the ruthenium chloride trihydrate was repeated with tin chloride dihydrate and chloroplatinic acid, respectively.

The obtained residue was dried under reduced pressure and then calcined at atmospheric conditions and at a temperature of 550 DEG C for 3 hours to obtain Ru (Ru), Sn (Sn) and Pt (Pt) supported on dealuminated Y- A second metal catalyst was prepared. The ratios of ruthenium (Ru), tin (Sn) and platinum (Pt) are as shown in Table 1 below.

Production Example 2: Preparation of metal catalyst

Zeolite obtained in Preparation Example 1-1 was used as a carrier except that activated carbon was used for the calcination treatment at a temperature of 200 ° C for 3 hours instead of the dealuminated Y- A metal catalyst was prepared.

Production Example 3: Preparation of metal catalyst

The first and second metal catalysts were prepared in the same manner as in Preparation Example 2 except that ruthenium (Ru), tin (Sn), and platinum (Pt) The ratios of ruthenium (Ru), tin (Sn) and platinum (Pt) are as shown in Table 1 below.

Production Example 4: Preparation of metal catalyst

The first and second metal catalysts were prepared in the same manner as in Preparation Example 2 except that ruthenium (Ru), tin (Sn), and platinum (Pt) The ratios of ruthenium (Ru), tin (Sn) and platinum (Pt) are as shown in Table 1 below.

Production Example 5: Preparation of metal catalyst

The first and second metal catalysts were prepared in the same manner as in Preparation Example 1, except that ZSM-5 zeolite was used as a carrier instead of the dealuminated Y-zeolite of Preparation Example 1-1.

Preparation Example 6: Preparation of metal catalyst

The procedure of Production Example 1 was repeated except that Fumed Silic [specific surface area: 475 m ² / g, average particle size 4.5 μm] was used as a carrier instead of the dealuminated Y-zeolite of Production Example 1-1. And a second metal catalyst.

The compositions of the catalysts prepared in Preparation Examples 1 to 6 are summarized in Table 1 below.

division The first metal catalyst The second metal catalyst Furtherance The amount of metal supported (wt% of the metal with respect to the weight of the supported catalyst) Furtherance The amount of metal supported (wt% of the metal with respect to the weight of the supported catalyst) Production Example 1 Pd /
Y-Zeolite (de-Al) 2.5 Ru-Sn-Pt
/ Y-Zeolite (de-Al) 2.5: 2.5: 1.5 Production Example 2 Pd / C 2.5 Ru-Sn-Pt / C 2.5: 2.5: 1.5 Production Example 3 Pd / C 5 Ru-Sn-Pt / C 5: 5: 2 Production Example 4 Pd / C One Ru-Sn-Pt / C 1: 1: 0.5 Production Example 5 Pd / ZSM-5 2.5 Ru-Sn-Pt / ZSM-5 2.5: 2.5: 1.5 Production Example 6 Pd / SiO ₂ 2.5 Ru-Sn-Pt / SiO ₂ 2.5: 2.5: 1.5

[ Example  And Comparative Example : 1,4- Of cyclohexanedimethanol  Produce]

Example 1

A 300 mL high-pressure reactor equipped with a stirrer was charged with 10.0 g of the first metal catalyst obtained in Preparation Example 1, 10.0 g of terephthalic acid, and 100 g of ion-exchanged water. After the atmosphere in the high-pressure reactor was replaced with nitrogen at room temperature, hydrogen gas was introduced into the high-pressure reactor at a rate of 28 kg / cm < 2 > At this time, the stirring speed in the high-pressure reactor was fixed at 450 rpm, and the reaction was continued until there was no change in internal pressure.

After cooling the inside of the reactor to room temperature with no change in internal pressure of the high-pressure reactor, 10.0 g of the second metal catalyst obtained in Preparation Example 1 was added and the atmosphere in the reactor was replaced with nitrogen.

Then, hydrogen gas was injected into the reactor at a rate of 54 kg / cm < 2 >, and the internal temperature of the high-pressure reactor was increased to 230 DEG C to carry out the hydrogenation reaction. The stirring speed in the high-pressure reactor was fixed at 450 rpm and the reaction was continued until there was no change in internal pressure. When the inside pressure of the high-pressure reactor was no longer changed, the interior of the reactor was cooled to 70 ° C, the reactor was disassembled, and the reaction product was collected. The reaction product was distilled off at 50 캜 using a concentrated rotary evaporator to obtain the final product (1,4-cyclohexane dimethanol).

Comparative Example 1

1,4-cyclohexanedimethanol was prepared in the same manner as in Example 1, except that the first and second metal catalysts obtained in Preparation Example 2 were used.

Comparative Example 2

1,4-cyclohexanedimethanol was prepared in the same manner as in Example 1, except that the first and second metal catalysts obtained in Preparation Example 3 were used.

Comparative Example 3

1,4-cyclohexanedimethanol was prepared in the same manner as in Example 1, except that the first and second metal catalysts obtained in Preparation Example 4 were used.

Comparative Example  4

Cyclohexane dimethanol was prepared in the same manner as in Comparative Example 2, and the first and second metal catalysts used were evaporated to dryness, and the same procedure was repeated to produce 1,4-cyclohexane dimethanol.

Comparative Example 5

1,4-cyclohexanedimethanol was prepared in the same manner as in Example 1, except that the first and second metal catalysts obtained in Preparation Example 5 were used.

Comparative Example 6

1,4-cyclohexanedimethanol was prepared in the same manner as in Example 1, except that the first and second metal catalysts obtained in Preparation Example 6 were used.

[Experimental Example]

1. Conversion of terephthalic acid and selectivity of 1,4-cyclohexanedimethanol

The conversion of the reaction material (terephthalic acid) and the selectivity of 1,4-cyclohexanedimethanol were measured by gas chromatography (GC) on the final products obtained in Example 1 and Comparative Examples 1 to 6, .

Specifically, the reaction product obtained by the reduction reaction (hydrogenation reaction) of the reaction material (terephthalic acid) was diluted with methanol so that the concentration of cyclohexane dimethanol was about 1% by weight. The selectivity of cyclohexane dimethanol was calculated by gas chromatography (GC) analysis of the diluted solution. The respective values were converted into molar ratios (%), and then [(cyclohexane dimethanol / product) * 100 ].

In the case of terephthalic acid, the conversion and selectivity of terephthalic acid remained after the reaction due to poor solubility in water and the remaining filtrate after catalyst filtration were calculated.

※ Gas Chromatography (GC) conditions

1) Column: Agilent 19091J-413 (column length: 30 m inner diameter: 0.32 mm film thickness: 0.25 m)

2) GC apparatus: gas chromatography model Agilent 7890

3) Carrier gas: helium

4) Detector: Flame ionization detector (FID)

Terephthalic acid conversion rate
(unit: %) Selectivity of 1,4-cyclohexanedimethanol
(unit: %) Example 1 100 93 Comparative Example 1 100 78 Comparative Example 2 100 65 Comparative Example 3 100 43 Comparative Example 4 100 One time -78
2 times - 61
3 times -55
4 times -51
5 times -42
6 times -32 Comparative Example 5 75 30 Comparative Example 6 96 52

As shown in Table 2, in Example 1, it was confirmed that the reaction product, terphthalic acid, was 100% converted and the selectivity of 1,4-cyclohexane dimethanol was 90 or more in the resulting product. On the contrary, in Comparative Examples 1 to 6, the selectivity was significantly lowered, and it was confirmed that the final product was also produced by-products other than 1,4-cyclohexane dimethanol.

2. Aluminum content analysis

The aluminum content in the first and second metal catalysts before and after the reaction of Example 1 and the aluminum content in the final product after the reaction were analyzed using an ICP-MS (inductively coupled plasma mass spectrometer).

As a result, the aluminum content in the first and second metal catalysts before the reaction was 0.34 wt%, the aluminum content in the first and second metal catalysts after the reaction was 0.28 wt%, and the aluminum content in the final product after the reaction was 9.5 ppm , It was confirmed that when the catalyst prepared using the dealuminated zeolite as a carrier was used, the residual aluminum content in the product was less than 10 ppm.

Claims (15)

Dealluminating the zeolite carrier using an organic acid;
Reducing terephthalic acid in the presence of a first metal catalyst comprising a palladium (Pd) compound immobilized on a dealuminated zeolite carrier; And
(2) containing a ruthenium (Ru) compound, a tin (Sn) compound and a platinum (Pt) compound in a weight ratio of 1: 0.8 to 1.2: 0.2 to 0.6, based on the weight of the metal, fixed on the dealuminated zeolite carrier Reducing the reduction product of terephthalic acid in the presence of a metal catalyst;
Lt; / RTI >
Wherein a total pore volume of the zeolite carrier contained in each of the first metal catalyst and the second metal catalyst is 1.2 cm3 / g or less and a volume of pores having a radius of 10 Å or less is 0.1 cm3 / g to 0.8 cm3 / g,
A process for the production of 1,4-cyclohexanedimethanol.
delete The method according to claim 1,
Wherein the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid are carried out continuously.
The method according to claim 1,
Wherein the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid are carried out in one reactor.
The method according to claim 1,
Wherein the dealuminated zeolite carrier contained in each of said first metal catalyst and said second metal catalyst has a specific surface area of from 200 to 900 m < 2 > / g,
A process for the production of 1,4-cyclohexanedimethanol.
delete The method according to claim 1,
Wherein the dealuminated zeolite carrier contained in each of the first metal catalyst and the second metal catalyst is a Y-type zeolite.
The method according to claim 1,
Wherein the first metal catalyst comprises the palladium (Pd) compound in an amount of 0.5 to 10 wt% based on the weight of the palladium (Pd) metal.
The method according to claim 1,
Wherein the second metal catalyst comprises the ruthenium (Ru) compound in an amount of 0.5 to 20 wt% based on the weight of the ruthenium (Ru) metal.
The method according to claim 1,
Wherein reducing the terephthalic acid comprises contacting the terephthalic acid and hydrogen gas,
Wherein reducing the reduction product of terephthalic acid comprises contacting reduction product of terephthalic acid with hydrogen gas.
The method according to claim 1,
Wherein the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid are carried out at a temperature of 50 to 350 ° C, respectively.
The method according to claim 1,
Wherein the step of reducing the terephthalic acid and the step of reducing the reduction product of terephthalic acid are each performed at a pressure of 30 to 150 bar.
The method according to claim 1,
Wherein 10 to 300 parts by weight of the first metal catalyst is used relative to 100 parts by weight of the terephthalic acid.
The method according to claim 1,
Wherein 10 to 300 parts by weight of the second metal catalyst is used relative to 100 parts by weight of the reduction product of terephthalic acid.
The method according to claim 1,
Wherein the second metal catalyst comprises a ruthenium (Ru) compound, a tin (Sn) compound and a platinum (Pt) compound in a weight ratio of 1: 0.9 to 1.1: 0.3 to 0.55, ≪ / RTI >