KR20160143620A - Method for hydrogenation of phthalate compound - Google Patents

Abstract

The present invention relates to a process for the hydrogenation of phthalate compounds. According to the hydrogenation method of the present invention, the entire catalyst life can be increased by separately operating the zones having different catalytic activities during the hydrogenation reaction of the phthalate compound. Therefore, the cost of maintenance and repair of the process is reduced, the stability of the process is improved, and the productivity can be improved.

Description

[0001] METHOD FOR HYDROGENATION OF PHTHALATE COMPOUND [0002]

The present invention relates to a process for the hydrogenation of phthalate compounds. More particularly, the present invention relates to a method for hydrogenating a phthalate compound, which can improve the lifetime of the catalyst as a whole by dividing the reactor into multiple stages according to the degree of catalyst deactivation.

Phthalate-based compounds are widely used as plastics, especially as plasticizers for polyvinyl chloride (PVC). For example, electric and electronic products, medicines, paint pigments, lubricants, binders, surfactants, adhesives, tiles, food containers, packaging materials and the like.

However, as several phthalate compounds are known to cause environmental pollution and problems with endocrine disruption in humans, efforts to reduce their use have been strengthened in advanced countries such as Europe and the United States. Some products such as di (2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP) and di-n-butyl phthalate (DBP) among the phthalate plasticizers have socially an endocrine system As endocrine disrupters, environmental hormones are suspected and there is a movement to regulate them.

Accordingly, efforts have been made to develop environmentally friendly plasticizers that exhibit conventional performance and are free from environmental hormone controversy. One of them is a method of using a hydrogenation compound which is a benzene ring contained in a phthalate compound.

A hydrogenation reaction of an aromatic compound such as a benzene ring is known to use a catalyst containing a transition metal such as ruthenium as an active component in a support.

However, since the catalytic activity of the transition metal is drastically reduced as the reaction progresses, the yield is lowered. Therefore, maintenance of catalytic activity is a very important problem in terms of commercial activity. Reduction of the catalytic activity is caused by various physical and chemical influences on the catalyst, such as blockage of catalytically active sites or loss of catalytically active sites as a result of thermal, mechanical or chemical treatment. For example, catalyst deactivation or aging is generally caused by sintering of the catalytically active sites, loss of metal as a result of deposits, or poisoning of the active sites, and a variety of mechanisms exist. Such replacement and regeneration processes due to reduced activity of the catalyst lead to product production costs.

Accordingly, in order to produce a substance usable as an environmentally friendly plasticizer on a commercial scale, there is a demand for improving the performance of the catalyst used in the hydrogenation reaction and maintaining the activity thereof, thereby increasing the life time of the catalyst.

In order to solve the above problems, it is an object of the present invention to provide a hydrogenation method for promoting the lifetime of a catalyst in a hydrogenation process of a phthalate compound, thereby reducing costs and securing stability of operation.

Thus, according to one embodiment of the present invention,

Introducing a phthalate compound and hydrogen into a first-stage reactor filled with a hydrogenation catalyst to react;

Introducing a reaction product discharged from the first-stage reactor into a second-stage reactor connected to the first-stage reactor and filled with a hydrogenation catalyst, and reacting; And

And independently replacing the hydrogenation catalysts of the first and second stages of the reactor according to the degree of deactivation of the hydrogenation catalyst packed in the first and second stages of the reactor, respectively.

According to the hydrogenation process of the present invention, the entire catalytic life can be increased by separately operating the zones having different catalytic activities during the hydrogenation reaction of the phthalate compounds. Therefore, the cost of maintenance and repair of the process is reduced, the stability of the process is improved, and the productivity can be improved.

FIG. 1 is a graph showing changes in catalytic activity with time in Examples 1 to 3 and Comparative Example 1. FIG.
2 is a flowchart of a hydrogenation process according to an embodiment of the present invention.
3 is a diagram illustrating a hydrogenation apparatus according to an embodiment of the present invention.
4 is a view showing a hydrogenation apparatus according to another embodiment of the present invention.

The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated and described in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Hereinafter, a method of hydrogenating a phthalate compound of the present invention will be described in detail with reference to the drawings.

According to an embodiment of the present invention, there is provided a hydrogenation method comprising the steps of: charging a first stage reactor filled with a hydrogenation catalyst with a phthalate compound and hydrogen; Introducing a reaction product discharged from the first-stage reactor into a second-stage reactor connected to the first-stage reactor and filled with a hydrogenation catalyst, and reacting; And independently replacing the hydrogenation catalysts of the first and second stages of the reactor according to the degree of deactivation of the hydrogenation catalyst packed in the first and second reactor.

The reaction object of the hydrogenation process of the present invention is a phthalate compound, and hydrogen is added to the benzene ring of the phthalate compound by hydrogenation to convert it into the corresponding cyclohexane dicarboxylate compound.

The phthalate compound may be at least one selected from the group consisting of phthalate, terephthalate, isophthalate and the corresponding carboxylic acid. Specific examples of the phthalate compound include dibutyl phthalate (DBP), dihexyl phthalate (DHP), dioctyl phthalate (DOP), di-n-octyl phthalate (DnOP) phthalate compounds (di-R1 phthalate, R1 is a straight chain or branched alkyl group having 1 to 20 carbon atoms) such as octyl phthalate, diisononyl phthalate, or diisodecyl phthalate (DIDP); Such as dibutyl terephthalate (DBTP), dioctyl terephthalate (DOTP), diisononyl terephthalate (DINTP), or diisodecyl terephthalate (DIDTP) R2 is a straight chain or branched alkyl group having 1 to 20 carbon atoms, dibutyl isophthalalate (DBIP), dioctyl isophthalate (DOIP), diisononyl isophthalate (DINIP isophthalate compounds (di-R3 isophthalate, R3 is a straight or branched alkyl group having 1 to 20 carbon atoms) such as diisononyl isophthalate or diisodecyl isophthalate (DIDIP) The compounds may be used alone or in combination.

Preferably, it may be dioctyl terephthalate (DOTP).

The hydrogenation catalyst may contain a transition metal of Group 8 as an active component and is preferably one selected from the group consisting of ruthenium (Ru), nickel (Ni), palladium (Pd), rhodium (Rh) Or more.

By this hydrogenation reaction, the aromatic ring of the phthalate compound is hydrogenated and converted into the corresponding cyclohexanedicarboxylate compound.

Throughout the specification of the present invention, the term "reaction zone" means a region having physically independent regions and satisfying the conditions under which the hydrogenation reaction of the phthalate compound can occur, (N is an integer of 1 or more) of the first, second, and third steps of separating the reaction zone, Refers to a reaction step that is sequentially connected in accordance with the flow of hydrogenation reaction of the phthalate compound and can be divided in series. For example, the second-step reaction zone is connected in series with the first- And the third step reaction region is a reaction region connected in series with the previous second step reaction region.

The reactor used in the conventional hydrogenation process is a tube type reactor, and a solid hydrogenation catalyst is packed inside a tube type reactor. The reaction raw material containing the phthalate compound and hydrogen flows into the upper portion of the reactor to form a flow flow, and the hydrogenation reaction proceeds under the hydrogenation catalyst packed in the reactor, and the reaction product is discharged to the lower portion of the reactor.

However, as the reaction progresses, the activity of the catalyst decreases due to the impurities present in the reaction material. The reduction in catalytic activity is due to the various physical and chemical influences on the catalyst and is caused, for example, by the blockage of catalytically active sites or the loss of catalytically active sites as a result of thermal, mechanical or chemical treatments. Also, in the early stage of the reaction, the reaction proceeds rapidly due to the reaction raw material at a high concentration, and the reaction heat is partially accumulated to generate hot spots. As the sintering occurs by the hot spot, the deactivation of the catalyst is further accelerated. Such a decrease in catalytic activity leads to a decrease in the overall reactivity and causes a decrease in the conversion and purity of the reaction product.

However, according to the hydrogenation method of the present invention, the hydrogenation reaction proceeds in multiple steps by dividing the independent reaction regions filled with the respective hydrogenation catalysts into a plurality of regions. That is, the phthalate compound and hydrogen are added to react in the first-step reaction zone, and the reaction product in the first-step reaction zone is reacted in the second-step reaction zone. In the following third-step reaction zone, the reaction product in the second reaction zone is introduced and reacted, and the reaction product in the previous reaction zone is introduced to progress the hydrogenation reaction in multiple stages. The hydrogenation catalyst may be separately packed in the reaction zone, and hydrogenation catalysts of the same kind may be filled.

As described above, in the early stage of the hydrogenation reaction, hot spots are apt to occur, which is a phenomenon in which the reaction proceeds sharply as the reaction progresses in a state where the reaction raw material is in a high concentration and the reaction heat is partially accumulated. This hot spot accelerates the deactivation of the catalyst. Such a decrease in catalytic activity leads to a decrease in the overall reactivity and causes a decrease in the conversion and purity of the reaction product. Therefore, in order to maintain the catalytic activity at a constant level in accordance with the progress of the hydrogenation reaction, it is indispensable to replace or regenerate the catalyst whose activity has decreased.

However, since the reaction raw material forms a flow flow in the upper part of the reactor or the raw material inlet to the lower part or the reaction product outlet side, the hydrogenation reaction proceeds, so that the catalyst on the entire reactor surface is aged quickly in one reactor, Activity remains. Despite the difference in catalyst aging speed, since the catalysts packed in one reactor are in an integrated state, the entire catalyst must be replaced or regenerated, leading to an increase in replacement cost and a decrease in productivity.

However, according to the hydrogenation method of the present invention, the hydrogenation reaction is divided into a plurality of reaction zones, and the efficiency of the hydrogenation reaction can be increased by changing the catalyst replacement cycle according to the degree of decrease in catalytic activity. The reaction zone may be divided into a first stage reaction zone in which an initial hydrogenation reaction is performed by charging a phthalate compound and hydrogen, and a second reaction zone in which a hydrogenation reaction is performed by injecting a reaction product in a previous reaction zone.

When the hydrogenation reaction is performed by dividing the first-step reaction zone independently from the subsequent reaction zone, the catalyst can be independently replaced according to the degree of reduction in catalytic activity in the reaction zone in each step. The activity of the first-step reaction zone is lower than that of the first-stage reaction zone because the lowering of the catalytic activity of the first-step reaction zone, in which the reaction is proceeded, The catalyst in the reaction zone after the second step is sufficiently usable. Therefore, it is only necessary to replace the catalyst in the first-step reaction zone in which the activity is decreased. Thus, it is possible to improve the inefficiency of replacing the catalyst after the second-stage reaction zone in which the activity is still sufficient.

Therefore, according to the production method of the present invention, it is possible to use the catalyst packed in each reaction zone evenly and thereby improve the overall catalyst life.

The number of reaction regions is not particularly limited to two or more, and according to one embodiment of the present invention, the reaction regions can be divided into two. That is, the hydrogenation reaction may be carried out in two steps of charging the phthalate compound and hydrogen in the first-step reaction zone and reacting the reaction product, and then introducing the reaction product in the first- .

Also, according to an embodiment of the present invention, the reaction regions belonging to the same step may be divided into a plurality of groups in parallel, and the reactions may be independently performed, and the plurality of reaction zones divided in parallel may all be operated simultaneously Alternatively, the vehicle can be selectively operated by a switch operation. Thus, when the reaction zones are divided into a plurality of reaction zones, it is possible to continuously operate the reaction zones belonging to the same reaction zone even when the catalyst needs to be replaced in one reaction zone.

2 is a flow chart illustrating a hydrogenation process according to one embodiment of the present invention.

Referring to FIG. 2, first, the raw phthalate compound and hydrogen are introduced into a first-step reaction zone (step S10).

According to an embodiment of the present invention, the phthalate compound may be pressurized and heated to be introduced into the first-step reaction zone.

More specifically, the step of raising and raising the phthalate compound may be carried out simultaneously or sequentially, and the desired pressure and temperature may be reached by increasing the pressure and increasing the temperature several times in one or more steps. For example, the pressure of the phthalate compound may be increased first, and the pressure of the phthalate compound may be elevated to flow into the first-step reaction region in a liquid state having an appropriate viscosity. According to one embodiment of the present invention, the viscosity of the phthalate compound may range from about 0.5 to about 20.0 cps in the range of pressure and temperature conditions when entering the first-step reaction zone. When the viscosity of the phthalate compound is within the above range, it can exhibit proper flowability and reactivity in the reaction zone. The phthalate compound may be added in an appropriate organic solvent in a dissolved state.

The target pressure to be boosted to enter the first stage reaction zone may be from about 50 to about 500 bar, preferably from about 100 to about 300 bar. If the pressure is less than 50 bar, the reactivity is lowered, and it is difficult to obtain a desired level of conversion. If the pressure is excessively higher than 500 bar, the reactor may be difficult to manufacture or the manufacturing cost may be greatly increased.

In addition, the target temperature for raising the temperature to be introduced into the first-stage reaction zone may be in the range of about 50 to about 500 캜, preferably about 100 to about 300 캜. If the temperature is less than 50 캜, the catalyst is inactivated due to the low temperature, the flow of the mixture in the reactor becomes poor due to the high viscosity of the mixture, the hydrogen permeability to the phthalate compound in the liquid phase is lowered, Is excessively higher than 500 ° C, decomposition of the reaction product occurs to a large extent, which makes it difficult to produce a reactor, and rapid reaction may lead to difficulty in heat removal.

The phthalate compound which has been raised and raised by the above-mentioned process is introduced into the first-step reaction region filled with the hydrogenation catalyst.

In addition, hydrogen (H ₂ ) in gaseous state flows into the reaction region through a separate feed line, and the hydrogenation reaction is performed. At this time, the pressure and temperature conditions of hydrogen are the same as the temperature and pressure conditions of the phthalate compound, at a pressure of about 50 to about 500 bar, preferably about 100 to about 300 bar, and a pressure of about 50 to about 500 deg. Lt; RTI ID = 0.0 > 300 C < / RTI >

Next, hydrogenation of the phthalate compound is carried out in the presence of a hydrogenation catalyst in a first-step reaction zone where the phthalate compound and hydrogen are introduced (step S20).

The temperature and pressure conditions in the first stage reaction zone are selected from a temperature of from about 50 to about 500 bar, preferably from about 100 to about 300 bar and a temperature of from about 50 to about 500 캜, preferably from about 100 to about 300 캜 Range. ≪ / RTI >

According to an embodiment of the present invention, the first-step reaction region is divided into a plurality of parallel regions, such as the first-step reaction region and the first-second-step reaction region, . The plurality of first-step reaction zones may be operated simultaneously or alternately in a manner of alternately operating. When the first-stage reaction zone is divided into a plurality of zones, it is advantageous to continuously operate in the first zone of the first-stage reaction zone even when catalyst replacement is required in the first-stage reaction zone.

The hydrogenation process of the present invention can be carried out in a liquid phase or a gas phase. According to an embodiment of the present invention, the phthalate compound may be in a liquid state, and hydrogen may be hydrogenated in a gaseous state.

The phthalate compound is converted into the corresponding cyclohexanedicarboxylate compound in the presence of a hydrogenation catalyst.

According to an embodiment of the present invention, in the first-step reaction region, hydrogenation is carried out until the reaction conversion rate of the initially introduced phthalate compound reaches about 40% to about 95%, preferably about 60% to about 90% Reaction can be carried out. As described above, by controlling the reaction conversion ratio in the first-step reaction region, the final hydrogenation conversion and the catalytic activity efficiency can be further enhanced.

Throughout the specification of the present invention, the term "reaction conversion ratio" means the ratio (percentage) of the number of moles of the phthalate hydrogenated compound produced by the hydrogenation reaction to the number of moles of the phthalate compound charged into the reactor or reaction zone, do.

[Formula 1]

Next, the reaction products in the first-step reaction zone are continuously introduced into the second-step reaction zone (step S30).

The reaction products in the first-step reaction zone include not only hydrogenated compounds of phthalate compounds but also phthalate compounds in an unreacted raw material and hydrogen.

In the second-step reaction zone in which the reaction product is introduced in the first-step reaction zone, the hydrogenation reaction proceeds on the unreacted raw material contained in the reaction product in the presence of the hydrogenation catalyst (Step S40).

The unreacted phthalate compound contained in the reaction product is converted to the corresponding cyclohexanedicarboxylate compound by reaction in the second-step reaction zone. Since the hydrogenation catalyst is packed in the second-step reaction region separately from the first-step reaction region, the hydrogenation reaction can still proceed at a high conversion rate to the unreacted phthalate compound.

The temperature and pressure conditions in the second-stage reaction zone are the same as in the first-stage reaction zone, at a pressure of about 50 to about 500 bar, preferably about 100 to about 300 bar, and about 50 to about 500 ° C, Lt; RTI ID = 0.0 > 300 C < / RTI >

Although only the second-step reaction region is shown in the flow chart of FIG. 2, the third-step reaction region, the fourth-step reaction region, and the like may be continuously provided after the second-step reaction region, if necessary. The hydrogenation catalyst is separately charged into the reaction zone after the addition, and the reaction product of the previous step is transferred to proceed the hydrogenation reaction to the unreacted phthalate compound.

After the hydrogenation is completed, the liquid hydrogenation product and the unreacted gaseous raw material are separated and purified from the reaction product (step S50). The separated gaseous feed can be recycled to the hydrogenation process. The recovered hydrogenation product can be finally separated by decompression and cooling.

According to another embodiment of the present invention, a phthalate compound supply unit; A hydrogen supply unit; A first stage reactor connected to the phthalate compound supply unit and the hydrogen supply unit and filled with a hydrogenation catalyst; And a hydrogenation unit for the phthalate compound, which is connected to the first-stage reactor and includes at least one independent reactor packed with hydrogenation catalysts.

The reactor used in the hydrogenation apparatus of the present invention is a tube type reactor, and a solid hydrogenation catalyst is packed inside a reactor in the form of a tube.

In the hydrogenation apparatus of the present invention, a plurality of independent reactors filled with hydrogenation catalysts are divided into a plurality of stages, and the hydrogenation reaction proceeds in multiple stages in each reactor. That is, in the first-stage reactor, the phthalate compound and hydrogen are introduced from the phthalate compound supply unit and the hydrogen supply unit to react. The second stage reactor is connected to the first stage reactor and reacts with the reaction product discharged from the first stage reactor. The following third-stage reactor is connected to the second-stage reactor, and the reaction product in the second-stage reactor is charged and reacted, so that the reaction product in the previous reactor is charged to proceed the hydrogenation reaction in multiple stages . The hydrogenation catalysts are separately packed in the reactors, and hydrogenation catalysts of the same kind can be filled.

The hydrogenation catalyst may contain a transition metal of Group 8 as an active component and is preferably one selected from the group consisting of ruthenium (Ru), nickel (Ni), palladium (Pd), rhodium (Rh) Or more.

As described above, according to the hydrogenation apparatus of the present invention, since the reactor is provided in a multistage manner and the hydrogenation reaction proceeds stepwise, the efficiency of the catalyst can be increased by changing the catalyst replacement cycle according to the degree of decrease in catalytic activity.

For example, the upper zone in which the catalyst activity is lowered is divided to separate the first stage reactor from the lower reactor, so that the catalyst can be independently replaced in each reactor. Since the first-stage reactor in which the reaction material is injected at a high concentration to form a flow in the downward direction and the reaction proceeds is faster than the catalyst activity drop in the subsequent reactor, the activity in the first- The catalyst in the reactor after the second stage is fully usable. Therefore, only the catalyst of the first-stage reactor with reduced activity can be replaced, thereby improving the inefficiency of replacing the catalyst after the second-stage reactor with sufficient activity.

Through the present invention, the catalyst packed in the reactor can be used satisfactorily and thereby the overall catalyst life can be improved.

According to an embodiment of the present invention, the hydrogenation apparatus further comprises a first stage reactor connected to the phthalate compound supply unit and the hydrogen supply unit, the first stage reactor being filled with a hydrogenation catalyst, and the second stage reactor connected to the first stage reactor, Stage reactor including a second-stage reactor.

As described in the method for hydrogenating the phthalate compound, the conversion rate of the phthalate compound in the first-step reactor may have a conversion of about 40% to about 95%, preferably about 60% to about 90%. By controlling the reaction conversion ratio in the first-stage reactor to the above range, the lifetime of the entire catalyst can be improved.

The phthalate compound supply unit and the hydrogen supply unit may be independently connected to each of the first-stage reactors, which are provided in parallel in a plurality of the first-stage reactors. The plurality of first-stage reactors grouped in parallel may be selectively operated in a manner that they all operate at the same time or alternately switch. When the first-stage reactor is divided into a plurality of the first-stage reactors, it is advantageous that the first-stage reactor can be continuously operated even when the first-stage reactor needs to be replaced.

3 is a diagram illustrating a hydrogenation apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the hydrogenation apparatus 100 of the present invention includes a phthalate compound supply unit 10; A hydrogen supply unit 20; A first stage reactor 30 connected to the phthalate compound supply unit 10 and the hydrogen supply unit 20 and filled with a hydrogenation catalyst; And a second stage reactor 40 connected to the first stage reactor 30 and filled with a hydrogenation catalyst.

The phthalate compound as a raw material is supplied to the first-stage reactor 30 through the phthalate compound supplying unit 10. The phthalate compound may be heated and elevated to be supplied to the first stage reactor 30 at an appropriate temperature and pressure.

Separately, hydrogen is also heated and boosted from the hydrogen supply unit 20 and supplied to the first-stage reactor 30. According to an embodiment of the present invention, the phthalate compound may be in a liquid state, and the hydrogen may be supplied in a gaseous state.

In the first-stage reactor 30, the hydrogenation reaction in which the phthalate compound and hydrogen react with each other and converts to the corresponding cyclohexanedicarboxylate compound proceeds in the presence of the hydrogenation catalyst packed therein. The hydrogenation catalyst may contain a transition metal of Group 8 as an active component and is preferably one selected from the group consisting of ruthenium (Ru), nickel (Ni), palladium (Pd), rhodium (Rh) Or more. The first stage reactor 30 can be adjusted to a pressure of about 50 to about 500 bar and a temperature of about 50 to about 500 < 0 > C.

However, in the first-stage reactor 30, the reaction proceeds rapidly due to the reaction material of high concentration, and the deactivation of the catalyst rapidly occurs due to the accumulation of the reaction heat. Such a decrease in catalytic activity leads to a decrease in the overall reactivity and causes a decrease in the conversion and purity of the reaction product. Therefore, the replacement cycle of the catalyst in the first-stage reactor 30 is faster than that in the second and subsequent stages, and the catalyst can be independently replaced or regenerated according to the replacement cycle of the different catalysts, Lt; / RTI >

The length of the first stage reactor 30 may range from about 10 to about 50%, preferably from about 20 to about 35% of the total length of the reactor combined with the first stage and second stage reactors. By adjusting the length of the first-stage reactor 30 to the above range, substantially no unreacted phthalate-based compounds may remain after the completion of the first and second-stage reactions.

The reaction product discharged from the first-stage reactor 30 is transferred to the second-stage reactor 40, and the hydrogenation reaction proceeds in the second-stage reactor 40 in which the hydrogenation catalyst is independently charged. The reaction product includes not only the hydrogenation product of the phthalate compound but also the unreacted raw material phthalate compound and hydrogen, and the unreacted raw material proceeds to the hydrogenation reaction again in the second-stage reactor 40. The second stage reactor 40 is also filled with a hydrogenation catalyst. The hydrogenation catalyst is a transition metal of Group 8, preferably ruthenium Ru, nickel Ni, palladium (Pd), rhodium (Rh) , Platinum (Pt), and the like.

The final reaction product from the second-stage reactor 40 may be separated and purified through a separation device 50 to be separated into a liquid reaction product and a gaseous unreacted product, and the impurities may be removed to obtain a final reaction product have.

4 is a view showing a hydrogenation apparatus according to another embodiment of the present invention.

Referring to FIG. 4, the hydrogenation apparatus 200 of the present invention includes a phthalate compound supply unit 110; A hydrogen supply unit 120; A first stage reactor (130, 140) connected to the phthalate compound supply part (110) and the hydrogen supply part (120) and filled with a hydrogenation catalyst; And a second stage reactor 150 connected to the first stage reactor 130, 140 and filled with a hydrogenation catalyst.

The phthalate compound as a raw material is supplied to the first-stage reactor (130, 140) through the phthalate compound supplying unit (110). The phthalate compound may be supplied to the first-stage reactor (130, 140) at an elevated temperature and pressure, and at a suitable temperature and pressure.

Separately, hydrogen is also heated and boosted from the hydrogen supply unit 120 and supplied to the first-stage reactor 130, 140. According to an embodiment of the present invention, the phthalate compound may be in a liquid state, and the hydrogen may be supplied in a gaseous state. The first stage reactor 130, 140 can be adjusted to a pressure of about 50 to about 500 bar and a temperature of about 50 to about 500 < 0 > C.

In the first-stage reactor (130, 140), the hydrogenation reaction in which the phthalate compound and hydrogen react with each other and converts to the corresponding cyclohexane dicarboxylate compound proceeds in the presence of the hydrogenation catalyst packed therein.

The hydrogenation apparatus 200 shown in FIG. 4 includes two first-stage reactors 130 and 140, and a first-stage reactor 130 and a second-stage reactor 140 are provided with a phthalate compound supply unit 110 and a hydrogen supply unit 120 ) Are independently connected to each other. The two first-stage reactors 130 and 140 may be all operated at the same time, or may be selectively operated in a manner that the two first-stage reactors 130 and 140 are operated by switching them in such a manner that one of them operates and the other does not operate. Although only two of the first-stage reactors 130 and 140 are shown in the drawing, a plurality of first and second reactors 130 and 140 may be provided.

 When a plurality of the first-stage reactors are provided, it is possible to operate in the other first-stage reactor even when the catalyst of the first-stage reactor is required to be replaced, thereby enabling continuous operation even when the catalyst is replaced .

The reaction product discharged from the first-stage reactor (130, 140) is transferred to the second-stage reactor (150), and the hydrogenation reaction proceeds in the second-stage reactor (150) in which the hydrogenation catalyst is independently charged. The reaction product includes not only the hydrogenation product of the phthalate compound but also the unreacted raw material phthalate compound and hydrogen, and the unreacted raw material undergoes the hydrogenation reaction again in the second-stage reactor 150.

The final reaction product from the second-stage reactor 150 may be separated and purified through a separation device 160 to be separated into a liquid reaction product and a gaseous unreacted product, and may be obtained as a final reaction product by removing impurities have.

According to the method and apparatus for hydrogenating a phthalate compound according to the present invention, it is possible to increase the service life of the catalyst by a multistage reaction and a switch reaction, and to perform stable operation for a long period of time.

Best Mode for Carrying Out the Invention Hereinafter, the function and effect of the present invention will be described in more detail through specific examples of the present invention. It is to be understood, however, that these embodiments are merely illustrative of the invention and are not intended to limit the scope of the invention.

<Examples>

Example 1

In order to perform the hydrogenation reaction, as shown in FIG. 3, a reactor having first and second stages of reactors was constructed. Each of the first and second stage reactors is in the form of a single tube, and the length of the reaction zone of the first stage reactor is 5 m and the length of the reaction zone of the second stage reactor is 10 m. In the outer jacket, the heat generated in the reactor was removed through hot oil, and the hydrogenation reaction was performed while maintaining the temperature. The catalyst used in the first and second stage reactors was ruthenium (Ru), and the pellet type was 3 mm in diameter and 3 mm in height.

Dioctyl terephthalate was preheated at a pressure of 150 bar and a temperature of 120 ° C and injected into the first stage reactor in a liquid phase via a pump. Hydrogen (H ₂ ) was also fed to the top of the first stage reactor separately from dioctyl terephthalate in gaseous state after preheating to the same pressure and temperature.

When the hydrogenation reaction of dioctyl terephthalate proceeds and the reaction conversion rate of the first stage reactor of the initial reaction (when the reaction is started and the product is released at the initial stage, that is, when the total catalyst activity is 1) is 70.5% After the reaction, the reaction product of the first stage reactor was transferred to the second stage reactor, and the second stage hydrogenation reaction was performed to obtain a final reaction conversion rate of 99.9%.

As the reaction progressed, the activity of the catalyst began to decrease at 1, and when the activity of the total catalyst reached 0.95, the catalyst of the first stage reactor was changed once.

Example 2

In Example 1, the hydrogenation reaction was carried out in the same manner as in Example 1 except that the length of the reaction zone of the first stage reactor was 7 m and the length of the reaction zone of the second stage reactor was 8 m.

When the hydrogenation reaction of dioctyl terephthalate proceeds, the reaction conversion rate of the first stage reactor of the initial reaction (when the reaction starts and the initial stage of the product is released, that is, the total catalyst activity is 1) is 81.3% After the reaction, the reaction product of the first stage reactor was transferred to the second stage reactor, and the second stage hydrogenation reaction was performed to obtain a final reaction conversion rate of 99.9%.

As the reaction progressed, the activity of the catalyst began to decrease at 1, and when the activity of the total catalyst reached 0.95, the catalyst of the first stage reactor was changed once.

Example 3

In Example 1, the hydrogenation reaction was carried out in the same manner as in Example 1 except that the length of the reaction zone of the first stage reactor was 10 m and the length of the reaction zone of the second stage reactor was 5 m.

When the hydrogenation reaction of dioctyl terephthalate proceeds and the reaction conversion rate of the first stage reactor of the initial reaction (when the reaction is started and the product is released at the initial stage, that is, when the total catalyst activity is 1) is 89.1% After the reaction, the reaction product of the first stage reactor was transferred to the second stage reactor, and the second stage hydrogenation reaction was performed to obtain a final reaction conversion rate of 99.9%.

As the reaction progressed, the activity of the catalyst began to decrease at 1, and when the activity of the total catalyst reached 0.95, the catalyst of the first stage reactor was changed once.

Comparative Example 1

The hydrogenation reaction was carried out in the same manner as in Example 1, except that a single-stage single-stage reactor (reaction zone length 15 m, no two-step reaction zone) was used.

As the hydrogenation reaction of dioctyl terephthalate proceeded, the activity of the catalyst began to decrease at 1, and the reaction proceeded without catalyst replacement until the total catalyst activity reached 0.95.

The catalyst operating time, total catalyst amount, initial reaction conversion rate, final reaction conversion rate, final product purity, operating period per unit catalyst, etc. of the catalysts of Examples 1 to 3 and Comparative Example 1 are shown in Table 1 below.

1 shows changes in catalytic activity with time in Examples 1 to 3 and Comparative Example 1. As shown in Fig.

Operable
Period (A) * Total catalyst
usage
(B) Initial Reaction Conversion ** final
Reaction conversion rate *** final
product
water Operable period per unit catalyst
(A / B) Comparative Example 1 Preparation
(A / B)
Growth rate Example 1 110 day 2.4 tons 70.5% 99.9% 98% 45.0 30.8%
increase Example 2 117 day 2.64 tons 81.3% 99.9% 98% 43.6 26.7%
increase Example 3 123 day 3 tons 89.1% 99.9% 98% 40.3 17.2%
increase Comparative Example 1 67 day 1.8 tons - 99.9% 98% 34.4 -

* Operation period : When the activity of the entire catalyst is 1, the catalyst of the first-step reaction zone (reactor) is replaced when the activity of the entire catalyst reaches 0.95, while the hydrogenation reaction is continuously performed, And again the operation time taken until the total catalyst activity reaches 0.95.

** Initial Reaction Conversion: This is the conversion rate of the first reaction zone at the initial stage of the reaction in which the product comes out of the reactor.

*** Final reaction conversion rate: The final reaction conversion rate at the time when the reaction is completed.

Referring to Table 1 and FIG. 1, when the reaction zone is divided into the first stage and the second stage as in the first to third embodiments and only the catalyst in the first stage reaction zone where the reaction is concentrated is operated, 1, the operating period and the total amount of catalyst used were increased. It can be seen that the catalysts of Examples 1 to 3 were increased by at least 17% and at most 30% more than Comparative Example 1 in terms of the operation period per unit catalyst.

From these results, it is confirmed that the reaction zone is divided into multiple stages and the catalyst is replaced only in the aged reaction zone as the reaction progresses, thereby improving the overall catalyst life and stable operation over a longer period of time.

10, 110: phthalate compound supply part
20, 120: hydrogen supply unit
30, 130, 140: a first stage reactor
40, 150: Second stage reactor
50, 160: Separation device
100, 200: hydrogenation device

Claims (6)

Introducing a phthalate compound and hydrogen into a first-stage reactor filled with a hydrogenation catalyst to react;
Introducing a reaction product discharged from the first-stage reactor into a second-stage reactor connected to the first-stage reactor and filled with a hydrogenation catalyst, and reacting; And
And independently replacing the hydrogenation catalysts of the first and second stages of the reactor according to the degree of deactivation of the hydrogenation catalyst packed in the first and second stages of the reactor, respectively.
The method according to claim 1,
Wherein independently replacing each of the hydrogenation catalysts of the first and second stages of the reactor comprises replacing the catalyst of the first stage reactor during the reaction in the second stage reactor, Way.
The method according to claim 1,
When the activity of the total hydrogenation catalyst packed in the first and second stage reactors reaches 0.95 when the initial activity of the total hydrogenation catalyst packed in the first and second stage reactors is 1, A method of hydrogenating a phthalate compound, wherein the catalyst is replaced.
The method according to claim 1,
A hydrogenation method of a phthalate compound which performs a hydrogenation reaction in a first stage reactor until a reaction conversion rate of a phthalate compound introduced into the first stage reactor calculated by the following formula 1 reaches 40% to 95%
[Formula 1]

The method according to claim 1,
Wherein the hydrogenation catalyst comprises at least one selected from the group consisting of Ru, Pd, Rh, Pt and Ni.
The method according to claim 1,
Wherein the reaction product is a hydrogenated compound of the phthalate compound and a phthalate compound containing unreacted phthalate compound and hydrogen in the first stage reactor.

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