TW202112732A - Process for hydrogenation of phthalate compound - Google Patents

Abstract

Provided is a method of hydrogenation of a phthalate compound. Specifically, in one embodiment of the present invention, provided is a method of obtaining a hydrogenation product, of which aromaticity is controlled from 2.5% to 5.5%, by controlling each of the average temperature and the maximum-minimum temperature difference inside a reactor to satisfy a specific range during the hydrogenation of the phthalate compound.

Description

Hydrogenation method of phthalate compound

This application is based on and claims the priority of Korean Patent Application No. 10-2019-0115255 filed with the Korean Patent Office on September 19, 2019, which is incorporated herein by reference in its entirety.

The present invention relates to a method for hydrogenating phthalic acid ester compounds.

Phthalate-based compounds (phthalate-based compounds) are materials widely used as plasticizers for plastics, especially polyvinyl chloride (PVC). For example, phthalate-based compounds can have a variety of applications, such as electrical and electronic products, drugs, paint pigments, lubricants, binders, surfactants, adhesives, tiles, food containers, packaging Materials, etc.

However, because some phthalate compounds are considered to cause environmental pollution and human endocrine interference problems, in advanced countries such as Europe and the United States, restrictions on their use are more stringent. Especially in phthalate-based plasticizers, di(2-ethylhexyl) phthalate (DEHP), butyl benzyl Products such as phthalate (BBP) and di-n-butyl phthalate (DBP) are suspected to be environmental hormones, that is, endocrine disruptors that inhibit or destroy the effects of hormones in the human body. Therefore, these products are regulated the trend of.

For this reason, efforts are currently being made to develop an environmentally friendly plasticizer, which may have no problems with environmental hormones, and at the same time may have the same properties as existing plasticizers. One of the methods is to use a compound prepared through a benzene ring contained in a hydrogenated phthalate compound.

Compared with the phthalate compound as the starting material, the hydrogenated product of the phthalate compound has a lower viscosity and surface migration, thereby helping to improve the resin including the same plasticizer Dispersibility and processability of the composition.

However, based on the hydrogenation reaction of phthalate compounds, the loss of volatiles may increase. When a hydrogenated product with high volatile loss is used as a plasticizer, the amount of plasticizer released from the resin composition may increase.

Therefore, when preparing an environmentally friendly plasticizer through the hydrogenation reaction of phthalate compounds, it is necessary to control the physical properties of the product such as viscosity, surface migration and volatile loss within an appropriate range.

technical problem

In order to provide an environmentally friendly plasticizer, its physical properties such as viscosity, surface migration, volatile loss, etc. are within a suitable range, and a method for obtaining a product whose aroma is controlled within a specific range is provided. During the hydrogenation reaction of the phthalate compound, the average temperature and the maximum-minimum temperature difference in the reactor are simultaneously controlled.

Technical means

Specifically, in an embodiment of the present invention, a method for hydrogenating a phthalate compound is provided, thereby obtaining a hydrogenated product having an aromaticity of 2.5% to 5.5% according to the following equation 1:

[Equation 1] Aromaticity (%) = 100*(B/A)

In Equation 1, A and B respectively represent the measured value of the hydrogen nuclear magnetic resonance spectroscopy (H-NMR) of the hydrogenated product, where A represents the total number of hydrogen atoms included in the hydrogenated product, and B represents the hydrogenated product The number of hydrogen atoms contained in the aromatic functional group.

More specifically, in order to obtain a hydrogenated product whose aromaticity is controlled within the above-mentioned range, during the hydrogenation reaction of the phthalate compound, the average temperature in the reactor is controlled within the range of 125°C to 160°C, At the same time, the maximum-minimum temperature difference in the reactor is controlled within the range of 4.5°C to 9.0°C. The reaction is included in the reactor and reacts the phthalate compound with hydrogen in the presence of a hydrogenation catalyst. step.

Invention effect

According to one embodiment, by controlling the average temperature and the maximum-minimum temperature difference in the reactor to meet the specific range during the hydrogenation reaction of the phthalate compound, the aromaticity can be controlled in the range of 2.5% to 5.5% The hydrogenated product.

The hydrogenated product whose aromaticity is controlled within the above range can exhibit physical properties (such as viscosity, surface migration, volatile loss, etc.) within an appropriate range, so it can be used as a plasticizer with better quality.

The present invention can be variously modified and has various exemplary embodiments, and specific exemplary embodiments are illustrated and explained in detail. However, this is not intended to limit the present invention to specific exemplary embodiments, and it must be understood that the present invention includes all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention. When it is determined that the detailed description of the known technology related to the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted.

Although terms including ordinal numbers such as first and second can be used to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the patent scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

Unless expressed differently in the context, the singular expression may include the plural expression. It should also be understood that when used in this specification, the term "including" or "having" designates the existence of the described features, integers, steps, operations, components, parts, or combinations thereof, but does not exclude one or more other The existence or addition of features, integers, steps, operations, components, parts, or combinations thereof.

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

The present invention relates to a method for hydrogenating a phthalate ester compound, the method comprising a step of reacting a phthalate ester compound with hydrogen in a reactor in the presence of a hydrogenation catalyst.

Generally, when a phthalate ester compound reacts with hydrogen in the presence of a hydrogenation catalyst, the hydrogenated product has a reduced aromaticity compared to the phthalate ester compound as a starting material.

As the aromaticity of the hydrogenated product decreases, the viscosity and surface migration tend to decrease, while the loss of volatiles tends to increase. Here, "volatile matter loss" may be affected by various factors, such as molecular weight, molecular structure, or polarity of the compound.

Since the hydrogenated product has lower viscosity and surface migration, it can be beneficial to improve the dispersibility and processability of the resin composition, and the hydrogenated product is used as a plasticizer in the resin composition.

However, due to the hydrogenation reaction of the phthalate compound, the loss of volatiles may increase, so when the hydrogenated product with high volatile loss is used as a plasticizer, the amount of the plasticizer separated from the resin composition may be increase.

Therefore, it is necessary to reduce the viscosity and surface migration by controlling the aromaticity of the hydrogenated product within an appropriate range, and at the same time achieve the control of the volatile loss within an appropriate range.

An embodiment of the present invention provides a method for obtaining a hydrogenated product with an aromaticity of 2.5% to 5.5%, and the method is derived from the above-mentioned demand. The hydrogenated product whose aromaticity is controlled within the technical range can exhibit physical properties within an appropriate range, such as viscosity, surface migration, volatile loss, etc., so as to provide a better quality plasticizer.

Specifically, in an embodiment of the present invention, in order to obtain a hydrogenated product whose aromaticity is controlled within the above range, during the hydrogenation reaction of the phthalate compound, the average temperature and the maximum-minimum temperature in the reactor The difference is controlled within a range of 125°C to 160°C and 4.5°C to 9.0°C, respectively, and the reaction includes a step of reacting a phthalate compound with hydrogen in the presence of a hydrogenation catalyst in a reactor.

In fact, in the following experimental examples, it was confirmed that during the reaction process of phthalate compounds, when the average temperature in the reactor was controlled in the range of 125°C to 160°C, at the same time, the highest-lowest temperature in the reactor When the temperature difference is controlled within the range of 4.5°C to 9.0°C, a hydrogenated product with an aromaticity of 2.5% to 5.5% can be obtained, and the hydrogenated product whose aromaticity meets the above range has viscosity, surface migration and volatilization within an appropriate range The material loss is different from the case where the average temperature is the same as the above, but the maximum-minimum temperature difference exceeds the upper limit.

Compared with the general hydrogenation reaction, this method can further reduce the maximum-minimum temperature difference (Δt) under the same average temperature (T) in the reactor and can react uniformly in the entire reactor, so it can obtain aromaticity. Products that are controlled within an appropriate range. Here, the temperature difference refers to the difference between the highest temperature and the lowest temperature in the reactor, and can be measured from multiple temperature sensors installed at different heights of the reactor.

The aromaticity of the product obtained according to an embodiment is a factor that can be controlled by changing the average temperature, the maximum-minimum temperature difference, or both of the above-mentioned recommended ranges in the reactor.

For example, the average temperature in the reactor during the hydrogenation reaction can be controlled at 125°C or higher, 126°C or higher, 127°C or higher, 128°C or higher, 129°C or higher, or 130°C or higher. , And at 160°C or lower, 159°C or lower, 158°C or lower, 157°C or lower, 156°C or lower, or 155°C or lower.

In addition, during the hydrogenation reaction, the maximum-minimum temperature difference in the reactor can be controlled at 4.5°C or higher, 4.6°C or higher, 4.7°C or higher, 4.8°C or higher, 4.9°C or higher, 5.0°C or higher or 5.1°C or higher, and at 9.0°C or lower, 8.9°C or lower, 8.8°C or lower, 8.7°C or lower, 8.6°C or lower, 8.5°C or lower, 8.4°C or lower, 8.3°C or lower, 8.2°C or lower, 8.1°C or lower, 8.0°C or lower, or 7.9°C or lower.

When the average temperature in the reactor, the maximum-minimum temperature difference, or both can be controlled within the above-mentioned example ranges, the aromaticity of the resulting product can be controlled at 2.5% or higher, 2.6% or higher, 2.7% or higher High, 2.8% or higher, 2.9% or higher or 3.0% or higher, and 5.5% or lower, 5.4% or lower, 5.3% or lower, 5.2% or lower, 5.1% or higher Low or within the range of 5.1% or less

More specifically, during the hydrogenation reaction, as the average temperature and the maximum-minimum temperature difference in the reactor increase within the above-exemplified range, the aromaticity of the resultant product may decrease. As the aromaticity decreases, the initial viscosity and surface migration may decrease, and the loss of volatiles may increase.

In this regard, considering the target value of physical properties such as viscosity, surface migration, volatile loss, etc., the aromaticity of the product can be designed, and the process conditions can be controlled within the above-mentioned example range (ie, the average temperature and the average temperature in the reactor). Maximum-minimum temperature difference).

At the same time, when the average temperature and the maximum-minimum temperature difference in the reactor are more sensitively controlled during the hydrogenation reaction to meet the relationship of the following equation 2, it may be more advantageous to obtain products with the desired range of aromaticity and physical properties :

[Equation 2] 0.13*T-12.3 ≤ Δt ≤ 0.13*T-10.3

In Equation 2, T represents the average temperature (°C) in the reactor during the reaction; and Δt represents the difference (°C) between the highest temperature and the lowest temperature in the reactor during the reaction.

In order to comply with the relationship of Equation 2, during the hydrogenation reaction, the reactor can be controlled to keep the temperature difference per unit length (meter) below 3°C, for example below 2°C, to avoid local heat generation. Since the temperature difference per unit length of the reactor is better, the lower limit is not limited, but it may be, for example, 1°C or higher, preferably 0°C. The temperature difference can be measured from a plurality of temperature sensors installed according to the height of the reactor.

In addition, during the hydrogenation reaction, ^{the maximum reaction volume per actual reaction volume (m 3} ) of the reactor filled with the catalyst can be maintained at 20 kmol/h or less, such as 15 kmol/h or less, thereby preventing the reaction Local heating in the device. Here, by sampling each product according to the height of the reactor, the reaction amount can be calculated based on the change in concentration.

In order to achieve the above-mentioned control of the reaction volume in the reactor, the mass flux or concentration of the reactants can be controlled as described above, or an inert gas or an inert liquid can be added together with the reactants for this purpose. Control the amount.

For example, the mass flux of the phthalate compound injected into the reactor (that is, the mass flux per unit area (m ² ) of the catalyst filling the reactor) may be 10000 kg*hr ^-1 *m ^-2 To 15000 kg*hr ^-1 *m ^-2 , specifically, 10000 kg*hr ^-1 *m ^-2 to 13000 kg*hr ^-1 *m ^-2 .

When the mass flux of the phthalate compound is less than 10000 kg*hr ^-1 *m ^{-2 per unit area (m 2} ), the input raw material is insufficient, resulting in a problem of reduced productivity. When the mass flux of the phthalate compound is greater than 15000 kg*hr ^-1 *m ^-2 , the amount of the liquid phase raw material injected into the reactor at one time becomes too large, which increases the film thickness of the liquid phase raw material on the catalyst surface. Therefore, the permeation of hydrogen becomes difficult, and it is difficult to perform the hydrogenation reaction. Side reactions increase and local heating occurs, which results in a serious problem in the temperature difference of the reactor.

At the same time, in order to minimize side reactions and increase process productivity by optimizing the ratio of reactants, based on 1 mol of phthalate compound, the amount of hydrogen injected into the reactor can be 3 mol or more , Or 4 mol or more, and 300 mol or less, or 100 mol or less, or 50 mol or less, or 30 mol or less.

Based on 1 mol of the phthalate compound, when the amount of hydrogen is less than 3 mol so as to be too small, the reaction conversion rate becomes low, and therefore it is difficult to achieve a conversion rate of 95% or higher. When the amount of hydrogen is greater than 300 mol and is too large, the residence time of the liquid-phase feed droplets in the reactor becomes shorter due to hydrogen, so the conversion rate may be reduced or the by-products may increase, or the life of the catalyst may be rapidly reduced . From this viewpoint, the amount of hydrogen is preferably within the above-mentioned range.

As another method of controlling the temperature difference and the reaction amount in the reactor, a method of dispersing the reaction heat by installing a cooling element can be used. The cooling element through the refrigerant circulation is installed inside or outside the reactor.

Regarding the refrigerant, refrigerants known in the art can be used without limitation, such as cooling water, methane-based refrigerants, fluorine-substituted or unsubstituted lower alkene having 1 to 5 carbon atoms (lower alkene) and ether ( ether) mixed refrigerant. The type of cooling element is not particularly limited, but indirect cooling methods (such as heat exchangers, cooling jackets, etc.) and direct cooling methods (such as inert gas, inert liquid, etc.) can be used.

As mentioned above, when the hydrogenation reaction is carried out by controlling the temperature difference in the reactor, the reaction can occur uniformly in the reactor, thereby controlling the aromaticity of the hydrogenation product, and by uniformly loading the catalyst in the upper/lower part of the reactor. Improve the life of the catalyst.

The phthalate compound is the target of hydrogenation, and hydrogen is added to the benzene ring of the phthalate compound through hydrogenation to convert it into the corresponding cyclohexane dicarboxylate compound.

The phthalate compound may be selected from the group consisting of phthalate, terephthalate, isophthalate, and the corresponding carboxylic acid compound. One or more of the group.

First, the phthalate compound can be represented by the following Chemical Formula 1: [Chemical Formula 1]

In Chemical Formula 1, R1 and R1' are each independently the same or different from each other, and are hydrogen, or have 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, more preferably 5 to 20 carbon atoms, The most preferred is a straight or branched chain alkyl group of 5 to 10 carbon atoms.

Specific examples of the phthalate compound may include dibutyl phthalate (DBP), dihexyl phthalate (DHP), and dioctyl phthalate (dioctyl phthalate, DBP). DOP), di-n-octyl phthalate (DnOP), diisononyl phthalate, diisodecyl phthalate (DIDP), etc. , But not limited to this. These compounds can be used alone or in combination.

The terephthalate compound can be represented by the following Chemical Formula 2: [Chemical Formula 2]

In Chemical Formula 2, R2 and R2' are each independently the same or different from each other, and are hydrogen, or have 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, more preferably 5 to 20 carbon atoms, Most preferably, it is a straight or branched chain alkyl group of 5 to 10 carbon atoms.

Specific examples of terephthalate compounds may include dibutyl terephthalate (DBTP), dioctyl terephthalate (DOTP), diisononyl terephthalate (diisononyl terephthalate (DINTP) or diisodecyl terephthalate (DIDTP), but not limited thereto. These compounds can be used alone or in combination.

The isophthalate compound can be represented by the following Chemical Formula 3: [Chemical Formula 3]

In Chemical Formula 3, R3 and R3' are each independently the same or different from each other, and are hydrogen, or have 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, more preferably 5 to 20 carbon atoms, Most preferably, it is a straight or branched chain alkyl group of 5 to 10 carbon atoms.

Specific examples of the isophthalate compound may include dibutyl isophthalate (DBIP), dioctyl isophthalate (DOIP), diisononyl isophthalate (diisononyl isophthalate, DINIP), diisodecyl isophthalate (DIDIP), etc., but not limited to this. These compounds can be used alone or in combination.

Preferably, dioctyl terephthalate (DOTP) can be used as the phthalate compound.

The purity of the phthalate compound may be about 99% or higher, preferably about 99.5% or higher, more preferably about 98% or higher, but is not limited thereto. Any commercially available phthalate compound of quality and purity can be used.

The hydrogenation process of the phthalate compound can be carried out in the liquid phase or in the gas phase. According to an exemplary embodiment of the present invention, the hydrogenation reaction may be performed by using a liquid phthalate compound and gas phase hydrogen.

The temperature and pressure conditions of the gas-phase raw material and the liquid-phase raw material introduced into the reactor are not particularly limited. However, the gas phase feedstock can be controlled within a pressure range of about 100 bar to about 200 bar, preferably about 130 bar to about 160 bar, and the temperature range can be about 100°C to about 200°C, preferably about 130°C to about 130°C. At about 180°C, the liquid phase raw material can be controlled within a pressure range of about 100 bar to about 200 bar, preferably about 130 bar to about 160 bar, and within a temperature range of about 100°C to about 200°C, preferably From about 130°C to about 180°C.

Regarding this, the step of increasing the pressure and temperature of the liquid phase phthalate compound before the reaction may be further included, and the liquid phase phthalate compound and gas phase hydrogen whose pressure and temperature are increased may be supplied to the equipment. In a reactor with a hydrogenation catalyst, the liquid phase phthalate compound and gas phase hydrogen whose pressure and temperature are increased can be allowed to react with each other in the reactor in the presence of the hydrogenation catalyst. Here, the average temperature and the maximum/minimum temperature difference in the reactor must be controlled as described above.

The hydrogenation catalyst may include a transition metal as an active ingredient, and preferably may include one or more selected from the group consisting of ruthenium (Ru), palladium (Pd), rhodium (Rh), and platinum (Pt).

The hydrogenation catalyst can be used after being supported on a carrier. In this regard, as a carrier, any carrier known in the art can be used without limitation. Specifically, the support can be zirconia (ZrO ₂ ), titania (TiO ₂ ), alumina (Alumina, Al ₂ O ₃ ), silica (SiO ₂ ), etc.

When the hydrogenation catalyst is supported on the carrier, based on 100 parts by weight of the carrier, the amount of the active ingredient of the hydrogenation catalyst may preferably be 3 parts by weight or less, or 2 parts by weight. Or less, or 1 part by weight or less, and 0.1 parts by weight or more, or 0.3 parts by weight or more. Based on 100 parts by weight of the carrier, when the amount of the hydrogenation catalyst is greater than 3 parts by weight, the reaction will occur quickly on the surface of the catalyst, and during this process, side reactions will also increase, which may lead to by-products The problem of rapid increase in volume. When the amount of the hydrogenation catalyst is less than 0.1 parts by weight, the yield of the hydrogenation reaction may decrease due to the insufficient amount of the catalyst. Therefore, the above range is preferable.

In the present invention, the hydrogenation conditions are not particularly limited. However, the reaction pressure may be, for example, 50 bar or higher, or 100 bar or higher, or 130 bar or higher, and 220 bar or lower, or 200 bar or lower, or 180 bar or lower. When the reaction pressure is less than 50 bar, there will be many problems, and the reaction hardly occurs, so an excessive amount of the catalyst is consumed, the residence time becomes too long, and the by-products increase. When the reaction pressure exceeds 200 bar, excessive energy (such as electrical energy) is required during the process operation, so there is a problem that the manufacturing cost of equipment such as the reactor may be greatly increased. Therefore, the above range is preferable.

Through the hydrogenation reaction, the aromatic ring of the phthalate compound is hydrogenated to be converted into the corresponding cyclohexanedicarboxylate compound.

After the reaction is terminated, the produced liquid phase hydrogenation product and the unreacted gas phase raw material are separated from each other. The separated gas phase feedstock can be recycled in the hydrogenation process. The recovered hydrogenated product can be finally separated through a pressure reduction and cooling process.

Fig. 1 is a schematic diagram of a hydrogenation reaction apparatus used in the hydrogenation method of the present invention. 1, the hydrogenation reaction device may be composed of heat exchangers a and b (heat exchanger), reactor c, gas-liquid separator d, and the like.

The heat exchangers a and b are used to heat the gas phase raw material 1 and the liquid phase raw material 3 before they are introduced into the reactor c, and can be omitted as necessary.

The gas phase raw material 2 and the liquid phase raw material 4 are introduced into a pipe-type reactor c (pipe-type reactor) and undergo a hydrogenation reaction, and the inside of the reactor c is filled with a hydrogenation catalyst. The reactor may further include an external jacket for heat removal in order to control the heat of reaction. In this regard, the gas-phase feedstock 2 may be introduced into the upper or lower part of the reactor, and the liquid-phase feedstock 4 may be introduced into the upper part of the reactor.

In the hydrogenation reaction of the phthalate compound, since the gas phase raw material and the liquid phase raw material react with each other on the surface of the solid catalyst, they must be used at a flow rate sufficient to form a film on the surface of the solid catalyst. For this reason, it is suitable to use the operation method of applying the liquid phase raw material from the upper part little by little by gravity. On the contrary, when the liquid-phase raw material is introduced into the lower part, the solid catalyst is submerged by the liquid-phase reactant. Therefore, the gas-phase reactant may have difficulty penetrating the solid catalyst, which may be unsuitable.

The reaction mixture 5 discharged from the reactor c is transferred to the gas-liquid separator d, in which the liquid-phase reaction product 7 and the unreacted gas-phase raw material 6 are separated from each other. The separated reaction product 7 can be recovered and further subjected to a purification process, and the unreacted gas phase feedstock 6 is recycled for discharge or recycling.

However, the position of each element shown in FIG. 1 may be changed, and if necessary, other elements not shown in FIG. 1 may be included. Therefore, the hydrogenation method of the present invention is not limited to the equipment and process sequence shown in FIG. 1.

The aromatic reaction product controlled by the hydrogenation method of an embodiment has low viscosity and low surface migration, and relatively little permeates to the surface of the product even after long-term use, thus showing its superiority as a plastic plasticizer characteristic.

The hydrogenated phthalate compound or hydrogenated terephthalate compound prepared as above can be effectively used as a plasticizer. Specifically, plasticizers including phthalate compounds or terephthalate compounds can be suitably used selected from polystyrene, polyurethane, polybutadiene, polysiloxane, thermoplastic elastomers and copolymers thereof. The plasticizer of the resin in the group consisting of substances.

The resin composition including the resin can be used in various products. For example, the resin composition can be applied to products such as stabilizers, paints, inks, liquid phase foaming agents (master batches), adhesives, and the like. The resin composition can also be used to prepare food packaging films (e.g. packaging), industrial films, compounds (compounds), decorative sheets, decorative tiles, soft sheets, rigid sheets, wires and cables, wallpapers, foam mats, Artificial leather, floor materials, tarps, gloves, sealants, refrigerator gaskets, hoses, medical equipment, geogrids, mesh tarps, toys, stationery, insulating tape, clothing coatings, poly for clothing or stationery Vinyl chloride labels, bottle cap liners, stoppers for industrial or other purposes, artificial baits, components in electronic components (such as sleeves), automotive interior materials, adhesives and coating agents, but not limited to these.

Hereinafter, the action and effect of the present invention will be described in more detail with reference to specific examples of the present invention. However, these examples are for illustrative purposes only, and the scope of the present invention is not limited thereto.

Instance

Example 1

Dioctyl terephthalate (DOTP) with a purity of 99% was injected into the reactor, and the hydrogenation reaction was carried out at a reaction pressure of 150 bar.

The mass flux of DOTP per unit area (m ² ) is 12000 kg*hr ^-1 *m ^-2 , and hydrogen is injected so that the molar ratio of hydrogen/DOTP is 6.

The reactor is a single-tube reactor, in which the total length of the part filled with the catalyst in the tube is 2.0 m, and the maximum-minimum temperature difference is controlled to meet 7.9°C. At the same time, the cooling fluid (Therminol 55) An external kit is used to control the average temperature inside the reactor and make it meet 155°C. In addition, the reaction amount per unit volume (m ³ ) of the reactor during the reaction is 20 kmol/h or less.

The catalyst used in the reactor is a ruthenium catalyst, wherein based on 100 parts by weight of alumina (Al ₂ O ₃ ) support, the content of ruthenium is 0.5 parts by weight, and the size is 3 mm in diameter and 3 mm in height The cylindrical shape.

For reference, in each reaction process of Example 1, the following Examples 2 and 3 and Comparative Examples 1 to 9, the average temperature and the maximum-minimum temperature difference in the reactor are recorded in Table 1 below, and each condition is calculated Whether it satisfies Equation 2.

Example 2

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 140°C and 6.4°C, respectively.

Example 3

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 130°C and 5.1°C, respectively.

Comparative example 1

Dioctyl terephthalate (DOTP) with a purity of 99% without hydrogenation was used as Comparative Example 1.

Comparative example 2

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 100°C and 1.8°C, respectively.

Comparative example 3

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 110°C and 2.8°C, respectively.

Comparative example 4

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 120°C and 3.9°C, respectively.

Comparative example 5

The hydrogenation reaction was carried out in the same manner as in Example 1, except that the average temperature and the maximum-minimum temperature difference in the reactor during the hydrogenation reaction were changed to 180°C and 13°C, respectively.

Comparative example 6

The hydrogenation reaction was carried out in the same manner as in Example 1, except that ^{the mass flux of DOTP per unit area (m 2} ) was 20000 kg*hr ^-1 *m ^-2 , and the average temperature in the reactor during the hydrogenation reaction The maximum-minimum temperature difference was changed to 140°C and 10.6°C, respectively, and the reaction volume per unit volume (m ³ ) of the reactor during the reaction was changed to 30 kmol/h or less.

Comparative example 7

The hydrogenation reaction was carried out in the same manner as in Example 1, except that ^{the mass flux of DOTP per unit area (m 2} ) was 20000 kg*hr ^-1 *m ^-2 , and the average temperature in the reactor during the hydrogenation reaction The maximum-minimum temperature difference was changed to 155°C and 13.1°C, respectively, and the reaction volume per unit volume (m ³ ) of the reactor during the reaction was changed to 30 kmol/h or less.

Comparative example 8

The hydrogenation reaction was carried out in the same manner as in Example 1, except that ^{the mass flux of DOTP per unit area (m 2} ) was 20000 kg*hr ^-1 *m ^-2 , and the average temperature in the reactor during the hydrogenation reaction The maximum-minimum temperature difference becomes 165°C and 14.3°C, respectively, and the reaction volume per unit volume (m ³ ) of the reactor during the reaction is changed to 30 kmol/h or less.

Comparative example 9

The hydrogenation reaction was carried out in the same manner as in Example 1, except that ^{the mass flux of DOTP per unit area (m 2} ) was 20000 kg*hr ^-1 *m ^-2 , and the average temperature in the reactor during the hydrogenation reaction The maximum-minimum temperature difference was changed to 175°C and 15.2°C, respectively, and the reaction volume per unit volume (m ³ ) of the reactor during the reaction was changed to 30 kmol/h or less.

Table 1 Hydrogenation conditions Calculate whether the hydrogenation conditions meet equation 2 Average temperature (°C) Maximum-minimum temperature difference (°C) 0.13*T-12.3 (°C) 0.13*T-10.3 (°C) Calculation results Example 1 155 7.9 7.85 9.85 O Example 2 140 6.4 5.9 7.9 O Example 3 130 5.1 4.6 6.6 O Comparative example 1 (No hydrogenation reaction) Comparative example 2 100 1.8 0.7 2.7 O Comparative example 3 110 2.8 2 4 O Comparative example 4 120 3.9 3.3 5.3 O Comparative example 5 180 13 11.1 13.1 O Comparative example 6 140 10.6 5.9 7.9 X Comparative example 7 155 13.1 7.85 9.85 X Comparative example 8 165 14.3 9.15 11.15 X Comparative example 9 175 15.2 10.45 12.45 X

Experimental example 1

After completing the hydrogenation reactions of the Examples and Comparative Examples, unreacted gas phase raw materials were separated from the reaction mixture, and various hydrogenated products were obtained.

The physical properties of various hydrogenated products were evaluated by the following methods, and the evaluation results of the physical properties are recorded in Table 2 below.

Aromaticity: Each hydrogenated product was analyzed by hydrogen nuclear magnetic resonance spectroscopy (H-NMR), and the aromaticity was calculated according to Equation 1 below, and the results are recorded in Table 2 below.

[Equation 1] Aromaticity (%) = 100*(B/A)

In Equation 1, A and B respectively represent the measured value of hydrogen nuclear magnetic resonance spectroscopy (H-NMR) of the hydrogenated product, where A represents the total number of hydrogen atoms included in the hydrogenated product, and B represents the aromatic functional group contained in the hydrogenated product The number of hydrogen atoms in.

Table 2 Hydrogenation conditions Hydrogenated products Average temperature (°C) Maximum-minimum temperature difference (°C) Aromaticity (%) Example 1 155 7.9 3.0 Example 2 140 6.4 4.2 Example 3 130 5.1 5.0 Comparative example 1 (No hydrogenation reaction) 10.5 Comparative example 2 100 1.8 8.4 Comparative example 3 110 2.8 7.4 Comparative example 4 120 3.9 6.3 Comparative example 5 180 13 2.1 Comparative example 6 140 10.6 6.1 Comparative example 7 155 13.1 5.3 Comparative example 8 165 14.3 5.1 Comparative example 9 175 15.2 5.1

Experimental example 2

100 parts by weight of polyvinyl chloride, 65 parts by weight of various plasticizer compositions (hydrogenated products) of the examples and comparative examples, 140 parts by weight of filler (OMIA-10), 4 parts by weight Several parts by weight of titanium dioxide (TiO ₂ ), 1.6 parts by weight of stabilizer (LFX-035H), 0.5 parts by weight of dispersant, 5 parts by weight of diluent (D240R) and 8.8 parts by weight of viscosity The sex inhibitor (BYK 5130) was mixed with each other in a Mathis mixer for 10 minutes to prepare various plastisols. The use and evaluation of various plastisols of the examples and comparative examples prepared accordingly are as follows.

Initial viscosity and viscosity change rate with time: each plastisols were aged in an oven at a constant temperature of 25°C for 1 hour, and then measured with a Brookfield viscometer (spindle #4, 20 RPM). In addition, the change in viscosity after 1 day was measured under the same conditions, and the rate of change in viscosity over time was calculated according to Equation 3 below.

[Equation 3] Change rate of viscosity after 1 day (%) = {(Initial viscosity of plastisol)/(Viscosity of plastisol in 1 day)}

Migration loss: According to KSM-3156, a Mathis oven is used to prepare various plastisol samples with a thickness of 2 mm or more, and oil paper is attached to the two surfaces of each sample, and then It carries a weight of 5 kg and is stored in an oven at 60°C for 7 days. Remove each sample from the oven and remove the oil paper from both surfaces of the sample. Measure the weight before and after placing it in the oven, and calculate the migration loss according to Equation 4 below.

[Equation 4] Migration loss (%) = [(Initial weight of the sample at room temperature-Weight of the sample after being placed in the oven) / Initial weight of the sample at room temperature] x 100

Heating loss: At the same time, 30 grams of various plasticizer compositions (hydrogenated products) prepared in the Examples and Comparative Examples were stored in an oven at 200°C for 1 hour, and then calculated from the weight change according to Equation 5 below Heating loss.

[Equation 5] Heating loss (wt%) = [(initial weight of plasticizer composition-weight of plasticizer composition after storage at 200°C for 1 hour) / initial weight of plasticizer composition] х 100

table 3 Hydrogenation conditions Average temperature (°C) Maximum-minimum temperature difference (°C) Example 1 155 7.9 Example 2 140 6.4 Example 3 130 5.1 Comparative example 1 - Comparative example 2 100 1.8 Comparative example 3 110 2.8 Comparative example 4 120 3.9 Comparative example 5 180 13 Comparative example 6 140 10.6 Comparative example 7 155 13.1 Comparative example 8 165 14.3 Comparative example 9 175 15.2 Evaluation of the physical properties of hydrogenated products Aromaticity (%) Initial viscosity (1 hour, 20 rpm) Stickiness after 1 day (20 rpm) Rate of change over time Surface migration (%) Volatile loss (%) Example 1 3.0 3240 3310 1.02 9.10 0.41 Example 2 4.2 3460 3500 1.01 9.25 0.39 Example 3 5.0 3600 3700 1.03 9.29 0.38 Comparative example 1 10.5 5770 5940 1.03 10.44 0.34 Comparative example 2 8.4 4550 4750 1.04 9.88 0.36 Comparative example 3 7.4 4110 4350 1.06 9.81 0.37 Comparative example 4 6.3 3860 4060 1.05 9.80 0.38 Comparative example 5 2.1 3060 3180 1.04 8.98 0.44 Comparative example 6 6.1 3820 4010 1.05 9.79 0.38 Comparative example 7 5.3 3680 3830 1.04 9.73 0.39 Comparative example 8 5.1 3640 3790 1.04 9.70 0.39 Comparative example 9 5.1 3640 3790 1.04 9.70 0.39

According to Table 2, compared with the phthalate compound of the starting material (such as Comparative Example 1), all the hydrogenated products of Comparative Examples 2 to 9 and Examples 1 to 3 showed lower aromaticity and lower viscosity. These results are attributed to the addition of hydrogen to the benzene contained in the phthalate compound.

However, as the aromaticity of the hydrogenated product decreases, the loss of volatiles may increase. Therefore, it is very important to obtain a plasticizer and control the volatile loss of the plasticizer within an appropriate range so as to maintain a balance with other properties.

Specifically, in Comparative Examples 2 to 9, products with an aromaticity greater than 5.0% were obtained, and the volatile loss of each product was appropriately within the range of 0.36% to 0.44%, but the initial viscosity reached a minimum of From 3640 to a maximum of 4550, and one day later, the viscosity further increased to a minimum of 3790 and a maximum of 4750, and the surface migration reached a minimum of 9.70 and a maximum of 9.88.

On the contrary, in Examples 1 to 3, products with aromaticity falling within the range of 3.0% to 5.0% were obtained, and the volatile loss of each product was at the same level as that of Comparative Examples 2 to 9, but the initial viscosity was 3600 or lower, the viscosity after 1 day is 3700 or lower, and the surface migration is 9.29% or lower, which means that they have a significant improvement in viscosity and surface migration.

Different from Comparative Examples 2 to 9, the remarkable point of Examples 1 to 3 is that by controlling the hydrogenation conditions of the phthalate compound within a specific range, the viscosity and surface migration can be reduced, and the volatiles of the product can be lost. Control at an appropriate level.

However, Examples 1 to 3 are examples of the above-mentioned examples. When the average temperature in the reactor where the hydrogenation of the phthalate compound occurs is controlled within the range of 125°C to 160°C, while the highest in the reactor is- The minimum temperature difference (Δt) is controlled within the range of 4.5°C to 9.0°C, so that when the reaction occurs uniformly in the entire reactor, a product with an aromaticity of 2.5% to 5.5% can be obtained, which has low viscosity and low surface migration , And the loss of volatile matter is within the appropriate range.

More specifically, the factors corresponding to the aromaticity of the hydrogenated product can be controlled by changing the average temperature or the maximum-minimum temperature difference in the reactor, or both, to fall within the above-mentioned range. In particular, by sensitively adjusting the reaction conditions so that the relationship between the average temperature and the maximum-minimum temperature difference conforms to Equation 2, a product with ideal physical properties can be prepared.

a, b: heat exchanger c: reactor d: Gas-liquid separator 1,2: Gas phase raw materials 3, 4: Liquid phase raw materials 5: reaction mixture 6: Unreacted gas phase raw materials 7: Liquid phase reaction product

Fig. 1 is a schematic diagram of a hydrogenation reaction apparatus used in the hydrogenation method of the present invention.

a, b: heat exchanger

c: reactor

d: Gas-liquid separator

1,2: Gas phase raw materials

3, 4: Liquid phase raw materials

5: reaction mixture

6: Unreacted gas phase raw materials

7: Liquid phase reaction product

Claims (16)

A method for hydrogenating a phthalate compound includes a step of reacting a phthalate compound with hydrogen in a reactor in the presence of a hydrogenation catalyst. In the reaction process, the reaction The average temperature in the reactor is controlled within the range of 125°C to 160°C, while the maximum-minimum temperature difference in the reactor is controlled within the range of 4.5°C to 9.0°C, thereby obtaining a 2.5% to 5.5% according to the following equation 1. The aromatic hydrogenation products: [Equation 1] Aromaticity (%) = 100*(B/A) In Equation 1, A and B respectively represent the measured value of the hydrogen nuclear magnetic resonance spectroscopy (H-NMR) of the hydrogenated product, where A represents the total number of hydrogen atoms included in the hydrogenated product, and B represents the hydrogenated product The number of hydrogen atoms contained in the aromatic functional group. The hydrogenation method according to claim 1, wherein during the reaction, the average temperature and the maximum-minimum temperature difference in the reactor conform to the relationship of the following equation 2: [Equation 2] 0.13*T-12.3 ≤ Δt ≤ 0.13*T-10.3 In Equation 2, T represents the average temperature (°C) in the reactor during the reaction; and Δt represents the difference (°C) between the highest temperature and the lowest temperature in the reactor during the reaction. The hydrogenation method according to claim 1, wherein during the reaction, the average temperature in the reactor is controlled to be in the range of 130°C to 155°C. The hydrogenation method according to claim 1, wherein during the reaction process, the maximum-minimum temperature difference in the reactor is controlled within the range of 5.1°C to 7.9°C. The hydrogenation method according to claim 1, wherein the hydrogenated product having an aromaticity of 3.0% to 5.0% according to Equation 1 is obtained. The hydrogenation method according to claim 1, wherein during the reaction, the reaction amount per unit volume (m ³ ) of the reactor is 20 kmol/h or less. The hydrogenation method according to claim 1, wherein a cooling member is installed outside the reactor through a refrigerant (refrigerant) circulation. The hydrogenation method according to claim 1, wherein the ^{mass flux per unit area (m 2} ) of the phthalate compound injected into the reactor is 10000 kg*hr ^-1 *m ^-2 to 15000 kg*hr ^-1 *m ^-2 . The hydrogenation method according to claim 1, wherein the amount of hydrogen injected into the reactor is 3 mol to 300 mol based on 1 mol of the phthalate compound. The hydrogenation method according to claim 1, wherein the phthalate compound is selected from the group consisting of phthalate (phthalate), terephthalate (terephthalate), isophthalate (isophthalate) And one or more of the group consisting of one of the aforementioned carboxylic acid compounds. The hydrogenation method according to claim 1, wherein the gas phase raw material is passed into the upper or lower part of the reactor, and the liquid phase raw material is passed into the upper part of the reactor. The hydrogenation method according to claim 1, wherein the hydrogenation catalyst is selected from the group consisting of ruthenium (Ru), palladium (Pd), rhodium (rhodium, Rh) and platinum (platinum, Pt) One or more of the group. The hydrogenation method according to claim 1, wherein the hydrogenation catalyst is used in an amount of 3% by weight or less based on 100% by weight of the support. A hydrogenated phthalate compound or hydrogenated terephthalate compound prepared by the hydrogenation method of any one of claims 1 to 13. A plasticizer comprising the hydrogenated phthalate compound or hydrogenated terephthalate compound described in claim 14. A resin composition, comprising the plasticizer described in claim 15; and selected from the group consisting of ethylene vinyl acetate, polyethylene, polypropylene, polyvinyl chloride (polyvinyl chloride), A resin in the group consisting of polystyrene, polyurethane, polybutadiene, silicone, thermoplastic elastomer and the above-mentioned copolymer.

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