RU2796601C2 - Method for producing carbonate esters and catalytic structure for producing carbonate esters - Google Patents

Abstract

FIELD: carbonate ester production.

SUBSTANCE: invention relates to a method for producing a carbonate ester, which includes the step of allowing monohydric alcohol and carbon dioxide to interact with each other in the presence of a catalytic structure and a hydration agent to form a carbonate ester. While the catalytic structure contains the base material and the catalytic layer formed on at least part of the surface of the base material, and containing a solid catalyst and an inorganic binder; the solid catalyst contains cerium oxide; the amount of solid catalyst based is from 15 to 200 g/m²; and the inorganic binder contains silicon dioxide and/or alumina. The invention also relates to a catalytic structure, a device for producing an ester, as well as a method for producing a carbonate ester.

EFFECT: catalyst used allows a highly efficient carbonate ester production reaction to be carried out for a long time.

19 cl, 8 dwg, 4 tbl

Description

FIELD OF TECHNOLOGY

[0001]

The present invention relates to a process for producing a carbonate ester and to a catalytic structure for producing a carbonate ester.

BACKGROUND OF THE INVENTION

[0002]

Currently, the problem of global warming is of concern. COP (Conference of the Parties) advocates discussion of international schemes such as reducing greenhouse gas emissions, setting long-term global targets such as staying well below average temperature rise of 2°C above pre-industrial levels and peaking emissions as soon as possible , to dramatically reduce emissions based on the latest scientific knowledge. Although the Paris Agreement reached at COP21 commits all nations to make efforts to develop and share information on long-term development strategies with low greenhouse gas emissions, our country has developed an 80% reduction in greenhouse gas emissions by 2050 as a long-term goal. Carbon dioxide is believed to have the largest impact of all man-made greenhouse gas emissions, so stakeholders are working hard to develop technological countermeasures to reduce carbon dioxide emissions. Although attempts have been made to convert emitted carbon dioxide into a useful substance as a technological countermeasure, a large amount of energy is required to convert carbon dioxide into another substance, and therefore it is desirable to develop an effective catalyst to accelerate the reaction. In addition, the beneficial substance must be highly sought-after substance in order to be adapted to a technique that contributes to the reduction of carbon dioxide emissions.

[0003]

However, carbonate esters are very useful compounds that can be used as additives such as gasoline octane additive, diesel fuel additive to reduce exhaust particulates, and as an alkylating agent, carbonylating agent, solvent. or similar materials for the synthesis of a resin or an organic compound such as polycarbonate, urethane, a pharmaceutical agent, an agrochemical or lithium battery electrolyte, a lubricant raw material, or an oxygen scavenger raw material for rust prevention in steam boiler pipes.

[0004]

A carbonate ester is the general name for a compound obtained by replacing one or two of the two hydrogen atoms in carbonic acid, CO(OH) ₂ , with an alkyl group or an aryl group, having the structure RO-C(=O)-OR' (where R and R' is a saturated hydrocarbon group or an unsaturated hydrocarbon group). Therefore, if such a compound can be effectively produced from carbon dioxide, which is a compound equivalent to carbonic acid, it may be useful to reduce carbon dioxide emissions.

[0005]

When the carbonate ester is directly synthesized from carbon dioxide and liquid alcohol, the reaction is known to be accelerated in the presence of a solid catalyst such as cerium oxide (CeO ₂ ) powder or zinc oxide (ZrO ₂ ) powder and a nitrile compound as a hydration agent. . In particular, when cerium oxide powder is used as the solid catalyst, it is known that the reaction proceeds faster (for example, see Patent Document 1).

[0006]

Several well-known examples of using a catalyst in a solution reaction system by attaching a catalyst to a catalyst support structure aim to increase the feed solution feed rate or to prevent the catalyst from being washed out of the feed (eg, see Patent Documents 2-5). In these examples, techniques such as metal plating, spraying, vapor deposition, or liquid plating are used to secure the catalyst to the catalyst support structure.

PRIOR ART DOCUMENT

PATENT DOCUMENT

[0007]

Patent Document 1: Japanese Published Unexamined Patent Application No. 2012-162523

Patent Document 2: Japanese Published Unexamined Patent Application No. H6-145113

Patent Document 3: International Published Patent Application WO2016/093329

Patent Document 4: Japanese Published Unexamined Patent Application No. 2013-646

Patent Document 5: Japanese Published Unexamined Patent Application No. 2016-59901

BRIEF DESCRIPTION OF THE INVENTION

PROBLEMS SOLVED BY THE INVENTION

[0008]

When the authors of the present invention tested the described methods, they encountered the problem of the vulnerability of cerium oxide to grinding during the reaction. Since the cerium oxide powder directly used in the reaction is pulverized due to cracks caused by contact between the powder particles or between the powder and the reactor wall, it is difficult to separate the powder from a product such as a carbonate ester. In addition, if cerium oxide is directly charged to the reactor, the reaction substrate fluid causes unevenness in the reaction vessel, which makes it difficult to achieve high reaction efficiency when the reaction proceeds at such a high flow rate as is necessary for industrial processes.

[0009]

Therefore, in order to prevent grinding of the cerium oxide powder during the reaction, the present inventors have experienced the use of a catalyst structure in which a catalyst containing cerium oxide is fixed with a base material (catalyst-supporting structure) such as a honeycomb in the reaction system. According to the methods described in Patent Documents 2 to 5, the catalyst was fixed on the base material with a layer of not more than 5 to 10 µm.

In addition, when cerium oxide is applied to the base material by the methods described in Patent Documents 2 to 5, it has been found that it is difficult to further improve the reaction efficiency because the amount of catalyst fixed per unit area of the base material determines the reaction rate. In addition, if a large amount of catalyst is applied to the base material, the catalyst may fall off or may be separated from the base material.

[0010]

Therefore, the present invention has been made in view of the above problems, and its object is to provide a method for producing a carbonate ester in which, by using a catalyst structure having a sufficient amount of a cerium oxide-containing solid catalyst supported on a base material, grinding and separation of the solid catalyst can be suppressed. , and which can provide a highly efficient carbonate ester production reaction for a long time. Further, it is also an object of the present invention to provide a carbonate ester catalyst structure that can be subjected to a regenerating treatment such as a heat treatment or the like to restore its function even if its catalytic activity has deteriorated after a long period of exposure to the reaction conditions, and therefore, which can be easily applied continuously for a long time.

PROBLEM SOLVING TOOLS

[0011]

In the course of extensive research to solve the above problems, the present inventors have studied methods for attaching a solid catalyst to a base material, and found that a relatively large amount of solid catalyst can be attached to the base material relatively firmly when the solid catalyst is attached to the base material together with an inorganic binder containing an oxide. aluminum and/or silicon dioxide. They also found that the activity of the solid catalyst was sufficiently maintained when an inorganic binder was used to fix the solid catalyst. As a result of additional research based on these discoveries, the authors have carried out the present invention.

The essence of the present invention is as follows:

[0012]

(1) A process for producing a carbonate ester, comprising the step of allowing a monohydric alcohol and carbon dioxide to react with each other in the presence of a catalytic structure and a hydration agent to form a carbonate ester, wherein:

the catalytic structure comprises a base material and a catalytic layer formed on at least a portion of the surface of the base material and containing a solid catalyst and an inorganic binder;

the solid catalyst contains cerium oxide;

the amount of applied solid catalyst is from 15 g/m ² to 200 g/m ² ; And

the inorganic binder contains alumina and/or silicon dioxide.

(2) The method for producing a carbonate ester according to (1), characterized in that the inorganic binder contains silica.

(3) The method for producing a carbonate ester according to any one of paragraphs. (1) or (2), characterized in that the catalytic structure further comprises an intermediate layer consisting of an inorganic binder formed between the catalytic layer and the base material.

(4) The method for producing a carbonate ester according to any one of paragraphs. (1) - (3), in which the amount of supported solid catalyst in the catalytic layer is from 15 g/m ² to 150 g/m ² .

(5) The method for producing a carbonate ester according to any one of paragraphs. (1) - (3), in which the amount of supported solid catalyst in the catalytic layer is from 15 g/m ² to 70 g/m ² .

(6) The method for producing a carbonate ester according to any one of paragraphs. (1) to (5), wherein the base material contains through holes that serve as passageways for monohydric alcohol and carbon dioxide, and

the catalytic layer is formed on the surface of said through holes.

(7) The method for producing a carbonate ester according to any one of paragraphs. (1) to (6), wherein the solid catalyst further contains an oxide of a rare earth element.

(8) The carbonate ester production method according to (7), wherein the solid catalyst contains lanthanum oxide.

(9) The method for producing a carbonate ester according to any one of paragraphs. (1) - (8), in which the average thickness of the catalytic layer is 12 μm - 150 μm.

(10) The method for producing a carbonate ester according to any one of paragraphs. (1) - (9), in which the base material is a metal honeycomb.

(11) The method for producing a carbonate ester according to any one of paragraphs. (1) - (10), in which the hydration agent contains a nitrile compound.

(12) The method for producing a carbonate ester according to any one of paragraphs. (1) - (11), in which the hydration agent contains 2-cyanopyridine.

(13) A carbonate ester catalytic structure, comprising:

base material; And

a catalytic layer formed on at least a part of the surface of the base material and containing a solid catalyst and an inorganic binder,

Where:

the solid catalyst contains cerium oxide;

the amount of applied solid catalyst is from 15 g/m ² to 200 g/m ² ; And

the inorganic binder contains silicon dioxide and/or alumina.

(14) The carbonate ester catalyst structure according to (13), wherein the amount of supported solid catalyst is 15 g/m ² to 150 g/m ² .

(15) An apparatus for producing a carbonate ester, comprising:

a catalytic structure for producing a carbonate ester according to any one of paragraphs. (13) or (14); And

an introduction route for feeding at least a monohydric alcohol and carbon dioxide into the catalytic structure.

(16) The carbonate ester producing apparatus according to (15), further comprising a discharge path through which the carbonate ester produced from monohydric alcohol and carbon dioxide is discharged.

(17) An apparatus for producing a carbonate ester according to any one of paragraphs. (15) or (16), in which a plurality of catalytic structures are arranged in one line.

(18) An apparatus for producing a carbonate ester according to any one of paragraphs. (15) or (16), containing an integrated structure, including a plurality of parallel catalytic structures.

(19) A method for producing a carbonate ester, comprising the step of circulating a reaction substrate containing a monohydric alcohol and carbon dioxide through a carbonate ester producing apparatus according to any one of paragraphs. (15) - (18) with space velocity (per minute) from 0.005 to 5000.

EFFECTS OF THE INVENTION

[0013]

The present invention provides a process for producing a carbonate ester and a catalyst structure for producing a carbonate ester, wherein the catalyst structure containing a sufficient amount of a cerium oxide-containing solid catalyst placed on a base material can suppress grinding and separation of the solid catalyst, and can achieve a highly efficient carbonate complex production reaction. ether.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]

[Figure 1] Partially enlarged cross-section showing a catalytic structure for producing a carbonate ester according to one embodiment of the present invention.

[Figure 2] Partially enlarged cross-section showing a catalytic structure for producing a carbonate ester according to another embodiment of the present invention.

[Figure 3] Graph showing carbonate ester production reaction yields (changes in catalytic activity retention rates) using a carbonate ester production catalyst design according to one embodiment of the present invention and the catalyst design used for comparison.

[Figure 4] Side view showing a specific example of a carbonate ester apparatus containing catalyst structures.

[Figure 5] Top view (A) and bottom view (B) showing a carbonate ester making apparatus containing catalyst structures.

[Figure 6] Schematic representations showing one example of the shape of a carbonate ester apparatus containing catalyst constructs suitable for industrial scale applications.

[Figure 7] Views showing specific examples of the honeycomb-like base material (metal honeycomb) used in the carbonate ester making apparatus, which has a cylindrical outer shape (Figure 7(A)) and a rectangular parallelepiped outer shape (Figure 7(B)) , respectively.

[Figure 8] A diagram schematically showing a specific example of a carbonate ester production equipment, including an apparatus such as a carbonate ester production apparatus and the like.

MODES FOR IMPLEMENTING THE INVENTION

[0015]

Below, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Components having substantially the same functional configurations are identified by the same reference numerals in the description and figures in order to avoid duplicate explanations. In addition, the components in the figures are highlighted for convenience, and the aspect ratios and sizes of the components in the figures do not represent the actual aspect ratios and sizes of the components.

[0016]

<1. Catalyst Design for Carbonate Ester Production>

First, a preferred embodiment of the catalytic design for producing the carbonate ester of the present invention will be described. Figure 1 is a partially enlarged cross-section of a carbonate ester catalyst structure according to this embodiment. The catalytic structure for producing carbonate ester 1 according to this embodiment (hereinafter simply "catalyst structure") catalyzes the formation of a carbonate ester from carbon dioxide and a monohydric alcohol in the presence of a hydration agent.

[0017]

The catalyst structure for producing carbonate ester 1 according to this embodiment comprises a base material 10 and a catalyst layer 20 formed on at least a portion of the surface of the base material 10, which contains a solid catalyst 40 and an inorganic binder 50, where: the solid catalyst 40 contains cerium oxide ; the amount of solid catalyst 40 based on the catalyst layer 20 is 15 g/m ² to 200 g/m ² ; and inorganic binder 50 contains silicon dioxide and/or alumina. Further, in this embodiment, the carbonate ester catalyst structure 1 is provided with an intermediate layer 30 containing an inorganic binder 50 between the catalyst layer 20 and the base material 10.

[0018]

(1.1. Base material)

The base material 10 is a catalyst-supporting structure for supporting the solid catalyst 40. Therefore, the solid catalyst 40 can be attached to the surface of the base material 10 so that uneven distribution of the solid catalyst 40 in the reaction vessel during the reaction can be eliminated, and local variations can be reduced. temperatures in the reaction vessel due to the heat generated during the reaction, compared with the direct use of a powdered catalyst. Therefore, according to this embodiment, the product can be synthesized in a high efficiency mode.

In addition, the catalyst structure for producing carbonate ester 1 can be removed from the reaction vessel and then subjected to a regeneration treatment such as heat treatment or the like to restore its function even if the activity of the solid catalyst 40 is reduced after a long period of continuous reaction, and therefore can be easily used for a long period of time. In addition, as will be described in detail, the components of the solid catalyst 40 can be adjusted to maintain excellent catalytic function and reduce the frequency of regeneration treatment.

[0019]

The base material 10 is not particularly limited as long as it allows the formation of the catalyst layer 20 containing the solid catalyst 40 and may be of any shape and size. In particular, the base material 10 preferably has through holes that serve as passageways for the monohydric alcohol and carbon dioxide. Since the base material 10 has through holes, the diffusion efficiency of the raw material, i. e. monohydric alcohol and carbon dioxide can be increased, and products such as carbonate ester and by-product water can be easily collected. In addition, the catalyst layer 20 is provided on the surface of the through holes, so that the area of the catalyst layer 20 in contact with the feedstock can be increased, i. monohydric alcohol and carbon dioxide, to increase the efficiency of the carbonate ester production reaction.

[0020]

The base material 10 may have a porous shape such as a foam shape, a honeycomb shape (solid shape), a net shape, a column shape, a cylindrical shape, or the like. In particular, the base material 10 preferably has a porous shape, a foam shape, a honeycomb shape, or a mesh shape. Since said molds can be provided with through holes, the above-described advantages of providing through holes can be advantageously obtained. In particular, when the base material 10 has a honeycomb shape, the specific surface area of the through holes can be relatively large while increasing the physical strength of the base material 10 and the shape stability of the base material 10.

[0021]

Although the cross-sectional shape of the through hole in the honeycomb structure is not particularly limited, it may be a polygonal shape such as a triangle, a quadrangle, or a hexagon, or any waveform such as a sine wave (fin shape).

[0022]

Although the size of the through holes in the base material 10 is not particularly limited, it is, for example, 0.3 to 6 mm, and preferably 0.5 to 5 mm. Similarly, although the number of through holes (number of cells) in the base material 10 is not particularly limited, it can be, for example, 25 - 1200 cells / inch ² (3.9 - 186 cells / cm ² ) and preferably 100 - 600 cells / inch ² (15.5 - 93 cells/cm ² ).

[0023]

In addition, the material constituting the material of the base 10 is not particularly limited and may be a metal material such as stainless steel or aluminum steel, or any ceramic material such as cordierite, mullite, silicon carbide, alumina, silicon dioxide, titanium, zirconia or cerium dioxide.

[0024]

The base material 10 is a honeycomb-like base material composed of a metal material or a ceramic, namely a ceramic honeycomb or a metal honeycomb, and a metal honeycomb is particularly preferred. A metal material such as stainless steel (martensitic, ferritic, austenitic, austenitic-ferritic duplex or precipitation hardened steel) can be used as the material of the base 10 to improve the thermal conductivity of the base material 10. As a result, the heat generated in the reaction can be easily removed from of the reaction vessel along with the movement of the raw material to maintain a substantially uniform temperature in the catalyst vessel, thereby enabling the catalyst layer 20 to stably exhibit high catalytic activity for a long time. Alternatively, if ceramics are used to form the base material 10, the adhesion of the catalyst layer 20 to the base material 10 can be further improved. A specific example of a metal honeycomb without a catalyst layer is shown in Figure 6.

[0025]

(1.2. Catalytic bed)

The catalytic layer 20 is formed on at least a portion of the surface of the base material 10 through an intermediate layer 30, which will be described later. However, as will be described in detail, the catalyst layer 20 may also be located directly on the surface of the base material 10.

In general, the catalyst layer 20 is formed on the inner wall of the through holes of the base material 10. The catalyst layer 20 contains a solid catalyst 40 containing cerium oxide and catalyses the reaction of producing a carbonate ester from carbon dioxide and a monohydric alcohol.

[0026]

Catalytic layer 20, solid catalyst 40 contains at least cerium oxide. Cerium oxide has excellent catalytic activity in the reaction of producing a carbonate ester from carbon dioxide and a monohydric alcohol. However, since cerium oxide is generally vulnerable to pulverization, the cerium oxide in this embodiment is firmly attached to the base material 10 by the inorganic binder 50 to be described below, thereby suppressing separation and preventing pulverization.

[0027]

Solid catalyst 40 may further contain one or more types of catalysts in addition to cerium oxide. As such a catalyst, any catalyst capable of catalyzing the reaction between carbon dioxide and a monohydric alcohol can be used, examples include a tin compound, a thallium compound, a nickel compound, a vanadium compound, a copper compound, an alkali metal carbonate, zirconium oxide, titanium oxide, and a rare earth element (in in particular, an oxide of a rare earth element) in addition to cerium. Of these, zirconium oxide is preferred because it has a high catalytic activity. In this case, the proportion of cerium oxide in the solid catalyst 40 is, for example, 5 atomic percent (at.%) or more, and preferably 20 at.% or more. In addition, the proportion of cerium oxide in the solid catalyst 40 may be 100 at.%.

[0028]

If the cerium oxide catalyst is continuously used for the carbonate ester direct synthesis reaction, the catalytic activity decreases with time, and therefore, regeneration treatment of the catalyst may be required quite often. However, high catalytic activity can be maintained by adjusting the catalyst components. For example, by adding rare earth elements other than cerium as a co-catalyst component, the catalytic activity of the solid catalyst 40 is likely to remain high in the carbonate ester production reaction for a longer time.

Examples of rare earth elements other than cerium include scandium, yttrium, lanthanum, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. Of the rare earth elements, lanthanum, praseodymium or gadolinium are preferably introduced into the solid catalyst 40, and the use of lanthanum is particularly advantageous. The metal element contained in the solid catalyst 40 or present in the outer layer of the solid catalyst 40 is mainly an oxide.

[0029]

The proportion of the co-catalytic component, for example rare earth oxide, in the solid catalyst 40 is preferably 0.01 to 10 wt. %, more preferably 0.05 - 5.0 wt. %, even more preferably, 0.1 - 2.5 wt. % and especially preferably 0.2 - 2.0 wt. %, for example, 1 wt. %, based on the total weight of the solid catalyst.

[0030]

In addition, the amount of solid catalyst 40 contained in the catalyst layer 20 is 15 g/m ² to 200 g/m ² . Therefore, the efficiency of the reaction catalyzed by the catalytic structure 1 can be increased. On the other hand, if the amount of supported solid catalyst 40 is less than 15 g/m ² , the efficiency of the reaction catalyzed by the catalyst structure 1 may be insufficient. In addition, if the amount of the supported solid catalyst 40 exceeds 200 g/m ² , the raw substrate may diffuse into the deep part of the catalyst layer 20 and become a hindrance, which, on the contrary, deteriorates the reaction efficiency. The present inventors have found that the amount of solid catalyst 40 and the reaction efficiency are not in a simple positive correlation, but in the appropriate range, the amount of solid catalyst 40 provides high reaction efficiency. Since such a relatively large amount of solid catalyst 40 can be supported on the catalyst structure 1, the activity can be maintained high even at a high feed rate, and the reactor size can be relatively small to reduce plant cost.

[0031]

From the viewpoint of increasing the efficiency of the reaction catalyzed by the catalytic structure 1, the amount of solid catalyst 40 in the catalytic layer 20 is, for example, 10 g/m ² to 200 g/m ² , preferably 15 g/m ² to 150 g/ m ² , more preferably from 15 g/m ² to 70 g/m ² and even more preferably from 15 g/m ² to 30 g/m ² .

Similarly, from the viewpoint of increasing the efficiency of the reaction catalyzed by the catalytic structure 1, the amount of cerium oxide present in the catalytic layer 20 is, for example, 10 g/m ² to 200 g/m ² , preferably 15 g/m ² to 150 g/m ² , more preferably 15 g/m ² to 70 g/m ² , and even more preferably 15 g/m ² to 30 g/m ² .

[0032]

The solid catalyst 40 is applied in an amount in the above range, the thickness of the catalyst layer 20 averages about 12 µm to 150 µm, which is significantly greater than the thickness of the catalyst layer formed by the methods described in Patent Documents 2 to 5 (which is at best about 5 µm ). Traditionally, it has been difficult to apply such a large amount of solid catalyst 40 without suppressing its reactivity, in this embodiment, this problem is solved by using an inorganic binder 50, which will be described below. The average thickness of the catalytic layer 20 may be about 12 µm - 180 µm and preferably about 15 µm - 150 µm.

[0033]

In addition, the thickness of the catalyst layer 20 formed in the through holes of the base material 10 depends on the shape of the through holes and is not necessarily uniform. A uniform catalyst layer can be formed on a flat surface using a doctor blade method or the like to obtain a correlation between the amount of solid catalyst in the catalyst layer and the thickness of the catalyst layer, so that even when through holes are formed, the average thickness of the catalyst layer 20 on the base material 10 can be determined from from the mass of solid catalyst 40 based on how the apparent thickness. In the present description, the (average) thickness of the catalytic layer 20 has always been determined according to the specified method.

[0034]

In addition, although the average particle size used in the preparation of the solid catalyst 40 is not particularly limited, it is, for example, 0.001 µm to 100 µm, preferably 0.005 µm to 100 µm, more preferably 0.01 µm to 80 µm, even more preferably 0.1 µm to 60 µm, particularly preferably 1.0 µm to 30 µm, and most preferably 3.0 µm to 15 µm. Therefore, the specific surface area of the solid catalyst 40 can be relatively large to improve the reaction catalysis efficiency, and the separation of the solid catalyst 40 is prevented by the inorganic binder 50.

[0035]

Here, "average particle size" refers to 50% of the particle size distribution by volume (D50) as measured by the laser diffraction/wet scattering method. When measurement by the laser diffraction/light scattering method is difficult due to poor dispersibility or the like, techniques such as scanning electron microscope observation, calculation from X-ray diffraction measurement data, an image analysis method, or the like can be applied.

[0036]

Moreover, in addition to the solid catalyst 40 described above, the catalyst layer 20 also contains an inorganic binder 50 for attaching the solid catalyst 40. The inorganic binder 50 contains silica and/or alumina. As a result of extensive research, the inventors of the present invention have found that when silica and/or alumina are used as the inorganic binder 50, the solid catalyst 40 can be present in a relatively large amount without suppressing the catalytic activity of the solid catalyst 40. Such an inorganic binder 50 allows tight attachment of the solid catalyst 40 containing cerium oxide to the base material 10, and suppressing separation or falling off of the solid catalyst 40 during the reaction. As a result, the catalyst structure 1 can be used for a long time while maintaining its high activity. In addition, an inorganic binder can be used to maintain adhesion between the catalyst layer 20 and the base material 10 without destroying the catalyst layer 20 even if the temperature of the reaction or regeneration treatment becomes relatively high.

[0037]

The silica and alumina that may be contained in the inorganic binder 50 are not particularly limited, and may be any silica and alumina obtained using a suitable compound as a precursor. These silica and alumina may be amorphous or crystalline.

[0038]

The inorganic binder 50 may further comprise a component in addition to silica and alumina. Examples of such a component include magnesium, calcium, and impurities that may enter the mixture during the preparation of the inorganic binder 50. In addition, the proportion of the total amount of silicon dioxide and alumina in the inorganic binder 50 is preferably 20 wt. % or more, and more preferably, 50 wt. % or more. Even more preferably, the inorganic binder 50 consists essentially of silica and/or alumina, and particularly preferably consists of silica and/or alumina.

[0039]

In addition, silica and alumina usually exist as an assembly (agglomerate) of fine particles in the inorganic binder 50, so the inorganic binder 50 is porous. Because the inorganic binder 50 is porous, the raw material, i. carbon dioxide and monohydric alcohol can reach the surface of the solid catalyst 40 that is not on the surface of the catalyst layer 20.

[0040]

Although the specific surface area of the solid particles of the inorganic binder 50 is not particularly limited, it may be, for example, 1 m ² /g to 1000 m ² /g, and preferably 10 m ² /g to 500 m ² /g. of the inorganic binder 50 is in the above range, the rate of diffusion of carbon dioxide and monohydric alcohol into the inorganic binder 50 will be fast enough to accelerate the reaction on the surface of the solid catalyst 40, and the solid catalyst 40 can be more closely attached to the catalyst layer 20. The specific surface area can be measured at using the BET method.

[0041]

The amount of the solid component in the inorganic binder 50 present in the catalyst layer 20 is, for example, 1 g/m ² to 100 g/m ² , and more preferably 1 g/m ² to 40 g/m ² . Therefore, the exposed surface of the solid catalyst 40 can be made large in order to improve the efficiency of the reaction as well as to firmly attach the solid catalyst 40 to the base material 10.

[0042]

In addition, the solid component of the inorganic binder 50 is contained in the catalyst layer 20 in a proportion of, for example, 0.01 g to 5 g, preferably 0.10 g to 1.0 g per 1 g of solid catalyst. Therefore, the exposed surface of the solid catalyst 40 can be made large in order to improve the efficiency of the reaction as well as to firmly attach the solid catalyst 40 to the base material 10.

[0043]

The solid component contained in the inorganic binder 50 refers to the inorganic oxide particles intentionally introduced into the binder and the cured material in the binder. The weight ratio of the solid component in the inorganic binder can be determined by dividing the weight remaining after drying and curing of the inorganic binder alone by the weight of the inorganic binder before drying and curing. That is, the weight of the solid component of the inorganic binder can be calculated as (mass ratio of the solid component) x (weight of applied inorganic binder).

[0044]

(1.3 Intermediate layer)

The intermediate layer 30 is a layer composed of an inorganic binder 50 located between the base material 10 and the catalyst layer 20. Therefore, an intermediate layer 30 composed of an inorganic binder 50 can be formed between the catalyst layer 20 containing the solid catalyst 40 and the material substrate 10, whereby the adhesion of the catalyst layer 20 to the substrate material 10 can be further enhanced, which prevents the solid catalyst 40 from separating from the catalyst structure 1. In addition, such an intermediate layer 30 can be provided to achieve adequate adhesion between the catalyst layer 20 and the substrate material 10 even if the base material 10 used is inherently poor in adhesion to the catalyst layer 20.

[0045]

Since the inorganic binder component 50 may be the same as in the catalyst layer 20 described above, its description will be omitted. However, the inorganic binder 50 in the catalyst layer 20 and the inorganic binder in the intermediate layer 30 may be the same or different in terms of their composition.

[0046]

In addition, the amount of the solid component in the inorganic binder 50 in the intermediate layer 30 is, for example, 1 g/m ² to 100 g/m ² , and more preferably 10 g/m ² to 50 g/m ² . Within this range, the adhesion between the catalyst layer 20 and the base material 10 can be further improved while preventing cohesive failure of the intermediate layer 30.

[0047]

In the described catalyst structure for producing carbonate ester 1 according to this embodiment, a relatively large amount of solid catalyst 40 is firmly attached in the catalyst layer 20 with an inorganic binder 50 containing silica and/or alumina. In addition, the inorganic binder 50 does not suppress the catalysis of the reaction by the solid catalyst 40. As a result, if the carbonate ester production catalyst structure 1 is used to produce a carbonate ester, the efficiency of the carbonate ester production reaction can be improved. In addition, since the solid catalyst 40 is firmly attached to the base material 10 by the inorganic binder 50, the solid catalyst 40 can be prevented from separating from the catalyst structure to produce the carbonate ester 1, and hence the solid catalyst 40 can be prevented from being crushed.

[0048]

With such a catalytic structure for producing carbonate ester 1, high reaction efficiency can be achieved even when carrying out the reaction at such a high flow rate as is required in an industrial process. In addition, since separation and pulverization of the solid catalyst 40 can be prevented, it is highly durable and can be reused even in the corrosive environment required in the industrial process.

[0049]

A catalytic design for producing carbonate ester 1 according to this embodiment has been described, but the present invention is not limited to this embodiment. Figure 2 is a partially enlarged cross section of a carbonate ester catalyst structure according to another embodiment of the present invention. In the catalyst structure for producing carbonate ester 1A shown in Figure 2, the catalyst layer 20 is provided on the base material 10. Unlike the above-described catalyst structure for producing carbonate ester 1, an intermediate layer consisting of an inorganic binder 50 is omitted. Even if the intermediate layer is excluded, as in this case, the solid catalyst 40 in the catalytic layer 20 is successfully attached by an inorganic binder 50 containing silica and/or alumina, thereby preventing the solid catalyst 40 from separating from the catalyst structure to produce carbonate ester 1A and associated with him grinding the solid catalyst 40.

[0050]

The relationship between the catalytic layer 20 and the intermediate layer 30 can be observed by elemental analysis or the like, such as using an optical microscope, a scanning electron microscope, an EMF (Energy Dispersive X-ray Spectrometer) or the like.

[0051]

In addition, the proportion of the metal component (for example, cerium) present in the catalyst layer 20 can be determined using elemental analysis in order to calculate the amount of solid catalyst 40 deposited in the catalyst layer 20 based on the area of the catalyst layer and the total weight of the supported catalyst. layer 20. More specifically, when the component of the solid catalyst 40 is cerium oxide, it can be calculated according to the following equation.

[0052]

(amount of solid catalyst on the basis)=[(mass of catalytic layer) x (mass fraction of cerium in the catalytic layer) x ((mass of cerium oxide)/(mass of cerium))]/(area of catalytic layer)

[0053]

This value is equal to the weight of the solid catalyst 40 per unit area of the base material 10 on which the solid catalyst 40 is located and can be determined regardless of the presence of the intermediate layer 30.

[0054]

Scanning high-frequency inductively coupled plasma (ICP) can be used as an elemental analysis method to identify a metal component. The amount of inorganic binder 50 present in catalyst layer 20 or intermediate layer 30 can similarly be determined by calculating the ratio of the solid component contained in the inorganic binder used to form catalyst layer 20 or intermediate layer 30, based on the proportion of the metal component determined using the above elemental analysis. Here, the area of the catalytic layer refers to the area deposited (formed) by the solid catalyst 40 (catalyst layer 20). For example, if the base material 10 is honeycomb-shaped and the catalyst layer 20 is not applied to the outer periphery, the area of the catalyst layer refers to the entire surface area forming through holes within the base material 10 on which the catalyst layer 20 is applied. 30, the amount of supported solid catalyst 40 can be determined in a similar manner.

[0055]

<2. Process for Producing a Catalyst Structure for Producing Carbonate Ester>

The method for producing the carbonate ester catalyst structure according to this embodiment will be described in detail below by illustrating the method for producing the carbonate ester catalyst structure 1.

[0056]

First, a binder mother liquor is prepared to create an intermediate layer 30. A binder mother liquor can be prepared by dissolving or dispersing an inorganic binder material 50, such as alumina, silica, or a precursor thereof, in a suitable liquid medium such as water or alcohol. of the binder 50 in the mother liquor is not particularly limited, and can be appropriately determined according to the method of applying the binder mother liquor to the base material 10.

[0057]

Then, the base material 10 is prepared by forming an intermediate layer 30 thereon. More specifically, the binder mother liquor is applied to the base material 10, dried, and cured. coater, Commabar dosing system coater, die coater, engraved roller coater, spin coater, slot coater or similar methods, inkjet, spray, dip or similar methods. In particular, if the base material 10 has through holes, immersion is preferred, namely, immersion of the base material 10 into the binder mother liquor. In order to increase the film thickness of the intermediate layer 30, the binder solution can be reapplied many times.

[0058]

Then, the binder mother liquor applied to the base material 10 is dried and cured to form the intermediate layer 30. The drying temperature may be any temperature that allows removal of the liquid medium, and may suitably be set according to the boiling point of the medium. For example, in the case of water, the temperature may be from 60°C to 100°C. In addition, the drying time can be set according to the dry state. The curing temperature can be set according to the curing temperature of the curing component in the binder. For example, in the case of a material based on siloxane, the curing temperature may be from 120°C to 200°C. The curing time is also not particularly limited and can be determined accordingly.

[0059]

The catalyst layer forming mixture is then prepared to form the catalyst layer 20. The catalyst layer forming mixture can be obtained by dissolving or dispersing the solid catalyst 40 and an inorganic binder material 50 such as alumina, silica or a precursor thereof in an appropriate liquid medium. such as water or alcohol.

[0060]

Then, a catalytic layer 20 is formed on the intermediate layer 30 deposited on the base material 10 or on the base material 10. More specifically, the mixture forming the catalyst layer is applied, dried and cured on the surface of the intermediate layer 30 or on the surface of the base material 10. The mixture forming catalytic layer, can be applied by any coating method, rod coater, blade coater, roller coater, coater with Commabar dosing system, die coater, engraved roller coater, coater by centrifugation, slotting or the like, inkjet printing, spraying, dipping or the like. In particular, if the base material 10 has through holes, immersion is preferred, namely, immersion of the base material 10 into the mixture forming the catalytic layer. In order to increase the film thickness of the catalyst layer 20, the mixture forming the catalyst layer can be reapplied many times.

[0061]

Then, the mixture forming the catalyst layer deposited on the base material 10 is dried and cured to form the catalyst layer 20. As a result, the catalyst structure 1 according to this embodiment can be obtained. The drying temperature may be any temperature capable of removing the liquid medium, and may suitably be set according to the boiling point of the medium. For example, in the case of water, the temperature may be from 60°C to 100°C. In addition, the drying time can be set according to the dry state. The curing temperature can be set according to the curing temperature of the curing component in the binder. For example, in the case of a material based on siloxane, the curing temperature may be from 120°C to 200°C. The curing time is also not particularly limited and can be determined accordingly.

[0062]

Adhesion at the interface between the surface of the base material 10 and the intermediate layer 30 or catalytic layer 20 may not be adequate. Therefore, before applying (creating) the intermediate layer 30 or the catalytic layer 20 directly onto the base material 10, the following pretreatment step is preferably carried out. More specifically, first, the base material is washed with a volatile organic solvent such as alcohol or acetone and dried to remove oil from the surface of the base material 10. Then, the base material 10 is immersed in an alkali aqueous solution, washed with water, and dried. an aqueous solution, washed with water, and dried. Alternatively, the base material 10 may be chemically treated, heat treated, plasma treated, UV treated, or corona treated.

[0063]

<3. Production method of carbonate ester>

The process for producing a carbonate ester using the above catalyst structure according to the preferred embodiment will be described below. The process for producing a carbonate ester according to this embodiment includes the step of allowing a monohydric alcohol and carbon dioxide to react to form a carbonate ester in the presence of the catalyst construct 1 described above and a hydration agent.

[0064]

Before describing the process for producing a carbonate ester according to said embodiment, let us describe the reaction mechanism in said method. First, catalytic structure 1 catalyzes the reaction between monohydric alcohol and carbon dioxide according to Formula (1) below.

[0065]

The solid catalyst 40 in catalyst design 1 is believed to have a catalysis mechanism involving dissociative adsorption of alcohol in the form of ROM (M is solid catalyst 40) and formation of RO-C (=O)-O...M with CO ₂ at the main point, and adsorption of the alcohol in the form of HO-R...M at the acid point, whereby both adsorbed compounds form RO-C(=O)-OR.

[0066]

Note that the reaction expressed by Formula (1) above is a reversible reaction. Therefore, in the presence of the resulting water, again reacting with the resulting carbonate ester, monohydric alcohol and carbon dioxide are again obtained. Therefore, a hydration agent is used to carry out the hydration reaction expressed by Formula (2) below to remove water generated as a by-product.

H ₂ O+R'CN=>R'C (=O)-NH ₂ (2)

[0067]

Since water is removed by the reaction expressed by Formula (2) above, the reverse reaction in Formula (1) is suppressed and the carbonate ester formation reaction is accelerated. For unknown reasons, the solid catalyst 40 also appears to have catalytic activity in the hydration reaction expressed by Formula (2) above. Here, the mechanism of the reaction proceeding in the method according to the present invention has been described.

[0068]

As described above, the process for producing a carbonate ester according to this embodiment includes the step of allowing a monohydric alcohol and carbon dioxide to react to form a carbonate ester in the presence of the above catalyst construct 1 and a hydration agent.

[0069]

More specifically, the catalyst structure 1 is provided in a reaction vessel, and a hydration agent, a monohydric alcohol, and carbon dioxide are introduced into said vessel, thereby allowing the carbonate ester production reaction to proceed.

[0070]

As the monohydric alcohol, one or more compounds selected from a primary alcohol, a secondary alcohol, and a tertiary alcohol can be used.

[0071]

More specifically, an example of a monohydric alcohol include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-pentyl alcohol, n-hexanol, 2-hexanol , 3-hexanol, heptanol, hexanol and phenol.

[0072]

The type of monohydric alcohol can be selected according to the chemical structure of the carbonate ester of interest and the manner in which the resulting carbonate ester is used.

[0073]

The hydration agent is not particularly limited, except that it must react with water and remove water, it may be a cyano group-containing compound as shown in Formula (2) above, one or more kinds of such compounds can be used alone or in combination. More specifically, examples include acetonitrile, cyanoethane, 1-cyanopropane, 2-cyanopropane, cyanoethylene, phenylacetonitrile, benzonitrile, 2-cyanopyridine, 2-cyanopyrazine, 2-cyanopyrimidine, thiophene-2-carbonitrile, and 2-fluonitrile (2-cyanofuran). In particular, 2-cyanopyridine is preferred in terms of water removal efficiency, i. e. rate of hydration reaction.

[0074]

The amount of hydration agent used can be determined based on the amount of monohydric alcohol used. For example, a hydration agent is used in an amount of 0.01 to 2 mol, and preferably 0.1 to 0.5 mol, per 1 mol of monohydric alcohol used.

[0075]

The reaction temperature for producing a carbonate ester is not particularly limited, and is preferably 50°C to 300°C. If the reaction temperature is lower than 50°C, the reaction rate may be slow depending on the reaction substrate, and both the carbonate ester synthesis reaction and the hydration agent hydration reaction are difficult to proceed, resulting in low productivity of the carbonate ester. On the other hand, if the reaction temperature exceeds 300° C., the rate of each reaction becomes high, but conversion into another monomer or polymerization of the carbonate ester and the amide monomer is likely, depending on the reaction substrate, and the yield of the carbonate ester becomes low. Even more preferably, the reaction temperature is from 100°C to 200°C. Since the reaction temperature is considered to vary depending on the kind and amount of the solid catalyst 40 and the amounts or ratios of the starting materials (monohydric alcohol, hydration agent), the optimum conditions are preferably determined as indicated.

[0076]

The reaction pressure is not particularly limited, and is preferably 0.1 MPa to 20 MPa (absolute pressure). If the reaction pressure is lower than 0.1 MPa (absolute pressure), a pressure reducing device is required, which not only complicates the equipment and increases the cost, but also requires energy to reduce the pressure, resulting in poor energy efficiency. On the other hand, if the reaction pressure exceeds 20 MPa, the hydration reaction of the hydration agent may be difficult to proceed depending on the kind of the hydration agent, which not only deteriorates the yield of the carbonate ester, but also requires energy to increase the pressure, resulting in poor energy efficiency. . From the viewpoint of increasing the yield of the carbonate ester, the reaction pressure is preferably 0.1 MPa to 10 MPa (absolute pressure).

[0077]

The reaction time is not particularly limited, and may be determined according to the kind of reaction substrate (raw material), the kind of hydrate, and the formation rate of the by-product, and is, for example, 5 minutes to 24 hours, preferably 15 minutes to 8 hours, and more more preferably, from 30 minutes to 6 hours. When using a continuous reactor, the total time elapsed from the introduction of material into the reaction vessel to the discharge of the resulting product from the vessel, taking into account the consumption of raw materials, can be estimated as the reaction time (residence time). In addition, when the reaction substrate is circulated in the catalyst structure to carry out the reaction, the circulation flow rate can be determined based on the space velocity expressed by Equation (3) below.

The space velocity is not particularly limited and is, for example, from 0.005 to 5000 per minute, preferably from 0.05 to 500 per minute, and even more preferably from 0.5 to 50 per minute. If the space velocity is too low, the CO ₂ will be used up before it passes through the catalyst structure, so the reaction efficiency may be low and side reactions may increase. On the other hand, a higher volume velocity requires a larger pump size, which can lead to poor energy efficiency. The carbonate ester can be efficiently produced by circulating the reaction substrate containing the raw material in the carbonate ester maker at a space velocity in the above range, for example, 0.005 to 5000 (per minute).

[0078]

Thus, the carbonate ester can be efficiently produced. In addition, since the catalyst structure 1 according to the above embodiment is used in this embodiment, the solid catalyst 40 is prevented from being separated from the catalyst structure and crushed. Therefore, the catalytic structure 1 can be reused even under the severe environmental conditions required for the industrial process. In addition, the catalyst component can be adjusted to further improve the activity of the solid catalyst 40, which can be maintained for a long time.

[0079]

<4. Carbonate Ester Machine>

The carbonate ester production apparatus based on the preferred embodiment will be described below. The device for producing carbonate ester contains the above-described catalytic structure for producing carbonate ester. As a specific example, the carbonate ester producing apparatus 60 includes a housing 62 shown in Figures 4 and 5. ester 1. The carbonate ester maker 60 preferably comprises a plurality of carbonate ester 1 catalyst structures, said carbonate ester 1 catalyst structures being arranged, for example, in series.

[0080]

The carbonate ester maker 60 is provided by a feed 64 that can feed the carbonate ester feedstock, namely monohydric alcohol and carbon dioxide, to the carbonate ester catalyst structures 1. As shown by Arrow A in Figure 4, when the above-described feedstock is fed into the carbonate ester producing apparatus 60 through the introduction path 64, the carbonate ester producing reaction proceeds inside the carbonate ester producing catalyst structure 1. Then, as shown by Arrow B in Figure 4, the carbonate ester produced in the reaction the carbonate ester maker is discharged from the carbonate ester maker 60 along with the unreacted feedstock and the rest through the discharge path 70.

[0081]

In order to control the temperature of the carbonate ester production reaction, a heat transfer fluid (not shown) is supplied to the carbonate ester production apparatus 60. The heat transfer fluid can increase the temperature of the catalyst structure to produce the carbonate ester 1 and control the reaction temperature. Therefore, the carbonate ester maker 60 is provided with a heating medium supply pipe 66 for supplying a heat transfer fluid. The heat transfer fluid is supplied to the carbonate ester maker 60 through the inlet 66A of the heating medium supply pipe 66 as shown by Arrow C in Figure 4, and is discharged from the carbonate ester maker 60 through outlet 66B as shown by Arrow D in the Figure. 4. Then, the temperature of the heat transfer fluid is adjusted to a predetermined temperature and re-supplied to the carbonate ester maker 60 through the inlet 66A of the heating fluid supply pipe 66.

[0082]

The shape of the carbonate ester maker 60 is not limited to the described shape. For example, in order to increase the flow rate of the fluid containing the feedstock supplied through the injection route, the carbonate ester producing apparatus can be designed in a form adapted to increase in size. Thus, if the size of the carbonate ester making apparatus needs to be increased, a plurality of integrated structures 2 can be arranged vertically in a row, each including a plurality of parallel carbonate ester producing catalytic structures 1, as shown in the example of Figure 6. In the apparatus for to obtain a carbonate ester 60A having such a structure, apparently only the integrated structure 2 containing the catalytic structure 1 degraded after long-term operation can be easily replaced, and thus the operating cost of the apparatus required for catalysis can be minimized. Each of the structures 2 containing a plurality of parallel integrated catalyst structures for producing carbonate ester 1, preferably provided with a sealing structure to allow fluid flow through the catalyst structures 1. In addition, when the plurality of structures 2 containing a plurality of parallel integrated catalyst structures for producing carbonate ester 1 are arranged vertically in a row, preferably provided with a space between them to ensure a stable flow of fluid in the carbonate ester maker 60A. In order to closely space the catalyst structures 1 in the cross section of the carbonate ester apparatus to minimize the size of the apparatus, a cuboid catalyst structure 1B such as that shown in Figure 7(B) can be used. By using such a cuboid catalytic structure 1B, a plurality of catalyst structures 1B can be closely spaced in the cross section of the carbonate ester making machine, thus minimizing loss of reservoir capacity. The shape of the catalytic structure 1B, however, is not particularly limited, and the catalytic structure 1B may have a shape other than a cuboid. In addition, the catalytic structure 1B preferably has a porous, foamy, honeycomb-like or grid-like structure.

The integrated structure 2 preferably includes a fixed plate 62A as part of the casing 62 to support the plurality of catalytic structures 1B. The fixed plate 62A is provided with frames 62B matching the outer shape of the catalytic structures 1B. The catalytic structure 1B is releasably fixed in the frame 62B as shown by the arrow in Figure 6. In addition, instead of the catalytic structure 1B, a cuboid-shaped honeycomb structure 1C containing no catalyst can be added to the integrated structure 2. Structure 1C having a cuboid honeycomb structure but not carrying a catalyst can be used so that the total amount of catalyst included in the carbonate ester maker 60A is not excessive. Several (e.g., 1 or 2) catalyst-free designs 1C may be provided in an integrated design 2 containing several dozen (e.g., about 30 to 40 as shown in Figure 6) catalyst designs 1B to control catalyst distribution at an appropriate level and suppression of the formation of by-products.

The carbonate ester production apparatus 60A having a structure in which the catalyst structures 1 are arranged not only in series but also in parallel, in other words, a plurality of integrated structures 2 arranged in series, each containing a plurality of catalyst structures 1 in parallel, can be advantageously used in a reaction system in which the flow rate of the fluid containing the raw material is, for example, 500 m ³ /h or more, and preferably 550 m ³ /h or more. If the fluid is supplied at a lower flow rate, a carbonate ester maker 60 can be used, containing, for example, 10 or less catalyst structures 1 arranged only in a row.

[0083]

<5. Carbonate Ester Equipment>

The carbonate ester production equipment including the carbonate ester production apparatus and the like will be described below based on the preferred embodiment. As can be seen in Figure 7, the carbonate ester production equipment 100 includes a carbonate ester production apparatus 60, a feed supply system for supplying raw materials to the carbonate ester production apparatus 60, and a collection system for collecting the produced carbonate ester.

[0084]

When the internal pressure in the CO ₂ tank 72, which is part of the supply system, is increased using the CO ₂ pressure pump 73, carbon dioxide from the CO ₂ tank 72 enters the buffer tank 74. At the same time, liquid monohydric alcohol and 2- cyanopyridine as a raw material stored in the raw material tank 76 is supplied from the raw material tank 76 to the buffer tank 74 by means of the raw material pump 78. Accordingly, carbon dioxide, monohydric alcohol and other raw materials supplied through separate lines to the buffer tank 74 are mixed in buffer tank 74. The mixture is fed into the carbonate ester maker 60 through the first filter 80.

[0085]

In the carbonate ester production apparatus 60, the ester catalyst structure 1 accelerates the carbonate ester production reaction, and a carbonate ester corresponding to the kind of monohydric alcohol in the raw material is formed. The obtained carbonate esters are supplied to the collecting system through the second filter 82. In the collecting system, the liquid containing the carbonate ester and the liquid containing the unreacted raw materials, namely, monohydric alcohol, 2-cyanopyridine, etc., are separated, and then a pump to circulate the reaction solution 84 sends the liquid containing the carbonate ester to the liquid extraction pump 86, while the liquid containing the monohydric alcohol is sent back to the buffer tank 74. Liquids other than the carbonate ester are removed by the liquid extraction pump 86, obtaining a high purity carbonate ester.

EXAMPLES

[0086]

Below, the present invention will be described in more detail by way of Examples and Comparative Examples, although the present invention is not limited to these Examples and Comparative Examples.

[0087]

(Example 1)

1. Obtaining a catalytic structure

Cerium oxide (HSA-20SP available from Solvay Special Chem Japan, Ltd., average particle size: about 10 µm, impurity content: 0.02% or less) was calcined for 3 hours in air at 873 K to obtain a powdered solid catalyst . More specifically, 20 g of cerium oxide was placed in a crucible in a muffle furnace (FO310 available from Yamato Scientific Co., Ltd.) and the temperature was raised at a rate of 10° C./min to 873 K before calcination. The obtained solid catalyst binding silica (Sumiceram P-750 (basically a mixture of siloxane and water based binder) available from ASAHI Chemical Co., Ltd.) and water was weighed to obtain a mass ratio of 2.05:1:1, obtaining 50 g of the catalytic bed mixture used to fill a 50 cm ³ beaker.

In addition, to form an intermediate layer between the catalyst layer and the catalyst-coated base material, a 50 cm ³ beaker was filled with 50 g of a silica binder stock solution. As the catalyst-coated material, a cylindrical metal honeycomb with a diameter of 19 mm, a length of 20 mm, and a density of 100 cells/in ² (steel type: YUS205M1, plate thickness: 50 µm, fin shape (corrugated foil) shape: sine wave, available from Nippon Steel and Sumikin Materials Co., Ltd.). these metal honeycombs were placed in the above-described beaker filled with a mother liquor of a silica binder. After confirming that the combs were completely immersed in the solution, the combs were removed and the excess liquid was purged with a stream of nitrogen. The resulting coated honeycomb was dried at 80°C and cured at 150°C to obtain a honeycomb coated with an intermediate layer to which about 30 g/m ^{2 of} silicon dioxide was attached, i.e. binding component. The thickness of the film of the intermediate layer in this case was estimated at about 20 μm.

These honeycombs were then placed in a beaker containing the above mixture of cerium oxide and binder. After confirming that the combs were completely immersed in the solution, the combs were removed and the excess liquid was purged with a stream of nitrogen. The resulting coated honeycombs were dried at 80°C and cured at 150°C, thereby depositing silica, i.e. binder, and cerium oxide, on the surface of the intermediate layer, and obtaining a catalytic structure according to the present example, which was finally coated with about 15 g/m ² cerium oxide. The film thickness of the catalytic layer in this case was estimated at about 14 µm. Furthermore, if only the binder were similarly dried and cured as described above, its BET specific surface area would be 59 m ² /g.

[0088]

2. Obtaining a carbonate ester

Five catalytic structures obtained (each containing 0.3 attached cerium oxide) were used and fixed in the center of a 1 inch stainless steel tube serving as a fixed bed reactor (see Figures 4 and 5). 323 g of 1-propanol and 93 g of 2-cyanopyridine were weighed and mixed in a molar ratio of 6:1, obtaining a mixture, which was fed into the above fixed-bed reactor at a flow rate of 150 ml/min using a circulation pump, while CO ₂ was introduced into the purge pipe. Then the pressure was increased to an absolute value of 1.0 MPa. In addition, using a heater raised the temperature to 132°C. The reaction was allowed to proceed for 6 hours from the moment the desired temperature was reached. After 6 hours of reaction at 132°C, the reactor was cooled to room temperature, then the pressure was reduced to normal pressure and the internal standard substance was added, i.e. 1-hexanol. The resulting product was collected and analyzed by GC (gas chromatography).

[0089]

The synthesis reaction rate was determined by calculating the yield of DPrC, namely the yield of dipropyl carbonate as the product obtained (hereinafter referred to as "DPrC"), as well as the mole ratio of by-products and DPrC, based on the concentration of each of the components according to the following equation below (where By-products refer to water produced together with DPrC and products other than 2-picolinamide (hereinafter referred to as "2-PA"), which is a hydrate of 2-cyanopyridine (hereinafter referred to as "2-CP"). By-products were propyl carbamate, propyl picolinate, propyl pyridine-2-carboximidate and the like.

[0090]

If alcohol (mol)/nitrile group (mol) ≥2:

Yield of DPrC (mole %)=((molar mass of DPrC)/(molar mass of nitrile group fed)) x 100

[0091]

If alcohol (mol) / nitrile group (mol)<2:

Yield DPrC (mole %)=(2 x (molar mass of DPrC)/(molar mass of 1-propanol fed)) x 100

[0092]

By-products/DPrC (mole %)=(sum of molar masses of by-product components)/(molar masses of DPrC) x 100

[0093]

As a result, under the above conditions, the yield of DPrC was 55 mol. % and the ratio of side products/DPrC was reduced to 1.0 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was repeatedly calcined and used many times under the above reaction conditions, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0094]

More specifically, the presence of deterioration in reaction efficiency due to reuse of the catalyst with recalcination and the presence of catalyst dropout were evaluated by the following criteria, none of which were observed in Example 1. Recalcination of the catalyst was carried out by washing the used catalyst structure with the same kind of alcohol that was used for the synthesis of dialkyl carbonate, and then calcining the resulting structure at 300°C for 3 hours on a heat-resistant plate in a muffle furnace, after adjusting the oxygen concentration in the air to a level equal to or less than the explosive limit of alcohol by mixing nitrogen with air. Alternatively, the catalyst can be re-calcined without removing the catalyst structure from the reactor, but leaving the catalyst structure fixed in the reactor, by carrying out the calcination in the same manner as described above, except that a muffle furnace is not used.

[0095]

(Presence of deterioration in reaction efficiency)

Deterioration in reaction efficiency was considered "present" if the yield of the carbonate ester was reduced by 5 mol. % or more compared with the first application, and the deterioration of the reaction efficiency was considered "absent" if the yield of the carbonate ester decreased by less than 5 mol. %.

(Presence of falling away)

Catalyst dropout was considered "present" if the post-reaction weight of the catalytic structure decreased by 0.2 g or more compared to the pre-reaction weight (about 8.80 g), and catalyst dropout was considered "absent" if the post-reaction weight of the catalytic structure decreased by less than 0.2 g.

The presence of a deterioration in the reaction efficiency and the presence of a catalyst falling off during the reaction and calcination were similarly evaluated in the Examples and Comparative Examples given in the present specification.

[0096]

(Examples 2-4)

The catalytic structures of Examples 2 to 4 were prepared in the same manner as in Example 1, except that the cerium oxide was applied by re-dipping the metal honeycomb into the coating liquid containing the cerium oxide powder several times to attach the cerium oxide in an amount of about 30 g/m ² , 70 g/m ² and 150 g/m ² , respectively. The catalytic layers of the resulting structures had film thicknesses estimated at about 20 µm, about 50 µm, and about 100 µm, respectively.

[0097]

When the reactions were evaluated using each of the catalytic constructs, the catalytic construct bearing 30 g/m ² of catalyst according to Example 2 showed a DPrC yield of 57 mol. % and the ratio of by-products/DPrC, reduced to 1.2 mol. %. The catalytic structure from Example 3, carrying 70 g/m ² of catalyst, showed a yield of DPrC of 52 mol. % and the ratio of by-products/DPrC, reduced to 1.4 mol. %. The catalytic structure of Example 4, carrying 150 g/m ² of catalyst, showed a yield of DPrC of 42 mol. % and the ratio of by-products/DPrC, reduced to 2.7 mol. %. In addition, on all structures, the cerium oxide powder did not fall off the base and had high adhesion even after the reaction. In addition, after each structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that cerium oxide did not fall off from the base material.

[0098]

(Example 5)

The same cerium oxide powder as in Example 1 was weighed, a silica binder (Sumiceram, P-700-D (preferably a mixture of silica powder with an average particle size of about 5 μm, a siloxane-based binder and water), available from ASAHI Chemical Co., Ltd.) and water to give a weight ratio of 2:0.95:1.5 to give 50 g of the catalyst bed mixture, which was used to fill a 50 cm ³ beaker. The remainder of the procedure was as in Example 2, resulting in a catalyst structure bearing 30 g/m ² of catalyst according to Example 5. The film thickness of the catalyst layer was estimated to be about 20 µm. The reaction was evaluated using this construct and a yield of DPrC of 54 mol was obtained. % and the ratio of by-products/DPrC, reduced to 0.9 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction.

In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material. More specifically, after the activity evaluation described above, the catalyst structure of Example 5 was subjected to a regeneration treatment by calcination for 3 hours in air at 573 K, and again subjected to activity evaluation. As a result, the yield of DPrC was 54 mol. % and the ratio of by-products/DPrC was 0.9 mol. %, that is, the same as in the initial evaluation of Example 5. In addition, the cerium oxide powder did not fall off the base and had high adhesion even after the reaction.

[0099]

(Examples 6 and 7)

Catalyst structures according to Examples 6 and 7 were prepared similarly to Example 1, except that cylindrical metal honeycombs with a diameter of 19 mm, a length of 20 mm and a density of 300 and 300 cells per square inch were used as metal honeycombs of the base material (steel type: YUS205M1, plate thickness: 50 µm, fin shape (corrugated foil: sine wave, available from Nippon Steel and Sumikin Materials Co., Ltd.), respectively, and the amount of attached cerium oxide was 30 g/m ^2. The film thickness of the catalytic layer in both cases When each of the constructs was evaluated in the reaction, the 200 cells per square inch catalytic design of Example 6 showed a DPrC yield of 58 mole % and a byproduct/DPrC ratio reduced to 1.1 mole %. The 300 cells per square inch catalytic design of Example 7 showed a DPrC yield of 59 mole % and a by-products/DPrC ratio reduced to 1.0 mole. %. In addition, in both designs, the cerium oxide powder did not fall off the base material and had high adhesion even after the reaction. In addition, when each of the structures was re-calcined and used many times in the same manner as Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0100]

(Example 8)

The same cerium oxide powder as in Example 1 was weighed, a silica binder (Sumiceram, P-700-D (preferably a mixture of silica powder with an average particle size of about 5 μm, a siloxane-based binder and water), available from ASAHI Chemical Co., Ltd.) and water to give a weight ratio of 2:0.95:1.5 to give 50 g of the catalyst bed mixture, which was used to fill a 50 cm ³ beaker. The remainder of the procedure was the same as Example 2, except that no silica pre-binder was applied to create an intermediate layer between the catalyst layer and the catalyst-coated base material, resulting in a catalyst structure with 30 g/m ² attached catalyst according to Example 8. the catalytic layer was estimated to be about 20 µm. The reaction was evaluated using this construct and a yield of DPrC of 54 mol was obtained. % and the ratio of by-products/DPrC, reduced to 0.9 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. When this structure was re-calcined and used in the same manner as Example 1, the reaction characteristics hardly changed, but it was confirmed that a part of the cerium oxide powder fell off from the base material, although the degree of said falling off was acceptable.

[0101]

(Example 9)

A catalyst component other than the examples described above was used as follows.

More specifically, sodium hydroxide was introduced into a solution obtained by dissolving cerium nitrate and zirconium nitrate, in which cerium was 20 at.mass. %, getting a precipitate. The precipitate was filtered off, washed with water, and calcined for 3 hours in air at 1273 K. Then, sieves were used to differentiate particle sizes, obtaining a cerium-zirconium oxide powder with an average particle size of about 10 μm and an impurity content of 0.1% or less. The remainder of the procedure was as in Example 2, resulting in a catalyst structure bearing 30 g/m ² of catalyst. The film thickness of the catalytic layer was estimated to be about 20 µm. The reaction was evaluated using this construct and a yield of 48 mol DPrC was obtained. % and the ratio of by-products/DPrC, reduced to 0.8 mol. %. The cerium-zirconium oxide powder did not fall off from the base material and had high adhesion even after the reaction. When this structure was re-calcined and used in the same manner as Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium-zirconium oxide powder did not fall off from the base material.

[0102]

(Examples 10-14)

Catalyst constructs were prepared analogously to Example 1. Catalyst constructs were prepared and evaluated analogously to Example 1, except that methanol, ethanol and n-butanol (primary alcohols), isopropanol as secondary alcohol and tert- butyl alcohol (tertiary alcohol), respectively. As a result, the yields of dimethyl carbonate, diethyl carbonate, dibutyl carbonate, diisopropyl carbonate and di-tert-butyl carbonate were 56 mol. %, 55 mol. %, 52 mol. %, 48 mol. % and 42 mol. %, respectively, while the ratio of side products/carbonate ester were reduced to 0.8 mol. %, 0.9 mol. %, 1.0 mol. %, 1.4 mol. % and 1.8 mol. %, respectively. In all cases, the cerium oxide powder did not fall off the base material and had high adhesion even after the reaction. In addition, when these structures were re-calcined and used in the same manner as Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0103]

(Examples 15-17)

The catalyst structure of Example 5 was evaluated in a reaction similar to that described in Example 3, except for the reaction pressure of 2.0 MPa, 4.0 MPa and 8.0 MPa, respectively. As a result, the yields of DPrC were 55 mol. %, 55 mol. % and 54 mol. %, respectively, and the ratio of by-products/DPrC were reduced to 0.7 mol. %, 0.6 mol. % and 0.5 mol. %, respectively. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when these structures were re-calcined and used in the same manner as Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0104]

(Example 18)

Cerium oxide (HS, average particle size: about 5 μm, impurity content: 0.02% or less, available from Daiichi Kigenso Kagaku Kogyo Co., Ltd.) was calcined for 3 hours in air at 873 K to obtain a powdery solid catalyst . The obtained powder was used to obtain a catalytic structure similar to Example 1, except that the amount of attached catalyst was 200 g/m ² . The thickness of the film of the intermediate layer in this case was estimated at about 140 μm. The reaction was evaluated using the indicated construct and a yield of DPrC under the indicated conditions was 40 mol. %. The ratio of by-products/DPrC was reduced to 2.9 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0105]

(Example 19)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that SUS304 was used as the honeycomb base material. The result was a yield of DPrC under these conditions, equal to 51 mol. %. The ratio of by-products/DPrC was reduced to 1.2 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0106]

(Example 20)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that ceramic (400 cells per square inch, cylindrical, trade name: Honeyceram, available from NGK Insulators, Ltd.) was used as the honeycomb base material. As a result, the yield of DPrC under these conditions was 50 mol. %. The ratio of by-products/DPrC was reduced to 1.2 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

(Example 21)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that a silica sol (available from JGC Catalyst and Chemicals Ltd.) was used as the inorganic binder. as a result, the yield of DPrC under these conditions was 54 mol. %. In this case, the ratio of by-products/DPrC was reduced to 1.1 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0107]

(Example 22)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that alumina sol (available from Nissan Chemical Corporation) was used as the inorganic binder. As a result, the yield of DPrC under these conditions was 51 mol. %. The ratio of by-products/DPrC was reduced to 1.2 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0108]

(Example 23)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that benzonitrile was used as the hydration agent. As a result, the yield of DPrC under these conditions was 40 mol. %. At the same time, the ratio of by-products/DPrC was reduced to 2.8 mol. %. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was re-calcined and used in the same manner as in Example 1, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material.

[0109]

(Comparative example 1)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that the pressure of nitrogen gas was increased during the purge after the application of cerium oxide powder, whereby the final amount of attached cerium oxide was 8 g/m ² . The thickness of the film of the intermediate layer in this case was estimated at about 6 μm. %. At the same time, the ratio of by-products/DPrC increased to 3.6 mol. %. The cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction.

[0110]

(Comparative example 2)

The catalytic structure was prepared and evaluated in a reaction similar to Example 1, except that the amount of attached cerium oxide was 250 g/m ² . The thickness of the film of the intermediate layer in this case was estimated at about 180 μm. The reaction was evaluated using this construct and a yield of DPrC of only 22 mol was obtained. %. At the same time, the ratio of by-products/DPrC increased to 4.5 mol. %. The cerium oxide was partially detached from the base material, and the adhesion after the reaction was insufficient.

[0111]

The above results are summarized in Tables 1 to 4.

In each table: "metal honeycomb 1" refers to 100 cells per square inch cylindrical metal honeycomb (steel type: YUS205M1, plate thickness: 50um, fin shape (corrugated foil) shape: sine wave, available from Nippon Steel and Sumikin Materials Co. ., Ltd.); "metal honeycomb 2" refers to 200 cells per square inch cylindrical metal honeycomb (steel type: YUS205M1, plate thickness: 50 µm, fin shape (corrugated foil) shape: sine wave, available from Nippon Steel and Sumikin Materials Co., Ltd. ); "metal honeycomb 3" refers to 300 cells per square inch cylindrical metal honeycomb (steel type: YUS205M1, plate thickness: 50um, fin shape (corrugated foil) shape: sine wave, available from Nippon Steel and Sumikin Materials Co., Ltd. ); "metal honeycomb 4" refers to 100 cells per square inch cylindrical metal honeycomb (steel type: SUS304, plate thickness: 50 µm, fin shape (corrugated foil) shape: sine wave, available from Nippon Steel and Sumikin Materials Co., Ltd. ); and "ceramic honeycomb" refers to 400 cells per square inch cylindrical ceramic honeycomb (trade name: Honeyceram, available from NGK Insulators, Ltd.).

In addition, in each table, "silica 1" refers to silica obtained from Sumiceram, P-750 (available from ASAHI Chemical Co., Ltd.); "silica 2" refers to silica obtained from Sumiceram, P-700-D (available from ASAHI Chemical Co., Ltd.); “Silica 3Ni” refers to silica obtained from a silica sol (available from JGC Catalyst and Chemicals Ltd.); and "alumina" refers to alumina obtained from an alumina sol (available from Nissan Chemical Corporation).

[0112]

[Table 1]

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 catalytic design Base material View Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 2 Metal honeycombs 3 Form Fin Fin Fin Fin Fin Fin Fin Number of cells (cells/inch ² ) 100 100 100 100 100 200 300 catalytic layer solid catalyst View CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ Average particle size (mm) 10 10 10 10 10 10 10 Quantity based (g/m ² ) 15 thirty 70 150 thirty thirty thirty Type of inorganic binder Silica 1 Silica 1 Silica 1 Silica 1 Silica 2 Silica 1 Silica 1 The presence of an intermediate layer Present Present Present Present Present Present Present Reaction conditions Monohydric alcohol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol Hydration agent 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine Reaction pressure (MPa) 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Ratings Yield of carbonate ester (mole %) 55 57 52 42 54 58 59 By-Products/Carbonate Ester Ratio (mole %) 1.0 1.2 1.4 2.7 0.9 1.1 1.0 Yield of carbonate ester after catalyst re-calcination (mole %) 55 57 51 42 53 58 59 Deterioration of reaction efficiency due to repeated use (repeated use after calcination of the catalyst) Absent Absent Absent Absent Absent Absent Absent Mass difference of catalytic structure before and after reaction/calcination (g) 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Presence of falling away Absent Absent Absent Absent Absent Absent Absent Catalyst Thickness (µm) 15 20 50 100 20 20 20

[0113]

[Table 2]

Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 catalytic design Base material View Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Form Fin Fin Fin Fin Fin Fin Fin Number of cells (cells/inch ² ) 100 100 100 100 100 100 100 catalytic layer solid catalyst View CeO _{2 CeO2} , _ZrO2 CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ Average particle size (mm) 10 10 10 10 10 10 10 Quantity based (g/m ² ) thirty thirty 15 15 15 15 15 Type of inorganic binder Silica 2 Silica 1 Silica 1 Silica 1 Silica 1 Silica 1 Silica 1 The presence of an intermediate layer Absent Present Present Present Present Present Present Reaction conditions monohydric alcohol 1-propanol 1-propanol methanol ethanol n-butanol isopropanol tert-butyl alcohol Hydration agent 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine Reaction pressure (MPa) 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Ratings Yield of carbonate ester (mole %) 54 48 56 55 52 48 42 By-Products/Carbonate Ester Ratio (mol %) 0.9 0.8 0.8 0.9 1.0 1.4 1.8 Yield of carbonate ester after catalyst re-calcination (mole %) 54 49 56 55 51 48 41 Deterioration of reaction efficiency due to repeated use (repeated use after calcination of the catalyst) Absent Absent Absent Absent Absent Absent Absent Mass difference of the catalytic structure before and after the reaction/calcination (g) 0.2 0.0 0.0 0.0 0.0 0.0 0.0 Presence of falling away Weakly present Absent Absent Absent Absent Absent Absent Catalyst Thickness (µm) 20 20 15 15 15 15 15

[0114]

[Table 3]

Example 15 Example 16 Example 17 Example 18 Example 19 Example 20 Example 21 catalytic design Base material View Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 4 ceramic honeycomb Metal honeycombs 1 Form Fin Fin Fin Fin Fin Fin Number of cells (cells/inch ² ) 100 100 100 100 100 400 100 catalytic layer solid catalyst View CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ CeO ₂ Average particle size (mm) 10 10 10 5 10 10 10 Quantity based (g/m ² ) thirty thirty thirty 200 15 15 15 Type of inorganic binder Silica 2 Silica 2 Silica 2 Silica 1 Silica 1 Silica 1 Silica 3 The presence of an intermediate layer Present Present Present Present Present Present Present Reaction conditions Monohydric alcohol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol 1-propanol Hydration agent 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine 2-cyanopyridine Reaction pressure (MPa) 2.0 4.0 8.0 1.0 1.0 1.0 1.0 Ratings Yield of carbonate ester (mole %) 55 55 54 40 51 50 54 By-Products/Carbonate Ester Ratio (mole %) 0.7 0.6 0.5 2.9 1.2 1.2 1.1 Yield of carbonate ester after catalyst re-calcination (mole %) 54 55 54 39 51 50 53 Deterioration of reaction efficiency due to repeated use (repeated use after calcination of the catalyst) Absent Absent Absent Absent Absent Absent Absent Mass difference of catalytic structure before and after reaction/calcination (g) 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Presence of falling away Absent Absent Absent Absent Absent Absent Absent Catalyst Thickness (µm) 20 20 20 150 15 15 15

[0115]

[Table 4]

Example 22 Example 23 Comparative Example 1 Comparative Example 2 catalytic design Base material View Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Metal honeycombs 1 Form Fin Fin Fin Fin Number of cells (cells/inch ² ) 100 100 100 100 catalytic layer solid catalyst View CeO ₂ CeO ₂ CeO ₂ CeO ₂ Average particle size (mm) 10 10 10 10 Quantity based (g/m ² ) 15 15 8 250 Type of inorganic binder Aluminium oxide Silica 1 Silica 1 Silica 1 The presence of an intermediate layer Present Present Present Present Reaction conditions Monohydric alcohol 1-propanol 1-propanol 1-propanol 1-propanol Hydration agent 2-cyanopyridine benzonitrile 2-cyanopyridine 2-cyanopyridine Reaction pressure (MPa) 1.0 1.0 1.0 1.0 Ratings Yield of carbonate ester (mole %) 51 40 thirty 22 By-Products/Carbonate Ester Ratio (mol %) 1.2 2.8 3.6 4.5 Yield of carbonate ester after catalyst re-calcination (mole %) 50 40 31 15 Deterioration of reaction efficiency due to repeated use (repeated use after calcination of the catalyst) Absent Absent Absent Present Mass difference of the catalytic structure before and after the reaction/calcination (g) 0.0 0.0 0.0 0.7 Presence of falling away Absent Absent Absent Present Catalyst Thickness (µm) 15 15 10 200

[0116]

Thus, in Examples 1-23, the carbonate esters were obtained in good yield and the formation of by-products was reduced. In addition, the catalyst structures of Examples 1 to 23 were able to withstand deterioration in reaction efficiency (catalytic activity) and catalyst separation even after repeated use.

[0117]

On the other hand, in Comparative Examples 1 and 2, the yields of carbonate esters were low because the amount of solid-based catalyst was either too large or too small, and the amount of by-products formed was large. In addition, in Comparative Example 2, where there was a larger amount of solid catalyst on the basis, deterioration in efficiency was observed due to falling off and separation of the solid catalyst.

[0118]

In addition, when the solid catalyst was subjected to the reaction in the same manner as in Example 1 without the use of a base material, the powdered solid catalyst was further crushed and caused clogging of the filters, making further work difficult.

[0119]

(Example 24)

A catalytic structure bearing 30 g/m ² attached cerium oxide according to Example 2 was used for evaluation in a continuous flow reaction. The prepared buffer tank was filled with 445 g of a solution of the same composition that was used for the reaction. The reaction solution was fed from this tank into the reactor at a rate of 111 g/h, and the same amount of solution was withdrawn from the reactor. The residence time of the reaction solution in the reactor was 240 minutes, which is 2/3 of the time according to Examples 1 to 7.

[0120]

As a result, the outputs of DPrC after 6, 12, 18 and 22 hours of reaction were in total about 29 mol. %. The by-product/DPrC ratios were 0.8 mol at these times. %, 1.0 mol. %, 1.0 mol. % and 1.0 mol. %, respectively, confirming saturated and stable conditions. In addition, the cerium oxide powder did not fall off from the base material and had high adhesion even after the reaction. In addition, when this structure was repeated several times, the reaction characteristics hardly changed, and it was confirmed that the cerium oxide powder did not fall off from the base material. Therefore, the catalytic design according to the present invention has also been shown to be useful in a continuous reactor adapted to a high feed rate.

[0121]

(Example 25)

A catalyst component other than the above examples was prepared as follows.

First, lanthanum oxide (LaO ₃ ⋅⋅H ₂ O) as a catalyst precursor was dissolved in 2 g of ultrapure water in a 20 ml sample vial.

At the same time, 2.5 g of CeO ₂ , already calcined at 600° C. for 3 hours, was stirred into a 50 ml glass beaker. The solution containing the precursor was uniformly added to the CeO ₂ in the beaker, and the result was stirred with a glass rod. The beaker was placed on a heated stirrer, the temperature of which was previously set to about 80°C, and the solution in the beaker was stirred with a glass rod. Stirring was continued with a glass rod, keeping the metal components in a homogeneous state, until the water evaporated.

In addition, 2 g of ultrapure water was put into a vial containing the precursor solution to rinse the vial, and the resulting solution was poured into a beaker containing CeO ₂ . Then stirring with a glass rod until the water evaporated and subsequent rinsing was repeated one more time in the same way. The resulting product was dried on a heated stirrer for about 2 hours to completely evaporate the water from the beaker.

The catalyst precursor components were transferred from the beaker to a crucible and calcined in a muffle furnace. The calcination program was set to raise the temperature at a rate of 2°C/min and calcinate at 400°C for 4 hours.

[0122]

The obtained catalyst from Example 25 and the comparative example prepared in the same manner as described in Example 25 but without lanthanum oxide were used to prepare a carbonate ester under the conditions described below.

[0123]

(Reaction conditions for producing carbonate ester)

-Molar feed ratio: (PrOH)/(2-CP)/(Catalyst (CeO ₂ +LaO ₃ or CeO ₂ ))

=300/50/1

- Catalyst: sample attached to foil (approx. 150 g/m ² )

- Amount of reaction solution: 325g

- The amount of the supplied / discharged solution: 162.5 g / h

- Stay time: 2 hours

-Reaction pressure: 0.9Mpa

- Reaction temperature: 132°C

The results obtained are shown in Figure 3. As can be seen from the graph in Figure 3, the catalyst of Example 25 proved to maintain high catalytic activity for a long time by controlling the catalyst components without performing a regenerating treatment such as the calcination described in Example 1. More specifically, as can be seen in the graph shown in Figure 3, where a reference catalyst was used as a comparison, the yield of the carbonate ester was high immediately after the start of the reaction, but it was found that the activity decreased. On the other hand, when the catalyst of Example 25 was used, the excellent catalytic activity was maintained without significant change even after 50 hours of reaction.

[0124]

Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to these embodiments. One of ordinary skill in the art to which the present invention pertains will, of course, understand various changes and modifications within the scope of the technical ideas defined by the claims, and such changes and modifications should be considered as properly falling within the technical scope of the present invention.

DESCRIPTION OF POSITIONING DESIGNATIONS

[0125]

1, 1A Catalyst design for carbonate ester production

10 Base material

20 Catalyst layer

30 Interlayer

40 Solid catalyst

50 Inorganic binder

60 Carbonate ester plant

100 Carbonate ester equipment

Claims (32)

1. A method for producing a carbonate ester, which includes the step of enabling the interaction of monohydric alcohol and carbon dioxide with each other in the presence of a catalytic structure and a hydration agent to form a carbonate ester, where: the catalytic structure comprises a base material and a catalytic layer formed on at least a portion of the surface of the base material and containing a solid catalyst and an inorganic binder; the solid catalyst contains cerium oxide; the amount of solid catalyst based is from 15 to 200 g/m ² ; And the inorganic binder contains silicon dioxide and/or alumina. 2. A method for producing a carbonate ester according to claim 1, characterized in that said inorganic binder contains silicon dioxide. 3. The method of obtaining a carbonate ester according to any one of paragraphs. 1 or 2, characterized in that said catalytic structure further comprises an intermediate layer consisting of an inorganic binder formed between the catalytic layer and the base material. 4. The method of obtaining a carbonate ester according to any one of paragraphs. 1-3, characterized in that the amount of solid catalyst based in the catalytic layer is from 15 to 150 g/m ² . 5. The method of obtaining a carbonate ester according to any one of paragraphs. 1-3, characterized in that the amount of solid catalyst based on is from 15 to 70 g/m ² . 6. The method of obtaining a carbonate ester according to any one of paragraphs. 1-5, characterized in that said base material contains through holes that serve as passageways for monohydric alcohol and carbon dioxide, and the catalytic layer is formed on the surface of said through holes. 7. The method of obtaining a carbonate complex ester according to any one of paragraphs. 1-6, characterized in that said solid catalyst additionally contains an oxide of a rare earth element. 8. A method for producing a carbonate ester according to claim 7, characterized in that said solid catalyst contains lanthanum oxide. 9. The method of obtaining a carbonate ester according to any one of paragraphs. 1-8, characterized in that the average thickness of the catalytic layer is 12-180 microns. 10. The method of obtaining a carbonate ester according to any one of paragraphs. 1-9, characterized in that said base material is a metal honeycomb. 11. The method of obtaining a carbonate ester according to any one of paragraphs. 1-10, characterized in that said hydration agent contains a nitrile compound. 12. The method of obtaining a carbonate ester according to any one of paragraphs. 1-11, characterized in that said hydration agent contains 2-cyanopyridine. 13. A catalytic structure for producing a carbonate ester, containing: base material; And a catalytic layer formed on at least a part of the surface of the base material and containing a solid catalyst and an inorganic binder, Where: said solid catalyst contains cerium oxide; the amount of solid catalyst based is from 15 to 200 g/m ² ; And said inorganic binder contains silicon dioxide and/or alumina. 14. A catalytic structure for producing a carbonate ester according to claim 13, characterized in that the amount of solid catalyst on the basis is from 15 to 150 g/m ² . 15. A device for producing a carbonate ester, comprising: a catalytic structure for producing a carbonate ester according to any one of paragraphs. 13 or 14; And an introduction route for supplying at least a monohydric alcohol and carbon dioxide to said catalytic structure. 16. The carbonate ester maker according to claim 15, further comprising an excretion route through which the carbonate ester derived from a monohydric alcohol and carbon dioxide exits. 17. A device for producing a carbonate ester according to any one of paragraphs. 15 or 16, characterized in that a plurality of catalytic structures are arranged in one line. 18. A device for producing a carbonate ester according to any one of paragraphs. 15 or 16 comprising an integrated structure including a plurality of parallel catalytic structures. 19. A method for producing a carbonate ester, comprising the step of circulating a reaction substrate containing a monohydric alcohol and carbon dioxide through a device for producing a carbonate ester according to any one of paragraphs. 15-18 with a space velocity (per minute) from 0.005 to 5000, where the space velocity (per minute) is expressed by the following equation: space velocity (per minute) = circulation flow rate (m ³ /min) / catalyst structure volume (m ³ ).

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