KR101813747B1 - Method for separating organometallic catalyst - Google Patents

Abstract

The present invention provides a process for preparing a carbonylation reaction mixture comprising the steps of: adding water to a carbonate reaction mixture containing an organometallic catalyst to produce a first reactant in which a heterogeneous metal oxide is formed; Heating and cooling the first reactant to produce a second reactant; Adding an organic solvent to the second reactant to form a precipitate; And recovering the organometallic catalyst by filtering the precipitate.

Description

[0001] METHOD FOR SEPARATING ORGANOMETALLIC CATALYST [0002]

The present invention relates to a process for separating organometallic catalysts of uniform phase present in organic compounds.

Organometallic compounds are used as catalysts for various organic reactions, and they are widely used on an industrial scale. As one example, a metal alkoxide is frequently used as a catalyst for the transesterification reaction. However, in order to separate a catalyst of a homogeneous phase, a distillation method is inevitable. However, there is a disadvantage in that a large amount of steam is used at the time of separating the catalyst by distillation. In addition, the catalyst is discharged together with the high-boiling point organic substances discharged and removed from the system. It is one of the most effective treatment methods of using by-products discharged from the process as fuels. It is difficult to generate combustion residues and reuse them as fuel when the organometallic compounds are contained in the by-products.

On the other hand, a method of using a filter aid such as diatomite, pearlite, or cellulose to filter an organometallic compound having a small particle size is widely used. However, in order to filter the organometallic compound having such a small particle size, a large amount of filtration tank is required, which complicates the process. In addition, a proper filtration aid should be selected, and if the affinity between the organic metal and the filter aid deteriorates, there is a problem that the removal effect of the organic metal compound is deteriorated.

In this regard, Korean Patent Laid-Open Publication No. 1999-0020591 discloses a method of separating and recovering a cobalt-based organometallic compound using a filter aid.

It is an object of the present invention to provide a method for efficiently separating organometallic catalysts present in a homogeneous phase in an organic compound without using a filter aid.

It is another object of the present invention to provide an organometallic catalyst separation method for separating an organometallic catalyst without using a distillation system to reduce energy consumption.

The present invention relates to a method for separating an organometallic catalyst from an organic compound by adding water to a carbonate reaction mixture containing an organometallic catalyst to produce a first reactant having a heterogeneous metal oxide formed therein and heating and cooling the first reactant And recovering the organometallic catalyst by preparing a second reactant, adding an organic solvent to the second reactant to form a precipitate, and filtering the precipitate.

The weight ratio of the carbonate reaction mixture to the water may be from 1: 0.01 to 1: 0.5.

The carbonate reaction mixture may be a product obtained by reacting a dialkyl carbonate, an aromatic hydroxy compound, and an organometallic catalyst.

The heating can be performed at 100 to 270 ° C.

The weight ratio of the carbonate reaction mixture to the organic solvent may be 1: 1 to 1: 100.

The organic solvent may be one or more of methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, heptanol, acetone and tetrahydrofuran, anisole, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate Or more.

The organometallic catalyst may include at least one of metals of Ti, Pb, Ce, Cu, Zn, Fe, Co, Ni, Al, V, Sm, Sn and Zr.

The present invention provides a method for separating an organometallic compound which can remove an organometallic catalyst from an organic compound with high efficiency without using a filtration aid and does not use a distillation method, thereby reducing energy consumption used in a separation process.

1 is a flow chart illustrating a method for separating an organometallic catalyst from an organic compound according to one embodiment of the present invention.

Hereinafter, embodiments of the present application will be described in more detail. However, the techniques disclosed in the present application are not limited to the embodiments described herein but may be embodied in other forms. It should be understood, however, that the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Also, the singular " include " should be understood to include plural representations, unless the context clearly dictates otherwise, and the terms & Parts or combinations thereof, and does not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

Further, in carrying out the method or the manufacturing method, the respective steps of the method may take place differently from the stated order unless clearly specified in the context. That is, each process may occur in the same order as described, may be performed substantially concurrently, or may be performed in the opposite order.

This will be described in detail below.

1, a method for separating an organometallic catalyst from an organic compound according to an embodiment of the present invention comprises adding water to a carbonate reaction mixture containing an organometallic catalyst to produce a first reactant having a heterogeneous metal oxide And heating and cooling the first reactant to produce a second reactant, adding an organic solvent to the second reactant to form a precipitate, and filtering the precipitate to recover the organometallic catalyst. have.

The first reactant preparation step

In this step, water is added to the carbonate reaction mixture.

The carbonate reaction mixture comprising the organometallic catalyst is generally present in homogeneous form with the organometallic catalyst dissolved in the carbonate reaction mixture. Thus, when water is added to the carbonate reaction mixture, the metal component of the organometallic catalyst reacts sensitively with water to form a metal oxide in a heterogeneous form in the carbonate reaction mixture. By forming such a nonuniform phase, filtration becomes possible.

The weight ratio of the carbonate reaction mixture to water may be 1: 0.01 to 1: 0.5, preferably 1: 0.03 to 1: 0.115, more preferably 1: 0.052 to 1: 0.115.

In the above range, the metal of the organometallic catalyst is well reacted with water to form a heterogeneous phase.

The carbonate reaction mixture may be a by-product after the production of the diaryl carbonate. The diaryl carbonate can be produced through at least one of ester exchange reaction using dialkyl carbonate, aromatic hydroxy compound and organometallic catalyst, disproportionation reaction of alkylphenyl carbonate and ester exchange reaction of alkylphenyl carbonate with phenol .

The dialkyl carbonate may be represented by the following formula (1).

[Chemical Formula 1]

In Formula 1, R ₁ is a substituted or unsubstituted C1 to C10 alkyl group, a C3 to C10 cycloalkyl group, or a C6 to C10 aralkyl group.

Specific examples of the dialkyl carbonate include dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, dipentyl carbonate, dihexyl carbonate, diheptyl carbonate, dioctyl carbonate, dinonyl carbonate, didecyl carbonate, dicyclo At least one selected from dicyclohexyl carbonate, dicyclohexyl carbonate, dicycloheptyl carbonate, di (methoxymethyl) carbonate, di (methoxyethyl) carbonate, di (chloroethyl) carbonate, and di (cyanoethyl) carbonate .

The aromatic hydroxy compound refers to phenol and substituted phenol in which one hydroxy group is bonded to the phenyl group. Examples of the substituted phenol include phenol compounds such as cresol, xylenol, trimethylphenol, tetramethylphenol, ethylphenol, propylphenol, butylphenol, diethylphenol, methylethylphenol, methylpropylphenol, Various alkyl phenols such as pentyl phenol, hexyl phenol and cyclohexyl phenol, various alkoxy phenols such as methoxy phenol and ethoxy phenol, and aryl alkyl phenols such as phenyl propyl phenol.

The organic metal catalyst is a homogeneous catalyst containing at least one metal such as Ti, Pb, Ce, Cu, Zn, Fe, Co, Ni, Al, V, Sm, Sn and Zr . Therefore, a catalyst in which these metal components are combined with an organic group can be preferably used. Specifically, _{TiCl 4, Ti (OMe) 4} , (MeO) Ti (OPh) 3, (MeO) 2 Ti (OPh) 2, (MeO) 3 Ti (OPh), Ti (OPh) 4, Pb (OPh) 2 , Fe ₂ Cl ₂ , FeCl ₃ , Fe (OH) ₃ , Fe (OPh) _3, SnCl ₄ , Sn (OPh) ₄ , Bu ₂ SnO and Bu ₂ Sn (OPh) ₂ .

As a byproduct after the diaryl carbonate is produced, an organic metal catalyst, an unreacted raw material (phenol, dialkyl carbonate, etc.), phenyl salicylate, and other substances may be contained in addition to the diaryl carbonate.

The other materials are divided into a material having a high boiling point (at a boiling point of 300 ° C or higher) and a material having a low boiling point (boiling point of less than 300 ° C), and the high boiling point material is the organometallic catalyst compound, phenyl salicylate, xanthone, phenyl phenyl methoxide, 2-phenoxycarboxy-phenylene, etc., and the low-boiling substance may include alkyl phenyl ether, alkylphenyl carbonate, and the like.

The second reactant preparation step

In the step, the first reactant is heated to 100 to 270 ° C. And the heated temperature may be maintained for 0.1 to 4 hours, preferably for 2 to 4 hours. In the above range, the metal component of the organic metal catalyst existing in the organic compound reacts with water to form a metal oxide having a heterogeneous phase.

When the reaction is sufficiently carried out by heating, the reaction is cooled to a temperature of 0 to 90 ° C to prepare a second reactant.

Precipitation step

In this step, an organic solvent is added to the second reactant to precipitate the metal oxide in the heterogeneous phase. Even if a heterogeneous phase metal oxide is obtained in the first reactant, filtration can not be easily performed when the particle size of the metal oxide is small. Therefore, the particle size of the metal oxide is increased to facilitate the filtration by adding an organic solvent .

The organic solvent may be one or more of methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, heptanol, acetone and tetrahydrofuran, anisole, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate Or more can be used. Among them, it is preferable to use methanol.

The weight ratio of the carbonate reaction mixture to the organic solvent may be 1: 1 to 1: 100, preferably 1: 1 to 1:50, and more preferably 1: 1 to 1:20. In the above range, the particle size of the metal oxide by the organic solvent becomes large, and the metal oxide precipitates well.

Filtration and recovery steps

In this step, the precipitated precipitate may be filtered using a filter to remove the precipitate. These precipitates are metal oxides of the organometallic catalyst of high purity and can be recovered through filtration. As the filtration treatment method, general techniques applicable in the technical field can be applied.

The metal oxide of the organometallic catalyst is not left in the filtrate remaining after the filtration. Unreacted raw materials such as diacyl carbonate, phenol and the like remain in the filtrate when the diaryl carbonate is produced. Therefore, these unreacted raw materials can be recovered again and reused.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Example

(65.88 g, 700 mmol), dimethyl carbonate (31.53 g, 350 mmol), and N, N'-bis (2-hydroxybenzyl) -N, N'-dimethyl Ti (OPr) ₂ (0.0102 g, 0.022 mmol), which is a titanium complex of Ti (OPr) ₄ , was added to the reactor, the oxygen in the reactor was replaced with nitrogen, The mixture was maintained at room temperature for one minute, and then cooled with a cooler to prepare a carbonate reaction mixture.

The produced carbonate reaction mixture was subjected to gas chromatography (GC) analysis using an Agilent 7890A (DB-1 column). The results are shown in Table 1. Of the other materials listed in Table 1, the high boiling point material contained the metal component Ti of the organometallic catalyst, and Ti was confirmed to contain 0.84 wt% of the entire carbonate reaction mixture by ICP-OES analysis.

GC analysis results for the carbonate reaction mixture (unit: wt%)


phenol

Diaryl
Carbonate

Phenyl salicylate
Silicate
Other substances
High boiling point material
(Boiling point over 300 ℃) Low-boiling substance
(Less than 300 캜 boiling point)
3.4

24.8
3.4
67.8
0.6

Example 1.

20 g of the carbonate reaction mixture and 1.5 g of water were placed in an internal 200 ml autoclave reactor having an external heater and the reactor was sealed. The temperature was raised to 180 DEG C, the reaction was maintained at the temperature for 2 hours, and the reaction was gradually cooled to about 80 DEG C to take the reaction product in the reactor. 20.15 g of methanol was added to the reaction product to form a precipitate, which was then filtered using a filter having a pore size of 5 탆. The content of Ti in the filtrate was confirmed by ICP-OES analysis.

Example 2.

The procedure was carried out in the same manner as in Example 1 except that the amount of water was changed to 2.3 g.

Example 3 .

The procedure of Example 1 was repeated except that the amount of water was changed to 1.03 g.

Example 4.

The procedure of Example 1 was repeated except that the reaction temperature was changed to 270 캜.

Example 5.

The procedure of Example 1 was repeated except that the reaction temperature was set to 230 캜.

Example 6.

The procedure of Example 1 was repeated except that the reaction temperature was set to 200 캜.

Example 7.

The reaction was carried out in the same manner as in Example 1 except that the reaction time was changed to 4 hours.

Comparative Example 1

Carbonate 20 g of the reaction mixture was filtered at 20 캜 using a filter having a pore size of 5 탆. After filtration, ICP-OES analysis was carried out to confirm the Ti content in the filtrate.

Comparative Example 2

20 g of the carbonate reaction mixture was filtered at 20 DEG C using a filter having a pore size of 5 mu m filled with 10 g of diatomaceous earth as a filtration tank. After filtration, ICP-OES analysis was carried out to confirm the Ti content in the filtrate.

ICP-OES analysis was carried out under the reaction conditions and the filtration conditions in Examples and Comparative Examples, and the measured values of the Ti content in the filtrate and the removal rate of Ti separation are shown in Table 2 below.

Reaction conditions

Filtration conditions
result
Carbonate
The reaction mixture (g)
Water input
(g)
Reaction temperature
(° C)
Reaction time (h) Organic solvent
(MeOH)
input
(g) Filtration auxiliary
(Diatomite) Input
(g) In the filtrate
Ti
content
(%) Ti separation removal rate
(%) Example 1 20 1.5 180 2 20.15 - 0 100 Example 2 20 2.3 180 2 20.15 - 0 100 Example 3 20 1.03 180 2 20.15 - 0 100 Example 4 20 1.5 270 2 20.15 - 0 100 Example 5 20 1.5 230 2 20.15 - 0 100 Example 6 20 1.5 200 2 20.15 - 0 100 Example 7 20 1.5 180 4 20.15 - 0 100 Comparative Example 1 20 - 20 - - - 0.84 0 Comparative Example 2 20 - 20 - - 10 0.84 0

In Examples 1 to 6 in which the organometallic catalyst separation method of the present invention was applied, 100% of the Ti metal in the organometallic catalyst was 100% removed as compared with the Comparative Example, and the organometallic catalyst could be efficiently removed there was.

On the contrary, in Comparative Examples 1 and 2 in which the organometallic catalyst separation method of the present invention was not applied, it was confirmed that the Ti metal of the organometallic catalyst was not separated and contained in the filtrate in the same amount as before filtration.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the embodiments described above are in all respects illustrative and not restrictive.

Claims (7)

Adding water to the carbonate reaction mixture containing the organometallic catalyst to produce a first reactant wherein the metal oxide of the heterogeneity is formed;
Heating and cooling the first reactant to produce a second reactant;
Adding an organic solvent to the second reactant to form a precipitate; And
Filtering the precipitate to recover the organometallic catalyst;
≪ / RTI >
The organic solvent may be one or more of methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, heptanol, acetone and tetrahydrofuran, anisole, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate By weight based on the total weight of the catalyst. The method of separating organometallic catalyst according to claim 1, wherein the weight ratio of the carbonate reaction mixture to the water is 1: 0.01 to 1: 0.5. The method of claim 1, wherein the carbonate reaction mixture is a product obtained by reacting a dialkyl carbonate, an aromatic hydroxy compound, and an organometallic catalyst. The method according to claim 1, wherein the heating is performed at 100 to 270 ° C. The method of claim 1, wherein the weight ratio of the carbonate reaction mixture to the organic solvent is 1: 1 to 1: 100. delete The method of claim 1, wherein the organometallic catalyst comprises at least one of metals of Ti, Pb, Ce, Cu, Zn, Fe, Co, Ni, Al, V, Sm, Sn, Organometallic catalyst separation method.

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