KR20220034486A - Homogeneous catalyst for preparing alkylene carbonate, method for preparing the catalyst, method and apparatus for preparing alkylene carbonate using the catalyst - Google Patents

Abstract

The present invention relates to a phosphate group (-PO_4^3-)- or phosphate (-PO_4)-containing catalyst for preparing an alkylene carbonate, particularly to a catalyst for preparing an alkylene carbonate, containing an imine group (-C=N-), halide-, amine group (-NH_2), hydroxyl group (-OH), and phosphate group (-PO_4^3-)- or phosphate (-PO_4), a method for preparing the same, and a method and apparatus for preparing an alkylene carbonate through the reaction of an alkylene oxide with carbon dioxide by using the catalyst. The catalyst according to the present invention is a homogeneous catalyst, accelerates the reaction of an alkylene oxide with carbon dioxide, and has high durability to provide an alkylene carbonate stably with a high yield even under a high-temperature reaction condition.

Description

Homogeneous catalyst for preparing alkylene carbonate, method for preparing same, and method and apparatus for preparing alkylene carbonate using the catalyst

The present specification relates to a homogeneous catalyst for preparing an alkylene carbonate containing a phosphoric acid group or a phosphate, a method for preparing the same, and a method and apparatus for preparing an alkylene carbonate using the catalyst.

Alkylene carbonates such as ethylene carbonate and propylene carbonate are widely used as solvents and diluents in industrial processes, and are also used as cosmetic raw materials and electrolytes for secondary batteries. In addition, since it can be used as an intermediate in the preparation of alkylene glycol from alkylene oxide, interest in alkylene carbonate is increasing recently.

A conventional method of reacting ethylene glycol and phosgene (COCl ₂ ) was used to prepare the alkylene carbonate. This reaction proceeds without a catalyst at room temperature. However, due to the toxicity of phosgene as a raw material and a byproduct problem of hydrogen chloride, which is an environmental pollutant, recently, a process of reacting alkylene oxide with carbon dioxide is mainly used.

However, the reaction process for producing alkylene carbonate by reacting alkylene oxide with carbon dioxide, unlike the phosgene process that proceeds without a catalyst at room temperature, requires a reaction under high temperature and high pressure, so that the raw material alkylene oxide is decomposed or There is also the risk of explosion along with the problem that a large amount of by-products are generated by polymerization.

In order to solve these problems, research has been conducted to develop various catalysts to maintain low-cost and high-efficiency reactions.

For example, Japanese Patent Laid-Open No. 9-67365 describes a method using KI as a catalyst, and Japanese Patent Laid-Open No. 59-13776 discloses tributyl methylphosphonium iodide and tetraalkylphosphonium. A method using a tetraalkyl phosphonium halide is described.

In addition, Japanese Patent Laid-Open No. 9-235252 discloses a method using a polystyrene copolymer having a quaternary phosphonium halide at the terminal group. In this document, it is described that the yield reaches 50-95% when the reaction temperature is reacted at 100-170° C. for 1-5 hours.

However, these catalysts are ionic liquids and are very expensive, and in the process using a commercially available homogeneous catalyst, an inorganic halide catalyst is used. and the moisture content of carbon dioxide and alkylene oxide, which are raw materials, must be controlled to several hundred ppm or less.

In addition, Japanese Patent Laid-Open No. 7-206846 discloses a method using a catalyst in which CsOH, RbOH, and ammonium halide are substituted for an ion exchange resin as a method of using an ion exchange resin.

In addition, U.S. Patent No. 4,233,221 describes a method using ion exchange resins of Dowex and Amberlite series. However, in this method, the yield of alkylene carbonate is only about 30 to 80%.

In addition to the above-mentioned catalysts, U.S. Patent No. 5,283,356 discloses Co, Cr, Fe. A method of using phthalocyanine containing Mn, Ni, Ti, V, Zr, etc. as a catalyst is disclosed, and in Japanese Patent Laid-Open No. 7-206547, rubidium (Rb) instead of hydrogen ions of heteropoly acid Alternatively, a method of using a catalyst replacing cesium (Cs) ions is proposed. However, in both cases, an expensive catalyst is required, and the reaction temperature is mild at 120 to 180° C., but the yield is insufficient at 30 to 90%.

As described above, in order to mass-produce alkylene carbonate in the method according to the prior art, reaction conditions such as high temperature and pressure, long reaction time, and moisture removal from raw materials are difficult, and there is a problem in that selectivity and yield at high temperature are low.

In addition, most of the catalysts of the prior art have poor thermal stability, so they are partially decomposed during a high-temperature reaction or distillation purification process to produce halide ions, and the generated halide ions react with alkylene oxide to produce halide-based by-products, or even to manufacture It may also cause a reverse reaction in which the converted alkylene carbonate is decomposed into carbon dioxide and alkylene oxide.

Therefore, the present inventors promote the reaction between the alkylene oxide and carbon dioxide, in order to produce an alkylene carbonate in a high yield in a short time under mild reaction conditions of low temperature and low pressure, a catalyst for preparing an alkylene carbonate containing an ester group or a carbonyl group, the A manufacturing method and an alkylene carbonate manufacturing method and apparatus using the catalyst have been provided (Korea Patent No. 1804762 and Korean Patent Application Laid-Open No. 2020-21319).

However, it is still required to develop a catalyst having a high yield of alkylene carbonate while being stable even under high temperature reaction conditions and distillation purification process, not under mild reaction conditions of low temperature and low pressure.

In exemplary embodiments of the present invention, in one aspect, the reaction between alkylene oxide and carbon dioxide is promoted, and the alkylene oxide is stable and in high yield even under high temperature reaction conditions and distillation purification process, not under mild reaction conditions of low temperature and low pressure. An object of the present invention is to provide a homogeneous catalyst for preparing an alkylene carbonate capable of producing ene carbonate, a method for preparing the same, and a method and apparatus for preparing an alkylene carbonate using the catalyst.

In exemplary embodiments of the present invention, in another aspect, a homogeneous catalyst for preparing an alkylene carbonate, which has excellent durability at high temperature and can maintain a high yield, a method for preparing the same, and a method for preparing an alkylene carbonate using the catalyst and a method of manufacturing the device.

In exemplary embodiments of the present invention, in another aspect, as a homogeneous catalyst dissolved in reactants and products, it is possible to replace only the catalyst without replacing the existing facilities currently producing alkylene carbonate, alkyl An object of the present invention is to provide a homogeneous catalyst for preparing ene carbonate, a method for preparing the same, and a method for manufacturing an alkylene carbonate using the catalyst and an apparatus.

In exemplary embodiments of the present invention, there is provided a homogeneous catalyst for preparing an alkylene carbonate comprising at least a phosphoric acid group (-PO ₄ ^3- ) or a phosphate (-PO ₄ ). The catalyst is an imine group (-C=N-); halide; amine group (—NH ₂ ); hydroxyl group (-OH); and a phosphoric acid group (-PO ₄ ^3- ) or a phosphate (-PO ₄ );

In exemplary embodiments of the present invention, in another aspect, as a method for preparing a catalyst for preparing the alkylene carbonate, an imine group; halide; amine group; hydroxyl group; It provides a method for preparing a catalyst for preparing an alkylene carbonate comprising; reacting a compound containing a phosphoric acid group or a phosphate with a carboxylic acid precursor (or ester precursor).

In exemplary embodiments of the present invention, there is also provided a method and apparatus for preparing an alkylene carbonate for preparing an alkylene carbonate by reacting an alkylene oxide with carbon dioxide under the catalyst for preparing the alkylene carbonate.

According to exemplary embodiments of the present invention, it promotes the reaction of alkylene oxide and carbon dioxide, and obtains alkylene carbonate in a stable and high yield even under high temperature reaction conditions and distillation purification process, not under mild reaction conditions of low temperature and low pressure it is possible

In addition, the catalyst according to exemplary embodiments of the present invention has excellent durability at high temperatures and can maintain a high yield.

In addition, the catalyst according to exemplary embodiments of the present invention is a homogeneous catalyst that is dissolved in a reactant and a product. It is advantageous from an economic point of view because it can be used only by replacing it. In exemplary embodiments of the present invention, by adding a phosphoric acid group or a phosphate group in addition to an amine group or a hydroxyl group, a hydrophilic group is increased to the catalyst, and a side reaction is suppressed, thereby becoming a high-yield homogeneous catalyst.

Hereinafter, exemplary embodiments of the present invention will be described in detail.

In the present specification, the alkyl group means a straight-chain or branched hydrocarbon, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, and the like, but is not limited thereto.

In the present specification, the aryl group may include both an aromatic group, a heteroaromatic group, and partially reduced derivatives thereof. The aromatic group is a simple or fused cyclic type consisting of 5 to 15 hexagons, and the heteroaromatic group refers to an aromatic group containing at least one oxygen, sulfur or nitrogen.

Examples of representative aryl groups include phenyl, benzyl, naphthyl, pyridinyl, furanyl, thiophenyl, indolyl, quinolinyl, imidazolinyl ), oxazolyl, thiazolyl, tetrahydronaphthyl, etc., but is not limited thereto.

In the present specification, the haloalkyl group refers to an alkyl group in which one or more hydrogens are substituted with halogen, and includes, for example, trifluoromethyl, chloromethyl, and the like, but is not limited thereto.

In exemplary embodiments of the present invention, the homogeneous catalyst for preparing alkylene carbonate includes a phosphate (-PO ₄ ). Phosphate has the effect of preventing side reactions even at high temperatures by increasing the durability of the catalyst itself.

In one embodiment, the homogeneous catalyst for preparing alkylene carbonate is an imine group (-C=N-); halide; amine group (—NH ₂ ); hydroxyl group (-OH); and a phosphoric acid group (-PO ₄ ^3- ) or a phosphate (-PO ₄ ); ingredients together. In this catalyst, the materials are chemically linked to form one compound, thereby promoting the synthesis of alkylene carbonate and maintaining chemically stable durability even at high temperatures.

That is, the catalyst for preparing the alkylene carbonate, unlike the existing catalyst, an imine group (-C = N-) in the catalyst; amine group; hydroxy groups; halide; Phosphoric acid group (-PO ₄ ^3- ) or phosphate (-PO ₄ ) material exists. An amine group and a hydroxyl group promote carbon dioxide absorption, and an imine group (-C=N-) and a halide material are O in alkylene oxide. -Open the ring to cause carbon dioxide addition reaction. Phosphoric acid group (-PO ₄ ^3- ) or phosphate (-PO ₄ ) has the effect of preventing side reactions even at high temperatures by increasing the durability of the catalyst itself, as described above.

In an exemplary embodiment, the catalyst may be a catalyst represented by the following [Formula 1] or [Formula 2].

[Formula 1]

[Formula 2]

In [Formula 1] to [Formula 2], n is each a repeating unit, for example, an integer of 1 to 30

X is a halide material such as I, Br, Cl, and x, y, z is 0<x,y,z<1, and x+y+z=1. A preferable range of the x value is 0.5 to 0.9, and the range of the y and z values is 0.1 to 0.25.

As shown in the above [Formula 1] to [Formula 2], the catalyst for preparing an alkylene carbonate is an imine group (-C=N-), a halide, an amine group (-NH ₂ ), a hydroxyl group (-OH) and a phosphoric acid group (- PO ₄ ^3- ) or a phosphate (-PO ₄ ) component.

In the [Formula 1] to [Formula 2], the halide is F, Cl, Br, or I, and is preferably Br or I or Cl in terms of the large effect of the epoxide O ring opening and carbon dioxide addition reaction.

In exemplary embodiments of the present invention, in another aspect, there is provided a method for preparing a catalyst for preparing an alkylene carbonate, comprising: an imine group; halide; amine group; hydroxyl group; It provides a method for preparing a catalyst for preparing an alkylene carbonate comprising; reacting a catalyst compound containing both a phosphoric acid group or a phosphate salt with a carboxylic acid precursor that is a polycondensation reaction precursor.

In an exemplary embodiment, the method comprises an imine group from an amine precursor, an aldehyde precursor, a halide precursor and a phosphoric acid precursor; halide; amine group; hydroxyl group; generating a catalyst compound comprising a phosphoric acid group or a phosphate salt; The method may further include a step of reacting the catalyst compound with a carboxylic acid precursor (or an ester precursor) to generate a carbonyl group or an ester group in the catalyst compound.

In an exemplary embodiment, the amine precursor is urea, melamine, ethylenediamine, dicyandiamide, cyanamide, guanidine, biguanidine, One or more substances including guanylurea, polycyclic guanidine, and the like may be used.

In an exemplary embodiment, the aldehyde precursor includes formaldehyde, acetaldehyde, propionaldehyde, butylaldehyde, benzaldehyde, glutaraldehyde, glyoxal, malondialdehyde, succindialdehyde ), one or more substances known as aldehydes such as phthalaldehyde may be used.

In one exemplary embodiment, halide and phosphoric acid precursors include, for example, NH ₄ I, NH ₄ Br, NH ₄ Cl, HI, HBr, HCl and (NH ₄ ) ₃ PO ₄ , (NH ₄ ) ₂ HPO ₄ , (NH ₄ ) At least one selected from HPO ₄ , H ₃ PO ₄ and the like may be used.

In an exemplary embodiment, the carboxylic acid precursor is formic acid, acetic acid, propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, polyacrylic acid (PAA), It may be at least one selected from a material containing a carboxyl group, such as graphene oxide and alginic acid.

In exemplary embodiments of the present invention, there is also provided a method for preparing an alkylene carbonate for preparing an alkylene carbonate by reacting an alkylene oxide with carbon dioxide under the catalyst for preparing the alkylene carbonate.

In exemplary embodiments of the present invention, an apparatus for producing an alkylene carbonate for preparing an alkylene carbonate by reacting an alkylene oxide with carbon dioxide is provided, and an apparatus including the catalyst is provided.

In an exemplary embodiment, the alkylene oxide may be represented by the following [Formula 3], and the alkylene carbonate may be a compound represented by the following [Formula 4].

[Formula 3]

[Formula 4]

In the above [Formula 3] and [Formula 4], R1 and R2 may each independently be hydrogen, an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, or an aryl group, and a hexagonal ring together with a carbon atom to which they are bonded can form.

In an exemplary embodiment, the alkylene oxide represented by the [Formula 3] includes, for example, ethylene oxide, propylene oxide, epichlorohydrin, butylene oxide, styrene oxide, cyclohexylene oxide, etc. It is not limited.

In an exemplary embodiment, the amount of the catalyst used is preferably 0.0001-20 parts by weight, more preferably 0.1-5 parts by weight based on 100 weight of the alkylene oxide. If it is less than 0.0001 parts by weight, the reaction rate may be too slow, and if it is more than 20 parts by weight, the reaction rate and selectivity may no longer be improved, so there is no economic benefit.

In an exemplary embodiment, the reaction temperature of the reaction may be 150 ~ 180 ℃ or 150 ~ 180 ℃.

If the reaction temperature is too low, the reaction rate may be slowed, and if the reaction temperature is too high, the alkylene oxide will self-polymerize, and thus the reaction selectivity may be reduced.

In an exemplary embodiment, the reaction pressure of the reaction is 20-100 atmospheres. If the reaction pressure is less than 20 atm, the reaction rate may be slowed, and if it exceeds 100 atm, there is no effect of improving the reaction rate, whereas the equipment cost may be excessive.

In an exemplary embodiment, the yield of the reaction is 90-99%.

In an exemplary embodiment, the reaction time of the reaction is 3 to 5 hours.

In an exemplary embodiment, a reaction solvent is used during the reaction, and the same alkylene carbonate as the product may be used as the reaction solvent. The reason is that since the reactant, alkylene oxide, has a high reactivity and there is a risk of explosion, process safety can be improved by mixing the product, which is a stable alkylene carbonate.

Hereinafter, specific examples according to embodiments of the present invention will be described in more detail. However, the present invention is not limited to the following examples, and various types of embodiments can be embodied within the scope of the appended claims, and only the following examples are provided to ensure that the disclosure of the present invention is complete and at the same time as common in the art. It will be understood that the intention is to facilitate practice of the invention to those skilled in the art.

[Example 1]

Preparation example of novel catalyst 1: phosphoric acid group-containing catalyst

5 g of biguanidine, 2.2 g of ammonium iodide, 5.2 g of 50% glutaraldehyde, and 0.7 g of ammonium phosphate (NH4H2PO4) were placed in a 3-neck flask equipped with a thermometer, reflux condenser and dropping device, and stirred at a reaction temperature of 75°C, pH 3 for 1 hour. do. 5.2 g of 50% glutaraldehyde was additionally added through a dropper, adjusted to pH 4.0 with 20% hydrochloric acid, and reacted for 12 hours.

1.5 g of the catalyst precursor synthesized by the above method, 50 g of distilled water, and 0.5 g of polyacrylic acid were charged into a 100 mL two-neck flask equipped with a reflux device, and the reaction was carried out for 2 hours while stirring at 60°C.

After the reaction, water was removed under reduced pressure using a rotary evaporator, and a novel catalyst powder ([Formula 1]) was synthesized.

[Comparative Example 1]

Comparative Example 1 of a novel catalyst: Catalyst without a phosphoric acid group

5 g of biguanidine, 2.2 g of ammonium iodide, and 5.2 g of 50% glutaraldehyde were added to a 3-neck flask equipped with a thermometer, a reflux condenser and a dropper, and stirred at a reaction temperature of 75° C., pH 3 for 1 hour. 5.2 g of 50% glutaraldehyde was additionally added through a dropper, adjusted to pH 4.0 with 20% hydrochloric acid, and reacted for 12 hours.

1.5 g of the catalyst precursor synthesized by the above method, 50 g of distilled water, and 0.5 g of polyacrylic acid were charged into a 100 mL two-neck flask equipped with a reflux device, and the reaction was carried out for 2 hours while stirring at 60°C.

After the reaction, water was removed under reduced pressure using a rotary evaporator, and a novel catalyst powder without a phosphoric acid group was synthesized.

[Example 2]

Preparation Example 2: Catalyst containing a phosphoric acid group

Urea 3.6g, ammonium iodide 2.2g, glyoxal 3.8g, diethylenetriamine 0.05g, ammonium phosphate (NH4H2PO4) 0.7g were put in a three-neck flask equipped with a thermometer, reflux condenser and dropper, and the reaction temperature was 75℃. , and stirred at pH 3 for 1 hour. 3.8 g of glyoxal was additionally added through a dropping device, and the pH was adjusted to 4.0 with a 20% hydrochloric acid solution, followed by reaction for 12 hours.

1.5 g of the catalyst precursor synthesized by the above method, 50 g of distilled water, and 0.5 g of graphene oxide were charged in a 100 mL two-necked flask equipped with a reflux device, and the reaction was carried out for 2 hours while stirring at 60°C.

After the reaction, water was removed under reduced pressure using a rotary evaporator, and a novel catalyst powder ([Formula 2]) was synthesized.

[Comparative Example 2]

Comparative Example 2 of a novel catalyst: Catalyst without a phosphoric acid group

Put urea 3.6g, ammonium iodide 2.2g, glyoxal 3.8g, and diethylenetriamine 0.05g into a three-neck flask equipped with a thermometer, reflux condenser and dropping device, and stir at a reaction temperature of 75℃, pH 3 for 1 hour. . 3.8 g of glyoxal was additionally added through a dropping device, and the pH was adjusted to 4.0 with a 20% hydrochloric acid solution, followed by reaction for 12 hours.

1.5 g of the catalyst precursor synthesized by the above method, 50 g of distilled water, and 0.5 g of graphene oxide were charged in a 100 mL two-necked flask equipped with a reflux device, and the reaction was carried out for 2 hours while stirring at 60°C.

After the reaction, water was removed under reduced pressure using a rotary evaporator, and a new catalyst powder was synthesized.

[Preparation of alkylene carbonate]

A 100 mL high-pressure reactor was charged with propylene oxide (PO, 10 g, 0.17 mol) as a reactant and the novel catalyst (0.05 g) obtained in Example 1, and then filled with carbon dioxide (CO ₂ ) to raise the temperature to 165 °C.

Carbon dioxide was added again so that the reactor pressure became 20 atm. After reacting for 4 hours, the reactor was cooled to room temperature, and the obtained sample was analyzed by GC/MS. For reference, here, the yield is calculated by the following equation.

Yield (%) = (number of moles of alkylene carbonate produced/number of moles of raw material alkylene oxide) × 100

Similarly, one time alkylene carbonate production experiment was performed using the catalysts of Examples 1 and 2.

The yield was compared with or without phosphoric acid group added to the catalyst as follows (Propylene carbonate synthesis conditions: 165°C, 20 atm, reaction time 4 hours, catalyst concentration 0.5% (wt))

Propylene carbonate yield (%) Presence of phosphate in the catalyst Example 1 95 ○ Comparative Example 1 84 Ⅹ Example 2 96 ○ Comparative Example 2 86 Ⅹ

As such, it was confirmed that the catalyst of the exemplary embodiments of the present invention is a homogeneous catalyst including a phosphoric acid group or a phosphate salt, and thus it is possible to obtain an alkylene carbonate in a high yield even at a high temperature.

Claims (7)

As a catalyst for the production of alkylene carbonate,
Phosphoric acid group (-PO ₄ ^3- ) or phosphate (-PO ₄ ) A catalyst for producing an alkylene carbonate, characterized in that it contains.
The method of claim 1,
The catalyst is an imine group (-C = N-); halide; amine group (—NH ₂ ); hydroxyl group (-OH); and a phosphoric acid group (-PO ₄ ^3- ) or a phosphate (-PO ₄ );
3. The method of claim 2,
The catalyst is a catalyst for preparing an alkylene carbonate, characterized in that the following [Formula 1] or [Formula 2].
[Formula 1]

[Formula 2]

[Formula 1] to [Formula 2], n is a repeating unit, an integer of 1 to 30. X is halide, x+y+z=1, 0<x,y,z<1]
4. The method of claim 3,
In the above, the halide is Br or I or Cl.
[Claim 5] The method for preparing a catalyst for preparing an alkylene carbonate according to any one of claims 1 to 4,
imine group (-C=N-); halide; amine group (—NH ₂ ); hydroxyl group (-OH); And a phosphoric acid group (-PO ₄ ^3- ) or a phosphate (-PO ₄ ); reacting a catalyst compound containing a carboxylic acid precursor with a carboxylic acid precursor;
[Claim 5] A method for preparing an alkylene carbonate comprising reacting an alkylene oxide with carbon dioxide under the catalyst for preparing an alkylene carbonate of any one of claims 1 to 4 to prepare an alkylene carbonate.
An apparatus for producing an alkylene carbonate for producing an alkylene carbonate by reacting an alkylene oxide with carbon dioxide,
[Claim 5] An apparatus for producing an alkylene carbonate comprising the catalyst for producing the alkylene carbonate of any one of claims 1 to 4.