KR100404579B1 - Method for manufacturing n-alkyl-2-pyrrolidone - Google Patents

Abstract

PURPOSE: Provided is a method for manufacturing N-alkyl-2-pyrrolidone by reacting alkylamines under mild reaction condition, thereby producing N-alkyl-2-pyrrolidone(NAP) stablely with high yield for a long time. CONSTITUTION: In a method for manufacturing N-alkyl-2-pyrrolidone by reacting a mixture of gammabutyrolactone(GBL), alkylamine and water in a catalyst reaction system, it is characterized in that the molar ratio of gammabutyrolactone:alkylamine:water is 1:(1-6):(1-18), its reaction temperature and pressure are 200-400 deg.C and 0-20kg/cm¬2G, respectively, it uses beta zeolite(MeNa beta) as a catalyst, and the space speed of reaction products is 0.1-20 hour¬-1.

Description

Method for preparing N-alkyl-2-pyrrolidone

The present invention relates to a method for preparing N-alkyl-2-pyrrolidone (NAP), and more particularly to gamma butyrolactone (GBL) and alkylamines such as monomethylamine, dimethylamine and trimethylamine. Reaction under conditions relates to a method for producing N-alkyl-2-pyrrolidone (NAP) in high yield over a long period of time.

NAP, in particular N-methyl-2-pyrrolidone (hereinafter referred to as NMP), is a low viscosity, colorless, non-toxic organic solvent having excellent heat resistance. In addition, because it is a chemically stable and highly polar solvent, it is very useful for various chemical reactions requiring an inert medium. NMP itself is used as a starting material for various organic synthesis, and is widely used as a solvent for polymerization process and membrane processing of high functional resins such as polyphenylene sulfide, polyimide, polyether ketone, aramid, and the like. do.

Until now, various techniques have been proposed as a method of manufacturing such NAP. A method for preparing NMP by alkylation of 2-pyrrolidinone with methyl iodide was first reported in 1907 (J. Tafel, O. Wassmuth, Ber., 40 (1907) 2839, Kirk-Othmer , "Encyclopedia of Chemical Technology", John Wiley & Sons, 19 (1982) pp. 514-520). In recent years, NMP is generally manufactured on an industrial scale by the Reppe process, and NMP is obtained in a yield of 85 to 90% by reaction at a temperature of 250 ° C. or more for several hours (Chem. Ing. Technik (22)). 17, 1950, pp. 361).

The production of NMP can be classified into two types: a high pressure batch or a tubular liquid phase reaction without a catalyst and a gas phase catalytic reaction.

First, as a high pressure liquid phase reaction method without using a catalyst, 2 mol of GBL and 4 mol of monomethylamine are added to a batch reactor and reacted at 280 ° C for 4 hours to produce NMP in a yield of 90 to 93%. J. Amer by McElvain and John F. Vozza. Chem. Soc., 71 (1949) 896, BASF, which produces 2-pyrrolidone by reacting GBL and ammonia in a tubular reactor at reaction conditions of 270 ° C. and 120 atm. A method is disclosed in British Patent 1312463, which may be prepared by using monomethylamine instead of ammonia based on a similar process (Kirk-Othmer, "Encyclopedia of Chemical Technology", John Wiley & Sons, 19 ( 1982) pp. 514-520).

In addition, GBL, water, monomethylamine, dimethylamine, trimethylamine, and the like were reacted for 3 hours in a high pressure batch reactor at a reaction condition of 240 to 265 ° C. and 50 atm, yielding N-alkyl-2-pyrroli in a yield of 94.3%. A method of making money is disclosed in Japanese Patent Laid-Open No. 1-190667. In addition, as reported in Japanese Patent Publication No. 47-21420, 1.48 mol of 1.5 mol GBL, 3 mol of water, and 3 mol of liquid monomethylamine were placed in an autoclave and reacted at 250 ° C. for 2 hours. NMP was obtained.

However, the high pressure liquid phase reaction without the catalyst usually requires a high pressure of more than 50 atm and a reaction temperature of more than 250 ℃, and most of the reaction results are evaluated to be insufficient level of NMP.

Secondly, as a flow catalyzed method, GBL and various alkylamines were continuously reacted on a copper ion-exchanged Y zeolite catalyst at 280 ° C. and atmospheric pressure, yielding N-methyl-2-pi in a yield of up to 98% for 3 hours. The results of the manufacture of Ralidone were reviewed by K. Hatada and Y. Ono Bull. Chem. Soc. As reported in Japan, 50 (10) (1977) 2517, GBL and methylamine were continuously reacted at 300 ° C. for 4 hours on a chromium ion exchange ZSM-5 zeolite catalyst, yielding N-methyl-2- in a yield of 98.2%. Methods for preparing pyrrolidone are described in J. Org. Chem., 50 (1994) 3998.

Further, according to Japanese Patent Publication No. 49-20582, a mixed solution of 0.3 mol of GBL and 40% aqueous methylamine solution (0.35 mol based on methylamine) is used for about 140 cc of catalyst such as alumina, silica alumina, activated carbon, silica gel, silica magnesia, etc. The reaction was carried out by flowing with nitrogen gas of 24 cc / min from the top of the reactor at 270 DEG C., which resulted in NMP at a yield of 63 to 93%.

Recently, Akzo Noble has reported in US Pat. No. 5,478,950 the results of continuous reaction at 275 ° C. using a sodium ion exchange X zeolite catalyst to obtain NMP in 96% yield.

However, the results reported as a flow-catalyzed reaction method showed that the yield of NMP was maintained at a level of up to 98% even though the reaction temperature was relatively high at 270 ° C. or higher and the reaction time was short for 3-4 hours. It can be seen that. Considering the reduction of the activity of the catalyst in such a flow-type reaction method, it is considered that there are many problems in the long-term use of the catalyst due to frequent catalyst regeneration and product separation problems. Therefore, there is a demand for the development of a new catalyst or a new reaction system that can obtain a desired product in a mild and long-term stable condition under milder conditions.

Accordingly, an object of the present invention is to improve the problems of the prior art as described above, and to improve the long-term stable high yield of NAP from GBL using a flow-type catalytic reaction system under mild conditions of low temperature and low pressure. To provide.

It is another object of the present invention to provide a novel catalyst system which can be effectively used in the process of the present invention which can produce NAP from GBL in high yields for a long time stable under mild conditions.

The present inventors conducted various studies to solve the problems of the prior art, and as a result, beta zeolites obtained by ion-exchanging a mixture of gamma butyrolactone (GBL), alkylamines and water with at least one metal cation in a flow-type catalysis system The present invention finds that N-alkyl-2-pyrrolidone can be prepared by continuously reacting at a reaction temperature of 200 to 400 ° C. and a reaction pressure of 0 to 20 Kg / cm 2 G in the presence of a side solvent (MeNa β). Was completed.

According to the present invention, there is provided a process for producing N-alkyl-2-pyrrolidone by reacting a mixture of gammabutyrolactone (GBL), alkylamine and water in a flow-catalyzed catalysis system, wherein the N-alkyl of the present invention is provided. In the method for producing 2-pyrrolidone, the molar ratio of gamma butyrolactone to alkylamine to water in the reaction mixture is 1: (1 to 6): (1 to 18), and copper, calcium, magnesium, zinc or sodium In the presence of a beta zeolite catalyst (MeNa β) ion-exchanged with one or more metal cations selected from the group consisting of, the reaction is continuously carried out at a reaction temperature of 200 to 400 ° C. and a reaction pressure of 0 to 20 Kg / cm 2 G N-alkyl-2-pyrrolidone will be prepared.

According to one aspect of the invention, the present invention is one or more metal cations selected from the group consisting of alkali metals, alkaline earth metals or transition elements including copper, calcium, magnesium, sodium or zinc in a sodium beta zeolite (Na β) catalyst In the presence of an ion exchanged catalyst system, GBL is reacted with an excess of an aqueous alkylamine, especially 40% monomethylamine solution, to provide a long-term stable production of N-alkyl-2-pyrrolidone, especially NMP.

According to another aspect of the invention, GBL is reacted with an alkylamine (monomethylamine or dimethylamine or trimethylamine) to produce N-alkyl (methyl or dimethyl or trimethyl) -2-pyrrolidone, a flowable catalyst Mild conditions of a low pressure of preferably 200 to 400 ° C, more preferably 210 to 300 ° C, and low pressure of preferably 0 to 20 Kg / cm 2 G, more preferably 0 to 10 Kg / cm 2 G using a reaction system A new catalyst system is provided for obtaining a desired product in a long time stable high yield.

We investigated the activity of various flow-catalyzed catalytic reaction systems for the production of NAP from GBL and alkylamines. As a result, using a beta zeolite catalyst ion-exchanged with at least one metal cation selected from the group consisting of alkali metals, alkaline earth metals or transition elements containing copper, calcium, magnesium, zinc or sodium, etc. It was confirmed that NAP can be stably produced for a long time with high yield from GBL and alkylamine.

As a result of the comparative analysis of the present inventors, the beta zeolite catalyst system ion-exchanged with at least one metal cation selected from copper, calcium, magnesium, zinc or sodium is milder than the conventional metal ion exchange X, Y, ZSM-5 zeolite catalyst system. It showed high activity under the reaction conditions.

In the present invention, the reaction was carried out continuously in a stainless steel tubular reactor of atmospheric fixed bed flow. In fact, in the case of NMP preparation, GBL and 40% aqueous methylamine solution are pre-mixed with the desired molar ratio (GBL: methylamine: water = 1: 1-6: 1-18) and then with an inert gas using a metering pump. Inject into the reactor. When GBL and 40% aqueous methylamine solution are mixed at room temperature and atmospheric pressure, N-methyl-2-hydroxy butyric acid amide (N-Methyl-2-hydroxy butyric), which is a precursor of NMP, as discussed in JP-A-186864 acid amide) is easily produced. This can be confirmed using a mass spectrometer.

As described in the following Examples and Comparative Examples herein, zeolite and / or silica alumina used as the base material of the catalyst system used commercially available samples, which ion-exchanged or supported metal cations. Examples of the metal compound used for this purpose include nitrates, acetates, carbonates, chlorides, suboxides, oxides, and hydroxides of the respective metals. Among them, nitrates, acetates, carbonates, hydroxides, and the like are preferable. The metal ion-exchanged with zeolite is 0.5-20 weight% in the form of a metal oxide, and 1-10 weight% is preferable.

The catalyst was added to a zeolite or silica alumina in an aqueous solution of 0.05-1 regulation (N) concentration and evaporated with stirring at 70-90 ° C. for 1-5 times. After washing and filtration, 3-10 at 100-120 ° C. It dried for 4 hours and baked for 4 to 10 hours at 400-600 degreeC.

In the present invention, the reaction temperature is set to 200 to 400 ° C, preferably 210 to 300 ° C. At 210 ° C. or lower, especially at 200 ° C. or lower, the activity of the catalyst decreases drastically, while the catalyst activity increases as the reaction temperature increases within the reaction temperature range.

The reaction pressure is basically normal pressure, but in order to facilitate the circulation of the raw material, the pressure of the first part of the catalyst layer was maintained at about 0 to 20 Kg / cm 2 G with an inert gas, in particular argon gas, depending on the type of catalyst. Preferably it is 0.5 to 10 hours ^-1 , More preferably, it is 1 to 4 hours ^-1 .

The molar ratio of the reactants is GBL: amine: water = 1: (1-6): (1-18), but 1: (2-5): (3-10) is preferred.

Hereinafter, the present invention will be described in detail by examples and comparative examples, and the following examples do not limit the scope of the present invention.

Example 1

Example 1 relates to a process for preparing NMP by reacting GBL with methylamine using a 3.3 wt% copper oxide ion exchange beta zeolite (3.3 wt% Cu β) catalyst.

The catalyst was prepared by adding 19 g of 1.5 wt% sodium ion exchange beta zeolite (PQ Corporation, Valfor, CP-806-B, SiO ₂ / Al ₂ O ₃ = 25) to 300 milliliters of an aqueous solution of 0.1 N concentration. Water is evaporated and the remaining slurry is washed with ion exchanged water, filtered and ion exchanged. After ion exchange twice, the solid state sample was heated to 0.5 ° C./min, dried at 110 ° C. for 3 hours, pulverized at room temperature and heated to 0.5 ° C./min, and calcined at 420 ° C. under air atmosphere for 4 hours. It was.

An atmospheric pressure fixed bed flow-type tubular reactor made of stainless steel 316 having an inner diameter of 10 mm and a length of 610 mm was charged by mixing 4 g of a powdered catalyst with 8 g of glass beads, followed by continuous reaction. As the reactants, GBL and 40% aqueous methylamine solution were premixed in a 1: 4 molar ratio (GBL: methylamine: water = 1: 4: 6), and then injected at a rate of 6 ml / h using a metering pump. 100 sccm of (Ar) gas was supplied to facilitate the transfer of raw materials.

The reaction was carried out at 300, 260, 235 and 215 ° C. for 5 hours, respectively, and the reactants and products were analyzed by gas chromatography with a flame ionization detector. The yield of NMP was 100% at 300, 260 and 235 ° C and 98.5% at 215 ° C, respectively, and 1.5% was unreacted N-methyl-2-hydroxybutyric acid amide.

Examples 2-5

1.6 wt% calcium oxide prepared using calcium nitrate salt instead of copper nitrate salt of Example 1 ion exchange beta zeolite (1.6 wt% Ca β, Example 2), 1.3 wt% magnesium oxide prepared using magnesium nitrate salt Ion-exchange beta zeolite (Example 3), H beta zeolite (PQ Corporation, Valfor, CP-811-BL25, SiO ₂ / Al ₂ O ₃ = 25, Example 4), 1.5 used as the base material in Example 1 The same process as in Example 1 was carried out except for using the wt% sodium ion exchange beta-zeolite catalyst (Example 5), respectively.

The results of Examples 1 to 5 are summarized in Table 1.

TABLE 1

Activity Comparison of Metal Ion Exchange Beta Zeolite Catalysts in the Preparation of NMP from GBL

Comparative Examples 1 and 2

16 wt% sodium X-zeolite (Aldrich Chem., Comparative Example 1), 12.7 wt% calcium ion exchange X zeolite (Comparative Example 2) prepared by ion exchange of calcium nitrate salt in the same manner as in Example 1, respectively It is the same as the method in Example 1 except having used for the catalyst.

Comparative Examples 3-7

13 wt% of sodium Y-zeolite (PQ Corporation, Valfor, CBV-100, SiO ₂ / Al ₂ O ₃ = 5.1, Comparative Example 3), prepared by ion exchange of calcium nitrate salt in the same manner as in Example 1 9.8 wt% calcium ion exchange Y zeolite (Comparative Example 4), 6.1 wt% magnesium ion exchange Y zeolite (Comparative Example 5) prepared by ion exchange of magnesium nitrate salt, 10.7 wt% copper prepared by ion exchange of copper nitrate salt The same procedure as in Example 1 was carried out except that ion exchanged Y zeolites (Comparative Example 6) and zinc ion exchanged Y zeolites prepared by ion exchange of zinc nitrate salts (Comparative Example 7) were used as catalysts, respectively.

Comparative Examples 8-10

Silica alumina (Aldrich Chem., Comparative Example 8), 3.4% by weight calcium ion exchange silica alumina (Comparative Example 9) prepared by ion exchange of calcium nitrate salt in the same manner as in Example 1, 1 mol per 20 grams of silica alumina The same procedure as in Example 1 was carried out except that 4.0 wt% sodium-supported silica alumina (Comparative Example 10) prepared by supporting 20 cc of sodium hydrogen carbonate by initial impregnation was used as a catalyst.

Comparative Example 11

The same procedure as in Example 1 was carried out except that 4 g of 9.5 wt% sodium mordenite (Zelinsky Institute of Organic Chemistry, Russia, SiO ₂ / Al ₂ O ₃ = 9.8) was used as a catalyst.

Comparative Example 12

After dissolving 1 g of chromium oxide (Junsei Chem.) In 125 ml of methanol, 10 g of HZSM-5 (PQ Corporation, Valfor, CBV-3020, SiO ₂ / Al ₂ O ₃ = 30) was added and ion exchanged in the same manner as in Example 1. The same procedure as in Example 1 was repeated except that 9.8 wt% chromium ZSM-5 prepared as a catalyst was used.

The results of Comparative Examples 1 to 12 were summarized in Table 2.

Comparative Examples 13-14

In order to examine the effect on the molar ratio of the raw materials, the molar ratio of the raw material GBL and the 40% aqueous methylamine solution was set to 1: 1 (GBL: methylamine: water = 1: 1: 1.5, Comparative Example 13), and 1: 2 ( The same procedure as in Example 2 was carried out except that GBL: methylamine: water = 1: 1: 3, Comparative Example 14) and reacted at 215 ° C.

The result of said comparative example 13 and 14 was put together in Table 3.

TABLE 2

Comparison of activities of various comparative catalysts in the preparation of NMP from GBL (reaction time: 3 hours)

TABLE 3

Effect of reactant molar ratio when using 1.6wt% Ca β catalyst, reaction temperature: 215 ℃

Example 7

In the preparation of NMP from GBL using 1.6 wt% Ca β catalyst, the reaction was carried out at 215 ° C. for about 30 hours in the same manner as in Example 1, and then the catalyst was regenerated at 300 ° C. for 2 hours in an argon gas stream. In addition, the results of reacting for about 40 hours at 215 ° C are shown in Table 4, and it can be seen that the catalyst can be regenerated and used after deactivation to some extent.

TABLE 4

Renewability of catalyst when using 1.6 wt% Ca β catalyst, GBL: methylamine: water = 1: 4: 6

Example 8

1.9 wt% copper oxide ion exchange beta zeolite (1.9 wt% Cu β), 2.6 wt% copper oxide ion in the same manner as in Example 1 to investigate the change in ion exchange concentration of copper oxide in the long-term preparation of NMP from GBL Exchange beta zeolite (2.6 wt% Cu β), 3.4 wt% copper oxide ion exchange beta zeolite (3.4 wt% Cu β) catalyst was prepared and 3.3 wt% copper oxide ion exchange beta zeolite (3.3 wt%) in Example 1 It was reacted with Cu β) catalyst at 215 ° C. for 30 hours each.

Example 9

In the long-term preparation of NMP from GBL, the reaction was performed at 235 ° C. for about 430 hours using the 3.3 wt% Cu β catalyst in Example 1, and it was found that NMP was stably produced with a high yield of 98.5% or more up to about 300 hours. Can be. The reaction results of Example 8 and Example 9 are summarized in Table 5 (GBL: methylamine: water = 1: 4: 6).

TABLE 5

Long-term Activity of Cu β Catalyst with Changes in Ion Exchange Concentrations during the Preparation of NMP from GBL

The present invention is to prepare N-methyl (or dimethyl or trimethyl) -2-pyrrolidone by reacting GBL with methylamine (or dimethylamine or trimethylamine), using a flow-type catalytic reaction system rather than a high-pressure batch liquid phase reaction It is characterized by the development of a new catalytic process using metal ion exchange beta zeolites, such as copper, calcium, magnesium and zinc, to obtain a desired product in a high yield for a long time stably under mild conditions at low temperature and low pressure. Therefore, by using the catalytic process of the present invention, it is possible to continuously prepare N-methyl (or dimethyl or trimethyl) -2-pyrrolidone from GBL in a long-term, stable and high yield under mild conditions compared to the existing process, and decrease the activity of the catalyst. When generated, the catalyst can be regenerated by a simple treatment.

Claims (9)

A method of preparing N-alkyl-2-pyrrolidone by reacting a mixture of gamma butyrolactone (GBL), alkylamine and water in a flow-type catalysis system, wherein the molar ratio of gamma butyrolactone to alkylamine to water is 1: (1-6): (1-18), 200 in the presence of a beta zeolite catalyst (MeNa β) ion-exchanged with at least one metal cation selected from the group consisting of alkali metals, alkaline earth metals or transition elements Of N-alkyl-2-pyrrolidone, characterized in that the reaction proceeds continuously at a reaction temperature of ˜400 ° C., a reaction pressure of 0-20 Kg / cm 2 G and a reactant space velocity of 0.1-20 hours ⁻¹ . Manufacturing method. The beta zeolite according to claim 1, wherein the at least one metal cation selected from the group consisting of alkali metals, alkaline earth metals or transition elements is ion-exchanged with at least one of the metal cations including copper, calcium, magnesium, zinc or sodium. A process for producing N-alkyl-2-pyrrolidone, characterized in that the reaction proceeds in the presence of a catalyst system. The method according to claim 1 or 2, wherein at least one metal cation selected from the group consisting of copper, calcium, magnesium, zinc or sodium and ion-exchanged with zeolite is selected from the group consisting of nitrates, acetates, carbonates, chlorides, suboxides, A process for preparing N-alkyl-2-pyrrolidone, which is provided to zeolite in the form of an oxide or hydroxide. The method of claim 3, wherein at least one metal cation ion-exchanged in the zeolite is present in the form of a metal oxide, the metal oxide is 0.5 to 20% by weight based on the total weight of the metal oxide constituting the zeolite catalyst. The production method of N-alkyl-2-pyrrolidone. The method for producing N-alkyl-2-pyrrolidone according to claim 1, wherein the reaction temperature is 210 to 300 ° C. The method for producing N-alkyl-2-pyrrolidone according to claim 1, wherein the reaction pressure is 0 to 10 Kg / cm 2 G. The method for producing N-alkyl-2-pyrrolidone according to claim 1, wherein the molar ratio of gamma butyrolactone: methylamine: water in the reaction mixture is 1: 2-5: 3-10. . The process for producing N-alkyl-2-pyrrolidone according to claim 1, wherein the reactant is provided at a space velocity of 0.5 to 10 hours ⁻¹ . A method of preparing N-alkyl-2-pyrrolidone by reacting a mixture of gamma butyrolactone (GBL), alkylamine and water in a flow-type catalysis system, wherein the molar ratio of gamma butyrolactone to alkylamine to water is 1: (2-6): (3-18), 210 in the presence of a beta zeolite catalyst (MeNa β) ion-exchanged with at least one metal cation selected from the group consisting of copper, calcium, magnesium, zinc or sodium, 210 N-alkyl-2-pyrrolidone, characterized in that the reaction proceeds continuously at a reaction temperature of ˜300 ° C., a reaction pressure of 0-10 Kg / cm 2 G and a reactant space velocity of 0.5-10 hours ⁻¹ . Manufacturing method.