KR100549701B1 - Method for producing cyano group-containing aromatic methylamine - Google Patents

Abstract

In the present invention, in producing a cyano group-containing aromatic methylamine by hydrogenating only one of two nitrile groups of an aromatic dinitrile, in a reaction under low temperature and low pressure using a small amount of the catalyst, the aromatic dinitrile is reacted at a high degree of high yield. It aims to manufacture.

In the present invention, in preparing a cyano group-containing aromatic methylamine from aromatic dinitrile, a Raney catalyst (activated Raney catalyst) activated by contact with hydrogen in a solvent as a catalyst and regenerated by contact with hydrogen in the presence of an alkali in a solvent At least one of Raney catalysts (regenerated Raney catalysts) is used. In a preferred embodiment, the activated Raney catalyst and / or the regenerated Raney catalyst are 0.1-10% by weight, preferably 0.5-5% by weight of the aromatic dinitrile in the activated Raney catalyst, 0.1 to 50% by weight, preferably 0.5 to 20% by weight of the amount is preferably used. Preferably, the activated Raney catalyst is a Raney catalyst containing nickel and / or cobalt obtained by activating in a hydrogen atmosphere in a solvent, and the regenerated Raney catalyst is used when preparing a cyano group-containing aromatic methylamine from aromatic dinitrile. The Raney catalyst is preferably a Raney catalyst obtained by regeneration by contacting hydrogen with hydrogen in the presence of an alkali in a solvent.

Description

Method for preparing cyano group-containing aromatic methylamine

The present invention relates to a method for producing a cyano group-containing aromatic methylamine, and more particularly, to producing a cyano group-containing aromatic methylamine in high yield by efficiently converting aromatic dinitrile using a small amount of catalyst under low temperature and low pressure. It is about a method.

A cyano group-containing aromatic methylamine is a substance useful as a raw material or intermediate of pharmaceuticals, agrochemicals, polymer additives, and other organic compounds, and for example, m- or p-cyanobenzylamine is hydrolyzed to correspond to useful m- or p-. Aminomethyl benzoic acid can be obtained easily.

By the way, the method of adding cyano group containing aromatic methylamine by adding hydrogen only to one of the two nitrile groups of an aromatic dinitrile is the method of Unexamined-Japanese-Patent No. 49-85041, for example. In this method, although a catalyst supporting palladium on a carrier is used as a catalyst, addition of liquid ammonia and an inorganic alkali is essential, and the reaction pressure is high pressure such as 200 kg / cm 2.

In addition, International Publication No. 94/507909 pamphlet used Ranikel and Ranicobalt as a catalyst, and discloses a method for producing aminonitrile by hydrogenating only one nitrile group of aliphatic dinitrile. In this method, there is no description of aromatic dinitrile, and there is a problem that the selectivity to aminonitrile is lowered when the conversion rate of aliphatic dinitrile is increased.

In pamphlet No. 95/502040, a method for producing aminonitrile by partial hydrogenation of a nitrile compound having two or more nitrile groups has been proposed. In this method, ranickel pretreated with an alkanorate such as sodium methoxide is used as a catalyst. In this method, however, dehydration of the solvent is essential, and a pressure of 70 atm is a high pressure. Nevertheless, there is a problem that alkanorate, which is relatively expensive and inconvenient to handle, must be used.

The present inventors tested the hydrogenation of aromatic dinitrile by selecting various reaction temperatures, hydrogen pressures, solvents, reaction times, and catalyst addition amounts in the presence of a conventional Raney catalyst containing nickel and / or cobalt. However, the conversion rate of the aromatic dinitrile as a raw material was low in the range where the amount of this catalyst was added, and cyano group-containing aromatic methylamine could not be obtained in sufficient yield. In addition, the conversion rate improved with the addition of this catalyst, but at the same time, the production of diamino hydrogenated with two nitrile groups of the aromatic dinitrile increased, so that the yield of the desired cyano group-containing aromatic methylamine was hardly increased. .

As described above, even if a conventionally known Raney catalyst containing nickel and / or cobalt was used as it is, it was difficult to produce a high yield of only the cyano group-containing aromatic methylamine by hydrogenating the aromatic dinitrile at a high degree of high rate.

Here, the inventors of the present invention have conducted intensive studies to find a catalyst capable of producing a high yield of cyano group-containing aromatic methylamine by reacting aromatic dinitrile at a high degree of polymerization, and it is effective to use a Raney catalyst that has been subjected to a specific treatment. The present invention has been found to complete the present invention.

The present invention is to solve the problems associated with the prior art as described above, in the hydrogenation of only one of the two nitrile groups of the aromatic dinitrile to produce a cyano group-containing aromatic methylamine, a small amount of catalyst and at low temperature and low pressure The objective is to produce a high yield of cyano group-containing aromatic methylamine from the aromatic dinitrile by hydrogenation of the aromatic dinitrile at a high degree of polymerization by the reaction.

In the present invention, in preparing a cyano group-containing aromatic methylamine from aromatic dinitrile, a Raney catalyst (activated Raney catalyst) activated by contact with hydrogen in a solvent is used as a catalyst.

In the present invention, in preparing a cyano group-containing aromatic methylamine from aromatic dinitrile, the Raney catalyst used is contacted with hydrogen in the presence of an alkali in a solvent to be regenerated, and a cyano group-containing aromatic methylamine is produced from aromatic dinitrile. In this case, the regenerated catalyst (regenerated Raney catalyst) is used.

In the present invention, the activated Raney catalyst and / or the regenerated Raney catalyst are 0.1 to 10% by weight, preferably 0.5 to 5% by weight of the aromatic dinitrile in the activated Raney catalyst, and 0.1 to 50% by weight in the regenerated Raney catalyst. %, Preferably it is preferable to use in the quantity of 0.5-20 weight%.

In the present invention, activation of the Raney catalyst is preferably carried out by contacting the Raney catalyst with hydrogen under a condition of a hydrogen partial pressure of 0.1 to 50 kg / cm 2 at a temperature of room temperature to 200 ° C, and regeneration of the Raney catalyst is supplied to regeneration. It is preferable to carry out by contacting a Raney catalyst with hydrogen on the conditions of 0.1-50 kg / cm <2> of hydrogen partial pressures at the temperature of room temperature-200 degreeC under the alkali coexistence of 0.1-100 weight% of the Raney catalyst.

In the present invention, in producing a cyano group-containing aromatic methylamine from aromatic dinitrile, it is preferable to coexist at least one of iron, iron oxide and iron hydroxide together with the activated Raney catalyst and / or regenerated Raney catalyst.

In this invention, it is preferable to use at least 1 sort (s) among the said iron, iron oxide, and iron hydroxide so that these total amounts may be 0.1-100 weight% of the said Raney catalyst.

In the present invention, the Raney catalyst is preferably a Raney catalyst containing nickel and / or cobalt, more preferably Raney nickel or modified Ra nickel.

In this invention, it is preferable that the said solvent contains alcohol, and it is more preferable that the said solvent is methanol.

In the present invention, the aromatic dinitrile is preferably phthalonitrile, isophthalonitrile or terephthalonitrile.

According to the method for producing a cyano group-containing aromatic methylamine of the present invention, when only one of two nitrile groups (N≡ C-) in the aromatic dinitrile is hydrogenated to produce a cyano group-containing aromatic methylamine, In addition, a small amount of catalyst and a hydrogenated reaction of aromatic dinitrile at a high degree of solidification can be produced by a reaction under low temperature and low pressure to produce a cyano group-containing aromatic methylamine in high yield.

Hereinafter, the manufacturing method of the cyano group containing aromatic methylamine of this invention is demonstrated concretely.

In the present invention, in preparing a cyano group-containing aromatic methylamine from aromatic dinitrile, as a catalyst,

(A) Raney catalyst activated by contact with hydrogen in a solvent (hereinafter also referred to as activation treatment Raney catalyst),

(B) In the preparation of the cyano group-containing aromatic methylamine from aromatic dinitrile, at least one of the Raney catalysts (hereinafter referred to as the regenerating Raney catalysts) regenerated by contacting the used Raney catalyst with hydrogen in a solvent is used. In a preferred embodiment, 0.1 to 10% by weight of the aromatic dinitrile, preferably 0.5 to 5% by weight in the activated Raney catalyst, 0.1 to 50% by weight of the aromatic dinitrile in the regenerated Raney catalyst, preferably Is used in an amount of 0.5 to 20% by weight.

<Activation treatment and regeneration treatment of Raney catalyst>

In the present invention, the "Raney catalyst" activated by contact with hydrogen in a solvent is a porous metal catalyst having a large specific surface area obtained by removing some components included in the alloy from two or more metal alloys,

More specifically, in alloys of metals that are not soluble in alkali or acid (eg nickel or cobalt or both) and metals which are soluble in alkali or acid (eg aluminum, silicon, zinc, magnesium, etc.), alkali or acid A porous metal catalyst obtained by eluting a metal dissolved in an alkali or an acid.

In the present invention, in such a catalyst, a Raney catalyst containing nickel or cobalt or both is preferable, and a nickel-containing Raney catalyst is more preferably used.

In the present invention, modified Raney catalysts modified in the presence of metals or metal oxides other than nickel and cobalt may also be used. Such modified Raney catalysts include, for example, modified Ranikel modified with iron and / or chromium.

In the present invention, such Raney catalyst activation is preferably performed by treating the Raney catalyst under a hydrogen atmosphere in a solvent.

On the other hand, in the present invention, a Raney catalyst which is contacted with hydrogen in a solvent to be regenerated is a Raney catalyst recovered after using the activated Raney catalyst in producing a cyano group-containing methylamine from an aromatic dinitrile.

In the present invention, the regeneration of the Raney catalyst is preferably performed by treating the Raney catalyst under a hydrogen atmosphere in an alkali coexistence in a solvent.

The partial pressure of hydrogen during these activation and regeneration treatments is usually 0.05-100 kg / cm 2, preferably 0.1-50 kg / cm 2, and the internal temperature of the system is usually 0-250 ° C., preferably room temperature [ie, 15-25 ° C.]. It is -200 degreeC. When the partial pressure of hydrogen is less than 0.1 kg / cm 2, in particular less than 0.05 kg / cm 2, and the temperature is below room temperature, especially below 0 ° C., the activation treatment (hydrogen treatment) and the regeneration treatment effect are lowered, and the hydrogen partial pressure is 50 kg / cm 2. Above 100 kg / cm 2 and above 200 ° C., especially above 250 ° C., many diamines in which two nitrile groups are hydrogenated together in aromatic dinitrile are produced or the catalytic activity is deteriorated, resulting in cyano group-containing aromatic methyl. The amine yield may fall.

Furthermore, in the regeneration treatment of Raney catalyst, in order to express the regeneration effect, the regeneration treatment of alkali, preferably inorganic alkali, for example, hydroxide or carbonate of alkali metal, hydroxide or carbonate of alkaline earth metal, or ammonia is performed as described above. It is necessary to add to. Although this alkali addition amount changes also with regeneration conditions, it is normally 0.01-200 weight% of a catalyst amount, Preferably it is 0.1-100 weight%.

The Raney catalyst activation treatment and regeneration treatment may be performed continuously while introducing hydrogen gas or a hydrogen-containing mixed gas into the system under pressurization, or may be carried out in a badge manner in a system in which hydrogen gas is pressurized.

Examples of the solvent include alcohol solvents, ether solvents of aliphatic and alicyclic hydrocarbons, saturated aliphatic and alicyclic hydrocarbon solvents, water and the like. These solvents may be used alone, or may be used in combination of two or more thereof, or may be used as a mixed solvent containing any one or two or more of these solvents and solvents other than these. It is also possible. Among these, as a preferable solvent, the solvent containing an alcohol solvent (for example, the solvent containing methanol) is mentioned, Especially preferably, methanol is used. Although there is no restriction | limiting in particular about the usage-amount of a solvent, The said solvent is used normally 1-1000 weight part, Preferably it is 2-500 weight part with respect to 1 weight part of said Raney catalysts.

The time required for activating or regenerating the Rani catalyst tends to be shorter as the pressure (hydrogen partial pressure) is higher, and longer as the pressure is lower, for example, 10 at a pressure of 50 kg / cm 2. At about 1 minute per minute, about tens of hours are required, but it changes with the kind and conditions of Raney catalyst to be activated or regenerated, and the type and amount of alkali added in the regeneration treatment.

Preparation of Cyano Group-Containing Aromatic Methylamine from Aromatic Dinitrile

In the present invention, the aromatic dinitrile is hydrogen reduced (hydrogenated) in the presence of the activated Raney catalyst to produce a cyano group-containing aromatic methylamine,

First, the aromatic dinitrile supplied to the hydroprocessing is demonstrated.

Aromatic dinitrile

The aromatic dinitrile used in the present invention is a compound in which two of the hydrogen atoms bonded to the aromatic ring are substituted with a nitrile group (N≡ C-). Examples of the aromatic ring include benzene ring, naphthalene ring, anthracene ring, and the like, and these aromatic rings may be bonded to one or two or more chains (e.g., biphenyl), and the remaining part bound to the aromatic ring. The hydrogen atom may be substituted with a halogen atom, an alkyl group (preferably about 1 to 5 carbon atoms), an alkoxy group (preferably about 1 to 5 carbon atoms), or the like. Among such aromatic dinitriles, aromatic dinitrile having one benzene ring or one naphthalene ring is preferable, and more preferably dicyanobenzene and dicyanonaphthalene having only two nitrile groups as substituents. have.

As such aromatic dinitrile specifically, for example,

Dicyanobenzenes such as phthalonitrile, isophthalonitrile and terephthalonitrile;

1,3-dicyanonaphthalene, 1,4-dicyonanaphthalene, 1,5-dicyonanaphthalene, 1,6-dicyanonaphthalene, 2,3-dicyanonaphthalene, 2,6-dicyanonaphthalene, 2, Dicyanonaphthalenes, such as 7-dicyanonaphthalene; Is preferred.

In these, phthalonitrile, isophthalonitrile, and terephthalonitrile of dicyano benzenes is especially preferable. In the present invention, the aromatic dinitrile may be selected from halogen atoms such as fluorine and chlorine in addition to the two nitrile groups; Alkyl groups such as methyl group and ethyl group (preferably about 1 to 5 carbon atoms); Or alkoxy groups (preferably about 1 to 5 carbon atoms) such as methoxy group and ethoxy group; You may further have substituents, such as 2-chloro terephthalonitrile, 2-chloro-4- methyl isophthalonitrile, etc. can be used specifically ,.

Hydrogenation of Aromatic Dinitriles

Preferable conditions of the hydrogen reduction (hydrogenation) reaction of aromatic dinitrile are demonstrated next.

As the Raney catalyst, at least one of the above-mentioned activated Raney catalyst and regenerated Raney catalyst is used, and usually the activated Raney catalyst is 0.1 to 10% by weight of aromatic dinitrile to be hydrogenated (hydrogenated), preferably 0.5 to 5% by weight. In the amount of%, the regeneration catalyst is used in an amount of 0.1 to 50% by weight, preferably 0.5 to 20% by weight.

By using the activated treated Raney catalyst and / or regenerated Raney catalyst in such an amount, cyano group-containing aromatic methylamine in which only one of the two nitrile groups is hydrogenated in the aromatic dinitrile is obtained in high yield. Moreover, when the total weight of these catalysts is less than 0.1 weight%, reaction rate becomes remarkably slow. In addition, when the activation treatment Raney catalyst exceeds 10% by weight, a tendency to generate a lot of diamine hydrogenated with two nitrile groups in the aromatic dinitrile to be hydrogenated occurs, the yield of the cyano group-containing aromatic methylamine is lowered. In addition, even if the total weight of these Raney catalysts exceeds 70% by weight of the aromatic dinitrile to be hydrogenated (hydrogenated), the reaction rate is almost unchanged as compared with 70% by weight, and the yield of the cyano group-containing aromatic methylamine is also remarkable. There is no difference.

In the present invention, in order to improve the yield of the cyano group-containing aromatic methylamine in the hydrogenation of aromatic dinitrile, at least one of iron, iron oxide and iron hydroxide may coexist together with the activated Raney catalyst and / or the regenerated Raney catalyst. Can be.

As such iron, iron oxide or iron hydroxide, preferably, for example, electrolytic iron, reduced iron, ferrous oxide, ferric oxide, iron oxyhydroxide, iron supported on a carrier (for example, alumina-supported iron, silica-supported iron, etc.) For example. The total amount of iron, iron oxide or iron hydroxide to coexist is usually used in an amount of 0.01 to 200% by weight (in terms of iron in iron supported on the carrier), preferably 0.1 to 100% by weight of the Raney catalyst amount.

When iron, iron oxide, or iron hydroxide is used in such a total amount, cyano group-containing aromatic methylamine in which only one of two nitrile groups in the aromatic dinitrile is hydrogenated is obtained in high yield. That is, when the total amount of such iron, iron oxide or iron hydroxide is less than 0.01% by weight of the Raney catalyst, no improvement in yield is observed, and even when such iron, iron oxide, or iron hydroxide coexists more than 200% by weight, when 200% by weight is coexisted. Compared with that, no significant difference is observed in the yield improvement of the cyano group-containing aromatic methylamine.

In addition, in the case of the hydrogenation reaction of such aromatic dinitrile, a solvent can be used normally. As such a solvent, Preferably, alcohol solvent, ether solvent of aliphatic and alicyclic hydrocarbon, saturated aliphatic, and alicyclic hydrocarbon solvent are mentioned, for example.

These solvents can be used independently and can also be used as a mixed solvent containing any of these. Preferred solvents include alcohol solvents or mixed solvents containing alcohol solvents, and methanol is particularly preferably used.

The solvent for hydrogenation of the aromatic dinitrile is not necessarily the same as the solvent used for the activation (hydrogenation) or regeneration of the Raney catalyst, but the activation or regeneration of the catalyst and the hydrogenation of the aromatic dinitrile are carried out in the same solvent. When implemented, there is a big advantage in that the substitution of a solvent becomes unnecessary.

Such a solvent is usually used in an amount of 1 to 30 parts by weight, preferably 1.5 to 10 parts by weight, based on 1 part by weight of the hydride (aromatic dinitrile).

In the present invention, in the hydrogenation of aromatic dinitrile, alkali, preferably inorganic alkali, for example, hydroxides or carbonates of alkali metals, hydroxides or carbonates of alkaline earth metals, or ammonia are used in order to control side reactions to improve selectivity. It may be added during the hydrogenation reaction. Although addition amount changes also with reaction conditions, For example, in the case of hydroxide of an alkali metal, it is 0.01-200 weight% of a catalyst amount normally.

In this invention, the hydrogenation reaction of aromatic dinitrile can be normally performed in 200 degreeC at room temperature (15-25 degreeC), Preferably it is 50-130 degreeC. If it is less than room temperature, a sufficient rate of hydrogenation cannot be obtained, and even if the hydrogenation reaction is carried out at a temperature condition exceeding 200 ° C, the reaction rate, yield, and selectivity no longer show remarkable advantages. The pressure during the hydrogenation reaction is usually in the range of 1 to 100 kg / cm 2 and preferably 2 to 30 kg / cm 2 in terms of hydrogen partial pressure.

The hydrogen gas used in this reaction does not necessarily have to be high purity, and may contain other gases, for example, an inert gas, etc., unless it has a special influence on the hydrogenation reaction.

The hydrogenation reaction is preferably terminated at a stage where hydrogen is absorbed into the reaction system at a theoretical amount, that is, 100 to 120%, preferably 100 to 110% of the theoretical amount.

By hydrogenation of such aromatic dinitrile, only one of the two nitrile groups (N≡ C-) of the aromatic dinitrile becomes "H ₂ NH ₂ C-" (aminomethyl group) with high efficiency, and one nitrile group A cyano group-containing aromatic methylamine having one aminomethyl group is obtained.

In the present invention, the conversion rate of such aromatic dinitrile also varies depending on the type of catalyst and the like, but is not determined in one word, but is usually 90 mol% or more, preferably 95 mol% or more, and the yield of cyano group-containing aromatic methylamine is usually 70% or more, Preferably it is 75% or more.

[Effects of the Invention]

According to the present invention, an activated treated Raney catalyst (preferably a Raney catalyst containing nickel and / or cobalt activated in a hydrogen atmosphere in a solvent), and a regenerated Raney catalyst (preferably in a solvent with an alkali atmosphere in a hydrogen atmosphere) Raney catalyst containing nickel and / or cobalt recycled under the above), in the activated Raney catalyst, preferably 0.1 to 10% by weight of aromatic dinitrile, more preferably 0.5 to 5% by weight, The regenerated Raney catalyst is preferably present in an amount of 0.1 to 50% by weight, more preferably 0.5 to 20% by weight, and particularly preferably at least one of iron, iron oxide and iron hydroxide together with the Raney catalyst. The hydrogen di-reduction of the aromatic dinitrile is carried out by coexisting in an amount of 0.1 to 100% by weight of the catalyst to react the aromatic dinitrile at a high degree of polymerization at low temperature and low pressure. Kigo, while controlling the generation of the two nitrile groups of the aromatic dicyano hydrogenation with dinitrile, and one nitrile-containing aromatic methylamine of deception is hydrogenated cyano group may be prepared in a high yield.

Hereinafter, although the manufacturing method of the cyano group containing aromatic methylamine of this invention is demonstrated further more concretely, this invention is not interpreted at all by the related Example at all.

(Example 1)

<Activation of Catalyst>

180 ml of methanol and 2.0 g of Ranickel Catalyst R-2400 (manufactured by WRGrace) were placed in a 500 ml autoclave, and the hydrogen pressure was adjusted to 5 kg / cm 2 (gauge pressure or less) at room temperature (24 ° C). Stirring and heating of the contents of the clave were started and kept at a temperature of 100 ° C. for 2 hours. The maximum pressure during this heating was 9 kg / cm 2. Next, after cooling the obtained autoclave contents to room temperature, the catalyst was settled and recovered.

Hydrogenation reaction

180 ml of methanol, 1.0 g of activated nickel catalyst, 50 g of terephthalonitrile and 0.2 g of sodium hydroxide were added to a 500 ml autoclave, and the hydrogen pressure was adjusted to 10 kg / cm 2 at room temperature. And hydrogenation of terephthalonitrile. The reaction was terminated when the hydrogen absorption amount became 105% of the theoretical value while maintaining the internal temperature of the system at 100 ° C. and monitoring the hydrogen flow rate with a thermal mass flow meter (manufactured by Kojima Corporation). Next, after cooling the obtained reactant to room temperature, the catalyst was separated by filtration, and when the obtained reaction liquid was analyzed by gas chromatography internal standard method, the conversion rate of terephthalonitrile was 99 mol% or more and p-cyanobenzyl The yield of amine was 80% and the yield of p-xylenediamine was 5%.

(Comparative Example 1)

To a 500 ml autoclave, 180 ml of methanol, 1.0 g of Ranickel catalyst R-2400 (not hydrogenated), WGrace, 50 g of terephthalonitrile and 0.2 g of sodium hydroxide were added. At a pressure of 10 kg / cm 2, stirring and heating of the contents of the autoclave were started to initiate the hydrogenation of terephthalonitrile. When the reaction was carried out while maintaining the internal temperature of the system at 100 ° C. and monitoring the hydrogen flow rate, the reaction did not proceed when the hydrogen absorption amount reached 88% of the theoretical value. Next, when the reaction solution is cooled to room temperature, unreacted terephthalonitrile remains in the reaction solution obtained. When this (unreacted terephthalonitrile) was removed by filtration with a catalyst, and the obtained reaction solution was analyzed by gas chromatography internal standard method, the yield of p-cyanobenzylamine was 47%, and the yield of p-xylenediamine was 2%. The conversion rate of terephthalonitrile was 68 mol% in the analysis of the weight of filtered terephthalonitrile and the reaction liquid by gas chromatography internal standard method.

(Example 2)

<Regeneration of Catalyst>

In a 500 ml autoclave, 180 ml of methanol and hydrogenated reaction of terephthalonitrile under the same conditions as in Example 1 were placed, and after the completion of the reaction, about 1.0 g of a nickel nickel catalyst and 0.2 g of sodium hydroxide separated and recovered were placed, and room temperature ( 24 kg), the hydrogen pressure was 5 kg / cm &lt; 2 &gt;, stirring and heating of the contents of the autoclave were started and held at a temperature of 100 ° C for 2 hours. The maximum pressure during this heating was 7 kg / cm 2. Next, the obtained autoclave contents were cooled to room temperature.

Hydrogenation reaction

50 g of terephthalonitrile was added to a 500 ml autoclave containing the regenerated Ranickel catalyst, the hydrogen pressure was set to 10 kg / cm 2 at room temperature, and the stirring and heating of the contents of the autoclave were started to initiate the hydrogenation of terephthalonitrile. Started. The reaction was terminated when the hydrogen absorption amount became 105% of the theoretical value while maintaining the internal temperature of the system at 100 ° C and monitoring the hydrogen flow rate. Next, after cooling the obtained reaction product to room temperature, the catalyst was isolate | separated and removed by filtration, and when the obtained reaction liquid was analyzed by the gas chromatography internal standard method, the conversion rate of terephthalonitrile is 99 mol% or more, and p-cyano The yield of benzylamine was 77% and the yield of p-xylenediamine was 5%.

(Comparative Example 2)

<Regeneration of Catalyst>

In Example 2, the catalyst was regenerated under the same conditions as in Example 2 except that no sodium hydroxide was added.

Hydrogenation reaction

Hydrogenation of terephthalonitrile under the same conditions as in Example 2 in the presence of the catalyst, cooling to room temperature, filtering the catalyst, and analyzing the obtained reaction solution by gas chromatography internal standard method, the conversion rate of terephthalonitrile Was 99 mol% or more, the yield of p-cyanobenzylamine was 63%, and the yield of p-xylenediamine was 6%.

(Example 3)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

<Regeneration of Catalyst>

The catalyst was regenerated in the same manner as in Example 2.

Hydrogenation

0.5 g of activated Raney catalyst and 50 g of terephthalonitrile were added to a 500 ml autoclave containing the regenerated catalyst. The hydrogen pressure was 10 kg / cm 2 at room temperature, and the stirring and heating of the contents of the autoclave were started. Hydrogenation of ronitrile was initiated. The reaction was terminated when the hydrogen absorption amount reached 105% of the theoretical value while maintaining the internal temperature of the system at 100 ° C and monitoring the hydrogen flow rate. Next, after cooling the obtained reaction product to room temperature, the catalyst was isolate | separated and removed by filtration, and when the obtained reaction liquid was analyzed by the gas chromatography internal standard method, the conversion rate of terephthalonitrile is 99 mol% or more, and p-cyano The yield of benzylamine was 79%, and the yield of p-xylenediamine was 5%.

(Example 4)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

<Hydrogenation>

In Example 1, 0.2 g of reduced iron, 50 g of terephthalonitrile and 0.2 g of sodium hydroxide were added together with 1.0 g of the activated nickel nickel catalyst, and hydrogenation of terephthalonitrile was carried out under the same conditions as in Example 1. After cooling to room temperature, the catalyst and the reduced iron were filtered, and the obtained reaction solution was analyzed by gas chromatography internal standard method. The conversion ratio of terephthalonitrile was 99 mol% or more, and the yield of p-cyanobenzylamine was 85. %, the yield of p-xylenediamine was 4%.

(Example 5)

<Regeneration of Catalyst>

In a 500 ml autoclave, about 1.2 g and 0.2 g of sodium hydroxide were put together in a hydrogenation reaction of 180 ml of methanol and terephthalonitrile in Example 4. The hydrogen pressure was made 5 kg / cm <2> (gauge pressure or less) at (24 degreeC), stirring and heating of the autoclave contents were started, and it hold | maintained at the temperature of 100 degreeC for 2 hours. The maximum pressure during this heating was 6.7 kg / cm 2. Next, the obtained autoclave contents were cooled to room temperature.

Hydrogenation

50 g of terephthalonitrile was added to a 500 ml autoclave in which the regeneration catalyst was accommodated, and a hydrogenation reaction of terephthalonitrile was carried out under the same conditions as in Example 1, and then cooled to room temperature, followed by filtration of the catalyst and reduced iron. When the liquid was analyzed by gas chromatography internal standard method, the conversion rate of terephthalonitrile was 99 mol% or more, the yield of p-cyanobenzylamine was 83%, and the yield of p-xylenediamine was 5%.

(Example 6)

<Activation of Catalyst>

In Example 1, in activating the catalyst, the catalyst was activated under the same conditions as in Example 1 except for changing the used methanol to ethanol.

Hydrogenation

In Example 1, after performing the hydrogenation reaction of terephthalonitrile under the same conditions as in Example 1, cooling to room temperature, filtering the catalyst, and analyzing the obtained reaction liquid by gas chromatography internal standard method, The conversion rate was 99 mol% or more, the yield of p-cyanobenzylamine was 77%, and the yield of p-xylenediamine was 5%.

(Example 7)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

Hydrogenation

In Example 1, except for changing the terephthalonitrile to isophthalonitrile, hydrogenation of isophthalonitrile was carried out under the same conditions as in Example 1, and then cooled to room temperature. After that, the catalyst was filtered and the reaction solution obtained was gas. When analyzed by the chromatography internal standard method, the conversion rate of isophthalonitrile was 99 mol% or more, the yield of m-cyanobenzylamine was 82%, and the yield of m-xylenediamine was 6%.

(Example 8)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

Hydrogenation

In Example 1, except that the amount of the catalyst was changed to 1.5 g, the hydrogenation reaction of terephthalonitrile was carried out under the same conditions as in Example 1, and then cooled to room temperature. After that, the catalyst was filtered and the reaction solution obtained was subjected to gas chromatography. When analyzed by the standard method, the conversion rate of terephthalonitrile was 99 mol% or more, the yield of p-cyanobenzylamine was 79%, and the yield of p-xylenediamine was 5%.

(Reference Example 1)

180 ml of methanol in a 500 ml autoclave, used for hydrogenation of terephthalotryl under the same conditions as in Example 1, and separated and recovered after completion of the reaction, about 1.0 g of unregenerated Ranickel catalyst and 0.2 g of 50 g terephthalonitrile. Sodium hydroxide was added, the hydrogen pressure was set to 10 kg / cm 2 at room temperature, the agitation and heating of the autoclave contents were started, and the hydrogenation reaction of terephthalonitrile was started. The reaction was terminated when the hydrogen absorption amount became 105% of the theoretical value while maintaining the internal temperature of the system at 100 ° C and monitoring the hydrogen flow rate. Next, after cooling the obtained reaction material to room temperature, the catalyst was isolate | separated and removed by filtration, and when the obtained reaction liquid was analyzed by the gas chromatography internal standard method, the conversion rate of terephthalonitrile was 99 mol% or more, but p-cyano The yield of benzylamine was 58% and the yield of p-xylenediamine was 3%.

(Reference Example 2)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

Hydrogenation

In Example 1, the hydrogenation reaction of terephthalonitrile was carried out in the same manner as in Example 1 except that the amount of catalyst was changed to 0.02 g and the sodium hydroxide was changed to 0.005 g, but there was little hydrogen absorption. The conversion rate of terephthalonitrile was less than 1 mol%.

(Reference Example 3)

<Activation of Catalyst>

The catalyst was activated in the same manner as in Example 1.

Hydrogenation

In Example 1, the hydrogenation of terephthalonitrile was carried out under the same conditions as in Example 1 except that the amount of catalyst was changed to 10 g, the reaction pressure (hydrogen pressure) was changed to 5.0 kg / cm 2, and the reaction temperature was changed to 60 ° C. .

Next, after cooling the internal temperature of the system to room temperature, the catalyst was filtered, and when the reaction solution obtained was analyzed by gas chromatography internal standard method, the conversion rate of terephthalonitrile was 99 mol% or more, and p-cyanobenzylamine The yield was 73% and the yield of p-xylenediamine was 17%.

Claims (13)

In preparing cyano group-containing aromatic methylamine from aromatic dinitrile, A method for producing a cyano group-containing aromatic methylamine, characterized by using a Raney catalyst activated by contact with hydrogen in a solvent as a catalyst. In preparing a cyano group-containing aromatic methylamine from an aromatic dinitrile, the Raney catalyst used in preparing a cyano group-containing aromatic methylamine from an aromatic dinitrile is regenerated by contacting with hydrogen in the presence of an alkali in a solvent. A method for producing a cyano group-containing aromatic methylamine, comprising using a Raney catalyst. The Raney catalyst according to claim 1 or 2, wherein the activated Raney catalyst and / or the regenerated Raney catalyst are 0.1 to 10% by weight of the aromatic dinitrile in the activated Raney catalyst, and 0.1 to Using in an amount of 50% by weight. The Raney catalyst according to claim 1 or 2, wherein the activated Raney catalyst and / or the regenerated Raney catalyst are 0.5 to 5% by weight of the aromatic dinitrile in the activated Raney catalyst and 0.5 to 5% in the regenerated Raney catalyst. Using in an amount of 20% by weight. The method according to claim 1, wherein the activated Raney catalyst is a Raney catalyst activated at a temperature of room temperature to 200 ° C under a hydrogen partial pressure of 0.1 to 50 kg / cm 2. The Raney catalyst according to claim 3, wherein the regenerated Raney catalyst is prepared at room temperature under an alkali coexistence of 0.1 to 100% by weight of the Raney catalyst supplied to regeneration of the Raney catalyst used in preparing the cyano group-containing aromatic methylamine from the aromatic dinitrile. Regeneration is carried out under the conditions of a hydrogen partial pressure of 0.1 ~ 50kg cm2 at a temperature of ~ 200 ℃. The method according to claim 1 or 2, wherein at least one of iron, iron oxide and iron hydroxide coexists with the activated Raney catalyst and / or regenerated Raney catalyst. The method of claim 7, wherein at least one of the iron, iron oxide and iron hydroxide is used in an amount of 0.1 to 100% by weight of the Raney catalyst. The method according to claim 1 or 2, wherein the Raney catalyst contains nickel and / or cobalt. The method according to claim 1 or 2, wherein the Raney catalyst is Raney Nickel or modified Raney Nickel. The method of claim 1 or 2, wherein said solvent comprises an alcohol. The method of claim 1 or 2, wherein the solvent is methanol. The method according to claim 1 or 2, wherein the aromatic dinitrile is at least one of phthalonitrile, isophthalonitrile and terephthalonitrile.