KR101178940B1 - Catalyst For Manufacturing Alkylamine And Its Preparing Method - Google Patents

Abstract

The present invention relates to a catalyzed reductive amination reaction of alcohol, and more particularly, to a catalyst capable of effectively preparing an alkylamine at normal pressure by reacting an alcohol with an amine compound in the presence of hydrogen, impregnating a support with cobalt and an iron precursor. The present invention relates to a catalyst supported on cobalt and iron, a method for preparing the same, and a method for preparing an alkylamine using the same.
Cobalt and iron-supported catalyst prepared by the above production method can maintain the catalytic activity stably at normal pressure for a long time instead of the reductive amination reaction at a high pressure, and requires not only isopropyl alcohol but also an amination reaction of alcohols. It is a very economical and efficient catalyst that can be useful in many processes.

Description

Catalyst for preparing alkylamine and preparation method thereof {Catalyst For Manufacturing Alkylamine And Its Preparing Method}

The present invention relates to a catalyst used for the production of alkylamines by reductive amination of alcohols, and more particularly, to catalysts that can effectively prepare alkylamines at normal pressure by reacting alcohols and amine compounds in the presence of hydrogen, preparing them. And a method for producing an alkylamine using the catalyst.

Isopropylamine is a kind of alkylamine and is an important material as an intermediate and raw material in various fields such as chemistry, pharmaceuticals, agriculture, rubber and solvents. In addition, it can be used as a raw material of isopropyl hydroxyamine that serves to control and stop the chain reaction during the polymerization of the polymer.

Reductive amination of alcohol refers to the reaction of primary, secondary or tertiary amine products by reaction with alcohol, ammonia and hydrogen in the presence of transition metal catalysts such as nickel, cobalt and the like which are active in the hydrogenation-dehydrogenation reaction. In general, catalysts useful for the reductive amination of alcohols are known to be useful for the amination of aldehydes and ketones.

In general, as a catalyst for the reductive amination of alcohol, a metal such as nickel or cobalt may be used alone or mixed with other metals (eg, copper, zinc, magnesium, etc.). Typically, reductive amination reactions produce primary amines by the reaction of alcohols with ammonia. Good selectivity for primary amines is usually obtained under high pressure reaction conditions in which secondary alcohols are present in the presence of excess ammonia under suitable catalysts. In addition, before carrying out the reaction, the reducing amination catalyst is reacted by reducing at an appropriate temperature, and it is preferable to add hydrogen gas during the reaction to maintain high catalytic activity and selectivity and catalyst stability.

US Pat. No. 4,255,357 describes a process for producing ethylamines from ethanol using a catalyst prepared by impregnating alumina or diatomaceous earth support with nickel or cobalt. The patent document mentions that catalytically active materials such as cobalt, nickel and the like are supported on a support material selected from a support comprising alumina or diatomaceous earth. Among the active materials used, cobalt is mentioned as more useful for the amination process. .

Fischer, et al. (A. Fischer, et al.) Disclose a method for amination of 1,3-propanediol based on cobalt catalysts (J. Catal. 183, (1999) 373). Amination of 1,3-propanediol using cobalt, cobalt-iron and cobalt-lanthanum catalysts prepared by coprecipitation yielded a desired yield of the desired diamine product at a reaction temperature of 195 ° C. and a high pressure of 135 bar of 35%. Only the following, it was an undesirable catalytic reaction process in consideration of economics with low product yield under high pressure reaction conditions.

US Pat. No. 4,912,260 describes a process for converting isopropyl alcohol to monoisopropylamine under autogenous pressure by liquid phase reaction using a nickel-palladium-ruthenium-alumina catalyst prepared by impregnation. The yield of the desired monoisopropylamine showed a low yield of 12.4 ~ 62.6% depending on the reaction conditions. In addition, there is a difficulty in the continuous reaction process by the liquid phase reaction under autogenous pressure, it was difficult to separate the catalyst.

US Pat. No. 5,932,769 describes a process for converting isopropyl alcohol to monoisopropylamine using a catalyst prepared by impregnating cobalt and palladium on an alumina support. The patent document showed that the cobalt-palladium catalyst had a conversion rate of 90% or more and a monoisopropylamine selectivity of 70% or more under a reaction temperature of 193 ° C. and a pressure of 17 bar. However, since the palladium of expensive precious metals is used as a catalyst and the reaction proceeds under high pressure conditions, the method is economically unfavorable for reductive amination for monoisopropylamine production.

Accordingly, the present inventors have solved the problems of the continuous reaction process and the difficulty of separating the catalyst and the reaction process under high pressure conditions due to the liquid phase reaction, which is a disadvantage of the conventional monoisopropylamine production by reductive amination of isopropyl alcohol. During the study, a catalyst was developed which can effectively prepare monoisopropylamine at atmospheric pressure by reacting isopropyl alcohol with ammonia in the presence of hydrogen, and completed the present invention.

That is, the present invention provides a catalyst and a method for producing monoisopropylamine effectively under normal pressure (pressure of about 1.0) by reacting isopropyl alcohol with ammonia in the presence of hydrogen and maintaining the catalytic activity stably for a long time. It aims to provide. It is another object of the present invention to provide a method for preparing alkylamine using the catalyst.

In order to achieve the above object, the present invention provides a catalyst for the reductive amination reaction of alcohol in which cobalt and iron are supported on a support.

In addition, the present invention provides a method for preparing a catalyst for reducing amination reaction of alcohol, which is stirred or co-cured with an aqueous solution of cobalt precursor or an aqueous solution of iron precursor simultaneously or sequentially.

Finally, in the present invention, the alcohol and the amine compound are mixed under normal pressure (pressure of about 1.0) to form an amination reaction mixture, contacting hydrogen with the catalyst to activate the catalyst and the activation catalyst to the amination It provides a method for producing an alkylamine comprising the step of contacting the reaction mixture to react.

Cobalt and iron-supported catalyst prepared according to the present invention can be efficiently produced alkylamine through high catalytic activity even under normal pressure (pressure of about 1.0), unlike the previous catalyst. Therefore, it is a very economical and efficient catalyst that can be usefully used in various processes requiring alcohol amination reactions.

1 is a graph comparing the results of the reductive amination reaction activity test of Examples 1 to 4.
Figure 2 is a graph showing the results of the reactivity amination reaction activity test according to the space time of the catalyst of Example 1.
3 is a graph showing the results of a reductive amination reaction experiment according to the ratio of hydrogen and isopropyl alcohol of the catalyst of Example 1.
4 is a graph showing the results of a reductive amination reaction experiment according to the ratio of ammonia and isopropyl alcohol of the catalyst of Example 1.
5 is a graph showing the results of a reductive amination reaction experiment of isopropyl alcohol according to the reaction temperature of the catalyst of Example 1.
6 is a graph showing the results of a reductive amination reaction deactivation experiment of the catalyst of Example 1.

The present invention relates to a catalyst for the reductive amination reaction of alcohol in which cobalt and iron are supported on a support.

The support is not particularly limited, but specifically, may be alumina (Al ₂ O ₃ ), silica (SiO ₂ ), alumina-silica, and more specifically γ-Al ₂ O ₃ . The γ-Al ₂ O ₃ is a metal oxide having a specific surface area of about 150 to 300 m ² / g, and is prepared in a gamma phase by calcining an alumina gel at about 600 ° C. Such γ-Al ₂ O ₃ is porous and has high thermal stability. In addition, the purity is high, and has the advantage of having a special form of physical properties by controlling the synthesis conditions.

It is preferable that the support has a specific surface area of 150 to 300 m ² / g because it can be supported at an appropriate ratio of iron and cobalt.

Cobalt and iron in the catalyst is preferably supported to be 5 to 20% by weight relative to the total weight of the catalyst. If less than 5% by weight of the cobalt and iron components are too small may have a problem that the effect of the catalyst as a catalyst in the reductive amination reaction of alcohol, if more than 20% by weight cobalt components evenly dispersed in the support There is a problem.

The preparation of the catalyst may be prepared by stirring the cobalt precursor aqueous solution or the iron precursor aqueous solution simultaneously or sequentially with the support, followed by drying and calcining.

The order of stirring the cobalt precursor aqueous solution and the iron precursor aqueous solution is not particularly limited, and the mixed solution of the cobalt precursor aqueous solution and the iron precursor aqueous solution and the support may be prepared by stirring at a time. However, a sequential method of dry firing after stirring with one precursor aqueous solution followed by dry firing with another precursor aqueous solution is more preferable for forming a microstructure of cobalt-iron.

The cobalt precursor is not particularly limited, but may be cobalt chloride, cobalt acetate, cobalt nitrate, or a mixture thereof. As described above, the cobalt is preferably supported to be 5 to 20% by weight based on the total weight of the catalyst. Therefore, it is preferable to use an appropriate ratio of cobalt precursor mixed with an aqueous solution.

The iron precursor is not particularly limited, but may be ferric chloride, ferric sulfate, iron nitrate or a mixture thereof. As described above, the iron is preferably supported to be 5 to 20% by weight based on the total weight of the catalyst. Therefore, it is preferable to use an appropriate proportion of the iron precursor mixed with the aqueous solution accordingly.

After stirring the cobalt precursor aqueous solution and the iron precursor aqueous solution and the support, it is dried and calcined. The drying may be dried by distillation under reduced pressure at 30 ~ 70 ℃, the firing method may be baked for 1 to 3 hours at 400 ~ 600 ℃ while flowing the air. When firing at a temperature of more than 600 ℃ may cause a problem that the catalyst particles lose the thermal stability due to agglomeration, and when firing at a temperature below 400 ℃ iron ions are the oxide form of Fe ₂ O ₃ There may be a problem indicating that the activity is dropped because it does not exist.

The present invention comprises the steps of mixing the alcohol and the amine compound at normal pressure (pressure of about 1.0) or less to form an amination reaction mixture, contacting hydrogen with the catalyst to activate the catalyst and the activation catalyst to the amination reaction It relates to a method for producing an alkylamine comprising the step of contacting the mixture to react. When the above reaction is carried out in a fixed bed packed reactor, the hydrogen may be added before the amination reaction mixture is added to activate the catalyst and then provided with the amination reaction mixture.

Unlike the conventional high pressure reaction conditions, the method can be prepared at atmospheric pressure instead of reacting in the presence of hydrogen. The hydrogen serves to reduce the catalyst. The specific conditions for the reduction depend on the specific catalyst composition that is activated. Such activation may include alloy formation, suitable phase orientation of the metal, and adjustment of the oxidation level of the metal.

The alcohol may be isopropyl alcohol, the amine compound may be ammonia, methylamine or ethylamine, and the alkylamine may be monoisopropylamine.

The volume ratio of the alcohol and hydrogen is preferably 1: 1 to 20, and the volume ratio of the alcohol and the amine compound is preferably 1: 1 to 15. The space time of the reaction is preferably adjusted to be 30000 ~ 50000 gmin / mmol. In addition, the temperature of the reaction is preferably 180 ~ 240 ℃.

According to the present invention, a catalyst prepared by supporting iron and cobalt on alumina using an impregnation method, which is a general catalyst preparation method, can stably maintain catalytic activity even at normal pressure for a long time, and requires an amination reaction such as alcohols, aldehydes or ketones. It is a very economical and efficient catalyst that can be usefully used in various processes.

Hereinafter, the present invention will be described in more detail with reference to examples, but the following examples are merely to illustrate the present invention, but it should be understood that the present invention is not limited thereto.

Example  1: Preparation of Catalyst

A precursor aqueous solution was prepared by dissolving 15.48 g of iron nitrate hexahydrate (Fe (NO ₃ ) ₃ ˜9H ₂ O) as an iron precursor in 360 ml of distilled water. The precursor solution prepared above was mixed with 16 g of γ-Al ₂ O ₃ , stirred at room temperature and atmospheric pressure (pressure of about 1.0) for 3 hours, and then the mixture was distilled under reduced pressure at 60 ° C. for complete drying. In addition, the dried product was calcined at about 500 ° C. for 2 hours while flowing air to prepare Fe ₂ O ₃ / γ-Al ₂ O ₃ such that the amount of supported iron was 13% by weight.

Cobalt nitrate hexahydrate as the cobalt precursor _{(Co (NO 3) 2?} 6H 2 O) 1.481 g the rear dissolved in distilled water 3.5 ㎖, prepared the aqueous solution in Example _{1 Fe 2 O 3 / γ-} Al 2 O 3 1.7 g After immersion in, the adsorbate was dried at room temperature for about a day. Next, the dried product was calcined at about 500 ° C. for 2 hours while flowing air, thereby preparing Co ₃ O ₄ / Fe ₂ O ₃ / γ-Al ₂ O ₃ having an amount of 15% by weight of cobalt supported.

Example  2: Preparation of Catalyst

A precursor aqueous solution was prepared by dissolving 15.48 g of iron nitrate hexahydrate (Fe (NO ₃ ) ₃ ˜9H ₂ O) as an iron precursor in 360 ml of distilled water. The precursor solution prepared above was mixed with 16 g of γ-Al ₂ O ₃ , stirred at room temperature and atmospheric pressure for 3 hours, and then the mixture was distilled under reduced pressure at 60 ° C. for complete drying, and then the dried product was dried with air. Fe ₂ O ₃ / γ-Al ₂ O ₃ was prepared by baking for 2 hours at about 500 ℃ while flowing the amount of supported iron to 13% by weight.

As a cobalt precursor of cobalt nitrate hexahydrate _{(Co (NO 3) 2?} 6H 2 O) 0.494 g to then carry the rear dissolved in distilled water 3.5 ㎖, the aqueous solution of the _{Fe 2 O 3 / γ-Al} 2 O 3 1.9 g This adsorbate was dried at room temperature for about a day. Next, the dried product was calcined at about 500 ° C. for 2 hours while flowing air to prepare Co ₃ O ₄ / Fe ₂ O ₃ / γ-Al ₂ O ₃ having an amount of 5% by weight of cobalt supported.

Example  3: Preparation of Catalyst

A precursor aqueous solution was prepared by dissolving 15.48 g of iron nitrate hexahydrate (Fe (NO ₃ ) ₃ ˜9H ₂ O) as an iron precursor in 360 ml of distilled water. The precursor solution prepared above was mixed with 16 g of γ-Al ₂ O ₃ , stirred at room temperature and atmospheric pressure for 3 hours, and then the mixture was distilled under reduced pressure at 60 ° C. for complete drying, and then the dried product was dried with air. Fe ₂ O ₃ / γ-Al ₂ O ₃ was prepared by baking for 2 hours at about 500 ℃ while flowing the amount of supported iron to 13% by weight.

Cobalt precursor as cobalt nitrate hexahydrate _{(Co (NO 3) 2?} 6H 2 O) 0.988 g of then after dissolving in distilled water 3.5 ㎖, carrying the aqueous solution in the _{Fe 2 O 3 / γ-Al} 2 O 3 1.8 g This adsorbate was dried at room temperature for about a day. Next, the dried product was calcined at about 500 ° C. for 2 hours while flowing air, thereby preparing Co ₃ O ₄ / Fe ₂ O ₃ / γ-Al ₂ O ₃ having an amount of cobalt supported by 10% by weight.

Example  4: preparation of catalyst

A precursor aqueous solution was prepared by dissolving 15.48 g of iron nitrate hexahydrate (Fe (NO ₃ ) ₃ ˜9H ₂ O) as an iron precursor in 360 ml of distilled water. The precursor solution prepared above was mixed with 16 g of γ-Al ₂ O ₃ , stirred at room temperature and atmospheric pressure for 3 hours, and then the mixture was distilled under reduced pressure at 60 ° C. for complete drying, and then the dried product was dried with air. Fe ₂ O ₃ / γ-Al ₂ O ₃ was prepared by baking for 2 hours at about 500 ℃ while flowing the amount of supported iron to 13% by weight.

As a cobalt precursor of cobalt nitrate hexahydrate _{(Co (NO 3) 2?} 6H 2 O) 1.975 g the rear dissolved in distilled water 3.5 ㎖, then carrying the aqueous solution in the _{Fe 2 O 3 / γ-Al} 2 O 3 1.6 g This adsorbate was dried at room temperature for about a day. Next, the dried product was calcined at 500 ° C. for 2 hours while flowing air to prepare Co ₃ O ₄ / Fe ₂ O ₃ / γ-Al ₂ O ₃ having an amount of 20% by weight of cobalt supported.

Comparative example  1: iron only Supported  Preparation of the catalyst

Iron nitrate 9 hydrate as an iron precursor _{(Fe (NO 3) 3?} 9H 2 O) after the 2.171 g dissolved in distilled water 3.5 ㎖, then carrying the aqueous solution in the _{γ-Al 2 O 3 1.7 g} , room temperature, the adsorbate Dry for about a day. Next, the dried product was calcined at 500 ° C. for 2 hours while flowing air to prepare Fe ₂ O ₃ / γ-Al ₂ O ₃ having an amount of iron supported by 13 wt%.

Comparative example  2: cobalt only Supported  Preparation of the catalyst

As a cobalt precursor of cobalt nitrate hexahydrate _{(Co (NO 3) 2?} 6H 2 O) 1.481 g the rear dissolved in distilled water 3.5 ㎖, then carrying the aqueous solution in the _{γ-Al 2 O 3 1.7 g} , room temperature, the adsorbate Dry for about a day. Next, the dried product was calcined at 500 ° C. for 2 hours while flowing air to prepare Co ₃ O ₄ / γ-Al ₂ O ₃ having an amount of 15 wt% of cobalt supported thereon.

Experimental Example  1: Reducibility according to the cobalt content of the catalyst Amination  Reaction activity experiment

The catalyst prepared according to the invention was charged 0.2 g of the catalyst according to the invention prepared in Examples 1 to 4 in a fixed bed reactor operated continuously to convert it into an active state. The atmosphere in contact with the catalyst inside the reactor was maintained at 600 ° C. for 1 hour with hydrogen and then cooled to 230 ° C. Using the catalysts of Examples 1 to 4 converted to the active state, the reductive amination reaction activity experiment was performed according to the cobalt content of the catalyst under the reaction conditions of Table 1 below.

The reaction was analyzed using gas chromatography (Gas Chromatography, Chrompack, CP 9001). Here, the conversion rate of isopropylamine was calculated as in Equation 1 below, and selectivity and yield of isopropylamine and acetone were calculated using Equations 2 and 3 below (IPA: isopropyl alcohol, MIPA: monoisopropylamine). )

The results obtained by the analytical method are shown in FIG. 1 and Table 1 below.

Gas Chromatography Analysis: GC Area% Data of Components-Monoisopropylamine (GC Column: Capillary Columns-60 m Length, 0.32 mm CP-volamine, Temperature Program: 5 min at 50 ° C., 20 ° C./min, 200 Milk powder at 10 ° C).

As shown in FIG. 1 and Table 1, the catalyst according to the present invention prepared in Example 1 showed the highest yield of monoisopropylamine as 49.1% under the same reaction conditions except for the content of cobalt.

division reaction
Temperature
(℃) Isopropyl Alcohol
(ml / min) Ammo
Nya
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Conversion rate
(%) Monoisopropylamine Selectivity
(%) Acetone selectivity
(%) Monoisopropylamine yield
(%) Example 1 230 1.18 7.11 2.37 8960 92.2 53.2 44.8 49.1 Example 2 230 1.18 7.11 2.37 8960 77.0 46.6 47.7 35.9 Example 3 230 1.18 7.11 2.37 8960 91.9 52.7 44.9 48.4 Example 4 230 1.18 7.11 2.37 8960 93.7 51.2 43.1 48.0

Experimental Example  2: reducibility according to space time Amination  Reaction activity experiment

The catalyst prepared according to the present invention was activated in the same manner as in Experimental Example 1. Using the catalyst according to the present invention prepared in Example 1 was converted to the active state was carried out the experiment of the reductive amination reaction of the catalyst according to the space time under the reaction conditions of Table 2. The reaction product was analyzed using gas chromatography and the results are shown in FIG. 2 and Table 2 below. As shown in FIG. 2 and Table 2, the catalyst prepared in Example 1 showed the highest yield of 76.4% of monoisopropylamine when the space time was 49783 gmin / mmol.

Reaction temperature
(℃) Isopropyl Alcohol
(ml / min) ammonia
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Conversion rate
(%) Monoisopropylamine Selectivity
(%) Acetone selectivity
(%) Monoisopropylamine yield
(%) 230 3.16 18.95 37.89 37333 92.5 79.7 20.2 73.7 230 2.37 14.21 28.42 49783 94.2 81 18.9 76.4 230 1.84 11.05 22.11 64000 94.5 79.3 20.2 74.9 230 1.32 7.89 15.79 89600 95.0 78 20.9 74.1 230 0.79 4.74 9.47 149333 95.1 76.5 21.6 72.8

Experimental Example  3: Reducibility according to the ratio of hydrogen and alcohol Amination  Reaction activity experiment

The catalyst prepared according to the invention was charged 0.2 g of the catalyst according to the invention prepared in Example 1 into a fixed bed reactor operated continuously to convert it into an active state. The atmosphere in contact with the catalyst inside the reactor was maintained at 600 ° C. for 1 hour with hydrogen and then cooled to 230 ° C. Using a catalyst according to the present invention prepared in Example 2 converted to an active state to reduce the reaction of hydrogen and isopropyl alcohol in the reaction conditions of the following Table 3 to conduct a reductive amination reaction of the catalyst according to the hydrogen ratio Was carried out. The reaction product was analyzed using gas chromatography and the results are shown in FIG. 3 and Table 3 below. As shown in FIG. 3 and Table 3, the catalyst prepared in Example 2 increased both the conversion rate, the selectivity and the yield of monoisopropylamine as the ratio of hydrogen increased, and in particular, the yield of monoisopropylamine. Was 77.5% when the ratio of hydrogen to isopropyl alcohol was 16, and it can be seen from the above results that the yield was very high even under atmospheric pressure reaction conditions.

Reaction temperature
(℃) Isopropyl Alcohol
(ml / min) ammonia
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Conversion rate
(%) Monoisopropylamine Selectivity
(%) Acetone selectivity
(%) Monoisopropylamine yield
(%) 230 2.37 14.21 4.74 49783 68.4 47.0 52.3 32.1 230 2.37 14.21 9.47 49783 86.6 58.5 40.6 50.7 230 2.37 14.21 14.21 49783 92.2 65.2 34.1 60.1 230 2.37 14.21 18.95 49783 93.6 69.7 29.9 65.2 230 2.37 14.21 23.68 49783 94.5 72.7 26.5 68.7 230 2.37 14.21 28.42 49783 94.6 74.7 24.6 70.7 230 2.37 14.21 33.16 49783 95.2 77.5 21.7 73.8 230 2.37 14.21 37.89 49783 95.4 81.2 18.3 77.5

Experimental Example  4: reducibility according to ratio of amine compound and alcohol Amination  Reaction activity experiment

The catalyst prepared according to the present invention was activated in the same manner as in Experimental Example 1. Reductive amination reaction experiment of the catalyst according to the ammonia ratio by controlling the ratio of ammonia and isopropyl alcohol using the catalyst according to the present invention prepared in Example 1 converted to the active state Was carried out. The reaction product was analyzed using gas chromatography and the results are shown in FIG. 4 and Table 4 below. As shown in FIG. 4 and Table 4, the catalyst prepared in Example 2, the conversion, the selectivity and yield of monoisopropylamine both increased as the ratio of ammonia increased, in particular the yield of monoisopropylamine Was 86.1% when the ratio of ammonia to isopropyl alcohol was 12, and it can be seen that the yield was very high even at atmospheric pressure.

Reaction temperature
(℃) Isopropyl Alcohol
(ml / min) ammonia
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Total conversion rate
(%) Monoisopropylamine Selectivity
(%) Acetone selectivity
(%) Monoisopropylamine yield
(%) 230 2.37 0 28.42 49783 83.9 0 76.5 0 230 2.37 4.74 28.42 49783 91.4 51.4 47.4 47.0 230 2.37 9.47 28.42 49783 93.7 68.3 30.8 64.0 230 2.37 14.21 28.42 49783 94.6 74.7 24.6 70.7 230 2.37 18.95 28.42 49783 95.3 80.8 18.4 77.0 230 2.37 23.68 28.42 49783 96.4 84.4 14.9 81.8 230 2.37 28.42 28.42 49783 97.5 88.3 10.7 86.1

Experimental Example  5: reducibility according to reaction temperature Amination  Reaction activity experiment

The catalyst prepared according to the present invention was charged 0.2 g of the catalyst prepared in Example 1 to a continuously operated fixed bed reactor to convert it into an active state. The atmosphere in contact with the catalyst inside the reactor was maintained at 600 ° C. for 1 hour with hydrogen and then cooled to 150 ° C. Using the catalyst according to the present invention prepared in Example 1 was converted to the active state by controlling the temperature of the catalyst layer under the reaction conditions of Table 5 was carried out the reductive amination reaction of the catalyst according to the reaction temperature. The reaction was analyzed using gas chromatography and the results are shown in FIG. 5 and Table 5 below. As shown in FIG. 5 and Table 5, the catalyst prepared in Example 2 was continuously increased as the reaction temperature increased to 250 ℃, the selectivity of the monoisopropylamine was increased to 190 ℃ As it increased, it decreased from 210 ° C. The yield of monoisopropylamine according to the reaction temperature was highest at 210 ℃.

Reaction temperature
(℃) Isopropyl Alcohol
(ml / min) ammonia
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Conversion rate
(%) Monoisopropylamine Selectivity
(%) Acetone selectivity
(%) Monoisopropylamine yield
(%) 150 2.37 14.21 28.42 49783 30.2 86.7 13.3 26.2 170 2.37 14.21 28.42 49783 54.2 90.2 9.8 48.9 190 2.37 14.21 28.42 49783 78.2 90.3 9.7 70.6 210 2.37 14.21 28.42 49783 89.9 85.2 14.8 76.6 230 2.37 14.21 28.42 49783 94.6 74.7 24.6 70.7 250 2.37 14.21 28.42 49783 96.0 67.2 29.1 64.5

Experimental Example  6: Experiment of Decreasing Activity of Catalyst with Time

The catalyst prepared according to the invention was charged 0.2 g of the catalyst according to the invention prepared in Example 1 into a fixed bed reactor operated continuously to convert it into an active state. The atmosphere in contact with the catalyst inside the reactor was maintained at 600 ° C. for 1 hour with hydrogen and then cooled to 210 ° C. Using the catalyst according to the present invention prepared in Example 1 converted to the active state was carried out the reduction amination reaction activity reduction experiment over time under the same reaction conditions as the reaction temperature of 210 ℃ in Experimental Example 5. The reaction product was analyzed using gas chromatography and the results are shown in FIG. 6 and Table 6 below. As shown in FIG. 6 and Table 6, the catalyst prepared in Example 1 exhibited the same catalytic activity even after 200 hours of reaction time. That is, it was found that the activity of the catalyst does not decrease for a long time under the reaction conditions at atmospheric pressure.

division % Of total conversion Monoisopropylamine Selectivity (%) Acetone selectivity
(%) Monoisopropylamine
Yield (%) 0.08 h 205 h 0.08 h 205 h 0.08 h 205 h 0.08 h 205 h Experimental Example 6 90.4 91.7 85.7 85.5 14.1 14.4 77.5 78.4

Experimental Example  7: Catalytic Activity Experiment of Comparative Catalyst

0.2 g of the catalyst prepared in Comparative Examples 1 and 2 were charged. The atmosphere in contact with the catalyst inside the reactor was maintained at 600 ° C. for 1 hour with hydrogen and then cooled to 230 ° C. Using the catalysts of Comparative Examples 1 and 2 converted to the active state, the reductive amination reaction of iron was carried out under the reaction conditions of Table 7 below. The reaction product was analyzed using gas chromatography and the results are shown in Table 7 below. The Fe ₂ O ₃ / γ-Al ₂ O ₃ catalyst having an amount of supported iron of Comparative Example 1 of 13% by weight has a low conversion rate, monoisopropylamine selectivity and yield of 60% or less, but the activity of the catalyst is reduced. Turned out not to. In addition, the Co ₃ O ₄ / γ-Al ₂ O ₃ catalyst having an amount of 15 wt% of the cobalt supported in Comparative Example 2 showed a high conversion rate, but the activity of the catalyst rapidly decreased with time. This can be confirmed that compared with the results of Experimental Example 1 is a significantly lower level of catalytic activity.

division Reaction temperature
(℃) Isopropyl Alcohol
(ml / min) ammonia
(ml / min) Hydrogen
(ml / min) Space time
(gmin / mmol) Conversion rate
(%) Monoisopropylamine Selectivity
(%) Monoisopropylamine yield
(%) Comparative Example 1 230 1.18 7.11 2.37 8960 54.9 36.5 20.0 Comparative Example 2 230 1.18 7.11 2.37 8960 79.7 40.4 32.2

Claims (15)

delete delete delete delete A catalyst for reductive amination of alcohols in which cobalt and iron are supported in an amount of 5 to 20% by weight relative to the total weight of the catalyst on an alumina, silica or alumina-silica support having a specific surface area of 150 to 300 m ² / g.
The aqueous cobalt precursor solution and the iron precursor aqueous solution are impregnated simultaneously or sequentially in an alumina, silica or alumina-silica support having a specific surface area of 150 to 300 m ² / g, wherein the cobalt and iron contents are respectively 5 to about the total weight of the catalyst. Impregnating and stirring to 20% by weight, followed by drying and calcining.
The method of claim 6, wherein the cobalt precursor is cobalt chloride, cobalt acetate, cobalt nitrate, or a mixture thereof.
The method of claim 6, wherein the iron precursor is ferric chloride, ferric sulfate, iron nitrate or a mixture thereof.
The method of claim 6, wherein the firing temperature is 400 ~ 600 ℃ the method for producing a catalyst for the reductive amination reaction of alcohol.
Mixing the alcohol and the amine compound at a pressure below atmospheric pressure to form an amination reaction mixture;
Contacting hydrogen with the catalyst of claim 5 to activate the catalyst; And
Contacting the activating catalyst with the amination reaction mixture to produce an alkylamine.
The method of claim 10, wherein the alcohol is isopropyl alcohol, the amine compound is ammonia, and the alkylamine is monoisopropylamine.
The method of claim 10, wherein the volume ratio of alcohol and hydrogen is 1: 1 to 20, characterized in that the alkylamine production method.
The process for producing an alkylamine according to claim 10, wherein the volume ratio of the alcohol and the amine compound is 1: 1 to 15.
The method of claim 10, wherein the space time in the reaction is 30000 to 50000 gmin / mmol.
The method of claim 10, wherein the temperature in the reaction is 180 to 240 ℃ manufacturing method of alkylamine.

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