JPS63126558A - Catalyst for vapor phase intramolecular dehydration reaction of alkanol amines - Google Patents

Abstract

PURPOSE:To convert alkanol amines to cyclic amines at a high yield by using a catalyst consisting of lanthanoid elements and/or actinoid elements, alkali metals and/or alkaline earth metals and specific bond of P, O. CONSTITUTION:The titled catalyst is constituted of the catalyst compsn. expressed by the formula XaPbYcOd (X denotes 1 or more kinds of elements selected from the lanthanoid elements and/or actinoid elements of periodic table, Y denotes the alkali metals and/or alkaline earth metals a-d denote atomic ratios of the respective element, b=0.01-6, c=0.001-3 when a=1, d is the numerical value determined by the bonding condition of a-c and various constituting elements). The alkanol amines expressed by formal I (R, R' are selected from H, methyl groups and ethyl groups, n is an integer in a 2-5 range) are highly selectively converted to the cyclic amines expressed by formula II (R, R' are the same as in formula I) at a high yield stably for a long period time.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a novel method for converting alkanolamines represented by the general formula (I) into cyclic amines represented by the general formula (I). This invention relates to a catalyst for gas phase intramolecular dehydration reaction.

RR (wherein R, R' are each selected from the group consisting of hydrogen, methyl group, and ethyl group, and n is an integer in the range of 2 to 5.) The cyclic amines represented by (It) above are Generally, since it is highly reactive and reacts with compounds having various functional groups, various derivatives having amino groups can be produced. Furthermore, since a ring-retaining reaction is also possible, derivatives having ring-opening reactivity can also be produced. Furthermore, polyamine-based polymers can also be produced by ring-opening polymerization reaction, making it a highly useful compound. Derivatives of cyclic amines are very useful compounds that are widely used in various industries as IIIi processing agents, antistatic agents, pharmaceuticals, agricultural chemical raw materials, and the like. The present invention provides a high-performance catalyst for use in producing cyclic amines, which are such useful compounds, by intramolecular dehydration reaction of alkanolamines in the gas phase, which is extremely advantageous in terms of productivity. It is something.

[Prior Art] Methods for converting alkanolamines into cyclic amines by dehydration include a method of intramolecular ring-opening of a halogenated amine with a concentrated alkali (Gabriel method);
A method of ring-closing alkanolamines with hot concentrated alkali (Wenker method) is known, but these methods use a large amount of alkali in the form of a concentrated solution, resulting in low productivity, and the amount of alkali in the raw material cost is low. There are many problems from an industrial perspective, such as the large amount of oxidation and the production of a large amount of inorganic salts with low utilization.

In recent years, in contrast to the liquid phase method described above, monoethanolamine is used as the alkanolamine, and this is dehydrated in the gas phase in the presence of a catalyst to continuously produce the corresponding cyclic amine, ie, ethyleneimine. Several attempts at manufacturing have been reported. As an example of these, for example,
No. 10593 describes a method using a tungsten oxide catalyst, and US Pat. No. 4,301,
No. 036 Akira mml further describes a method using a catalyst consisting of tungsten oxide and silicon, as disclosed in U.S. Patent No. 4,28
No. 9, 656, No. 4,337, 175, No. 4
, Nos. 477 and 591, each specification 11 discloses a method using a niobium or tantalum catalyst.

[Problems to be Solved by the Invention] However, in any of the methods using the above-mentioned catalysts, the conversion rate of monoethanolamine is low, and the conversion rate is relatively low.
Even in the case where ethyleneimine is removed, the selectivity for ethyleneimine is low because the proportion of products resulting from side reactions such as deammonification and dimming reactions is low. Furthermore, according to the studies conducted by the present inventors, when it comes to the life of the catalyst, in any case, the activity decreases significantly in a short period of time, and from an industrial point of view,
It's not completely satisfying.

The present invention is to produce target cyclic amines with high selectivity and high yield, and moreover, stably over a long period of time in performing a gas phase intramolecular dehydration reaction of alkanolamines.

[Means for Solving the Problems] As a result of intensive research by the present inventors on catalysts for gas phase intramolecular dehydration reactions of alkanolamines, the general formulas X8P, Y
CO, (wherein, One or more selected elements, P represents phosphorus, O represents oxygen. Subscript a
, b, c, d indicate the atomic ratio of each element,
When ai, b - 0.01 to 6 (preferably 0.
05-3), C-0.001-3 (preferably 0,
d t, t a, b, c
and a numerical value determined by the bonding state of various constituent elements. ) By using the catalyst composition represented by the formula, the gas phase intramolecular dehydration reaction of alkanolamines proceeds extremely favorably, and the target cyclic amines can be produced highly selectively and in high yields, and also stably for a long period of time. The inventors have discovered a scale that can be manufactured in the following manner, and have completed the present invention.

X is one or more elements selected from lanthanide group elements and/or actinide group elements in the periodic table, and examples of such elements include:
Examples include elements such as La, Ce, Eu, and Th. Further, Y is one or more elements selected from alkali metals and/or alkaline earth metals, and examples of such elements include Li, Na, and Rb.

Examples include elements such as Cs, MQ, Ca, Sr, and 8a.

The alkanolamines used as reaction raw materials have the general formula (
Alkanolamines represented by I) are preferred;
According to the present invention, these amines can be converted into cyclic amines represented by general formula (II) with high conversion rate and high selectivity.
And it is converted stably over a long period of time. Examples of the alkanolamines include (a) monoethanolamine, (
b) Isopropanolamine, (C) 3-amino-1
-propanol, (d) 5-amino-1-pentanol, (e) 2-amino-1-butanol, and the like, but are not limited to these. The cyclic amines obtained corresponding to these amines are each (a
') Ethyleneimine, (b-) 2-methyl-ethyleneimine, (a') azetidine, (d-) piperidine, (e
') 2-ethyl-ethyleneimine.

Raw materials for the X component and Y component include respective oxides, hydroxides, halides, salts (carbonates, sulfates, nitrates, etc.) and metals, and phosphorus sources include orthophosphoric acid, pyrophosphoric acid, Various phosphoric acids such as metaphosphoric acid, phosphorous acid, and polyphosphoric acid, phosphorus pentoxide, and salts of the above-mentioned phosphoric acids (ammonium phosphate, potassium phosphate, sodium phosphate, etc.) are used. Note that phosphates of the X component and the Y component may be used as the source of the X component, the source of the Y component, and the phosphorus source.

The method for preparing the catalyst according to the present invention is not particularly limited, and the commonly used 1m production method is used.

For example, ■ A method of dissolving or suspending various catalyst raw materials of component X, component Y, and phosphorus in water, heating and concentrating with stirring, drying, molding, and further calcination to form a catalyst, ■
Dissolve the components and the raw materials for the Y component in water, add various phosphoric acids or various phosphates, adjust the pH as necessary, filter, wash with water, dry, mold, and calcinate to make a catalyst. Method or ■ Mix various phosphoric acids or various phosphates to the oxides or hydroxides of each component element, add appropriate molding aids (e.g. water, alcohol, etc.), mold, dry, Examples include a method of converting it into a catalyst through calcination.

Further, the catalyst according to the present invention may be supported on a known inert carrier (for example, Celite (trade name), silica gel, silicon carbide, alumina, etc. are preferable, but not limited to these). can.

The firing temperature of the catalyst of the present invention may vary widely from 300°C to 1500°C, preferably from 400°C to 1200°C, although it depends on the type of raw materials used.

In carrying out the present invention, either a fixed bed flow type reactor or a fluidized bed type reactor can be used. The raw material alkanolamines are used after being diluted with an inert gas such as nitrogen, helium, or argon to a concentration of 1 to 80% by volume, preferably 2 to 50% by volume, if necessary. Further, in some cases, ammonia, water, or the like may be supplied together with alkanolamines for the purpose of suppressing side reactions. The reaction is usually carried out at normal pressure, but it can also be carried out under increased or reduced pressure if necessary. The reaction temperature varies depending on the type of raw material and varies from 250 to 600℃.
℃ range. The space velocity of the raw material gas varies depending on the type of raw material and the raw material gas temperature, but it is 100 to 40,00
Ohr (STP), preferably 500-20.
A range of 000 hr-' (STP) is suitable.

[Operations and Effects of the Invention] When the catalyst of the present invention is used in the gas phase intramolecular dehydration reaction of alkanolamines, it exhibits extremely high activity compared to conventionally known catalysts, and has a high selectivity to the target cyclic amine. was also significantly high.

Moreover, even if this reaction is carried out continuously for a long time,
No deterioration of catalyst activity was observed, and both activity and yield were extremely stable, and the problem of overcoming short-term deterioration, which is important for industrialization, could be fully solved.

The catalytic performance was evaluated using a known catalyst for ethyleneimine synthesis from monoethanolamine (for example, Japanese Patent Publication No. 50-105
93 and U.S. Pat. No. 4,337,175 (WO-8iO and Nb 0-Ba O composition catalyst), the performance of the catalyst according to the present invention was found to be lower in both activity and selectivity. , which significantly exceeded their catalytic performance.

Although the details of the reason why the catalyst of the present invention exhibits excellent performance in the gas-phase dehydration reaction from alkanolamines to cyclic amines are not clear, there are acidic points and basic points on the catalyst surface. This is thought to be due to their concerted action. It is believed that the X component controls the acid strength of the acidic sites caused by phosphoric acid, and also generates basic sites, forming a surface condition of the catalyst suitable for this reaction. The Y component further finely controls the acidic and basic sites on the surface and further improves the selectivity of the target cyclic amine. The reaction progresses effectively through acid-base cooperation, and at the same time, the desorption of products is smooth, and deactivation due to poisoning of strongly adsorbed substances on the catalyst is suppressed, which is the same as in conventional catalysts. It is believed that this method solves the phenomenon of decrease in selectivity due to improvement in conversion rate, and can produce the target cyclic amine with high conversion rate and high selectivity, and extremely stably over a long period of time.

[Examples] Hereinafter, the present invention will be specifically described in Examples, and the conversion rate, selectivity, and single flow yield in the Examples shall comply with the following definitions.

Conversion rate (mol %) - Number of moles of alkanolamine consumed Selectivity (mol %) - Number of moles Single stream yield (mol %) - Number of moles Example 1 Cerium oxide 49. 2 g of the suspension was suspended in 1 ml of water, 34.6 g of 85% overheated orthophosphoric acid was added, and the mixture was heated and concentrated with sufficient stirring, followed by evaporation to dryness on a hot water bath. After drying this in the air at 120℃ overnight, it was dried at 600℃ in the air.
It was baked for 2 hours to form a solid product. A solution of 12 g of sulfur and lithium hydroxide dissolved in 40 parts of water was added to this solid, evaporated to dryness on a hot water bath, and dried overnight at 120°C.
It was crushed into mesh and calcined at 500'C for 2 hours to obtain a catalyst.

This catalyst 20II! i2 is the inner diameter of 16. After filling a stainless steel reaction tube, the tube was immersed in a molten salt bath at 430°C, and a raw material gas having a volume ratio of monoethanolamine:nitrogen of 5:95 was passed through the tube at a space velocity of 3000 hr' (STP) to complete the reaction. I did it. The reaction was carried out continuously, and the products were quantitatively analyzed by gas chromatography at 2 hours and 50 hours after the start of the reaction, and the results are shown in Table 1.

Example 2 A catalyst 5I was prepared in the same manner as in Example 1, except that 79.2 g of thorium oxide was used instead of cerous oxide. Using this catalyst, monoethanolamine and isopropanolamine were reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-1.

Example 3゜130.3g of lanthanum nitrate (hexahydrate) in 300m of water
Dissolve 44.7 g of triammonium phosphate in 300 g of water.
The solution in m1 was added with stirring. After filtering and washing the obtained precipitate with water, a solution of 22.5 Q of cesium hydroxide dissolved in 20 d of water was added, kneaded well, dried overnight at 120°C, crushed into 9 to 5 meshes, and heated to 800°C. It was calcined for 2 hours and used as a catalyst. Using this catalyst, monoethanolamine and 3-amino-1-butanol were reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-1.

Example 4 Cerium nitrate (
hexahydrate) 117.3a and europium chloride 6,
69g, potassium hydroxide 8, instead of cesium hydroxide
A catalyst was prepared in the same manner as in Example 3, except that 4 g of barium hydroxide (octahydrate) and 9.5 g of barium hydroxide (octahydrate) were used. Using this catalyst, monoethanolamine, 3-amino
-1-Butanol and 5-amino-1-pentanol were reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-1.

Example 5゜Cerous oxide 24, 6Q instead of cerous oxide
A catalyst was prepared in the same manner as in Example 1 except that 39.6 (J) and thorium oxide were used. Using this catalyst, a reaction was carried out with monoethanolamine in the same manner as in Example 1. Reaction conditions and The results are shown in Table-1.

Comparative Example 1 A silicon carbide carrier of 601 was added to 100 g of a 30% by weight aqueous orthophosphoric acid solution, and the support was evaporated on a hot bath. This is 12
After drying at 0°C overnight, it was calcined at 450°C for 2 hours to obtain a catalyst. Using this catalyst, monoethanolamine and 2-amino-1-butanol were reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-2.

Comparative Example 2 49.2 iJ of cerium oxide was suspended in 100 d of water, 34.6 Q of 85% by weight orthophosphoric acid was added, and the suspension was concentrated by heating with thorough stirring, and evaporated to dryness on a hot bath. After drying this in air at 120°C overnight, it was crushed into 9 to 5 meshes and calcined at 600°C for 2 hours to obtain a catalyst. Using this catalyst, monoethanolamine was reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-2.

Comparative Example 3 A catalyst was prepared in the same manner as Comparative Example 2, except that 79.29 g of thorium oxide was used instead of cerous oxide. Example 1 for monoethanolamine using this catalyst
The reaction was carried out in the same manner. Table 2 shows reaction conditions and results.
It was shown to.

Comparative Example 4 40 (l) of silicon carbide having a diameter of 5III was soaked in 65.2° ammonium metatungstate aqueous solution (50% by weight based on W03) and evaporated to dryness on a hot bath. This was heated in air at 150°C for 1 hour. A catalyst precursor was obtained by drying and calcining at 715°C for 4 hours.This was immersed in 10% silicon oxide colloidal solution 501 and evaporated to dryness on a hot bath.Furthermore, it was dried in air at 150°C for 1 hour. After that, it was fired at 715°C for 4 hours to obtain 25.4% by weight of tungsten oxide and 3% by weight of silicon oxide.
．． Supported catalyst containing 3% by weight (atomic ratio W to SiO
, 50a, t > is 1q. Using this catalyst, monoethanolamine was reacted in the same manner as in Example 1. The reaction conditions and results are shown in Table-2.

Note that this catalyst was prepared according to Example 4 described in US Pat. No. 4,301,036.

Comparative example 5゜niobium pentoxide 5. After Og was completely dissolved in 50 ml of water while heating at 60°C, ammonium water was added to adjust the pH of the solution to 7.0. The generated precipitate was filtered, washed with water, and then dissolved in 80 ml of a 10% oxalic acid aqueous solution.
Furthermore, 0.2 (l) of barium hydroxide (octahydrate) was added. Silicon carbide EOCC was immersed in this solution and heated to 80°C.
After evaporation to dryness, the supported catalyst (Nb1. in atomic ratio) was calcined in air at 500° C. for 3 hours to form a supported catalyst containing 3.7% by weight of niobium pentoxide and 0.5% by weight of barium oxide.

lea O, 102, 6) was obtained. Using this catalyst,
A reaction was carried out in the same manner as in Example 1 using monoethanolamine. The reaction conditions and results are shown in Table-2.

Note that this catalyst was prepared according to Example 3 described in US Pat. No. 4,477.591.

Procedural amendment (voluntary) June 1986
29th of the month

Claims (1)

[Claims] (1) General formula Y is one or more elements selected from alkali metals and/or alkaline earth metals, P is phosphorus, and O is oxygen. Subscript a, b, c, d indicate the atomic ratio of each element,
When a=1, b=0.01-6, c=0.001-3
d is a value determined by the bonding state of a, b, c and various constituent elements. ), there are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ (I) (in the formula, R and R' are each selected from hydrogen, methyl group, and ethyl group). (n takes an integer value ranging from 2 to 5.)
Alkanolamines represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) (In the formula, R, R' and n are the same as in the above formula (I).) Cyclic amines Catalyst for gas phase intramolecular dehydration reaction that converts into