JPS6220978B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a process for producing amines by reacting alcohols or aldehydes with ammonia, primary or secondary amines in the presence of a catalyst in a reducing atmosphere, and to amines produced by this process. Many catalyst materials have been disclosed in the prior art for producing amines from alcohols. GB Patent Specification No. 436,414 discloses a number of catalysts, typically copper-containing hydrogenation catalysts, useful for the production of amines from alcohols. US Patent Specification No.
No. 3,128,311 discloses the reaction of alcohol and ammonia in the presence of nickel, copper and a catalyst containing chromium oxide, titanium oxide, thorium oxide, zinc oxide or manganese oxide. US Patent No.
No. 3,520,933 discloses a number of metal and alkaline additives, such as copper, useful in the conversion of alcohols to amines when used in combination with pyro acids or multiple acids. None of the prior art disclosures suggests that the particular combination of copper and tin of the present invention produces a synergistic effect resulting in increased selectivity or catalyst stability. Thus, the present invention provides a process for producing amines by reacting alcohols, aldehydes or ketones having up to 25 carbon atoms with ammonia or primary or secondary amines having 1 to 8 carbon atoms in a reducing atmosphere, 0.05-50 supported on porous carrier
The process is characterized in that the reaction is carried out in the presence of a catalyst containing % by weight of copper and 0.05-50% by weight of tin. The catalyst of the present invention is used by being supported on a suitable carrier. The weight percent of copper (basic copper metal relative to total catalyst weight) is 0.05% w - 50% w, more preferably 0.5%
w - 20% w. The weight percent of tin (basic tin metal relative to total catalyst weight) is 0.05%w-50%w, more preferably 0.5%w-20%w. The weight percent of alkali or alkaline earth metals, if present, is
0.003-30%w, preferably 0.01-10%w.
Catalysts may be used in the form of oxides, metals or mixtures thereof. Alkali and alkaline earth metals are group A and A metals of the periodic table and salts of these metals,
For example, it is provided as lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, potassium and barium salts. Sodium salts are preferred. Supports suitable for the process of the invention are selected from porous, heat-resistant conventional supports that are resistant under the reaction conditions to the starting materials and reaction products used in the reaction. The carrier may be natural or synthetic. Very suitable supports include siliceous and/or alumina compositions. Particular examples of suitable carriers are aluminum oxide, charcoal, pumice, magnesium, zirconia, diatomaceous earth, Fuller's earth, silicon carbide, silica and/or porous aggregates containing silicon carbide, clays, artificial and natural zeolites,
Ceramics, etc. Particularly useful refractory supports for the preparation of catalysts are siliceous and/or aluminous materials, especially those containing gamma-alumina. The catalyst can be prepared in a number of suitable ways, for example by co-precipitating the metal component onto a powder or pellet support or by co-precipitating the support from an aqueous solution with, for example, sodium carbonate or sodium hydroxide. A preferred method is to impregnate the support with a solution of a suitable salt of the active metal, then dry and calcinate the impregnated support at 100°C-600°C. The preferred solvent is water, although certain organic solvents may also be suitable. Useful salts for aqueous systems are chloride, bromide, nitrate, acetate or lactate. Alkali metal stannites and stannites are particularly useful in providing both tin and alkali metals. Alternatively, a solution of the active metal salt and carrier can be heated to 100℃-600℃.
It is also possible to spray dry and bake. The catalyst used in the present invention can be activated by heating in a reducing atmosphere, such as a hydrogen or ammonia atmosphere, before use. The preferred atmosphere is hydrogen. The activation temperature is 250°C to 600°C, and the time required for activation depends on the temperature; the higher the temperature, the shorter the time. Typically, useful times have been found to be between 0.1 hours and 24 hours, although times outside this range are also useful, but this range is preferred for economic reasons. Suitable reactant hydrocarbon materials are aliphatic, cycloaliphatic or aliphatic alcohols or aldehydes having 25 and preferably up to 20 carbon atoms.
These starting materials are unsaturated, e.g.
may have two olefinic double bonds. They may also contain substituents which are inert under the reaction conditions, for example a C1-4 alkyl group attached via an ether bridge. Aliphatic or cycloaliphatic alcohols having up to 20 carbon atoms are of particular industrial importance. Examples of suitable alcohols/aldehydes include ethanol/ethanal, propanol/propanal, isopropanol, butanol/butanal, isobutanol/isobutanal, 2-ethylhexanol/2-ethylhexanal, decanol/decanal, dodecanol/dodecanal, hexadecanol. /hexadecanal, cyclopentol, cyclohexanol, cyclo-octanol, cyclododecanol, benzyl alcohol/benzyl aldehyde, phenylethyl alcohol/phenylethyl aldehyde, 1,4-
Butanediol/1,4-butanedial, 1,
6-hexanediol/1,6-hexanediol, 1,5-pentadiol/1,5-pentadiol and 1,8-octanediol/1,8
-Octanedial is an example. Suitable reactant amine materials are primary or secondary amines. Alkylamines having 1-12 carbon atoms,
Preference is given to cycloalkylamines or aralkylamines, especially those having from 1 to 4 carbon atoms and one amine group in the molecule. Examples of suitable amines are monomethylamine, dimethylamine, methylethylamine, monoethylamine and diethylamine. Preferred reactant amines are monomethylamine and dimethylamine. It is advisable to react the reactant alcohol or aldehyde with at least an equivalent amount of ammonia or reactant amine and to use an excess amount, e.g. per reactant hydroxyl or carbonyl group.
It is also expedient to use up to 50 mol, preferably 20 mol, of ammonia or reactant amine. It is advisable to carry out the reaction at 160°C-350°C. The preferred temperature is 180°C-300°C. The reaction pressure is preferably 1-275 bar (100-27500kPa)
10-70 bar. Preferably, the reaction is carried out in the presence of hydrogen. 1-200 bar preferably 5
It is advisable to use a hydrogen partial pressure of -70 bar.
It is advisable to have a molar ratio of hydrogen to alcohol, aldehyde or ketone greater than 1. The reaction system may be partially pressurized with an inert gas such as nitrogen, argon. The reaction can be carried out batchwise or in continuous operation. For example, in a batch process, a stirred autoclave may be charged with alcohol, aldehyde or ketone, amine or ammonia and catalyst, pressurized with hydrogen, and heated to reaction temperature. After continuing the reaction for the desired time, the autoclave is cooled, excess hydrogen is removed, and the product is worked up in conventional manner. In the case of a continuous process, for example, a vertical high-pressure column is packed with a catalyst and the alcohol and reactant amine are fed from the top. At the same time, hydrogen is metered into the column in co-current or counter-current flow. It is a good idea to circulate hydrogen. Maintain appropriate temperature and pressure conditions during the reaction. The reaction product is removed from the bottom, freed from hydrogen and worked up in conventional manner. In an alternative continuous method, the catalyst-dispersed reaction mixture is allowed to drip onto packing or baffles within the column. The invention is further illustrated by the following example. Example 1 (Catalyst Preparation Method) A solution obtained from 16 g of copper nitrate Cu(NO ₃ ) _{2.3H 2} O and 15 ml of H ₂ O was mixed with 45 g of 18×30 mesh alumina (surface area 263 m ² /g, Pore volume 0.26ml/g)
It was used for impregnation. Impregnation was carried out with thorough mixing to ensure that the salt was evenly distributed on the alumina. The impregnated alumina is placed in a vertical tube and the temperature is increased within 30 minutes.
80℃, 100℃, 125℃, 150℃, 175℃, 200℃, 250
Air was passed over the impregnated alumina at a rate of 400 ml/min while gradually increasing the temperature in the order of 300°C, 400°C and 500°C. Cool the calcined material to room temperature and add to 18 ml _H2O .
It was impregnated with a solution containing 3 g of sodium stannate. The above calcination step was repeated and the catalyst was then reduced stepwise with a hydrogen gas mixture diluted with nitrogen at 125-500°C for 2 hours. Example 2 45 g of Reynolds RA-1 alumina (18 x 30 mesh, surface area approximately 260 m ² /g, pore volume approximately 0.26
The catalyst was prepared by impregnating a solution of 16 g of copper nitrate in 16 ml of _H2O . The material was calcined as above and mixed with 1 ml of H ₂ O and 1
It was re-impregnated with a solution of stannous tartrate in ml of _HNO3 . The reimpregnated material was calcined and reduced as in Example 1. The catalyst (10 ml) was charged to a trickle phase reactor with a liquid hourly space velocity (LHSV) of 1.1 and a molar ratio of dimethylamine to lauryl aldehyde of 3:1. The reactor was kept at 180°C. 100 hydrogen
It was introduced into the reactor at a rate of ml/min and the pressure was maintained at 26 bar. After 1 hour of operation, the conversion (mol) of aldehyde was 98.9% and the selectivity (mol) to dimethyldodecylamine was 77.3%. After 2 hours of operation, the conversion was 100% and the selectivity was 70%. Example 3 A solution obtained by heating 4.6 g of copper nitrate and 20 ml of NH ₄ OH and then adding 1 g of sodium stannate was added to 48 g of Reynolds RA-1 alumina (18 x 30 mesh). The catalyst was prepared by impregnation. This material was calcined and reduced as in Example 1. The catalyst is 2.4% w Cu, 0.71% w Sn and 0.7
Contains %w Na. A trickle phase reactor with a volume of 25 ml was charged with catalyst (10 ml) and dimethylamine and dodecanol were fed to the reactor at a LHSV of 1.1 and a molar ratio of amine to alcohol of 3:1. The reactor was maintained at approximately 250°C. Hydrogen was fed to the reactor at a rate of 100 ml/min and the pressure was maintained at 26 bar. 2.5
The molar conversion rate of alcohol after operation for hours is 95.4%
and the molar selectivity to dimethyldodecylamine is
It was 78%. Example 4 A catalyst was prepared by impregnating 30 g of Reynolds RA-1 alumina with a solution prepared by dissolving 2 g of copper nitrate in 15 ml of NH ₄ OH and adding 0.5 g of sodium stannate. The catalyst was calcined and reduced as in Example 1. The catalyst was 4% w Cu, 1.2% w Sn and
Contains 0.87%w Na. A trickle reactor with a volume of 25 ml was charged with catalyst (10 ml) and dimethylamine and 1-
Dodecanol was fed to the reactor at a LHSV of 1.1 and an amine to alcohol molar ratio of 1.4:1.
The reactor temperature was maintained at 244°C. Hydrogen was fed to the reactor at a rate of 100 ml/min and the pressure was maintained at 26 bar.
After 1.5 hours of operation, the molar conversion of alcohol is
The molar selectivity to dimethyldodecylamine was 60.3% and 94%. The reactor temperature was raised to 250°C and after 1.5 hours the conversion was 79.1% and the selectivity to dimethyldodecylamine was 89.4%.
After 2.5 hours of operation, the molar conversion of alcohol is
The molar selectivity to dimethyldodecylamine was 82% and 88.9%. The same catalyst was used, but dimethylamine, trimethylamine and 1-dodecanol were used in a molar ratio of 3:
By repeating the above procedure feeding at a ratio of 2,3:1, a conversion of 89.7% and a selectivity to dimethyldodecylamine of 85.7% was obtained after 2.5 hours of operation. Example 5 A solution of 1.5 g of sodium stannate dissolved in 10 ml of H ₂ O was added to 24 g of 18×30 mesh of Al ₂ O ₃ (RA-1) and calcined and reduced as in Example 1. This is 2.9
Contains %w Sn and 0.9%w Na. A trickle phase reactor with a volume of 25 ml was charged with catalyst (10 ml) and dimethylamine and 1-dodecanol were fed to the reactor at a LHSV of 1.1 and a molar ratio of amine to alcohol of 3:1. Hydrogen was fed to the reactor at a rate of 100 ml/min and the pressure was maintained at 26 bar. No alcohol conversion was observed at a reactor temperature of 257°C. 300℃ (1
The molar conversion rate of alcohol is 9% under
It was distributed almost equally between methyldodecylamine and dimethyldodecylamine. Example 6 A catalyst was prepared as in Example 1. Catalyst is 7.6
It contained %w Cu, 2.7%w Sn and 0.9%w Na. Trickle phase reactor (25ml volume) with catalyst (25ml)
Filled with dimethylamine and 1-dodecanol.
A LHSV of 0.6 and a molar ratio of amine to alcohol of 3:1 were fed to the reactor. Hydrogen was fed to the reactor at 180 ml/min and the pressure was maintained at 28 bar. The results were as shown in the table below.

Table: Example 7 A catalyst was prepared as in Example 1. Catalyst is 8.3
It contained %w Cu, 2.3%w Sn and 1%w Na. The catalyst (10 ml) was charged into a trickle phase reactor with a volume of 25 ml, and dimethylamine and n-butanol were added.
A LHSV of 1.1 and a molar ratio of amine to alcohol of 3:1 were fed to the reactor. hydrogen to reactor
The pressure was maintained at 26 bar by feeding at a rate of 100 ml/min. After a reactor temperature of 250 DEG C. and 1 hour of operation, the alcohol conversion was 68.8% and the selectivity to dimethylbutylamine was about 100%. After 1 hour at 273℃, the conversion rate was 93.4%m, and the selectivity was
It was larger than 99% m. Example 8 To 25 g of Reynolds RA-1 alumina (18 x 30 mesh) was added 8 g of copper nitrate in 4 ml of H ₂ O and then 1.1 g of copper nitrate in 3 ml of H ₂ O and 1 ml of HNO ₃ . It was impregnated with a solution containing stannous tartrate. This material was calcined and reduced as in Example 1. This is 5.4% w Cu, 1.5% w Sn and 0.5% w
Contains Na. This catalyst was designated as A. The above procedure was repeated using slightly different concentrations. The catalyst was 9.3% w Cu, 1.6% w Sn and
Contains 0.3%w Na. This catalyst was designated as B. Catalyst (10 ml) was individually charged into a trickle phase reactor (25 ml). Monomethylamine and 1-dodecanol were fed in a 3:1 molar ratio. LHSV was 1.1. Hydrogen was fed to the reactor at a rate of 100 ml/min and the pressure was maintained at 26 bar. The results were as shown in the following table.

Table: Example 9 A number of catalysts were prepared as in Example 1. The catalyst had the following composition. _The support was _Al2O3 .

Table Catalysts were individually packed into a trickle phase reactor. Methylamine and 1-dodecanol in a molar ratio of 3:1 and
Supplied in LHSV1.1. Hydrogen was fed to the reactor at a rate of 100 ml/min and the pressure was maintained at 26 bar. The results were as follows.

[Table] Example 10 1.1 g of stannous tartrate dissolved in 1 ml of H ₂ O + 1 ml of HNO ₃ and 16 g of copper nitrate dissolved in 16 ml of H ₂ O are combined to produce 45 g of Al ₂ O ₃ ( It was used for impregnation of RA-1). This material was fired as in Example 1.
This is 7.1% w Cu, 0.94% w Sn and 0.4% w
Contains Na. The catalyst was charged into a trickle phase reactor and ammonia and 1-dodecanol were fed to the reactor in a molar ratio of 3.5:1 and LHSV of 1.1. 100 hydrogen
ml/min to the reactor and the pressure was maintained at 26 bar. The results were as shown in the table below.

[Table] Example 11 7.6%w Cu, 3.1%w Sn and 1.6%w Na
Example 10 was repeated using a catalyst containing: Ammonia and 1-dodecanol were supplied at a molar ratio of 1.5:2. The results were as follows.

【table】

Claims (1)

[Scope of Claims] 1. A process for producing an amine by reacting an alcohol or aldehyde having up to 25 carbon atoms with ammonia or a primary or secondary amine having 1 to 8 carbon atoms in a reducing atmosphere, comprising: 0.05-50 wt% copper supported on and 0.05-50
A process characterized in that the reaction is carried out in the presence of a catalyst containing % by weight of tin. 2 Claim 1 in which the carrier is alumina
Manufacturing method described in section. 3. The method according to claim 1 or 2, wherein copper is 0.05-20% by weight and tin is 0.5-20% by weight based on the total catalyst weight. 4 Catalyst additionally 0.003 to total catalyst weight
- 30% by weight of an alkali or alkaline earth metal. 5 Alkali or alkaline earth metal is 0.01-10
The manufacturing method according to claim 4, which is % by weight. 6. The manufacturing method according to any one of claims 1 to 5, wherein the reducing atmosphere is hydrogen. 7. Process according to any one of claims 1 to 6, wherein the reaction pressure is 1 to 275 bar. 8. The production method according to any one of claims 1 to 7, wherein the reaction is carried out at 160°C to 350°C.