JPH07316089A - Production of carbonyl compound - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high yield, by using a specific modified Raney copper catalyst showing high performances, high particle strength and excellent filtering characteristics prepared by a simplified method having reproducibility, as a catalyst. CONSTITUTION:In producing the objective compound by dehydrogenating a primary alcohol or a secondary alcohol, a modified Raney nickel catalyst obtained by dissolving out a ternary alloy containing Cu, Al and Fe is used as a catalyst. A catalyst having the composition of Al and Fe in the catalyst as atomic ratios of Al to Cu of 0.02 to 0.20 and Fe to Cu of 0.01 to 0.35 is preferably used.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a carbonyl compound. More specifically, the present invention relates to a method for producing a corresponding carbonyl compound by dehydrogenating a primary alcohol or a secondary alcohol.

[0002]

BACKGROUND OF THE INVENTION Carbonyl compounds such as aldehydes and ketones are usually produced by dehydrogenating a corresponding primary alcohol or secondary alcohol. Conventionally, PdCl ₂ / Cu (NO ₃ ) ₂ , Pt, Ag, as a catalyst used for the dehydrogenation reaction of alcohol,
Ni, Cu, Cu / Zn, Cu / Cr, Cu / Cr
Metal oxides such as / Ba have been proposed. For example, JP-A-60-258135 discloses Raney nickel as a catalyst for producing acetone and methyl ethyl ketone by dehydrogenation reaction, and JP-A-56-20 as a catalyst for producing cyclohexanone by dehydrogenation reaction of cyclohexanol.
541 is a Cu / Cr oxide system, JP-A-58-1577.
41 is a Cu / Cr / K oxide system, JP-A-61-282
334 discloses a catalyst prepared by adding an alkali metal oxide to a Cu / Zn oxide system.

However, considering the yield and selectivity of the carbonyl compound as a product, the dehydrogenation of alcohol with a Cu-based catalyst is an important industrial process for producing carbonyl compounds. In particular, Cu / Cr oxides, usually called copper-chromite catalysts, are generally used as industrial catalysts. The method for producing this copper-chromite catalyst is described in Industrial and Engineering Chemistry, No. 2
Vol. 6, pp. 878 (1936) has not made much progress to the present. This catalyst system has the serious drawback of producing large amounts of hexavalent chromium ions during manufacture. In order to prevent environmental pollution, these heavy metals are collected by an appropriate method, but the final treatment method of the heavy metal sludge generated here has not been established yet.

In order to solve this problem, Cu / Fe / Al oxide-based catalysts produced by various methods are disclosed in Japanese Patent Laid-Open No. 53-
92395, JP-A-55-8820, and JP-B-58-50.
775 etc. However, although these catalysts are superior to the conventional copper-chromite catalysts in terms of activity, selectivity and durability, they are disclosed in JP-A-53-92395 or JP-A-55.
As shown in -8820, the filtration rate at the time of filtering the catalyst from the catalyst-precipitated slurry during the catalyst production is slow, and there is a drawback that a large-scale filtration facility is required.
As disclosed in US Pat. No. 5,075,775, the catalyst is finely divided to make filtration difficult, and since urea is used as a catalyst precipitant, a large load is applied to the treatment of urea wastewater and ammonia wastewater. There was a problem with the manufacturing process.

Further, a method for improving the catalyst and a method for improving the production thereof are disclosed in JP-A-5-96169 and JP-A-5-168928. The catalyst has a carrier on which a metal oxide of Cu / Fe / Zn / Al is supported, but the catalyst manufacturing process is long and complicated, which is disadvantageous as a method for manufacturing an industrial catalyst. Thus, it is desired to develop an improved catalyst that can solve the problems of the conventional catalyst such as the copper-chromite catalyst.

[0006]

Therefore, the present invention does not have such problems, has high performance, high particle strength, good filterability, and high performance dehydration which can be produced by a simplified and reproducible method. An object is to provide a method for producing a carbonyl compound using an elementary catalyst.

[0007]

[Problems to be Solved by the Invention] The above-mentioned problem is "to develop a ternary alloy containing copper, aluminum and iron as a catalyst when producing a carbonyl compound by dehydrogenating a primary alcohol or a secondary alcohol. A method for producing a carbonyl compound, characterized by using the modified Raney copper catalyst obtained in the above. Hereinafter, the present invention will be described in more detail.

The present inventor has found that the problem of copper pollution
Establishing a method for producing a pollution-free catalyst as an alternative to a chromatographic catalyst, and a problem of suppressing fine particle formation of the catalyst, a simplified and economically advantageous method for producing the catalyst, and dehydrogenation of primary alcohol or secondary alcohol As a result of intensive research aimed at developing a catalyst showing high reaction performance, Cu / Al /
By using a modified Raney copper catalyst obtained by expanding an alloy made of Fe, it is possible to suppress the catalyst from becoming fine particles, improve the activity, selectivity, durability and filterability, and simplify the catalyst production process. The present invention has been completed and the present invention has been completed. That is, the present invention provides a modified Raney copper catalyst obtained by developing a ternary alloy containing Cu / Al / Fe as a catalyst when producing a carbonyl compound by dehydrogenating a primary alcohol or a secondary alcohol. A method for producing a carbonyl compound, which is characterized by being used.

The Raney copper catalyst used in the present invention is defined as follows based on known documents. That is, it is defined as a metal catalyst obtained by producing an alloy of a metal soluble in an alkali or an acid such as Al and Si and a metal insoluble in an alkali or an acid, and then developing this alloy. The metal composition of the metal catalyst obtained after the development is mainly Cu. Among the Raney copper catalysts, Al is often used as a metal soluble in alkali or acid in consideration of easiness of development and economy.

Usually, the main component of the Raney copper catalyst in which a Cu / Al alloy is expanded is Cu and Al remains, but the catalyst containing a component other than Al, Fe in the present invention, is a modified Raney copper catalyst (hereinafter referred to as modified R-Cu catalyst). Modified R-Cu catalyst used in the present invention (Cu / Al
/ Fe system) is 1 to 10 wt% Fe, 40 to 55 wt%
After forming a modified Raney copper alloy (hereinafter abbreviated as modified R-Cu alloy) in which Al and the balance are almost all Cu,
What was developed using an ordinary aqueous solution of an alkali metal hydroxide can be preferably used.

The alkali metal hydroxide used for development is sodium hydroxide (NaOH) or potassium hydroxide (KO).
H) is preferred, and its aqueous solution concentration is selected in the range of 10 to 40% by weight. It is preferable to add an amount of the alkali metal hydroxide solution in excess of the amount required to elute all the Al in the alloy. The development temperature is preferably selected in the range of 50 to 80 ° C., preferably 60 to 75 ° C. under atmospheric pressure. In the modified R-Cu catalyst of the present invention, the main catalytic active ingredient is C.
It is u and Fe, and Al is presumed to play a cocatalyst role. The dehydrogenation performance of the catalyst is significantly affected by its composition, but the preferred composition of Cu / Al / Fe is that Al is 0.02 to 0.20 in atomic ratio to Cu, Fe
Is in the range of 0.01 to 0.35. When Al is less than the lower limit value, the catalyst strength is reduced, and when it is more than the upper limit value, the catalyst specific surface area is reduced, which is practically disadvantageous.

When Fe is less than the lower limit value, the dehydrogenation activity is hardly improved, and when it exceeds the upper limit value, on the contrary, the activity is lowered, which is disadvantageous. The dehydrogenation activity of the Cu / Al system is extremely low, and it is considered that the activity is improved by the synergistic effect of Cu and Fe in the Cu / Al / Fe system, and it is presumed that the synergistic effect is remarkably exhibited in this range. As a catalyst for dehydrogenation reaction of primary alcohol or secondary alcohol,
The fact that the combination of Cu / Al / Fe is effective is disclosed in JP-A-5-168928. However, in the present invention, all the components effective as a catalyst are in the state of a metal oxide, and even considering the method for producing the catalyst and the post-treatment method,
It cannot be predicted that each component is in the metallic state.

In the catalyst of the present invention, Cu / Al / Fe, the raw material for producing the catalyst itself is already a metal, and the method for producing the catalyst is such that it is developed using an aqueous alkali metal hydroxide solution after forming an alloy. It is considered that the components are in a metallic state, and the state of the catalytically effective component is basically different from that of the preceding catalyst. Further, the catalyst of the present invention, Cu / Al /
Since the state of the catalytically active component in Fe is metallic, when used in the dehydrogenation reaction, the adsorptivity of alcohols on the catalyst surface is increased and the desorption of hydrogen generated in the reaction is promoted, which leads to dehydration. It is presumed that the efficiency of elementary reaction will increase and it will become an effective catalyst.

In general, the modified R-Cu catalyst is produced by producing a modified R-Cu alloy ingot, crushing the ingot to obtain an appropriate particle size distribution, and then expanding the ingot. In this case, the shape of the catalyst is irregular, but the catalyst strength is sufficient, so that it can be used as a practical catalyst. When the dehydrogenation reaction is carried out by the liquid phase suspension method, the irregular shape of the catalyst has a disadvantage in practical use. In this case, it is more practically advantageous to use a catalyst developed using a spherical modified R-Cu alloy.

A spherical modified R-Cu alloy, for example, 10-
When developed in the 200 μm particle size range, the particles hardly become fine particles by the operation, and the catalyst maintains the particle size range and maintains sufficient mechanical strength. As a method for producing the spherical modified R-Cu alloy, various known methods such as a gas atomizing method, a water atomizing method, and a rotating disk centrifugal atomizing method can be adopted. Also, JP-A-5-235
The method disclosed in 97 (Method for producing spherical Raney alloy for catalyst) can also be adopted.

After development, the modified R-Cu catalyst is usually stored in a water-sealed state. In use, it can be used after being drained and then dried in an inert gas. Since the catalyst is in a reduced state, it can be used without reduction, but it is preferably reduced with hydrogen or the like in the range of 100 to 300 ° C. immediately before use.

The process for producing the modified R-Cu catalyst of the present invention mainly comprises three steps of alloy production-development-water washing, and the process is simplified as compared with the prior catalyst production process.
It is an excellent method for producing industrial catalysts with good reproducibility. The characteristic of the modified R-Cu catalyst used in the present invention is that when a spherical catalyst is used in a liquid phase, it has good flow characteristics, sufficient particle strength, excellent sedimentation and filterability, and good workability. After that, since the catalyst is in a reducing state, it is necessary or easy to carry out preliminary reduction prior to the reaction. Compared with the preceding catalyst, the production process is simplified, which is economically advantageous.

In the method of the present invention, a carbonyl compound such as an aldehyde or a ketone can be produced by dehydrogenating a primary alcohol or a secondary alcohol in the presence of the above-mentioned catalyst for dehydrogenation reaction. it can. The primary alcohol used in the dehydrogenation reaction of the present invention has 3 or more carbon atoms, for example, propyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, decyl alcohol, lauryl alcohol, stearyl alcohol, oleyl alcohol. , Isostearyl alcohol, 2-ethylhexyl alcohol, 2-methyllauryl alcohol, geraniol, citronellol or allyl alcohol, crotyl alcohol, 2-buten-1-ol, 1
Aliphatic primary saturated or unsaturated alcohols such as 0-undecen-1-ol,

Or cyclohexyl carbinol, benzyl alcohol, anise alcohol, cumin alcohol,
Examples thereof include alicyclic or aromatic primary saturated or unsaturated alcohols such as phenylacetoalcohol, furfuryl alcohol, and cinnamyl alcohol. When dehydrogenating these primary alcohols, the corresponding aldehyde compound is can get.

Further, as the secondary alcohol used in the dehydrogenation reaction of the present invention, for example, isopropyl alcohol having a carbon number of 3 or more, secondary butyl alcohol,
3-methyl-2-butanol, 2-pentanol, 2-
Hexanol, 3-hexanol, 3-methyl-2-pentanol, 4-methyl-2-pentanol, 2-methyl-3-pentanol, 2-heptanol, 3-heptanol, 4-heptanol, 1,2-butane Diol,
Also, aliphatic secondary saturated or unsaturated alcohols such as 3-buten-2-ol, 1-hexen-3-ol, 4-ethyl-1-octen-3-ol,

Or cyclohexanol, P-menthane-
Alicyclic or aromatic such as 3-ol, 2-cyclopentenol, 2-cyclohexenol, 3-cyclohexenol, 1-phenylethanol, benzhydrol, 1-phenol-1-propanol, methylphenolcarbinol Examples thereof include secondary saturated or unsaturated alcohols of the group, and when these secondary alcohols are dehydrogenated, the corresponding ketone compounds are obtained.

Among these aliphatic alcohols, alicyclic alcohols or aromatic alcohols, alcohols preferably used in the method of the present invention are aliphatic saturated secondary alcohols such as isopropyl alcohol, secondary butyl alcohol and 4-methyl alcohol. 2-pentanol, carbon atoms C ₆ -C ₁₈
Aliphatic saturated primary or secondary alcohols and cyclohexanol, methylphenylcarbinol, benzyl alcohol within the range of

A method for synthesizing a corresponding carbonyl compound by dehydrogenating a primary alcohol or a secondary alcohol using the method of the present invention is as follows. When carrying out the dehydrogenation reaction of the primary or secondary alcohol by the method of the present invention, either a liquid phase method or a gas phase method can be used, but the performance of the modified R-Cu catalyst used, especially Considering the catalyst life, the high-temperature gas phase dehydrogenation method tends to shorten the catalyst life, which requires frequent regeneration and activation of the catalyst, which is a practical disadvantage compared to the liquid phase method. When carrying out the dehydrogenation reaction by the liquid phase method, the catalyst is used in the form of fine particles in a suspension bed or in a granular form in a fixed bed, and a flow type or a batch type reaction type is adopted. In the case of carrying out on a commercial scale, a method of suspending the modified R-Cu catalyst in a reactor of a flow type stirred tank type and continuously reacting is often used.

The primary or secondary alcohol in the reaction solution may be diluted with a suitable inert solvent before use.
Considering the separation / purification and productivity of the carbonyl compound, it is more advantageous to use it without diluting with a solvent. When a solvent is used, hydrocarbons having a boiling point of 200 ° C. or higher, such as paraffinic and naphthenic saturated hydrocarbons or a mixture thereof, can be preferably used.

The preferable reaction temperature is in the range of 100 to 350 ° C., but the range of 150 to 300 ° C. is particularly preferable in view of side reaction or polymerization prevention and productivity. The preferable reaction time is related to the reaction temperature, but is in the range of 0.5 to 10 hours, and particularly preferably in the range of 1 to 8 hours from the viewpoint of side reaction or polymerization inhibition. The reaction can be carried out under increased pressure, normal pressure or reduced pressure depending on the alcohol used, but when the boiling point of the primary or secondary alcohol used is over 200 ° C., it is particularly preferable to carry out the reaction under reduced pressure.

Although the dehydrogenation reaction will proceed even if the amount of the catalyst added is extremely small, the preferred concentration is 0.1 to 20% by weight, more preferably 0, relative to the primary or secondary alcohol used. It is in the range of 0.5 to 10% by weight. Modified R-C
It is preferred that the u-catalyst avoid contact with oxygen gas and oxygen-containing gas before and during use. Since the catalyst is oxidized, heat generation occurs, pre-reduction of the catalyst takes a long time, and an induction period is generated in the catalytic activity of dehydrogenation. The present invention will be described in more detail with reference to examples.

[0027]

【Example】

Example 1 The composition is Cu 43.3, Fe 3.8, Al 52.9% by weight.
6 using a 20 wt% NaOH aqueous solution using a spherical modified R-Cu alloy (particle size is 100 mesh or less)
After development in a temperature range of 0 to 65 ° C and washing with water, a spherical modified R-Cu catalyst was obtained. The catalyst is stored in a water-sealed state. The composition of the spherical modified R-Cu catalyst is Cu 89.9, Fe
8.10, Al 2.0% by weight, C of Fe and Al
The atomic ratio to u was 0.103 and 0.054, respectively. The particle size distribution of the catalyst was measured by a laser diffraction method, 2
0μ or less 8.0, 20-40μ 51.4, 40-80μ
The composition ratio was 36.9, 80 to 100 μ3.7%.

The fine particles of the catalyst that accompany the development of the alloy are negligible, and there is almost no difference in the particle size distribution between the alloy and the catalyst. The modified R-Cu catalyst was drained into a 250 ml flask connected to a condenser and a condenser for separating a reaction product, and then dried in vacuum at 100 ° C. 7.5 g and n-
After charging 100 g of octyl alcohol in a N ₂ atmosphere, N ₂ gas was blown in while stirring to raise the temperature to 190
The reaction was carried out for 5 hours at −197 ° C. under N ₂ gas flow of 10 L / hr to obtain n-octyl aldehyde. The alcohol and aldehyde in the distillate and the residual liquid were analyzed by gas chromatography to calculate the reaction results. The conversion of octyl alcohol was 57.2% and the selectivity of octyl aldehyde was 70.5%.

Example 2 The composition was Cu41.6, Fe7.6, Al50.8% by weight.
A spherical modified R-Cu alloy was developed in the same manner as in Example 1 and washed with water to obtain a spherical modified R-Cu catalyst. The composition of the spherical modified R-Cu catalyst is Cu81.7, Fe15.5, A
12.8% by weight, and atomic ratios of Fe and Al to Cu were 0.216 and 0.081, respectively. After draining, the dehydrogenation reaction of n-octyl alcohol was carried out under the same test conditions as in Example 1 except that 7.5 g of a catalyst dried in vacuum at 100 ° C. was used. Octyl alcohol conversion 5
It was 4.2% and the selectivity of octyl aldehyde was 70.6%.

Comparative Example 1 A spherical modified R-Cu alloy having a composition of Cu 50.0 and Al 50.0 wt% was developed in the same manner as in Example 1 and washed with water,
A spherical R-Cu catalyst was obtained. The composition of the spherical R-Cu catalyst is C
u was 98.7 and Al was 1.3% by weight. After draining 1
The dehydrogenation reaction of n-octyl alcohol was carried out under the same test conditions as in Example 1 except that 7.5 g of the catalyst dried in vacuum at 00 ° C. was used. The conversion of octyl alcohol was 10% or less.

Example 3 Using the same catalyst as used in Example 1, the test conditions were the same and the changes in activity and particle size distribution due to repeated use of the catalyst were measured. That is, the operation of dehydrogenating octyl alcohol using 7.5 g of the dried catalyst and using the separated and recovered catalyst for the reaction again was repeated 3 times.
The conversion of octyl alcohol was 55 to 58%, the selectivity of octyl aldehyde was 70 to 72%, and no change was observed in the catalyst particle size distribution.

Example 4 100 g of n-lauryl alcohol as a raw material alcohol
Was used, and the dehydrogenation reaction of lauryl alcohol was performed under the same test conditions as in Example 1 except that the pressure inside the reaction system was reduced to 100 mmHg. Conversion rate of lauryl alcohol 53.5%, selectivity of lauryl aldehyde 6
It was 6.0%.

Example 5 The dehydrogenation reaction was performed in the same manner as in Example 1 except that dibenzyl alcohol was used as the raw material alcohol. The conversion of benzyl alcohol was 25.0% and the selectivity of benzaldehyde was 95.0%.

Example 6 The dehydrogenation reaction was carried out in the same manner as in Example 1 except that secondary butanol was used as the raw material alcohol and the reaction temperature was 95 to 105 ° C. Secondary butanol conversion 12.0%,
The methyl ethyl ketone selectivity was 97.5%.

[0035]

INDUSTRIAL APPLICABILITY By using the modified R-Cu catalyst as a catalyst for dehydrogenation in the method of the present invention, a corresponding carbonyl compound can be efficiently produced from a primary alcohol or a secondary alcohol, which is industrially useful. is there.

Claims (2)

[Claims] 1. A modified Raney copper catalyst obtained by developing a ternary alloy containing copper, aluminum and iron as a catalyst when producing a carbonyl compound by dehydrogenating a primary alcohol or a secondary alcohol. A method for producing a carbonyl compound, which comprises using 2. The composition of aluminum and iron in the modified Raney copper catalyst is such that the atomic ratio of copper to aluminum is 0.02 to 0.02.
Process according to claim 1, characterized in that a catalyst in the range 0.20, iron 0.01 to 0.35 is used.