JPH11147845A - Production of aldehydes and/or alcohols - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce aldehydes and/or alcohols in a high yield by the vapor- phase reduction of a carboxylic acid. SOLUTION: A carboxylic acid or its derivative is reduced with molecular hydrogen in vapor phase in the presence of a catalyst produced by supporting a ruthenium component, a tin component and a platinum component on a carrier. The catalyst carrier is silica and the carboxylic acid or its derivative is selected from alicyclic carboxylic acids, aromatic carboxylic acids, heterocyclic carboxylic acids and their derivatives.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to aldehydes and / or aldehydes.
Alternatively, the present invention relates to a method for producing alcohols. More specifically, the present invention relates to a method for producing aldehydes and / or alcohols with high yield using a highly active catalyst when carboxylic acid or its derivative is reduced in the gas phase with molecular hydrogen.

[0002]

2. Description of the Related Art Alcohols and aldehydes are compounds useful as intermediates in organic synthesis. Aldehydes,
Alternatively, various production methods for alcohols are known, and one of them is a method for directly producing aldehyde and / or alcohol from carboxylic acid using molecular hydrogen. This method is considered the most desirable method, but has been considered technically difficult. Reactions for the direct hydrogenation of carboxylic acids with molecular hydrogen to produce alcohols are known. These require a high pressure for the reaction, and the reaction is mainly performed in a liquid phase. Therefore, a reaction device for a high-pressure reaction is required, and there are problems in terms of cost and safety, and in addition, since the reaction is a liquid phase reaction, elution of a catalyst component occurs, thereby shortening the life of the catalyst. For example, JP-A-7-165644 discloses a method for producing 1,4-butanediol and tetrahydrofuran by hydrogenating a C ₄ carboxylic acid such as maleic acid in a liquid phase in the presence of a supported ruthenium-platinum-tin catalyst. Is disclosed. This method also requires a high pressure for the reaction, and the reaction is mainly performed in a liquid phase. No aldehyde formation has been reported by this method. In the gas phase reaction, and directly hydrogenating carboxylic acids at around normal pressure, if a catalyst capable of obtaining an alcohol can be obtained, the above problems can be avoided and the process is advantageous. There are few reports of catalysts.

[0003] On the other hand, when aldehydes are produced by directly hydrogenating carboxylic acids, a method in which a metal oxide is used as a catalyst to carry out a reaction in a gas phase has been generally proposed. Among these various metal oxides, it has been reported that a high aldehyde selectivity can be achieved when a catalyst containing zirconium oxide as a main component is used. (JP-A-60-152434, JP-A-60-152)
243037, JP-A-61-115043).
However, when these various metal oxides were used as catalysts, the reaction temperature was as high as about 350 ° C. Therefore, when the starting carboxylic acid or its derivative is thermally unstable, it has been difficult to carry out the reaction. Further, when the products are thermally unstable, they are decomposed due to heat, and the selectivity of the target aldehyde is greatly reduced, which is not a preferable method. For example, Japanese Patent Publication No. 7-68155 discloses a method of hydrogenating a carboxylic acid in the gas phase using a catalyst in which ruthenium and tin are supported on a carrier such as silica or alumina. In this case, it is reported that the gas phase reaction proceeds at a low temperature of around 250 ° C. under normal pressure, but the activity itself is low and the selectivity of aldehyde is insufficient, so that the secondary reaction by It is not practical for practical use due to the large amount of product produced. In addition, in these aldehyde production methods in the gas phase, alcohol may be slightly obtained as a by-product, but the yield is low and coproduction of aldehyde and alcohol cannot be expected.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above background, and it is an object of the present invention to directly hydrogenate carboxylic acids in a gas phase reaction and at a low pressure near normal pressure to produce an aldehyde and / or It is an object of the present invention to provide a method for producing alcohol.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, by using a catalyst in which three components of ruthenium, tin and platinum are supported on a carrier, this object has been achieved. Achieved. That is, the gist of the present invention is that aldehydes and / or alcohols characterized in that they are reduced in the gas phase by molecular hydrogen in the presence of a catalyst comprising a ruthenium component, a tin component, and a platinum component supported on a carrier. In the manufacturing method.

Hereinafter, the present invention will be described in detail. The starting material of the present invention is an aliphatic, alicyclic, aromatic or heterocyclic carboxylic acid or a derivative thereof. As the aliphatic carboxylic acid, specifically, acetic acid, propionic acid,
Butyric acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, hexanoic acid, heptanoic acid, octanoic acid, 2-ethylhexanoic acid, nonanoic acid, decanoic acid, undecanoic acid, rallic acid,
Tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, stearic acid, isostearic acid, nonadecanoic acid, tricosanoic acid, tetracosanoic acid, acrylic acid,
C2-C2 such as methacrylic acid, 10-undecenoic acid, 9-octadecenoic acid, oleic acid, and 11-eicosenoic acid
And 4 saturated or unsaturated carboxylic acids. Further, polycarboxylic acids such as oxalic acid, malonic acid, diethylmalonic acid, succinic acid, maleic acid, glutaric acid, adipic acid, decandioic acid and octadecandioic acid can also be used.

The alicyclic carboxylic acids include cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, 1,4-cyclohexanedicarboxylic acid and the like. Further, the aliphatic carboxylic acid or the alicyclic carboxylic acid may have a group which is inert to the reaction as a substituent. Examples of such a substituent include an aryl group, O, S, N and the like. A heterocyclic group, an ether group, an alkoxy group or the like containing the above atom. Specifically, phenylacetic acid, cinnamic acid, glycolic acid and the like are exemplified.

The aromatic carboxylic acid has the general formula Ar- (COO)
H) It can be represented by n (in the formula, n is 1 or 2, and Ar represents an aryl group which may have a substituent). The aryl group represented by Ar typically includes a phenyl group, a naphthyl group, and an anthryl group. Examples of the substituent that the aryl group may have include, for example, an alkyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, Examples include a halogen atom, a hydroxyl group, a formyl group, and an acyl group. Specific compounds include, for example, benzoic acid, toluic acid, dimethylbenzoic acid, cyclohexylbenzoic acid, cumic acid, t-butylbenzoic acid, phenylbenzoic acid, anisic acid, phenoxybenzoic acid, chlorobenzoic acid, fluorobenzoic acid , Hydroxybenzoic acid,
Carboxylic acids such as acetylbenzoic acid, naphthoic acid, naphthalenedicarboxylic acids, anthracenecarboxylic acid and the like can be mentioned. Also, phthalic acid and the like can be used.

The heterocyclic ring constituting the starting heterocyclic carboxylic acid used in the present invention has at least one heterocyclic ring in the ring.
N, S, or O atoms, specifically, a pyrrole ring, a furan ring, a thiophene ring, an oxazole ring, a thiazole ring, an oxazoline ring, an imidazole ring, an imidazoline ring, a pyrazole ring, a pyran ring, Examples thereof include a thiopyran ring, a pyridine ring, a quinoline ring, an oxazine ring, a thiazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an azepine ring, and an oxzepine ring. In particular,
Nicotinic acid, furan carboxylic acid, thiazole carboxylic acid and the like can be mentioned. Further, the heterocyclic carboxylic acid may have, as a substituent, a group which is inert to the reaction. Examples of such a substituent include an aryl group, a heteroatom containing an atom such as O, S, and N. Examples include a ring group, an ether group, and an alkoxy group.

As the raw material used in the present invention, the above-mentioned carboxylic acid derivatives can also be used. Such derivatives include:
For example, esters, acid anhydrides and the like can be mentioned. The ester may be any of aliphatic, alicyclic, and aromatic esters, and specifically, methyl ester, ethyl ester, n-butyl ester of the carboxylic acid exemplified above,
There are isobutyl ester, octyl ester, cyclohexyl ester, phenyl ester and the like. In the case of polycarboxylic acid, it may be a half ester or an ester with two kinds of alcohols. The anhydride may be a homo anhydride or a hetero anhydride. As the derivative of the aromatic carboxylic acid or the heterocyclic carboxylic acid, a lower alkyl ester is preferable. Among the above-mentioned carboxylic acids and derivatives thereof, it is preferable to use an alicyclic carboxylic acid, an aromatic carboxylic acid, a heterocyclic carboxylic acid or a derivative thereof as a starting material for the method of the present invention. Or their derivatives are preferred.

In the method of the present invention, ruthenium (R
u) and platinum (Pt) (hereinafter Ru and Pt are collectively referred to as
It is referred to as "noble metal component". ) And tin (Sn) supported on a carrier. As the carrier, a porous carrier such as activated carbon, graphite, diatomaceous earth, silica, alumina, titania, zirconia, and chromia can be used alone or in combination of two or more. Preferably, silica, activated carbon, or chromia is used, and more preferably, silica is used. The method for preparing the catalyst is not particularly limited, and for example, can be prepared by a known method such as a coprecipitation method or a dipping method. When the immersion method is used, for example, a solvent capable of dissolving the compound of the noble metal component and the tin compound, for example, dissolved in water to form a solution, and a separately prepared porous carrier is immersed in this solution, and the noble metal component is immersed in the carrier. And a catalyst component comprising tin. The method for supporting each catalyst component on the carrier is not particularly limited, either, all the metal components are supported simultaneously at a time, each component is supported individually one by one, or some of the components are supported. May be combined and carried multiple times.

A noble metal component (total amount of Ru and Pt);
The supported amount of tin is usually 0.5 to 50% by weight, preferably 1 to 20% by weight, based on the carrier in terms of metal element. Pt is preferably present in an amount of 0.01 to 10 times the weight of Ru from the viewpoint of improving the activity. Tin is
It is usually preferable to coexist 0.1 to 20 times by weight of the noble metal component from the viewpoint of improving the selectivity of the product. As a noble metal component and a raw material compound of tin used in the present invention, mineral salts of such metals such as nitric acid, sulfuric acid and hydrochloric acid are generally used, but organic acid salts such as acetic acid and hydroxides thereof are used. , Oxides or complex salts can also be used. As these raw material compounds, those which are soluble in a solvent used when immersed and supported on a carrier, for example, water or the like, are preferable in terms of operation.

Specifically, the ruthenium compound as a catalyst raw material includes, for example, ruthenium nitrate, ruthenium sulfate, ruthenium chloride, ruthenium bromide, ruthenium iodide, ruthenium hydroxide, ruthenium oxide, potassium ruthenate, ruthenium alkoxide, Ammonium oxydecachlorodiruthenate, ammonium pentachloroaquaruthenate, ammonium ruthenate, potassium oxydecachlorodiruthenate, potassium pentachloroaquaruthenate, potassium perruthenate, nitrosylruthenium nitrate, oxydecachlorodiruthenate Sodium, hexaammineruthenium chloride, pentaamminechlororuthenium chloride, hexaammineruthenium bromide, dodecacarbonyltriruthenium, hexa Rubo sulfonyl tetrachloro diruthenium, tricarbonyl trichloro ruthenium cesium,
Tris (acetylacetonato) ruthenium, tricarbonylbis (triphenylphosphine) ruthenium, dichlorotris (triphenylphosphine) ruthenium, and the like.

Specific examples of the platinum compound as a catalyst raw material include platinum sulfate, platinum chloride, platinum bromide, platinum iodide, platinum oxide, ammonium hexabromoplatinate, ammonium tetrachloroplatinate, and dinitrodiamine platinum. , Dinitrosulfite platinate, hexabromoplatinate, hexachloroplatinate, hexahydroxyplatinate,
Potassium hexabromoplatinate, potassium hexachloroplatinate, potassium hexaiodoplatinate, potassium hexahydroxoplatinate, potassium tetrabromoplatinate, potassium tetrachloroplatinate, sodium hexabromoplatinate, sodium hexachloroplatinate, sodium hexahydroxoplatinate, tetrachloroplatinum Examples include sodium platinate, tetraammineplatinum chloride, tetraammineplatinum hydroxide, and tetracyanoplatinic acid. Specific examples of the tin compound as a catalyst raw material include tin sulfate, tin phosphate, tin chloride, tin bromide, tin iodide, tin oxide, potassium stannate, sodium stannate, tin acetate, and tin alkoxide. , Acetylacetonate complex of tin and the like. The tin compound is stannous (II)
Any of a compound and a stannic (IV) compound may be used.

After the solution of the catalyst component is immersed and supported on the porous carrier (when the immersion supporting process is performed a plurality of times, each time), drying may be performed if necessary. Although there is no limitation on the drying method, for example, drying under reduced pressure, drying by air drying, heating drying in a muffle furnace, drying under a temperature condition of 100 ° C. to 150 ° C. under an inert gas stream, etc. Method. Specifically, for example, drying is performed under reduced pressure under a temperature condition of 50 to 100 ° C., and then under a stream of an inert gas such as argon gas.
It is carried out by a method of treating under a temperature condition of 0 to 150 ° C. Thereafter, if necessary, firing and reduction treatments are performed.
When performing a baking process, it is usually performed in a temperature range of 100 ° C to 600 ° C, preferably in a range of 200 ° C to 400 ° C.

Further, it is desirable that the catalyst is activated by performing a reduction treatment. When performing the reduction treatment, a known liquid-phase reduction method and a known gas-phase reduction method are employed. In the case of the gas phase reduction method, the reaction is usually performed at a temperature in the range of 100 ° C to 600 ° C, preferably in the range of 300 ° C to 500 ° C. Examples of the liquid phase reduction method include a formalin reduction method, a hydrazine reduction method, and a lithium aluminum hydride reduction method. Care must be taken when the temperature of the reduction treatment is too low or the treatment time is too short because the catalyst may not be sufficiently activated and the expected effect may not be sufficiently exerted. Although the details of the structure of the catalyst after the reduction treatment are unknown, it is estimated that substantially all of the noble metal components are reduced to the metal under the reducing conditions under which the catalyst is sufficiently activated. Have been.

The reduction reaction of the carboxylic acid according to the present invention is carried out in the gas phase using the thus obtained catalyst and using molecular hydrogen. By using the catalyst according to the present invention, using a pressure near normal pressure without using high pressure conditions,
In addition, the carboxylic acid hydrogenation occurs with high activity at a lower temperature than in the past, and aldehydes and / or alcohols can be produced in high yield. Further, the method of the present invention has an advantage that both alcohol and aldehyde can be produced simultaneously. The production ratio of aldehyde and alcohol varies depending on the raw materials and reaction conditions.

The produced alcohol partially reacts with a carboxylic acid or a carboxylic acid produced from a carboxylic acid derivative as a raw material to form a carboxylic acid ester.
By returning this carboxylic acid ester into the reaction system, alcohol and / or aldehyde can be formed again. Therefore, in this specification, the carboxylic acid ester formed by the reaction is also used as an active ingredient (product). Is considered. From polycarboxylic acids or derivatives thereof,
Polyaldehyde, hydroxyaldehyde, polyol,
Aldehydic carboxylic acids or their esters, hydroxycarboxylic acids or their esters, lactones and the like are produced, but the ratio varies depending on the raw materials and reaction conditions.

In the reduction reaction with molecular hydrogen of the present invention, the reaction pressure may be carried out at around normal pressure, but may be in a pressurized state. It can be carried out between normal pressure and 100 kg / cm ² . Preferably, it is carried out at 1 to 50 kg / cm ² . Further, the reaction temperature is 100 ° C to 500 ° C, preferably 150 ° C to 400 ° C, more preferably 200 ° C to
Temperatures between 300 ° C. are selected.

As a reaction method in the hydrogenation reaction of the present invention, it is preferable to carry out the reaction under a hydrogen stream using the above-mentioned catalyst as a fixed bed catalyst. In this case, the concentration of the carboxylic acid or its derivative in the feedstock is In the gas phase, the content is preferably 20 (volume)% or less, preferably 0.01 to 10 (volume)%. If the concentration is too low, the efficiency of the reaction will be poor. On the other hand, if the concentration is too high, a higher reaction temperature will be required to promote the reaction, not only the selectivity will be poor, but also the catalyst life will be shortened. May occur. Note that the hydrogen used may contain a gas that does not adversely affect the reaction, such as nitrogen or water vapor. The alcohols and / or aldehydes generated by the reaction are separated and purified into their components by a known method such as distillation, or
The mixture can be supplied to subsequent steps as it is.

[0021]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples unless it exceeds the gist of the present invention. In the following examples, “%” means “% by weight”.

[Catalyst Preparation Example] (0.4% Ru / 2.9% Sn / 0.4% Pt / SiO)
Preparation of ₂ ) RuCl _3.
3H ₂ O to 0.133 g, the SnCl ₂ · 2H ₂ O 0.
_{689g, H 2 PtCl 6 · 6H} 2 O was 0.1g weighed, further dissolved by adding 13ml of 5N-HCl aqueous solution, SiO ₂ (trade name as a carrier: CARIACT Q-1
(0, 10 to 20 mesh) was added and shaken well. Then, at 50 ° C, 25 mmHg in a rotary vacuum dryer.
After removing water as a solvent under the above conditions, the mixture was calcined at 150 ° C. for 1 hour in a nitrogen atmosphere. Then, under hydrogen flow, 300
The mixture was treated at 30 ° C. for 30 minutes to obtain a catalyst. The resulting catalyst is
0.4% ruthenium, 2.9% tin,
Contains 0.4% of platinum.

[Comparative Example 1 for Preparation of Catalyst] (Preparation of 0.4% Ru / 2.9% Sn / SiO ₂ ) RuCl ₃ .3H ₂ O was added to a flask having a capacity of 100 ml in a flask of 0.1 ml.
After weighing 133 g and 0.689 g of SnCl ₂ .2H ₂ O, 13 ml of a 5N-HCl aqueous solution was added and dissolved, and then SiO ₂ (trade name: Carract Q-1) was used as a carrier.
(0, 10 to 20 mesh) was added and shaken well. Then, at 50 ° C, 25 mmHg in a rotary vacuum dryer.
After removing water as a solvent under the above conditions, the mixture was calcined at 150 ° C. for 1 hour in a nitrogen atmosphere. Then, under hydrogen flow, 300
The mixture was treated at 30 ° C. for 30 minutes to obtain a catalyst. The resulting catalyst is
The carrier contains 0.4% of ruthenium and 2.9% of tin.

Example 1 (Hydrogenation reaction of benzoic acid with Ru / Sn / Pt / SiO ₂ ) 7.4 ml of the catalyst produced based on the catalyst preparation example was charged into a tubular reactor, and the reaction was carried out at normal pressure and at a reaction temperature of 230. ° C, space velocity of benzoic acid: LHSV = 0.054 kg / l-ca
t. Hr, space velocity of hydrogen: GHSV = 1250 hr
^Under the conditions of ^-1 , the hydrogenation reaction of benzoic acid was performed in the gas phase. Benzoic acid conversion was 54.7%, benzaldehyde selectivity was 36.2%, and benzyl alcohol selectivity was 53.9%.
Met. The formation rate of benzaldehyde and benzyl alcohol is 0.435 mol / kg-cat. Hr.

Comparative Example 1 (Hydrogenation reaction of benzoic acid with Ru / Sn / SiO ₂ )
Catalyst Preparation 7.4 ml of the catalyst produced based on Comparative Example 1 was charged into a tubular reactor, and at a normal pressure and a reaction temperature of 230 ° C., a space velocity of benzoic acid: LHSV = 0.054 kg / l-ca
t. Hr, space velocity of hydrogen: GHSV = 1250 hr
Hydrogenation of benzoic acid was performed in the gas phase under the condition of ^-1 . Benzoic acid conversion 8.4%, benzaldehyde selectivity 80.
9% and benzyl alcohol selectivity was 14.7%.
The production rate of benzaldehyde and benzyl alcohol is 0.12 mol / kg-cat. Hr.

[0026]

As shown in the examples, the method of the present invention comprises:
By using Ru / Sn / Pt / support as the catalyst, the production rate and the conversion are remarkably improved as compared with the case where a conventional catalyst comprising Ru / Sn / support is used. Also,
Alcohol, which has been difficult in the conventional gas phase method, can be obtained in good yield.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C07C 47/54 C07C 47/54 // C07B 61/00 300 C07B 61/00 300

Claims (3)

[Claims] An aldehyde which is characterized in that a carboxylic acid or a derivative thereof is reduced in the gas phase with molecular hydrogen in the presence of a catalyst comprising a ruthenium component, a tin component, and a platinum component supported on a carrier. Or method for producing alcohols 2. The method for producing aldehydes and / or alcohols according to claim 1, wherein the catalyst carrier is silica. 3. The carboxylic acid or its derivative is selected from alicyclic carboxylic acid, aromatic carboxylic acid, heterocyclic carboxylic acid and derivatives thereof.
Or the method for producing aldehydes and / or alcohols according to 2.