JPH03245843A - Preparation of catalyst for producing unsaturated diester - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for preparing a catalyst for producing an unsaturated diester, and more specifically, the present invention relates to a method for preparing a catalyst for producing an unsaturated diester, and more specifically, a gas phase flow reaction of a mixed gas containing a conjugated diene, an organic carboxylic acid, and oxygen. The present invention relates to a method for preparing a catalyst containing antimony, palladium, and vanadium as essential components, which is used to produce an unsaturated diester.

[Conventional technology]

Conventionally, antimony, palladium, and vanadium are essential components as they have a remarkable catalytic effect in the reaction to synthesize unsaturated diesters by conducting a gas phase flow reaction of a mixed gas containing a conjugated diene, an organic carboxylic acid, and molecular oxygen. Catalysts are known (Special Publication No. 53-15488)
Publication No.). In addition to the primary metal component, it is known to further contain an alkali metal carboxylate as a cocatalyst to obtain higher catalytic activity (same as above), or an alkali metal carboxylate and an alkali metal component. It is known to contain both metal halides (Japanese Patent Publication No. 154.90/1983).

Generally, in order to prepare a catalyst containing antimony, palladium, and vanadiram as components, an antimony source substance consisting of an antimony compound, a palladium source substance consisting of a palladium compound, and a vanadium source substance consisting of a vanadium compound are mixed in a suitable common solvent. After impregnating the carrier with this solution, the solvent is evaporated from the carrier to attach each of the metal source substances to the carrier, and then this is placed in a gas stream of hydrogen gas or an organic compound with reducing power, or A method is used in which antimony, palladium, and vanadium are precipitated and fixed as metals or oxides on a carrier by reduction treatment using a known reducing agent such as hydrazine or formalin. When a co-catalyst is also supported, a treatment is then carried out to support either an alkali metal carboxylate alone or both an alkali metal carboxylate and an alkali metal halide.

[Problem that the invention seeks to solve]

However, it is a well-known fact that the performance of a catalyst is greatly affected not only by the types and ratios of its constituent components, but also by the preparation method, processing conditions during the preparation process, and even differences in starting materials. It is.

This situation also applies to the catalyst system targeted by the present invention, and even if the ratios of palladium, antimony, and vanadium are the same, the actual yield may differ due to differences in specific preparation methods and treatment methods. The activity of the catalysts used will vary widely. In particular, in catalysts containing antimony as a component, this tendency is even more pronounced than in the case of other catalyst systems, and in fact, it is difficult to reproducibly prepare catalysts that exhibit high and stable activity. Finding a method must be said to be a problem of extremely important industrial importance.

The present invention has been made based on the above circumstances, and its object is to provide a catalyst for producing unsaturated diesters containing antimony, palladium and vanadium as essential components, which has high activity and stable activity. The object of the present invention is to provide a method by which a catalyst with excellent properties can be easily prepared.

[Means for solving problems]

The present inventors have repeatedly studied methods for preparing catalysts containing antimony as one of the components, as well as palladium and vanadium, and have found that the activity of the resulting catalyst is
Basically, we found that there is a close relationship between the method of supporting antimony and the method of supporting palladium, and based on this, we supported antimony as antimony oxide on a carrier, and then supported palladium using an organic solvent. The inventors have discovered that a catalyst with extremely high activity and excellent stability can be easily obtained by this method, and based on this knowledge, they have completed the method of the present invention.

The method for preparing a catalyst for producing an unsaturated diester of the present invention is directed to antimony, palladium, and vanadium, which are used in a gas phase flow reaction of a mixed gas containing a conjugated diene, an organic carboxylic acid, and oxygen to produce an unsaturated diester. In the method for preparing a catalyst having antimony oxide as an essential component, oxidation is carried out by means including a step of supporting a palladium source material by impregnating a catalyst material in which antimony oxide is supported on a carrier with a solution of the palladium source material in an organic solvent. The method is characterized in that a catalyst material on which antimony, a palladium source material, and a vanadium source material are supported is obtained, and this catalyst material is subjected to a reduction treatment.

The present invention will be explained in detail below.

In the present invention, basically, a catalyst material in which antimony oxide is supported on a carrier is impregnated with a solution obtained by dissolving a palladium source material in an organic solvent, so that a palladium source material is supported on the catalyst material. Catalysts for specific reactions characterized by antimony, palladium and vanadium are prepared by supporting a vanadium source material on the catalyst and subjecting the resulting catalyst material to a reduction treatment.

Preparation of catalyst material supporting antimony oxide> In the present invention, a catalyst material in which antimony oxide is supported on a carrier (
The method for preparing the "first catalyst material" is not particularly limited, and various methods can be used.

- For boat fishing, a carrier is impregnated with a solution obtained by uniformly dissolving an antimony compound in a suitable solvent, then the solvent is evaporated, and then the antimony compound is subjected to a reaction treatment such as neutralization or decomposition. There is a method in which the antimony compound is converted into antimony oxide, and a method in which a solution of antimony oxide is prepared and impregnated into a carrier, and then the solvent is evaporated.

(2) Specific Supporting Methods Examples of specific methods are listed below, but the methods for supporting antimony oxide used in the present invention are not limited to these.

(1) After supporting antimony chloride on a carrier, dechlorination is carried out by a method such as neutralizing antimony chloride with an alkali or reacting with water or alcohol to decompose it through antimony oxychloride (SbOCI7). , thereby obtaining a first catalyst material.

(2) After supporting antimony compounds on a carrier using an aqueous solution of potassium antimonyl tartrate, potassium pyroantimonate, etc., this is neutralized with nitric acid, etc., and after removing the alkali, a calcination treatment is performed. ,
A method for obtaining a first catalyst material.

(3) A method of obtaining the first catalyst material by adding tartaric acid or the like to antimony oxide and dissolving it in water, using this solution to support the antimony compound on a carrier, and then performing a calcination treatment to remove organic components. .

(4)) Dissolve alkoxyantimony such as rimethoxyantimony, triethoxyantimony, and tributoxyantimony in a solvent, use this solution to support the antimony compound on a carrier, and react with its condensate to form antimony oxide. A method of obtaining the first catalyst material by decomposing the catalyst into alcohol and removing the alcohol.

The first catalyst material on which antimony oxide is supported as described above can be subjected to a calcination treatment after its preparation. This baking treatment can remove residual moisture or organic components. This firing treatment is usually carried out at a temperature of 3f)Qt: or higher, preferably 400°C or higher, in an air atmosphere.

(2) Support The support used in the present invention is not particularly limited, and common catalyst supports used industrially, such as phosphoric acid, alumina, titania, zirconia, activated carbon, diatomaceous earth, and others can be used.

<Supporting Palladium> The first catalyst material is impregnated with a solution of the palladium source material in an organic solvent to support the palladium source material.

(2) Solvent As the solvent for dissolving the palladium source material, an organic solvent capable of dissolving the palladium source material is used, and its type is not particularly limited.

When water is used as a solvent, a sol in which water is coordinated with antimony oxide is likely to be produced, and as a result of this covering the palladium source material, the resulting catalyst tends to have low activity.

Here, as the organic solvent, methanol,
Alcohols such as propatool, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, esters such as methyl acetate, methyl acetate butinopeformate, T-butyrolactone, ethers such as diethyl etherepetetrahydrofuran, chlorides methylene, chloroform, dichloroethane,
halogenated hydrocarbons such as trichloroethane, nitro compounds such as nitrobenzene, dimethyl sulfoxide,
Examples include sulfoxides such as sulforane, N-methylpyrrolidone, and the like.

(2) Palladium source material The palladium source material used in the present invention is not particularly limited as long as it is other than a halogen-containing palladium source material. When a palladium source material containing a halogen is used, such as palladium chloride or potassium chloride palladate, antimony oxide changes to sublimable antimony halide, and the antimony evaporates and is lost during the preparation process. , which ultimately causes a decrease in catalyst activity.

Specific examples of palladium source substances include organic complexes such as palladium nitrate, palladium acetate, palladium sulfate, tetraammine palladium nitrate or acetate, palladium acetylacetonate, and the like, all of which are suitable for dissolving the compound. It can be suitably used in combination with a suitable solvent.

■ Supporting palladium source material Impregnating the first catalyst material already supported with antimony oxide with a solution in which the palladium source material is dissolved in an organic solvent;
The palladium source material is supported by evaporating the organic solvent and drying it. Thereafter, by performing a firing treatment, unnecessary organic components and the like can be removed. This firing treatment is usually carried out at 200°C or higher, preferably at 300°C.
The process is carried out in air or an inert gas atmosphere at a temperature above 100%. The time for this baking treatment is not particularly limited, but is preferably 0.5 hours or more, more preferably 1 hour or more.
It's more than an hour.

<Supporting Vanadium Source Material> In the present invention, a vanadium source material is supported on the carrier, but the method is not limited. That is,
A vanadium source material may be supported simultaneously when an antimony source material is supported, or a vanadium source material may be supported simultaneously when a palladium source material is supported. Alternatively, the vanadium source material can be supported alone in a step after supporting antimony oxide and before supporting the palladium source material, or in a step after supporting antimony oxide and the palladium source material.

In the case where a vanadium source material is supported on the first catalyst material that has already supported antimony oxide, it is not possible to use a vanadium source material that contains halogen, as in the case of palladium source material, but the vanadium source used The substance is not limited by anything other than this. As specific examples of vanadium source substances, for example,
Organic complexes such as ammonium metavanadate, vanadyl sulfide, vanadium oxide, vanadyl oxalate, and vanadium oxide acetylacetonate can be preferably used.

When a vanadium source material is supported simultaneously with an antimony source material, it is also possible to use a vanadium compound containing norogen, such as vanadium chloride or vanadium bromide, as the vanadium source material.

The solvent used when supporting the vanadium source material is not particularly limited, except that an aqueous hydrochloric acid solution cannot be used when supporting the vanadium source material on the first catalyst material. When supporting the vanadium source material alone, water may be used as the solvent.

Component Concentration in the Support The concentration of the palladium source material in the support can be varied within a wide range. Usually, it is preferably in the range of 0.1 to 10% by weight in terms of metal palladium based on the carrier. However, even at concentrations outside this range, the catalytic action is not lost.

In the final catalyst, the ratio of antimony and vanadium to palladium is usually 1
It is preferably in the range of 0.01 to 20 gram atoms, particularly preferably in the range of 0.1 to 10 Dalham atoms.

Further, the ratio of vanadium to antimony is not particularly limited, but it is preferable that the ratio of antimony to 1 gram atom of vanadium is within the range of 0.1 to 10 Durham atoms.

If the palladium source material and vanadium source material supported as described above exist in the form of undecomposed salts,
A calcination treatment can be performed before the subsequent reduction treatment.

This firing process is performed in an inert gas or air.
It is usually carried out at a temperature of 200°C or higher, preferably 300°C or higher.

Reduction treatment>
The catalyst material is subjected to a reduction treatment.

This reduction treatment can be carried out by gas phase treatment using a stream of reducing gas such as hydrogen gas, carbon oxide gas, or organic compounds with reducing power such as methyl alcohol or ethyl alcohol, or by a single vessel such as hydrazine or formalin. This can be carried out by liquid phase treatment using a substance used as a reducing agent or a solution thereof. In the case of liquid phase treatment, after the reduction treatment is completed, it is preferable to carry out a normal drying treatment in the atmosphere, for example.

Through this reduction treatment, antimony, palladium, and vanadium are precipitated on the carrier as metals or oxides, and therefore, the desired catalyst containing these components is obtained.

<Co-catalyst> The catalyst obtained as described above can further support a co-catalyst, and the catalyst obtained in this case has even higher activity. The cocatalyst component is an alkali metal carboxylate or a combination of an alkali metal carboxylate and an alkali metal halide; in the latter case, for example, a mixture of both compounds is used in the supporting treatment. Served.

Examples of alkali metal carboxylates include lithium, sodium, potassium, rubidium, and cesium, and alkali metal halides include fluoride such as lithium, sodium, potassium, rubidium, and cesium. compounds, chlorides, bromides,
Examples include iodides.

Two or more types of alkali metal carboxylates and alkali metal halides can also be used in combination.

The amount of these alkali metal carboxylates and alkali metal halides that should be supported on the carrier is not particularly limited, but the amount of each of them is 0.0% per 1 g of the carrier.
01 to 4 (preferably at a ratio of 1 mmol).

The means for supporting the alkali metal carboxylate or the alkali metal halide together with the carrier is not particularly limited, but for example, an aqueous solution of the alkali metal carboxylate or the alkali metal halide may be supported on the carrier. It can be easily supported by impregnating a carrier and evaporating the water.

[Effect]

In the method of the present invention, since the palladium source substance is supported on the first catalyst material in which antimony oxide is supported on the carrier by impregnating the palladium source substance with a solution of the organic solvent, the existence state of the antimony oxide and the palladium source substance in the carrier is Therefore, by also supporting the vanadium source material on the carrier, metals or oxides of antimony, palladium and vanadium are suitably produced on the carrier through the reduction treatment, resulting in extremely high It is possible to easily and reliably obtain an active and highly stable catalyst for producing unsaturated diesters.

〔Example〕

Examples of the present invention will be described below, but the present invention is not limited thereto.

Example 1 Preparation of impregnated catalyst Weighed out 6.43 g of antimony trichloride and added it to a concentration of 3.
It was dissolved in a 6% by weight aqueous hydrochloric acid solution. All of this solution was transferred to a carrier made of titania in the form of a round sphere with a diameter of 3 mm.
(Manufactured by Sakai Chemical Co., Ltd.) 1 (When added to an evaporating dish containing 10 g, almost the entire amount of the solution was impregnated into the carrier. After the hydrochloric acid aqueous solution was evaporated while stirring the carrier in the evaporating dish on a hot water bath. The mixture was dried overnight at 60° C. in a dryer, thereby obtaining a catalyst material carrier in which antimony chloride was supported on the carrier.

This catalyst material was put into a neutralizing solution 150- consisting of an aqueous ammonium carbonate solution having a concentration of 20% by weight, and a neutralization reaction was carried out for 30 minutes. Thereafter, the catalyst material was recovered by filtration through a 20-mesh stainless steel mesh.
It was washed 10 times with 150° C. pure water to remove ammonium chloride produced by the neutralization reaction. For each wash, a volume of 30ml containing 150ml of 80°C pure water was used.
The catalyst material after the neutralization reaction was added to a beaker of 0-0.5° C. and kept at a temperature of 80° C. for 30 minutes with occasional stirring, and then filtered through a 20-mesh stainless steel mesh to take out the catalyst material.

After the washing process is completed, the catalyst material is placed in an evaporation dish and heated to 70°C.
The mixture was dried overnight, and then calcined at 500° C. for 3 hours under atmospheric pressure, thereby obtaining a first catalyst material in which antimony oxide was supported on a carrier. This will be referred to as "first catalyst material A."

Support of palladium source material: 20g of this first catalyst material is placed in an evaporating dish, and on a water bath, a chloroform solution containing 0.844g of palladium acetate is added to impregnate it, and the remaining chloroform is evaporated. Palladium acetate was supported.

Supporting Vanadium Source Material After that, an aqueous solution in which 0.440 g of ammonium metavanadate was dissolved was added to support ammonium metavanadate in the same manner, and then this was dried at 90° C. overnight.

Calcining Treatment The catalyst material obtained as described above was calcined in a Matsufuru furnace at 500° C. for 3 hours under atmospheric pressure. The catalyst material obtained here is referred to as "second catalyst material A."

Reduction Treatment This second catalyst material 8 was subjected to reduction treatment in a hydrogen stream at 200°C for 2 hours and then at 400°C for 2 hours to obtain a catalyst containing antimony, palladium, and vanadium. This will be referred to as "catalyst A."

Co-catalyst support treatment Potassium acetate 0.40 g and senlum chloride 2.00 g
g into an evaporating dish, add 3.5 g of pure water to dissolve it completely, and add 10.00 g of the above catalyst to this aqueous solution.
was impregnated with the aqueous solution, and further heated on a hot water bath to evaporate water to prepare a catalyst on which potassium acetate and cenlum chloride, which are co-catalysts, were supported. This is called "catalyst IJ.

Example 2 20 g of the first catalyst material obtained in Example 1 was weighed out and placed in an evaporating dish, and 1.15 g of palladium acetylacetonate and 0.997 g of vanadium oxide acetylacetonate were added. An acetone solution prepared by dissolving the above was added thereto, and the acetone was evaporated on a hot water bath to support the palladium source material and the vanadium source material to obtain a catalyst material.

This will be referred to as "second catalyst material B." This second catalyst material B
, at 200℃ under nitrogen flow for 3 hours, and at 400℃ under air flow.
The organic components were completely removed by baking for 3 hours.

Thereafter, in the same manner as in Example 1, reduction treatment and co-catalyst supporting treatment were performed to obtain a catalyst. This is called "catalyst ■".

Example 3 4.11 g of antimony oxide and 12.3 g of tartaric acid were weighed out and dissolved in 35 ml of water. All of this solution was transferred to the same titania carrier 100 as in Example 1.
g in an evaporating dish, evaporate the water on a hot water bath, then dry it at 70°C overnight, and then put it in an air atmosphere for 500°C.
A calcination treatment was performed at ℃ for 3 hours, thereby obtaining a catalyst material on which antimony oxide was supported. This will be referred to as "first catalyst material C."

20 g of this first catalyst material C was weighed out, palladium acetate and ammonium metavanadate were supported in the same manner as in Example 1, and dried, calcined and reduced in the same manner as in Example 1. A catalyst was obtained by carrying out a catalyst supporting treatment. This is called "catalyst ■".

Comparative Example 1 20 g of the first catalyst material A obtained in Example 1 was taken and placed in an evaporating dish, and 0.8 g of palladium nitrate was placed on a hot water bath.
66 g and ammonium metavanadate 0.440
An aqueous solution prepared by dissolving G in water was added to impregnate the first catalyst material 8, and then this catalyst material was dried at 90° C. overnight, and fired in the same manner as in Example 1.

The catalyst material thus obtained was subjected to reduction treatment and co-catalyst supporting treatment in the same manner as in Example 1 to prepare a catalyst. This is called "catalyst ■".

Comparative Example 2 6.43 g of antimony trichloride and 3.3 g of palladium chloride
3 g of ammonium metavanadate and 2.20 g of ammonium metavanadate were dissolved in an aqueous solution of hydrochloric acid with a concentration of 36% by weight, and the entire solution was added to an evaporating dish containing 100 g of a carrier made of titania similar to that in Example 1. Ta. As a result, almost the entire amount of the solution was impregnated into the carrier, but since there was a small amount of solution that remained unimpregnated, it was heated on a hot water bath to evaporate a part of the aqueous hydrochloric acid solution to completely impregnate the carrier. The obtained product was dried in a dryer at 60° C. for 5 hours.

20 g of this catalyst material was put into a neutralizing solution 30 consisting of an aqueous ammonium carbonate solution with a concentration of 20% by weight, and a neutralization reaction of antimony chloride, palladium chloride, and residual hydrogen chloride was carried out for 30 minutes. The catalyst material is collected by filtration using a stainless steel mesh.
This was washed 10 times with 30 ml of 80°C pure water to remove ammonium chloride produced by the neutralization reaction.

The catalyst material obtained here was placed in an evaporating dish and dried at 70°C overnight, and then calcined at 500°C for 3 hours under atmospheric pressure. Further, in the same manner as in Example 1, reduction treatment and cocatalyst supporting treatment were performed to prepare a catalyst. this"
"Catalyst V".

<Evaluation of catalyst> Catalyst 1- prepared according to the above examples and comparative examples
Regarding V, the activity as a catalyst in the reaction of producing an unsaturated diester by subjecting a mixed gas containing a conjugated diene, an organic carboxylic acid, and oxygen to a gas phase flow reaction was evaluated according to the following procedure.

Approximately 10m1 of each catalyst! , diameter 2Qmm, total length 5Qcm
A heat-resistant glass reaction tube is filled with nitrogen gas at a rate of 5.
5! The temperature was raised to 180°C while supplying at a rate of . Thereafter, acetic acid vaporized in a vaporizer was fed at a rate of 5.36 g/hour, and butadiene and air were fed at a rate of 1.01/hour and 1.51/hour, respectively, to cause a reaction.

The main product obtained by this is 1,4-diacetoxy-
2-butene, 3,4-diacetoxy-1-butene, 1-
They were acetoxy-1,3-butadiene and carbon dioxide. 25 hours after starting the reaction, and 10
The situation after 0 hours is shown in Table 1. In Table 1,
The production amount of diacetquin butene is the sum of the production amounts of 1,4-diacetoxy-2-butene and 3,4-diacetoxy-1-butene, and the unit of production amount of diacetquin butene is ( g/i-catalyst/time).

Table 1 [Effects of the Invention] As described above, according to the method of the present invention, a palladium source material is supported on a first catalyst material in which antimony oxide is supported on a carrier by impregnating it with a solution of its organic solvent. Therefore, by supporting the vanadium source material on the carrier, the desired antimony, palladium, and vanadium can be obtained through reduction treatment. It is possible to reliably prepare a catalyst for producing an unsaturated diester as a component with high reproducibility. Furthermore, since this catalyst has high activity and excellent stability, it becomes possible to produce unsaturated diesters at low cost, and its industrial significance is extremely large.

Claims (1)

[Scope of Claims] 1) A catalyst containing antimony, palladium, and vanadium as essential components, which is used in a gas phase flow reaction of a mixed gas containing a conjugated diene, an organic carboxylic acid, and oxygen to produce an unsaturated diester. In the preparation method, antimony oxide, palladium source material and 1. A method for preparing a catalyst for producing an unsaturated diester, which comprises obtaining a catalyst material on which a vanadium source substance is supported, and subjecting this catalyst material to a reduction treatment.