JPS6146464B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides the following method: 1.
The present invention relates to a method for producing diacetoxybutene by acetoxylating 3-butadiene. Diacetoxybutene, particularly 1,4-diacetoxybutene, is industrially useful as a raw material for tetrahydrofuran or for 1,4-butanediol, which is a component of polybutylene terephthalate. The method of using a palladium-based solid catalyst in the production of diacetoxybutene by reacting 1,3-butadiene with molecular oxygen and acetic acid is well known (Japanese Patent Publication No. 50-23008, Japanese Patent Publication No. 52
−12171). In addition, a method of using a rhodium-based solid catalyst as a catalyst for the above reaction is disclosed in JP-A-51-
108010, JP-A-52-139004, etc. In these methods, solid catalysts containing rhodium and tellurium or selenium are used, which have superior activity and selectivity to 1,4-diacetoxybutene compared to palladium-based catalysts. However, the above-mentioned rhodium-based solid catalyst has the disadvantage that rhodium is eluted into the reaction solution as the reaction progresses, causing a rapid decrease in activity, and further improvements are required in order to commercialize it. be. The present inventors investigated rhodium-based solid catalysts that cause less elution of rhodium into the reaction solution, and found that at least one selected from rhodium compounds, antimony compounds, arsenic compounds, and thallium compounds was supported on a carrier, and reduction treatment was performed. The inventors have discovered that when the reaction is carried out using the prepared solid catalyst, the elution of rhodium into the reaction solution can be suppressed to a very small amount, leading to the present invention. The present invention will be explained in detail below. The catalyst used in the method of the present invention is a solid catalyst in which at least one of a rhodium compound, an antimony compound, an arsenic compound, and a thallium compound is supported on a carrier and subjected to a reduction treatment. The solid catalyst includes inorganic acid salts such as rhodium chloride, rhodium nitrate, rhodium sulfate, carboxylic acid salts such as rhodium acetate, inorganic compounds such as rhodium hydroxide and rhodium oxide, sodium hexachlororhodium, ammonium hexachlororhodium, rhodium chloropentaammine, Complex compounds such as chlorohexaammine rhodium, potassium hexacyano rhodium, and trichlorotripyridine rhodium are used as rhodium sources, and antimony chloride, antimony oxide, antimony sulfide, antimony metal, arsenic oxide, thallium oxide, thallium nitrate, thallium acetate, etc. are used as rhodium sources. Prepared for use as a source of arsenic or thallium. Suitable carriers include activated carbon, silica, silica alumina, alumina, pumice, diatom, etc., and activated carbon and silica are particularly preferably used. These carriers may be used as commercially available products, but good results are often obtained when used after heat treatment or acid treatment with hydrofluoric acid, nitric acid, etc. according to known methods. . In supporting the catalyst component on the carrier,
Each component may be supported sequentially or two or more components may be supported simultaneously. The catalyst components are supported on the carrier.
The reaction can be carried out by dissolving a compound containing the catalyst component in a solvent such as water or an acid, and using a well-known method such as an impregnation method, a dipping method, an evaporation method, a precipitation method, or a cation exchange method. The amount of catalyst components supported on the carrier can be varied over a wide range, with rhodium ranging from 0.1 to 20
Weight %, preferably 0.5 to 5 weight %, antimony, arsenic or thallium 0.05 to 30 as a single unit
% by weight, preferably 0.1-5% by weight. Also, the ratio of rhodium to antimony, arsenic or thallium is 0.01 per gram atom of rhodium.
~10 gram atoms, preferably 0.05-5 gram atoms. In the method of the present invention, in order to increase the activity of the catalyst, a reduction treatment is performed after supporting the catalyst component on a carrier. The reduction treatment can be carried out by a known reduction method using a reducing agent such as hydrogen, methanol, formalin, or hydrazine. The method of the present invention uses the above catalyst to create a suspended bed,
It is carried out by reacting 1,3-butadiene with molecular oxygen and acetic acid batchwise or continuously under defined reaction conditions in a gas or liquid phase in a flowing or fixed bed. Each reaction raw material may contain a diluent that is inert to the reaction, and there is no problem even if an inert gas such as nitrogen or argon or water coexists in the reaction system. Furthermore, when this reaction is carried out in a liquid phase, acetic acid may be used in excess as a catalyst, or a solvent inert to the reaction such as a saturated hydrocarbon or ester may be used. When carrying out this reaction in the gas phase, it is desirable to avoid gas compositions within the explosive range. In carrying out this reaction,
Molar ratio of acetic acid to 1,3-butadiene 3~
100, preferably 5 to 50, the reaction temperature is 50 to 150°C when carried out in a liquid phase, 100 to 250°C when carried out in a gas phase, and the reaction pressure is appropriately within the range of normal pressure to about 10 atm. selected. Next, the present invention will be explained in more detail with reference to Examples. Example 1 500 g of crushed coconut shell charcoal of 4 to 6 meshes, 356 g of concentrated nitric acid, and 830 g of water were charged into a flask with an internal volume of 3 and equipped with a reflux condenser, and heated under reflux for 4 hours. After standing overnight, the activated carbon was separated and dried in a rotary evaporator at 80° C. and 30 mmHg for 3 hours to prepare an activated carbon carrier. 3.9 g of an acetic acid solution of rhodium acetate (3.78 mg atoms of rhodium alone) and antimony trichloride
0.258 g was dissolved in 30 ml of 6N hydrochloric acid, 13 g of the activated carbon carrier was added thereto, the mixture was left to stand for 30 minutes, and then evaporated to dryness using a rotary evaporator. Next, the temperature was raised to 100°C under a nitrogen flow, then switched to a hydrogen flow, raised to 150°C and held for 2 hours, raised to 300°C and held for 2 hours, and raised to 400°C for 2 hours. After holding for a period of time, the catalyst was activated by cooling under a nitrogen stream. 10 ml (approximately 4.7 g) of the above catalyst was packed into a heat-resistant glass reactor with an inner diameter of 13.9 mm, and 20 ml of acetic acid was charged.
Acetic acid, butadiene and oxygen were immersed in a constant temperature bath at 670 mmole/hr and 118 m from below the catalyst layer, respectively.
The reaction was carried out by feeding at a rate of mole/hr and 78 mmole/hr. After a predetermined period of time had elapsed, the reaction solution was collected, the product was quantified by gas chromatography, and the rhodium eluted into the reaction solution was quantified by atomic absorption spectrophotometry. The results are shown in Table 1. Example 2 A homogeneous solution obtained by dissolving 0.112 g of arsenic oxide in a mixed solvent of 30 ml of ethanol and 30 ml of 30% by weight nitric acid and mixing it with 2.93 g of an acetic acid solution of rhodium acetate (2.82 mg atoms as rhodium alone) was used. 13 g of the activated carbon carrier prepared in 1 was soaked and evaporated to dryness using a rotary evaporator. The obtained catalyst was placed under nitrogen gas flow containing 8% methanol by volume.
Activation was performed by reduction treatment at 200°C for 2 hours and at 400°C for 4 hours. Example 1 using 1.0 ml (4.39 g) of the above catalyst
The reaction was carried out in the same manner. The results are shown in Table-1. Example 3 Using 0.259 g of thallium oxide instead of arsenic oxide, the amount of rhodium acetate acetic acid solution used was 3.9 g.
A catalyst was prepared and activated in the same manner as in Example 2, except that the amount of rhodium was changed to 3.78 mg atoms as a simple substance of rhodium. A reaction was carried out in the same manner as in Example 1 using 10 ml (4.67 g) of the obtained catalyst. The results are shown in Table-1. Comparative Example 1 7.8 g of acetic acid solution of rhodium acetate (7.55 mg atoms as rhodium alone) and 0.603 g of tellurium dioxide
was dissolved in 50 ml of 6N hydrochloric acid, 50 ml (25.9 g) of the activated carbon carrier prepared in Example 1 was added, and the mixture was evaporated to dryness using a rotary evaporator. The obtained catalyst was activated by reduction treatment under a hydrogen stream at 150°C for 2 hours, at 400°C for 2 hours, and further at 500°C for 2 hours. A reaction was carried out in the same manner as in Example 1 using 10 ml (4.46 g) of the above catalyst. The results are shown in Table-1. Comparative Example 2 0.294 g of tellurium dioxide was dissolved in 50 ml of 6N hydrochloric acid and mixed with 6.36 g of an acetic acid solution of rhodium acetate (6.15 mg atoms as rhodium alone) to form a homogeneous solution. Add silica particles (manufactured by Fuji Davison Co., Ltd.) to this solution.
iD-8) 50 ml (21.1 g) was immersed and evaporated to dryness using a rotary evaporator. 20 ml of the obtained catalyst was heated at 150°C for 1 hour and at 300°C for 2 hours under a stream of steam.
Activation was performed by time reduction treatment. Example 1 using 4.39 g (about 10 ml) of the above catalyst
The reaction was carried out in the same manner. The results are shown in Table-1. 【table】

Claims (1)

[Claims] 1 Rhodium compounds and antimony compounds,
1,3-Butadiene is reacted with molecular oxygen and acetic acid in the presence of a solid catalyst which has been subjected to a reduction treatment, in which at least one selected from an arsenic compound and a thallium compound is supported on a carrier. Method for producing acetoxybutene.