JPS62258335A - Production of methyl isobutyl ketone - Google Patents

Abstract

PURPOSE:To obtain the aimed compound in high yield by simple operation, by using a catalyst containing palladium supported on a carrier consisting of alumina and a specific metal oxide, e.g. calcium oxide, etc., in reacting acetone with hydrogen to produce the titled compound. CONSTITUTION:Acetone is reacted with hydrogen in the presence of a catalyst prepared by supporting normally 0.01-5.0wt%, preferably 0.05-1.0wt% palladium on a carrier consisting of alumina and one or more metal oxides selected from calcium oxide, magnesium oxide and strontium oxide normally at 80-250 deg.C, preferably 120-200 deg.C under atmospheric pressure - 50atm, preferably 10-30atm pressure, preferably in the liquid phase to stably afford the aimed methyl isobutyl ketone useful as a raw material for organic solvents, coating materials, stabilizers, etc., in high yield for a long period using the above- mentioned readily preparable catalyst having high activity, selectivity and stability as well as long life.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing methyl isobutyl ketone in a one-step reaction using acetone and hydrogen as raw materials.

Methyl isobutyl ketone (hereinafter referred to as MIBK) is useful as a raw material for organic solvents, paints, stabilizers, and the like.

<Conventional technology> MIBK usually uses acetone and hydrogen as raw materials.

It is manufactured industrially using the following three-stage method.

The feature of this three-step method is that the steps of condensation, dehydration, and hydrogenation shown in the above formula are carried out sequentially.
Diacetone alcohol is mixed by reacting it in a liquid phase at 0°C and normal pressure, and the diacetone alcohol obtained by first condensation is reacted in a liquid phase in the presence of an acid catalyst such as sulfuric acid or phosphoric acid to a concentration of 100 to 120 'C to perform a dehydration reaction and obtain menthyl oxide. Subsequently, this menthyl oxide is separated and purified, and then hydrogenated in the presence of a lye-nickel catalyst or the like to produce MIBK.

This method is widely used industrially.

There are three reaction steps: condensation, dehydration, and hydrogenation, and each step requires separation and purification of intermediates such as diacetone alcohol X oxide, making the operation complicated. Furthermore, since the condensation reaction from acetone to diacetone alcohol is an equilibrium reaction, there is a problem that the conversion rate is as low as about 15%.

To this end, studies are being conducted to produce methyl isobutyl ketone in one step from acetone and hydrogen. This process is equilibrium-friendly and can increase feed conversion per pass.

It is economically advantageous compared to the three-stage method. Conventional methods for producing MIBK by such a casting method include a method using an acid type ion exchange resin and palladium-carbon as a catalyst (German Patent No. 1238453), and a method using a catalyst in which palladium is supported on zirconium phosphate. (Japanese Patent Publication No. 49-6994), method using a catalyst in which palladium is supported on H-type zeolite (Japanese Patent Publication No. 46-2643)
Publication No.) etc. have been reported.

However, in these conventional methods, since a resin is used, the reaction temperature cannot be raised, the raw material conversion rate is low, and the preparation of the catalyst is complicated. Alternatively, MIBK has the disadvantage of a low yield, and industrially satisfactory results have not been obtained.

<Problem that the invention seeks to solve> The present invention uses acetone and hydrogen as raw materials.

In the method for producing MIBK, the disadvantages of the conventional method, such as low raw material conversion rate, low yield of MIBK, and complicated catalyst preparation, have been improved, and MIBK can be produced in high yield with simple operations. The aim is to obtain at a high rate.

Means for Solving the Problems The present invention relates to a method for producing methyl isobutyl ketone by reacting acetone and hydrogen.

Alumina and calcium oxide, MA oxide!゛I-Shium.

The present invention relates to a method for producing methyl isobutyl ketone, characterized by using a catalyst in which palladium is supported on a carrier comprising one or more metal oxides selected from strontium oxide.

The present invention will be specifically explained below.

The catalyst used in the method of the present invention has palladium supported on a carrier consisting of alumina and one or more metal oxides selected from calcium oxide, magnesium oxide, and strontium oxide. The carrier used in the method of the present invention is usually produced by dipping alumina in an aqueous solution of calcium acetate or the like, followed by firing.Gamma alumina is preferably used as the 3° alumina. As the aqueous solution of calcium, magnesium, and strontium, aqueous solutions of acetates, nitrates, and cealates of these metals are used, and preferably aqueous solutions of acetates of these metals are used. Firing is usually carried out at a temperature of 300 to 600°C. Calcination at temperatures below 300°C or above 600°C will only result in low activity.

The amount of palladium supported is usually 0.01 to 5. ON is 1%, preferably 0.05 to 1.0% by weight.

If it is less than 0.01% by weight, good activity cannot be obtained;
If the amount exceeds % by weight, the supported palladium will not be used effectively.

The catalyst used in the method of the present invention is usually produced by immersing alumina in an aqueous solution such as calcium acetate, calcining it, and then supporting palladium. It can also be manufactured by immersing it in an aqueous solution and firing it.

As for the reaction form of the method of the present invention, a so-called fixed bed flow reaction may be adopted in which the catalyst is packed in an adiabatic or isogaster reactor and acetone and hydrogen are passed therein, or the catalyst may be suspended in acetone. The reaction may be carried out by blowing hydrogen into the reaction mixture. When the reaction is carried out in a fixed bed flow reaction, the reaction may be carried out in the gas phase or in the liquid phase, but preferably the reaction is carried out in the liquid phase. When the reaction is carried out using the suspension method, the two reactions may be carried out either batchwise or continuously.At temperatures above 0, the reaction rate decreases, and at temperatures higher than this temperature, high condensation products of acetone increase. .

The reaction pressure is usually atmospheric pressure to 50 atm, and is preferably 10 to 30 atm, although it depends on the reaction temperature.

In the method of the present invention, the catalyst can be easily prepared, and the catalyst has high activity and good two-selectivity. Furthermore, the catalyst is highly stable and has a long lifespan, so MIB can be produced stably for a long time and in high yield.
K can be produced.

The method of the present invention will be explained in more detail below using examples, but the scope of the present invention is not limited thereby.

<Example> Example 1゜Alumina pellet (Sumitomo Aluminum WKHD-24) lo
1 mol/liter of O- in aqueous acetic acid solution 500
- Soaked in water for 3 hours. Then take out this pellet 4
It was fired at 00°C.

This carrier is immersed in an aqueous solution of palladium chloride.

After reduction with dorazine and sintering at 300°C. The amount of palladium supported was 0,1M%.

This catalyst 100- was packed into a vertically arranged reaction tube with an inner diameter of 28 mm, and the acetonate was heated at 1589/hr (LH3V = 2) under conditions of a temperature of 160°C and a pressure of 20 Kp/J.
.

Hydrogen was introduced into the reactor at a supply rate of 256N, //'' to carry out the reaction, and the results shown in Table 1 were obtained.The reaction results were obtained by gas chromatography analysis of the reaction solution.

Table 1 Example 2. ~4゜Example 1. Catalysts were prepared using the compounds listed in Table 2 instead of the calcium acetate used in Example 1, and MIBK synthesis reactions were carried out using these catalysts. The catalyst preparation conditions and reaction conditions were all the same as those described in Example 1, except that the compounds listed in Table 2 were used in place of calcium acetate.

Table 2 Example 5. ~7゜Example 1.1 Preparation method described [Using the catalyst thus prepared, a reaction was carried out under the reaction conditions shown in Table 3.
The results shown in the table were obtained. Note that the reaction was carried out under the same conditions as described in Table 3 (Example 1.D except for the reaction conditions shown).

Table 3 (Note) The values in Table 3 are the values 10 hours after the start of the reaction.

Example 8 100 tons of acetone and Example 1 were placed in an autoclave with an internal volume of 200 mm and equipped with a magnetic stirrer. The catalyst prepared by the method described in 1 was pulverized and powdered catalyst 2f was added. Heat the autoclave to 160°C.

Hydrogen was added to the autoclave so that the pressure within the autoclave was 20 kg/Cj, and the reaction was carried out with stirring. Hydrogen consumed as the reaction progressed was continuously replenished, and the total pressure was always maintained at 20 V4/i. After carrying out the reaction for 2 hours, the autoclave was cooled, the reaction product was taken out, hydrogen and the catalyst were separated, and then analyzed by gas chromatography to obtain the following results.

Acetone conversion rate...45°7% MIBK
Selection rate...93.1% IPA selection rate...1.5% DI BK selection rate...
...... 264% Comparative Example 1゜Alumina pellets (Sumitomo Aluminum KHD-24) +00
Tnl was immersed in an aqueous solution of palladium chloride, reduced with hydrazine, and then calcined at 300°C to prepare a catalyst. The amount of palladium supported was 0.1% by weight.

MIBK synthesis reaction was carried out using this catalyst +00 d. The reaction conditions other than the catalyst were the same as those described in Example 1.

Sampling was performed 10 hours after the start of the reaction.

The reaction solution was analyzed by gas chromatography, and the following results were obtained.

Acetone conversion rate...I9.8% IPA selectivity...9.6% MIBK selectivity...86
, 4% DIBK selectivity...3.0% <Effect of the invention> As described above, according to the present invention, alumina and one or more selected from calcium oxide, magnesium oxide, and strontium oxide are combined. By reacting acetone with hydrogen in the presence of a catalyst in which palladium is supported on a carrier consisting of a metal oxide, methyl isobutyl ketone can now be obtained in good yield in a single reaction.

Claims (1)

[Claims] In a method for producing methyl isobutyl ketone by reacting acetone and hydrogen, palladium is supported on a carrier consisting of alumina and one or more metal oxides selected from calcium oxide, magnesium oxide, and strontium oxide. A method for producing methyl isobutyl ketone, characterized by using a catalyst.