JPH07324046A - Production of mixture composed of cyclohexanol and cyclohexanone - Google Patents

Abstract

PURPOSE:To easily obtain the compounds useful as, e.g. raw materials for synthesizing adipic acid in a high yield, by mixing cyclohexene, water and rhodium iodide under heating. CONSTITUTION:This mixture composed of cyclohexanol and cyclohxanone is obtained by mixing cyclohexene, water and rhodium iodide at 140 deg.C or so for 5 hr. For this method, since a dehydrogenation reaction is conducted under hydration, any catalyst for the hydration need not be added and the objective mixture can be obtained favorably. Adipic acid is one of the raw materials for 6,6-nylon.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a mixture of cyclohexanol and cyclohexanone, and this mixture of cyclohexanol and cyclohexanone synthesizes adipic acid, which is one of the raw materials for 6,6-nylon. It is a raw material for

[0002]

2. Description of the Prior Art 6,6-Nylon is composed of hexamethylenediamine (NH ₂ (CH ₂ ) ₆ NH ₂ ) and adipic acid (HOOC (CH ₂ ) ₄ COO.
H) and are polymerized. One method of synthesizing adipic acid in large quantities is from benzene (C ₆ H ₆ ) to cyclohexene (C ₆ H ₁₀ ) and from cyclohexene (C ₆ H ₁₀ ) to cyclohexanol (C ₆ H ₁₁ -OH). Use reaction. From this benzene (C ₆ H ₆ ), cyclohexene (C ₆ H _6
The reaction producing ₁₀ ) is shown in the following chemical formula 1.

[0003]

[Chemical 1]

As shown in the chemical reaction formula of Chemical formula 1, benzene (C ₆ H ₆ ) is partially hydrogenated to produce cyclohexene (C ₆ H ₁₀ ).
To get Ruthenium (Ru) is mentioned as a catalyst for this reaction. Ruthenium is used as fine particles as a metal compound such as zinc and iron. Cyclohexene (C ₆ H ₁₀ ) was suspended in the oil phase by suspending the catalyst in an aqueous phase together with benzene, heating to 100 to 180 ° C., separating the produced cyclohexene into an oil phase and suppressing successive hydrogenation.
To get

[0005] The obtained cyclohexene (C ₆ H ₁₀₎ cyclohexanol by hydration reaction shown in the following reduction 2 (C ₆
H ₁₁ -OH). The reaction of obtaining cyclohexanol (C ₆ H ₁₁ -OH) from cyclohexene (C ₆ H ₁₀ ) by a hydration reaction is the reverse of the above-mentioned reaction, in which cyclohexene (C ₆ H ₁₀ ) in the oil phase is in the liquid phase. with hydration, obtaining cyclohexanol (C ₆ H ₁₁ -OH).

[0006]

[Chemical 2]

As a catalyst for this reaction, high-silica zeolite or the like is known, and this catalyst is added and cyclohexene (C ₆ H ₁₀ ) and water are heated to react. in this case,
The catalyst is suspended in the aqueous phase. By the way, the conversion of this cyclohexanol (C ₆ H ₁₁ —OH) per pass is about 18% at a reaction temperature of 150 ° C. and about 9% at 180 ° C.
A selectivity of 9% or more is obtained.

[0008]

However, the hydration reaction of cyclohexene (C ₆ H ₁₀ ) using a high silica zeolite reached a peak at a conversion of about 20%. this is,
This was because there was a reverse reaction from cyclohexanol (C ₆ H ₁₁ -OH) to cyclohexene (C ₆ H ₁₀ ) and there was an equilibrium state.

Therefore, by the dehydrogenation reaction shown in the following Chemical formula 3, cyclohexanol (C ₆ H ₁₁ -OH) equilibrated by the hydration reaction shown in the above Chemical formula 2 is further added to cyclohexanone (C ₆ H ₁₀ = O), the cyclohexene (C ₆ H
₁₀ ) and cyclohexanol (C ₆ H ₁₁ -OH) by shifting the equilibrium state to increase the total amount of cyclohexanol (C ₆ H ₁₁ -OH) and cyclohexanone (C ₆ H ₁₀ = O). did.

[0010]

[Chemical 3]

[0011] As a result, cyclohexanol (C ₆ H ₁₁ -
Since both OH) and cyclohexanone (C ₆ H ₁₀ = O) can be used as raw materials for adipic acid, the amount corresponding to the amount of cyclohexanone (C ₆ H ₁₀ = O) increases and the yield improves. Will be done.

[0012] Therefore, the present inventor has conducted various studies on hydration catalysts and dehydrogenation catalysts, and found that among rhodium halide catalysts, rhodium iodide (RhI ₃ ) has a special reaction. The present invention has been obtained.

The object of the present invention is to obtain a simple process for producing a mixture of cyclohexanol and cyclohexanone as a raw material for synthesizing adipic acid from cyclohexene (C ₆ H ₁₀ ) in a high yield. And

[0014]

In the method for producing a mixture of cyclohexanol and cyclohexanone according to the present invention described in claim 1, cyclohexene, water and rhodium iodide (RhI ₃ ) are heated and mixed.

In the method for producing a mixture of cyclohexanol and cyclohexanone according to the invention described in claim 2, cyclohexene, water, and rhodium iodide (RhI ₃ )
And are heated and mixed at around 140 ° C. for 5 hours.

[0016]

In the present invention, as a result of searching various catalysts for carrying out the dehydrogenation reaction shown in Chemical formula 3, rhodium iodide (RhI
_{It was found that 3} ) acts as a catalyst for both the hydration reaction shown in Chemical formula 2 and the dehydrogenation reaction shown in Chemical formula 3.

Therefore, in the case of mixing cyclohexene of the present invention with water and rhodium iodide (RhI ₃ ) by heating,
As shown in the chemical reaction formula shown in the following Chemical formula 4, by carrying out the dehydrogenation reaction while carrying out the hydration reaction, it is not necessary to add another catalyst for carrying out the hydration reaction, and the cyclohexene is satisfactorily obtained. (C ₆ H ₁₀ ) to cyclohexanol (C ₆ H 10
₁₁ -OH) to be able to obtain a mixture of cyclohexanone _{(C 6 H 10 = O)} .

[0018]

[Chemical 4]

A specific reaction using rhodium iodide (RhI ₃ ) as a catalyst is carried out at a temperature of 10 while stirring cyclohexene (C ₆ H ₁₀ ) and water with rhodium iodide (RhI ₃ ).
By heating to 0 to 180 ° C., a mixture of cyclohexanol (C ₆ H ₁₁ —OH) and cyclohexanone (C ₆ H ₁₀ ═O) can be obtained.

[0020] Incidentally, if the heating temperature is lower than 100 ° C. Cyclohexene (C ₆ H ₁₀₎ cyclohexanol (C ₆ H
_11- OH) does not proceed well. Also, 180
℃ not only increases the heating costs of the reactor itself exceeds the reverse reaction becomes active, from cyclohexanol (C ₆ H ₁₁ -OH) cyclohexene (C ₆ H _10), remove the termination.

A preferable heating temperature is around 140 ° C., and the highest yield can be obtained. As for the holding time, by holding for 5 hours, a mixture of cyclohexanol (C ₆ H ₁₁ —OH) and cyclohexanone (C ₆ H ₁₀ ═O) can be obtained in a yield of 33% by weight. this is,
This is about twice as much as that using a catalyst that only performs a normal hydration reaction (producing only cyclohexanol).

[0022]

【Example】

Example 1. 0.2 ml of cyclohexene (C ₆ H ₁₀ ),
The mixture was mixed with 1.3 ml of water, mixed with various metal halide catalysts (0.79 × 10 ⁻³ mol), heated, and kept at 120 ° C. for 1 hour to analyze the resulting reaction product. did. At the time of analysis, a large amount of ethanol was added to the reaction product to make the oil layer and the water layer into a uniform state and then analyzed. The catalysts used were SnI ₂ , CuBr ₂ , RhBr ₃ and Sb.
There are six types of I ₃ , RhI ₃ , and ZrOCl ₂ .

FIG. 1 is a diagram showing the results of analyzing the reaction products obtained with individual catalysts. In the figure, the shaded area represents the weight% of cyclohexanol (C ₆ H ₁₁ —OH), and the white area represents the weight% of cyclohexanone (C ₆ H ₁₀ ═O 2). As shown in FIG. 1, with rhodium iodide (RhI ₃ ),
Cyclohexanol (C ₆ H ₁₁ -OH) is 8 wt%, cyclohexanone (C ₆ H ₁₀ = O) is 5 wt%, contains a total of 13% by weight, in other catalytic cyclohexanol (C ₆ H ₁₁ - O
It was found that only H) was synthesized.

From these results, rhodium iodide (RhI
It was found that ₃ ) acts as a catalyst for both the hydration reaction and the dehydrogenation reaction. This rhodium iodide (Rh
Verifying the optimal conditions for generation of I ₃₎ by cyclohexanol (C ₆ H ₁₁ -OH) and cyclohexanone (C ₆ H ₁₀ = O) mixtures.

Example 2. Cyclohexene 0.2 ml
, 1.3 ml of water, rhodium iodide (RhI ₃ )
Heat while mixing with 0.79 × 10 ⁻³ mol,
Hold at 0 ° C. for 5 hours. As a result of analyzing the obtained reaction product, it was found that cyclohexanol (C ₆ H ₁₁ —OH) and cyclohexanone (C ₆ H ₁₀ ═O) were contained. Results This was further analyzed in detail, cyclohexanol (C ₆ H ₁₁ -
17% by weight of OH) and 1% of cyclohexanone (C ₆ H ₁₀ = O).
It was found that 6% by weight, a total of 33% by weight, was contained.

As described above, rhodium iodide (RhI
_{When 3} ) is used as a catalyst for hydration of cyclohexene, not only cyclohexanol but also cyclohexanone is produced at the same time. Since the reaction shifts from cyclohexanol to cyclohexanone, the equilibrium between cyclohexene and cyclohexanol shifts, and the combined yield of cyclohexanol and cyclohexanone has twice the conventional capacity.

[0027]

INDUSTRIAL APPLICABILITY As described above, the present invention, in which cyclohexene of the present invention, water and rhodium iodide (RhI ₃ ) are heated and mixed, by performing a dehydrogenation reaction while performing a hydration reaction, Cyclohexene (C ₆ H
_{From 10} ) it is possible to obtain a mixture of cyclohexanol (C ₆ H ₁₁ —OH) and cyclohexanone (C ₆ H ₁₀ ═O).
This mixture can be used as a raw material for adipic acid, which is one of raw materials for 6,6-nylon, and has high industrial utility value.

In particular, when cyclohexene, water and rhodium iodide (RhI ₃ ) are heated and mixed at about 140 ° C. for 5 hours, a catalyst (only produces cyclohexanol) for performing only a normal hydration reaction is produced. The effect is that a mixture of cyclohexanol (C ₆ H ₁₁ —OH) and cyclohexanone (C ₆ H ₁₀ ═O) can be obtained in a yield of 33% by weight, which is about twice the amount used.

[Brief description of drawings]

FIG. 1 is a diagram showing the results of analysis of an oil phase obtained by a cyclohexene hydration reaction.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // C07B 61/00 300

Claims (2)

[Claims] 1. A method for producing a mixture of cyclohexanol and cyclohexanone, which comprises heating and mixing cyclohexene, water and rhodium iodide (RhI ₃ ). 2. A method for producing a mixture of cyclohexanol and cyclohexanone, which comprises heating and mixing cyclohexene, water and rhodium iodide (RhI ₃ ) at around 140 ° C. for 5 hours.