JP2003327551A - Method for producing indane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that there are various side reactions in the conventional high-temperature reactions for providing indane by dehydrogenation of 3a,4,7,7a-tetrahydroindene (THI) and to provide a method for producing the indane with which the indane is obtained at a low reaction temperature in a high yield. <P>SOLUTION: The method for producing the indane comprises dehydrogenating the THI using a dehydrogenation catalyst containing a metal dehydrogenation catalyst supported on a zeolite carrier having ≥50 Si/Al atomic ratio and a pore structure in which an inlet of a main cavity is a ≥12-membered oxygen ring. Thereby, the side reactions are suppressed to provide the indane from the THI in the high yield. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to 3a, 4, 7, 7a.
The present invention relates to a method for dehydrogenating tetrahydroindene (hereinafter abbreviated as “THI”) to obtain indane useful as a synthetic raw material for pharmaceuticals and chemicals or a metallocene catalyst component.

[0002]

2. Description of the Related Art Research on a method for producing indane by dehydrogenating THI has been conventionally conducted for the purpose of obtaining indane and further for dehydrogenating indane to obtain indene. For example, US Pat.
No. 2,455 discloses a method of providing a two-stage dehydrogenation zone, synthesizing a reaction intermediate from THI in the first dehydrogenation zone, and converting it into indene in the second dehydrogenation zone. Although the reaction intermediate contains indene, indane, etc., indane has not been obtained in high yield.

Further, Japanese Unexamined Patent Publication No. 2000-63298 discloses a method for producing indene from THI as a raw material by a two-step reaction using a metal-based dehydrogenation catalyst such as oxides of nickel, molybdenum and cobalt. ,
It is characterized in that indane is obtained at a concentration of 70% or more in the first stage reaction, while indene is suppressed to 10% or less. It is described that the reason for this is that as the concentration of indene increases, the activity of the catalyst decreases significantly due to coking, which makes continuous operation for a long time difficult. In order to achieve this purpose, the reaction in the first stage is set at a temperature lower than that in the second stage for dehydrogenating indane,
Since a general dehydrogenation catalyst such as used has low catalytic activity at low temperature, it is preferably 400 to 600 ° C., preferably 450.
The temperature is as high as ˜520 ° C. In this way, when the temperature is raised to improve the concentration of indane, a certain amount of indene is inevitably produced (in the example, the reaction at 450 ° C. causes a reaction in the recovered oil). 77.9-84.
(Obtains 0% indane and 3.2-4.7% indene). This leads to reduced activity of the catalyst as described in the specification.

Further, Japanese Patent Laid-Open No. 2001-220359 discloses a method of carrying out a reaction at 50 to 250 ° C. in the presence of a dehydrogenation catalyst for the purpose of obtaining indane from THI. Although the reaction temperature is lowered in order to improve the selectivity of the reaction for forming indane, this method is used at a temperature of 200 ° C. as described in the Examples due to the use of a conventional dehydrogenation catalyst. At the following reaction temperatures, the yield of indane is only in the range of 70% even if the reaction time is as long as 6 to 7 hours. Further, although the flow-type reaction is carried out by raising the reaction temperature to 220 ° C., the selectivity remains in the range of 70% even under the condition that THI vapor is diluted five times with nitrogen gas.

As described above, in the presence of a dehydrogenation catalyst, THI
It is known to convert indane to indane, but in the technology up to now, in order to increase the yield of indane, a reaction at a high temperature is required, and the amount of dehydrogenated to indene increases. There have been problems that the catalytic activity is lowered and THI is decomposed by the polymerization. Further, when the reaction temperature is lowered in order to improve the selectivity of the reaction for forming indane, there is a problem that the indane yield remains low even after a very long reaction time. For that reason, TH
The industrial method for economically and efficiently producing indane from I has not been established.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method capable of obtaining indane in a high yield by sufficiently proceeding the reaction of forming THI to indane even at a low reaction temperature. .

[0007]

Means for Solving the Problems That is, the first aspect of the present invention
Is the dehydration of THI by supporting a metal-based dehydrogenation catalyst such as platinum or palladium on a zeolite carrier having a pore structure with an Si / Al atomic ratio of 50 or more and a main cavity inlet having a 12-membered oxygen ring or more. The method for producing indane is characterized by carrying out a dehydrogenation reaction in the presence of an elementary catalyst.

According to a second aspect of the present invention, in the first aspect of the present invention,
The method for producing indane is characterized in that the zeolite carrier is uncalcined or calcined zeolite which has been dealuminated. A third aspect of the present invention is the indane according to the first or second aspect of the present invention, wherein the metal of the metal-based dehydrogenation catalyst is selected from the group consisting of platinum, palladium, nickel, rhodium and ruthenium. Is a manufacturing method. A fourth aspect of the present invention is the method for producing indane according to any one of the first to third aspects of the present invention, wherein the reaction temperature is 200 ° C. or higher and 350 ° C. or lower.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. (Zeolite support) The simple substance used for the metal-based dehydrogenation catalyst in the present invention is a zeolite having a Si / Al atomic ratio of 50 or more and a pore structure in which the inlet of the main cavity has a 12-membered oxygen ring or more. Zeolites are SiO ₄ tetrahedra and (AlO
₄₎ ^- tetrahedron is crystal of porous bound to 3-dimensional network. Although the pore structure of the zeolite carrier has an important influence on the reaction, the pore size is determined by the structure of the pore inlet. For the purpose of the present invention, it is preferable that the inlet of the main cavity has a pore structure of 12-membered oxygen ring or more. 12
Preferred examples of zeolite having a pore structure of a member oxygen ring are β-type zeolite and Y-type zeolite. When the inlet of the main cavity is an 8-membered oxygen ring or a 10-membered oxygen ring, THI cannot enter the pores, which is not preferable.

(Si / Al atomic ratio) The acid points in the pores are TH
It has been found that it is deeply involved in the isomerization, decomposition and polymerization of impurities such as 5-vinylnorbornene and 5-ethylidenenorbornene contained in I, which is an obstacle to maintaining the catalytic activity for a long time. The acid point concentration corresponds to the Si / Al atomic ratio. The Si / Al atomic ratio range suitable for the purpose of the present invention is 50 or more, more preferably 100 or more, and particularly preferably 200 or more. S
If the i / Al atomic ratio is less than 50, the yield of indane decreases due to a side reaction, which is not preferable. The upper limit of the Si / Al atomic ratio is not particularly limited, but it is preferably determined in consideration of the balance of the labor required for dealumination treatment described later and the economical efficiency of improving the indane yield.

(Dealuminization treatment) Si of zeolite
If the / Al atomic ratio is within the preferable range, the carrier can be used as it is, but it can be adjusted to the preferable range by performing dealumination treatment. The dealumination treatment can be performed on both the Si / Al atomic ratio of less than 50 and the Si / Al atomic ratio of 50 or more. The method of dealumination treatment is not particularly limited, but acid treatment is preferable. As the acid, nitric acid, hydrochloric acid, sulfuric acid or the like can be preferably used. Acid concentration,
Acid treatment conditions such as treatment temperature and treatment time are the target Si /
It is appropriately selected according to the Al atomic ratio. The Si / Al atomic ratio can be increased by increasing the treatment temperature and prolonging the treatment time. Further, in order to increase the mesopore volume and improve the catalytic activity, it is possible to use a calcined zeolite as a carrier before the dealumination treatment.

(Metal-based dehydrogenation catalyst) The catalyst used in the present invention can be prepared by supporting a metal-based dehydrogenation catalyst on a zeolite carrier having an appropriate Si / Al atomic ratio prepared in advance. As the metal-based dehydrogenation catalyst used at this time, a metal such as palladium, platinum, nickel, rhodium or ruthenium can be used. Of these metals, palladium and platinum are preferable because they show particularly excellent performance. As a method for preparing the metal-supported catalyst, a general method can be used and it is not particularly limited. As an example, the prepared carrier is dipped in an aqueous solution of a metal salt to impregnate and carry the metal, which is then dried in air at 130 ° C. and then 400 ° C.
The catalyst supporting the metal-based dehydrogenation catalyst can be obtained by firing at. The loading amount of the metal-based dehydrogenation catalyst on the zeolite carrier is not particularly limited, but is particularly 1 to 7 mass% from the viewpoint of conversion rate and selectivity.
Is preferred.

(Raw material THI) The raw material THI is
It can be obtained by isomerization of 5-vinylnorbornene, which is produced in a large amount as a by-product in the production of ethylidene norbornene and is also produced as a large amount of an intermediate in the production of 5-ethylidene norbornene.

(Dehydrogenation reaction) Using the above catalyst, THI
The dehydrogenation reaction for producing indane from is carried out as follows. The reaction type employs various industrial catalytic reaction technologies such as batch-type reaction in gas phase or liquid phase, atmospheric pressure gas phase flow reaction or liquid phase flow reaction using a fixed catalyst bed, and reaction using a catalyst fluidized bed. You can do it. The amount of catalyst used in the batch system and the conditions such as LHSV in the flow system can be appropriately selected. Although an atmospheric pressure fixed bed flow reactor is used in the examples, the present invention is not limited to this.

Other conditions can be appropriately selected according to the reaction type, but the reaction temperature is an important condition in the present invention. That is, in the conventional method, a reaction temperature of 400 ° C. or higher was required to obtain a preferable indane yield. However, when the reaction is carried out at a temperature of 400 ° C. or higher, the reaction product does not remain indane but forms indene or a thermal decomposition product, and these easily polymerized substances coat the catalyst surface and carbonize. In addition, it was unavoidable to reduce the catalytic activity in a short time. Further, when the reaction temperature is lowered to avoid the problem of coking, the reaction rate decreases, resulting in a low yield, or the reaction time becomes extremely long in order to obtain the desired indane yield. Was economically unsuitable industrially. In the method of the present invention, since the dehydrogenation catalyst has a high activity even at a low temperature, it is possible to efficiently carry out the reaction under a temperature condition where the catalytic activity is stable for a long time without causing the problem of coking. The preferable reaction temperature is 200 to 350 ° C. If the temperature is lower than 200 ° C, the reaction rate is slow, which is economically disadvantageous. Also, 350 ℃
When it exceeds, the production of indene and the decomposition of THI are promoted, which is not preferable. Particularly preferred reaction temperature is 250
C to 300C.

[0016]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. (Example 1) A USY zeolite catalyst manufactured by Catalysts & Chemicals Corporation having the same 12-membered oxygen ring pore structure as Y type zeolite was calcined in air at 650 ° C for 3 hours, and then 5.0 g was added to a volume of 300 m
1 round-bottomed flask was charged with 6 normal concentration nitric acid 10
0 ml was added, the mixture was heated to 100 ° C. in an oil bath, and dealumination treatment was performed for 20 hours. After treatment, wash with water,
After drying overnight, the adsorbed water was completely removed by baking at 500 ° C. for 3 hours in a muffle furnace. This treatment brought the Si / Al atomic ratio, which was initially 7.4, to 400. Next, using the USY zeolite thus modified as a carrier, 5% by mass as a metal dehydrogenation catalyst was prepared by the following method.
Supported platinum. That is, 9.12 g of modified USY zeolite was collected in a 200 ml evaporation dish, and 29.3 g of an aqueous solution of hexachloroplatinate (IV) acid having a concentration of 0.170 mol / l was added to this while stirring and stirred on a water bath. While being dried, platinum was impregnated and supported. After drying in air at 130 ° C for 1 hour, further in air at 300 ° C for 2 hours, 3
By firing at 50 ° C. for 3 hours and at 450 ° C. for 4 hours, a dehydrogenation catalyst for use in the present invention was obtained. The dehydrogenation reaction was carried out using a fixed bed flow reactor. For the reaction tube, use a tube with an inner diameter of 12.5 mm and a heating section length of 300 mm.
A catalyst layer of about 3 mm was provided in the center of the reaction tube heating section. The reaction tube was heated to 400 ° C. in an electric furnace and hydrogen gas was passed for 2 hours to pretreat the catalyst. When carrying out the reaction, the temperature was 275 ° C., and the THI of the reaction raw material was 1.5 per hour.
It was fed at a rate of g. The composition of the reaction product was determined by gas chromatography analysis. The result is 100% conversion,
Despite the extremely high indan selectivity of 95.8%, no indene was observed. In addition, no decomposition products were confirmed.

Example 2 The dehydrogenation reaction of THI was carried out in the same manner as in Example 1 except that a dehydrogenation catalyst supporting 5% by mass of palladium was used in place of platinum in Example 1. At the reaction temperature of 300 ° C., the conversion was 95.2%, and indene was not detected at all even though the selectivity of indane was as high as 85.8%. Further, the decomposition product selectivity was a low value of 3.4%.

[0018]

According to the present invention, by using a dehydrogenation catalyst in which a metal-based dehydrogenation catalyst is supported on a specific zeolite carrier, a high yield which cannot be achieved by the existing dehydrogenation catalyst under mild conditions is obtained. It becomes possible to manufacture indane.

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Claims (4)

[Claims] 1. Metal-based dehydration of 3a, 4, 7, 7a-tetrahydroindene on a zeolite carrier having a pore structure in which the Si / Al atomic ratio is 50 or more and the main cavity inlet has a 12-membered oxygen ring or more. A method for producing indane, comprising carrying out a dehydrogenation reaction in the presence of a dehydrogenation catalyst supporting an elementary catalyst. 2. The method for producing indane according to claim 1, wherein the zeolite carrier is an uncalcined or calcined zeolite that has been dealuminated. 3. The metal of the metal-based dehydrogenation catalyst is selected from the group consisting of platinum, palladium, nickel, rhodium and ruthenium.
Alternatively, the method for producing indane according to claim 2. 4. The method for producing indane according to claim 1, wherein the reaction temperature is 200 ° C. or higher and 350 ° C. or lower.