JPH0453851B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for selectively producing ethylbenzene, which is useful as a raw material for styrene. (Prior art) Regarding the method of ethylating benzene in the gas phase, a method using crystalline aluminosilicate ZSM-5 as a catalyst developed by Mobil Corporation in recent years (see Japanese Patent Publication No. 56-44050) is known. .
However, if ZSM-5 is used as a catalyst as it is, many by-products such as toluene and ethyltoluene are generated.
57688), and in fact, a process known as the Mobile Bazier process has been proposed using these catalysts. (Problem to be solved by the invention) However, ZSM treated with phosphorus oxide
The method using -5 does have a high selectivity to ethylbenzene and diethylbenzene, reaching 97% in some cases, but it is difficult to achieve an extremely high selectivity of 98% or more, and there is also the problem of low activity. It was hot. Furthermore, this reaction causes precipitation of carbonaceous matter on the catalyst during the reaction, which is accompanied by a decrease in activity over time. In order to prevent this, it is possible to coexist with hydrogen, but if treated with phosphorus oxide,
In the case of ZSM-5, when hydrogen coexists, toluene,
It was found that there were many by-products such as ethyltoluene, which caused a problem in which the selectivity decreased. (Means for solving the problem) The present inventors aimed to develop a catalyst that has high activity with a selectivity to ethylbenzene and diethylbenzene of 98% or more, and that does not lose selectivity even in the coexistence of hydrogen. As a result of extensive studies, the inventors discovered that when a crystalline aluminosilicate having the diffraction pattern shown in Table 1 in an X-ray diffraction diagram is used as a catalyst, results satisfying the objective can be obtained, and the present invention has been completed. .

[Table] X-ray diffraction analysis is performed using CuKα radiation. However, the relative intensity of either the 8.7±0.2 or 8.9±0.2 diffraction lines is set to 100. That is, the present invention is characterized in that when benzene is reacted with ethylene in a gas phase in the presence of hydrogen, a crystalline aluminosilicate having a diffraction pattern shown in Table 1 in an X-ray diffraction diagram is used as a catalyst. The present invention provides a method for ethylating. The crystalline aluminosilicate having the diffraction pattern shown in Table 1 used in the present invention is AZ
It is a crystalline aluminosilicate with a unique crystal structure called JP-A-1 (see Japanese Patent Application Laid-Open No. 59-128210). The reaction temperature in the present invention is in the range of 200 to 600°C, preferably 300 to 500°C. Further, the pressure may be normal pressure or increased pressure, and a preferable range is normal pressure to 20 kg/cm ² . The present invention is carried out by a gas phase flow method, in which the benzene/ethylene molar ratio is in the range of 1 to 20, preferably 2 to 10, and the hydrogen/ethylene molar ratio is in the range of 0.5 to 20.
20, preferably in the range of 1 to 10. (Effects of the Invention) According to the method of the present invention, compared to the conventional method using ZSM-5 treated with phosphorus oxide as a catalyst, a high yield can be achieved in the coexistence of hydrogen, and an extremely high selectivity can be achieved. Ethylbenzene and diethylbenzene can be obtained. This becomes extremely advantageous in industrial implementation. (Example) Example 1 1,8-diamino-4-aminomethyloctane
100g, aluminum sulfate (Al ₂ (SO ₄ ) ₃・18H ₂ O)
Dissolve 5g of sodium hydroxide in 150g of water,
Furthermore, 200 g of isilica sol (30% SiO ₂ ) was added to obtain a homogeneous solution. Add to this solution while stirring.
30 g of 20% sulfuric acid was added dropwise to obtain a homogeneous gel. Furthermore, put this gel in a homogenizer,
Mixed for 10 minutes at 10000 rpm. This gel was stored at 180℃ and 45℃ in a Teflon-lined stainless steel pressure container.
The mixture was allowed to stand for a period of time for crystallization. After filtering and washing the obtained product, it was heated to 120℃.
The mixture was dried at 500°C for 6 hours and then fired at 500°C for 6 hours. The X-ray diffraction pattern of this product is shown in the drawing.
From this diffraction pattern, this product is AZ-1
was identified. Furthermore, the silica/alumina molar ratio determined from fluorescent X-ray analysis was 80. Using this crystalline aluminosilicate AZ-1 as a catalyst, benzene and ethylene were reacted. The experimental conditions were: benzene/ethylene/H ₂ molar ratio = 4/1/4, WHSV (benzene standard) =
The reaction time was 4.0 hr ^-1 , the reaction temperature was 400°C, and the pressure was 3.0 Kg/cm ² . Table 2 shows the results at 2 hours, 6 hours, and 20 hours after the start of the reaction.

[Table] Example 2 Using the catalyst obtained in Example 1, benzene/
Ethylene/ _H2 molar ratio=5/1/4, WHSV=
The reaction was carried out at a reaction time of 4.0 hr ^-1 , a reaction temperature of 430°C, and a pressure of 5.0 kg/cm ² . Table 3 shows the results at 3 hours, 40 hours, and 120 hours after the start of the reaction.

【table】

[Table] Example 3 1,8-diamino-4-aminomethyloctane
2,000 g of aluminum sulfate, 150 g of aluminum sulfate, and 150 g of sodium hydroxide were dissolved in 5,000 g of water, and 4,000 g of silica sol (30% SiO ₂ ) was added to obtain a homogeneous liquid. Add 500 g of 20% sulfuric acid to this solution while stirring.
was added to obtain a homogeneous gel. Furthermore, this gel was placed in a homogenizer and mixed at 10,000 rpm for 20 minutes. This gel was crystallized by standing at 165° C. for 60 hours in a Teflon-lined stainless steel pressure container. After filtering and washing the obtained product, it was heated to 120℃.
The mixture was dried at 500°C for 6 hours and then fired at 500°C for 6 hours. Based on the X-ray diffraction pattern of this product, this product was identified as AZ-1. Furthermore, the silica/alumina molar ratio determined from fluorescent X-ray analysis was 80. Using this AZ-1 as a catalyst, a reaction between benzene and ethylene was carried out. The experimental conditions were: benzene/ethylene H ₂ mo ratio = 3/1/2, WHSV = 5.2 hr ^-1 , reaction temperature 420°C, and pressure = 4.0 Kg/cm ² . Table 4 shows the results 3 hours and 25 hours after the start of the reaction.

【table】

[Table] Example 4 Using the catalyst obtained in Example 3, benzene/ethylene/H ₂ molar ratio = 6/1/3, WHSV =
The reaction was carried out at a reaction time of 6.0 hr ^-1 , a reaction temperature of 440°C, and a pressure of 4.0 Kg/cm ² . Table 5 shows the results at 2 hours, 30 hours, and 150 hours after the start of the reaction.

[Table] Comparative example Dissolve 5 g of aluminum sulfate and 10 g of tetrapropylammonium bromide in 550 g of water, and add Q brand silicate aqueous solution (Na ₂ O = 8.9% by weight,
150 g of SiO ₂ =28.9% by weight, H ₂ O = 62.2% by weight) was added and stirred to obtain a homogeneous gel. 50 g of 20% H ₂ SO ₄ was added dropwise to this gel while stirring to promote gelation. This gel was placed in a Teflon-lined autoclave and crystallized with stirring at 150°C for 20 hours. After over-washing the obtained product, it was dried at 120°C for 3 hours and calcined in air at 500°C for 4 hours. The X-ray diffraction pattern of this product is ZSM-5
It matched the diffraction pattern of Furthermore, the silica/alumina molar ratio determined by fluorescent X-ray diffraction was 50. This ZSM-5 was ion-exchanged with a 1N ammonium chloride aqueous solution at 60℃ for 24 hours, filtered, washed, dried at 120℃ for 6 hours, and air-calcined at 500℃ for 5 hours to obtain H-ZSM-5. Obtained. 10g of the obtained H-ZSM-5 was placed in a flask.
Trimethyl phosphorite 4 in n-octane 50 c.c.
cc was added to the solution. The mixture was heated at reflux temperature for 80 hours with a gradual flow of nitrogen.
Thereafter, this mixture was evaporated to dryness, the resulting solid was calcined with pentane, and then dried at 120°C for 10 hours.
It was baked at 500°C for 3 hours. The amount of phosphoric oxide supported in the obtained product was 8.2% by weight. Using this phosphorus-containing H-ZSM-5 as a catalyst,
Benzene/ethylene/H ₂ =4/1/4, WHSV
The reaction time was 4.0 hr ^-1 , the reaction temperature was 400°C, and the pressure was 3.0 Kg/cm ² . Table 6 shows the results 6 hours after the start of the reaction.

【table】

【table】

【table】 [Brief explanation of the drawing]

The drawing shows the X-ray diffraction pattern of the crystalline aluminosilicate AZ-1 obtained in Example 1.

Claims (1)

[Claims] 1. A method for reacting benzene with ethylene in the gas phase in the presence of hydrogen, using as a catalyst a crystalline aluminosilicate having a diffraction pattern shown in the table below in an X-ray diffraction diagram. Ethylation method. [Table] X-ray diffraction analysis is performed using CuKα radiation. However, either the diffraction line of 8.7± or 8.9±0.20.2 is taken as a relative intensity of 100.