JP6005486B2 - Butene production method - Google Patents

Description

  The present invention relates to a process for producing butene from ethylene.

  Butene is obtained as a C4 fraction of naphtha cracker or FCC, and isobutene is used as a raw material for producing methyl methacrylate. Furthermore, in recent years, techniques for producing propylene and butadiene using n-butene as a raw material have been developed, and their uses are expanding.

  As a technique for producing n-butene, a technique for dimerizing ethylene using a nickel-based phosphine catalyst in a liquid phase is known in addition to the above method. However, since it is a high-pressure reaction, a great investment is required in terms of equipment and safety.

  On the other hand, techniques for producing olefins such as propylene from ethylene by a gas phase reaction have recently been studied.

  Patent Document 1 discloses that propylene can be selectively produced by performing a conversion reaction of ethylene in a gas phase using a catalyst in which a metal such as nickel is supported on a mesoporous material having a pore diameter of 2 to 10 nm. Yes. Depending on the reaction conditions, butene is the main product.

  Patent Document 2 discloses the production of olefins such as propylene from ethanol using a solid acid catalyst. However, the purpose is to improve propylene selectivity, and a method for selectively producing butene has not yet been developed.

  Patent Document 3 discloses a method for producing propylene from ethylene using an intermediate pore size zeolite having a pore size of 5 to 6.5 mm. However, the purpose is to improve propylene selectivity, and butene has not been produced selectively.

  Patent Document 4 discloses that n-butene is produced from ethylene by a first-stage reaction in order to produce propylene by a metathesis reaction between ethylene and n-butene. However, it does not propose a highly selective butene production method.

International Publication No. 2004/22228 JP 2007-191444 A International Publication No. 2009/31445 JP 2010-13366 A

  If butene can be produced with high selectivity from ethylene, it can be used as a new butene production route. Furthermore, when considering the use of bioethanol, raw materials other than petrochemical raw materials can be used by using ethylene obtained by dehydration of ethanol.

  An object of the present invention is to provide a method for producing butene that can produce butene with high selectivity from ethylene and that causes little decrease in catalytic activity even under reaction conditions in the presence of water.

The present invention uses a catalyst in which nickel is supported on a Y- type zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 250 or more and 500 or less, from ethylene at a reaction temperature of 200 ° C. or more and 600 ° C. or less in the gas phase. A method for producing butene.

  According to the method of the present invention, butene can be produced with high selectivity from ethylene. Furthermore, even under reaction conditions in the presence of water, there is little decrease in catalyst activity.

  First, the catalyst used in the present invention will be described.

  In the present invention, a catalyst in which nickel is supported on a faujasite type zeolite is used as a catalyst. The faujasite type zeolite is a skeleton structure type in accordance with the IUPAC recommendation, and is a zeolite having a FAU structure and a pore diameter of about 7 mm, and X-type zeolite and Y-type zeolite are known. In the present invention, zeolite having this pore size is suitable as a catalyst for butene synthesis by dimerization of ethylene, and it is considered that butene can be produced with high selectivity. In addition, it is considered that the reaction field becomes a hydrophobic atmosphere due to the hydrophobicity of the zeolite, and it is considered that the decrease in the catalytic activity can be suppressed even under the reaction conditions in the presence of water.

As the faujasite type zeolite used in the present invention, Y type zeolite is preferable. Further, a faujasite type zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 250 or more and 500 or less is preferable. The SiO ₂ / Al ₂ O ₃ molar ratio is more preferably 300 or more and 500 or less, and further preferably 400 or more and 500 or less. When the SiO ₂ / Al ₂ O ₃ molar ratio is 250 or more and 500 or less, the by-production of C5 or more heavy compounds can be suppressed. In particular, a Y-type zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio within the above range is considered more suitable for producing butene in terms of acid characteristics and hydrophobicity. The SiO ₂ / Al ₂ O ₃ molar ratio is a value measured by the ICP emission spectrum method.

  A commercially available Y-type zeolite can be used. However, it is preferable to use a zeolite that has been dealuminated by steam treatment or acid treatment, called ultra-stabilized Y-type zeolite (USY). Among these, a zeolite having a proton type ion exchange site is preferable. Ultra-stabilized Y-type zeolite having proton exchange ion sites may be described as “H-USY zeolite”.

  The method for supporting nickel on the faujasite type zeolite is not particularly limited. For example, nickel can be supported by an impregnation method, a vapor deposition method, or the like. As the nickel raw material, a nickel salt can be used. The kind of the nickel salt is not particularly limited, but it is preferable to use a nitrate that can be decomposed by firing in air.

  The amount of nickel supported is not particularly limited, but from the viewpoint of ethylene conversion and butene selectivity, the amount of nickel supported is 0.1 parts by mass or more and 15 parts by mass with respect to 100 parts by mass of faujasite-type zeolite serving as a support. The amount is preferably not more than part by mass, and more preferably not less than 0.5 part by mass and not more than 10 parts by mass. The supported amount is a value calculated from the charged amount of nickel raw material.

  The nickel-supported faujasite type zeolite can be used after being calcined in air. The firing temperature is preferably 300 ° C to 900 ° C. The firing time is preferably 1 hour to 10 hours. By being within the range of the firing time and firing temperature, the supported nickel salt can be sufficiently decomposed.

  The catalyst used in the present invention can be used in various shapes such as powder, granule, pellet, and honeycomb.

  Next, the butene manufacturing method according to the present invention will be described.

  In the present invention, the ethylene conversion reaction is carried out in the gas phase. For example, it is carried out by introducing an ethylene-containing gas into the reactor filled with the catalyst.

  Although the reaction mode of ethylene in the present invention is not particularly limited, a reactor such as a fixed bed or a fluidized bed can be used.

  In the present invention, the concentration of ethylene supplied to the reactor is not particularly limited. The ethylene raw material may be diluted with nitrogen or steam.

  The reaction temperature in the present invention is preferably from 200 ° C. to 600 ° C., more preferably from 250 ° C. to 350 ° C. If the reaction temperature is 200 ° C. or higher, sufficient catalytic activity can be obtained. Moreover, if reaction temperature is 600 degrees C or less, by-products, such as alkane and a C5 or more heavy compound, can be suppressed.

  In the present invention, the contact time between the raw material gas and the catalyst is preferably 0.01 g-catalyst / second / ml-raw material gas or more and 10 g-catalyst / second / ml-raw material gas or less, preferably 0.1 g-catalyst / second / ml. -More than source gas, 5g-catalyst * second / ml-source gas or less is more preferable. When the contact time is 0.01 g-catalyst · second / ml-feed gas or more, a sufficient ethylene conversion rate can be obtained. Further, when the contact time is 10 g-catalyst · second / ml-source gas or less, by-products such as alkanes and heavy compounds of C5 or higher can be suppressed.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

[Example 1]
(Catalyst preparation)
In 20 g of H-USY zeolite (SiO ₂ / Al ₂ O ₃ molar ratio = 470, trade name HSZ-390HUA, manufactured by Tosoh Corporation), 0.99 g of nickel nitrate hexahydrate was dissolved in 50 ml of ion-exchanged water. The solution was added and stirred for 1 hour. Thereafter, the mixed solution was evaporated to dryness and baked at 450 ° C. in air for 4 hours. Thus, a nickel-supported H-USY zeolite catalyst (Ni / H-USY) was prepared. The amount of nickel supported on the catalyst was 1.0 part by mass with respect to 100 parts by mass of the carrier.

(Reaction evaluation)
The following operation was performed using a flow reactor. A quartz glass reaction tube was filled with 1.0 g of the catalyst, and pretreated at 450 ° C. for 2 hours under a helium flow. After the temperature was lowered to each reaction temperature, an ethylene conversion reaction was carried out by supplying a mixed gas of ethylene and helium (ethylene: helium = 4: 1 (volume ratio)) at a rate of 120 ml / min. Sampling was performed 60 minutes after the start of ethylene supply, and the product was analyzed by gas chromatography. The results are shown in Table 1. The butene selectivity represents the total selectivity of 1-butene and 2-butene.

[Example 2]
Catalyst preparation and reaction evaluation were performed in the same manner as in Example 1 except that H-USY zeolite (SiO ₂ / Al ₂ O ₃ molar ratio = 270, manufactured by JGC Catalysts & Chemicals Co., Ltd.) was used. The results are shown in Table 1.

[ Reference Example 1 ]
Catalyst preparation and reaction evaluation were performed in the same manner as in Example 1 except that H-USY zeolite (SiO ₂ / Al ₂ O ₃ molar ratio = 70, manufactured by JGC Catalysts & Chemicals Co., Ltd.) was used. The results are shown in Table 1.

[Comparative Example 1]
Catalyst preparation and reaction in the same manner as in Example 1 except that H-ZSM-5 type zeolite (SiO ₂ / Al ₂ O ₃ molar ratio = 485, manufactured by Nippon Chemical Industry Co., Ltd.), which is an MFI type zeolite, was used. Evaluation was performed. The results are shown in Table 1.

  From Table 1, it can be seen that butene can be obtained with good selectivity by carrying out an ethylene conversion reaction using nickel-supported faujasite type zeolite.

[Example 4]
(Water addition test)
In the reaction evaluation at a reaction temperature of 300 ° C. in Example 2, a mixed gas of ethylene, water and helium (ethylene: water: helium = 3: 1) instead of a mixed gas of ethylene and helium after 2 hours from the start of the reaction. : 1 (volume ratio)) was fed at a rate of 120 ml / min. This confirmed the influence of water. The ethylene conversion rate after 2 hours from the start of water addition was 12.4%.

[Comparative Example 2]
A catalyst was prepared in the same manner as in Example 1 except that silica-alumina (Catalyst Society Reference Catalyst JRC-SAL-2, Al ₂ O ₃ 13.8% by mass) was used instead of H-USY zeolite. Thereafter, a water addition test was conducted in the same manner as in Example 4 except that the catalyst was used. The ethylene conversion before water addition was 38.0% and the butene selectivity was 57.9%, but the ethylene conversion after 2 hours from the start of water addition was 0%.

  From the results of Example 4 and Comparative Example 2, it can be seen that when the conversion reaction of ethylene is carried out using nickel-supported faujasite-type zeolite, the catalytic activity is hardly lowered even in the presence of water.

Claims (1)

Producing butene from ethylene at a reaction temperature of 200 ° C. or more and 600 ° C. or less in a gas phase using a catalyst in which nickel is supported on a Y- type zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 250 or more and 500 or less. Method.