KR101589140B1 - Ordered mesoporous-silica based catalysts for the production of 1,3-butadiene and production method of 1,3-butadiene using thereof - Google Patents

Abstract

The present invention relates to a catalyst for producing 1,3-butadiene having a transition metal compound supported on regular mesoporous silica and a process for producing 1,3-butadiene using the same. More specifically, The selectivity can be improved by specifying the kind and content of the transition metal oxide and the synthesis yield of 1,3-butadiene can be increased by the high dispersion activity point due to the high surface area, Since it has a pore structure, diffusion and mass transfer of reactants and products are easy, and since the active sites can be uniformly participated in the reaction uniformly without being biased, deactivation phenomenon is observed compared to existing silica catalysts in which fine pores and mesopores coexist The catalyst life is remarkably improved as compared with the conventional silica-based catalyst, so that the regeneration cycle becomes longer, It is possible to improve, it can be usefully employed in the preparation of 1,3-butadiene.

Description

[0001] The present invention relates to a mesoporous silica-based catalyst for preparing 1,3-butadiene from ethanol, and to a process for producing 1,3-butadiene using the meso-porous silica catalyst, 3-butadiene using < RTI ID =

The present invention relates to a catalyst for preparing 1,3-butadiene having a transition metal compound supported on regular mesoporous silica and a process for producing 1,3-butadiene using the same.

Recently, there have been many studies to develop renewable energy resources using biomass as the high oil prices and depletion of petroleum resources are intensifying. Biomass consumes carbon dioxide, which is a greenhouse gas during its lifecycle, And the total amount of carbon dioxide generated by the fuel cell is reduced. In particular, the technology to manufacture high value-added basic chemicals based on ethanol, which can be easily obtained in large quantities from alternative petroleum resources, is an innovative technology that can change the paradigm of the petrochemical industry, , And a representative example thereof is 1,3-butadiene.

1,3-butadiene has been a major source of synthetic rubber and has seen rapid increases in demand during World War I, and since then has seen steady demand growth. Generally, 1,3-butadiene is inexpensively obtained as a by-product in the process of producing ethylene and propylene in a naphtha cracking process (Non-Patent Document 1). However, due to recent high oil prices, the price of naphtha, which is the main raw material of 1,3-butadiene, has risen, and thus the price of 1,3-butadiene has risen sharply, .

In particular, demand for synthetic rubber has risen sharply in recent years due to rapid economic growth in China, and the supply of 1,3-butadiene in the Asian market is very poor. As a result, the price of 1,3-butadiene in Asia is higher than other regions, and the burden of increasing the cost of synthetic rubber is increasing. Therefore, 1,3- There is a great demand for the expansion of the butadiene production plant and the development of the production process for 1,3-butadiene production cost reduction.

The synthesis of 1,3-butadiene is possible in a variety of ways. The first synthesis was made from ethanol by Lebedev of Russia in 1910, and then produced from butene, butane and naphthene with rising ethanol prices. As of 1944, butenes accounted for 38%, 35% for ethanol, 11.4% for butane, and 15.1% for naphtha as raw materials for 1,3-butadiene, but are currently not produced from ethanol and over 95% It is produced from the decomposition process and part of it is produced through the dehydrogenation process of butane and butene. However, due to the recent rapid rise in naphtha prices due to high oil prices, the 1,3-butadiene production process is expected to increase through the dehydration process of butane and butene, which are similar petroleum products, rather than the existing naphtha cracking process.

Conventionally, Patent Document 1 - 5 discloses a method for producing 1,3-butadiene from C ₄ mixture of butane or butene or a mixture thereof. However, since it is also necessary to use petroleum oil obtained from naphtha cracking, difficulties in supply and demand are similar. As a result, technology for directly synthesizing butadiene from ethanol, which is a substitute for petroleum, can be an alternative solution to such a problem. I was wrong.

In the process of producing 1,3-butadiene from ethanol, various methods for economically synthesizing ethanol from petroleum substitute raw materials such as coal and biomass have been studied, and interest is continuously increasing. In particular, the price of bioethanol is very low compared to the conventional ethanol synthesis process, so it is expected that the production process of 1,3-butadiene using bioethanol will be competitive in the future. In addition, a lot of research is underway on the production process for production of competitive ethanol by producing synthetic gas using chemical coal and chemical conversion process in China, where coal reserves are abundant. The production process of 1,3-butadiene by the above-mentioned step of synthesizing the competitive ethanol is expected to further enhance the competitiveness of the process. Therefore, it is considered that the process for preparing 1,3-butadiene from ethanol is very important.

The technology for producing 1,3-butadiene from ethanol is largely divided into a one-step process (Lebedev process) for directly producing butadiene from ethanol and a two-step process (a two-step process) in which ethanol is appropriately mixed with acetaldehyde. step process, American process). The overall reaction formula is a reaction through dehydrogenation and dehydration reaction as shown in the following equations (1) and (2). The former is a method for producing butadiene by a simultaneous dehydrogenation and dehydration in a reactor, Acetaldehyde is separately prepared and mixed with ethanol at a proper ratio.

C ₂ H ₆ OH -> CH ₃ CHO + H ₂ (1)

CH ₃ CH ₂ OH + CH ₃ CHO CH ₂ = CH-CH = CH ₂ + 2 H ₂ O (2)

That is, the method of directly producing butadiene from the former ethanol is simple in view of the process but the yield is very low, and MgO-SiO ₂ and ZnO-Al ₂ O ₃ systems are mainly used as catalysts. On the other hand, the latter requires the production of acetaldehyde using a catalyst suitable for dehydrogenation of Cu-CrO _3, so that the process is complicated, but the yield of 1,3-butadiene is high.

Silica-based catalysts on which transition metal oxides such as tantalum oxide and zirconium oxide are supported, which are typical catalysts for producing 1,3-butadiene from ethanol and acetaldehyde, and particularly silica-based catalysts on which tantalum oxide is supported have been developed in the 1940s, However, the 1,3-butadiene selectivity limited to about 64% is not overcome, and the catalyst activity regeneration cycle is about 4 to 5 days. , And after the 1950 's commercial competitiveness has been lost and commercial processes have disappeared.

Therefore, silica has been recently developed and silica having various properties has been developed. Therefore, if addition of catalyst life and 1,3-butadiene selectivity is further improved through optimization of silica characteristics, It would be possible to develop 1,3-butadiene manufacturing process from ethanol.

Conventionally, Patent Document 6 discloses a catalyst in which a transition metal oxide is deposited on a nanosilica. However, since the nanosilica-based catalyst has a high selectivity and improved catalyst life than that of the conventional silica gel carrier, the catalyst is inactivated due to carbon deposition by micropore, .

Therefore, there is a need to develop a catalyst capable of improving the catalyst inactivation by the carbon deposition to improve the lifetime of the catalyst, thereby increasing the catalyst regeneration cycle and greatly increasing the process efficiency.

Accordingly, the present inventors have been interested in a catalyst having excellent selectivity and yield and capable of reducing the activity degradation due to pore clogging, and have found that a catalyst having transition metal oxide on regular mesosilica has a high surface area The yield of 1,3-butadiene is increased by the high dispersing activity point and the regular mesoporous structure is formed. Therefore, diffusion and mass transfer of reactants and products are easy and not biased, , It is confirmed that the catalytic lifetime is significantly improved as compared with the conventional silica catalyst, since the activity is lowered than that of the conventional silica catalyst in which fine pores and mesopores coexist.

Patent Document 1: Korean Patent Publication No. 2012-0009687 Patent Document 2: Korean Patent Publication No. 2011-0130130 Patent Document 3: Korean Patent Publication No. 2011-0106181 Patent Document 4: Korean Patent Publication No. 2010-0042935 Patent Document 5: Korean Patent Publication No. 2009-0103424 Patent Document 6: Korean Patent No. 1152768

 Non-Patent Document 1: Chemico-Biological Interaction 166 (2007)

An object of the present invention is to provide a catalyst for the production of 1,3-butadiene with improved selectivity, synthesis yield and catalyst life, and a process for producing the catalyst.

Also, an object of the present invention is to provide a process for producing 1,3-butadiene from ethanol or a mixture of ethanol and acetaldehyde using the catalyst for 1,3-butadiene production.

In order to achieve the above object,

A catalyst for producing 1,3-butadiene having a transition metal oxide supported on ordered mesoporous silica (OMS) is provided.

In addition,

Preparing a regular mesoporous silica (step 1);

Impregnating the regular mesoporous silica of step 1 with the transition metal oxide (step 2).

Further,

A method for producing 1,3-butadiene, which comprises reacting ethanol or a mixture of ethanol and acetaldehyde using a catalyst, wherein the catalyst is the 1,3-butadiene catalyst of the present invention, 3-butadiene.

The catalyst for preparing 1,3-butadiene carrying the transition metal oxide on the regular mesoporous silica according to the present invention can improve the selectivity by optimizing the kind and characteristics of the silica and specifying the kind and content of the transition metal oxide , The high synthesis rate of 1,3-butadiene due to the high surface area can be increased, and the regular mesoporous structure can facilitate diffusion and mass transfer of reactants and products, Since all the active sites can participate in the uniform reaction uniformly, the catalyst activity is significantly lowered than that of the existing silica catalysts in which micropores and mesopores coexist, so that the catalyst lifetime is significantly improved compared to the silica catalysts. Since the effect of increasing the operation efficiency can be obtained, it can be usefully used in the production of 1,3-butadiene .

1 is a graph showing pore size distributions of regular mesoporous silica-based catalysts of Examples 1 to 10 of the present invention and conventional silica-based catalysts of Comparative Examples 1 to 3.

Hereinafter, the present invention will be described in detail.

The present invention provides a catalyst for the production of 1,3-butadiene carrying a transition metal oxide on ordered mesoporous silica (OMS).

In particular, the regular mesoporous silica according to the present invention serves as a carrier in the catalyst. Mesoporous silica not only has a high surface area but also has shaped mesopores, which leads to an increase in the yield of 1,3-butadiene, but also to a reaction in large, homogeneous mesoporous pores that are free of reaction and product migration It is advantageous in that the activity drop due to the micropore clogging of the catalyst can be reduced and the reaction participation efficiency of the active sites can be greatly increased compared with other carriers having irregularly distributed mesopores and wide irregular mesopores.

In addition, the regular mesoporous silica according to the present invention is not distributed in the fine pores in the particles but distributed on the surface of the mesoporous silica particles, and diffusion and mass transfer of the reactants and products are accelerated, The decrease in activity is greatly improved. The surface area and the pore size of the regular mesoporous silica carrier can be controlled by the synthesis method, but they are not linearly related to each other, so there is an optimum surface area and pore structure for each type of regular mesoporous silica.

The regular mesoporous silica according to the present invention may be one that is commonly used in the art, preferably a KIT (Korea Advanced Institute of Science and Technology), a Mesoporous Molecular Sieve (MMS), a Mobile Composition of Matter ), SBA (Santa Barbara), or TUD (Technische Universiteit Delft) series.

Furthermore, the regular mesoporous silica according to the present invention preferably has an average pore size of 1 to 50 nm, more preferably an average pore size of 2 to 10 nm. Most preferably, the pore size is in the range of 3 to 8 nm. When the mean pore size of the silica is less than 1 nm, the structural stability of the catalyst decreases, the reaction activity decreases rapidly in the region of the fine pores, and it is difficult to handle in the heterogeneous catalyst process. If it exceeds 50 nm, there is a problem that the surface area becomes small and the activity of the catalyst is deteriorated.

The regular mesoporous silica according to the present invention preferably has a surface area of 100 to 1500 m ² / g, more preferably 200 to 1000 m ² / g. And most preferably from 550 to 1000 m ² / g. When the surface area of the silica is less than 100 m ² / g, there is a disadvantage in that the dispersibility of the catalyst is decreased and the catalytic activity is lowered. When the surface area is more than 1500 m ² / g, the structural stability of the catalyst itself is poor.

More specifically, the regular mesoporous silica may have a pore size of 3 to 8 nm and a surface area of 550 to 1000 m ² / g in the following range. Specifically, it is preferable to use a material having a surface area of 780 m ² / g or more and 1000 m ² / g or less in the range of the pore size of 3 nm or more and 5 nm or less. In the range where the pore size is more than 5 nm but not more than 8 nm, it is preferable to use those having a surface area of not less than 550 m ² / g and not more than 780 m ² / g.

Furthermore, the transition metal oxide according to the present invention is preferably a Group III, IV, or V transition metal oxide. The kind of the group III, IV, or V transition metal oxide is not limited, but preferably at least one transition metal oxide selected from yttrium oxide, lanthanum oxide, hafnium oxide, zirconium oxide, tantalum oxide, It is more preferable to use tantalum oxide. The transition metal oxide means a compound in which a transition metal and oxygen are bonded, and the oxidation number of the transition metal is not limited. Preferably, Y ₂ O ₃ , HfO ₂ , ZrO ₂ , Ta ₂ O _5, or Nb ₂ O ₅ is used .

The transition metal oxide of the present invention is preferably contained in an amount of 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight based on 100 parts by weight of the total catalyst. When the transition metal oxide is contained in an amount of less than 0.1 part by weight based on 100 parts by weight of the total catalyst, the activity of the catalyst is too low to be used as a catalyst. When the transition metal oxide is contained in an amount exceeding 10 parts by weight, The increase in activity is lowered, which is not desirable due to the low economic efficiency.

As a result of the calculation of catalyst conversion and 1,3-butadiene selectivity for the catalyst of the present invention, the regular mesoporous silica-based catalyst of the present invention was found to have an irregular pore silica catalyst Butadiene is higher than that of the catalyst, the catalyst performance and 1,3-butadiene synthesis yield are high.

The catalyst conversion rate and the 1,3-butadiene selectivity after 50 hours of the reaction of the catalyst of the present invention were calculated according to Experimental Example 1 of the present invention. As a result, The rate at which the selectivity of butadiene is reduced is significantly lower than that of the conventional irregular pore silica catalyst, and it is confirmed that the lifetime of the catalyst is also improved.

Further, referring to Experimental Example 2 of the present invention, in order to evaluate the regenerating ability of the catalyst of the present invention, the deactivated catalyst was regenerated for 5 hours and then used in the reaction of ethanol and acetaldehyde to obtain a catalyst conversion ratio and 1,3- As a result of the selectivity calculation, not only the high 1,3-butadiene selectivity is shown before the regeneration, but also the reaction activity and the 1,3-butadiene selectivity are restored stably even after regeneration of the catalyst. The selectivity of 3-butadiene is increased.

From the above experimental results, it can be seen that the catalyst having the transition metal oxide supported on the regular mesoporous silica of the present invention has excellent selectivity and 1,3-butadiene synthesis yield, and the catalytic activity deterioration phenomenon is improved, But also the regenerating ability is improved as compared with the conventional silica-based catalyst, so that it can be usefully used for the production of 1,3-butadiene.

Further, the present invention provides a method of preparing a mesoporous silica comprising the steps of: preparing a regular mesoporous silica (step 1); And

Impregnating the regular mesoporous silica of step 1 with the transition metal oxide (step 2).

Hereinafter, the above-described method of preparing a catalyst for 1,3-butadiene production will be described in more detail.

First, in the method for preparing a catalyst for 1,3-butadiene according to the present invention, step 1 is a step of preparing regular mesoporous silica.

Specifically, the regular mesoporous silica according to the present invention of step 1 according to the present invention may be one which is commonly used in the art, preferably KIT (Korea Advanced Institute of Science and Technology), MMS (Mesoporous Molecular Sieve, MCM (Mobile Composition of Matter), SBA (Santa Barbara) or TUD (Technische Universiteit Delft) series.

The regular mesoporous silica of step 1 according to the present invention preferably has an average pore size of 1 to 50 nm, more preferably an average pore size of 2 to 10 nm . Most preferably, the pore size is in the range of 3 to 8 nm.

Further, the regular mesoporous silica of step 1 according to the present invention preferably has a surface area of 100 to 1500 m ² / g, more preferably 200 to 1000 m ² / g . And most preferably from 550 to 1000 m ² / g.

More specifically, the regular mesoporous silica may have a pore size of 3 to 8 nm and a surface area of 550 to 1000 m ² / g in the following range. Specifically, it is preferable to use a material having a surface area of 780 m ² / g or more and 1000 m ² / g or less in the range of the pore size of 3 nm or more and 5 nm or less. In the range where the pore size is more than 5 nm but not more than 8 nm, it is preferable to use those having a surface area of not less than 550 m ² / g and not more than 780 m ² / g.

The transition metal oxide of step 2 according to the present invention is preferably a group III, IV, or V transition metal oxide. The kind of the group III, IV, or V transition metal oxide is not limited, but preferably at least one transition metal oxide selected from yttrium oxide, lanthanum oxide, hafnium oxide, zirconium oxide, tantalum oxide, It is more preferable to use tantalum oxide.

Furthermore, the content of the transition metal oxide in the step 2 according to the present invention is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight based on 100 parts by weight of the total catalyst.

The method of impregnating the regular mesoporous silica of step 2 according to the present invention with the transition metal oxide is a method generally used in the art, and is not particularly limited. Preferably, it can be impregnated by incipient wetness impregnation or excess impregnation, and the excess impregnation method is more preferable because it can increase the degree of dispersion of the active metal.

Further, the present invention provides a process for producing 1,3-butadiene comprising reacting ethanol or a mixture of ethanol and acetaldehyde using a catalyst,

The present invention provides a process for producing 1,3-butadiene, wherein the catalyst is the 1,3-butadiene catalyst of the present invention.

Hereinafter, the 1,3-butadiene production method of the present invention will be described in detail.

The synthesis of 1,3-butadiene according to the present invention is carried out by introducing a mixture of ethanol or ethanol and acetaldehyde diluted with nitrogen in a fixed-bed reactor in which 1,3-butadiene is present, can do.

The reaction of the ethanol or the mixture of ethanol and acetaldehyde according to the present invention is preferably carried out at a temperature of 300 ° C to 400 ° C, more preferably 330 ° C to 370 ° C. When the reaction temperature is lower than 300 ° C, the reaction activity is too low. When the reaction temperature is higher than 400 ° C, the selectivity of butadiene is lowered.

Further, the reaction of the ethanol or the mixture of ethanol with acetaldehyde according to the present invention may be carried out in the range of 0.1 hr ^-1 to 10.0 hr ^-1 Is preferably performed in a liquid hourly space velocity, more preferably in a range of 0.5 hr ^-1 to 5.0 hr ^-1 . If the space velocity is less than 0.1 hr <" ¹ >, the atmosphere is likely to cause a cracking reaction in which the products are transferred to the secondary reaction due to low residence time in the catalyst layer, so that the desired selectivity is lowered, If the space velocity exceeds 10.0 hr < ^{-1 &} gt ;, the residence time is too short, so that a component having a low molecular weight such as methane tends to be generated and the reaction performance becomes too low.

The molar ratio of ethanol to acetaldehyde in the mixture is preferably 1: 0.001 to 1: 0.7, more preferably 1: 0.2 to 1: 0.5. When the molar ratio of acetaldehyde to ethanol is less than 0.001, the condensation reaction with ethanol and acetaldehyde does not occur. When the molar ratio of acetaldehyde to ethanol is more than 0.7, acetic acid or the like is produced by dehydration reaction of acetaldehyde Since side reactions are easily caused, there is a problem that the selectivity of 1,3-butadiene is lowered when the amount is outside the above range.

Hereinafter, the present invention will be described in detail with reference to the following examples.

However, the following examples are illustrative of the present invention and are not intended to be limiting.

Example 1 SBA-15 Catalyst Supported with Tantalum Oxide-1

Regular mesoporous silica (OMS) SBA-15 is described by M. Choi, W. Heo, F. Kleitz, and R. Ryoo, Chem. Commun. (2003) 1340-1341. To the solution obtained by mixing 114 g of distilled water, 37% hydrochloric acid and 3.5 g of hydrochloric acid, 6.0 g of Pluronic, P123, which is a triplet polymer, was added, and the mixture was stirred at 35 ° C until it became a homogeneous mixture Strongly stirred. 13.0 g of tetraethyl orthosilicate (TEOS) was added to the homogeneously mixed solution, followed by vigorous stirring for 24 hours at a temperature of 35 ° C. The mixture was aged at a temperature of 35 캜 for 24 hours. After filtration, the dried mesoporous silica (OMS), SBA-15 was prepared by drying at 100 ° C. for 12 hours and then heating at a rate of 1 ° C./min and calcining at 550 ° C. for 6 hours.

Next, tantalum oxide (Ta ₂ O ₅ ) was supported on the SBA-15 silica by excess impregnation using Aldrich's tantalum chloride (TaCl ₅ ). The content of tantalum oxide was adjusted to be 2 parts by weight per 100 parts by weight of the total catalyst. The prepared sample was dried at 120 ° C. for 10 hours and then calcined at 500 ° C. for 5 hours to prepare an SBA-15 catalyst carrying the tantalum oxide of Example 1.

Example 2 SBA-15 catalyst carrying tantalum oxide-2

When preparing SBA-15, SBA-15 catalyst carrying the tantalum oxide of Example 2 was prepared in the same manner as in Example 1 except that the catalyst was aged at 60 ° C.

<Example 3> SBA-15 catalyst carrying tantalum oxide-3

SBA-15 catalyst was prepared by carrying out the same procedure as in Example 1 except that the mixed solution was aged at 80 占 폚.

<Example 4> SBA-15 catalyst carrying tantalum oxide-4

SBA-15 catalyst was prepared in the same manner as in Example 1, except that the mixed solution was aged at 100 ° C.

Example 5 SBA-15 Catalyst Supported with Tantalum Oxide-5

When preparing SBA-15, 130 The SBA-15 catalyst carrying the tantalum oxide of Example 5 was prepared by carrying out the same procedure as in Example 1, except that the catalyst was aged at &lt; RTI ID = 0.0 &gt;

Example 6 KIT-6 Catalyst Containing Tantalum Oxide-1

Regular mesoporous silica (OMS) KIT-6 is described by TW Kim, F. Kleitz, B. Paul and R. Ryoo, J. Am. Chem. Soc. (2005) 127, 7601-7610. 17.0 g of Pluronic, P123, a triplet polymer, was added to a solution of 610.1 g of distilled water, 35%, hydrochloric acid (33.2 g) and butanol (n-butanol) Under vigorous stirring, the mixture was homogeneously mixed. 43.6 g of tetraethyl orthosilicate (TEOS) was added to the homogeneously mixed solution, followed by vigorous stirring for 24 hours at a temperature of 35 ° C. The mixture was aged at a temperature of 35 ° C for 24 hours. After filtration, the dried mesoporous silica (OMS), KIT-6 was prepared by drying for 12 hours at a temperature of 100 ° C. and then heating at a rate of 1 ° C./min and calcining at 550 ° C. for 6 hours.

Next, tantalum oxide was supported on the KIT-5 silica produced by the same impregnation method as in Example 1 to prepare a KIT-6 catalyst carrying tantalum oxide of Example 6.

Example 7 KIT-6 Catalyst Containing Tantalum Oxide-2

When preparing KIT-6, 130 The catalyst was prepared in the same manner as in Example 6, except that the catalyst was aged at &lt; RTI ID = 0.0 &gt; 60 C &lt; / RTI &gt;

Example 8 MMS catalyst carrying tantalum oxide

Mesoporous silica MMS having the same structure as regular mesoporous silica (OMS) MCM-41 was prepared by the method described in Korean Patent Registration No. 0408006 as follows. 32.5 g of 24% by weight hydrogen fluoride (HF) solution was taken in a polypropylene beaker and 10 g of fumed silica was completely dissolved in 25 ml of distilled water to prepare silicon fluoride acid. In a separate beaker, 600 g of distilled water was taken, and 30.6 g of cetyltrimethylammonium bromide was dissolved therein. The solution was then added to the solution, followed by stirring at 60 ° C for 1 hour. Thereto was added 150 g of 28 parts by weight of ammonia water, stirred vigorously at 60 DEG C for 1 hour, and aged while being maintained at 70 DEG C for 16 hours in a drier. The aged mixture was filtered and the precipitate was collected and washed thoroughly with distilled water for 12 hours. The powder dried at 100 ° C was fired at 600 ° C for 4 hours to produce regular mesoporous silica (OMS), MMS.

Next, tantalum oxide was supported on the MMS silica by the same impregnation method as in Example 1 to prepare an MMS-based catalyst carrying the tantalum oxide of Example 8.

Example 9 MCM-41 Catalyst Containing Tantalum Oxide

Regular mesoporous silica (OMS) MCM-41 is prepared by the method according to Jih-Mirn Jehng, Wan-Chen Tung, Chao-His Huang, Israel E. Wachs Microporous and Mesoporous Materials 99 (2007) 299-307 Respectively. Cetyltrimethylammonium bromide (CTAB) (7.8 g) was dissolved in 92.2 g of water and added to 33.9 g of TMSAi (tetramethylammonium silicate), followed by stirring at room temperature for 2 hours. The mixture was aged at a temperature of 100 캜 for 7 days. The aged mixture was filtered to recover the precipitate and dried at 100 ° C. The powder was calcined at 650 ° C. for 6 hours to produce regular mesoporous silica (OMS), MCM-41.

Next, tantalum oxide was supported on the prepared MCM-41 silica by the same impregnation method as in Example 1 to prepare an MCM-41 based catalyst carrying the tantalum oxide of Example 9.

<Example 10> MCM-48 catalyst carrying tantalum oxide

Regular mesoporous silica (OMS) MCM-48 was synthesized by Lingzhi Wang, Jinlong Zhang, Feng Chen, and Masakazu Anpo J. Phys. Chem. C, Vol. 111, No. 37, 2007 13648-13651. 10 ml of TEOS and 56 ml of water were stirred for 30 minutes, and then 1.88 g of NaF was added to the mixed solution and stirred until a white silicate gel was formed. 1.63 g of cetyltrimethylammonium bromide is added to the gel, followed by vigorous stirring. The mixture was stirred at room temperature for 1 hour and then aged at a temperature of 100 DEG C for 72 hours. The aged mixture was filtered to recover the precipitate and dried at 100 ° C. The powder was calcined at 550 ° C. for 6 hours to produce regular mesoporous silica (OMS), MCM-48.

Next, tantalum oxide was supported on the prepared MCM-48 silica by the same impregnation method as in Example 1 to prepare an MCM-48 based catalyst carrying the tantalum oxide of Example 10.

&Lt; Comparative Example 1 > Production of tantalum oxide-supported silica gel catalyst-1

A silica gel catalyst supported on tantalum oxide of Comparative Example 1 was prepared in the same manner as in Example 1, except that Aldrich silica gel (Grade 62) was used as a carrier.

&Lt; Comparative Example 2 > Silica gel-based catalyst carrying tantalum oxide-2

A silica gel catalyst supporting tantalum oxide of Comparative Example 2 was prepared in the same manner as in Example 1 except that Davisil silica gel (Grade 643) was used as a carrier.

&Lt; Comparative Example 3 > Silica gel-based catalyst carrying tantalum oxide-3

The procedure of Example 1 was repeated except that Merck silica gel (Silicagel 60) was used as a carrier to prepare a silica gel catalyst supporting tantalum oxide of Comparative Example 3.

The physical properties of the silica supports used in the catalysts of Examples 1 to 10 and Comparative Examples 1 to 3 were compared and shown in Table 1 below. The catalysts of Examples 1 to 10 and Comparative Examples 1 to 3 had pore sizes The distribution is shown in Fig.

division Silica type Ta ₂ O ₅ content (%) The surface area of silica (m ² / g) Pore volume
(cm &lt; ³ &gt; / g) Average pore size (nm) Example 1 SBA-15 (35) 2 560.8 0.46 3.3 Example 2 SBA-15 (60) 2 696.3 0.47 3.3 Example 3 SBA-15 (80) 2 767.3 0.56 3.4 Example 4 SBA-15 (100) 2 688.0 0.77 5.5 Example 5 SBA-15 (130) 2 582.6 1.48 7.6 Example 6 KIT-6 (35) 2 514.7 0.64 5.0 Example 7 KIT-6 (130) 2 558.6 1.27 9.1 Example 8 MMS 2 797.7 0.85 3.4 Example 9 MCM-41 2 980.0 0.85 3.2 Example 10 MCM-48 2 1187.1 0.76 2.5 Comparative Example 1 Aldrich silica gel
(Grade 62) 2 268.4 1.16 11.3 Comparative Example 2 Davisil silica gel
(Grade 643) 2 257.0 1.16 11.2 Comparative Example 3 Merck silica gel
(Silicagel 60) 2 451.8 0.79 5.0

&Lt; Experimental Example 1 > Measurement of catalyst performance and catalyst life

In order to confirm the excellent reaction performance and catalyst lifetime of the regular mesoporous silica-based catalyst of the present invention, a mixture of ethanol and acetaldehyde was reacted using the catalysts prepared in Examples 1 to 10 and Comparative Examples 1 to 3 , 1 hour and 50 hours, and the selectivity of 1,3-butadiene were calculated. The results are shown in Table 2.

In order to analyze the reaction performance and catalyst life of the catalysts of Examples 1 to 10 and Comparative Examples 1 to 3, each catalyst was precisely weighed in an amount of 0.2 g, placed in a 1/2-inch fixed bed reactor, . As a reactant, a mixture of ethanol and acetaldehyde (ethanol / acetaldehyde molar ratio of 2.75) was injected at a flow rate of 0.011 cc / min and diluted with nitrogen at a flow rate of 4.4 cc / min to obtain a liquid hourly space velocity (LHSV) of 1.0 h ^-1 . &Lt; / RTI &gt;

Reactants and products were analyzed by GC using a GS Alumina column to precisely separate the HP Plot Q column and the C4 isomer.

catalyst Conversion Rate (%) Selectivity of 1,3-butadiene (%) 1hr 50hr 1hr 50hr Example 1 31.2 31.9 77.8 76.5 Example 2 38.2 35.5 75.2 75.0 Example 3 34.7 29.0 72.9 76.0 Example 4 45.3 44.1 79.1 79.0 Example 5 47.6 43.7 79.7 79.7 Example 6 38.9 38.2 77.8 78.5 Example 7 36.5 29.8 77.3 72.8 Example 8 44.4 43.3 78.2 77.6 Example 9 44.5 43.2 77.5 77.5 Example 10 43.4 36.6 76.8 72.1 Comparative Example 1 33.7 25.6 71.8 65.8 Comparative Example 2 31.2 23.4 70.3 65.3 Comparative Example 3 35.4 25.3 77.1 70.2

As shown in Table 2, the catalytic conversion and the 1,3-butadiene selectivity of tantalum oxide having the same contents as those of the catalysts loaded on various types of regular mesoporous silica and conventional silica were compared. As a result, Although the tantalum oxide catalysts supported on the regular mesoporous silica are somewhat different from each other, all of them have a higher conversion and 1,3-butadiene selectivity than the conventional silica gel catalyst, especially the initial 1,3-butadiene selectivity is about 80% And showed excellent reaction activity.

In addition, the regular mesoporous silica-based catalysts of Examples 2 to 9 of the present invention showed a reduction in catalyst conversion of at least 0.7% and a maximum of 6.8% after 50 hours of reaction, and a catalyst conversion rate of 0.7% . Furthermore, the catalysts of Examples 1, 2, 4, 7, 8, and 10 showed a decrease of at least 0.1% and a maximum of 4.7% in 1,3-butadiene selectivity after 50 hours of reaction, Rather, the selectivity of 1,3-butadiene increased. That is, it can be seen that the regular mesoporous silica-based catalysts of Examples 1 to 9 of the present invention not only improved the degree of deactivation after the reaction time but also could be improved rather than before the reaction time.

On the other hand, when Aldrich, Davisil or Merck silica gel of Comparative Examples 1 to 3 was used as a carrier, not only the conversion rate and the 1,3-butadiene selectivity were lower than those of Examples 1 to 10 but also the conversion rate was 10.1 %, And the selectivity of 1,3-butadiene was decreased by 6.9% at the maximum.

From this, it can be seen that the regular mesoporous silica-based catalysts of Examples 1 to 10 are superior to the conventional irregular pore-silica catalysts of Comparative Examples 1 to 3 in conversion and 1,3-butadiene selectivity, , And 3-butadiene synthesis yield is high, which is attributed to the high surface area-active high dispersion activity point of the regular mesoporous silica-based catalysts of the present invention.

Further, it can be seen that the conversion rate after 50 hours and the rate at which the selectivity of 1,3-butadiene is reduced are significantly lower than those of the catalysts of Comparative Examples 1 to 3, and the lifetime of the catalyst is also improved. By using silica having regular mesopores as a carrier, diffusion and mass transfer of reactants and products can be easily performed, and the reaction can be uniformly performed evenly throughout the active sites, and pore clogging due to fine pores , The phenomenon of deactivation of the catalyst is reduced.

Conventionally, in the process for producing 1,3-butadiene from ethanol and acetaldehyde, the selectivity of 1,3-butadiene is low and the regeneration process is required for a short catalyst life. From the above experimental results, Butadiene is not only excellent in selectivity and 1,3-butadiene synthesis yield but also exhibits an effect of improving the process operation efficiency by improving the catalyst activity degradation phenomenon and increasing the regeneration cycle. Thus, Can be solved.

&Lt; Experimental Example 2 >

In order to compare the regeneration ability of the regular mesoporous silica-based catalyst of the present invention after the reaction, the catalysts of Examples 1 to 10 and Comparative Examples 1 to 3, which were inactivated after the reaction, And ethanol and acetaldehyde were reacted under the same conditions as Experimental Example 1 to compare the catalyst performance. The results are shown in Table 3 below.

division

Initial before reproduction Initial after playback
Conversion Rate
(%)
1,3-
butadiene
Selectivity
(%)
Conversion Rate
(%) 1,3-
butadiene
Selectivity (%) Example 1 31.2 77.8 33.4 77.5 Example 2 38.2 75.2 38.2 75.0 Example 3 34.7 72.9 34.3 73.1 Example 4 45.3 79.1 44.8 78.8 Example 5 47.6 79.7 47.1 79.3 Example 6 38.9 77.8 38.4 77.2 Example 7 36.5 77.3 35.9 76.9 Example 8 44.4 78.2 44.0 77.8 Example 9 44.5 77.5 43.9 77.2 Example 10 43.4 76.8 43.5 76.2 Comparative Example 1 33.7 71.8 29.3 65.9 Comparative Example 2 31.2 70.3 28.6 65.2 Comparative Example 3 35.4 77.1 31.2 70.6

As a result, as shown in Table 3, the regular mesoporous silica-based catalysts of Examples 1 to 10 of the present invention exhibited a maximum reduction of the catalyst conversion rate by 0.6% after regeneration of the catalyst, It increased by 2.2%, and in Example 10 it increased by 0.1%. Also, the selectivity of 1,3-butadiene after catalyst regeneration was reduced by only 0.6%, and in Example 3, it was increased by 0.2%.

On the other hand, the catalysts of Comparative Examples 1 to 3 exhibited comparatively excellent reaction activity and 1,3-butadiene selectivity although they were lower than those of Examples 1 to 10 of the present invention. However, after catalyst regeneration, Up to 4.4%, 1,3-butadiene selectivity was reduced by up to 6.5%, and the same performance of the pre-regeneration catalyst was not recovered after regeneration.

From the above results, it can be seen that the catalysts of Examples 1 to 10 of the present invention exhibit excellent 1,3-butadiene selectivity close to 80% even before regeneration, and also exhibit stable reaction activity and 1,3-butadiene selectivity Is recovered. Therefore, the regular mesoporous silica-based catalyst of the present invention not only improves the regenerating ability over the conventional silica-based catalyst but also has an effect of improving the catalyst performance after regeneration, so that it is useful for the production of 1,3-butadiene .

Claims (10)

Catalyst for the production of 1,3-butadiene having a transition metal oxide supported on regular mesoporous silica (OMS) having a surface area of 582.6 to 688.0 m ² / g and an average pore size of 5.5 to 7.6 nm.
The method of claim 1, wherein the regular mesoporous silica is a KIT (Korea Advanced
(MMS), Mobil Composition of Matter (MCM), SBA (Santa Barbara), and TUD (Technische Universiteit Delft) series. Catalyst for the production of 3-butadiene.
delete delete The catalyst for producing 1,3-butadiene according to claim 1, wherein the transition metal oxide is at least one selected from the group consisting of Group III, IV and V transition metal oxides.
The catalyst for producing 1,3-butadiene according to claim 1, wherein the transition metal oxide is at least one selected from the group consisting of hafnium oxide, zirconium oxide, tantalum oxide, zinc oxide and niobium oxide.
The catalyst for producing 1,3-butadiene according to claim 1, wherein the content of the transition metal oxide is 0.1 to 10 parts by weight based on 100 parts by weight of the total catalyst.
Preparing a regular mesoporous silica having a surface area of 582.6 to 688.0 m &lt; ² &gt; / g and an average pore size of 5.5 to 7.6 nm (step 1); And
Impregnating the regular mesoporous silica of step 1 with a transition metal oxide (step 2).
Reacting a mixture of ethanol or an acetaldehyde with a catalyst using a catalyst,
Wherein the catalyst is the catalyst for the production of 1,3-butadiene according to claim 1.
10. The method of claim 9, wherein the reaction is at a temperature of 300 ℃ ~ 400 ℃ range, 0.1 hr ^-1 hr ^-1 range of ~10.0 Wherein the composition ratio of ethanol: acetaldehyde is 1: 0.001 to 1: 0.7 in terms of molar ratio.

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