JP5033522B2 - Catalyst for producing epoxide and method for producing epoxide - Google Patents

Description

  The present invention relates to a catalyst for producing epoxide and a method for producing epoxide. More specifically, the present invention deals with a catalyst for producing an epoxide in which a catalyst component (for example, silver) is supported on an alumina support, and gas phase catalytic oxidation of unsaturated hydrocarbons with molecular oxygen in the presence of the catalyst. The present invention relates to a method for producing an epoxide.

  Many techniques have been proposed for a catalyst (epoxide production catalyst) used in producing an epoxide by vapor-phase catalytic oxidation of an unsaturated hydrocarbon with a molecular oxygen-containing gas.

For example, Patent Document 1 discloses a catalyst in which silver is supported on a support in which a coating layer of amorphous silica is provided on the outer surface of an α-alumina support and on the surface of pores. Patent Document 2 discloses one or two elements selected from the group consisting of elements of the fourth, fifth and sixth periods (for example, titanium, tin, hafnium, etc.) of groups IIIa-VIIa and IIIb-Vb of the periodic table of elements. A catalyst in which silver is supported on an α-alumina carrier containing the above compound is disclosed. Patent Document 3 discloses a catalyst using a support containing high-purity α-alumina, alkaline earth metal oxide, silicon oxide and zirconium oxide. Patent Documents 4 and 5 disclose a catalyst in which silver is supported on a porous α-alumina support. Patent Document 6 discloses that the silicon content (SiO ₂ conversion) is in the range of 0.3 to 11.5 mass%, and the sodium content (Na ₂ O conversion) is in the range of 0.11 to 2.5 mass%. -A catalyst using an alumina support is disclosed.
Japanese Patent Laid-Open No. 2-194939 JP-A-4-363139 JP-A-6-47278 US Pat. No. 5,057,481 European Patent No. 480538 Japanese Patent Laid-Open No. 2001-157839

  The catalysts described in Patent Documents 1 to 6 are excellent in catalyst performance and can be sufficiently satisfied industrially. However, the industrial production scale of epoxides is extremely large, and the amount of unsaturated hydrocarbon used as a raw material is significantly saved even if the selectivity is slightly improved. Therefore, since the economic effect brought about by a slight increase in selectivity is very high, it is still desired to develop a catalyst for producing an epoxide having better catalytic performance.

  On the other hand, industrial catalysts such as epoxide production catalysts are required to be capable of being produced with high reproducibility and high yield in the production process in addition to excellent catalyst performance. For example, in an industrial implementation of a reaction for producing ethylene oxide from ethylene, a heat exchange type multitubular reactor is generally used. As described above, since the production scale of ethylene oxide is very large, Larger ones are also used. Since the amount of the catalyst charged in the reactor also ranges from several tons to several tens of tons, the activity and selectivity of the catalyst produced over a plurality of times in the production facility have little variation (good reproducibility). The more preferable. Moreover, since the said catalyst uses expensive silver as a main component, it is calculated | required to suppress the loss of silver as much as possible (a yield is high) in a catalyst manufacturing process.

  As a means for improving the reproducibility of the catalyst performance and the production yield, improvement by improving the efficiency of the catalyst production facility or optimizing the catalyst production conditions is generally used. However, in the case of a large-scale catalyst manufacturing facility, the current situation is that it is not a problem that can be easily achieved due to a combination of constraints on the facility and complicated control of manufacturing conditions.

  Accordingly, an object of the present invention is to provide an economical epoxide production catalyst that is excellent in activity and selectivity, and that can be produced with high reproducibility and high yield in the catalyst production process.

  Another object of the present invention is to provide a method for producing a corresponding epoxide by gas phase oxidation of an unsaturated hydrocarbon with a molecular oxygen-containing gas in the presence of the catalyst of the present invention.

  In order to solve the above-mentioned problems, the present inventors have intensively studied paying attention to the physical properties of a carrier used for a catalyst for producing an epoxide. As a result, it has been found that when a catalyst for producing an epoxide is prepared using a carrier having many pores having a pore diameter of 100 μm or more, the catalyst performance of the obtained catalyst is improved. Furthermore, it has been found that the use of the above-described carrier reduces silver loss in the catalyst production process and improves the reproducibility of the catalyst performance. And based on these knowledge, it came to complete this invention.

  That is, the first of the present invention is mainly composed of α-alumina, the total pore volume measured by mercury porosimetry is 0.55 ml / g or less, and the pore diameter measured by mercury porosimetry is 100 μm or more. An epoxide production catalyst comprising a carrier having a total pore volume of a region of 0.010 ml / g or more and a catalyst component supported on the carrier.

  The second aspect of the present invention includes a step of producing a corresponding epoxide by gas phase oxidation of an unsaturated hydrocarbon having 2 to 20 carbon atoms with a molecular oxygen-containing gas in the presence of the catalyst of the present invention. It is a manufacturing method of an epoxide.

  According to the first aspect of the present invention, it is possible to provide a catalyst for producing an epoxide which is excellent in activity and selectivity, can be produced with high reproducibility and high yield. According to the second aspect of the present invention, an epoxide can be produced with high productivity. In terms of economy, its industrial utility value is extremely high.

  Embodiments of the present invention will be described below.

  The first of the present invention relates to a catalyst for producing an epoxide. Specifically, the first of the present invention is based on α-alumina, the total pore volume measured by mercury porosimetry is 0.55 ml / g or less, and the pore diameter measured by mercury porosimetry. For producing an epoxide, comprising: a support having a total pore volume in a region of 100 μm or more (hereinafter also referred to simply as “total value”) of 0.010 ml / g or more and a catalyst component supported on the support. It is a catalyst.

  As described above, the catalyst for producing an epoxide of the present invention has other forms (support shape and catalyst) as long as the pore volume (pore volume) and diameter (pore diameter) of the support satisfy a predetermined relationship. The specific form of the component) is not particularly limited.

  As a constituent component of the catalyst of the present invention, first, a carrier is mentioned. This carrier has α-alumina as a main component. Many pores (open pores) exist on the surface of the carrier and communicate with the inside of the carrier particles. In addition, as a value of “pore volume” in the present invention, a value obtained by a mercury intrusion method described in Examples described later is adopted. The only pores that can be measured by the mercury intrusion method are pores (open pores) that are connected to the outside air from the surface of the carrier, and are pores that are not connected to the outside and are isolated inside the carrier. (Closed pores) are not measured. Therefore, strictly speaking, the “pore volume” in the present invention is an “open pore volume” that does not include the “closed pore volume”.

  The first catalyst of the present invention is characterized in that, in the carrier constituting the catalyst, the total pore volume per unit mass of the carrier measured by mercury porosimetry is 0.55 ml / g or less. . When the total pore volume of the carrier exceeds 0.55 ml / g, there is a possibility that a problem that the strength of the carrier is lowered occurs. The total pore volume of the carrier is preferably 0.35 to 0.53 ml / g, more preferably 0.35 to 0.50 ml / g.

  Next, in the first catalyst of the present invention, the total pore volume in the region having a pore diameter of 100 μm or more measured by the mercury intrusion method is 0.010 ml / g or more in the carrier constituting the catalyst. There are features. By increasing the proportion of pores having a relatively large diameter in this way, the catalyst performance such as the activity and selectivity of the resulting catalyst can be improved. Further, when a catalyst for producing an epoxide is produced using such a carrier, the reproducibility of the catalyst and the yield during production can be improved. The total value is preferably 0.012 ml / g or more, more preferably 0.014 ml / g or more. Here, there is no particular limitation on the upper limit value of the total pore volume in the region having a pore diameter of 100 μm or more. However, from the viewpoint of improving the strength of the support and the selectivity when using the obtained catalyst, the total value is described above. Is preferably 0.030 ml / g or less, more preferably 0.020 ml / g or less.

  The mechanism by which the above-described effect is exhibited by the configuration of the present invention is not completely clear, but is estimated as follows. That is, in the case of a so-called supported catalyst in which a catalyst component is supported on a porous carrier, such as a catalyst for ethylene oxide production, the catalyst component needs to be attached (supported) in pores existing inside the carrier. For this reason, the presence of open pores communicating with the inside from the outer surface of the carrier is necessary. In other words, theoretically, no catalyst component is supported on the closed pores of the support. As described above, the carrier used for the epoxide production catalyst of the present invention has a large number of open pores having a relatively large diameter compared to the carrier used for the conventional epoxide production catalyst. In the step of supporting the catalyst, it is considered that the catalyst component-containing solution added to the carrier quickly enters from the open pores existing on the outer surface of the carrier and infiltrates the pores inside the communicating carrier. As a result, the amount of the excess catalyst component-containing solution that remains without being absorbed by the carrier adheres to the wall surface of the supporting device is reduced, so that it is considered that the yield of the catalyst component is finally improved.

  In addition, the presence of pores having an appropriate pore size allows the catalyst component-containing solution to uniformly infiltrate into the communicating pores by capillary action, and the catalyst component particles are also highly dispersed and supported within the support. As a result, it is considered that uneven distribution of silver is prevented, high activity and high selectivity are exhibited, and reproducibility in catalyst production over a plurality of times is improved. It should be noted that these mechanisms are only based on speculation, and even if the effects of the present invention as described above are actually obtained by other mechanisms, the technical scope of the present invention is not affected at all. Absent.

  Further, in the first more preferable embodiment of the present invention, the ratio of the total value to the total pore volume of the support is not particularly limited, but in consideration of improving the selectivity when using the catalyst. The ratio is preferably 3.0% or more, more preferably 3.2% or more, and further preferably 3.5% or more. In addition, although there is no restriction | limiting in particular also about the upper limit of the said ratio, From a viewpoint of improving the intensity | strength of a support | carrier, the said ratio becomes like this. Preferably it is less than 5.0%, More preferably, it is less than 4.5%, More preferably, it is less than 4.0%. The ratio of the total value to the total pore volume of the carrier is calculated according to the following formula 1.

  The composition of the carrier is not particularly limited except that the main component is α-alumina. Here, the carrier “having α-alumina as a main component” means that the content of α-alumina in the carrier is 90% by mass or more based on the total mass of the carrier. The content of α-alumina in the carrier is preferably 95% by mass or more, more preferably 98% by mass or more. The other composition is not particularly limited as long as it has α-alumina as a main component, but the support can contain, for example, an oxide of an alkali metal or alkaline earth metal or an oxide of a transition metal. Although there is no restriction | limiting in particular also about these content, Preferably content of the oxide of an alkali metal or alkaline-earth metal is 0-5 mass% in conversion of an oxide, More preferably, it is 0.01-4 mass %. The content of the transition metal oxide is preferably 0 to 5% by mass, more preferably 0.01 to 3% by mass in terms of oxide.

  The support also usually contains silica (silicon oxide). Although there is no restriction | limiting in particular also about the content of the silica in a support | carrier, Preferably it is 0.1-2 mass%, More preferably, it is 0.3-1.5 mass%, More preferably, 0.5-1. 0% by mass.

  The composition of the carrier and the content of each component described above can be determined using a fluorescent X-ray analysis method.

  The shape of the carrier is not particularly limited, and conventionally known knowledge can be appropriately referred to in addition to a ring shape, a spherical shape, a cylindrical shape, and a pellet shape. Moreover, there is no restriction | limiting in particular also about the size (average diameter) of a support | carrier, Preferably it is 3-20 mm, More preferably, it is 5-10 mm.

There is no particular restriction on the BET specific surface area of the support is preferably 0.03~10m ² / g, more preferably 0.5~5.0m ² / g, more preferably 1.0 to 2 0.5 m ² / g. When the BET specific surface area of the support is 0.03 m ² / g or more, sufficient pores for supporting the catalyst component are secured, and a catalyst having excellent catalyst performance can be obtained. On the other hand, when the BET specific surface area of the support is 10 m ² / g or less, the pore diameter of the support is maintained at a certain large value, and the sequential oxidation of the epoxide during epoxide production using the produced catalyst can be suppressed. The BET specific surface area of the carrier can be determined by an apparatus generally used for measuring the specific surface area of the substance.

In the infrared absorption spectrum measured by the KBr tablet method, the carrier preferably has substantially no infrared absorption spectrum in the region of wave numbers of 3,150 to 3,800 cm ⁻¹ . The infrared absorption spectrum of “substantially zero” means that the infrared absorption peak in the region of wave numbers 3,150 to 3,800 cm ⁻¹ is substantially in the infrared absorption spectrum of the carrier measured by the KBr tablet method. This means that it cannot be recognized, that is, there is no clear infrared absorption peak in the spectral region. Specifically, it means that the peak area of absorbance in the spectral region is substantially zero. More specifically, in the measured infrared absorption spectrum, the straight line connecting the absorbance at the absorbance and 3,800Cm ^-1 in wavenumber 3,150Cm ^-1, the wave number region of 3,150～3,800Cm ^-1 red It means that the line of the outer absorption spectrum substantially overlaps.

  The infrared absorption spectrum of the carrier is measured by a conventionally known KBr tablet method. Specifically, the support is ground to a powder form, 1 part by weight of the support and 75 parts by weight of KBr are uniformly mixed, and then the infrared absorption spectrum of the pressed product is measured.

It is unclear exactly what the infrared peak in the region of the carrier wavenumber of 3,150 to 3,800 cm ⁻¹ is derived from, but it is presumed to be derived from SiOH.

  The height of the infrared absorption peak is preferably 0.1 or less, more preferably 0.05 or less, and further preferably 0.03 or less.

  The height of the infrared absorption peak is obtained by the following method.

FIG. 1 is a graph showing an infrared absorption spectrum used for calculating the infrared absorption peak height of a carrier mainly composed of α-alumina used in the present invention. In the graph shown in FIG. 1, an infrared absorption spectrum in the vicinity of 3,000 to 4,000 cm ⁻¹ of the carrier is shown. Based infrared absorption spectrum (in the figure, the thick solid line) shown in FIG. 1 in the absorbance at a wave number 3,150Cm ^-1 X, the absorbance at a wave number 3,800Cm ^-1 and Y, a straight line connecting the X and Y Line (broken line in the figure).

Of the absorption spectrum having a wave number of 3,150 to 3,800 cm ⁻¹ , let A be the portion with the highest absorbance, and let B be the point where the perpendicular line from A (the thin solid line in the figure) crosses the base line. Then, the value of AB is set as the height of the infrared absorption peak described above (that is, peak height = absorbance at point A−absorbance at point B). In addition, when calculating | requiring peak height, background (baseline) correction | amendment of an absorption spectrum shall not be performed.

  The first catalyst of the present invention has a configuration in which a catalyst component is supported on the carrier described above. The specific form of the catalyst component is not particularly limited, and conventionally known knowledge can be referred to as appropriate, but it is preferable that silver is essential as the catalyst component. In addition to silver, a catalyst component generally used as a reaction accelerator may be supported on a carrier. Representative examples of reaction accelerators include alkali metals, specifically lithium, sodium, potassium, rubidium, and cesium. Besides alkali metals, thallium, sulfur, chromium, molybdenum, tungsten, rhenium and the like can also be used as reaction promoters. As for these reaction accelerators, only 1 type may be used independently and 2 or more types may be used together. Of these, cesium is preferably used as the reaction accelerator.

  There is no restriction | limiting in particular about the load of silver and reaction accelerator, What is necessary is just to carry | support the amount effective for manufacture of an epoxide. For example, in the case of silver, the supported amount is preferably 1 to 30% by mass, more preferably 5 to 20% by mass, and further preferably 8 to 15% by mass based on the mass of the epoxide production catalyst. The amount of the reaction accelerator supported is usually 0.001 to 2% by mass, preferably 0.01 to 1% by mass, and more preferably 0.1 to 0% by mass based on the mass of the epoxide production catalyst. 0.7% by mass.

  The epoxide production catalyst of the present invention can be prepared according to a conventionally known production method for an epoxide production catalyst, except that the above-mentioned carrier is used as the carrier.

  As a method for preparing the carrier, it is known that the physical properties of the carrier can be controlled by adopting the following method. That is, 1) a method of adding a pore-forming agent having a desired size and amount to a mother powder mainly composed of α-alumina, and 2) preparing at least two kinds of mother powders having different physical properties at a desired mixing ratio. 3) a method of firing the carrier at a desired temperature for a desired time, and the like, and a method combining these methods is also known. These preparation methods are described in, for example, “Characteristics of Porous Materials and Their Application Technologies”, supervised by Satoshi Takeuchi, published by Fuji Techno System Co., Ltd. (1999). Reference can also be made to JP-A-5-329368, JP-A-2001-62291, JP-A-2002-136868, JP-A-2984740, JP-A-3256237, JP-A-3295433, and the like.

  In addition, it becomes possible to prepare the support | carrier which has the pore distribution which is the characteristic structure of this invention by implementing the method mentioned above individually or in combination suitably. Specifically, the pore diameter of the finished carrier can be increased by adding a pore-forming agent having a large particle size during the production of the carrier or by lowering the firing temperature of the carrier. In general, a method of controlling the particle size of the pore forming agent can be employed.

  Hereinafter, an example of a method for producing the first epoxide production catalyst of the present invention using the above-mentioned carrier will be described. However, the technical scope of the present invention should be determined based on the description of the claims. The method is not limited to the following method.

  First, a carrier is prepared. The carrier may be boiled and washed any number of times using distilled water or ion-exchanged water and dried in advance.

  On the other hand, a solution for supporting silver on a carrier is prepared. Specifically, a silver compound alone or a complexing agent for forming a silver complex or, if necessary, a reaction accelerator is added to a solvent such as water.

  Here, examples of the silver compound include silver nitrate, silver carbonate, silver oxalate, silver acetate, silver propionate, silver lactate, silver citrate, and silver neodecanoate. Examples of the complexing agent include monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, and propylenediamine. Each of these silver compounds and complexing agents may be used alone or in combination of two or more.

  Next, the carrier prepared above is impregnated with the solution obtained above. In this case, the reaction accelerator may be dissolved in the silver ammine complex aqueous solution and impregnated at the same time before the support is impregnated with the aqueous solution, or may be supported after supporting the silver.

  Subsequently, the carrier is dried and fired. Drying is preferably performed at a temperature of 80 to 120 ° C. in an atmosphere of air, oxygen, or an inert gas (for example, nitrogen). The firing is preferably performed at a temperature of 150 to 700 ° C., preferably 200 to 600 ° C., in an atmosphere of air, oxygen, or an inert gas (for example, nitrogen). In addition, baking may be performed only in one step or may be performed in two or more steps. As preferable firing conditions, the first stage firing is performed in an air atmosphere at 150 to 250 ° C. for 0.1 to 10 hours, and the second stage firing is performed in an air atmosphere at 250 to 450 ° C. for 0.1 to 10 hours. The conditions for 10 hours are mentioned. More preferably, after the two-step baking, the third-step baking is performed at 450 to 700 ° C. for 0.1 to 10 hours in an inert gas (eg, nitrogen, helium, argon, etc.) atmosphere. Good.

  In the second aspect of the present invention, a corresponding epoxide is produced by gas phase oxidation of an unsaturated hydrocarbon having 2 to 20 carbon atoms with a molecular oxygen-containing gas in the presence of the first epoxide production catalyst of the present invention. A method for producing an epoxide comprising steps.

  The manufacturing method of the 2nd epoxide of this invention can be performed in accordance with a conventional method except the point which uses the catalyst for 1st epoxide manufacture of this invention as a catalyst.

The reaction raw material is an unsaturated hydrocarbon having 2 to 20 carbon atoms. Specifically, it may be a compound having 4 to 20 carbon atoms and having no allyl hydrogen in addition to ethylene and propylene. In the present invention, “allyl hydrogen” means two hydrogens bonded to the carbon adjacent to the double bond of the allyl group represented by CH ₂ ═CH—CH ₂ —. “None” means not having at least one of the two hydrogens. The “compound having no allyl hydrogen” is specifically a compound represented by the following chemical formula 1.

In the formula, R ₁ is a hydrogen atom or an alkyl group, R ₂ is an aryl group, a tertiary alkyl group, or —C (R ₃ ) ═CH ₂ , and R ₃ is a hydrogen atom or an alkyl group.

Further, the “compound having no allyl hydrogen” may be a linear compound or may have a branch. Furthermore, a ring may be included. Here, as an alkyl group represented by R ₁ and R ₃ , a methyl group, an ethyl group, a butyl group, a heptyl group, an octyl group and the like can be mentioned independently. Examples of R ₂ include a t-butyl group and a phenyl group.

  The “compound having no allyl hydrogen” preferably has 4 to 12 carbon atoms, more preferably 4 to 8 carbon atoms. Specific examples include compounds such as 1,3-butadiene, tert-butylethylene, and styrene.

  Hereinafter, for convenience of explanation, the second production method of the present invention will be described by taking as an example the production of ethylene oxide by catalytic vapor phase oxidation of ethylene.

As an example of reaction conditions in such a production method, for example, general conditions on an industrial production scale, that is, a reaction temperature of 150 to 300 ° C., preferably 180 to 280 ° C., a reaction pressure of ^{2 to} 40 kg / cm ² G, preferably the 10~30kg / ^cm 2 G, a space velocity 1,000~30,000hr ^-1 (STP), preferably 3,000~8,000hr ^-1 (STP) are adopted. Examples of the raw material gas to be brought into contact with the catalyst include 0.5 to 40% by volume of ethylene, 3 to 10% by volume of oxygen, 1 to 30% by volume of carbon dioxide, the balance being an inert gas such as nitrogen, argon or water vapor, methane, ethane, or the like. And those containing 0.1 to 10 ppm (capacity) of halides such as ethylene dichloride and diphenyl chloride as reaction inhibitors. Examples of the molecular oxygen-containing gas used in the production method of the present invention include air, oxygen, and enriched air.

  The effects of the present invention will be described using the following examples and comparative examples. The following examples specifically illustrate examples of producing ethylene oxide and 3,4-epoxy-1-butene using the catalyst of the present invention. However, the technical scope of the present invention is not limited only to the following examples. In this example, various parameters were measured by the following methods and conditions. In the following description, “parts” means parts by mass.

<Measurement of pore distribution spectrum and pore volume of carrier>
Measured by mercury intrusion method. Specifically, a carrier heat treated (degassed) at 200 ° C. for at least 30 minutes is used as a sample, and Autopore III 9420W (manufactured by Shimadzu Corporation) is used as a measuring device, and 0.5 to 60,000 psia (0.0034) is used. ˜413.7 MPa), an equivalent time of 10 seconds, and 60 measurement points, and a pore distribution spectrum and a pore volume were calculated by the Washburn equation represented by the following Equation 2. At that time, the surface tension of mercury is 480 mN / m, and the contact angle of mercury is 130 deg. It was.

<Calculation of conversion rate and selectivity>
The conversion rate and selectivity described in Examples and Comparative Examples were calculated according to the following Equation 3 and Equation 4.

<Calculation of silver loading rate and silver yield>
The silver loading rate and the silver yield during catalyst production were calculated according to the following formulas 5 and 6, respectively.

<Measurement of infrared absorption spectrum>
In this example, the infrared absorption spectrum of the carrier was measured under the following conditions.

  (1) KBr (300 mg) and the carrier to be measured (4 mg) are mixed well while being pulverized in an agate mortar.

  (2) 120 mg of the mixed powder is weighed, set in a tablet molding machine, and degassed with a vacuum pump for 3 minutes.

(3) Next, deaeration is performed for 3 minutes while applying a pressure of 600 kg / cm ² G (the shape of the completed sample is a disk having a diameter of 10 mm).

  (4) A disk-shaped sample is set in an infrared absorption spectrum measuring apparatus and heated at 110 ° C. for 1 hour.

(5) After returning the sample to room temperature, the infrared absorption spectrum of the sample is measured at a resolution of 4 cm ⁻¹ after 100 integrations (infrared absorption spectrum measurement apparatus used: EXCALIBUR Series manufactured by VARIAN).

Example 1
1 liter of distilled water was added to 1 liter of carrier a made of α-alumina (outer diameter 8 mm, inner diameter 4 mm, length 8 mm), boiled and washed under normal pressure for 30 minutes, and then the washing solution was removed and washed with distilled water. Furthermore, after this boiling washing was repeated twice, it was dried at 120 ° C. for 3 hours.

  A slurry was prepared by uniformly mixing 52.0 parts of silver oxalate, 0.43 part of cesium nitrate and 100 parts of distilled water. While cooling this in a water bath, 22.5 parts of ethylenediamine was added, and a silver-containing solution was added. Prepared.

  100 g of carrier a that had been heated to 100 ° C. in advance was placed in a eggplant flask having an internal volume of 1000 ml, and then a silver-containing solution was added. Here, the volume of the silver-containing solution was adjusted so that the silver loading of the finished catalyst was 15.0% by mass. The volume of the silver-containing solution to be added was adjusted by adding distilled water until the volume of the silver-containing solution was equal to the pore volume in 100 g of the carrier. In addition, the volume of the silver containing solution to add was computed according to following Numerical formula 7.

  For other examples and comparative examples, a silver-containing solution having a desired volume was obtained by the same calculation.

  The eggplant flask to which the carrier and the silver-containing solution were added was set on a rotary evaporator, immersed in a boiling water bath, and evaporated to dryness with stirring under reduced pressure. Next, heat treatment was performed at 400 ° C. for 20 minutes in an air stream using a hot air dryer. Furthermore, this was heat-processed at 550 degreeC for 3 hours in nitrogen atmosphere, and catalyst A1 for ethylene oxide manufacture was obtained. Table 1 shows the measurement results of the BET specific surface area of the carrier a used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. In addition, Table 2 shows the yield of silver during the production of the catalyst A1.

(Examples 2-3)
In order to confirm the reproducibility, in the same manner as in Example 1, catalysts A2 and A3 for producing ethylene oxide using the carrier a were obtained. Table 2 shows the yield of silver during the production of the catalysts A2 and A3.

(Examples 4 to 6)
Catalysts B1 to B3 for producing ethylene oxide were obtained in the same manner as in Example 1 except that the carrier b was used in place of the carrier a and the amount of cesium nitrate added was 0.37 parts. Table 1 shows the measurement results of the BET specific surface area of the carrier b used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Table 2 shows the yield of silver during the production of the catalysts B1 to B3.

(Examples 7 to 9)
Catalysts C1 to C3 for ethylene oxide production were obtained in the same manner as in Example 1 except that the carrier c was used instead of the carrier a and the addition amount of cesium nitrate was 0.67 parts. Table 1 shows the measurement results of the BET specific surface area of the carrier c used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Table 2 shows the yield of silver during the production of the catalysts C1 to C3.

(Examples 10 to 12)
Catalysts D1 to D3 for producing ethylene oxide were obtained in the same manner as in Example 1 except that the carrier d was used instead of the carrier a. Table 1 shows the measurement results of the BET specific surface area of the carrier d used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Further, Table 2 shows the yield of silver during the production of the catalysts D1 to D3.

(Comparative Examples 1-3)
Catalysts E1 to E3 for producing ethylene oxide were obtained in the same manner as in Example 1 except that the carrier e was used instead of the carrier a and the addition amount of cesium nitrate was 0.37 parts. Table 1 shows the measurement results of the BET specific surface area of the carrier e used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Table 2 shows the yield of silver during the production of the catalysts E1 to E3.

(Comparative Examples 4-6)
Catalysts F1 to F3 for ethylene oxide production were obtained in the same manner as in Example 1 except that the carrier f was used instead of the carrier a and the addition amount of cesium nitrate was 0.37 parts. Table 1 shows the measurement results of the BET specific surface area of the carrier f used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Further, Table 2 shows the yield of silver during the production of the catalysts F1 to F3.

(Comparative Examples 7-9)
Catalysts G1 to G3 for producing ethylene oxide were obtained in the same manner as in Example 1 except that the carrier g was used instead of the carrier a and the amount of cesium nitrate added was 0.67 parts. Table 1 shows the measurement results of the BET specific surface area of the carrier g used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Further, Table 2 shows the yield of silver during the production of the catalysts G1 to G3.

(Comparative Examples 10-12)
Catalysts H1 to H3 for producing ethylene oxide were obtained by the same method as in Example 1 except that the carrier h was used instead of the carrier a. Table 1 shows the measurement results of the BET specific surface area of the carrier h used, the total pore volume by the mercury intrusion method, the volume of pores having a pore diameter of 100 μm or more, and the infrared absorption spectrum. Table 2 shows the yield of silver when the catalysts H1 to H3 were produced.

(Example 13)
The catalysts A1 to H3 obtained in Examples 1 to 12 and Comparative Examples 1 to 12 were each pulverized and sieved to 600 to 850 mesh, and 1.2 g each was put into a stainless steel reaction tube having an inner diameter of 3 mm and a tube length of 600 mm. Each was filled, and the gas phase oxidation reaction of ethylene was performed under the following conditions. Table 2 shows the reaction temperature and ethylene oxide selectivity when the ethylene conversion is 10%.

<Gas oxidation reaction conditions for ethylene>
Space velocity: 6,000 hr ^-1
Reaction pressure: 20 kg / cm ²
Raw material gas: 23% by volume of ethylene, 7.8% by volume of oxygen, 7% by volume of carbon dioxide, 2.0% by volume of ethylene dichloride and the balance (methane, nitrogen, argon and ethane)
(Example 14)
Catalyst I was obtained in the same manner as in Example 1 except that the amount of cesium nitrate added was 4.25 parts.

  The catalyst I is pulverized and sieved to 10 to 18 mesh, and 3.0 g of the catalyst I is filled into a stainless steel reaction tube having an inner diameter of 7.5 mm and a tube length of 600 mm. An oxidation reaction was performed. Table 3 shows the 1,3-butadiene conversion rate and 3,4-epoxy-1-butene selectivity when the reaction temperature is 195 ° C.

<Gas oxidation reaction conditions for 1,3-butadiene>
Gas flow rate: 300cm ³ / min
Reaction pressure: 0.3 kg / cm ²
Source gas: 1,3-butadiene 9% by volume, oxygen 18% by volume, chlorobutane 3.0% by volume, and the balance (helium)
(Comparative Example 13)
Catalyst J was obtained in the same manner as in Example 1, except that the carrier e was used instead of the carrier a and the addition amount of cesium nitrate was 3.66 parts.

  A gas phase oxidation reaction of 1,3-butadiene was performed in the same manner as in Example 14 except that the catalyst J was used instead of the catalyst I. Table 3 shows the 1,3-butadiene conversion rate and 3,4-epoxy-1-butene selectivity when the reaction temperature is 195 ° C.

  From the results shown in Table 2 above, according to the present invention, the catalyst is formed using a carrier whose total pore volume and pore distribution satisfy the prescribed regulations, and thus the yield of silver during production is excellent, and A catalyst for producing an epoxide having excellent selectivity at the time of producing an epoxide such as ethylene oxide can be provided with good reproducibility. Moreover, the catalyst for epoxide production which shows the outstanding conversion rate and selectivity can be provided even if it is a case where a 1, 3- butadiene is used as a reaction raw material by comprising a catalyst using the said support | carrier.

It is a graph showing the infrared absorption spectrum used for calculation of the infrared absorption peak height of the support | carrier which has (alpha) -alumina as a main component used by this invention.

Claims (9)

α-alumina as a main component, the total pore volume measured by the mercury intrusion method is 0.55 ml / g or less, and the total pore volume in the region having a pore diameter of 100 μm or more measured by the mercury intrusion method is A carrier that is 0.010 ml / g or more;
A catalyst component supported on the carrier;
A catalyst for producing an epoxide, comprising: The catalyst for epoxide production according to claim 1, wherein the total value is from 0.010 to 0.030 ml / g.   In infrared absorption spectrum measured by KBr tableting method, wave number 3,150-3,800 cm ^-1 The catalyst for producing an epoxide according to claim 1 or 2, wherein the infrared absorption spectrum in the region of is substantially zero. The catalyst for epoxide production according to any one of claims 1 to 3 , wherein a ratio of the total value to the total pore volume is 3.0% or more. The catalyst for producing an epoxide according to any one of claims 1 to 4 , wherein the support has a silica content of 0.1 to 2 mass%. In the presence of the catalyst according to any one of claims 1 to 5 , the method comprises a step of producing a corresponding epoxide by gas phase oxidation of an unsaturated hydrocarbon having 2 to 20 carbon atoms with a molecular oxygen-containing gas. The manufacturing method of an epoxide. The production method according to claim 6 , wherein the unsaturated hydrocarbon is ethylene and the epoxide is ethylene oxide. The production method according to claim 6 , wherein the unsaturated hydrocarbon is an unsaturated hydrocarbon having 4 to 20 carbon atoms and having no allyl hydrogen. The production method according to claim 8 , wherein the unsaturated hydrocarbon is 1,3-butadiene and the epoxide is 3,4-epoxy-1-butene .

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