Catalyst for producing epoxides and method for producing epoxides

Abstract

To provide a catalyst for producing epoxides with excellent durability, enabling efficient production of epoxides by using glycols such as 1,2-propanediol as a raw material, and a method for producing epoxides employing the catalyst.SOLUTION: A catalyst for producing epoxides, which is used in a reaction for producing epoxides from glycols, comprises a first component composed of an alkali metal and a second component composed of at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a catalyst for producing epoxides and a method for producing epoxides. More specifically, the present invention relates to a catalyst for producing epoxides that can efficiently produce epoxides from glycols and a method for producing epoxides. [Background technology]

[0002] In recent years, efforts to prevent global warming have been actively promoted worldwide, and the bio-based conversion of various chemicals has attracted attention from the perspective of carbon recycling. Glycerin is a large-scale by-product of processes such as biodiesel production, and is relatively inexpensive to obtain. It can be converted into glycols such as 1,2-propanediol, and these glycols are also considered useful biomass feedstocks. In addition to methods using glycerin as a starting material, methods such as hydrogenolysis of sugars have also been proposed to produce glycols, and glycols are expected to become useful as inexpensive biomass feedstocks in the future.

[0003] Different products can be obtained depending on how glycols are dehydrated, and one known method is to synthesize epoxides from glycols. For example, known methods include a method of producing an epoxide by heating a 1,2-glycol stream over an alkali metal phosphate catalyst (e.g., Patent Document 1), a method of producing an epoxide by heating a 1,2-glycol stream over an alkali metal silicate catalyst (Patent Document 2), and a method of using a catalyst containing a complex salt of an alkali metal oxide, an oxide of a divalent cation, and silicic acid (Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 59-170082 [Patent Document 2] Japanese Patent Application Publication No. 59-170083 [Patent Document 3] Japanese Patent Application Laid-Open No. 2014-83473 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional catalysts used in the methods have problems such as a low conversion rate of glycols to epoxides, a low yield of epoxides, and poor durability, making them less practical.

[0006] In view of the above-mentioned current situation, an object of the present invention is to provide a catalyst for producing epoxides, which has excellent durability and enables efficient production of epoxides using glycols such as 1,2-propanediol as raw materials, and a method for producing epoxides using the catalyst. [Means for solving the problem]

[0007] In order to solve the above problems, the present inventors have conducted extensive research on catalysts to be used in the reaction of producing epoxides from glycols, and have found that a catalyst containing an alkali metal and at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum can improve the yield of epoxides and also has excellent durability, thereby completing the present invention.

[0008] That is, the present invention provides the following aspects. <1> A catalyst for producing epoxides, which is used in a reaction for producing epoxides from glycols, comprising a first component consisting of an alkali metal and a second component consisting of at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum. <2> The alkali metal includes potassium or cesium. <1> The catalyst for producing epoxides according to claim 1. <3> The above-mentioned method is characterized in that the R value, which is the ratio of the number of moles of the second component to the number of moles of the first component, is 0.1 to 1.5. <1> or <2> The catalyst for producing epoxides according to claim 1. <4> The first component and the second component are supported on a carrier, and the support rate is 2 to 47 mass %. <1> ~ <3> 1. The catalyst for producing epoxides according to claim 1, <5> A method for producing epoxides, comprising a reaction step of producing epoxides from glycols in the presence of a catalyst, the catalyst comprising an alkali metal and at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum. <6> The reaction in the reaction step is a gas-phase dehydration reaction. <5> 1. A method for producing epoxides according to claim 1. <7> In the reaction step, the ratio W / F of the mass W (kg) of the catalyst to the gas flow rate F (mol / sec) of the glycols is 5 kg sec / mol or more and 600 kg sec / mol or less. <5> or <6> 1. A method for producing epoxides according to claim 1. <8> The reaction temperature in the reaction step is 300°C or higher. <5> ~ <7> 1. The method for producing an epoxide according to any one of the preceding claims. <9> The glycol is a straight-chain hydrocarbon. <5> ~ <8> 1. The method for producing an epoxide according to any one of the preceding claims. [Effects of the Invention]

[0009] The catalyst for producing epoxides of the present invention has excellent durability and is capable of efficiently producing epoxides from glycols. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a graph showing the 1,2-propanediol conversion, propylene oxide selectivity, and propylene oxide yield when catalysts A to J were used. [Figure 2]FIG. 2 is a graph showing the relationship between the catalyst loading rate and the 1,2-propanediol conversion rate, propylene oxide selectivity, and propylene oxide yield. [Figure 3] FIG. 3 is a graph showing the relationship between the R value of the catalyst and the 1,2-propanediol conversion rate, propylene oxide selectivity, and propylene oxide yield. [Figure 4] FIG. 4 is a graph showing the ratio of the catalytic activity of catalysts A, H, and I after 5 hours of reaction to the catalytic activity at the initial stage of reaction. [Figure 5] FIG. 5 is a graph showing the relationship between the reaction temperature and the 1,2-propanediol conversion rate, the propylene oxide selectivity, and the propylene oxide yield. [Figure 6] FIG. 6 is a graph showing the relationship between the linear carbon number of the raw material glycol, the conversion rate of the raw material glycol, and the selectivity and yield of epoxides depending on the linear carbon number of each raw material glycol. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below. In addition, a combination of two or more of the individual preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

[0012] 1.Catalyst for producing epoxides The present invention relates to a catalyst for use in a reaction for producing epoxides from glycols, the catalyst comprising a first component comprising an alkali metal and a second component comprising at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum.

[0013] Use of the catalyst for producing epoxides of the present invention can improve the yield of epoxides in a reaction for producing epoxides from glycols. Furthermore, the catalyst for producing epoxides also has excellent durability, allowing for efficient and stable production of epoxides over a long period of time. The catalyst for producing epoxides of the present invention has excellent durability and can improve the yield of epoxides from glycols. It is believed that the catalyst for producing epoxides of the present invention contains both an alkali metal and at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum, thereby forming acid sites and base sites with appropriate strength, thereby effectively promoting the target reaction and suppressing coke formation, which is a cause of deterioration.

[0014] The catalyst for producing epoxides of the present invention comprises a first component consisting of an alkali metal and a second component consisting of at least one element selected from the group consisting of boron, aluminum, zirconium and lanthanum.

[0015] (1st component) Examples of the alkali metal (hereinafter also referred to as "first component") include lithium, sodium, potassium, rubidium, cesium, and francium. Among these, the alkali metal preferably includes potassium or cesium, and more preferably includes cesium, in terms of higher activity and more efficient production of epoxides. The catalyst may include one or more alkali metals.

[0016] Examples of raw material compounds containing the first component include nitrates, phosphates, acetates, carbonates, hydroxides, oxides, chlorides, sulfates, etc. Among these, nitrates, acetates, and carbonates of the first component are preferred, and nitrates are more preferred.

[0017] (Second component) The catalyst also contains at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum (hereinafter also referred to as the "second component"). The second component is preferably at least one element selected from the group consisting of boron, aluminum, and zirconium, in terms of high epoxide yield and excellent durability.

[0018] Examples of raw material compounds containing the second component include nitrates, phosphates, acetates, carbonates, hydroxides, oxides, chlorides, sulfates, etc. Among these, nitrates, acetates, and carbonates are preferred, and nitrates are more preferred.

[0019] In the catalyst, the R value, which is the ratio of the number of moles of the second component to the number of moles of the first component (R value = number of moles of second component / number of moles of first component), is preferably 0.1 to 1.5, more preferably 0.25 to 0.9, and even more preferably 0.35 to 0.55, in order to obtain a high epoxide yield. When a plurality of first components and second components are contained, the R value is calculated based on the total number of moles of each.

[0020] The catalyst may contain one or more other elements in addition to the first and second components. Examples of such other elements include magnesium, barium, and cerium. A support component may also be used in addition to the first and second components and other elements. A preferred embodiment of the catalyst is, for example, a support on which a compound containing the first and second components is supported.

[0021] (Carrier) The carrier may be one containing an inorganic oxide, such as silica, alumina, titania, zirconia, ceria, etc. Among these, the inorganic oxide is preferably at least one metal oxide selected from the group consisting of silica (SiO), alumina (AlO), titania (TiO), zirconia (ZrO), and ceria (CeO) because of its large specific surface area, and silica is more preferred because of its chemically inactive surface and large surface area.

[0022] The shape of the carrier is not particularly limited and may be, for example, spherical, cylindrical, crushed, etc. The size of the carrier is not particularly limited and may be appropriately selected depending on the size of the reactor, etc.

[0023] The content of the first component in the catalyst is preferably 1.0 to 22.0 mol %, more preferably 3.2 to 13.5 mol %, and even more preferably 6.1 to 8.7 mol %, based on 100 mol % of all metal elements contained in the catalyst.

[0024] The content of the second component in the catalyst is preferably 0.1 to 15 mol %, more preferably 1.8 to 9.0 mol %, and even more preferably 3.0 to 4.5 mol %, based on 100 mol % of all metal elements contained in the catalyst.

[0025] In the catalyst, the first component and the second component are supported on a support, and the support rate is preferably 2 to 47 mass%, more preferably 9.8 to 35 mass%, and even more preferably 15 to 27 mass%, in order to increase the yield of epoxides. The support rate is the ratio of the total mass of the first component and the second component, when converted into their respective oxide amounts, to the total mass of the first component, the second component, other elements, and the support component contained in the catalyst, when converted into their respective oxide amounts. In the present invention, the support rate is calculated using CsO as the oxide of Cs, KO as the oxide of K, BO as the oxide of B, AlO as the oxide of Al, ZrO as the oxide of Zr, and LaO as the oxide of La.

[0026] Furthermore, when a carrier component is contained in addition to the first and second components, the loading rate is calculated assuming that silica is SiO2, alumina is Al2O3, titania is TiO2, zirconia is ZrO2, or ceria is CeO2.

[0027] Furthermore, when magnesium, barium, or cerium is contained as other elements in addition to the first and second components, the loading rate is calculated as MgO as the oxide of Mg, BaO as the oxide of Ba, and CeO2 as the oxide of Ce. Furthermore, when elements other than the first and second components, other elements, and support components are contained, the loading rate is calculated as the most abundant oxidation state at 1000°C.

[0028] In the catalyst, the first component and the second component may each exist as an oxide, or may exist as a crystalline compound or composite oxide containing the first component and the second component.

[0029] The shape and size of the catalyst are not particularly limited, and may be appropriately adjusted depending on the size and shape of the reactor to be used.

[0030] <Catalyst manufacturing method> The method for producing the catalyst is not particularly limited, and the catalyst can be produced by known methods such as impregnation, precipitation, coprecipitation, solid-phase synthesis, drum drying, spray drying, etc. For example, there is a method in which an aqueous solution or dispersion of a compound containing the first component and the second component is prepared, the aqueous solution is brought into contact with a support, and then the support is dried and / or calcined to support the catalyst components on the support.

[0031] The method for preparing a dispersion or aqueous solution of a compound containing the first and second components is not particularly limited and may be any known method, such as mixing one or more compounds containing the first or second component in a solvent. The order in which two or more compounds containing the first or second component are mixed is not particularly limited, and they may be mixed sequentially or simultaneously, but simultaneous mixing is preferred. Examples of the solvent include water (preferably pure water such as ion-exchanged water or distilled water).

[0032] The drying can be carried out by a known method, for example, by evaporating the solvent by heating with a blower dryer, etc. The drying temperature may be any temperature at which the solvent in the dispersion or aqueous solution evaporates, and when the solvent is water, for example, the drying temperature is preferably 50 to 250°C, more preferably 70 to 180°C, and even more preferably 80 to 150°C.

[0033] The drying time is not particularly limited as long as the solvent can be sufficiently evaporated, and is, for example, preferably 10 minutes to 80 hours, more preferably 2 to 24 hours, and even more preferably 5 to 12 hours. Drying is preferably carried out in air or nitrogen, and more preferably in air.

[0034] The dried product is preferably further calcined to oxidize or thermally decompose unnecessary substances such as nitrate radicals that could not be removed by drying, thereby improving catalytic performance.

[0035] The calcination temperature is not particularly limited and may be appropriately selected depending on the type of compound and support used, but is preferably 350 to 700°C, more preferably 400 to 600°C, and even more preferably 450 to 550°C.

[0036] The firing time is preferably 30 minutes to 12 hours, more preferably 1 to 6 hours, and even more preferably 2 to 4 hours.

[0037] The method for producing the catalyst may include, in addition to the steps described above, other steps that are usually carried out in catalyst preparation methods, such as a filtration step.

[0038] The catalyst for producing epoxides of the present invention is a catalyst used in the reaction for producing epoxides from glycols.

[0039] The glycols are not particularly limited as long as they have a glycol structure in which one hydrogen atom in each of two adjacent methylene groups is substituted with a hydroxyl group, such as 1,2-glycol. Examples include alkylene glycols such as ethylene glycol (1,2-ethanediol), propylene glycol (1,2-propanediol), 1,2-butanediol, 1,2-pentanediol, and 1,2-hexanediol, and glycols having a phenyl group such as styrene glycol. Among these, the glycols are preferably linear hydrocarbons.

[0040] When the glycol is a straight-chain hydrocarbon, the number of carbon atoms is preferably 2 to 8, more preferably 2 to 6, and even more preferably 3 to 5, in terms of obtaining a high epoxide yield.

[0041] When the catalyst for producing epoxides of the present invention is used, the glycols undergo a dehydration reaction from two adjacent hydroxyl groups to be cyclized to produce epoxides.

[0042] 2. Epoxide manufacturing method The use of the catalyst for producing epoxides of the present invention allows epoxides to be efficiently produced from glycols. Such a method for producing epoxides, which includes a reaction step of producing epoxides from glycols in the presence of a catalyst, and which contains an alkali metal and at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum, also constitutes one aspect of the present invention.

[0043] The reaction step is preferably a gas-phase dehydration reaction. The gas-phase dehydration reaction is a reaction in which glycols are dehydrated by a gas-phase catalytic reaction between glycols and a catalyst. Epoxides are produced by this reaction. The reaction format for the gas-phase dehydration reaction may be any of a fixed bed, a moving bed, a fluidized bed, etc., but a solid bed flow type is preferred.

[0044] When the reaction system is a fixed-bed flow system, the glycols used as raw materials are supplied in a gaseous state. In the step of reacting the glycols in the presence of the catalyst, the gaseous glycols may be supplied to a reactor and brought into contact with the catalyst. The gaseous glycols can be obtained by heating liquid glycols in a vaporizer.

[0045] The reaction step may be carried out under a flow of an inert gas. Specifically, for example, the reaction step may be carried out by supplying a raw material gas containing a gaseous glycol and an inert gas to a reactor. Examples of the inert gas include nitrogen gas (N), argon gas, helium gas, and a mixture thereof, which are inert gases that are not used in the reaction. The content of the inert gas in the raw material gas can be adjusted appropriately from the viewpoint of the desired yield.

[0046] The reaction temperature in the above reaction step is preferably 300°C or higher, more preferably 300 to 500°C, even more preferably 350 to 450°C, and most preferably 380 to 420°C. The "reaction temperature" in the reaction step refers to the average temperature of the catalyst layer while the raw material gas is flowing through it.

[0047] The reaction pressure in the above reaction step can be any of reduced pressure, normal pressure, and increased pressure, but it is usually preferable to carry out the reaction in an atmosphere of normal pressure to slightly increased pressure, specifically, for example, 0.1 to 10 MPa, more preferably 0.1 to 1 MPa, and even more preferably 0.1 to 0.8 MPa.

[0048] In the above reaction step, the ratio (W / F) of the mass W (kg) of the catalyst to the gas flow rate F (mol / sec) of the glycols is preferably 5 kg sec / mol or more and 600 kg sec / mol or less, more preferably 10 kg sec / mol or more and 400 kg sec / mol or less, and even more preferably 20 kg sec / mol or more and 150 kg sec / mol or less, in order to obtain a sufficient epoxide yield in a practical catalytic reactor size.

[0049] The method for producing epoxides may include, in addition to the reaction step, known steps that are usually carried out in methods for producing epoxides, such as a concentration step, a purification step, and a catalyst regeneration step.

[0050] As described above, by using the catalyst for producing epoxides of the present invention, epoxides can be produced efficiently from glycols. [Example]

[0051] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0052] Example 1 Cesium nitrate (CsNO3, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the Cs source, boric acid (H3BO3, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the B source, and silica (SiO2, manufactured by Fuji Silysia Chemical Industries, Ltd., CAriACT Q-10) was used as the support. Each raw material was weighed so that the elemental ratios of the first and second components, when the silica support was taken as 1, were the values ​​shown in Table 1. The weighed cesium nitrate and boric acid were added to 20 mL of distilled water and dissolved. While the support was heated under an incandescent lamp, an aqueous solution of boric acid and cesium nitrate was added dropwise using a dropper. After the entire aqueous solution was added dropwise and the water evaporated, the support was dried at 110 °C overnight. The dried powder was calcined at 500 °C for 3 hours to obtain Catalyst A. The R value and loading rate of Catalyst A were as shown in Table 1.

[0053] Example 2 Catalyst B was obtained in the same manner as in Example 1, except that aluminum nitrate nonahydrate (Al(NO3)3·9H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the Al raw material instead of the B raw material, and the composition was adjusted to that shown in Table 1.

[0054] Example 3 Catalyst C was obtained in the same manner as in Example 1, except that zirconium oxynitrate dihydrate (ZrO(NO3)2·2H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the Zr raw material instead of raw material B, and the composition was adjusted to that shown in Table 1.

[0055] Example 4 Catalyst D was obtained in the same manner as in Example 1, except that potassium nitrate (KNO3, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the K raw material instead of the Cs raw material, and the composition was as shown in Table 1.

[0056] (Comparative Example 1) Catalyst E was prepared in the same manner as in Example 1, except that ammonium niobium oxalate n-hydrate (NH4[NbO(C2O4)2(H2O)]·nH2O, Catalysis Society Reference Catalyst JRC-NBO-3AO) was used as the Nb source instead of raw material B, to obtain the composition shown in Table 1. The loading rate was calculated using Nb2O5 as the Nb oxide.

[0057] (Comparative Example 2) Instead of the B raw material, ammonium metatungstate n-hydrate ((NH4)6H2W 12 O 40 Catalyst F was prepared in the same manner as in Example 1, except that W was used as the oxide of W (WO3) to obtain the composition shown in Table 1. The loading rate was calculated using WO3 as the oxide of W.

[0058] (Comparative Example 3) Catalyst G was prepared in the same manner as in Example 1, except that cesium chloride (CsCl, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the Cs raw material and diammonium hydrogen phosphate ((NH4)2HPO4, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the P raw material, so as to have the composition shown in Table 1. The loading rate was calculated using P2O5 as the P oxide.

[0059] Example 5 Catalyst H was prepared in the same manner as in Example 2 so as to have the composition shown in Table 1.

[0060] Example 6 Catalyst I was prepared in the same manner as in Example 3 so as to have the composition shown in Table 1.

[0061] Example 7 Catalyst J was obtained in the same manner as in Example 1, except that lanthanum nitrate hexahydrate (La(NO3)3·6H2O, manufactured by Kishida Chemical Co., Ltd.) was used as the La raw material instead of raw material B, and the composition was adjusted to that shown in Table 1.

[0062] [Table 1]

[0063] Using the catalysts of the above Examples and Comparative Examples, the catalysts were evaluated according to the following evaluation methods 1 to 6.

[0064] (Evaluation 1) Catalyst performance evaluation 0.5 g of each catalyst was packed into a glass fixed-bed flow reactor, and nitrogen was introduced at 30 cm 3 The catalyst was flowed at a flow rate of 1.8 g / min and pre-treated at 400°C for 1 hour. After pre-treatment, 1,2-propanediol was fed at 1.8 g / h at 400°C. The W / F (weight of catalyst / molar flow rate of fed 1,2-propanediol) during the reaction was 76.1 kg·sec / mol. The reactor outlet gas was introduced into a trap cooled with dry ice acetone, where unreacted raw materials and products were collected. The components collected in the trap were quantitatively analyzed by GC-FID. Gaseous products not collected by the trap were introduced into GC-TCD for analysis. The measurement conditions for GC-FID and GC-TCD are shown below. From these analysis results, the 1,2-propanediol conversion, propylene oxide selectivity (PO selectivity), and propylene oxide yield (PO yield) were calculated using the following formula. The reaction continued for 5 hours, and the reaction results were measured every hour. The average of the measurements from hours 1 to 5 was used as the reaction results.

[0065] (GC-FID measurement conditions) Equipment: Shimadzu GC-14B Column: InertCap WAT (30m) Column oven temperature: 40-240°C, temperature increase 10°C / min Carrier gas: hydrogen Gas flow rate: 20 mL / min (GC-TCD measurement conditions) Equipment: Shimadzu GC-8A Column: VZ-7 (6 m) Column oven temperature: 40°C Carrier gas: hydrogen Gas flow rate: 20 mL / min

[0066] Conversion rate (%) = 100 - (outlet 1,2-propanediol molar flow rate / inlet 1,2-propanediol molar flow rate) x 100 Selectivity (%)=100×[(molar flow rate of product×number of carbon atoms in product) / (molar flow rate of converted 1,2-propanediol×3)] Yield (%) = Conversion (%) × Selectivity (%) / 100

[0067] FIG. 1 is a graph showing the conversion rate, PO selectivity, and PO yield when the catalysts of Examples 1 to 7 and Comparative Examples 1 to 3 were used, respectively. FIG. 1 shows that in the reaction of producing propylene oxide from 1,2-propanediol, the use of catalysts A to D and H to J of the examples, which contain an alkali metal and boron, aluminum, zirconium, or lanthanum, results in a higher propylene oxide yield than the use of catalysts E to G of the comparative examples, which contain an alkali metal and niobium, tungsten, or phosphorus. It was also found that the propylene oxide yield was higher when a catalyst containing cesium was used than when a catalyst containing potassium was used.

[0068] [Table 2]

[0069] (Examples 8 to 10) Catalysts K to M were prepared in the same manner as in Example 1, except that the amounts of the Cs raw material and the B raw material were changed so as to obtain the compositions shown in Table 2.

[0070] FIG. 2 also shows the conversion, PO selectivity, and PO yield versus the loading rate for catalysts A, K, L, and M, which have the same R value, as well as quadratic approximation curves for each plot. The catalysts shown in Figure 2 contain cesium as the first component and boron as the second component, and therefore all catalysts have high PO yields. However, it was found that the PO yield was sufficiently high at a loading rate of 9.8%, and was even higher at loading rates of 15% or higher.

[0071] [Table 3]

[0072] Examples 11 to 14 Catalysts N to Q were prepared in the same manner as in Example 1, except that the amount of the Cs raw material was changed so as to obtain the compositions shown in Table 3.

[0073] Figure 3 shows the conversion, PO selectivity, and PO yield versus R value for catalysts A, N, O, P, and Q, which contain cesium and boron and have different R values, as well as the quadratic approximation curves for each plot. Figure 3 shows that the PO yield is high when the R value is 0.9 or less, and that the PO yield is even higher when the R value is in the range of 0.35 to 0.55.

[0074] (Evaluation 2) Durability evaluation To evaluate the durability of the catalyst, the amount of catalyst A, H, and I used was reduced from 0.5 g to 0.15 g, and nitrogen was introduced at 30 cm3 in the same manner as in Evaluation 1. 3 The catalyst was pretreated at 400°C for 1 hour with a flow rate of 1.8 g / hour of 1,2-propanediol. After pretreatment, 1,2-propanediol was fed at 400°C at a rate of 1.8 g / hour, and the catalytic activity was evaluated 1 hour and 5 hours after the start of the reaction. The W / F (catalyst mass / feed 1,2-propanediol molar flow rate) was 22.8 kg·sec / mol, and the GC-FID and GC-TCD measurement conditions were the same as in Evaluation 1.

[0075] The catalytic activity was evaluated by the ratio k(5h) / k(0h) of the reaction rate constants k(0h) and k(5h) calculated at the beginning of the reaction and after 5 hours, assuming that the reaction of propylene oxide from 1,2-propanediol is a first-order reaction of the partial pressure of 1,2-propanediol. Here, the conversion rates at the beginning of the reaction and after 5 hours are x0 and x5, respectively, and the change in the number of molecules due to the progress of the reaction is ignored. Furthermore, w is the catalyst weight (kg), F N2 is the molar flow rate of N2 supplied to the inlet (mol / sec), F PG is the molar flow rate (mol / sec) of 1,2-propanediol fed to the inlet, P t is the reaction pressure (Pa).

[0076]

number

[0077]

number

[0078] The catalytic activity after 5 hours, when the initial catalytic activity k(0 h) calculated from the above formula is set to 1.0, is shown in Figure 4. Figure 4 shows that the catalysts of the examples were able to maintain catalytic activity of 0.5 or more of the initial catalytic activity even after 5 hours of reaction, demonstrating excellent durability.

[0079] (Evaluation 3) Evaluation of reaction performance depending on reaction temperature 0.5 g of catalyst A was packed into a glass fixed-bed flow reactor, and nitrogen was introduced at a rate of 30 cm 3 The catalyst was flowed at a flow rate of 1.8 g / min and pretreatment was carried out at 400 °C for 1 hour. Next, the reaction temperature was increased from 350 °C to 430 °C while feeding 1,2-propanediol at a rate of 1.8 g / h. The W / F (weight of catalyst / molar flow rate of fed 1,2-propanediol) at this time was 76.1 kg·sec / mol. The analysis was performed in the same manner as in Evaluation Example 1, and the 1,2-propanediol conversion, propylene oxide selectivity (PO selectivity), and propylene oxide (PO yield) were calculated. The conversion, PO selectivity, and PO yield versus each reaction temperature, as well as the quadratic approximation curves of each plot, are shown in Figure 5.

[0080] From FIG. 5, it was found that the PO yield was higher when the reaction temperature was 370° C. or higher, preferably 400° C. or higher.

[0081] (Evaluation 4) Epoxide production from 1,2-butanediol 0.5 g of catalyst B (Example 2) was packed into a glass fixed-bed flow reactor, and nitrogen was introduced at 30 cm 3 The catalyst was flowed at a flow rate of 1.44 g / min and pre-treated at 400°C for 1 hour. After pre-treatment, 1,2-butanediol was fed at 1.44 g / h at 400°C. The W / F (weight of catalyst / molar flow rate of fed 1,2-butanediol) was 112.65 kg·sec / mol. In the same manner as in Evaluation Example 1, the 1,2-butanediol conversion, 1,2-epoxybutane selectivity (1,2-EB selectivity), and 1,2-epoxybutane yield (1,2-EB yield) were calculated using the following formulas. Conversion rate (%) = 100 - (outlet 1,2-butanediol molar flow rate / inlet 1,2-butanediol molar flow rate) x 100 Selectivity (%)=100×[(molar flow rate of product×number of carbon atoms in product) / (molar flow rate of converted 1,2-butanediol×4)] The results are shown in Figure 6. In Figure 6, the conversion of the raw material having 4 linear carbon atoms is the 1,2-butanediol conversion, the selectivity is the 1,2-EB selectivity, and the yield is the 1,2-EB yield.

[0082] (Evaluation 5) Epoxide production from ethylene glycol 0.3 g of Catalyst A (Example 1) was packed into a glass fixed-bed flow reactor, and 74.5 cm of nitrogen was added. 3 The catalyst was flowed at a flow rate of 1.47 g / min and pre-treated at 400°C for 1 hour. After pre-treatment, ethylene glycol was fed at 400°C at a rate of 1.47 g / h. The W / F (weight of catalyst / molar flow rate of fed ethylene glycol) was 45.6 kg·sec / mol. The gas at the reactor outlet was analyzed in the same manner as in Evaluation Example 1. From the analysis results, the ethylene glycol conversion rate, ethylene oxide selectivity (EO selectivity), and ethylene oxide yield (EO yield) were calculated using the following formulas. Conversion rate (%) = 100 - (outlet ethylene glycol molar flow rate / inlet ethylene glycol molar flow rate) x 100 Selectivity (%) = 100 × [(molar flow rate of product × carbon number of product) / (molar flow rate of converted ethylene glycol × 2)] The results are shown in Figure 6. In Figure 6, the conversion of the raw material having two linear carbon atoms is the ethylene glycol conversion, the selectivity is the EO selectivity, and the yield is the EO yield.

[0083] (Evaluation 6) Epoxide production from 1,2-pentanediol 0.2 g of catalyst B (Example 2) was packed into a glass fixed-bed flow reactor, and nitrogen was introduced at 30 cm 3The catalyst was flowed at a flow rate of 1.4 g / min and pre-treated at 400°C for 1 hour. After pre-treatment, 1,2-pentanediol was fed at 1.4 g / h at 400°C. The W / F (weight of catalyst / molar flow rate of fed 1,2-pentanediol) was 53.6 kg·sec / mol. In the same manner as in Evaluation Example 1, the 1,2-pentanediol conversion, 1,2-epoxypentane selectivity (1,2-EP selectivity), and 1,2-epoxypentane yield (1,2-EP yield) were calculated using the following formulas. Conversion rate (%) = 100 - (outlet 1,2-pentanediol molar flow rate / inlet 1,2-pentanediol molar flow rate) x 100 Selectivity (%)=100×[(molar flow rate of product×number of carbon atoms in product) / (molar flow rate of converted 1,2-pentanediol×5)] The results are shown in Figure 6. In Figure 6, the conversion of the raw material having 5 linear carbon atoms is the 1,2-pentanediol conversion, the selectivity is the 1,2-EP selectivity, and the yield is the 1,2-EP yield.

[0084] From FIG. 6, it was found that, when the catalyst of the present invention is used, good reaction results are obtained even when the linear carbon number of the raw material glycol is 2, and even better reaction results are obtained when the linear carbon number is 3 or more, and the highest epoxide yield is obtained when the linear carbon number is 5.

Claims

1. A catalyst used in a reaction for producing epoxides from glycols, comprising: The catalyst for producing epoxides comprises a first component consisting of an alkali metal and a second component consisting of at least one element selected from the group consisting of boron, aluminum, zirconium and lanthanum.

2. 2. The catalyst for producing epoxides according to claim 1, wherein the alkali metal comprises potassium or cesium.

3. 3. The catalyst for producing epoxides according to claim 1, wherein the value R, which is the ratio of the number of moles of the second component to the number of moles of the first component, is 0.1 to 1.

5.

4. 3. The catalyst for producing epoxides according to claim 1, wherein the first component and the second component are supported on a carrier at a support rate of 2 to 47 mass %.

5. 1. A method for producing epoxides, comprising: The production method includes a reaction step of producing epoxides from glycols in the presence of a catalyst, The catalyst contains an alkali metal and at least one element selected from the group consisting of boron, aluminum, zirconium, and lanthanum. A method for producing epoxides, comprising:

6. 6. The method for producing epoxides according to claim 5, wherein the reaction in the reaction step is a gas-phase dehydration reaction.

7. 7. The method for producing epoxides according to claim 5, wherein in the reaction step, a ratio W / F of a mass W (kg) of the catalyst to a gas flow rate F (mol / sec) of the glycols is 5 kg sec / mol or more and 600 kg sec / mol or less.

8. 7. The method for producing epoxides according to claim 5, wherein the reaction temperature in the reaction step is 300° C. or higher.

9. 7. The method for producing epoxides according to claim 5, wherein the glycol is a straight-chain hydrocarbon.

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