Method for producing carbon monoxide and production device

Abstract

The present application provides a method for producing carbon monoxide, which includes a step of generating carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst in which the total pore volume of pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for producing carbon monoxide and a production apparatus. BACKGROUND

[0002] In the past, as a method for producing carbon monoxide, there are known a method of producing carbon monoxide by steam reforming of natural gas, a method of producing carbon monoxide by contacting oxygen with a light hydrocarbon in the presence of a partial oxidation catalyst, a method of producing carbon monoxide by decomposing formic acid, and the like. Among these, the method of producing carbon monoxide by decomposing formic acid is advantageous in that carbon monoxide can be obtained at a high selectivity. As the method of producing carbon monoxide by decomposing formic acid, there are known a method of using a mineral acid, a method of using a solid acid catalyst, and the like. Among these, the method of using a solid acid catalyst is promising as a method capable of producing carbon monoxide at a high conversion rate. For example, in Patent Literature 1 described below, there is disclosed a method of reducing the hydrogen concentration in carbon monoxide by performing a purification process using a palladium catalyst or the like on carbon monoxide generated by decomposing formic acid using a solid acid catalyst.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Korean Patent Publication No. 2016-0173781 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] However, the method described in the above Patent Literature 1 has the following problem.

[0008] That is, in the method described in the above Patent Literature 1, in order to reduce the hydrogen concentration, a purification process using a palladium catalyst or the like is performed on carbon monoxide generated by the decomposition of formic acid. Therefore, the method described in the above Patent Literature 1 has room for improvement in terms of efficiently and at a low cost producing high-purity carbon monoxide.

[0009] Therefore, there is a demand for a method for producing carbon monoxide that can sufficiently reduce the hydrogen concentration in produced carbon monoxide without performing a purification process for removing hydrogen.

[0010] Therefore, an object of the present application is to provide a method for producing carbon monoxide that can sufficiently reduce the hydrogen concentration in produced carbon monoxide without performing a purification process for removing hydrogen and a production apparatus.

[0011] MEANS FOR SOLVING THE PROBLEMS

[0012] The present inventors have made intensive studies in order to solve the above problem. Specifically, the present inventors have made studies focusing on the total pore volume of the solid acid catalyst. Generally, a solid acid has pores that adsorb molecules. For example, a zeolite is a solid acid that includes pores having a pore diameter of 2 nm or less, i.e., a microporous solid acid, and adsorbs molecules that are smaller than the diameter thereof. Also, a catalyst has a porous structure, and thus active sites are present mostly in the pores, and react with raw material molecules through contact with the active sites. Therefore, generally, the larger the total pore volume, the greater the amount of raw material molecules adsorbed to the solid acid, and thus the present inventors have predicted that by increasing the total pore volume, the raw material is effectively decomposed, as a result of which the selectivity of the raw material to carbon monoxide is improved, and the concentration of impurities, i.e., hydrogen, in the manufactured carbon monoxide is also reduced. However, surprisingly, it has been found that the smaller the total pore volume of the solid acid catalyst, the lower the hydrogen concentration in the manufactured carbon monoxide. Therefore, as a result of further diligent studies based on such findings, the present inventors have found that the above problem can be solved by the following invention.

[0013] That is, one aspect of the present invention is a method for producing carbon monoxide, which includes a step of producing carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst, in which the total pore volume of pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

[0014] According to the present invention, in the solid acid catalyst, compared to the case where the total pore volume of pores having a pore diameter of 2 nm or less exceeds 0.23 cm 3 / g, the hydrogen concentration in the manufactured carbon monoxide can be sufficiently reduced without performing a purification step for removing hydrogen. Therefore, according to the method for producing carbon monoxide of the present invention, high-purity carbon monoxide can be efficiently and at low cost.

[0015] Alternatively, according to the present invention, in the solid acid catalyst, compared to the case where the total pore volume of pores having a pore diameter of 2 nm or less exceeds 0.23 cm 3 / g, the conversion rate of the raw material can be improved. Therefore, according to the method for producing carbon monoxide of the present invention, carbon monoxide can be efficiently produced.

[0016] In the above method for producing carbon monoxide, in the solid acid catalyst, the total pore volume of pores having a pore diameter of 2 nm or less is preferably 0.20 cm 3 / g or less.

[0017] In this case, the conversion rate of the raw material is further improved, and the hydrogen concentration in the manufactured carbon monoxide can be more sufficiently reduced without performing a purification step for removing hydrogen.

[0018] In the above method for producing carbon monoxide, the total pore volume of the pores having a pore diameter of 2 nm or less in the solid acid catalyst is more preferably 0.19 cm 3 / g or less.

[0019] In this case, the conversion rate of the raw material is improved, and the hydrogen concentration in the produced carbon monoxide can be more sufficiently reduced without performing a purification step for removing hydrogen.

[0020] In the above method for producing carbon monoxide, the solid acid catalyst is, for example, a proton-type zeolite.

[0021] In the above method for producing carbon monoxide, the Si / Al atomic ratio of the proton-type zeolite is preferably 1 to 200.

[0022] In this case, the catalytic activity of the zeolite can be further improved, and the conversion rate of the raw material can be further improved.

[0023] In the above method for producing carbon monoxide, the decomposition reaction of the raw material is preferably performed at 100 to 300°C.

[0024] In this case, there is a tendency that the hydrogen concentration in the produced carbon monoxide can be further sufficiently reduced and the decomposition reaction can be effectively performed.

[0025] Another aspect of the present application is a device for producing carbon monoxide, which produces carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst, and includes a reactor that houses the solid acid catalyst and produces carbon monoxide by the decomposition reaction of the raw material in the presence of the solid acid catalyst, in which the total pore volume of the pores having a pore diameter of 2 nm or less in the solid acid catalyst is 0.23 cm 3 / g or less.

[0026] According to the device for producing carbon monoxide, if carbon monoxide is produced by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst in a reactor, the hydrogen concentration in the produced carbon monoxide can be sufficiently reduced without performing a purification step for removing hydrogen, as compared with a case where the total pore volume of the pores having a pore diameter of 2 nm or less exceeds 0.23 cm 3 / g. Therefore, according to the device for producing carbon monoxide of the present application, high-purity carbon monoxide can be efficiently and at a low cost.

[0027] Alternatively, according to the above carbon monoxide production apparatus, if carbon monoxide is produced by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst in a reactor, the total pore volume of pores having a pore diameter of 2 nm or less in the solid acid catalyst is more than 0.23 cm 3 / g, the conversion rate of the raw material can be improved. Therefore, according to the carbon monoxide production apparatus of the present application, carbon monoxide can be efficiently produced.

[0028] In the above carbon monoxide production apparatus, the total pore volume of pores having a pore diameter of 2 nm or less in the solid acid catalyst is preferably 0.20 cm 3 / g or less.

[0029] In this case, the conversion rate of the raw material is further improved, and the hydrogen concentration in the produced carbon monoxide can be more sufficiently reduced without performing a purification process for removing hydrogen.

[0030] Effects of the Invention

[0031] According to the present application, a carbon monoxide production method and a carbon monoxide production apparatus in which the hydrogen concentration in produced carbon monoxide can be sufficiently reduced without performing a purification process for removing hydrogen can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a schematic view showing an embodiment of a carbon monoxide production apparatus of the present application.

[0033] Figure 2 is a graph showing the relationship between the hydrogen concentration and the total pore volume of pores having a pore diameter of 2 nm or less in Examples 1 to 3 and Comparative Example 1.

[0034] Figure 3 is a graph showing the relationship between the conversion rate of a raw material and the total pore volume of pores having a pore diameter of 2 nm or less in Examples 1 to 3 and Comparative Example 1. DETAILED DESCRIPTION

[0035] Hereinafter, an embodiment of the present application will be described in detail. However, the present application is not limited to the following embodiment.

[0036] The carbon monoxide production method of the present application includes a step of producing carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst. As the solid acid catalyst, a solid acid catalyst having a total pore volume of pores having a pore diameter of 2 nm or less (hereinafter, also referred to as "micropores") of 0.23 cm 3 / g or less. The carbon monoxide production method of the present application can be implemented, for example, by a carbon monoxide production device provided with a reactor that houses the above-mentioned solid acid catalyst and produces carbon monoxide by a decomposition reaction of a raw material in the presence of the solid acid catalyst.

[0037] (Solid acid catalyst)

[0038] The solid acid catalyst is not particularly limited, and as the solid acid catalyst, for example, a proton-type zeolite is preferably used. As the proton-type zeolite, zeolites such as mordenite, ZSM-5, beta type, Y type, and US-Y type can be mentioned. As the proton-type zeolite catalyst, for example, a high-silica zeolite catalyst manufactured by TOSOH CORPORATION or the like can be used.

[0039] In the solid acid catalyst, the total pore volume of the micropores is 0.23 cm 3 / g or less. In the solid acid catalyst, if the total pore volume of the micropores is 0.23 cm 3 / g or less, the hydrogen concentration in the produced carbon monoxide can be sufficiently reduced without performing a purification process for removing hydrogen, compared to a case where a solid acid catalyst having a total pore volume of micropores exceeding 0.23 cm 3 / g is used. Alternatively, in the solid acid catalyst, the raw material conversion rate can be improved compared to a case where the total pore volume of micropores having a pore diameter of 2 nm or less exceeds 0.23 cm 3 / g. Therefore, according to the carbon monoxide production method of the present application, carbon monoxide can be efficiently produced. From the viewpoint of improving the raw material conversion rate and further sufficiently reducing the hydrogen concentration in the produced carbon monoxide without performing a purification process for removing hydrogen, the total pore volume of the micropores of the solid acid catalyst is preferably 0.20 cm 3 / g or less, more preferably 0.19 cm 3 / g or less, and further more preferably 0.18 cm 3 / g or less, and particularly preferably 0.15 cm 3 / g or less. However, in the solid acid catalyst, the total pore volume of the micropores is preferably 0.10 cm 3 / g or more, and more preferably 0.12 cm 3 / g or more. In the solid acid catalyst, if the total pore volume of the micropores is 0.10 cm 3 / g or more, the decomposition reaction of the raw material is more easily performed, and as a result, there is a tendency to further improve the raw material conversion rate.

[0040] The pore diameter is a value dp obtained by analyzing the measurement results obtained under the following conditions by the SF method using BELSORP-MAX (manufactured by MicrotracBEL Corp.) as an analysis device and BELMaster (manufactured by MicrotracBEL Corp.) as an analysis software.

[0041] (Conditions)

[0042] Measurement temperature: -196°C

[0043] Adsorbate: nitrogen

[0044] Equilibrium adsorption time: 300 seconds

[0045] Pre-treatment conditions of the solid acid catalyst: heat treatment under vacuum (pump specifications: limit pressure 6.7 x 10 -7 Pa) (350°C, 5 h)

[0046] The total pore volume of the pores having a pore diameter of 2 nm or less is a cumulative value ∑Vp of the pore volumes calculated by analyzing the pore diameter by the SF method. The pore diameter dp calculated as described above is a value of 2 nm or less.

[0047] The Si / Al atomic ratio of the proton-type zeolite used as the solid acid catalyst is not particularly limited, and is preferably 1 or more, and more preferably 5 or more. If the Si / Al atomic ratio is 1 or more, there is a tendency to further improve the catalytic activity of the zeolite and improve the conversion rate of the raw material. The Si / Al atomic ratio is preferably 200 or less, more preferably 150 or less, still more preferably 100 or less, and particularly preferably 50 or less. If the Si / Al atomic ratio is 200 or less, there is a tendency to further improve the catalytic activity of the zeolite and improve the conversion rate of the raw material. Therefore, from the viewpoint of improving the conversion rate of the raw material, the Si / Al atomic ratio of the proton-type zeolite is preferably 1 to 200. In particular, in the solid acid catalyst, in the case where the total pore volume of the micropores is less than 0.19 cm 3 / g, the Si / Al atomic ratio is preferably 5 to 100, more preferably 5 to 50, still more preferably 5 to 30, and particularly preferably 5 to 20. In the solid acid catalyst, in the case where the total pore volume of the micropores is less than 0.19 cm3 / g, if the Si / Al atomic ratio is 5 to 100, the conversion rate of the raw material is significantly improved.

[0048] In addition, the Si / Al atomic ratio can be obtained by measurement based on the solid NMR method.

[0049] (Raw material)

[0050] As the raw material, formic acid and alkyl formate can be given. These can be used alone or also in the form of a mixture. As the alkyl formate, for example, methyl formate and ethyl formate can be given.

[0051] (decomposition reaction)

[0052] The decomposition reaction of the raw material is performed by bringing the raw material into contact with the solid acid catalyst and heating to decompose it. Alternatively, the decomposition reaction of the raw material can also be performed by bringing the raw material into contact with the solid acid catalyst which is preliminarily modified with a mineral acid and heating to decompose it. The contact of the raw material with the solid acid catalyst can be performed, for example, by bringing a gas or a liquid containing the raw material into contact with the solid acid catalyst. In the case where a gas containing the raw material is brought into contact with the solid acid catalyst, a gas containing a vapor of the raw material is generated from a solution containing the raw material using a vaporizer or the like, which can be supplied to the solid acid catalyst to be contacted. The contact of the raw material with the solid acid catalyst is preferably performed by bringing a gas containing the raw material into contact with the solid acid catalyst. In this case, there is a tendency to improve the efficiency of the decomposition reaction. In the case where a liquid containing the raw material is used, the concentration of the raw material in the liquid is not particularly limited, and from the viewpoint of energy efficiency, it is preferably 40% by mass or more based on the mass of the solution (100% by mass). As the liquid containing the raw material, for example, an aqueous formic acid solution can be given.

[0053] As the reactor, a reaction vessel or a reaction column packed with a catalyst can be used. In the case where a reaction vessel is used as the reactor, the catalyst and the raw material are charged into the reaction vessel and heated, whereby carbon monoxide can be generated. In the case where a reaction column packed with a catalyst is used as the reactor, for example, a vapor of the raw material is passed through the catalyst packed in the reaction column and heated, whereby carbon monoxide can be generated. If the reaction efficiency is considered, it is preferable to use a reaction column packed with a catalyst as the reactor. The reaction column can be one or a plurality of reaction columns can be connected. The reactor composed of a plurality of reaction columns is advantageous in terms of suppression of the deviation of the flow rate distribution in the reactor and securing of the heat transfer area for heating. In the case where a gas or a liquid containing the raw material is continuously supplied to the reactor, the reactor generally has an inlet and an outlet for supplying or discharging the gas or the liquid, which are connected to the flow path outside.

[0054] The reactor is composed of, for example, a nonmetallic material such as carbon. The reactor formed of a nonmetallic material is less likely to be corroded by the raw material and carbon monoxide and is less likely to be affected on the reaction. In the case where the temperature at which the decomposition reaction of the raw material is performed (reaction temperature) is a relatively low temperature (for example, 100 to 200°C), as the reactor, a reactor having a surface treated by glass lining can also be used.

[0055] The space velocity (SV) of the gas containing the raw material (hereinafter, referred to as "raw material gas") is not particularly limited, and is preferably 1000 [1 / h] or less. From the viewpoint of further improving the conversion rate of the raw material, the SV is more preferably 280 [1 / h] or less, and particularly preferably 240 [1 / h] or less. However, the SV is preferably 0.1 [1 / h] or more, more preferably 100 [1 / h] or more, and particularly preferably 200 [1 / h] or more.

[0056] The space velocity of the raw material gas refers to a value measured by a standard conversion reference. The space velocity of the raw material gas can be calculated, for example, from the supply rate (g / h) of the raw material gas and the volume of the solid acid catalyst, according to the following formula.

[0057] Space velocity of raw material gas [1 / h]

[0058] = Supply rate of raw material gas (g / h) x 0.01

[0059] x Concentration of at least one of formic acid or formic acid alkyl ester in raw material gas (wt%)

[0060] ÷ Molecular weight of formic acid or formic acid alkyl ester (raw material) (g / mol)

[0061] x Standard state volume 22.4 (NL / mol)

[0062] ÷ Volume of solid acid catalyst (L)

[0063] In addition, in the case where the raw material gas is a gas obtained by gasifying a liquid containing the raw material (hereinafter, referred to as "raw material liquid"), the "concentration of at least one of formic acid or formic acid alkyl ester in the raw material liquid" is recorded as the "concentration of at least one of formic acid or formic acid alkyl ester in the raw material gas".

[0064] The reaction temperature is a temperature at which the decomposition of the raw material can be performed, and is preferably 100 to 300°C, and more preferably 100 to 200°C. By setting the reaction temperature to 100 to 300°C, there is a tendency that the reaction can be effectively performed while the hydrogen concentration in the manufactured carbon monoxide is more sufficiently reduced and / or the generation of by-products such as hydrogen is suppressed. As the reactor, for example, a reaction column filled with a catalyst is used, and in the case where a heater is provided around the solid acid catalyst, the set temperature of the heater is used as the reaction temperature. The decomposition reaction of the raw material is generally performed in a state where the catalyst, the raw material, or both are heated to the above-mentioned temperature.

[0065] The generated carbon monoxide sometimes contains water and extremely small amounts of hydrogen, carbon dioxide, and methane as byproducts. Therefore, the carbon monoxide production method can further include a step of removing unreacted raw material and byproducts from the carbon monoxide taken out from the reactor and a step of removing water from the carbon monoxide. The raw material and byproducts can be removed by a general cleaning method, and thus carbon monoxide with high purity can be obtained. The raw material and carbon dioxide can be easily removed by, for example, caustic soda. The water can be removed by, for example, cooling and adsorption to a dehydration material. By these steps, the purity of the carbon monoxide after removal of water, raw material, and byproducts can also be 99.99% or more. Such carbon monoxide with high purity can be used for various uses including the field of semiconductor production.

[0066] Figure 1 is a schematic view showing an embodiment of a carbon monoxide production apparatus of the present application. As shown in Figure 1 the carbon monoxide production apparatus 10 of the present application is provided with a reactor 1 and a solid acid catalyst 2 housed in the reactor 1. As the reactor 1, the above-described reactor can be used, and as the solid acid catalyst 2, the above-described solid acid catalyst can be used. The reactor 1 has an inlet la and an outlet lb for supplying or discharging gas or liquid. On the outside of the reactor 1, a flow path 3 for supplying a raw material of at least one of formic acid or formic acid alkyl ester is connected to the inlet la, and a flow path 4 for discharging gas or liquid is connected to the outlet lb. The carbon monoxide production apparatus 10 can further be provided with a heating device (not shown) for heating the solid acid catalyst 2, the raw material, or both, a device (not shown) for removing unreacted raw material and byproducts from the product containing carbon monoxide, and a device (not shown) for removing water from the product, as needed.

[0067] In the carbon monoxide production apparatus 10, the raw material is supplied to the reactor 1 through the inlet la via the flow path 3 and passes through the solid acid catalyst 2. At this time, carbon monoxide is generated by a decomposition reaction of the raw material in the presence of the solid acid catalyst. The product containing carbon monoxide is discharged from the outlet lb of the reactor 1 via the flow path 4. In this way, carbon monoxide is produced.

[0068] In addition, the present application is outlined as follows.

[0069] [1] A carbon monoxide production method including a step of generating carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or formic acid alkyl ester in the presence of a solid acid catalyst in which the total pore volume of pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

[0070] [2] The carbon monoxide production method according to [1], in which

[0071] In the solid acid catalyst, the total pore volume of the pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

[0072] [3] The method for producing carbon monoxide according to [2], wherein

[0073] In the solid acid catalyst, the total pore volume of the pores having a pore diameter of 2 nm or less is 0.19 cm 3 / g or less.

[0074] [4] The method for producing carbon monoxide according to any one of [1] to [3], wherein

[0075] The solid acid catalyst is a proton-type zeolite.

[0076] [5] The method for producing carbon monoxide according to [4], wherein

[0077] The Si / Al atomic ratio of the proton-type zeolite is 1 to 200.

[0078] [6] The method for producing carbon monoxide according to any one of [1] to [5], wherein

[0079] The decomposition reaction of the raw material is performed at 100 to 300°C.

[0080] [7] A device for producing carbon monoxide, comprising: generating carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst; a reactor that houses the solid acid catalyst and generates carbon monoxide by a decomposition reaction of the raw material in the presence of the solid acid catalyst; and in the solid acid catalyst, the total pore volume of pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

[0081] [8] The device for producing carbon monoxide according to [7], wherein

[0082] In the solid acid catalyst, the total pore volume of the pores having a pore diameter of 2 nm or less is 0.20 cm 3 / g or less.

[0083] Example

[0084] Hereinafter, the present application will be further concretely described by citing examples. However, the present application is not limited to the following examples.

[0085] (Example 1)

[0086] A column having an inner diameter of 2.5 cm and a length of 25 cm as a reactor was filled with a zeolite catalyst (manufactured by TOSOH CORPORATION, Si / Al atomic ratio: 12, total micropore volume: 0.15 cm 3 / g) in a length of 10 cm as a solid acid catalyst. The amount of the zeolite catalyst used was set to 40 g (49 mL). The column filled with the catalyst was heated from the outside with a heater set to 175°C, and a vapor of formic acid at 120°C generated by passing a formic acid aqueous solution having a concentration of 76% by weight through a vaporizer was fed from one end of the column at a feed rate of 31 g / h. In this way, the vapor of formic acid was brought into contact with the solid acid catalyst, and a decomposition reaction was performed, thereby generating carbon monoxide. At this time, the space velocity of the vapor of formic acid (raw material gas) was 234 [1 / h] on a standard conversion basis.

[0087] Furthermore, the carbon monoxide discharged from the other end of the column was passed through an aqueous caustic soda solution having a concentration of 20% by weight and water in this order. With the aqueous caustic soda solution, a trace amount of carbon dioxide contained in the carbon monoxide was removed. After the carbon monoxide passed through the aqueous caustic soda solution and water was cooled and dried, the amount of hydrogen in the carbon monoxide was quantified by gas chromatography as a detector equipped with a PDD (Pulsed Discharge Detector), and the conversion rate of formic acid (raw material), the selectivity to carbon monoxide, and the hydrogen concentration were calculated from the amount of hydrogen found and the flow rate of carbon monoxide. Furthermore, the rate of increase in the conversion rate based on Example 3 was calculated. The results are shown in Table 1. As shown in Table 1, the conversion rate of formic acid (raw material) was 89%, and the rate of increase in the conversion rate based on Example 3 was 178%. Furthermore, the selectivity to carbon monoxide was 99.99% or more, and the hydrogen concentration was 1.8 ppm.

[0088] In addition, the total micropore volume of the solid acid catalyst was measured using a BELSORP-MAX (manufactured by Microtrac BEL Corp.) as an analysis device under the following conditions.

[0089] (Conditions)

[0090] Measurement temperature: -196°C

[0091] Adsorbate: nitrogen

[0092] Equilibrium adsorption time: 300 seconds

[0093] Pretreatment conditions of the solid acid catalyst: heat treatment under vacuum (pump specifications: limit pressure 6.7 x 10 -7 Pa or less) (350°C, 5 h)

[0094] (Example 2)

[0095] As the solid acid catalyst packed in the column, 39 g (49 mL) of a zeolite catalyst (manufactured by TOSOH CORPORATION, Si / Al atomic ratio: 110, total fine pore volume of micropore: 0.19 cm 3 / g) was used, and otherwise, the reaction was performed in the same manner as in Example 1 to produce carbon monoxide. Also, the conversion rate of formic acid (raw material), the selectivity to carbon monoxide, and the hydrogen concentration were calculated in the same manner as in Example 1. Also, the improvement rate of the conversion rate based on Example 3 was calculated. The results are shown in Table 1. As shown in Table 1, the conversion rate of formic acid (raw material) was 60%, and the improvement rate of the conversion rate based on Example 3 was 88%. Also, the selectivity to carbon monoxide was 99.99% or more, and the hydrogen concentration was 4.9 ppm.

[0096] (Example 3)

[0097] As the solid acid catalyst packed in the column, 34 g (49 mL) of a zeolite catalyst (manufactured by TOSOH CORPORATION, Si / Al atomic ratio: 15, total fine pore volume of micropore: 0.23 cm 3 / g) was used, and otherwise, the reaction was performed in the same manner as in Example 1 to produce carbon monoxide. Also, the conversion rate of formic acid (raw material), the selectivity to carbon monoxide, and the hydrogen concentration were calculated in the same manner as in Example 1. Also, the improvement rate of the conversion rate based on Example 3 was calculated. The results are shown in Table 1. As shown in Table 1, the conversion rate of formic acid (raw material) was 32%, and the improvement rate of the conversion rate based on Example 3 was 0%. Also, the selectivity to carbon monoxide was 99.99% or more, and the hydrogen concentration was 11 ppm.

[0098] (Comparative Example 1)

[0099] As the solid acid catalyst packed in the column, 35 g (49 mL) of a zeolite catalyst (manufactured by TOSOH CORPORATION, Si / Al atomic ratio: 3, total fine pore volume of micropore: 0.25 cm 3 / g) was used, and otherwise, the reaction was performed in the same manner as in Example 1 to produce carbon monoxide. Also, the conversion rate of formic acid (raw material), the selectivity to carbon monoxide, and the hydrogen concentration were calculated in the same manner as in Example 1. Also, the improvement rate of the conversion rate based on Example 3 was calculated. The results are shown in Table 1. As shown in Table 1, the conversion rate of formic acid (raw material) was 21%, and the improvement rate of the conversion rate based on Example 3 was -34%. Also, the selectivity to carbon monoxide was 99.93% or more, and the hydrogen concentration was 644 ppm.

[0100] (Comparative Example 2)

[0101] As the solid acid catalyst filled in the column, 32 g (49 mL) of a zeolite catalyst (manufactured by TOSOH CORPORATION, Si / Al atomic ratio: 3, total micropore volume: 0.24 cm 3 / g), otherwise, the reaction was performed in the same manner as in Example 1 to generate carbon monoxide. Also, the conversion rate of formic acid (raw material), the selectivity to carbon monoxide, and the hydrogen concentration were calculated in the same manner as in Example 1. Also, the rate of increase in the conversion rate based on Example 3 was calculated. The results are shown in Table 1. As shown in Table 1, the conversion rate of formic acid (raw material) was 22%, and the rate of increase in the conversion rate based on Example 3 was -31%. Also, the selectivity to carbon monoxide was 99.99% or more, and the hydrogen concentration was 90 ppm.

[0102] [Table 1]

[0103]

[0104] Figure 2 The relationship between the total micropore volume and the hydrogen concentration in the solid acid catalysts of Examples 1 to 3 or Comparative Example 1 is shown in Table 1 and FIG. 1. From the results shown in Table 1 and FIG. 1, it was confirmed that the hydrogen concentration in carbon monoxide was significantly reduced in Examples 1 to 3 as compared with Comparative Example 1. Figure 2

[0105] Therefore, it was confirmed that if the total micropore volume of the solid acid catalyst was 0.23 cm 3 / g or less, the hydrogen concentration in the manufactured carbon monoxide could be sufficiently reduced without performing the purification process for removing hydrogen as compared with the case where the total micropore volume of the solid acid catalyst exceeded 0.23 cm 3 / g.

[0106] Also, Figure 3 The relationship between the total micropore volume and the conversion rate of raw material in the solid acid catalysts of Examples 1 to 3 or Comparative Examples 1 to 2 is shown in Table 1 and FIG. 2. From the results shown in Table 1 and FIG. 2, it was confirmed that the conversion rate of raw material was significantly higher in Examples 1 to 3 as compared with Comparative Examples 1 to 2. Figure 3

[0107] Therefore, it was confirmed that if the total micropore volume of the solid acid catalyst was 0.20 cm 3 / g or less, the conversion rate of raw material could be further increased as compared with the case where the total micropore volume of the solid acid catalyst exceeded 0.20 cm 3 / g.

[0108] BRIEF DESCRIPTION OF DRAWINGS

[0109] ​​1 - Reactor, 1a - Inlet, 1b - Outlet, 2 - Solid acid catalyst, 3, 4 - Flow path, 10 - Carbon monoxide manufacturing device

Claims

1. A method for producing carbon monoxide, comprising: a step of generating carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst, In the solid acid catalyst, the total pore volume of the pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

2. The method for producing carbon monoxide according to claim 1, wherein In the solid acid catalyst, the total pore volume of the fine pores is 0.20 cm 3 / g or less.

3. The method for producing carbon monoxide according to claim 2, wherein In the solid acid catalyst, the total pore volume of the fine pores is 0.19 cm 3 / g or less.

4. The method for producing carbon monoxide according to claim 1, wherein the solid acid catalyst is a proton-type zeolite.

5. The method for producing carbon monoxide according to claim 4, wherein the Si / Al atomic ratio of the proton-type zeolite is 1 to 200.

6. The method for producing carbon monoxide according to any one of claims 1 to 5, wherein the decomposition reaction of the raw material is performed at 100 to 300°C.

7. An apparatus for producing carbon monoxide, which generates carbon monoxide by a decomposition reaction of a raw material of at least one of formic acid or a formic acid alkyl ester in the presence of a solid acid catalyst, the apparatus for producing carbon monoxide comprises a reactor that houses the solid acid catalyst and generates carbon monoxide by a decomposition reaction of a raw material in the presence of the solid acid catalyst, In the solid acid catalyst, the total pore volume of the pores having a pore diameter of 2 nm or less is 0.23 cm 3 / g or less.

8. The apparatus for producing carbon monoxide according to claim 7, wherein In the solid acid catalyst, the total pore volume of the fine pores is 0.20 cm 3 / g or less.

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