Method for producing alcohol

Abstract

The present invention relates to a method for producing alcohol from synthesis gas, wherein alcohol selectivity is improved and alcohol can be obtained more selectively. Said method for producing alcohol includes steps 1 and 2 below. Step 1: a catalyst production step for, in a non-aqueous solvent, causing a cobalt-containing compound (a) and a lanthanoid element-containing compound (b), which are soluble in the non-aqueous solvent, to react with a divalent or higher carboxylic acid compound (c), and obtaining a catalyst from the reaction product. Step 2: An alcohol production step for obtaining alcohol by reacting synthesis gas in the presence of the catalyst obtained in step 1.

Description

Alcohol production method

[0001] The present invention relates to a method for producing an alcohol, a method for producing a catalyst, and its use for producing an alcohol.

[0002] Syngas, a mixture of carbon monoxide and hydrogen, is one of the basic raw materials in C1 chemistry and is produced by using steam from coal, natural gas, heavy oil, petroleum exhaust gas, oil shale, biomass, etc. The composition of the syngas thus obtained is adjusted depending on its intended use, and it is used in technologies for producing organic compounds from syngas, such as the Fischer-Tropsch reaction (FT reaction). The inventors focused on a technology for producing alcohol from syngas as an application of this technology.

[0003] One such technique involves the reaction of CO and H in the presence of a cobalt-containing catalyst. ２ A method for producing alcohol by reacting a synthesis gas containing

[0004] Patent Document 1 discloses a catalyst for producing alcohol, which comprises an active component, an auxiliary, and a carrier, in which the active component is cobalt, the auxiliary element is one or more selected from rare earth elements, alkaline earth metals, Ti, Mn, Zr, Cu, Al, and B, and the carrier is a silicon-modified petroleum coke-based activator, and also discloses a method for producing alcohol from synthesis gas using this catalyst.

[0005] Chinese Patent Publication No. 111375417

[0006] In recent years, efforts to achieve carbon neutrality have been progressing in many countries, and efforts to develop alternative fuels to reduce carbon dioxide emissions from conventional fossil fuels are attracting attention. ２There is a method for producing alcohol using a synthesis gas containing the above-mentioned components as a raw material. As a method for producing alcohol using a synthesis gas as a raw material, alcohol can be produced by a catalytic reaction using the above-mentioned catalyst. However, in such a catalytic reaction, the proportion of alcohol produced in the reaction product (alcohol selectivity) is insufficient. Even in the invention described in Patent Document 1, the alcohol selectivity in alcohol production using the catalyst remained low.

[0007] The present invention is a method for producing a compound of CO and H ２ The present invention relates to a method for producing alcohol from a synthesis gas containing toluene, which can improve alcohol selectivity and more selectively obtain alcohol.

[0008] The present inventors have found that a catalyst obtained from the reaction product obtained by using a cobalt-containing compound and a lanthanoid-containing compound, both of which are soluble in a non-aqueous solvent, as raw material compounds and reacting them with a precipitant containing a divalent or higher carboxylic acid compound in a non-aqueous solvent can improve alcohol selectivity when producing alcohol from synthesis gas.

[0009] That is, the present invention relates to the following [1] to [3]. [1] A method for producing an alcohol, comprising the following steps 1 and 2: Step 1: A catalyst production step in which, in a non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are reacted with a divalent or higher carboxylic acid compound (c) to obtain a catalyst from the reaction product; and Step 2: An alcohol production step in which a synthesis gas is reacted in the presence of the catalyst obtained in step 1 to obtain an alcohol. [2] A catalyst production method in which, in a non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are reacted with a divalent or higher carboxylic acid compound (c) to obtain a catalyst from the reaction product. [3] A method for producing an alcohol by reacting a cobalt-containing compound (a) and a lanthanoid-containing compound (b), which are soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent, and using a catalyst obtained from the reaction product to react carbon monoxide and hydrogen in a synthesis gas.

[0010] According to the present invention, there are provided a method for producing alcohol from a synthesis gas, which can improve alcohol selectivity and enable more selective production of alcohol, a method for producing a catalyst used in the alcohol production method, and use of the catalyst for producing alcohol.

[0011] The alcohol production method of the present invention has the steps described below. [Alcohol Production Method] The alcohol production method of this embodiment has the following steps 1 and 2. Step 1: A catalyst production step in which a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are reacted with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent to obtain a catalyst from the reaction product. Step 2: An alcohol production step in which a synthesis gas is reacted in the presence of the catalyst obtained in step 1 to obtain an alcohol.

[0012] According to the present invention, there is provided a method for producing alcohol from a synthesis gas, which can improve the alcohol selectivity and enable more selective production of alcohol.

[0013] In the present invention, "producing alcohol from synthesis gas" means producing alcohol from CO (carbon monoxide) and H ２ In the present invention, "producing alcohol by reacting synthesis gas" refers to the reaction of CO and H in the synthesis gas. ２ and reacting them to produce alcohol.

[0014] In the present invention, "soluble in a non-aqueous solvent" means that each component dissolves in the non-aqueous solvent described below at the temperature during preparation of the raw material solution, and from the viewpoint of catalyst production efficiency, the solubility is preferably 10 g / 100 g (non-aqueous solvent, 25°C) or more, more preferably 20 g / 100 g (non-aqueous solvent, 25°C) or more.

[0015] The alcohol production method of this embodiment will be described in detail below. <Step 1> Catalyst Production Step Step 1 is a catalyst production step in which a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are reacted with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent to obtain a catalyst from the reaction product. More specifically, Step 1 is a catalyst production step in which the cobalt-containing compound (a) and the lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are coprecipitated in the non-aqueous solvent with a precipitant containing the divalent or higher carboxylic acid compound (c), and the catalyst is then obtained from the coprecipitated reaction product. Examples of methods for obtaining a catalyst in this catalyst production step include the catalyst production methods described below.

[0016] [Non-aqueous solvent] The non-aqueous solvent used herein is a solvent other than water that can dissolve the precipitant containing the cobalt-containing compound (a), the lanthanoid-containing compound (b), and the divalent or higher carboxylic acid compound (c). On the other hand, this non-aqueous solvent does not dissolve but precipitates a reaction product obtained by reacting the precipitant containing the divalent or higher carboxylic acid compound (c) with the cobalt-containing compound (a) and the lanthanoid-containing compound (b).

[0017] The nonaqueous solvent is preferably a solvent that can efficiently proceed with the reaction and obtain a reaction product having a uniform composition by coprecipitation. In terms of good solubility of the raw material compounds and insolubilization of the reaction product, the nonaqueous solvent has a relative dielectric constant at 20°C of preferably 3.0 or more, more preferably 10.0 or more, even more preferably 15.0 or more, and preferably 40.0 or less, more preferably 35.0 or less, even more preferably 30.0 or less, and also preferably 3.0 or more and 40.0 or less, more preferably 10.0 or more and 35.0 or less, even more preferably 15.0 or more and 30.0 or less.

[0018] Examples of the non-aqueous solvent include alcohols, ethers, and ketones, and more specifically, examples thereof include alcohols such as ethanol (dielectric constant: 24.6, 20°C), isopropanol (dielectric constant: 18.3, 20°C), 1-propanol (dielectric constant: 20.2, 20°C), and 1-butanol (dielectric constant: 17.3, 20°C), ethers such as diethyl ether (dielectric constant: 4.3, 20°C) and tetrahydrofuran (dielectric constant: 7.6, 20°C), and ketones such as acetone (dielectric constant: 21.5, 20°C). A mixed solvent containing a plurality of solvents may be used as long as it has the above-mentioned properties. From the above viewpoints, the non-aqueous solvent preferably contains one or more solvents selected from the group consisting of alcohols, ethers, and ketones, more preferably one or more solvents selected from the group consisting of ethanol, isopropanol, 1-propanol, 1-butanol, diethyl ether, tetrahydrofuran, and acetone, even more preferably one or more solvents selected from the group consisting of ethanol and isopropanol, and still more preferably ethanol.

[0019] The non-aqueous solvent may contain water to the extent that it does not affect the reaction. The water content in the non-aqueous solvent may be, for example, less than 1 mass %, less than 0.8 mass %, or less than 0.6 mass %.

[0020] [Cobalt-containing compound (a)] The cobalt-containing compound (a) is a compound containing cobalt as a catalytically active material, which dissolves in a non-aqueous solvent and can be coprecipitated with a lanthanoid-containing compound (b) described later by reaction with a precipitant containing a divalent or higher carboxylic acid compound (c) in the non-aqueous solvent. Examples of the cobalt-containing compound (a) include cobalt salts, and from the viewpoint of improving catalytic performance, the cobalt-containing compound (a) preferably contains at least one selected from the group consisting of cobalt sulfate, cobalt chloride, cobalt bromide, cobalt iodide, cobalt acetate, and cobalt nitrate, more preferably at least one selected from the group consisting of cobalt acetate and cobalt nitrate, and even more preferably cobalt nitrate.

[0021] [Lanthanoid-containing compound (b)] The lanthanoid-containing compound (b) is a compound that contains a lanthanoid element and dissolves in a non-aqueous solvent, and can be coprecipitated with the cobalt-containing compound (a) by reaction with a precipitating agent containing a divalent or higher carboxylic acid compound (c) in the non-aqueous solvent. The lanthanoid element contained in the lanthanoid-containing compound (b) is not particularly limited, and is at least one selected from the group consisting of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, and from the viewpoint of improving catalytic performance, is preferably at least one selected from the group consisting of lanthanum and cerium.

[0022] The lanthanoid element-containing compound (b) is, for example, a salt of a lanthanoid element, and preferably contains at least one selected from the group consisting of sulfates, acetates, nitrates, chlorides, bromides, and iodides. From the viewpoint of improving catalytic performance, the lanthanoid element-containing compound (b) preferably contains at least one selected from the group consisting of lanthanum acetate, lanthanum nitrate, lanthanum sulfate, lanthanum chloride, lanthanum bromide, lanthanum iodide, cerium acetate, cerium nitrate, cerium sulfate, cerium chloride, cerium bromide, and cerium iodide, more preferably at least one selected from the group consisting of lanthanum acetate, lanthanum nitrate, cerium acetate, and cerium nitrate, and even more preferably at least one selected from the group consisting of lanthanum nitrate and cerium nitrate.

[0023] [Precipitant containing a divalent or higher carboxylic acid compound (c)] This precipitant contains a divalent or higher carboxylic acid compound (c), i.e., a compound having two or more carboxy groups per molecule. This precipitant containing a divalent or higher carboxylic acid compound (c) (hereinafter sometimes referred to as the "precipitant") is soluble in a non-aqueous solvent, and in the non-aqueous solvent, the carboxylic acid compound reacts with a cobalt-containing compound (a) and a lanthanoid-containing compound (b), resulting in coprecipitating the resulting reaction product (a cobalt-lanthanoid composite compound). This precipitant may contain a divalent or higher carboxylic acid compound. From the viewpoint of improving catalytic performance, the divalent or higher carboxylic acid compound preferably contains a carboxylic acid compound having 2 to 6 carbon atoms, more preferably at least one selected from the group consisting of oxalic acid, malonic acid, succinic acid, malic acid, and citric acid, even more preferably at least one selected from the group consisting of oxalic acid, malic acid, and citric acid, even more preferably at least one selected from the group consisting of oxalic acid and citric acid, and even more preferably at least one selected from the group consisting of oxalic acid and citric acid, and even more preferably oxalic acid. When the precipitant contains a divalent or higher carboxylic acid compound, the reactivity with the cobalt-containing compound (a) and the lanthanoid-containing compound (b) is improved, allowing for efficient formation of a precipitate. It should be noted that the precipitant may contain a precipitant other than the divalent or higher carboxylic acid compound, as long as it does not inhibit the formation of the desired cobalt-lanthanoid complex compound. Examples of such precipitants include sodium carbonate, sodium bicarbonate, and ammonium carbonate.

[0024] [Catalyst Production Method] The method for obtaining a catalyst in step 1 (catalyst production step) is a method for obtaining a catalyst from a reactant (cobalt-lanthanoid composite compound) coprecipitated by a predetermined coprecipitation method using the raw material compounds (a cobalt-containing compound and a lanthanoid-containing compound soluble in a non-aqueous solvent) as described above. For example, the catalyst production method may include separating the coprecipitated reactant, drying it, and further treating the resulting dried product by a conventionally known treatment method for reduction and immobilization to obtain a catalyst. This catalyst production method is preferably a catalyst production method comprising the following steps 1-1 to 1-5. Step 1-1: A step of coprecipitating, in the non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a precipitating agent containing a divalent or higher carboxylic acid compound (c). Step 1-2: A step of separating the reactant coprecipitated in step 1-1 from the mixed solution after the reaction. Step 1-3: A step of drying the precipitate obtained by separation in step 1-2. Step 1-4: A step of reducing the dried product obtained by drying in step 1-3. Step 1-5: A step of immobilizing the reduced product obtained in step 1-4 to obtain a catalyst.

[0025] Specifically, a cobalt-lanthanoid composite catalyst can be obtained by sequentially performing steps 1-1 to 1-5 described below. <Step 1-1> First, a non-aqueous solvent, a cobalt-containing compound (a) soluble in the non-aqueous solvent, and a lanthanoid-containing compound (b) soluble in the non-aqueous solvent are prepared. Next, the prepared cobalt-containing compound (a) and lanthanoid-containing compound (b) are uniformly dissolved in the non-aqueous solvent to form a raw material solution. In addition, a precipitant containing a divalent or higher carboxylic acid compound (c) is prepared. The prepared precipitant may be used as is, or may be dissolved in the non-aqueous solvent and used as a precipitant solution.

[0026] Next, the raw material solution is mixed with a precipitant containing a divalent or higher carboxylic acid compound (c), and the cobalt-containing compound (a) and the lanthanoid-containing compound (b) are reacted with the precipitant (c), resulting in the cobalt-lanthanoid composite compound, which is the reaction product, being coprecipitated (deposited). When the precipitant is used as is, the raw material solution and the precipitant are preferably mixed by adding the precipitant to the raw material solution. When a precipitant solution is used, the precipitant solution may be added to the raw material solution, or the raw material solution may be added to the precipitant solution. However, from the viewpoint of improving catalyst performance, it is preferable to add the precipitant solution to the raw material solution. In other words, when a precipitant solution is used, Step 1 preferably includes the following Steps 1a, 1b, and 1c, and more preferably includes the following Steps 1a, 1b, and 1c'. Step 1a: a step of uniformly dissolving the cobalt-containing compound (a) and the lanthanoid element-containing compound (b) in the non-aqueous solvent to obtain a raw material solution; Step 1b: a step of dissolving the precipitant in the non-aqueous solvent to obtain a precipitant solution; Step 1c: a step of mixing the raw material solution obtained in Step 1a with the precipitant solution obtained in Step 1b to coprecipitate the cobalt-containing compound (a) and the lanthanoid element-containing compound (b); and Step 1c': a step of adding the precipitant solution obtained in Step 1b to the raw material solution obtained in Step 1a to coprecipitate the cobalt-containing compound (a) and the lanthanoid element-containing compound (b).

[0027] It is believed that the state of network formation in the cobalt-lanthanoid complex compound obtained varies depending on the combination of the non-aqueous solvent, cobalt-containing compound (a), lanthanoid-containing compound (b), and precipitant. Although the details are unknown, it is believed that the state of the network formed here affects the alcohol selectivity in Step 2, which will be described later.

[0028] <Step 1-2> Next, the reactant (cobalt-lanthanoid composite compound) coprecipitated (precipitated) in step 1-1 is separated from the post-reaction mixed solution. This separation can be carried out by a common separation procedure used in the field of catalyst production, and preferably involves one or more procedures selected from the group consisting of filtration, evaporation to dryness, and centrifugation. Examples of filtration include filter filtration and filtration with an aid. This separation procedure preferably involves one or more procedures selected from the group consisting of filtration and evaporation to dryness, more preferably one or more procedures selected from the group consisting of filter filtration and evaporation to dryness.

[0029] <Step 1-3> Next, the precipitate obtained by separation in Step 1-2 is dried by a drying treatment generally used in the field of catalyst production, from the viewpoint of removing the non-aqueous solvent. The drying treatment includes one or more selected from the group consisting of air drying, hot air drying, heat drying, and reduced-pressure drying, preferably one or more selected from the group consisting of heat drying and reduced-pressure drying, and more preferably heat drying using a heater.

[0030] <Step 1-4> The dried product obtained by drying in step 1-3 is further reduced to obtain a cobalt-lanthanoid composite catalyst. This reduction treatment can be performed by a conventional reduction treatment in the field of catalyst production. A hydrogen-containing gas may be used for the reduction treatment. The hydrogen-containing gas is preferably one or more hydrogen-containing gases selected from the group consisting of a mixed gas of carbon monoxide and hydrogen and a hydrogen-containing inert gas, more preferably a hydrogen-containing inert gas. Here, the reduction treatment reduces cobalt to metal. From the viewpoint of improving catalytic activity, the temperature of the reduction treatment (e.g., the temperature of the mixed gas of carbon monoxide and hydrogen or the hydrogen-containing inert gas) is preferably 150°C or higher, more preferably 200°C or higher, even more preferably 250°C or higher, and even more preferably 300°C or higher. From the same viewpoint, the temperature is preferably 800°C or lower, more preferably 700°C or lower, even more preferably 600°C or lower, and even more preferably 500°C or lower. From the same viewpoint, the reduction temperature is preferably 150°C or higher and 800°C or lower, more preferably 200°C or higher and 700°C or lower, even more preferably 250°C or higher and 600°C or lower, and even more preferably 300°C or higher and 500°C or lower. From the viewpoint of improving catalytic activity, the reduction time of the reduction treatment is preferably more than 0 hours, more preferably 2 hours or higher, even more preferably 4 hours or higher, still more preferably 6 hours or higher, and even more preferably 8 hours or higher, and from the same viewpoint, it is preferably 24 hours or lower, more preferably 18 hours or lower, even more preferably 15 hours or lower, and even more preferably 12 hours or lower. From the same viewpoint, the reduction time is preferably more than 0 hours and 24 hours or lower, more preferably 2 hours or higher and 18 hours or lower, even more preferably 4 hours or higher and 15 hours or lower, still more preferably 6 hours or higher and 12 hours or lower, and even more preferably 8 hours or higher and 12 hours or lower. When the reduction treatment is carried out using the hydrogen-containing gas, the hydrogen concentration in the hydrogen-containing gas during the reduction treatment is, from the viewpoint of improving catalytic activity, preferably 1 vol% or more, more preferably 2 vol% or more, even more preferably 3 vol% or more, and still more preferably 4 vol% or more, and from the same viewpoint, preferably 100 vol% or less, more preferably 60 vol% or less, even more preferably 20 vol% or less, and still more preferably 10 vol% or less.

[0031] <Step 1-5> Then, the reduced product obtained in step 1-4 is passivated to improve catalytic activity. The passivation can be performed by a conventional passivation method used in the field of catalyst production. An oxygen-containing gas may be used for the passivation, and an oxygen-containing inert gas is preferred as the oxygen-containing gas. Here, cobalt is stabilized by the passivation. The passivation temperature (e.g., the temperature of the oxygen-containing inert gas) is preferably 100°C or less, more preferably 70°C or less, even more preferably 50°C or less, and even more preferably 40°C or less, from the viewpoint of catalyst stabilization through oxide film formation. From the same viewpoint, the passivation temperature is preferably 0°C or more, more preferably 10°C or more, even more preferably 20°C or more, and even more preferably 25°C or more. From the same viewpoint, the temperature is preferably 0°C or more and 100°C or less, more preferably 10°C or more and 70°C or less, even more preferably 20°C or more and 50°C or less, and even more preferably 25°C or more. The passivation treatment time is preferably 30 minutes or more, more preferably 1 hour or more, even more preferably 2 hours or more, and even more preferably 3 hours or more, from the viewpoint of catalyst stabilization through oxide film formation. From the same viewpoint, it is preferably 10 hours or less, more preferably 8 hours or less, even more preferably 6 hours or less, and even more preferably 4 hours or less. From the same viewpoint, it is preferably 30 minutes to 10 hours, more preferably 1 hour to 8 hours, even more preferably 2 hours to 6 hours, and even more preferably 3 hours to 4 hours. From the viewpoint of catalyst stabilization through oxide film formation, the oxygen concentration in the oxygen-containing gas during the passivation treatment is preferably 0.1 vol% or more, more preferably 0.5 vol% or more, even more preferably 0.8 vol% or more, and even more preferably 1.0 vol% or more. From the same viewpoint, it is preferably 10 vol% or less, more preferably 6.0 vol% or less, even more preferably 2.0 vol% or less, and even more preferably 1.5 vol% or less.

[0032] From the viewpoint of improving catalytic performance, the amounts of the cobalt-containing compound (a) and the lanthanoid-containing compound (b) used in the nonaqueous solvent are such that the amount of the lanthanoid element in the lanthanoid-containing compound (b) per 1 mol of cobalt in the cobalt-containing compound (a) is preferably 0.05 mol or more and preferably 1.20 mol or less, more preferably 1.00 mol or less, and also preferably 0.05 mol or more and 1.20 mol or less, more preferably 0.05 mol or more and 1.00 mol or less. The amounts of cobalt and lanthanoid element used in this catalyst production method are maintained at the same amounts in the resulting cobalt-lanthanoid composite catalyst.

[0033] When the lanthanoid element of the lanthanoid element-containing compound (b) is lanthanum, from the viewpoint of improving catalytic performance, the amount of the cobalt-containing compound (a) and the lanthanoid element-containing compound (b) blended in the non-aqueous solvent is, in terms of the amount of the lanthanoid element of the lanthanoid element-containing compound (b) per 1 mol of cobalt in the cobalt-containing compound (a), preferably 0.05 mol or more, more preferably 0.08 mol or more, even more preferably 0.10 mol or more, and preferably 1.20 mol or less, more preferably 0.80 mol or less, even more preferably 0.45 mol or less, and also preferably 0.05 mol or more and 1.20 mol or less, more preferably 0.08 mol or more and 0.80 mol or less, even more preferably 0.10 mol or more and 0.45 mol or less.

[0034] When the lanthanoid element of the lanthanoid element-containing compound (b) is cerium, the amounts of the cobalt-containing compound (a) and the lanthanoid element-containing compound (b) blended in the non-aqueous solvent, from the viewpoint of improving catalytic performance, are such that the amount of the lanthanoid element of the lanthanoid element-containing compound (b) per 1 mol of cobalt in the cobalt-containing compound (a) is preferably 0.05 mol or more and preferably 1.20 mol or less, more preferably 0.98 mol or less, even more preferably 0.75 mol or less, still more preferably 0.50 mol or less, still more preferably 0.35 mol or less, and also preferably 0.05 mol or more and 1.20 mol or less, more preferably 0.05 mol or more and 0.98 mol or less, even more preferably 0.05 mol or more and 0.75 mol or less, still more preferably 0.05 mol or more and 0.50 mol or less, and still more preferably 0.05 mol or more and 0.35 mol or less.

[0035] The amount of the precipitant blended in the non-aqueous solvent is such that the molar ratio (precipitant / (cobalt content+lanthanoid content)) to the total content of the cobalt content in the cobalt-containing compound (a) and the lanthanoid content in the lanthanoid-containing compound (b) is preferably 0.90 or more, more preferably 0.95 or more, and is preferably 1.5 or less, more preferably 1.2 or less, and is preferably 0.90 or more and 1.5 or less, more preferably 0.95 or more and 1.2 or less.

[0036] Furthermore, the temperature of the nonaqueous solvent and / or mixture during co-precipitation in the nonaqueous solvent is preferably 5°C or higher, more preferably 15°C or higher, even more preferably 20°C or higher, and is preferably 50°C or lower, more preferably 40°C or lower, even more preferably 30°C or lower, from the viewpoint of stability of the reactant (precipitate) and prevention of solvent evaporation, and is also preferably 5°C or higher and 50°C or lower, more preferably 15°C or higher and 40°C or lower, even more preferably 20°C or higher and 30°C or lower.

[0037] <Step 2> Alcohol Production Step In this step 2, carbon monoxide (CO) and hydrogen (H ２In this step 2, alcohol is obtained from synthesis gas containing CO and H in the presence of a cobalt-lanthanide composite catalyst. ２ This method involves reacting a synthesis gas (feedstock gas) containing the cobalt-lanthanoid complex catalyst with a solvent to produce alcohol. For example, alcohol can be produced by placing a solvent and a cobalt-lanthanoid composite catalyst in a reaction vessel and passing the synthesis gas through the reaction vessel. Since the catalyst and the synthesis gas exist in different phases, it is desirable to promote mass transfer between the phases by, for example, bubbling the gas into the liquid. By using the cobalt-lanthanoid composite catalyst obtained by the above-described method, this embodiment can improve the alcohol selectivity in the reaction mixture compared to conventionally known methods.

[0038] The synthesis gas used in step 2 is CO and H ２ The synthesis gas can be obtained by a conventional method, for example, steam reforming of hydrocarbons such as natural gas and liquefied petroleum gas, or partial oxidation of fuels or biomass. ２ From the viewpoint of improving productivity, the composition of ２ Molar ratio (H ２ / CO) is preferably 1.0 or more, more preferably 1.3 or more, even more preferably 1.8 or more, and is preferably 2.5 or less, more preferably 2.4 or less, even more preferably 2.2 or less, and is preferably 1.0 or more and 2.5 or less, more preferably 1.3 or more and 2.4 or less, even more preferably 1.8 or more and 2.2 or less.

[0039] A gas phase is present in the reaction system when producing alcohol in step 2, and it is preferable to carry out the reaction under a synthesis gas atmosphere in order to maintain the activity of the catalyst. The reaction pressure (gauge pressure) of this gas phase is preferably 3.0 MPa or more, more preferably 4.0 MPa or more, even more preferably 5.0 MPa or more, and even more preferably 5.5 MPa or more from the viewpoint of improving catalyst performance, and is preferably 50 MPa or less, more preferably 30 MPa or less, even more preferably 10 MPa or less, and even more preferably 7.0 MPa or less from the viewpoint of reducing the burden on the equipment. Also, it is preferably 3.0 MPa or more and 50 MPa or less, more preferably 4.0 MPa or more and 40 MPa or less, even more preferably 5.0 MPa or more and 30 MPa or less, and even more preferably 5.5 MPa or more and 7.0 MPa or less.

[0040] The temperature of the solvent in step 2 (reaction temperature) is preferably 100°C or higher, more preferably 150°C or higher, even more preferably 200°C or higher, and still more preferably 230°C or higher, from the viewpoint of improving catalytic activity, and is preferably 300°C or lower, more preferably 270°C or lower, and even more preferably 250°C or lower, from the viewpoint of improving energy efficiency, and is also preferably 100°C or higher and 300°C or lower, more preferably 150°C or higher and 300°C or lower, even more preferably 200°C or higher and 270°C or lower, and still more preferably 230°C or higher and 250°C or lower.

[0041] The reactor in which the reaction of step 2 is carried out is preferably an reactor selected from the group consisting of a slurry bed reactor and a fixed bed reactor, more preferably a slurry bed reactor. In particular, from the viewpoints of catalyst durability (suppression of catalyst pore clogging) and stable production (high reaction heat removal efficiency), it is preferable to use a slurry bed reactor using a slurry bed (liquid-phase reaction). Note that the stable production refers to a state in which consistent quality and production volume can be maintained continuously under certain reaction conditions.

[0042] In the alcohol production method of this embodiment, as described above, CO and H ２In a method for producing alcohol from a synthesis gas containing CO, the alcohol selectivity can be improved, and alcohol can be obtained more selectively. The alcohol obtained in this case is, for example, a straight-chain alcohol having about 1 to 20 carbon atoms, although it is affected by the reaction conditions, etc. The alcohol obtained in this manner can be used as various alcohols, and can also be used as a raw material for various organic compounds. Among them, alcohols having 2 or more carbon atoms can be used as organic solvents, disinfectants, cleaning agents, fuels, etc. The catalyst produced by the catalyst production method of this embodiment is obtained in a step corresponding to step 1 of the alcohol production method, and is a catalyst obtained by reacting CO and H ２ The present invention has the effect of improving the alcohol selectivity in a method for producing alcohol from a synthesis gas containing the above-mentioned compound, and is therefore useful as a catalyst in the method for producing alcohol.

[0043] [Use for Producing Alcohol] The use for producing alcohol of the present embodiment involves reacting a cobalt-containing compound (a) and a lanthanoid-containing compound (b), which are soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent, and using a catalyst obtained from the reaction product to react carbon monoxide and hydrogen in a synthesis gas to produce alcohol.

[0044] In addition to the above-described embodiments, the present invention discloses the following: <1> A method for producing an alcohol, comprising the following steps 1 and 2: Step 1: a catalyst production step in which a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are coprecipitated in the non-aqueous solvent with a precipitant containing a divalent or higher carboxylic acid compound (c), and a catalyst is obtained from the coprecipitated reactant; and Step 2: an alcohol production step in which a synthesis gas is reacted in the presence of the catalyst obtained in Step 1 to obtain an alcohol. <2> The method for producing an alcohol according to <1>, wherein the non-aqueous solvent has a relative dielectric constant at 20°C of 3.0 or more and 40.0 or less, preferably 10.0 or more and 35.0 or less, and more preferably 15.0 or more and 30.0 or less. <3> The method for producing an alcohol according to <1> or <2>, wherein the non-aqueous solvent is at least one selected from the group consisting of alcohols, ethers, and ketones, preferably at least one selected from the group consisting of ethanol, isopropanol, 1-propanol, 1-butanol, diethyl ether, tetrahydrofuran, and acetone, and contains at least one selected from the group consisting of ethanol and isopropanol, more preferably at least one selected from the group consisting of ethanol and isopropanol, and even more preferably ethanol. <4> The method for producing an alcohol according to any one of <1> to <3>, wherein the cobalt-containing compound (a) is a cobalt salt, preferably at least one selected from the group consisting of cobalt sulfate, cobalt chloride, cobalt bromide, cobalt iodide, cobalt acetate, and cobalt nitrate, more preferably at least one selected from the group consisting of cobalt acetate and cobalt nitrate, and even more preferably cobalt nitrate. <5> The method for producing an alcohol according to any one of <1> to <4>, wherein the lanthanoid element of the lanthanoid element-containing compound (b) is at least one selected from the group consisting of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, preferably at least one selected from the group consisting of lanthanum and cerium, more preferably at least one selected from the group consisting of lanthanum and cerium.<6> The method for producing an alcohol according to any one of <1> to <5>, wherein the lanthanoid-containing compound (b) is a salt of a lanthanoid element, and is preferably at least one selected from the group consisting of sulfates, acetates, nitrates, chlorides, bromides, and iodides, more preferably at least one selected from the group consisting of lanthanum acetate, lanthanum nitrate, lanthanum sulfate, lanthanum chloride, lanthanum bromide, lanthanum iodide, cerium acetate, cerium nitrate, cerium sulfate, cerium chloride, cerium bromide, and cerium iodide, even more preferably at least one selected from the group consisting of lanthanum acetate, lanthanum nitrate, cerium acetate, and cerium nitrate, and still more preferably at least one selected from the group consisting of lanthanum nitrate and cerium nitrate. <7> The method for producing an alcohol according to any one of <1> to <6>, wherein in step 1, the amount of the lanthanoid element in the lanthanoid element-containing compound (b) relative to 1 mol of cobalt in the cobalt-containing compound (a) is preferably 0.05 mol or more and preferably 1.20 mol or less, more preferably 1.00 mol or less, and also preferably 0.05 mol or more and 1.20 mol or less, more preferably 0.05 mol or more and 1.00 mol or less. <8> The method for producing an alcohol according to any one of <1> to <7>, wherein the precipitating agent is a carboxylic acid compound having 2 to 6 carbon atoms, and is preferably at least one selected from the group consisting of oxalic acid, malonic acid, succinic acid, malic acid, and citric acid, more preferably at least one selected from the group consisting of oxalic acid, malic acid, and citric acid, even more preferably at least one selected from the group consisting of oxalic acid and citric acid, still more preferably at least one selected from the group consisting of oxalic acid and citric acid, and even more preferably oxalic acid. <9> The method for producing an alcohol according to any one of <1> to <8>, wherein the cobalt-containing compound (a) is one or more cobalt salts selected from the group consisting of cobalt acetate and cobalt nitrate; the lanthanoid element of the lanthanoid element-containing compound (b) is one or more selected from the group consisting of lanthanum and cerium; the precipitating agent is one or more selected from the group consisting of oxalic acid and citric acid; and the non-aqueous solvent is one or more selected from the group consisting of ethanol and isopropanol.<10> The method for producing an alcohol according to any one of <1> to <9>, wherein the cobalt-containing compound (a) is cobalt nitrate, the lanthanoid element of the lanthanoid element-containing compound (b) is lanthanum, the precipitating agent is oxalic acid, and the non-aqueous solvent is ethanol. <11> The method for producing an alcohol according to any one of <1> to <9>, wherein the cobalt-containing compound (a) is a cobalt salt selected from the group consisting of cobalt acetate and cobalt nitrate, the lanthanoid element-containing compound (b) is one or more selected from the group consisting of lanthanum nitrate and cerium nitrate, the precipitating agent is one or more selected from the group consisting of oxalic acid and citric acid, and the non-aqueous solvent is one or more selected from the group consisting of ethanol and isopropanol. <12> The method for producing an alcohol according to any one of <1> to <11>, wherein the cobalt-containing compound (a) is cobalt nitrate, the lanthanoid-containing compound (b) is lanthanum nitrate, the precipitating agent is oxalic acid, and the non-aqueous solvent is ethanol. <13> The molar ratio of hydrogen to carbon monoxide in the synthesis gas (H. ２<14> The method for producing an alcohol according to any one of <1> to <13>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <15> The method for producing an alcohol according to any one of <1> to <14>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <16> The method for producing an alcohol according to any one of <1> to <15>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <17> The method for producing an alcohol according to any one of <1> to <16>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <18> The method for producing an alcohol according to any one of <1> to <16>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <19> The method for producing an alcohol according to any one of <1> to <17>, wherein the reaction mixture is ethanol, ethanolamine, or ethanolamine. <20> <15> The method for producing an alcohol according to <14>, wherein the step 1c is the following step 1c': Step 1c': Adding the precipitant solution obtained in step 1b to the raw material solution obtained in step 1a to coprecipitate the cobalt-containing compound (a) and the lanthanoid-containing compound (b). <16> The method for producing an alcohol according to any one of <1> to <15>, wherein the step 1 comprises a step of separating the coprecipitated reaction product from the mixed solution after the reaction and drying the reactant. <17> The method for producing an alcohol according to any one of <1> to <16>, wherein in step 1, the method comprises a step of separating a coprecipitated reaction product from the mixed solution after the reaction and drying the product, and the drying is at least one method selected from the group consisting of air drying, hot air drying, heat drying, and reduced-pressure drying, preferably at least one method selected from the group consisting of heat drying and reduced-pressure drying, and more preferably heat drying using a heater. <18> The method for producing an alcohol according to any one of <1> to <17>, wherein in step 1, the method comprises a step of separating a coprecipitated reaction product from the mixed solution after the reaction and drying the product, and further subjecting the obtained dried product to a reduction treatment and a passivation treatment.<19> The method for producing an alcohol according to any one of <1> to <18>, wherein in step 1, the catalyst is obtained by reducing the coprecipitated reactant, and the reduction is carried out with one or more hydrogen-containing gases selected from the group consisting of a mixed gas of carbon monoxide and hydrogen and a hydrogen-containing inert gas. <20> The method for producing an alcohol according to any one of <1> to <19>, wherein in step 1, the catalyst is obtained by reducing the coprecipitated reactant, and the temperature of the reduction is preferably 150°C or higher, more preferably 200°C or higher, even more preferably 250°C or higher, still more preferably 300°C or higher, and preferably 800°C or lower, more preferably 700°C or lower, even more preferably 600°C or lower, still more preferably 500°C or lower, and from the same viewpoint, preferably 150°C or higher and 800°C or lower, more preferably 200°C or higher and 700°C or lower, even more preferably 250°C or higher and 600°C or lower, still more preferably 300°C or higher and 500°C or lower. <21> The method for producing an alcohol according to any one of <1> to <20>, wherein in step 1, the catalyst is obtained by subjecting the coprecipitated reactant to a reduction treatment, and the time for the reduction treatment is preferably longer than 0 hours, more preferably 2 hours or more, even more preferably 4 hours or more, still more preferably 6 hours or more, still more preferably 8 hours or more, and preferably 24 hours or less, more preferably 18 hours or less, even more preferably 15 hours or less, and still more preferably 12 hours or less; and from the same viewpoint, preferably longer than 0 hours and 24 hours or less, more preferably 2 hours or more and 18 hours or less, even more preferably 4 hours or more and 15 hours or less, still more preferably 6 hours or more and 12 hours or less, and still more preferably 8 hours or more and 12 hours or less.<22> The method for producing an alcohol according to any one of <1> to <21>, wherein in step 1, the catalyst is obtained by reducing the coprecipitated reactant, the reduction being preferably carried out with one or more hydrogen-containing gases selected from the group consisting of a mixed gas of carbon monoxide and hydrogen and a hydrogen-containing inert gas, and the hydrogen concentration in the hydrogen-containing gas during the reduction is preferably 1 vol% or more, more preferably 2 vol% or more, even more preferably 3 vol% or more, still more preferably 4 vol% or more, and preferably 100 vol% or less, more preferably 60 vol% or less, even more preferably 20 vol% or less, and still more preferably 10 vol% or less. <23> The method for producing an alcohol according to any one of <1> to <22>, wherein in step 1, the catalyst is obtained by reducing the coprecipitated reactant and then passivating it, and the passivation is carried out with an oxygen-containing gas, preferably an oxygen-containing inert gas. <24> The method for producing an alcohol according to any one of <1> to <23>, wherein in step 1, the catalyst is obtained by subjecting the coprecipitated reaction product to a reduction treatment and then to a passivation treatment, and the temperature of the passivation treatment is preferably 100°C or lower, more preferably 70°C or lower, even more preferably 50°C or lower, and still more preferably 40°C or lower, and is preferably 0°C or higher, more preferably 10°C or higher, even more preferably 20°C or higher, and still more preferably 25°C or higher, and is also preferably 0°C or higher and 100°C or lower, more preferably 10°C or higher and 70°C or lower, even more preferably 20°C or higher and 50°C or lower, and still more preferably 25°C or higher and 40°C or lower. <25> The method for producing an alcohol according to any one of <1> to <24>, wherein in step 1, the catalyst is obtained by subjecting the coprecipitated reactant to a reduction treatment and then to a passivation treatment, and the time for the passivation treatment is preferably 30 minutes or more, more preferably 1 hour or more, even more preferably 2 hours or more, still more preferably 3 hours or more, and preferably 10 hours or less, more preferably 8 hours or less, even more preferably 6 hours or less, still more preferably 4 hours or less, and also preferably 30 minutes to 10 hours, more preferably 1 hour to 8 hours, even more preferably 2 hours to 6 hours, still more preferably 3 hours to 4 hours.<26> The method for producing an alcohol according to any one of <1> to <25>, wherein in Step 1, the catalyst is obtained by subjecting the coprecipitated reactant to a reduction treatment and then a passivation treatment, the passivation treatment being carried out with an oxygen-containing gas, and the oxygen concentration in the oxygen-containing gas during the passivation treatment is preferably 0.1 vol% or more, more preferably 0.5 vol% or more, even more preferably 0.8 vol% or more, still more preferably 1.0 vol% or more, and preferably 10 vol% or less, more preferably 6.0 vol% or less, even more preferably 2.0 vol% or less, and still more preferably 1.5 vol% or less. <27> The method for producing an alcohol according to any one of <1> to <26>, wherein Step 1 is a catalyst production step of coprecipitating, in a non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a precipitant containing a divalent or higher carboxylic acid compound (c), and then obtaining the catalyst from the coprecipitated reactant. <28> The method for producing an alcohol according to any one of <1> to <27>, wherein the reaction in step 2 is carried out in an apparatus selected from the group consisting of a slurry bed reactor and a fixed bed reactor, preferably a slurry bed reactor. <29> The method for producing an alcohol according to any one of <1> to <28>, wherein in step 2, a gas phase is present in the reaction system when producing the alcohol, and the reaction pressure (gauge pressure) of this gas phase is preferably 3.0 MPa or more, more preferably 4.0 MPa or more, even more preferably 5.0 MPa or more, still more preferably 5.5 MPa or more, and preferably 50 MPa or less, more preferably 30 MPa or less, even more preferably 10 MPa or less, still more preferably 7.0 MPa or less, and preferably 3.0 MPa or more to 50 MPa or less, more preferably 4.0 MPa or more to 40 MPa or less, even more preferably 5.0 MPa or more to 30 MPa or less, still more preferably 5.5 MPa or more to 7.0 MPa or less.<30> The method for producing an alcohol according to any one of <1> to <29>, wherein the reaction temperature in Step 2 is preferably 100°C or higher, more preferably 150°C or higher, even more preferably 200°C or higher, still more preferably 230°C or higher, and preferably 300°C or lower, more preferably 270°C or lower, even more preferably 250°C or lower, and also preferably 100°C or higher and 300°C or lower, more preferably 150°C or higher and 300°C or lower, even more preferably 200°C or higher and 270°C or lower, and still more preferably 230°C or higher and 250°C or lower. <31> The method for producing an alcohol according to any one of <1> to <30>, wherein in Step 2, a gas phase is present in the reaction system when producing the alcohol, the reaction pressure (gauge pressure) of the gas phase is 3.0 MPa or higher and 50 MPa or lower, and the reaction temperature is 100°C or higher and 300°C or lower. <32> The method for producing an alcohol according to any one of <1> to <31>, wherein in step 2, a gas phase is present in the reaction system when the alcohol is produced, the reaction pressure (gauge pressure) of the gas phase is 3.0 MPa or more and 50 MPa or less, and the reaction temperature is 150°C or more and 300°C or less. <33> The method for producing an alcohol according to any one of <1> to <32>, wherein in step 2, a gas phase is present in the reaction system when the alcohol is produced, the synthesis gas is reacted under a synthesis gas atmosphere, the reaction pressure (gauge pressure) is 4.0 MPa or more and 40 MPa or less, and the reaction temperature is 200°C or more and 270°C or less. <34> The method for producing an alcohol according to any one of <1> to <33>, wherein in step 2, a gas phase is present in the reaction system when the alcohol is produced, the synthesis gas is reacted under a synthesis gas atmosphere, the reaction pressure (gauge pressure) of the gas phase is 5.0 MPa or more and 30 MPa or less, and the reaction temperature is 230°C or more and 250°C or less. <35> The method for producing an alcohol according to any one of <1> to <34>, wherein in the step 2, a gas phase is present in the reaction system when producing the alcohol, the synthesis gas is reacted under a synthesis gas atmosphere, the reaction pressure (gauge pressure) of the gas phase is 5.5 MPa or more and 7.0 MPa or less, and the reaction temperature is 230°C or more and 250°C or less.<36> A method for producing a catalyst, comprising reacting a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent, and obtaining a catalyst from the reaction product. <37> A method for producing a catalyst, comprising the following step 1: step 1: coprecipitating the cobalt-containing compound (a) and the lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, in a non-aqueous solvent with a precipitant containing the divalent or higher carboxylic acid compound (c), and then obtaining a catalyst from the coprecipitated reaction product. <38> The method for producing a catalyst according to <37>, further comprising a step of separating the coprecipitated reaction product from the mixed solution after the reaction in step 1. <39> The method for producing a catalyst according to <38>, further comprising a step of drying the separated precipitate in step 1. <40> The method for producing a catalyst according to <39>, further comprising a step of reducing the dried product obtained by drying in step 1. <41> A method for producing a catalyst according to <40>, further comprising a step of immobilizing a reduction product obtained by the reduction. <42> A method for producing a catalyst, comprising the following steps 1-1 to 1-5: Step 1-1: coprecipitating, in a non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a precipitant containing a divalent or higher carboxylic acid compound (c); Step 1-2: separating the reactant coprecipitated in step 1-1 from the mixed solution after the reaction; Step 1-3: drying the precipitate obtained by separation in step 1-2; Step 1-4: reducing the dried product obtained by drying in step 1-3; and Step 1-5: immobilizing the reduction product reduced in step 1-4 to obtain a catalyst. <43> A method for producing an alcohol, comprising reacting a synthesis gas in the presence of a catalyst obtained by the method for producing a catalyst according to any one of <36> to <42>. <44> A method for producing an alcohol by reacting, in a non-aqueous solvent, a cobalt-containing compound (a) and a lanthanoid-containing compound (b), which are soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c), and using a catalyst obtained from the reaction product to react carbon monoxide and hydrogen in a synthesis gas.

[0045] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples. Measurements and evaluations in the examples were carried out by the methods described below. Unless otherwise specified, the samples were prepared at room temperature (25°C) and atmospheric pressure.

[0046] Example 1: Co-La Catalyst a) A 0.5 L vessel was charged with a stirrer tip (size 4.0 cm), and 6.74 g of cobalt(II) nitrate hexahydrate (Kanto Chemical Co., Inc.) (cobalt 23.2 mmol), 0.47 g of lanthanum(II) nitrate hexahydrate (Kanto Chemical Co., Inc.) (lanthanum 1.09 mmol), and 120 mL of ethanol were added and stirred at 600 rpm for 30 minutes to prepare Mixed Solution 1 (raw material solution: La / Co molar ratio 0.05). A 0.5 L vessel was charged with a stirrer tip (size 4.0 cm), and 2.18 g of oxalic acid (24.2 mmol) and 230 mL of ethanol were added and stirred at 600 rpm for 30 minutes to prepare a precipitant solution. After stirring, Mixed Solution 1 (120 mL) was added dropwise to the precipitant solution over 30 minutes. After the dropwise addition, the mixture was stirred at 600 rpm for 30 minutes. After stirring, the precipitate was filtered using a membrane filter (manufactured by ADVANTEC) with a pore size of 0.2 μm. The filtered material was dried at 120 ° C for 16 hours under an air atmosphere. The dried catalyst was placed in a reduction furnace (muffle furnace) for 30 minutes and cooled to room temperature (25 ° C). The air in the muffle furnace was replaced with nitrogen, and the muffle furnace was heated from room temperature (25 ° C) to 400 ° C over 3 hours under atmospheric pressure with nitrogen containing 4% hydrogen at 40 mL per minute. The mixture was then held at 400 ° C for 10 hours and reduced. After the reduction was completed, the nitrogen flow rate was changed to 40 mL per minute and the mixture was cooled to room temperature (25 ° C). After that, nitrogen containing 1% oxygen by volume was passed through the muffle furnace at 15 mL per minute for 240 minutes, and surface passivation treatment was performed to obtain Co-La catalyst a.

[0047] Next, a semi-batch autoclave (C-401, manufactured by Toyo Koatsu Co., Ltd.) with an internal volume of 100 mL was used as the reactor for producing alcohol from synthesis gas. 40 mL of n-hexadecane (manufactured by Kanto Chemical Co., Ltd.) and 0.5 g of a catalyst with an average particle size of 1 μm were placed in the reactor, and the inside of the piping was replaced with nitrogen. Then, synthesis gas (H ２A mixture of 1000kJ / CO (molar ratio) = 2.0, hydrogen content = 65 vol%, carbon monoxide content = 32 vol%, and argon content = 3 vol%) was supplied and aerated at 10 L / min, and the gauge pressure was increased to 6.0 MPa. After the pressure was increased, the temperature was increased from room temperature (25°C) to 240°C over 1 hour and 30 minutes. The reaction started when the temperature reached 240°C. The contents in the reactor were stirred at 1200 rpm, and the reaction was carried out for 3 hours, yielding a reaction product containing alcohol.

[0048] (Examples 2 to 3a: Co-La catalysts b to c) Co-La catalyst b (Example 2) and Co-La catalyst c (Example 3a) were obtained by the same procedure as in Example 1, except that the compounds and amounts used were as shown in Table 1. Furthermore, the obtained Co-La catalysts b to c were subjected to the same procedure as in Example 1, and a reaction product containing alcohol was obtained from synthesis gas. (Example 3b) Co-La catalyst c' was obtained by the same procedure as in Example 3a, except that in Example 3a, a precipitant solution was added dropwise to the raw material solution. Furthermore, the obtained Co-La catalyst c' was subjected to the same procedure as in Example 1, and a reaction product containing alcohol was obtained from synthesis gas.

[0049] (Example 4: Co-La Catalyst d) A stirrer tip (size 4.0 cm) was placed in a 1.0 L vessel, and 350 mL of cobalt(II) nitrate hexahydrate (Kanto Chemical), lanthanum(II) nitrate hexahydrate (Kanto Chemical), and ethanol were added. The mixture was stirred at 600 rpm for 30 minutes to prepare a mixed solution (raw material solution). Citric acid (Kanto Chemical) was added to the mixed solution in the amount shown in Table 1, and the mixture was stirred at 600 rpm for 30 minutes. The stirrer tip was then removed from the vessel, and the solvent was removed using an evaporator (BUCHI Catalog No. U00210), and the precipitate was recovered. The precipitate was dried in an air atmosphere at 120°C for 16 hours. The dried catalyst was placed in a reduction furnace (muffle furnace) for 30 minutes and then cooled to room temperature (25°C). The air in the muffle furnace was replaced with nitrogen, and nitrogen containing 4% by volume of hydrogen was passed through the muffle furnace at atmospheric pressure at 40 mL per minute. The temperature was raised from room temperature (25 ° C) to 400 ° C over 3 hours, and the mixture was held at 400 ° C for 10 hours, followed by reduction. After completion of reduction, the nitrogen was switched to 40 mL per minute, and the mixture was cooled to room temperature (25 ° C). Then, nitrogen containing 1% by volume of oxygen was passed through the muffle furnace at 15 mL per minute for 240 minutes, and surface passivation treatment was performed to obtain Co-La catalyst d (Example 4). Furthermore, the obtained Co-La catalyst d was operated in the same manner as in Example 1, and a reaction product containing alcohol was obtained from the synthesis gas.

[0050] (Examples 5 and 6: Co-La catalysts e to f) Co-La catalyst e (Example 5) and Co-La catalyst f (Example 6) were obtained by the same operation as in Example 1, except that the compounds and amounts used were as shown in Table 1. Furthermore, the obtained Co-La catalysts e to f were subjected to the same operation as in Example 1 to obtain a reaction product containing alcohol from the synthesis gas.

[0051] (Examples 7 to 10: Co-Ce catalysts g to j) Co-Ce catalyst g (Example 7), Co-Ce catalyst h (Example 8), Co-Ce catalyst i (Example 9), and Co-Ce catalyst j (Example 10) were obtained by the same procedure as in Example 1, except that the compounds and amounts used were as shown in Table 1. In these examples, cerium nitrate was used instead of lanthanum nitrate as the raw material. Furthermore, the obtained Co-Ce catalysts g to j were subjected to the same procedure as in Example 1, and a reaction product containing alcohol was obtained from the synthesis gas.

[0052] (Comparative Example 1: Production of Co catalyst) A Co catalyst was obtained by the same operation as in Example 1, except that the compounds and amounts used were as shown in Table 1. Furthermore, the obtained Co catalyst was subjected to the same operation as in Example 1, and a reaction product containing alcohol was obtained from synthesis gas. (Comparative Example 2: Co-La catalyst C1) A Co-La catalyst C1 was obtained by the same operation as in Example 3b, except that the compounds and amounts used were as shown in Table 1. In this example, water (relative dielectric constant: 80.0) was used as the solvent during catalyst formation. Furthermore, the obtained Co-La catalyst C1 was subjected to the same operation as in Example 1, and a reaction product containing alcohol was obtained from synthesis gas.

[0053] The catalyst, synthesis gas, and reaction products obtained as described above were analyzed for composition and components, and the CO conversion and selectivity for each compound were calculated. The results are summarized in Table 1.

[0054] [Method for Analyzing Gas Components During the Reaction] The gas components during the reaction were introduced every hour through the piping at the outlet of the reaction apparatus into a gas chromatograph (also referred to as GC) equipped with a thermal conductivity detector (also referred to as TCD) or a flame ionization detector (also referred to as FID), and GC analysis was performed using argon as an internal standard substance.

[0055] The volume concentration of carbon monoxide in the gaseous components was calculated by the internal standard method using argon as the internal standard from the GC peak area percentages attributable to carbon monoxide and argon. A calibration curve was prepared by measuring a gas mixture of standard gases consisting of carbon monoxide, methane, and carbon dioxide, and argon, and plotting the peak area ratios of carbon monoxide and argon against the volume concentration ratio of carbon monoxide and argon at each mixture ratio.

[0056] The volume concentration of methane in the gas components was calculated from the GC peak area percentages of methane and argon by the internal standard method using argon as the internal standard. A calibration curve was created by measuring a standard gas consisting of carbon monoxide, methane, and carbon dioxide, and a gas mixture containing argon, and plotting the peak area ratios of carbon monoxide and argon against the volume concentration ratio of methane and argon at each mixture ratio.

[0057] The volume concentration of olefins in the gaseous components was calculated by the following formula: Volume concentration % of olefins = Volume concentration % of methane × (GC peak area derived from all detected olefins of different carbon numbers / GC peak area derived from detected methane).

[0058] The volume concentration of paraffin in the gaseous components was calculated by the following formula: Volume concentration of paraffin % = Volume concentration of methane % × (GC peak area derived from paraffins of all detected carbon numbers / GC peak area derived from detected methane).

[0059] <GC measurement conditions> - For CO and methane Sample amount: 1 mL Gas chromatography: GC-320 (GL Sciences) Detector: TCD (built into gas chromatograph) Column: Active Carbon (GL Sciences, 60-80 mesh, column length 3 m, inner diameter 2 mm) Temperature condition: 80°C constant Carrier gas: H ２, inlet pressure 200 kPa Sample introduction part temperature: 110°C, detector temperature: 80°C - For olefins and paraffins Sample introduction amount: 0.8 mL Gas chromatography: GC-14B (Shimadzu Corporation) Detector: FID (built into gas chromatograph) Column: Porapak Q (GL Sciences, packing mesh size 80 / 100, column length 3 m, inner diameter 2 mm) Temperature conditions: 70°C → 230°C (heating rate 2°C / min) Carrier gas: N ２ , inlet pressure 200 kPa, sample introduction part temperature: 200°C, detector temperature: 230°C

[0060] [Analysis of Liquid Components of Reaction Product at Reaction Completion] After the reaction was completed and cooled to room temperature, the reactor and ice trap were removed. The products in the ice trap were mixed in the reactor, and deionized water was added to the mixture to separate the organic and aqueous layers. As internal standards, 0.1 g of 1-octanol (Kanto Chemical Co., Inc.) and 0.1 g of dodecane (Kanto Chemical Co., Inc.) were added to the organic layer, and 0.05 g of tert-butanol (Kanto Chemical Co., Inc.) was added to the aqueous layer. After thorough stirring, the resulting solution was subjected to GC analysis. 0.2 μL of each sample was directly introduced into the GC for GC analysis. The alcohol concentration in the organic layer was calculated using a conversion formula based on the area percentage of the detected GC peaks derived from each alcohol and the area percentage of the GC peak derived from dodecane. The conversion formula was determined from the peak areas of each alcohol of known concentration and 1-octanol of known concentration. The concentrations of olefins and paraffins in the organic layer were calculated using a conversion formula from the area % of the detected GC peaks derived from each olefin and paraffin and the area % of the GC peak derived from dodecane. The conversion formula was determined from the peak areas of each olefin, paraffin, and dodecane of known concentrations. The alcohol concentration in the aqueous layer was calculated using a conversion formula from the area % of the detected GC peak derived from each alcohol and the area % of the GC peak derived from tert-butanol. The conversion formula was determined from the peak areas of each alcohol concentration of known concentration and tert-butanol of known concentration. GC measurement conditions Sample introduction amount: 0.2 μL Gas chromatography: GC-2014 (Shimadzu Corporation)

[0061] [Methods for calculating CO conversion, alcohol selectivity, and alcohol selectivity having two or more carbon atoms] The CO conversion, alcohol selectivity, and alcohol selectivity having two or more carbon atoms (C ２＋ The conversion rate, alcohol selectivity, and alcohol selectivity were calculated according to the following formula. In the formula below, C-mol% (carbon mole %) is the ratio of the number of moles of carbon atoms in each product to the number of moles of carbon atoms in all products, and is expressed by the following formula: C-mol% (carbon mole %) = (number of moles of carbon atoms in each product / number of moles of carbon atoms in all products) × 100. The total amount of HC produced represents the total amount of hydrocarbons produced, and is calculated by the following formula: Total amount of HC produced (C-mol%) = total amount of olefins produced (C-mol%) + total amount of paraffins produced (C-mol%). The higher the CO conversion, alcohol selectivity, and selectivity to alcohols having two or more carbon atoms, the better the catalyst performance in light of the object of the present invention.

[0062] Calculation formula for reactants CO conversion rate (%) = (1 - (CO concentration (mol%) in gas components at reactor outlet / CO concentration (mol%) in gas supplied to reactor)) × 100 Alcohol selectivity (%; C-mol ratio) = (total amount of ROH produced (C-mol%) / (total amount of ROH produced (C-mol%) + total amount of HC produced (C-mol%))) × 100 C ２＋ Alcohol selectivity (%; C-molar ratio) = (C ２＋ Total amount of ROH produced (C-mol%) / (Total amount of ROH produced (C-mol%)+Total amount of HC produced (C-mol%))×100 Here, the total amount of ROH produced is calculated by dividing the total amount of alcohol produced by the total amount of C ２＋ The total amount of ROH produced means the total amount of alcohols produced having two or more carbon atoms. ２＋ The alcohol selectivity means the selectivity of alcohols having two or more carbon atoms, and differs from the alcohol selectivity in that it does not include methanol.

[0063]

[0064] From the above, it was found that in the alcohol production method of the present embodiment, by setting the production conditions of the obtained catalyst to predetermined conditions, the alcohol selectivity can be improved when alcohol is produced from synthesis gas using the catalyst.

Claims

1. A method for producing an alcohol, comprising the following steps 1 and 2: step 1: a catalyst production step in which a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, are reacted with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent to obtain a catalyst from the reaction product; and step 2: an alcohol production step in which a synthesis gas is reacted in the presence of the catalyst obtained in step 1 to obtain an alcohol.

2. The method for producing an alcohol according to claim 1, wherein the non-aqueous solvent has a relative dielectric constant at 20°C of 3.0 or more and 40.0 or less.

3. The method for producing an alcohol according to claim 2, wherein the non-aqueous solvent contains at least one selected from the group consisting of ethanol and isopropanol.

4. The method for producing an alcohol according to any one of claims 1 to 3, wherein the lanthanoid element in the lanthanoid-containing compound (b) is at least one selected from the group consisting of lanthanum and cerium.

5. The method for producing an alcohol according to any one of claims 1 to 4, wherein in step 1, the amount of the lanthanoid element in the lanthanoid element-containing compound (b) relative to 1 mol of cobalt in the cobalt-containing compound (a) is 0.05 mol or more and 1.20 mol or less.

6. The method for producing alcohol according to any one of claims 1 to 5, wherein (c) contains one or more acids selected from the group consisting of oxalic acid and citric acid.

7. The method for producing an alcohol according to any one of claims 1 to 6, wherein step 1 is a catalyst production step in which a cobalt-containing compound (a) and a lanthanoid-containing compound (b), which are soluble in the non-aqueous solvent, are coprecipitated in the non-aqueous solvent with a precipitating agent containing a divalent or higher carboxylic acid compound (c), and the catalyst is obtained from the coprecipitated reaction product.

8. The method for producing an alcohol according to any one of claims 1 to 7, wherein step 1 comprises the following steps 1a, 1b, and 1c: step 1a: uniformly dissolving the cobalt-containing compound (a) and the lanthanoid-containing compound (b) in the non-aqueous solvent to obtain a raw material solution; step 1b: dissolving the precipitant in the non-aqueous solvent to obtain a precipitant solution; and step 1c: mixing the raw material solution obtained in step 1a with the precipitant solution obtained in step 1b to co-precipitate the cobalt-containing compound (a) and the lanthanoid-containing compound (b).

9. The method for producing an alcohol according to claim 8, wherein step 1c is the following step 1c': Step 1c': A step of adding the precipitant solution obtained in step 1b to the raw material solution obtained in step 1a to coprecipitate the cobalt-containing compound (a) and the lanthanoid-containing compound (b).

10. The method for producing alcohol according to any one of claims 1 to 9, wherein step 2 is carried out in a slurry bed reactor.

11. A method for producing a catalyst, comprising reacting a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent, and obtaining a catalyst from the reaction product.

12. A method for producing alcohol by reacting a cobalt-containing compound (a) and a lanthanoid-containing compound (b), both soluble in the non-aqueous solvent, with a divalent or higher carboxylic acid compound (c) in a non-aqueous solvent, and using the catalyst obtained from the reaction product to react carbon monoxide and hydrogen in a synthesis gas.

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