Alkane manufacturing methods

Abstract

The present invention provides a method for producing alkanes that proceeds at a lower reaction temperature than conventional methods, suppresses the formation of by-products such as ethers, allows the use of ethers with chain lengths exceeding C2 as raw materials, and exhibits excellent conversion rate and selectivity. [Solution] A method for producing alkanes from ethers having 16 to 48 carbon atoms, comprising the step of reacting ethers having 16 to 48 carbon atoms with hydrogen in the presence of a zeolite catalyst and a metal of groups 8 to 10 of the periodic table, at a reaction temperature of 150°C or higher, a reaction time of 3 hours or higher, and a hydrogen pressure of 0 MPa or higher in gauge pressure, wherein the zeolite catalyst is one selected from H-beta type, H-ZSM-5 type, and HY type, and the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40.

Description

Technical Field

[0001] The present invention relates to a method for producing alkanes.

Background Art

[0002] Conventionally, methods for producing alkanes using alcohols that are abundant in nature as raw materials have been studied. Alkanes are chemically and thermally stable chemical substances and are used in a wide range of fields such as solvents for chemical reactions, paints, and toiletries.

[0003] Most of the alkanes currently in use are derived from petroleum and have the advantage of being inexpensive and obtainable in large quantities.

[0004] However, the use of petroleum-derived alkanes has contributed to the increase in the concentration of carbon dioxide on Earth. Therefore, there is a demand for producing alkanes from raw materials derived from biomass centered on plants.

[0005] Various methods have been studied for producing alkanes by reacting natural alcohols as raw materials in the presence of hydrogen and a catalyst. However, in conventional methods using natural alcohols as raw materials, it was necessary to remove the ether formed as a by-product.

[0006] For example, Non-Patent Document 1 discloses a method for decomposing dimethyl ether to produce methane, carbon dioxide, carbon monoxide, and hydrogen.

Prior Art Documents

Patent Documents

[0007]

Non-Patent Document 1

Summary of the Invention

[0008] The method described in Non-Patent Document 1 had a high reaction temperature of around 300°C, which presented problems with energy costs.

[0009] Furthermore, the method described in Patent Document 1 is limited to dimethyl ether as the substrate, and the decomposition of ethers having a chain length greater than C2 has not been achieved.

[0010] Therefore, the present invention provides a method for producing alkanes that proceeds at a lower reaction temperature compared to the method described in Non-Patent Document 1, suppresses the formation of by-products such as ethers, allows the use of ethers having a chain length greater than C2 as a starting material, and exhibits excellent conversion rate and selectivity. [Means for solving the problem]

[0011] As a result of diligent research, the inventors of the present invention have discovered that by reacting ether with hydrogen using a specific zeolite catalyst and metal, it is possible to produce alkanes from ether at a lower reaction temperature than conventional methods, and furthermore, the conversion rate and selectivity are also excellent, thus completing the present invention.

[0012] In other words, the present invention relates to a method for producing alkanes from ethers having 16 to 48 carbon atoms, comprising the step of reacting ethers having 16 to 48 carbon atoms with hydrogen in the presence of a zeolite catalyst and a metal of groups 8 to 10 of the periodic table, at a reaction temperature of 150°C or higher, a reaction time of 3 hours or higher, and a hydrogen pressure of 0 MPa or higher in gauge pressure, wherein the zeolite catalyst is one selected from H-beta type, H-ZSM-5 type, and HY type, and the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40.

[0013] In the method for producing alkanes of the present invention, the reaction temperature is preferably 180°C to 230°C. Furthermore, in the method for producing alkanes according to the present invention, it is preferable that the reaction time is 8 hours or less. Furthermore, in the method for producing alkanes according to the present invention, it is preferable that the hydrogen pressure is 3.0 MPa or less in gauge pressure. Furthermore, it is preferable that the metals in groups 8 to 10 of the periodic table are at least one selected from the group consisting of palladium, ruthenium, platinum, rhodium, and nickel. Furthermore, the zeolite catalyst is preferably of the H-beta or HY type and is used in an amount of 1% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms, and the metal of groups 8 to 10 of the periodic table is preferably palladium or platinum and is used in an amount of 0.01% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms. [Effects of the Invention]

[0014] The present invention provides a method for producing alkanes that allows the reaction to proceed at a lower reaction temperature, suppresses the formation of by-products such as ethers, can use ethers having a chain length greater than C2 as a starting material, and produces alkanes with excellent conversion rate and selectivity. [Modes for carrying out the invention]

[0015] The present invention relates to a method for producing alkanes from ethers having 16 to 48 carbon atoms, comprising the step of reacting ethers having 16 to 48 carbon atoms with hydrogen in the presence of a zeolite catalyst and a metal of groups 8 to 10 of the periodic table, at a reaction temperature of 150°C or higher, a reaction time of 3 hours or higher, and a hydrogen pressure of 0 MPa or higher in gauge pressure, wherein the zeolite catalyst is one selected from H-beta type, H-ZSM-5 type, and HY type, and the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40. The following describes in detail each component of the method for producing alkanes according to the present invention.

[0016] The method for producing an alkane according to the present invention comprises a step of reacting an ether having 16 to 48 carbon atoms with hydrogen under the conditions that the reaction temperature is 150 °C or higher, the reaction time is 3 hours or longer, and the hydrogen pressure is 0 MPa or higher in gauge pressure, in the presence of a zeolite catalyst and a metal of Groups 8 to 10 of the periodic table.

[0017] (Reaction temperature) In the step of reacting the ether having 16 to 48 carbon atoms with hydrogen, the reaction temperature is 150 °C or higher. When the reaction temperature is within the above range, the reaction for obtaining an alkane from the ether having 16 to 48 carbon atoms proceeds. The reaction temperature is preferably 180 °C to 230 °C.

[0018] (Hydrogen pressure) In the step of reacting the ether having 16 to 48 carbon atoms with hydrogen, the hydrogen pressure is 0 MPa or higher in gauge pressure. The reaction for obtaining an alkane from the ether having 16 to 48 carbon atoms sufficiently proceeds even when the hydrogen pressure is at normal pressure. The hydrogen pressure is preferably 3.0 MPa or lower in gauge pressure, more preferably 1.0 MPa or lower, and still more preferably 0.5 MPa or lower. Note that the gauge pressure means a pressure that does not include atmospheric pressure (atmospheric pressure is taken as 0 MPa).

[0019] (Reaction time) In the step of reacting the ether having 16 to 48 carbon atoms with hydrogen, the reaction time is 3 hours or longer. When the reaction time is within the above range, the reaction for obtaining an alkane from the ether having 16 to 48 carbon atoms sufficiently proceeds. The reaction time is preferably 8 hours or shorter, and more preferably 3 to 4 hours from the viewpoint of selectivity. Note that the reaction time means the time from reaching the above-described reaction temperature until the reaction is terminated.

[0020] (Zeolite catalyst) In the step of reacting the ether having 16 to 48 carbon atoms with hydrogen, a zeolite catalyst is used.

[0021] The above zeolite catalyst is one of the following types: H-beta type, H-ZSM-5 type, and HY type, and the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40. Note that H-beta type means that the crystal structure is beta type (BEA type) and the cation constituting the zeolite is hydrogen; H-ZSM-5 type means that the crystal structure is ZSM-5 type (MFI type) and the cation constituting the zeolite is hydrogen; and HY type means that the crystal structure is Y type and the cation constituting the zeolite is hydrogen.

[0022] In the above zeolite catalyst, the reaction to obtain alkanes from ethers with 16 to 48 carbon atoms proceeds when the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40.

[0023] When the above zeolite catalyst is of the H-beta type, the molar ratio (SiO2 / Al2O3) is most preferably 28 to 40. Examples of commercially available zeolite catalysts of this type include the HSZ-900 series 931HOA type and 940HOA type (manufactured by Tosoh Corporation).

[0024] Furthermore, if the zeolite catalyst is of the H-ZSM-5 type, the molar ratio (SiO2 / Al2O3) is most preferably 5 to 24. Examples of commercially available zeolite catalysts of this type include the HSZ-800 series 822HOA type (manufactured by Tosoh Corporation).

[0025] Furthermore, if the zeolite catalyst is of the HY type, the molar ratio (SiO2 / Al2O3) is most preferably 5 to 20. Examples of commercially available zeolite catalysts of this type include the HSZ-300 series 360HUA type (manufactured by Tosoh Corporation).

[0026] In the step of reacting the above-mentioned ether having 16 to 48 carbon atoms with hydrogen, from the viewpoint of suitably carrying out the reaction to obtain an alkane from the above-mentioned ether having 16 to 48 carbon atoms, it is preferable that the above-mentioned zeolite catalyst is of the H-beta type or HY type and is used in an amount of 1% by mass or more relative to the mass of the above-mentioned ether having 16 to 48 carbon atoms, and that the metal of Groups 8 to 10 of the periodic table, described later, is palladium or platinum and is used in an amount of 0.01% by mass or more relative to the mass of the above-mentioned ether having 16 to 48 carbon atoms.

[0027] (Metals in Groups 8-10 of the Periodic Table) In the process of reacting ethers with 16 to 48 carbon atoms with hydrogen, metals from groups 8 to 10 of the periodic table are used.

[0028] The metals in groups 8 to 10 of the periodic table mentioned above are preferably at least one selected from the group consisting of palladium, ruthenium, platinum, rhodium, and nickel, due to their safety and availability. More specifically, examples include palladium-carbon (Pd / C), platinum-carbon (Pt / C), rhodium-carbon (Rh / C), rhodium-carbon (Rh / C), nickel-diatomaceous earth (Ni / diatomaceous earth), etc., with palladium-carbon (Pd / C) being particularly preferred.

[0029] In the step of reacting the above-mentioned ether having 16 to 48 carbon atoms with hydrogen, it is preferable to use the above-mentioned metals of groups 8 to 10 of the periodic table in an amount of 0.1 to 1% by mass relative to the mass of the above-mentioned ether having 16 to 48 carbon atoms, from the viewpoint of suitably carrying out the reaction to obtain an alkane from the above-mentioned ether having 16 to 48 carbon atoms. The metals of groups 8 to 10 of the periodic table are preferably present in an amount of 0.2% by mass or more, and more preferably 0.3% by mass or more, relative to the mass of the ethers having 16 to 48 carbon atoms.

[0030] (Ethers with 16 to 48 carbon atoms) Specific examples of ethers with 16 to 48 carbon atoms include, for example, octyl ether, dodecyl ether, tetradecyl ether, and docosyl ether. These ethers used as raw materials can be used individually or in combination of two or more types, and ethers produced as by-products from two alcohols with different carbon chain lengths can also be used.

[0031] Furthermore, the method for producing alkanes according to the present invention can produce alkanes with the same number of carbon atoms as ethers with 16 to 48 carbon atoms.

[0032] (others) In the step of reacting the above-mentioned ether having 16 to 48 carbon atoms with hydrogen, a solvent may be used, but it is preferable not to use a solvent. If a solvent is used, it is necessary to use a solvent whose boiling point is equal to or higher than the reaction temperature of the reaction in which the alkane is obtained from the above-mentioned ether having 16 to 48 carbon atoms.

[0033] The process of reacting the above-mentioned ether with 16 to 48 carbon atoms with hydrogen can be carried out in a closed system or a flow system, but in either system, it is necessary to remove the water produced by the reaction of the above-mentioned ether with 16 to 48 carbon atoms with hydrogen. For example, in the case of a closed system, purging operations are performed as needed by opening and closing valves to remove water produced by the reaction of the above-mentioned ether with 16 to 48 carbon atoms with hydrogen. In the case of a flow system, the reactor is an open system, and hydrogen is continuously supplied while the water produced by the reaction of the ether with 16 to 48 carbon atoms with hydrogen, as well as the hydrogen not used in the reaction, is released out of the system. In the case of a flow system, it is necessary to adjust the hydrogen flow rate so that the ether used as a starting material in the reaction to obtain alkanes from the above-mentioned ethers with 16 to 48 carbon atoms is not released outside the system.

[0034] The equipment used in the process of reacting the above-mentioned ether with 16 to 48 carbon atoms with hydrogen is not particularly limited, and any known equipment can be appropriately selected.

[0035] After the above step of reacting ethers with 16 to 48 carbon atoms with hydrogen, purification may be performed. The above purification methods include filtering the catalyst used in the reaction process between the ether with 16 to 48 carbon atoms and hydrogen, and purifying the crude material after filtration by distillation. The purification method described above is not particularly limited, and any known method may be used.

[0036] (Analysis method) The production of alkanes by the present invention can be confirmed by gas chromatography analysis (GC). As for specific methods, the methods described in the examples of this specification may be used.

[0037] The present invention provides a method for producing alkanes that allows for the production of alkanes with high conversion rates and selectivity. "Conversion rate" refers to the amount of ether consumed as a raw material. The conversion rate can be expressed by the following formula. Conversion rate (%) = 100 (%) - Percentage of ether used as a raw material remaining after the reaction of ethers with 16-48 carbon atoms with hydrogen (%) If the ether used as a raw material is completely consumed, the conversion rate will be 100%. The percentage of the ether used as a raw material remaining after the reaction between ethers with 16 to 48 carbon atoms and hydrogen can be confirmed by GC.

[0038] Furthermore, "selectivity" refers to the proportion of the conversion rate that is accounted for by the target substance. The target substance is a straight-chain alkane obtained from the ether used as a raw material. Selectivity can be expressed by the following formula. Selection rate (%) = <[Percentage of target product (%)] / (Conversion rate)> × 100

[0039] In the method for producing alkanes of the present invention, the conversion rate is preferably 5% or more. The above conversion rate is more preferably 15% or more, even more preferably 30% or more, even more preferably 50% or more, particularly preferably 70% or more, particularly more preferably 90% or more, and most preferably 100%.

[0040] In the method for producing alkanes of the present invention, the selectivity is preferably 25% or more. The above selection rate is more preferably 35% or more, even more preferably 60% or more, even more preferably 70% or more, particularly preferably 80% or more, particularly preferably 90% or more, even more preferably 95% or more, and most preferably 100%.

[0041] This specification discloses the following: (1) The present disclosure is a method for producing alkanes from ethers having 16 to 48 carbon atoms, comprising the step of reacting ethers having 16 to 48 carbon atoms with hydrogen in the presence of a zeolite catalyst and a metal of groups 8 to 10 of the periodic table, at a reaction temperature of 150°C or higher, a reaction time of 3 hours or higher, and a hydrogen pressure of 0 MPa or higher in gauge pressure, wherein the zeolite catalyst is one selected from H-beta type, H-ZSM-5 type, and HY type, and the molar ratio of silica (SiO2) to alumina (Al2O3) (SiO2 / Al2O3) is 5.5 to 40. Disclosure (2) is a method for producing an alkane according to Disclosure (1), wherein the reaction temperature is 180°C to 230°C. Disclosure (3) is a method for producing an alkane according to Disclosure (1) or (2), wherein the reaction time is 8 hours or less. Disclosure (4) is a method for producing an alkane according to any one of Disclosures (1) to (3), wherein the hydrogen pressure is 3.0 MPa or less in gauge pressure. Disclosure (5) is a method for producing an alkane according to any one of Disclosures (1) to (4), wherein the metal of Groups 8 to 10 of the periodic table is at least one selected from the group consisting of palladium, ruthenium, platinum, rhodium, and nickel. This disclosure (6) states that the zeolite catalyst is of the H-beta type or HY type and is used in an amount of 1% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms. The metals of Groups 8 to 10 of the periodic table are palladium or platinum, and the method for producing alkanes according to any one of paragraphs (1) to (5) of this disclosure is to use 0.01% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms. [Examples]

[0042] The present invention will be further described in detail below with reference to examples, but the present invention is not limited to these examples. Compounds not specifically mentioned were used as reagents.

[0043] (Zeolite catalyst) • 822HOA (HSZ-800 series, 822HOA type, manufactured by Tosoh Corporation) • 620HOA (HSZ-600 series, 620HOA type, manufactured by Tosoh Corporation) • 660HOA (HSZ-600 series, 660HOA type, manufactured by Tosoh Corporation) • 320HOA (HSZ-300 series, 320HOA type, manufactured by Tosoh Corporation) • 360HUA (HSZ-300 series, 360HUA type, manufactured by Tosoh Corporation) • 931HOA (HSZ-900 series, 931HOA type, manufactured by Tosoh Corporation) • 940HOA (HSZ-900 series, 940HOA type, manufactured by Tosoh Corporation) Tables 1-6 show the crystal forms and the molar ratio (SiO2 / Al2O3) of silica (SiO2) to alumina (Al2O3). The above molar ratio (SiO2 / Al2O3) was obtained by referring to catalog values. Furthermore, H-MOR indicates that the crystal structure is mordenite type and the cations constituting the zeolite are hydrogen, while HY indicates that the crystal structure is Y type and the cations constituting the zeolite are hydrogen. Furthermore, the usage amounts (mass%) listed in Tables 1-6 represent the amount (mass%) of zeolite catalyst used relative to the mass of ethers with 16-48 carbon atoms. (Metals in Groups 8-10 of the Periodic Table) • Pd / C (Palladium-Carbon, manufactured by N.E. Chemcat Corporation) • Ru / C (Ruthenium-carbon, manufactured by N.E. Chemcat) • Pt / C (Platinum-Carbon, manufactured by N.E. Chemcat) • Rh / C (Rhodium-carbon, manufactured by N.E. Chemcat) • Ni / diatomaceous earth (nickel-diatomaceous earth, manufactured by JGC Catalysts & Chemicals Co., Ltd.) The usage amounts (mass%) listed in Tables 1-6 represent the usage amounts (mass%) of metals from groups 8-10 of the periodic table relative to the mass of ethers with 16-48 carbon atoms. Note that the metals in groups 8-10 of the periodic table mentioned above all have a metal load of 5% and are in dry form. (Ethers with 16 to 48 carbon atoms) • C8OC8 (a carbon-16 ether, manufactured by Tokyo Chemical Industry Co., Ltd.) ·C 12 OC 12 (Dodecyl ether) ·C 14 OC 14 (Tetradecyl ether) ·C 22 OC 22 (Docosyl ether) For the dodecyl ether, 10 g of 1-dodecanol (Conol 20P, manufactured by Shin Nippon Rika Co., Ltd.) and 0.5 g of p-toluenesulfonic acid (manufactured by Kounan Chemical Co., Ltd.) were added as raw materials, and a stirring stone was added. Dehydration condensation was carried out under conditions of stirring speed of 300 rpm and 200°C. The reaction was stopped when the target product exceeded 60% by GC analysis, and the crude product after the reaction was recrystallized twice in xylene to synthesize dodecyl ether with a purity of 98% or more and a yield of approximately 30%. The synthesis of tetradecyl ether was carried out in the same manner as for dodecyl ether, except that the starting material was replaced with 1-tetradecanol (Conol 1495, manufactured by Shin-Nippon Rika Co., Ltd.), and the synthesis of docosyl ether was carried out in the same manner as for dodecyl ether, except that the starting material was replaced with 1-docosanol (Conol 1495, manufactured by Shin-Nippon Rika Co., Ltd.).

[0044] (Comparative Example 1) 2 g of dodecyl ether (5.6 mmol; synthetic), 0.2 g of H-MOR type (Tosoh Corporation; HSZ-600 series, 620HOA type), and 6 mg of 5% Pd / C (N.E. Chemcat Corporation; dry product) were introduced into a stirrable pressure vessel and heated to a reaction temperature of 180°C under a stirring speed of 1000 rpm. The initial pressure was set so that the hydrogen pressure would be 0.1 MPa when the reaction temperature reached 180°C. For 4 hours from the start of the reaction, the reactor was purged every 30 minutes through the discharge valve attached to the reactor until the gauge pressure inside the reactor reached 0 MPa, and then hydrogen was supplied to bring the pressure inside the reactor to 0.1 MPa. After the reaction was complete, the product was cooled, removed, and filtered.

[0045] (Comparative Examples 2-5) The alkanes were produced in the same manner as in Comparative Example 1, except for the change in the configuration shown in Table 1.

[0046] (Example 1) 2 g of dodecyl ether (5.6 mmol; synthetic), 0.2 g of H-ZSM-5 type (Tosoh Corporation; HSZ-800 series, 822HOA type), and 6 mg of 5% Pd / C (N.E. Chemcat Corporation; dry product) were introduced into a stirrable pressure vessel and heated to a reaction temperature of 180°C under a stirring speed of 1000 rpm. The initial pressure was set so that the hydrogen pressure would be 0.1 MPa when the reaction temperature reached 180°C. For 4 hours from the start of the reaction, the reactor was purged every 30 minutes through the discharge valve attached to the reactor until the gauge pressure inside the reactor reached 0 MPa, and then hydrogen was supplied to bring the pressure inside the reactor to 0.1 MPa. After the reaction was complete, the product was cooled, removed, and filtered. A yield of 1.9 g of reaction product was obtained.

[0047] (Examples 2-28) Alkanes were produced in the same manner as in Example 1, except that the reaction temperature, hydrogen pressure, reaction time, catalyst system used, and ethers with 16 to 48 carbon atoms were changed as shown in Tables 1 to 6. Note that the hydrogen pressures listed in Tables 1 to 6 are gauge pressure values.

[0048] (GC analysis) In GC, the catalyst was removed from the products obtained in each example, comparative example, and reference example by filtration, and the crude material after filtration was used as the measurement sample in a 1% by mass hexane or xylene solution. The GC measurement conditions were as follows. The measurements were performed as follows depending on the number of carbon atoms in the ether used as the raw material. The conversion rate and selection rate were calculated using the method described herein. A conversion rate of 5% or higher and a selection rate of 25% or higher were judged as passing, a conversion rate of 5% or higher and a selection rate of 25% or higher were marked with "△", a conversion rate of 5% or higher and a selection rate of 35% or higher were marked with "〇", a conversion rate of 15% or higher and a selection rate of 60% or higher were marked with "◎", and a failure was marked with "×". <Measurement conditions> <Measurement conditions for GC analysis of carbon-16 ethers> Model: Gas chromatograph GC-2014 (manufactured by Shimadzu Corporation) Detector: FID, 335℃ Column: DB-1 (30m x 0.25mmφ x 0.25μm) Column temperature: 40℃ Injection temperature: 335℃ Carrier gas: Helium (linear velocity: 40 cm / sec) Injection volume: 1.0 μl (split ratio: 50) <Measurement conditions for GC analysis of 24- and 28-CCA ethers> Model: Gas chromatograph GC-2014 (manufactured by Shimadzu Corporation) Detector: FID, 335℃ Column: DB-1 (30m x 0.25mmφ x 0.25μm) Column temperature: 70℃ Injection temperature: 335℃ Carrier gas: Helium (linear velocity: 40 cm / sec) Injection volume: 1.0 μl (split ratio: 50) <Measurement conditions for GC analysis of ethers with 44 or more carbon atoms> Model: Gas chromatograph GC-2014 (manufactured by Shimadzu Corporation) Detector: FID, 335℃ Column: DB-1 (30m x 0.25mmφ x 0.25μm) Column temperature: 100℃ Injection temperature: 335℃ Carrier gas: Helium (linear velocity: 38 cm / sec) Injection volume: 1.0 μl (split ratio: 50)

[0049] [Table 1]

[0050] [Table 2]

[0051] [Table 3]

[0052] [Table 4]

[0053] [Table 5]

[0054] [Table 6]

[0055] From the above examples, it was confirmed that the method for producing alkanes of the present invention proceeds at a lower reaction temperature (150-230°C) than conventional methods for producing alkanes, suppresses the formation of by-products such as ethers, allows the use of ethers with chain lengths exceeding C2 as raw materials, and exhibits excellent conversion rate and selectivity. [Industrial applicability]

[0056] The present invention provides a method for producing alkanes in which the reaction proceeds at a low reaction temperature, suppresses the formation of by-products such as ethers, allows the use of ethers with chain lengths exceeding C2 as raw materials, and exhibits excellent conversion rate and selectivity. The manufactured alkanes can be used in a wide range of applications, including as solvents in chemical reactions, paints, and toiletries.

Claims

1. A method for producing alkanes from ethers having 16 to 48 carbon atoms, The process involves reacting an ether with 16 to 48 carbon atoms with hydrogen in the presence of a zeolite catalyst and metals from groups 8 to 10 of the periodic table, under conditions of a reaction temperature of 150°C or higher, a reaction time of 3 hours or higher, and a hydrogen pressure of 0 MPa or higher in gauge pressure. The zeolite catalyst is one selected from H-beta type, H-ZSM-5 type, and H-Y type, and contains silica (SiO ２ ) and alumina (Al ２ O ３ ) molar ratio (SiO ２ / Al ２ O ３ A method for producing alkanes in which the ratio is 5.5 to 40.

2. The method for producing an alkane according to claim 1, wherein the reaction temperature is 180°C to 230°C.

3. The method for producing an alkane according to claim 1 or 2, wherein the reaction time is 8 hours or less.

4. The method for producing an alkane according to claim 1 or 2, wherein the hydrogen pressure is 3.0 MPa or less in gauge pressure.

5. The method for producing an alkane according to claim 1 or 2, wherein the metal of Groups 8 to 10 of the periodic table is at least one selected from the group consisting of palladium, ruthenium, platinum, rhodium, and nickel.

6. The zeolite catalyst is of the H-beta type or H-Y type, and is used in an amount of 1% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms. The method for producing an alkane according to claim 1 or 2, wherein the metal of group 8 to 10 of the periodic table is palladium or platinum, and is used in an amount of 0.01% by mass or more relative to the mass of the ether having 16 to 48 carbon atoms.

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