Method for producing alkane

Abstract

To provide a method for producing an alkane in which a reaction proceeds at a low reaction temperature and reaction pressure, carbon loss from an alcohol is suppressed, and the conversion rate and selectivity are excellent. Provided is a method for producing an alkane from a C8-24 alcohol, the method comprising a step for reacting a C8-24 alcohol with hydrogen in the presence of a zeolite catalyst and a periodic table group 8-10 noble metal at a reaction temperature of 160°C or higher and a hydrogen pressure of 3 MPa or lower by gauge pressure. The zeolite catalyst is an H-beta type or an H-ZSM -5 type, and the molar ratio (SiO2 / Al2O3) of silica (SiO2) and alumina (Al2O3) is 20-35.

Description

Alkane production method

[0001] The present invention relates to a method for producing an alkane, and to an alkane.

[0002] Methods for producing alkanes from alcohols, which are abundant in nature, have been studied. Alkanes are chemically and thermally stable chemical substances and are used in a wide range of fields, including as solvents for chemical reactions, paints, and cosmetics.

[0003] Most of the alkanes currently in use are derived from petroleum, which has the advantage of being cheap and readily available.

[0004] However, the use of petroleum-derived alkanes is thought to be one of the causes of the rise in global carbon dioxide concentrations, and therefore there is a demand for the production of alkanes from biomass-derived raw materials, primarily plants.

[0005] Oils and fats such as coconut oil, palm oil, castor oil, sunflower oil, and rapeseed oil are widely used as plant-derived raw materials, and higher alcohols with 8 to 24 carbon atoms are produced worldwide using these as raw materials. Therefore, there is a demand for producing alkanes using higher alcohols with 8 to 24 carbon atoms as raw materials.

[0006] For example, Patent Document 1 discloses a method for producing linear saturated alkanes from primary alcohols having one more carbon atom in the carbon chain than the alkane by reductive dehydroxymethylation of the primary alcohol in the presence of hydrogen and a catalyst at a temperature of 100 to 300°C and a pressure of 1 to 250 bar while removing water formed during the reaction, the method being characterized in that a fatty alcohol containing 8 to 24 carbon atoms is used as the primary alcohol.

[0007] Special Publication No. 2009-519264

[0008] In the method described in Patent Document 1, the most preferable reaction temperature range is 220 to 260°C and the most preferable reaction pressure range is 10 to 50 bar, and a method for obtaining alkanes at lower reaction temperatures and reaction pressures has been desired.

[0009] Furthermore, in the method described in Patent Document 1, an alkane having one carbon atom reduced is produced from a primary alcohol. Therefore, methane is generated along with the production of the alkane, and it is necessary to recover the methane.

[0010] Therefore, the present invention provides a method for producing alkanes in which the reaction proceeds at a lower reaction temperature and reaction pressure than those of the method described in Patent Document 1, carbon loss from alcohol is suppressed, and the method has excellent conversion and selectivity.

[0011] As a result of extensive research, the present inventors have found that by reacting alcohol with hydrogen using a specific zeolite catalyst and a noble metal, alkanes can be produced from alcohol without carbon reduction at lower reaction temperatures and pressures than conventional methods, and furthermore, the conversion rate and selectivity are excellent, thereby completing the present invention.

[0012] That is, the present invention provides a method for producing an alkane from an alcohol having 8 to 24 carbon atoms, the method comprising the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen in the presence of a zeolite catalyst and a noble metal of Groups 8 to 10 of the periodic table at a reaction temperature of 160°C or higher and a hydrogen pressure of 3 MPa or lower in gauge pressure, wherein the zeolite catalyst is an H-beta type or H-ZSM-5 type, and silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ ) is 20 to 35.

[0013] In the method for producing an alkane of the present invention, the step of reacting an alcohol having 8 to 24 carbon atoms with hydrogen preferably uses the zeolite catalyst in an amount of 1 to 20 mass % relative to the mass of the alcohol having 8 to 24 carbon atoms. In the method for producing an alkane of the present invention, the step of reacting an alcohol having 8 to 24 carbon atoms with hydrogen preferably uses a noble metal of Groups 8 to 10 of the Periodic Table in an amount of 0.1 to 1 mass % relative to the mass of the alcohol having 8 to 24 carbon atoms. The reaction temperature is preferably 180°C or higher. The hydrogen pressure is preferably 1.0 MPa or lower in gauge pressure. The hydrogen pressure is preferably 0 MPa or higher in gauge pressure. The reaction time in the step of reacting an alcohol having 8 to 24 carbon atoms with hydrogen is preferably 2 to 8 hours. The zeolite catalyst is preferably a catalyst containing silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ ) is preferably 24 to 30. The noble metal of Groups 8 to 10 of the periodic table is preferably at least one selected from the group consisting of palladium, ruthenium, platinum, and rhodium. The present invention also relates to an alkane having a natural origin index of 100% and a content of alkanes having a branched structure of 5% by mass to 70% by mass of all alkanes.

[0014] The present invention provides a method for producing alkanes, which allows the reaction to proceed at lower reaction temperatures and reaction pressures, suppresses carbon loss from alcohols, and enables the production of alkanes with excellent conversion and selectivity.

[0015] The method for producing an alkane of the present invention is a method for producing an alkane from an alcohol having 8 to 24 carbon atoms, and includes a step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen in the presence of a zeolite catalyst and a noble metal of Groups 8 to 10 of the periodic table at a reaction temperature of 160°C or higher and a hydrogen pressure of 3 MPa or lower in gauge pressure, wherein the zeolite catalyst is an H-beta type or H-ZSM-5 type, and silica (SiO ２ ) and alumina (Al ２O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ ) is 20 to 35. Each component of the method for producing alkanes of the present invention will be described in detail below.

[0016] <Step of Reacting Alcohol Having 8 to 24 Carbon Atoms with Hydrogen> The method for producing an alkane of the present invention includes a step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen in the presence of a zeolite catalyst and a noble metal of Groups 8 to 10 of the periodic table, under conditions of a reaction temperature of 160°C or higher and a hydrogen pressure of 3 MPa or lower in gauge pressure.

[0017] (Reaction Temperature) In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, the reaction temperature is 160°C or higher. When the reaction temperature is within the above range, the reaction proceeds to produce an alkane from the alcohol having 8 to 24 carbon atoms. The reaction temperature is preferably 180°C or higher. The upper limit of the reaction temperature is not particularly limited, but is, for example, 200°C.

[0018] (Hydrogen Pressure) In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, the hydrogen pressure is 3 MPa or less in gauge pressure. By setting the hydrogen pressure within the above range, the reaction proceeds to obtain an alkane from the alcohol having 8 to 24 carbon atoms. The hydrogen pressure is preferably 1.5 MPa or less in gauge pressure, more preferably 1.0 MPa or less, even more preferably 0.5 MPa or less, and particularly preferably 0.3 MPa or less. The lower limit of the hydrogen pressure is preferably 0 MPa in gauge pressure. The reaction to obtain an alkane from the alcohol having 8 to 24 carbon atoms proceeds sufficiently even when the hydrogen pressure is normal pressure. The reaction may also be carried out by reducing the hydrogen pressure within a range that does not impair the effect. 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 alcohol having 8 to 24 carbon atoms with hydrogen, the reaction time is preferably 2 to 8 hours. By keeping the reaction time within this range, the reaction of obtaining an alkane from the alcohol having 8 to 24 carbon atoms proceeds sufficiently. From the viewpoint of selectivity, the reaction time is more preferably 3 to 4 hours. The reaction time refers to the time from when the reaction temperature described above is reached to when the reaction is completed.

[0020] (Zeolite Catalyst) In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, a zeolite catalyst is used.

[0021] The zeolite catalyst is an H-beta type or an H-ZSM-5 type. The H-beta type means that the crystalline structure is a beta type (BEA type) and the cations constituting the zeolite are hydrogen, while the H-beta type means that the crystalline structure is a ZSM-5 type (MFI type) and the cations constituting the zeolite are hydrogen.

[0022] The zeolite catalyst is silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ ) is 20 to 35. ２ / Al ２ O ３ When the molar ratio (SiO ２ / Al ２ O ３ ) is preferably 24 to 30, more preferably 24 to 28.

[0023] When the zeolite catalyst is of the H-beta type, the molar ratio (SiO ２ / Al ２ O ３ ) is most preferably 28. A commercially available product of such a zeolite catalyst is the HSZ-900 series 931HOA type (manufactured by Tosoh Corporation).

[0024] In addition, when the zeolite catalyst is an H-ZSM-5 type, the molar ratio (SiO ２ / Al ２ O ３ ) is most preferably 24 to 25. Examples of commercially available zeolite catalysts of this type include the HSZ-800 series 822HOA type (manufactured by Tosoh Corporation).

[0025] In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, the zeolite catalyst is preferably used in an amount of 1 to 20% by mass relative to the mass of the alcohol having 8 to 24 carbon atoms, from the viewpoint of favorably proceeding with the reaction that produces an alkane from the alcohol having 8 to 24 carbon atoms. When the zeolite catalyst is an H-beta type, it is preferably used in an amount of 2% by mass or more relative to the mass of the alcohol having 8 to 24 carbon atoms. When the zeolite catalyst is an H-ZSM-5 type, it is preferably used in an amount of 5% by mass or more relative to the mass of the alcohol having 8 to 24 carbon atoms.

[0026] (Noble Metals of Groups 8 to 10 of the Periodic Table) In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, noble metals of Groups 8 to 10 of the Periodic Table are used.

[0027] Examples of the noble metals of Groups 8 to 10 of the periodic table include ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, and platinum.

[0028] Among these, at least one selected from the group consisting of palladium, ruthenium, platinum, and rhodium is preferred from the viewpoint of safety and availability. More specifically, palladium-carbon (Pd / C), palladium-alumina (Pd / Al ２ O ３ ), ruthenium-carbon (Ru / C), ruthenium-alumina (Ru / Al ２ O ３ ), rhodium-carbon (Rh / C), platinum-carbon (Pt / C), rhodium-carbon (Rh / C), etc., with palladium-carbon (Pd / C) being particularly preferred.

[0029] In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, the noble metal of Groups 8 to 10 of the periodic table is preferably used in an amount of 0.1 to 1 mass % relative to the mass of the alcohol having 8 to 24 carbon atoms, from the viewpoint of favorably proceeding the reaction that produces an alkane from the alcohol having 8 to 24 carbon atoms. The noble metal of Groups 8 to 10 of the periodic table is preferably 0.2 mass % or more, and more preferably 0.3 mass % or more, relative to the mass of the alcohol having 8 to 24 carbon atoms.

[0030] (Alcohols Having 8 to 24 Carbon Atoms) The alcohols having 8 to 24 carbon atoms are preferably aliphatic primary alcohols having 8 to 24 carbon atoms. Specific examples include 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-heptadecanol, 1-octadecanol, 1-nonadecanol, 1-eicosanol, and 1-docosanol. These alcohols used as raw materials can be used alone or in combination of two or more.

[0031] In addition, the method for producing an alkane of the present invention can produce an alkane having the same number of carbon atoms as an alcohol having 8 to 24 carbon atoms.

[0032] (Others) In the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, a solvent may be used, but it is preferable not to use a solvent. When using the solvent, it is necessary to use a solvent whose boiling point is equal to or higher than the reaction temperature of the reaction in which an alkane is obtained from the alcohol having 8 to 24 carbon atoms.

[0033] The step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen may be carried out in a closed system or a flow system. In either system, however, it is necessary to remove the water produced by the reaction of the alcohol having 8 to 24 carbon atoms with hydrogen. For example, in the case of a closed system, a purging operation is performed by opening and closing a valve as appropriate to remove the water produced by the reaction of the alcohol having 8 to 24 carbon atoms with hydrogen. In the case of a flow system, the reactor is an open system, and while hydrogen is continuously supplied, the water produced by the reaction of the alcohol having 8 to 24 carbon atoms with hydrogen and the hydrogen not used in the reaction are released outside the system. In the case of a flow system, it is necessary to adjust the hydrogen flow rate so that the alcohol used as a raw material during the reaction to obtain an alkane from the alcohol having 8 to 24 carbon atoms is not released outside the system.

[0034] The equipment used in the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen is not particularly limited, and any known equipment may be appropriately selected.

[0035] After the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, purification may be carried out. Examples of the purification include filtering the catalyst used in the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen, and purifying the crude product after filtration by distillation. The method of purification is not particularly limited, and any known method may be used.

[0036] (Analysis Method) It can be confirmed by gas chromatography (GC) that alkanes have been produced by the alkane production method of the present invention. In addition, the contents of linear alkanes and branched alkanes can be confirmed by GC. Specific methods may be those described in the Examples of this specification.

[0037] The alkane production method of the present invention can produce alkanes with high conversion and selectivity. The "conversion" refers to the amount of alcohol consumed as a raw material. The conversion can be expressed by the following formula: Conversion (%) = 100 (%) - Proportion (%) of the alcohol used as a raw material remaining after the reaction of the alcohol having 8 to 24 carbon atoms with hydrogen. When the alcohol used as a raw material is completely consumed, the conversion is 100%. The proportion (%) of the alcohol used as a raw material remaining after the reaction of the alcohol having 8 to 24 carbon atoms with hydrogen can be confirmed by GC.

[0038] Furthermore, "selectivity" refers to the proportion of the target product in the conversion rate. The target product is an alkane that has not been reduced in carbon from the alcohol used as the raw material. The selectivity can be expressed by the following formula: Selectivity (%) = <[Proportion of target product (%)] / (Conversion rate)> x 100

[0039] In the alkane production method of the present invention, the conversion rate is 40% or more, preferably 50% or more, more preferably 60% or more, even more preferably 70% or more, even more preferably 80% or more, particularly preferably 90% or more, and most preferably 100%.

[0040] In the alkane production method of the present invention, the selectivity is 55% or more, preferably 60% or more, more preferably 70% or more, even more preferably 80% or more, even more preferably 90% or more, particularly preferably 95% or more, and most preferably 100%.

[0041] (Alkane) In the alkane production method of the present invention, by using a biomass-derived raw material, it is possible to obtain alkanes with a natural origin index of 100%. That is, the alkane production method of the present invention can obtain alkanes with a natural origin index of 100% and in which the content of alkanes having a branched structure relative to the total amount of alkanes is 5% by mass or more and 70% by mass or less. Alkanes obtained by such an alkane production method of the present invention are also encompassed by the present invention.

[0042] In this specification, the natural origin index is a value calculated in accordance with ISO 16128, and indicates the proportion of natural raw materials derived from plants, animals, algae, microorganisms such as bacteria and fungi, and minerals. The alkane of the present invention has a natural origin index of 100%, meaning that all raw materials are derived from natural raw materials.

[0043] The present specification discloses the following: The present disclosure (1) is a method for producing an alkane from an alcohol having 8 to 24 carbon atoms, comprising reacting the alcohol having 8 to 24 carbon atoms with hydrogen in the presence of a zeolite catalyst and a noble metal of Groups 8 to 10 of the periodic table at a reaction temperature of 160°C or higher and a hydrogen pressure of 3 MPa or lower in gauge pressure, wherein the zeolite catalyst is an H-beta type or H-ZSM-5 type, and silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３) is 20 to 35. The present disclosure (2) is the method for producing an alkane according to the present disclosure (1), wherein the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen uses the zeolite catalyst in an amount of 1 to 20 mass% relative to the mass of the alcohol having 8 to 24 carbon atoms. The present disclosure (3) is the method for producing an alkane according to the present disclosure (1) or (2), wherein the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen uses a noble metal of Groups 8 to 10 of the periodic table in an amount of 0.1 to 1 mass% relative to the mass of the alcohol having 8 to 24 carbon atoms. The present disclosure (4) is the method for producing an alkane according to any one of the present disclosures (1) to (3), wherein the reaction temperature is 180°C or higher. The present disclosure (5) is the method for producing an alkane according to any one of the present disclosures (1) to (4), wherein the hydrogen pressure is 1.0 MPa or lower in gauge pressure. The present disclosure (6) is the method for producing an alkane according to any one of the present disclosures (1) to (5), wherein the hydrogen pressure is 0 MPa or more in gauge pressure. The present disclosure (7) is the method for producing an alkane according to any one of the present disclosures (1) to (6), wherein the reaction time in the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen is 2 to 8 hours. The present disclosure (8) is the method for producing an alkane according to any one of the present disclosures (1) to (6), wherein the zeolite catalyst is a silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ The method for producing an alkane according to any one of the present disclosures (1) to (7), wherein the noble metal of Groups 8 to 10 of the periodic table is at least one selected from the group consisting of palladium, ruthenium, platinum, and rhodium. The present disclosure (10) is an alkane having a natural origin index of 100% and a content of alkanes having a branched structure of 5% by mass or more and 70% by mass or less relative to the total amount of alkanes.

[0044] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Reagents were used for compounds not specifically mentioned.

[0045] (Zeolite catalyst) 822HOA (HSZ-800 series, 822HOA type, manufactured by Tosoh Corporation) 840HOA (HSZ-800 series, 840HOA 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) 360HOA (HSZ-300 series, 360HOA 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) Zeolite catalyst (manufactured by N.E. Chemcat Corporation) Note that the crystal form, silica (SiO ２ ) and alumina (Al ２ O ３ ) and the molar ratio (SiO ２ / Al ２ O ３ ) is shown in the above molar ratio (SiO ２ / Al ２ O ３ ) refers to the catalogue value. H-MOR means that the crystal structure is mordenite type and the cations constituting the zeolite are hydrogen, and H-Y means that the crystal structure is Y type and the cations constituting the zeolite are hydrogen. The amount (mass %) used in Tables 1 to 4 means the amount (mass %) of zeolite catalyst used relative to the mass of alcohol having 8 to 24 carbon atoms. (Noble metals of Groups 8 to 10 of the periodic table) Pd / C (palladium-carbon, manufactured by N.E. Chemcat Corporation) Pd / Al ２ O ３(Palladium-alumina, manufactured by N.E. Chemcat Corporation) Ru / C (Ruthenium-carbon, manufactured by N.E. Chemcat Corporation) Pt / C (Platinum-carbon, manufactured by N.E. Chemcat Corporation) Rh / C (Rhodium-carbon, manufactured by N.E. Chemcat Corporation) The amounts (mass %) used in Tables 1 to 4 refer to the amounts (mass %) used of the noble metals from Groups 8 to 10 of the periodic table relative to the mass of the alcohol having 8 to 24 carbon atoms. Note that the noble metals from Groups 8 to 10 of the periodic table all have a metal loading of 5% and are dry products. (Alcohols having 8 to 24 carbon atoms) C ８ OH (1-octanol) (Conol 10WS: plant-derived (biomass-derived raw material), manufactured by New Japan Chemical Co., Ltd.) １０ OH(1-decanol) (Conol 1098: plant-derived, manufactured by New Japan Chemical Co., Ltd.) １２ OH(1-dodecanol) (Conol 20P: plant-derived, manufactured by New Japan Chemical Co., Ltd.) １４ OH(1-tetradecanol) (Conol 1495: plant-derived, manufactured by New Japan Chemical Co., Ltd.) １６ OH (1-hexadecanol) (Conol 1695: plant-derived, manufactured by New Japan Chemical Co., Ltd.) C １８ OH (1-octadecanol) (Conol 30SS: plant-derived, manufactured by New Japan Chemical Co., Ltd.) C ２２ OH (1-docosanol) (Tokyo Chemical Industry Co., Ltd.) C １２ OH (75% by mass)・C １４ OH (25% by mass) (Conol C1275: plant-derived, manufactured by New Japan Chemical Co., Ltd.)

[0046] (Comparative Example 1) 100 g of 1-dodecanol (0.54 mol; manufactured by New Japan Chemical Co., Ltd.) and 5 g of H-ZSM-5 type (manufactured by Tosoh Corporation; HSZ-800 series, 822HOA type) were introduced into a stirrer-capable pressure vessel and heated to a reaction temperature of 180°C under conditions of a stirring speed of 1000 rpm. Once the reaction temperature reached 180°C, the reactor was purged once every 20 minutes for 4 hours until the gauge pressure reached 0 MPa. Subsequently, the product was cooled, removed, and filtered. A reaction product yield of 96 g was obtained.

[0047] Comparative Examples 2 to 8 and 17 Alkanes were produced in the same manner as in Comparative Example 1, except that the catalyst systems used were changed as shown in Tables 1 and 2.

[0048] Example 1 100 g of 1-dodecanol (0.54 mol; manufactured by New Japan Chemical Co., Ltd.), 5 g of H-ZSM-5 type (manufactured by Tosoh Corporation; HSZ-800 series, 822HOA type), and 0.5 g of 5% Pd / C (manufactured by N.E. Chemcat Corporation; dry product) were placed in a stirrer-capable pressure vessel and heated to a reaction temperature of 180°C under conditions of a stirring speed of 1000 rpm. Over a period of 4 hours from the point at which the reaction temperature reached 180°C, the reactor was purged through the attached exhaust valve every time the pressure inside the reactor reached 0.02 MPa until the gauge pressure inside the reactor reached 0 MPa. Hydrogen was then supplied so that the pressure inside the reactor reached 0.1 MPa. The product was then cooled, removed, and filtered. A reaction product yield of 90 g was obtained.

[0049] (Examples 2 to 43, Comparative Examples 9 to 16) Alkanes were produced in the same manner as in Example 1, except that the reaction temperature, hydrogen pressure, reaction time, catalyst system used, and alcohol having 8 to 24 carbon atoms were changed as shown in Tables 1 to 4. The hydrogen pressures shown in Tables 1 to 4 are values ​​measured at gauge pressure.

[0050] (GC Analysis) In GC, the catalyst was removed from the products obtained in each Example and Comparative Example by filtration, and the crude product after filtration was prepared into a 1% by mass hexane solution, which was used as a measurement sample. The GC measurement conditions were as follows. Measurements were performed as follows depending on the carbon number of the alcohol used as the raw material. The conversion rate and selectivity were calculated using the method described herein. Note that a conversion rate of 40% or more and a selectivity of 55% or more were judged to be acceptable. In addition, the contents of linear alkanes and branched alkanes were confirmed by GC. <Measurement conditions> <Measurement conditions for GC for C8 to C10 analysis> Model: Gas chromatograph GC-2014 (Shimadzu Corporation) Detector: FID, 335°C Column: DB-1 (30m x 0.25mmφ x 0.25μm) Column temperature: 40°C Injection temperature: 335°C Carrier gas: Helium (linear velocity: 40cm / sec) Injection volume: 1.0μl (split ratio: 50) <Measurement conditions for GC for C12 to C18 analysis> Model: Gas chromatograph GC-2014 (Shimadzu Corporation) Detector: FID, 335°C Column: DB-1 (30m x 0.25mmφ x 0.25μm) Column temperature: 70°C Injection temperature: 335°C Carrier gas: Helium (linear velocity: 40cm / sec) Injection volume: 1.0 μl (split ratio: 50) <GC measurement conditions for analysis of C20 or higher> Model: Gas chromatograph GC-2014 (Shimadzu Corporation) Detector: FID, 335°C Column: DB-1 (30 m x 0.25 mmφ x 0.25 μm) Column temperature: 100°C Injection temperature: 335°C Carrier gas: Helium (linear velocity: 38 cm / sec) Injection volume: 1.0 μl (split ratio: 50)

[0051]

[0052]

[0053]

[0054]

[0055] From the above examples, it was confirmed that the alkane production method of the present invention allows the reaction to proceed at a lower reaction temperature (160 to 200°C) and reaction pressure (hydrogen pressure of 3.0 MPa or less in gauge pressure) than conventional alkane production methods, suppresses carbon loss from alcohol, and is excellent in conversion and selectivity.

[0056] The alkanes obtained by the alkane production method of the present invention used biomass-derived raw materials, and therefore had a natural origin index of 100%. Furthermore, the alkanes obtained in Example 8 had a branched alkane content of 15% by mass and a linear alkane content of 85% by mass. Furthermore, the alkanes obtained in Example 38 had a branched alkane content of 5% by mass and a linear alkane content of 92% by mass. Furthermore, the alkanes obtained in Example 18 had a branched alkane content of 21% by mass and a linear alkane content of 63% by mass. Further distillation of the alkanes obtained in Example 18 yielded alkanes with a branched alkane content of 66% by mass.

[0057] The method for producing an alkane of the present invention allows the reaction to proceed at low reaction temperatures and pressures, suppresses carbon loss from alcohol, and is excellent in conversion and selectivity. Furthermore, the alkane of the present invention can be used as a cosmetic raw material or a biomass raw material.

Claims

1. A method for producing an alkane from an alcohol having 8 to 24 carbon atoms, comprising a step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen in the presence of a zeolite catalyst and a noble metal of Groups 8 to 10 of the periodic table under conditions of a reaction temperature of 160° C. or higher and a hydrogen pressure of 3 MPa or lower in terms of gauge pressure, the zeolite catalyst being an H-beta type or an H-ZSM-5 type, and silica (SiO ２ ) and alumina (Al ２ O ３ ) molar ratio (SiO ２ / Al ２ O ３ ) is 20 to 35.

2. The method for producing an alkane according to claim 1, wherein the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen uses 1 to 20 mass% of the zeolite catalyst relative to the mass of the alcohol having 8 to 24 carbon atoms.

3. The method for producing an alkane according to claim 1 or 2, wherein the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen uses 0.1 to 1 mass% of a noble metal of Groups 8 to 10 of the periodic table relative to the mass of the alcohol having 8 to 24 carbon atoms.

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

5. A method for producing an alkane according to claim 1 or 2, wherein the hydrogen pressure is 1.0 MPa or less in terms of gauge pressure.

6. The method for producing an alkane according to claim 1 or 2, wherein the hydrogen pressure is 0 MPa or more in terms of gauge pressure.

7. The method for producing an alkane according to claim 1 or 2, wherein the reaction time in the step of reacting the alcohol having 8 to 24 carbon atoms with hydrogen is 2 to 8 hours.

8. The zeolite catalyst is silica (SiO ２ ) and alumina (Al ２ O ３ ) molar ratio (SiO ２ / Al ２ O ３ 3. The method for producing an alkane according to claim 1 or 2, wherein the molar ratio of the alkane to the alkanes is 24 to 30.

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

10. An alkane having a natural origin index of 100% and a content of alkanes having a branched structure of the total amount of alkanes of 5% by mass or more and 70% by mass or less.

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