JP2017141208A - Manufacturing method of unsaturated hydrocarbon and manufacturing method of conjugated diene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of unsaturated hydrocarbon capable of providing unsaturated hydrocarbon from alkane at good efficiency as a novel manufacturing method of unsaturated hydrocarbon.SOLUTION: There is provided a manufacturing method of unsaturated hydrocarbon having a process for containing a raw material gas containing alkane with a dehydrogenation catalyst to obtain a product gas containing at least one kind of unsaturated hydrocarbon selected from the group consisting of olefin and conjugated gas, the dehydrogenation catalyst is a catalyst having carried metal containing the XIV group metal elements and Pt carried on a carrier containing Al and the II group metal element and total acid amount of the carrier measured by an ammonium TPD method is 15 μmol/g or less.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing an unsaturated hydrocarbon and a method for producing a conjugated diene.

  Due to recent motorization centered in Asia, demand for unsaturated hydrocarbons such as butadiene is expected to increase as raw materials for synthetic rubber. Examples of the method for producing butadiene include a method for producing conjugated diene by direct dehydrogenation of n-butane using a dehydrogenation catalyst (Patent Document 1), and a conjugated diene by oxidative dehydrogenation of n-butene. (Patent Documents 2 to 4) are known.

JP 2014-205135 A JP-A-57-140730 JP 60-1139 A JP 2003-220335 A

  With the increase in demand for unsaturated hydrocarbons, development of various methods for producing unsaturated hydrocarbons having different characteristics such as required characteristics, operating costs, reaction efficiency, etc. of production equipment is required.

  An object of the present invention is to provide a method for producing an unsaturated hydrocarbon capable of efficiently obtaining an unsaturated hydrocarbon from an alkane as a novel method for producing an unsaturated hydrocarbon. Another object of the present invention is to provide a method for producing a conjugated diene, which can efficiently obtain a conjugated diene that is expected to increase in demand among unsaturated hydrocarbons.

  The present inventors have found that alkanes can be efficiently converted into unsaturated hydrocarbons by a catalyst in which a specific metal element is supported on a specific support, and the present invention has been completed.

  One aspect of the present invention includes a step of bringing a raw material gas containing an alkane into contact with a dehydrogenation catalyst to obtain a product gas containing at least one unsaturated hydrocarbon selected from the group consisting of an olefin and a conjugated diene. The present invention relates to a method for producing saturated hydrocarbons. In this production method, the dehydrogenation catalyst is a catalyst in which a carrier containing Al and a Group 2 metal element is supported on a carrier metal containing a Group 14 metal element and Pt, and is measured by the ammonia TPD method of the carrier. The total acid amount is 15 μmol / g or less.

  In one embodiment, the total acid amount measured by the ammonia TPD method of the carrier may be 10 μmol / g or less.

  In one embodiment, the Group 14 metal element supported on the support may be Sn.

  In one embodiment, the raw material alkane may be an alkane having 4 to 10 carbon atoms.

  In one embodiment, the alkane may be butane, where the olefin may be butene and the conjugated diene may be butadiene.

  In another aspect of the present invention, a first step of bringing a raw material gas containing alkane into contact with a first dehydrogenation catalyst to obtain a first product gas containing olefin, And a second step of obtaining a second product gas containing a conjugated diene by contacting with the dehydrogenation catalyst. In this production method, the first dehydrogenation catalyst is a catalyst in which a support containing Al and a Group 2 metal element is supported on a support metal containing a Group 14 metal element and Pt, and the ammonia TPD method of the support is used. The total acid amount measured at is 15 μmol / g or less.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of unsaturated hydrocarbon which can obtain unsaturated hydrocarbon efficiently from alkane is provided as a novel manufacturing method of unsaturated hydrocarbon. Moreover, according to this invention, the manufacturing method of conjugated diene which can obtain a conjugated diene from alkane efficiently is provided.

  Hereinafter, a preferred embodiment of the present invention will be described.

  The method for producing an unsaturated hydrocarbon according to the present embodiment includes a product gas containing at least one unsaturated hydrocarbon selected from the group consisting of an olefin and a conjugated diene by bringing a raw material gas containing an alkane into contact with a dehydrogenation catalyst. The process (henceforth a dehydrogenation process) obtained. In the present embodiment, the dehydrogenation catalyst is a catalyst in which a carrier containing Al and a Group 2 metal element is supported on a supported metal containing a Group 14 metal element and Pt. Further, the total acid amount of the carrier measured by the ammonia TPD method is 15 μmol / g or less.

  According to the production method according to this embodiment, by using a dehydrogenation catalyst in which a specific metal is supported on a specific support, an alkane can be reacted at a high conversion rate to obtain an unsaturated hydrocarbon.

  In this embodiment, the source gas contains alkane. The carbon number of the alkane may be the same as the carbon number of the target unsaturated hydrocarbon. The carbon number of the alkane may be, for example, 4 to 10 or 4 to 6.

  For example, the alkane may be a chain or a ring. Examples of the chain alkane include butane, pentane, hexane, heptane, octane, decane, and the like. More specifically, examples of the linear alkane include n-butane, n-pentane, n-hexane, n-heptane, n-octane, and n-decane. Examples of the branched alkane include isobutane, isopentane, 2-methylpentane, 3-methylpentane, 2,3-dimethylpentane, isoheptane, isooctane, and isodecane. Examples of the cyclic alkane include cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, and methylcyclohexane. The source gas may contain one kind of alkane or two or more kinds.

  In the source gas, the partial pressure of alkane may be 1.0 MPa or less, 0.1 MPa or less, or 0.01 MPa or less. By reducing the alkane partial pressure of the source gas, the alkane conversion rate can be further improved.

  The partial pressure of alkane in the raw material gas is preferably 0.001 MPa or more, and more preferably 0.005 MPa or more, from the viewpoint of reducing the reactor size with respect to the raw material flow rate.

  The source gas may further contain an inert gas such as nitrogen or argon. The source gas may further contain steam.

  When the raw material gas contains steam, the steam content is preferably 1.0 mole or more and more preferably 1.5 moles or more with respect to the alkane. By including steam in the raw material gas, the catalyst activity may be more significantly suppressed. In addition, content of a steam may be 50 times mole or less with respect to alkane, for example, Preferably it is 10 times mole or less.

  The source gas may further contain other components such as hydrogen, oxygen, carbon monoxide, carbon dioxide gas, olefins and dienes in addition to the above.

  In the present embodiment, the product gas contains at least one unsaturated hydrocarbon selected from the group consisting of olefins and conjugated dienes. The number of carbon atoms of the olefin and conjugated diene may be the same as the carbon number of the alkane, for example, 4 to 10 or 4 to 6.

  Examples of olefins include butene, pentene, hexene, heptene, octene, nonene, decene and the like, and these may be any isomer. Examples of the conjugated diene include 1,3-butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1,3-nonadiene, and 1,3-decadiene. Etc. The product gas may contain one kind of unsaturated hydrocarbon, and may contain two or more kinds of unsaturated hydrocarbons. For example, the product gas may include olefins and conjugated dienes.

  Below, the dehydrogenation catalyst in this embodiment is explained in full detail.

  The dehydrogenation catalyst is a solid catalyst that catalyzes a dehydrogenation reaction of an alkane, and is a catalyst in which a supported metal containing a Group 14 metal element and Pt is supported on a support containing Al and a Group 2 metal element.

  The Group 2 metal element contained in the support may be at least one selected from the group consisting of Be, Mg, Ca, Sr and Ba.

The support may be, for example, a metal oxide support containing Al and a Group 2 metal element. The metal oxide support may be, for example, a support containing alumina (Al ₂ O ₃ ) and a Group 2 metal oxide, or may be a composite oxide of Al and a Group 2 metal.

  In the support, the molar ratio of the Group 2 metal element to Al (Group 2 metal element / Al) may be, for example, 0.01 or more, and preferably 0.1 or more. Further, the molar ratio of the Group 2 metal element to Al may be, for example, 10 or less, and preferably 2 or less. With such a molar ratio, the acid amount of the carrier is optimized, and side reactions are more significantly suppressed.

  In the present embodiment, the total acid amount of the carrier is 15 μmol / g or less. By using such a carrier, alkane can be converted to an unsaturated hydrocarbon at a high conversion rate. Further, the total acid amount of the carrier is preferably 10 μmol / g or less, and more preferably 6 μmol / g or less. The total acid amount of the carrier may be 0.1 μmol / g or more, or 1.0 μmol / g or more.

  In this specification, the total acid amount of the carrier indicates the total amount of acid points of the carrier measured by the ammonia TPD method. The ammonia TPD method can be carried out, for example, with the apparatus and measurement conditions described in “Niwa; Zeolite, 10, 175 (1993)”.

The specific surface area of the carrier may be, for example, 30 m ² / g or more, and preferably 50 m ² / g or more. Thereby, the effect of increasing the conversion rate of alkane is produced. The specific surface area of the carrier may be, for example, 1000 m ² / g or less, and preferably 500 m ² / g or less. By having such a specific surface area, a carrier having sufficient strength that can be suitably used industrially can be obtained.

  The method for preparing the carrier is not particularly limited, and may be, for example, a coprecipitation method, a deposition method, a kneading method, an impregnation method, a pore filling method, or the like. Among these, the impregnation method or the pore filling method is preferable from the viewpoint of easily obtaining the above-mentioned preferable total acid amount. As a specific example of the impregnation method, for example, a support is prepared by adding alumina to a solution in which an inorganic salt of a Group 2 metal is dissolved, stirring, removing the solvent under reduced pressure, drying and firing. Can do.

  The dehydrogenation catalyst carries a supported metal containing a Group 14 metal element and Pt. The Group 14 metal element may be at least one selected from the group consisting of Ge, Sn, and Pb, and is preferably Sn.

  The amount of the Group 14 metal element supported may be, for example, 0.1 parts by mass or more, preferably 1.0 part by mass or more, with respect to 100 parts by mass of the carrier. Further, the supported amount of the Group 14 metal element may be, for example, 80 parts by mass or less, and preferably 50 parts by mass or less with respect to 100 parts by mass of the carrier. With such a supported amount, catalyst deterioration is further suppressed, and high activity tends to be maintained for a longer period of time.

  The amount of Pt supported may be, for example, 0.01 parts by mass or more with respect to 100 parts by mass of the carrier, and preferably 0.1 parts by mass or more. Further, the amount of Pt supported may be, for example, 5.0 parts by mass or less, preferably 3.0 parts by mass or less, with respect to 100 parts by mass of the carrier. With such a loading amount, the Pt particles formed on the catalyst have a size suitable for the dehydrogenation reaction, and the platinum surface area per unit platinum weight increases, so that a more efficient reaction system can be realized.

  The supporting method of the supporting metal is not particularly limited, and examples thereof include an impregnation method, a deposition method, a coprecipitation method, a kneading method, an ion exchange method, and a pore filling method.

  One aspect of the loading method is shown below. First, a carrier is added to a solution containing a supported metal precursor, and the solution is stirred. Thereafter, the solvent is removed under reduced pressure, and the solid obtained after drying is calcined, whereby the supported metal can be supported on the carrier.

  In the above supporting method, the supporting metal precursor may be, for example, a metal salt or a complex. The metal salt of the supported metal may be, for example, an inorganic salt, an organic acid salt, or a hydrate thereof. Inorganic salts may be, for example, sulfates, nitrates, chlorides, phosphates, carbonates and the like. The organic acid salt may be, for example, acetate, oxalate and the like. The supported metal complex may be, for example, an alkoxide complex or an ammine complex.

  As conditions at the time of stirring, it can be set as stirring temperature 0-60 degreeC and stirring time 10 minutes-24 hours, for example. Moreover, as conditions at the time of drying, a drying temperature can be 100-250 degreeC and a drying time can be 3 hours-24 hours, for example.

  Firing can be performed, for example, in an air atmosphere or an oxygen atmosphere. Firing may be performed in one stage, or may be performed in two or more stages. The firing temperature may be any temperature as long as the precursor of the supported metal can be decomposed, and may be, for example, 200 to 1000 ° C or 400 to 800 ° C. In addition, when performing multi-stage baking, at least one step should just be the said baking temperature. The firing temperature at the other stage may be in the same range as described above, for example, and may be 100 to 200 ° C.

  The dehydrogenation catalyst may further contain a molding aid from the viewpoint of improving moldability. The molding aid may be, for example, a thickener, a surfactant, a water retention material, a plasticizer, a binder material, or the like.

  The shape of the dehydrogenation catalyst is not particularly limited, and may be, for example, a pellet shape, a granule shape, a honeycomb shape, a sponge shape, or the like.

  A dehydrogenation catalyst that has been subjected to a reduction treatment as a pretreatment may be used. The reduction treatment can be performed, for example, by holding the dehydrogenation catalyst at 40 to 600 ° C. in a reducing gas atmosphere. The holding time may be, for example, 0.05 to 24 hours. The reducing gas may contain hydrogen, carbon monoxide, etc., for example. By using the dehydrogenation catalyst subjected to the reduction treatment, the initial induction period of the dehydrogenation reaction can be shortened. The initial induction period means a state in which the supported metal in the dehydrogenation catalyst is reduced and is in an active state, and the activity of the catalyst is low.

  Next, the dehydrogenation process in this embodiment will be described in detail.

  The dehydrogenation step is a step in which a raw material gas is brought into contact with a dehydrogenation catalyst to perform an alkane dehydrogenation reaction to obtain a product gas containing unsaturated hydrocarbons.

  The dehydrogenation step may be performed, for example, by using a reactor filled with a dehydrogenation catalyst and circulating a raw material gas through the reactor. As the reactor, various reactors used for a gas phase reaction with a solid catalyst can be used. Examples of the reactor include a fixed bed reactor, a radial flow reactor, and a tubular reactor.

  The reaction type of the dehydrogenation reaction may be, for example, a fixed bed type, a moving bed type, or a fluidized bed type. Among these, the fixed bed type is preferable from the viewpoint of equipment cost.

  The reaction temperature of the dehydrogenation reaction, that is, the temperature in the reactor, may be 300 to 800 ° C. or 500 to 700 ° C. from the viewpoint of reaction efficiency. If reaction temperature is 500 degreeC or more, there exists a tendency for the production amount of unsaturated hydrocarbon to increase further. If reaction temperature is 700 degrees C or less, there exists a tendency for high activity to be maintained over a long period of time.

  The reaction pressure, that is, the atmospheric pressure in the reactor may be 0.01 to 1 MPa, may be 0.05 to 0.8 MPa, and may be 0.1 to 0.5 MPa. When the reaction pressure is in the above range, the dehydrogenation reaction is more likely to proceed, and a further excellent reaction efficiency tends to be obtained.

When the dehydrogenation step is performed in a continuous reaction mode in which the raw material gas is continuously supplied, the weight space velocity (hereinafter referred to as “WHSV”) may be 0.1 h ⁻¹ or more, and 1.0 h. it may also be ^-1 or more, may be at 100h ^-1 or less, may be ^{30h -1} or less. Here, WHSV is the ratio (supply rate / catalyst mass) of the feed rate (supply rate / time) of the raw material gas to the catalyst mass in a continuous reaction apparatus. In addition, the usage amount of the raw material gas and the catalyst may be appropriately selected in a more preferable range according to the reaction conditions, the activity of the catalyst, etc., and WHSV is not limited to the above range.

  In the dehydrogenation step, the reactor may be further charged with a catalyst other than the dehydrogenation catalyst (hereinafter also referred to as the first dehydrogenation catalyst).

  For example, in the present embodiment, a second dehydrogenation catalyst that catalyzes a dehydrogenation reaction from an olefin to a conjugated diene may be further charged after the first dehydrogenation catalyst of the reactor. Since the first dehydrogenation catalyst is excellent in the reaction activity of the dehydrogenation reaction from the alkane to the olefin, the second dehydrogenation catalyst is filled in the subsequent stage of the first dehydrogenation catalyst. The proportion of conjugated dienes can be increased.

  In addition, the production method according to the present embodiment includes contacting the product gas containing the olefin obtained in the dehydrogenation step (hereinafter also referred to as the first product gas) with the second dehydrogenation catalyst to dehydrate the olefin. A step of performing an elementary reaction to obtain a second product gas containing a conjugated diene (hereinafter also referred to as a second dehydrogenation step) may be further provided. According to such a production method, a product gas containing more conjugated diene can be obtained.

  As the second dehydrogenation catalyst, any olefin dehydrogenation catalyst can be used without particular limitation. For example, as the second dehydrogenation catalyst, a noble metal catalyst, a catalyst containing Fe and K, a catalyst containing Mo and the like can be used.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to an Example.

[Carrier Synthesis Example 1]
<Preparation of carrier A-1>
15 g of alumina classified to 0.5 to 1 mm (Neobead GB-13, manufactured by Mizusawa Chemical Co., Ltd., pH of a suspension suspended in water at a concentration of 1% by mass: 7.9), 18 A solution of .8 g Mg (NO ₃ ) ₂ .6H ₂ O dissolved in 56 mL water was added. The obtained mixed solution was stirred at 40 ° C. and 0.015 MPaA for 30 minutes using a rotary evaporator, and stirred at 40 ° C. and normal pressure for 30 minutes. Thereafter, water was removed under reduced pressure while stirring the mixture. The resulting solid was dried in an oven at 130 ° C. overnight. Next, the dried solid was calcined at 550 ° C. for 3 hours and at 800 ° C. for 3 hours under air flow. A solution obtained by dissolving 18.8 g of Mg (NO ₃ ) ₂ .6H ₂ O in 56 mL of water was added to the obtained solid again, and the same procedure was repeated to obtain carrier A-1.

  In the obtained carrier A-1, the Mg content was 17.4% by mass based on the total mass of the carrier. Further, in the carrier A-1, the total acid amount was 5.9 μmol / g.

[Catalyst Synthesis Example 1]
<Preparation of catalyst A-1>
An aqueous solution in which 79.6 mg of H ₂ PtCl ₆ .2H ₂ O was dissolved in 16 mL of water was added to 3.0 g of carrier A-1. The obtained mixed solution was stirred at 40 ° C. and 0.015 MPaA for 30 minutes using a rotary evaporator, and stirred at 40 ° C. and normal pressure for 30 minutes. Thereafter, water was removed under reduced pressure while stirring the mixture. The resulting solid was dried in an oven at 130 ° C. overnight. Next, the dried solid was calcined at 550 ° C. for 3 hours under air flow. A solution obtained by dissolving 0.311 g of SnCl ₂ .2H ₂ O in 20 mL of EtOH was added to the obtained solid. The resulting mixture was stirred at 40 ° C. and normal pressure for 1 hour using a rotary evaporator, and then EtOH was removed under reduced pressure. The resulting solid was dried in an oven at 130 ° C. overnight. Next, the dried solid was calcined at 550 ° C. for 3 hours under air flow. Further, hydrogen reduction was performed at 550 ° C. for 2 hours to obtain catalyst A-1.

[Carrier Synthesis Example 2]
<Preparation of carrier A-2>
37 g of alumina classified to 0.5 to 1 mm (Neobead GB-13, manufactured by Mizusawa Chemical Co., Ltd., pH: 7.9 of a suspension suspended in water at a concentration of 1% by mass), 37 A solution of .6 g Mg (NO ₃ ) ₂ .6H ₂ O dissolved in 56 mL water was added. The obtained mixed solution was stirred at 40 ° C. and 0.015 MPaA for 30 minutes using a rotary evaporator, and stirred at 40 ° C. and normal pressure for 30 minutes. Thereafter, water was removed under reduced pressure while stirring the mixture. The resulting solid was dried in an oven at 130 ° C. overnight. Next, the solid after drying was calcined at 550 ° C. for 3 hours and at 800 ° C. for 3 hours under air flow to obtain carrier A-2.

  In the obtained carrier A-2, the content of Mg was 17.2% by mass based on the total mass of the carrier. In carrier A-2, the total acid amount was 8.9 μmol / g.

[Catalyst synthesis example 2]
<Preparation of catalyst A-2>
A catalyst was prepared in the same manner as in Catalyst Synthesis Example 1 except that Support A-2 was used instead of Support A-1, and Catalyst A-2 was obtained.

[Carrier Synthesis Example 3]
<Preparation of carrier A-3>
105.5 g of Al (NO ₃ ) ₃ .9H ₂ O and 36.1 g of Mg (NO ₃ ) ₂ .6H ₂ O were added to 1 L of ion-exchanged water and vigorously stirred. While stirring the aqueous solution, a solution obtained by diluting concentrated aqueous ammonia twice was added dropwise at a rate of 0.1 mL / s until pH 10 was reached, stirred for 30 minutes, and then allowed to stand for 30 minutes. The precipitate was filtered and washed with 1.3 L of ion exchange water twice. Subsequently, the obtained precipitate was dried in an oven at 130 ° C. overnight. Finally, the solid after drying was calcined in three stages of 300 ° C. for 1 hour, 500 ° C. for 2 hours, and 800 ° C. for 4 hours under air flow to obtain carrier A-3.

  In the obtained carrier A-3, the content of Mg was 15.2% by mass based on the total mass of the carrier. Further, in the carrier A-3, the total acid amount was 10.6 μmol / g.

[Catalyst Synthesis Example 3]
<Preparation of catalyst A-3>
A catalyst was prepared in the same manner as in Catalyst Synthesis Example 1 except that Support A-3 was used instead of Support A-1, and Catalyst A-3 was obtained.

[Catalyst Synthesis Example 4]
<Preparation of catalyst A-4>
A catalyst was prepared in the same manner as in Catalyst Synthesis Example 1 except that alumina (Neobead GB-13, manufactured by Mizusawa Chemical Industry Co., Ltd.) classified to 0.5 to 1 mm was used as a carrier. Got. The total acid amount of alumina used as the carrier in Catalyst Synthesis Example 4 was 26.5 μmol / g.

Example 1
1.0 g of catalyst A-1 was charged into a tubular reactor, and the reaction tube was connected to a fixed bed flow reactor. Next, the upper layer of the reaction tube was heated to 550 ° C. while flowing a mixed gas of hydrogen and N ₂ (hydrogen: N ₂ = 5: 5 (mol ratio)) at 50 mL / min, and the temperature was increased to 550 ° C. for 1 hour. Retained. At the same time, the lower layer of the reaction tube was heated to 600 ° C. and held at that temperature for 1 hour. Subsequently, a mixed gas (raw material gas) of n-butane, N ₂ and water was supplied to the reactor, and n-butane in the raw material gas was dehydrogenated. Here, the molar ratio of n-butane, N ₂ and water in the raw material gas was adjusted to 1: 5: 3. The feed rate of the raw material gas to the tubular reactor was adjusted to 62 mL / min. The WHSV with respect to the total amount of the catalyst was adjusted to 1.0 h- ¹ . The pressure of the raw material gas in the tubular reactor was adjusted to atmospheric pressure.

  When 60 minutes passed from the start of the reaction, the product (product gas) of the dehydrogenation reaction was collected from the tubular reactor. Further, when 300 minutes passed from the reaction start time, the product (product gas) of the dehydrogenation reaction was collected from the tubular reactor. The reaction start time is the time when the supply of the source gas is started. The product gas collected at each time point was analyzed using a gas chromatograph (TCD-GC) equipped with a thermal conductivity detector. As a result of analysis, it was confirmed that the product gas contained butene and 1,3-butadiene. Based on the gas chromatograph, the butene concentration (unit: mass%) and the butadiene concentration (unit: mass%) in the product gas collected at each time point were quantified.

From the concentrations of butane, butene and 1,3-butadiene in the product gas, the butane conversion rate, butene yield and butadiene yield at the time of 60 minutes and at the time of 300 minutes were calculated. The butane conversion rate is defined by the following formula (1), the butadiene yield is defined by the following formula (2), and the butene yield is defined by the following formula (3).
R _Y1 = M _a / M ₀ × 100 (1)
R _Y2 = M _b / M ₀ × 100 (2)
R _Y3 = M _P / M ₀ × 100 (3)
R _Y1 in Formula (1) is a butane conversion, M ₀ is the number of moles of n- butane in the feed gas, M _a is the number of moles of n- butane in the product gas.
In Formula (2), R _Y1 is the butadiene yield, M ₀ is the number of moles of n-butane in the raw material gas, and M _b is the number of moles of 1,3-butadiene in the product gas.
_{R Y2} in Formula (3) is a butene yield, _{M 0} is the number of moles of n- butane in the feed gas, _{M P} is in the product gas of 1-butene, t-2-butene and c- The number of moles of 2-butene.

  As a result of the calculation, the butane conversion rate, butene yield and butadiene yield after 60 minutes were 64.7%, 51.2%, 9.8%, butane conversion rate and butene yield after 360 minutes, respectively. The rate and butadiene yield were 58.7%, 46.3%, and 9.6%, respectively.

(Example 2)
The dehydrogenation reaction of n-butane and the analysis of the product gas were performed in the same manner as in Example 1 except that the catalyst A-2 was used instead of the catalyst A-1. The butane conversion rate, butene yield and butadiene yield after 60 minutes from the start of the reaction were 66.9%, 53.4%, 8.8%, butane conversion rate and butene yield after 360 minutes, respectively. The rate and butadiene yield were 59.0%, 46.9%, and 9.0%, respectively.

(Example 3)
A dehydrogenation reaction of n-butane and analysis of the product gas were performed in the same manner as in Example 1 except that the catalyst A-3 was used instead of the catalyst A-1. The butane conversion rate, butene yield and butadiene yield after 60 minutes from the start of the reaction were 42.3%, 34.3%, 6.0%, butane conversion rate and butene yield after 360 minutes, respectively. The rate and butadiene yield were 35.2%, 27.9%, and 5.6%, respectively.

(Comparative Example 1)
A dehydrogenation reaction of n-butane and analysis of the product gas were performed in the same manner as in Example 1 except that the catalyst A-4 was used instead of the catalyst A-1. The butane conversion rate, butene yield and butadiene yield after 60 minutes from the start of the reaction were 35.5%, 29.6%, 3.8%, butane conversion rate and butene yield after 360 minutes, respectively. The rate and the butadiene yield were 14.4%, 10.3%, and 3.2%, respectively.

  The results of Examples 1 to 3 and Comparative Example 1 are shown in Table 1.

Claims (6)

Contacting a source gas containing an alkane with a dehydrogenation catalyst to obtain a product gas containing at least one unsaturated hydrocarbon selected from the group consisting of olefins and conjugated dienes,
The dehydrogenation catalyst is a catalyst in which a carrier containing Al and a Group 2 metal element is supported on a supported metal containing a Group 14 metal element and Pt,
The total acid amount measured by the ammonia TPD method of the carrier is 15 μmol / g or less,
A method for producing unsaturated hydrocarbons.   The manufacturing method of Claim 1 whose total acid amount measured by the ammonia TPD method of the said support | carrier is 10 micromol / g or less.   The manufacturing method according to claim 1 or 2, wherein the Group 14 metal element is Sn.   The manufacturing method as described in any one of Claims 1-3 whose said alkane is a C4-C10 alkane.   The production method according to any one of claims 1 to 4, wherein the alkane is butane, the olefin is butene, and the conjugated diene is butadiene. A first step of contacting a source gas containing an alkane with a first dehydrogenation catalyst to obtain a first product gas containing an olefin;
Contacting the first product gas with a second dehydrogenation catalyst to obtain a second product gas containing a conjugated diene;
With
The first dehydrogenation catalyst is a catalyst in which a carrier containing Al and a Group 2 metal element is supported on a supported metal containing a Group 14 metal element and Pt,
The total acid amount measured by the ammonia TPD method of the carrier is 15 μmol / g or less,
A process for producing conjugated dienes.