JP2016032784A - Oxidative dehydrogenation catalyst, production method therefor, and oxidative dehydrogenation process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oxidative dehydrogenation catalyst that exhibits excellent catalytic activity in an oxidative dehydrogenation reaction to obtain n-mono-olefin or i-mono-olefin such as butene or the like, and conjugated diene such as 1,3-butadiene or the like by oxidative dehydrogenation reacting a hydrocarbon raw-material comprising n-paraffin or i-paraffin such as butane or the like, or in an oxidative dehydrogenation reaction to obtain conjugated diene such as 1,3-butadiene or the like by oxidative dehydrogenation reacting a hydrocarbon raw-material comprising n-mono-olefin or i-mono-olefin such as butene or the like.SOLUTION: Provided is an oxidative dehydrogenation catalyst characterized in containing vanadium atom and magnesium atom and molybdenum atom and in which the ratio of the number of moles of molybdenum in terms of atom to the total number of moles of vanadium, magnesium and molybdenum in terms of atom, ((Mo/(V+Mg+Mo))×100), is 0.3 to 1.8 mol%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a catalyst for oxidative dehydrogenation, a method for producing the catalyst, and a method for oxidative dehydrogenation of hydrocarbons using the catalyst. Specifically, a hydrocarbon containing n-paraffin having 3 to 5 carbon atoms or n-monoolefin having 3 to 5 carbon atoms is oxidatively dehydrogenated in the presence of oxygen to produce the corresponding monoolefin or conjugated diene. The present invention relates to an oxidative dehydrogenation catalyst, a method for producing the catalyst, and a hydrocarbon oxidative dehydrogenation method using the catalyst.

  As a method for dehydrogenating lower hydrocarbons, a simple dehydrogenation process has been industrialized. However, this process is difficult to obtain a target product in a high yield due to equilibrium limitations, and requires a high temperature. Furthermore, there is a problem that deactivation due to coke deposition is large and catalyst regeneration needs to be performed frequently.

  On the other hand, attempts have been made to produce lower olefins or conjugated dienes from lower paraffins and lower olefins by an oxidative dehydrogenation method that has no constraints on equilibrium, and lower olefins or conjugated dienes from lower alkanes by oxidative dehydrogenation. Various catalysts have been proposed for producing the. For example, a nickel-niobium oxide catalyst (for example, Patent Document 1) as an ethylene production catalyst from ethane, a vanadium-magnesium oxide catalyst (for example, Patent Document 2) as a propylene production catalyst from propane, and n-butane As a butene and butadiene production catalyst, a molybdenum-magnesium oxide catalyst (for example, Patent Document 3) is known. However, these known catalysts have low oxidative dehydrogenation performance and low performance that cannot be used for industrialization.

Various methods for producing conjugated dienes from lower alkanes and lower olefins by dehydrogenation have also been studied. For example, as a method for producing 1,3-butadiene, a method for producing 1,3-butadiene by oxidative dehydrogenation from n-butane using a molybdenum-magnesium oxide catalyst or the like (for example, Patent Document 3), or chromia -A method of producing 1,3-butadiene by simple dehydrogenation of butane / butene using an alumina catalyst (for example, Non-Patent Document 1), Fe ₂ O ₃ -Cr ₂ O ₃ -K ₂ CO ₃ catalyst was used A method for producing 1,3-butadiene by simple dehydrogenation of butene (for example, Patent Document 4) has been studied. Among them, the method by simple dehydrogenation of butane / butene has been commercialized, but there is a problem that coke deactivation is large and catalyst regeneration needs to be frequently performed.

  In recent years, a method for producing butadiene by oxidative dehydrogenation of n-butene using a bismuth-molybdenum catalyst (for example, Patent Document 5) has been studied. However, although the bismuth-molybdenum catalyst has high reaction activity and 1,3-butadiene yield, there is a problem that adjustment on a commercial scale is difficult due to the complicated catalyst system.

US72227049B2 JP 2009-39679 A Japanese Patent Laid-Open No. 3-74335 Japanese Patent Laid-Open No. 56-21652 JP 2010-90082 A

G. F. Hornadey, Petroleum Engr. , 26, no. 11, C-7 (1954)

  Accordingly, an object of the present invention is to oxidize and dehydrogenate a hydrocarbon raw material containing n-paraffin or i-paraffin such as butane, so that n-monoolefin or i-monoolefin such as butene, 1,3-butadiene, etc. Oxidative dehydrogenation reaction to obtain a conjugated diene of 1,3-butadiene or the like by an oxidative dehydrogenation reaction to obtain a conjugated diene of the hydrocarbon raw material containing n-monoolefin or i-monoolefin such as butene It is an object of the present invention to provide an oxidative dehydrogenation catalyst exhibiting excellent catalytic activity.

  As a result of intensive studies to solve the above-described problems in the prior art, the present inventors have included vanadium, magnesium, and molybdenum as essential components, and the ratio of these metal components is a specific ratio. The inventors have found that the raw catalyst exhibits excellent catalytic activity in the oxidative dehydrogenation reaction in which paraffin and monoolefin are oxidatively dehydrogenated to obtain the corresponding monoolefin or conjugated diene, and the present invention has been completed.

That is, the present invention (1) is an oxidative dehydrogenation catalyst for performing oxidative dehydrogenation of paraffins having 3 to 5 carbon atoms or monoolefins having 3 to 5 carbon atoms contained in a hydrocarbon raw material,
The hydrocarbon raw material is a hydrocarbon raw material containing a paraffin having 3 to 5 carbon atoms, a hydrocarbon raw material containing a monoolefin having 3 to 5 carbon atoms, or a paraffin having 3 to 5 carbon atoms and a monoolefin having 3 to 5 carbon atoms, A hydrocarbon feedstock containing
The oxidative dehydrogenation catalyst contains a vanadium atom, a magnesium atom, and a molybdenum atom, and the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles in terms of atoms of vanadium, magnesium, and molybdenum ((Mo / (V + Mg + Mo)) × 100) is 0.3 to 1.8 mol%,
An oxidative dehydrogenation catalyst characterized by the above is provided.

The present invention (2) is an oxidative dehydrogenation catalyst for producing n-butene and 1,3-butadiene from n-butane contained in a hydrocarbon raw material by an oxidative dehydrogenation reaction,
The oxidative dehydrogenation catalyst contains a vanadium atom, a magnesium atom, and a molybdenum atom, and the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles in terms of atoms of vanadium, magnesium, and molybdenum ((Mo / (V + Mg + Mo)) × 100) is 0.3 to 1.8 mol%,
An oxidative dehydrogenation catalyst characterized by the above is provided.

  In the present invention (3), a raw material mixture in which a vanadium source, a magnesium source and a molybdenum source are dissolved or dispersed in water is prepared, and then water in the raw material mixture is evaporated and removed. The present invention provides a method for producing an oxidative dehydrogenation catalyst, comprising obtaining a raw material mixture powder and then firing the raw material mixture powder.

  Moreover, this invention (4) is C3-C5 paraffin or C3-C5 contained in a hydrocarbon raw material at 400-700 degreeC in presence of the oxidative dehydrogenation catalyst of this invention (1). It is an oxidative dehydrogenation reaction for oxidative dehydrogenation of monoolefin, and the hydrocarbon raw material is a hydrocarbon raw material containing paraffins having 3 to 5 carbon atoms, a hydrocarbon raw material containing monoolefins having 3 to 5 carbon atoms, or the number of carbon atoms The present invention provides a oxidative dehydrogenation method characterized by being a hydrocarbon raw material containing 3 to 5 paraffins and 3 to 5 carbon monoolefins.

  According to the present invention, by oxidative dehydrogenation of a hydrocarbon raw material containing n-paraffin or i-paraffin such as butane, an n-monoolefin or i-monoolefin such as butene, or a conjugate such as 1,3-butadiene. In an oxidative dehydrogenation reaction for obtaining a conjugated diene such as 1,3-butadiene by an oxidative dehydrogenation reaction for obtaining a diene or an oxidative dehydrogenation reaction of a hydrocarbon raw material containing an n-monoolefin or i-monoolefin such as butene. An oxidative dehydrogenation catalyst exhibiting excellent catalytic activity can be provided.

3 is an XRD chart of catalyst A. 4 is an XRD chart of catalyst B. 3 is an XRD chart of catalyst C. 3 is an XRD chart of catalyst D. 3 is an XRD chart of catalyst E.

The oxidative dehydrogenation catalyst of the present invention is an oxidative dehydrogenation catalyst for performing oxidative dehydrogenation of paraffins having 3 to 5 carbon atoms or monoolefins having 3 to 5 carbon atoms contained in a hydrocarbon raw material,
The hydrocarbon raw material is a hydrocarbon raw material containing a paraffin having 3 to 5 carbon atoms, a hydrocarbon raw material containing a monoolefin having 3 to 5 carbon atoms, or a paraffin having 3 to 5 carbon atoms and a monoolefin having 3 to 5 carbon atoms, A hydrocarbon feedstock containing
The oxidative dehydrogenation catalyst contains a vanadium atom, a magnesium atom, and a molybdenum atom, and the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles in terms of atoms of vanadium, magnesium, and molybdenum ((Mo / (V + Mg + Mo)) × 100) is 0.3 to 1.8 mol%,
Is an oxidative dehydrogenation catalyst.

  The oxidative dehydrogenation catalyst of the present invention is a catalyst for oxidative dehydrogenation that oxidatively dehydrogenates paraffins having 3 to 5 carbon atoms or monoolefins having 3 to 5 carbon atoms. The hydrocarbon raw material contains paraffins having 3 to 5 carbon atoms and does not contain monoolefins having 3 to 5 carbon atoms, those containing monoolefins having 3 to 5 carbon atoms and no paraffins having 3 to 5 carbon atoms, Some contain both paraffins having 3 to 5 carbon atoms and monoolefins having 3 to 5 carbon atoms. Examples of the n-paraffin having 3 to 5 carbon atoms contained in the hydrocarbon raw material include propane, n-butane and n-pentane. Examples of the i-paraffin having 3 to 5 carbon atoms include i-butane and i-pentane. Examples of the n-monoolefin having 3 to 5 carbon atoms include n-butene and n-pentene, and examples of the i-monoolefin having 3 to 5 carbon atoms include i-pentene. As paraffin, n-butane is preferable, and as monoolefin, n-butene is preferable. In particular, the oxidative dehydrogenation catalyst of the present invention is advantageously used in an oxidative dehydrogenation reaction in which n-butane is oxidatively dehydrogenated to obtain n-butene and 1,3-butadiene.

  The hydrocarbon raw material may contain hydrocarbons other than paraffins having 3 to 5 carbon atoms and monoolefins having 3 to 5 carbon atoms. The content of the paraffin having 3 to 5 carbon atoms and the monoolefin having 3 to 5 carbon atoms in the hydrocarbon raw material is not particularly limited, but is 85% by mass or more, preferably 90% by mass or more, particularly preferably 95% by mass or more. It is. The content of paraffin having 3 to 5 carbon atoms and monoolefin having 3 to 5 carbon atoms in the hydrocarbon raw material means that the hydrocarbon raw material contains paraffin having 3 to 5 carbon atoms and monoolefin having 3 to 5 carbon atoms. Is included, it indicates the total content of paraffins having 3 to 5 carbon atoms, and when the hydrocarbon raw material contains monoolefins having 3 to 5 carbon atoms and no paraffins having 3 to 5 carbon atoms, 3 carbon atoms are contained. Refers to the total content of ˜5 monoolefins, and when the hydrocarbon raw material contains both paraffins having 3 to 5 carbon atoms and monoolefins having 3 to 5 carbon atoms, paraffins having 3 to 5 carbon atoms and 3 carbon atoms Refers to the total content of ˜5 monoolefins.

  Using the oxidative dehydrogenation catalyst of the present invention, oxidative dehydrogenation of an n-paraffin having 3 to 5 carbon atoms or an n-monoolefin having 3 to 5 carbon atoms is performed to produce the corresponding n-monoolefin or conjugated diene. In this case, the content of the n-paraffin having 3 to 5 carbon atoms and the n-monoolefin having 3 to 5 carbon atoms in the hydrocarbon raw material is 30% by mass or more, preferably 40% by mass or more, particularly preferably 50% by mass. That's it. In this case, the hydrocarbon raw material may contain hydrocarbons other than n-paraffins having 3 to 5 carbon atoms and n-monoolefins having 3 to 5 carbon atoms. The content of the n-paraffin having 3 to 5 carbon atoms and the n-monoolefin having 3 to 5 carbon atoms in the hydrocarbon raw material means that the hydrocarbon raw material contains n-paraffin having 3 to 5 carbon atoms. When 3-5 n-monoolefins are not included, the total content of n-paraffins having 3 to 5 carbon atoms is indicated, and the hydrocarbon raw material contains 3 to 5 carbon atoms n-monoolefins and 3 to 3 carbon atoms. When it does not contain 5 n-paraffins, it refers to the total content of n-monoolefins having 3 to 5 carbon atoms, and hydrocarbon raw materials are n-paraffins having 3 to 5 carbon atoms and n-paraffins having 3 to 5 carbon atoms. When both monoolefins are included, the total content of n-paraffins having 3 to 5 carbon atoms and n-monoolefins having 3 to 5 carbon atoms is indicated.

  The oxidative dehydrogenation catalyst of the present invention is suitably used as a catalyst for an oxidative dehydrogenation reaction in which paraffin or monoolefin is oxidatively dehydrogenated to obtain a conjugated diene. When the conjugated diene to be produced is 1,3-butadiene, the raw material for 1,3-butadiene is n-butane or n-butene. In this case, the n-butane and n-butene in the hydrocarbon raw material Content is 30 mass% or more, Preferably it is 40 mass% or more, Most preferably, it is 50 mass% or more. The contents of n-butane and n-butene in the hydrocarbon raw material refer to the content of n-butane when the hydrocarbon raw material contains n-butane and does not contain n-butene. Refers to the content of n-butene when it contains n-butene and does not contain n-butane, and when the hydrocarbon feed contains both n-butane and n-butene, Refers to the total content. When the conjugated diene to be produced is isoprene, the raw material for isoprene is i-pentane or i-pentene. In this case, the content of i-pentane and i-pentene in the hydrocarbon raw material is 30% by mass. % Or more, preferably 40% by mass or more, particularly preferably 50% by mass or more. The content of i-pentane and i-pentene in the hydrocarbon raw material refers to the content of i-pentane when the hydrocarbon raw material contains i-pentane and does not contain i-pentene. Refers to the content of i-pentene when i-pentene is included but does not include i-pentane, and when the hydrocarbon feedstock includes both i-pentane and i-pentene, Refers to the total content.

  Although it does not restrict | limit especially as a hydrocarbon raw material, For example, in a petroleum refining process, C3 mixture obtained by atmospheric distillation, C4 mixture, C5 mixture, C3 mixture produced by fluid catalytic cracking, C4 mixture, and reforming reaction Examples thereof include C3 mixture, C4 mixture, C5 mixture, C4 mixture produced by naphtha decomposition in a petrochemical process, C4 raffinate remaining after separation of conjugated diene from C5 mixture by extraction or the like, C5 raffinate, and the like. Moreover, the recovered liquid after taking out the target component from the reaction product obtained by performing the oxidative dehydrogenation of the hydrocarbon raw material using the oxidative dehydrogenation catalyst of the present invention is also exemplified as the hydrocarbon raw material. Further, even if the hydrocarbon raw material is directly subjected to an oxidative dehydrogenation reaction, propane, n-butane, n-butene, i-pentane, and i-pentene are separated from these hydrocarbon raw materials in advance and subjected to an oxidative dehydrogenation reaction. May be provided.

  The oxidative dehydrogenation catalyst of the present invention contains vanadium atoms, magnesium atoms, and molybdenum atoms. In the oxidative dehydrogenation catalyst of the present invention, the selectivity of n-olefins such as butene or conjugated dienes such as butadiene is enhanced by the coexistence of vanadium, magnesium and molybdenum.

In the oxidative dehydrogenation catalyst of the present invention, the ratio (mol / (V + Mg + Mo)) × 100 of the number of moles of molybdenum in terms of the total number of moles of vanadium, magnesium and molybdenum in terms of atoms is 0.3 to 1. It is 8 mol%, preferably 0.5 to 1.6 mol%, particularly preferably 0.6 to 1.2 mol%. The ratio of the number of moles in terms of atoms of molybdenum to the total number of moles in terms of atoms of vanadium, magnesium and molybdenum in the oxidative dehydrogenation catalyst of the present invention is within the above range, whereby the selectivity of monoolefin or conjugated diene and The yield is high. On the other hand, in the oxidative dehydrogenation catalyst of the present invention, if the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles of atoms in vanadium, magnesium and molybdenum is less than the above range, the combustion reaction is not suppressed, and CO or generation of CO ₂ is increased, also exceeds the above range, the decomposition reaction proceeds, become much degradation products.

  In the oxidative dehydrogenation catalyst of the present invention, the ratio of the number of moles of molybdenum converted to the number of moles converted to atoms of magnesium ((Mo / Mg) × 100) is preferably 0.2 to 8.0 mole%. Preferably it is 0.3-2.2 mol%, More preferably, it is 0.7-2.0 mol%, Most preferably, it is 1.0-1.5 mol%. When the ratio of the number of moles of molybdenum converted to the number of moles converted to atoms of magnesium in the oxidative dehydrogenation catalyst of the present invention is within the above range, the selectivity and yield of the monoolefin or conjugated diene increases. .

  In the oxidative dehydrogenation catalyst of the present invention, the ratio of the number of moles of molybdenum converted to the number of moles of vanadium converted to atoms ((Mo / V) × 100) is preferably 1.0 to 12.0 mol%, particularly Preferably it is 2.0-10.0 mol%, More preferably, it is 4.0-8.0 mol%. When the ratio of the number of moles of molybdenum converted to the number of moles of vanadium in the oxidative dehydrogenation catalyst of the present invention is within the above range, the selectivity and yield of the monoolefin or conjugated diene increase. .

  In the oxidative dehydrogenation catalyst of the present invention, the ratio of the total number of moles of vanadium and magnesium in terms of atoms to the total number of moles of vanadium, magnesium and molybdenum in terms of atoms (((V + Mg) / (V + Mg + Mo)) × 100) is preferable. Is 98.2 to 99.7 mol%, particularly preferably 98.4 to 99.5 mol%, more preferably 98.8 to 99.4 mol%. When the ratio of the total number of moles of vanadium and magnesium in terms of atoms to the total number of moles of vanadium, magnesium and molybdenum in the oxidative dehydrogenation catalyst of the present invention is within the above range, the monoolefin or conjugated diene Selectivity and yield are increased.

  In the oxidative dehydrogenation catalyst of the present invention, the ratio of the number of moles of vanadium in terms of atoms to the number of moles of atoms in magnesium ((V / Mg) × 100) is preferably 2.0 to 30.0 mol%, particularly Preferably it is 5.0-25.0 mol%, More preferably, it is 10.0-20.0 mol%. When the ratio of the number of moles of vanadium in terms of atoms to the number of moles of atoms in magnesium in the oxidative dehydrogenation catalyst of the present invention is within the above range, the selectivity and yield of the monoolefin or conjugated diene are increased. .

  In the oxidative dehydrogenation catalyst of the present invention, the vanadium atom, the magnesium atom and the molybdenum atom are in the state of a single metal oxide, or in the state of a composite oxide composed of these two metals, or in a single state. It exists in both metal oxide and composite oxide states. That is, in the oxidative dehydrogenation catalyst of the present invention, the state or structure in which each metal atom forms the metal oxide is not particularly limited. For example, (i) a composite oxidation of vanadium, magnesium and molybdenum Or (iii) a composite oxide of vanadium, magnesium and molybdenum supported on a magnesium oxide, or (iii) a molybdenum oxide on a composite oxide of vanadium and magnesium. Even if it is supported (iv) (v) (i) to (iv) (v) (v) (i) to (iv) even if the oxide of magnesium is supported by a composite oxide of vanadium and magnesium and an oxide of molybdenum It may be a mixture of

Magnesium vanadate is a complex oxide, and there exist ortho-forms (Mg ₃ V ₂ O ₈ ), pyro-forms, and meta-forms. The oxidative dehydrogenation catalyst of the present invention preferably contains an oxide of magnesium, a magnesium vanadate composite oxide, and an oxide of molybdenum, and an oxide of magnesium, an ortho vanadate magnesium composite oxide, and an oxide of molybdenum It is particularly preferable to contain In the above (i) to (v), the composite oxide of vanadium and magnesium is preferably a magnesium orthovanadate composite oxide.

In the X-ray diffraction analysis, the oxidative dehydrogenation catalyst of the present invention has a diffraction peak of 2θ = 23.0 to 23.2 ° with respect to the intensity (a) of the peak top of the diffraction peak of 2θ = 42.9 to 43.1 °. The relative intensity ratio (x / a) of the peak top intensity (x) is 0.1 or less, preferably 0.08 or less, particularly preferably 0.04 or less. A diffraction peak (a) having 2θ of 42.9 to 43.1 ° in X-ray diffraction analysis is a diffraction peak derived from the (200) plane of MgO, and 2θ in X-ray diffraction analysis is 23.0 to 23.0. The diffraction peak (x) at 23.2 ° is a diffraction peak derived from the (0-12) plane of MgMoO ₄ . The relative intensity ratio (x / a) is a peak height ratio of diffraction peaks.

In the production of a metal oxide containing vanadium, magnesium and molybdenum as metal components, first, a magnesium vanadate composite oxide is produced, and the obtained magnesium vanadate composite oxide is impregnated with a molybdenum compound solution. Then, when a metal oxide containing vanadium, magnesium and molybdenum as metal components is produced by firing the magnesium vanadate complex oxide impregnated with the molybdenum compound solution (hereinafter referred to as “magnesium vanadate complex oxide”). In addition, the X-ray diffraction analysis chart of the obtained metal oxide shows 2θ = 19.34 ° ((110) plane), 23.05 ° ((0-12). ) plane), near 26.45 ° ((1-21) plane), See This diffraction peaks derived from MgMoO ₄ It is. On the other hand, when a metal oxide is produced by the method for producing an oxidative dehydrogenation catalyst of the present invention described below, the X-ray diffraction chart of the obtained metal oxide shows 2θ = 19.34 °, 23.05. No diffraction peak is observed at around °, 26.45 °, or even if diffraction peaks are observed at around 2θ = 19.34 °, 23.05 °, 26.45 °. . That is, the metal oxide (oxidation dehydrogenation catalyst) obtained by the method for producing an oxidative dehydrogenation catalyst of the present invention is different from the metal oxide obtained by the Mo supporting method by impregnation into the magnesium vanadate composite oxide. The structure is different.

In the present invention, the measurement conditions for X-ray diffraction analysis (XRD) are as follows. The relative intensity ratio (x / a) is a peak height ratio of diffraction peaks.
<Measurement conditions>
Radiation source: CuKα
Tube voltage: 40 kV
Tube current: 40 mA
Sampling width: 0.02 °
Scanning speed: 2 ° / min

  The oxidative dehydrogenation catalyst of the present invention is a compound mainly composed of vanadium atoms, magnesium atoms, molybdenum atoms and oxygen atoms, but the oxidative dehydrogenation catalyst of the present invention does not impair the effects of the present invention. It may contain other metal atoms in the range. In addition, the oxidative dehydrogenation catalyst of the present invention is allowed to contain impurities other than the metal atoms as long as the effects of the present invention are not impaired.

  The oxidative dehydrogenation catalyst of the present invention is a powdered or granular metal oxide, but such a powdery or granular oxidative dehydrogenation catalyst of the present invention may be used in a powdered or granular form, Alternatively, the powdered or granular oxidative dehydrogenation catalyst of the present invention may be molded by compression molding or the like and used as a molded body, or the powdered or granular oxidative dehydrogenation catalyst of the present invention may be used as a binder. May be used as a molded body.

When the oxidative dehydrogenation catalyst of the present invention is used as a molded body molded using a binder, the amount of vanadium converted to V ₂ O _{5, the} amount of magnesium converted to MgO and the amount of molybdenum converted to MoO _{3 with} respect to the mass of the entire molded body The total ratio of (((V ₂ O ₅ converted amount + MgO converted amount + MoO ₃ converted amount) / total mass of molded article) × 100) is preferably 50% by mass or more, particularly preferably 70% by mass or more. The ratio of the total amount of vanadium in terms of V ₂ O _{5, the} amount of magnesium in terms of MgO and the amount of molybdenum in terms of MoO ₃ relative to the total mass of the compact is within the above range, so that the selectivity and yield of monoolefin or conjugated diene Becomes higher. In the present invention, the terms _of V ₂ O ₅ amount of vanadium, vanadium atom contained in the molded body, the mass of V ₂ O ₅ when calculated as being present as all V ₂ O ₅ In addition, the MgO equivalent amount of magnesium refers to the mass of MgO when it is calculated that all the magnesium atoms contained in the compact are present as MgO, and is equivalent to MoO _{3 of} molybdenum. the amount and the molybdenum atom contained in the molded body, refers to the mass of MoO ₃ when calculated as being present all as MoO _3.

  When the oxidative dehydrogenation catalyst of the present invention is used as a molded body molded using a binder, the total number of moles of vanadium, magnesium and molybdenum in terms of atoms relative to the total number of moles of atoms in all metal atoms in the shaped body. The ratio (((V + Mg + Mo) / total metal atoms in the molded body) × 100) is preferably 60 mol% or more, particularly preferably 80 mol% or more. When the ratio of the total number of moles of vanadium, magnesium and molybdenum in terms of atoms to the total number of moles of atoms of all metal atoms in the compact is in the above range, the selectivity and yield of monoolefin or conjugated diene are high. Become.

  The oxidative dehydrogenation catalyst of the present invention is preferably produced by the method for producing the oxidative dehydrogenation catalyst of the present invention described below.

  The method for producing an oxidative dehydrogenation catalyst of the present invention comprises preparing a raw material mixed solution in which a vanadium source, a magnesium source, and a molybdenum source are dissolved or dispersed in water, and then in the obtained raw material mixed solution. It is a method for producing an oxidative dehydrogenation catalyst, characterized by evaporating and removing water to obtain a raw material mixture powder and then firing the obtained raw material mixture powder.

  In the method for producing an oxidative dehydrogenation catalyst of the present invention, first, a raw material mixed solution in which a vanadium source, a magnesium source, and a molybdenum source are dissolved or dispersed in water is prepared.

  A vanadium source, a magnesium source, and a molybdenum source are a metal atom source used as the supply source of the metal atom which comprises an oxidative dehydrogenation catalyst, and is a compound containing vanadium, magnesium, and molybdenum. Examples of such metal atom sources include vanadium, magnesium, molybdenum chlorides, nitrates, sulfates, acetates, ammonium salts, and complex salts composed of two or more of these metal atoms. .

  The method of preparing the raw material mixture is not particularly limited, and each metal atom source may be directly added to water and mixed with stirring, or a solution obtained by dissolving or dispersing a metal atom source in water. And may be mixed with stirring. In preparation of the raw material mixture, stirring and mixing are performed while heating at 40 to 60 ° C., if necessary.

  Content of each metal atom in a raw material liquid mixture is suitably selected by the molar ratio of each metal atom which comprises the oxidative dehydrogenation catalyst made into a manufacturing objective.

  In the method for producing an oxidative dehydrogenation catalyst of the present invention, the water in the obtained raw material mixture is then evaporated to remove the water to obtain a raw material mixture powder. The method for evaporating water in the raw material mixture is not particularly limited, and examples thereof include a method of heating the raw material mixture under normal pressure or reduced pressure. When evaporation of water in the raw material mixture is performed under normal pressure, the heating temperature is not particularly limited, but is preferably 50 to 150 ° C. When the water in the raw material mixture is evaporated under reduced pressure, the heating temperature is appropriately selected according to the degree of reduced pressure. Moreover, after performing the evaporation operation of water, it can dry as needed. Although the drying temperature in the case of drying is not restrict | limited in particular, Preferably it is 60-150 degreeC, and drying time should just be about 6 to 48 hours.

  In the method for producing an oxidative dehydrogenation catalyst of the present invention, the obtained raw material mixture powder is then fired to obtain an oxidative dehydrogenation catalyst. The firing temperature is not particularly limited, but is preferably 400 to 900 ° C, particularly preferably 500 to 800 ° C. The firing time is not particularly limited, but is preferably 3 to 30 hours. In firing the raw material mixture powder, the fired product may be fired a plurality of times by firing the fired product at the same temperature or at different temperatures. However, in consideration of the influence of sintering of the catalyst due to calcination at high temperature, the maximum temperature of calcination is preferably 750 ° C. or less.

  In firing the raw material mixture powder, it is preferable that the firing target is sufficiently ground during firing to prevent the catalyst components from becoming uneven during firing. For grinding, a mortar, a ball mill, or the like is used, and either a manual type or an automatic type can be used.

  The oxidative dehydrogenation method of the present invention comprises a C3-5 paraffin or a C3-5 monoolefin contained in a hydrocarbon raw material at 400 to 700 ° C. in the presence of the oxidative dehydrogenation catalyst of the present invention. It is an oxidative dehydrogenation reaction in which oxidative dehydrogenation is performed, and the hydrocarbon raw material includes a hydrocarbon raw material containing paraffin having 3 to 5 carbon atoms, a hydrocarbon raw material containing monoolefin having 3 to 5 carbon atoms, or 3 to 5 carbon atoms. It is an oxidative dehydrogenation method characterized by being a hydrocarbon raw material containing paraffin and 3 to 5 carbon monoolefin. That is, the oxidative dehydrogenation method of the present invention uses a hydrocarbon raw material containing a paraffin having 3 to 5 carbon atoms or a monoolefin having 3 to 5 carbon atoms as a raw material, and uses the oxidative dehydrogenation catalyst of the present invention as a catalyst. The oxidative dehydrogenation reaction is performed.

  The hydrocarbon raw material according to the oxidative dehydrogenation method of the present invention is the same as the hydrocarbon raw material according to the oxidative dehydrogenation catalyst of the present invention.

The reaction temperature of the oxidative dehydrogenation reaction in the oxidative dehydrogenation method of the present invention is 400 to 700 ° C, preferably 500 to 700 ° C, particularly preferably 600 to 675 ° C. When the reaction temperature of the oxidative dehydrogenation is in the above range, the production of CO or CO _{2 and} the production of coke are small, and the selectivity and yield of monoolefin or conjugated diene are increased. On the other hand, when the reaction temperature of the oxidative dehydrogenation reaction is less than the above range, the conversion rate or the yield of monoolefin or conjugated diene becomes low. When the reaction temperature exceeds the above range, the decomposition reaction proceeds excessively, and CO or CO ₂ generation and coke generation increase.

As an example of the oxidative dehydrogenation method of the present invention, for example, a method of supplying a raw material gas under heating to a reaction apparatus using a fixed bed flow type reaction apparatus filled with a catalyst can be mentioned. The source gas is supplied, for example, as a mixed gas of paraffin, olefin, or a hydrocarbon containing paraffin or olefin, an oxygen source, and a diluent. Pure oxygen or air is used as the oxygen source. Nitrogen, helium, or steam is used as the dilution gas, but steam is preferably used in order to suppress the heat generated by the reaction between the source gas and the oxygen source. The supply amount of the raw material gas is not particularly limited, and is appropriately adjusted depending on catalyst activity, catalyst filling amount, contact time, pressure loss, and the like. When paraffin, olefin, or a mixed gas of hydrocarbon and oxygen containing paraffin or olefin is used as a raw material gas, oxygen excess increases the amount of CO ₂ produced by complete oxidation of paraffin or olefin. The partial pressure ratio of paraffin or olefin to paraffin (paraffin or olefin / oxygen) is preferably 0.5 or more. The reaction pressure is not particularly limited, and may be normal pressure or increased pressure.

  The oxidative dehydrogenation catalyst of the present invention is an oxidative dehydrogenation catalyst obtained by the method for producing an oxidative dehydrogenation catalyst of the present invention. That is, the oxidative dehydrogenation catalyst of the present invention prepares a raw material mixture in which a vanadium source, a magnesium source, and a molybdenum source are dissolved or dispersed in water, and then the water in the obtained raw material mixture Is an oxidative dehydrogenation catalyst obtained by evaporating and removing a raw material mixture powder and then firing the obtained raw material mixture powder.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Example 1
<Catalyst A> 0.5 Mo-Mg-V-O catalyst Into 200 ml of distilled water, 3.340 g of ammonium vanadate is dissolved. Further, 8.767 g of magnesium hydroxide and 4.3 ml of distilled water are mixed with ammonium molybdate tetrahydrate. An aqueous solution in which 0.151 g of the Japanese product was dissolved was added and stirred to obtain a raw material mixture.
Next, the obtained raw material mixture was heated to 50 ° C. with stirring to evaporate to dryness, and then the evaporated dry matter was dried at 110 ° C. for 12 hours to obtain a raw material mixture powder.
Next, the obtained raw material mixture powder was calcined in the air at 700 ° C. for 6 hours to obtain Catalyst A.
Subsequently, X-ray diffraction analysis of the obtained catalyst A was performed. As a result, the catalyst A showed a crystal structure of magnesium orthovanadate and magnesium oxide. The obtained XRD chart is shown in FIG. Further, the relative intensity ratio (x / a) was determined from the XRD chart. The results are shown in Table 1.

(Example 2)
<Catalyst B> 1.1 Mo-Mg-V-O catalyst A catalyst was produced in the same manner as in Example 1 except that an aqueous solution in which 0.353 g of ammonium molybdate tetrahydrate was dissolved in 10 ml of distilled water was used. Catalyst B was obtained.
Subsequently, the obtained catalyst B was subjected to X-ray diffraction analysis. As a result, Catalyst B showed a crystal structure of magnesium orthovanadate and magnesium oxide. Moreover, the obtained XRD chart is shown in FIG. Further, the relative intensity ratio (x / a) was determined from the XRD chart. The results are shown in Table 1.

(Example 3)
<Catalyst C> 1.6Mo—Mg—V—O catalyst Production of catalyst in the same manner as in Example 1 except that 0.504 g of ammonium molybdate tetrahydrate was dissolved in 14.3 ml of distilled water. The catalyst C was obtained.
Subsequently, the obtained catalyst C was subjected to X-ray diffraction analysis. As a result, catalyst C showed a crystal structure of magnesium orthovanadate and magnesium oxide. The obtained XRD chart is shown in FIG. Further, the relative intensity ratio (x / a) was determined from the XRD chart. The results are shown in Table 1.

(Comparative Example 1)
<Catalyst D> 2.0 Mo-Mg-V-O catalyst A catalyst was produced in the same manner as in Example 1 except that an aqueous solution in which 0.706 g of ammonium molybdate tetrahydrate was dissolved in 20 ml of distilled water was used. Catalyst D was obtained.
Subsequently, X-ray diffraction analysis of the obtained catalyst D was performed. As a result, catalyst D showed a crystal structure of magnesium orthovanadate and magnesium oxide. Moreover, the obtained XRD chart is shown in FIG. Further, the relative intensity ratio (x / a) was determined from the XRD chart. The results are shown in Table 1.

(Comparative Example 2)
<Catalyst E> Mg-V-O catalyst 3.340 g of ammonium vanadate was dissolved in 200 ml of distilled water, and further 8.767 g of magnesium hydroxide was added and stirred to obtain a raw material mixture.
Next, the obtained raw material mixture was heated to 50 ° C. with stirring to evaporate to dryness, and then the evaporated dry matter was dried at 110 ° C. for 12 hours to obtain a raw material mixture powder.
Next, the obtained raw material mixture powder was calcined in the air at 700 ° C. for 6 hours to obtain Catalyst E.
Subsequently, the obtained catalyst E was subjected to X-ray diffraction analysis. As a result, catalyst E showed a crystal structure of magnesium orthovanadate and magnesium oxide. Moreover, the obtained XRD chart is shown in FIG. Further, the relative intensity ratio (x / a) was determined from the XRD chart. The results are shown in Table 1.

(X-ray diffraction analysis)
Powder X-ray diffraction analysis of the obtained catalyst was performed under the following measurement conditions using Ultima IV (manufactured by Regaku).
<Measurement conditions>
Radiation source: CuKα
Tube voltage: 40 kV
Tube current: 40 mA
Sampling width: 0.02 °
Scanning speed: 2 ° / min Scanning angle: 5-90 °

  The relative intensity ratio of the diffraction peak (x) of 2θ = 23.0 to 23.2 ° to the diffraction peak (a) of 2θ = 42.9 to 43.1 ° in the obtained X-ray diffraction chart (x / a ) (Peak height ratio of diffraction peaks) was obtained respectively.

(Evaluation of catalyst performance)
Using an atmospheric pressure fixed bed flow type reactor, the oxidative dehydrogenation reaction was performed as follows, and the performance of the catalyst was evaluated.
The reaction apparatus was charged with 0.25 g of the catalyst obtained as described above. Next, the temperature inside the reaction tube was raised to 450 ° C. while allowing air to flow through the reaction apparatus at 31.5 ml / min. After reaching 450 ° C., 31.5 ml / min of air was added and the mixture was circulated for 30 minutes to pretreat the catalyst (oxidation treatment). After completion of the pretreatment, steam was added at 112 ml / min and n-butane was added at 3.1 ml / min to circulate, so that n-butane: air: steam (molar ratio) = 1: 10: 36 and the total flow rate was 146. The raw material gas was circulated so that it might become 6 ml / min, and the oxidative dehydrogenation reaction of n-butane was performed for 60 minutes. The reaction results are shown in Tables 2-6.

n- butane conversion, CO, CO _2, hydrocarbons having 1 to 3 carbon atoms, butene and butadiene selectivity, butene and butadiene yield, was calculated as follows.

  Conversion rate (%) = ((number of moles of n-butane carbon in raw material gas−number of carbon moles of n-butane in product gas) / number of moles of n-butane carbon in raw material gas) × 100

Product selectivity (%) = (number of moles of carbon in each product gas / (number of moles of n-butane carbon in raw material gas−number of moles of n-butane carbon in product gas)) × 100
* In the formula, the number of carbon moles of each product is the number of carbon moles of CO, CO ₂ , butene, and butadiene, which are the targets of selectivity.

  Butene yield (%) = (number of moles of butene carbon in the product gas / total number of moles of carbon in the product gas) × 100

  Butadiene yield (%) = (number of moles of butadiene in product gas / total number of moles of carbon in product gas) × 100

The analysis of the source gas and the product gas was performed using a TCD gas chromatograph (GL Science GC-353B) and an FID gas chromatograph (GL Science GC-353B). Molecular sieve 13X for analysis of O ₂ and N ₂ , Unibeads C packed column (manufactured by GL Sciences) is used for analysis of CO and CO ₂ , and HP-AL / S capillary column for analysis of hydrocarbon compounds (Manufactured by Agilent Technologies) was used.

In the following table, C1 to C3 indicate the total of hydrocarbons having 1 to 3 carbon atoms, n-C ₄ H ₈ indicates n-butene, 1,3-C ₄ H ₈ indicates 1,3 -Refers to butadiene.

Claims (8)

An oxidative dehydrogenation catalyst for performing oxidative dehydrogenation of paraffins having 3 to 5 carbon atoms or monoolefins having 3 to 5 carbon atoms contained in a hydrocarbon raw material;
The hydrocarbon raw material is a hydrocarbon raw material containing a paraffin having 3 to 5 carbon atoms, a hydrocarbon raw material containing a monoolefin having 3 to 5 carbon atoms, or a paraffin having 3 to 5 carbon atoms and a monoolefin having 3 to 5 carbon atoms, A hydrocarbon feedstock containing
The oxidative dehydrogenation catalyst contains a vanadium atom, a magnesium atom, and a molybdenum atom, and the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles in terms of atoms of vanadium, magnesium, and molybdenum ((Mo / (V + Mg + Mo)) × 100) is 0.3 to 1.8 mol%,
An oxidative dehydrogenation catalyst.   In the X-ray diffraction analysis, the peak top intensity (x) of the diffraction peak at 2θ = 23.0 to 23.2 ° with respect to the peak top intensity (a) of the diffraction peak at 2θ = 42.9-43.1 °. The oxidative dehydrogenation catalyst according to claim 1, wherein the relative intensity ratio (x / a) is 0.04 or less.   A raw material mixture in which a vanadium source, a magnesium source and a molybdenum source are dissolved or dispersed in water is prepared, and then water in the raw material mixture is removed by evaporation to obtain a raw material mixture powder, 2. The oxidative dehydrogenation catalyst according to claim 1, wherein the oxidative dehydrogenation catalyst is obtained by firing the raw material mixture powder. An oxidative dehydrogenation catalyst for producing n-butene and 1,3-butadiene by oxidative dehydrogenation reaction from n-butane contained in a hydrocarbon raw material,
The oxidative dehydrogenation catalyst contains a vanadium atom, a magnesium atom, and a molybdenum atom, and the ratio of the number of moles of molybdenum in terms of atoms to the total number of moles in terms of atoms of vanadium, magnesium, and molybdenum ((Mo / (V + Mg + Mo)) × 100) is 0.3 to 1.8 mol%,
An oxidative dehydrogenation catalyst.   In the X-ray diffraction analysis, the peak top intensity (x) of the diffraction peak at 2θ = 23.0 to 23.2 ° with respect to the peak top intensity (a) of the diffraction peak at 2θ = 42.9-43.1 °. The oxidative dehydrogenation catalyst according to claim 4, wherein the relative intensity ratio (x / a) is 0.04 or less.   A raw material mixture in which a vanadium source, a magnesium source and a molybdenum source are dissolved or dispersed in water is prepared, and then water in the raw material mixture is removed by evaporation to obtain a raw material mixture powder, The oxidative dehydrogenation catalyst according to claim 4, wherein the oxidative dehydrogenation catalyst is obtained by firing the raw material mixture powder.   A raw material mixture in which a vanadium source, a magnesium source and a molybdenum source are dissolved or dispersed in water is prepared, and then water in the raw material mixture is removed by evaporation to obtain a raw material mixture powder, A method for producing an oxidative dehydrogenation catalyst, comprising calcining the raw material mixture powder.   Oxidation of paraffins having 3 to 5 carbon atoms or monoolefins having 3 to 5 carbon atoms contained in the hydrocarbon raw material at 400 to 700 ° C in the presence of the oxidative dehydrogenation catalyst according to any one of claims 1 to 3. It is an oxidative dehydrogenation reaction in which dehydrogenation is performed, and the hydrocarbon raw material is a hydrocarbon raw material containing paraffins having 3 to 5 carbon atoms, a hydrocarbon raw material containing monoolefins having 3 to 5 carbon atoms, or 3 to 5 carbon atoms. An oxidative dehydrogenation method comprising a hydrocarbon raw material containing paraffin and a monoolefin having 3 to 5 carbon atoms.

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