JP2005270895A - Oxidation reaction apparatus and its use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxidation reaction apparatus which has an oxygen separation element constituted so that an oxide ion conductive membrane-shaped ceramic body is supported by a porous support and has excellent efficiency when a hydrocarbon is oxidized. <P>SOLUTION: This oxidation reaction apparatus is provided with: the oxygen separation element 10 having the porous support 14 on one side of the oxide ion conductive ceramic body 12 formed into a dense membrane-like shape; a casing 3 for housing the element 10; an oxygen source supplying chamber 20 to which an oxygen source gas (such as air) is supplied; and an oxidation reaction chamber 30 to which the gas to be oxidized (such as CH<SB>4</SB>)is supplied. The membrane-shaped ceramic body 12 of the element 10 is arranged on the side of the oxygen source supplying chamber 20 and the porous support 14 is arranged on the side of the oxidation reaction chamber 30. A catalyst causing a carbonization reaction (such as a metal catalyst) is not placed at least in the position closer to the oxidation reaction chamber 30 than the membrane-shaped ceramic body 12 of the element 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an oxidation reaction apparatus that oxidizes a gas to be oxidized (for example, hydrocarbon gas) using an oxide ion conductor that selectively transmits oxide ions. The present invention also relates to an oxidation reaction method for oxidizing an oxidizable gas using an oxide ion conductor.

A ceramic (oxide ion conductor) having a property of selectively transmitting oxide ions (also referred to as oxygen ions) at a high temperature (for example, 500 ° C. or higher) is known. A ceramic body (oxide ion conductive ceramic body) made of such an oxide ion conductor can be used for the purpose of separating oxygen from a mixed gas containing oxygen. For example, an oxygen separation method using zirconium oxide as an oxide ion conductor is known.
On the other hand, some oxide ion conductors exhibit electronic conductivity (meaning including hole conductivity) as well as oxide ion conductivity. Such an oxide ion conductor is sometimes called an electron-oxide ion mixed conductor (hereinafter also simply referred to as “mixed conductor”). A film-like ceramic body composed of such a mixed conductor has an electronic conductivity, so that the ceramic body itself has an electronic conductivity. Oxide ions can be transmitted continuously.

  Such an oxide ion conductor can be suitably used as a component of an oxidation reaction apparatus that performs a partial oxidation reaction of hydrocarbons or the like. For example, this oxide ion conductor is formed into a film (including a thin layer), one surface of the film ceramic body is brought into contact with an oxygen source gas, and the other surface is hydrocarbon (methane). Etc.). Thereby, the hydrocarbon which contacted the other surface of the ceramic body can be oxidized by the oxide ion which permeate | transmits and supplies this ceramic body from one surface of a film-form ceramic body. In order to increase the efficiency of this oxidation reaction, a catalyst for promoting the oxidation reaction (typically, rhodium metal) is usually provided on the other surface of the ceramic body (the surface on the side in contact with the hydrocarbon as the gas to be oxidized). A metal catalyst such as a catalyst, a metal nickel catalyst, and a metal cobalt catalyst).

Moreover, in order to advance the hydrocarbon oxidation reaction as described above efficiently, it is effective to increase the amount of oxide ions that are supplied through the membranous ceramic body. One way to increase the supply amount of oxide ions (oxygen permeation amount) is to reduce the thickness of the membrane-like ceramic body to be used. Accordingly, the permeation distance of oxide ions is shortened, so that the oxygen permeation amount (oxygen separation ability) can be improved. However, if the thickness of the film-like ceramic body is set to a certain level or less, generally the mechanical strength of the ceramic body tends to be lowered, and cracks are likely to occur during its use. The cracked membranous ceramic body can no longer exhibit its original performance (performance of selectively transmitting oxide ions, etc.).
When a membrane ceramic body having oxide ion conductivity is used as a component of an oxidation reaction device, when this membrane ceramic body is used for simple oxygen separation (when used as a component of an oxygen separator). In comparison, it tends to be more difficult to reduce the thickness of the film-like ceramic body. This is because the surface of the ceramic body in contact with the oxidizable gas such as hydrocarbon is exposed to a reducing atmosphere, so that the conductor is easily reduced, and the crystal structure of the conductor is changed to easily reduce the strength. Is considered to be related to

Therefore, it has been proposed to support the oxide ion conductor with a porous support to ensure its strength. For example, Patent Document 1 describes a ceramic composite material having a structure in which a mixed conductor mainly composed of Sr, Fe and Co is supported by an oxide porous body mainly composed of magnesium. In the embodiment described in this document, when partial oxidation of methane gas is performed using the ceramic composite material, a metal catalyst such as a metal rhodium (Rh) catalyst or a metal nickel (Ni) catalyst is used as the oxidation promotion catalyst. Yes.
JP 2001-97789 A

However, even in a conventional oxidation reaction apparatus using an oxygen separation element having a structure in which a membranous ceramic body is supported by a porous support, it has been difficult to achieve practically sufficient oxidation efficiency. In addition, such an oxidation reaction apparatus may have an unstable oxidation efficiency (for example, the efficiency decreases when the operation is continued).
Accordingly, the present invention provides an oxidation reaction apparatus having an oxygen separation element having a structure in which a membrane-like ceramic body having oxide ion conductivity is supported by a porous support, and the oxidation efficiency of a gas to be oxidized (hydrocarbon etc.) An object of the present invention is to provide an oxidation reaction apparatus with good quality. Another object of the present invention is to provide an oxidation reaction method for efficiently oxidizing a gas to be oxidized using such an oxygen separation element. Another related object is to provide an oxygen separation element suitably used in such an oxidation reaction apparatus or an oxidation reaction method.

In the conventional general oxidation reaction method, as described above, a metal Ni catalyst, a metal Rh catalyst, and a metal Co catalyst are formed on the surface of the film-like ceramic body on the side of the oxidation reaction chamber (the side in contact with the gas to be oxidized such as hydrocarbon). The oxidation reaction is promoted by attaching a metal catalyst such as the above. In the oxygen separation element in which the membranous ceramic body is supported by the porous support, the metal catalyst may be attached to the porous support. However, since such a metal catalyst easily induces a carbonization reaction, if an oxidizable gas (hydrocarbon, etc.) containing carbon as a constituent element is oxidized using a metal catalyst, carbon deposition (coking) occurs during the oxidation reaction. (Sometimes called "coking"). For this reason, as shown in FIG. 15, the oxygen separation element 10 having a structure in which one surface side of the membranous ceramic body 12 is supported by the porous support 14 to which the metal catalyst 62 is attached, the support 14 is an oxidation reaction chamber. When arranged so as to be on the 30th side (the side on which hydrocarbons such as CH ₄ are circulated; hereinafter referred to as the “hydrocarbon side”), the fineness of the support 14 is reduced by the carbon deposited on the oxidation reaction chamber 30 side. The hole 142 is easily blocked. When such clogging (clogging) of the pores 142 proceeds, it becomes difficult for hydrocarbons (CH _{4 and the} like) supplied to the oxidation reaction chamber 30 to reach the membranous ceramic body 12 (oxide ion conductor and carbonization). The contact efficiency with hydrogen decreases.) As a result, the oxide ions that have permeated the membranous ceramic material 12 cannot be properly supplied to the hydrocarbon, and the oxidation efficiency of the hydrocarbon is reduced. For this reason, as shown in FIG. 15, the oxidation reaction apparatus including the element 10 having the structure in which the porous support 14 supporting the metal catalyst 62 is disposed on the oxidation reaction chamber 30 side performs oxidation of hydrocarbons when continuous operation is performed. Efficiency tends to decrease. This tendency becomes particularly remarkable when the porosity of the support 14 is relatively low, or when the average pore diameter (average pore diameter) of the support 14 is relatively small. On the other hand, if the porosity and / or average pore diameter of the support 14 is too large, it is difficult to appropriately form a thin (thin) film-like ceramic body 12 on the surface.

As described above, in the conventional technique, when the oxygen separation element is arranged with the porous support facing the hydrocarbon side (oxidation reaction chamber side), the oxygen permeability is improved by reducing the thickness of the ceramic body. It has been difficult to achieve both improvement in hydrocarbon contact efficiency (prevention of clogging) by increasing the porosity of the support. Therefore, conventionally, as shown in FIG. 10, for example, the side where the porous support 14 is formed in the oxygen separation element 10 is not the hydrocarbon side (oxidation reaction chamber 30 side), but the opposite side, that is, the oxygen source supply. In general, the element 10 is arranged so as to face the chamber 20 side (hereinafter sometimes referred to as “oxygen side”).
However, even in the configuration in which the oxygen separation element 10 is disposed with the porous support 14 facing the oxygen side, for example, when air is used as the oxygen source gas, the oxidation reaction efficiency as expected may not be obtained. there were. In addition, even if the porosity of the porous support 14 is increased in order to further improve the oxidation reaction efficiency, the oxygen permeation amount may not improve as expected.

  The present inventor arranges an oxygen separation element having a porous support material on one surface side of a membranous ceramic body so that the porous support body is on the oxidation reaction chamber side (side in contact with the oxidation target gas). In addition, the metal catalyst that has been used to improve the oxidation efficiency (a typical example of a catalyst that causes a carbonization reaction) is not supported inside the support, so that the metal catalyst is at least An attempt was made to provide an oxygen separation element having a configuration that does not exist on the hydrocarbon side (oxidation reaction chamber side) of the membrane-like ceramic body. As a result, the present inventors have found that it is possible to achieve hydrocarbon oxidation efficiency superior to that obtained when a metal catalyst is used, even though a metal catalyst is not used.

  That is, the oxidation reaction apparatus provided by the present invention includes an oxygen separation element having a porous support on one surface side of an oxide ion conductive ceramic body (film-like ceramic body) formed into a dense film. Moreover, the casing which accommodates the oxygen separation element can be provided. Moreover, the oxygen source supply chamber provided in the other surface side of the said film-like ceramic body can be provided in the casing. The oxygen source supply chamber is configured to be able to supply an oxygen source gas containing oxygen from the outside. In order to perform such supply, an oxygen source supply means for supplying the oxygen source gas to the oxygen source supply chamber can be provided. The casing further includes an oxidation reaction chamber that is provided on the one surface side of the membrane-like ceramic body and that is airtightly partitioned from the oxygen source supply chamber via the membrane-like ceramic body. be able to. The oxidation reaction chamber is configured to be able to supply a gas to be oxidized including a gas to be oxidized from the outside. In order to perform such supply, an oxidation target gas supply means for supplying the oxidation target gas to the oxidation reaction chamber can be provided. And it is comprised so that the said to-be-oxidized gas can be oxidized by the oxidation reaction which the oxide ion which permeate | transmits and supplies the said film-like ceramic body from the said oxygen source supply chamber side exists. In a preferred embodiment of the apparatus disclosed herein, a catalyst that causes a carbonization reaction (in particular, a rhodium (Rh) -based catalyst, a nickel (Ni) -based catalyst, a cobalt (Co) -based catalyst) is provided inside the support of the oxygen separation element. Etc.) is not supported.

According to the oxidation reaction device having such a configuration, a large amount of oxide ions can be supplied from the oxygen source supply chamber side (oxygen side) of the oxygen separation element to the oxidation reaction chamber side (hydrocarbon side). That is, a high oxygen permeation amount (oxide ion permeation ability) can be realized in the oxygen separation element (oxide ion conducting component). Therefore, according to the oxidation reaction apparatus constructed using such an oxygen separation element, the gas to be oxidized can be efficiently oxidized (typically partially oxidized). In other words, a gas containing the oxide can be efficiently produced from the gas to be oxidized such as hydrocarbon. For example, a mixed gas containing COx (preferably mainly carbon monoxide) and hydrogen (H ₂ ) can be efficiently produced from methane (CH ₄ ). In addition, the apparatus disclosed herein is a reaction that produces syngas (a gas containing H ₂ and CO in a volume ratio of 2: 1) from a raw material gas such as methane or natural gas, and a saturated or unsaturated low molecular weight. It is suitable as an apparatus for performing a hydrocarbon partial oxidation reaction such as a reaction for producing an unsaturated hydrocarbon (olefin, etc.) from a hydrocarbon (eg, ethane, propane, ethylbenzene, etc.).

  The oxygen source gas of the apparatus disclosed herein may be pure oxygen (refers to a gas consisting essentially of oxygen), and oxygen and other gas components (for example, an inert gas such as nitrogen). A mixed gas may be included. In the case of using a mixed gas as the oxygen source gas, the effect of applying the present invention to the prior art is particularly well exhibited. For example, it is preferable to use a mixed gas having an oxygen content of about 80% by volume or less (typically about 5 to 80% by volume), and about 50% by volume or less (typically about 5 to 50% by volume). It is more preferable to use a mixed gas of According to the apparatus of the present invention, even when such a mixed gas (typically air) is used as the oxygen source gas, good oxidation efficiency (high oxygen permeation amount in the oxygen separation element) can be realized.

  The porosity of the porous support constituting the oxygen separation element can be, for example, about 80% by volume or less (typically about 5 to 80% by volume). Usually, it is appropriate to set the porosity to about 60% by volume or less (typically, about 5 to 60% by volume). When the porosity of the porous support is in the range of about 5 to 60% by volume (more preferably 10 to 50% by volume), the effect of applying the present invention is particularly well exhibited. According to the apparatus of the present invention, even when a porous support having a porosity in the above range is used, a desired oxygen permeation amount (and hence the oxidation efficiency of the oxidant gas) can be ensured.

In a preferred embodiment of the device disclosed herein, the film-like ceramic body has a perovskite crystal structure. For example, a film-like ceramic body having a perovskite type crystal structure and a composition represented by the general formula Ln _1-x Ae _x MO ₃ is preferable. Here, Ln in the above general formula is one or more selected from lanthanoids. Ae is one or more selected from the group consisting of Sr, Ca and Ba. M is one or more selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. x is a number satisfying 0 ≦ x ≦ 1. A preferred example of Ln is La. A suitable example of Ae is Sr.
A film-like ceramic body having such a composition can exhibit good oxide ion conductivity and good electron conductivity. Therefore, an oxidation reaction device constructed using an oxygen separation element having such a membrane-like ceramic body does not use an external electrode that short-circuits the oxygen source supply chamber side surface and the oxidation reaction chamber-side surface of the membrane-like ceramic body. It can be configured. Moreover, it is good also as a structure using an external electrode.

In the above general formula, the number of oxygen atoms is indicated as 3, but in reality, the number of oxygen atoms is 3 or less (typically less than 3). However, since the number of oxygen atoms varies depending on the type of atom (for example, Ae) that replaces a part of the perovskite structure, the substitution ratio, and other conditions, it is difficult to display accurately. Therefore, in the present specification, in the general formula showing the perovskite type material, the number of oxygen atoms is indicated as 3 for convenience, but it is not intended to limit the technical scope of the invention taught here. Therefore, the number of oxygen atoms can be written as, for example, 3-δ (for example, the above general formula is expressed as Ln _1-x Ae _x MO _3-δ ). Here, δ is typically a positive number not exceeding 1 (0 <δ <1).
Preferred examples of the film-like ceramic body include those having a composition represented by the general formula _{(Ln 1-x Ae x)} (Bm 1-y Fe y) O 3. Here, Ln in the above general formula is one or more selected from lanthanoids. Ae is one or more selected from the group consisting of Sr, Ca and Ba. x is a number satisfying 0.2 ≦ x ≦ 0.8. Bm is Ga and / or Ti. y is a number satisfying 0.5 ≦ y ≦ 0.9. A preferred example of Ln is La. A suitable example of Ae is Sr.

In another preferred embodiment of the apparatus disclosed herein, the porous support constituting the oxygen separation element is a ceramic porous body having a perovskite crystal structure. Select Such preferred as the ceramic body, the general formula _{Ln 1-x Ae x MO 3} ( however, Ln is at one or more selected from lanthanoids, Ae from the group consisting of Sr, Ca and Ba And M is selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. X is a number satisfying 0 ≦ x ≦ 1)) Composite oxide having a perovskite type crystal structure with a composition represented by: stabilized zirconia; cerium oxide; aluminum oxide; One or more oxides selected from the group consisting of silicon; and magnesium oxide. Formula _{(Ln 1-x Ae x)} (Bm 1-y Fe y) O 3 composite oxide having a composition represented by mainly composed of a ceramic porous body is preferable. Here, Ln in the above general formula is one or more selected from lanthanoids. Ae is one or more selected from the group consisting of Sr, Ca and Ba. x is a number satisfying 0.2 ≦ x ≦ 0.8. Bm is Ga and / or Ti. y is a number satisfying 0.5 ≦ y ≦ 0.9. A preferred example of Ln is La. A preferred example of M is Sr.

In still another preferred embodiment of the apparatus disclosed herein, a general formula Ln _1-x Ae _x MO ₃ (where Ln is the same) is provided on the oxygen source supply chamber side surface (the side opposite to the support) of the membranous ceramic body. One or more selected from lanthanoids, Ae is one or more selected from the group consisting of Sr, Ca and Ba, and M is Fe, Mn, Ga, Ti, Co, Ni, 1 or 2 or more types selected from the group consisting of Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y, and x is a number that satisfies 0 ≦ x ≦ 1. And / or a composite oxide having a perovskite crystal structure and / or one or more metals selected from metal elements belonging to Groups 4 to 13 of the periodic table. Such a composite oxide and / or metal can function as a catalyst for promoting permeation of oxide ions (oxide ion permeation promoting catalyst). Therefore, oxygen separation which shows further better oxygen permeation performance by adopting a structure in which such a complex oxide and / or metal has a film-like ceramic body on the oxygen source supply chamber side surface (typically attached). It can be an oxidation reactor equipped with an element. The oxide ion permeation promoting catalyst is provided on the oxygen-side surface of the film-like ceramic body and does not substantially cause a carbonization reaction, so that the catalyst does not cause problems such as coking.

Any of the above-described apparatuses can be suitably used as a hydrocarbon oxidation reaction apparatus (typically, a hydrocarbon partial oxidation reaction apparatus). In this case, an oxidation target gas containing an oxidizable gas containing hydrocarbon as a main component may be supplied to the oxidation reaction chamber. For example, a step of circulating a gas containing oxygen in the oxygen source supply chamber and bringing it into contact with the surface of the ceramic body on the oxygen source supply chamber side, and a flow of an oxidation target gas containing hydrocarbon (for example, methane) in the oxidation reaction chamber It is suitable as an apparatus for carrying out a hydrocarbon oxidation reaction method (typically a hydrocarbon partial oxidation method) including a step of contacting the surface of the ceramic body with the oxidation reaction chamber side surface. Also, a mixed gas (for example, H ₂ and CO of 2: 1) containing an oxide thereof (typically a partial oxide such as carbon monoxide) and H ₂ from a hydrocarbon (natural gas, methane, etc.) It is suitable as an apparatus for carrying out a mixed gas production method for producing a synthesis gas contained in a volume ratio.
The apparatus disclosed here can also be used for olefin synthesis reaction, selective oxidation reaction, oxidative dehydrogenation reaction and the like. For example, using the apparatus disclosed herein, a reaction that produces unsaturated hydrocarbons (olefins, etc.) from saturated or unsaturated low molecular weight hydrocarbons (eg ethane, propane, ethylbenzene, etc.), isobutane to isobutene and / or Reactions that produce methacrylic acid, reactions that produce alkenes and / or alkynes from alkanes (eg, ethylene and / or acetylene from ethane), and the like can be performed. When performing such a reaction, the oxygen separation element is a catalyst that promotes the oxidation reaction on the oxidation reaction chamber side surface of the membranous ceramic body and / or the porous support, and substantially causes a carbonization reaction. It is suitable to use an oxidation reactor comprising a catalyst carrying no catalyst. As such an oxidation reaction promoting catalyst, metal / Mg—Al (for example, metal / MgAlO ₄ ), metal / MgO (for example, metal / MgO), metal / LaO (for example, metal / La ₂ O _3). ), One or two or more metals selected from metal elements belonging to Group 4 to Group 13 of the periodic table (excluding Ni, Co, Rh, and Pt), and the like. Also, in the apparatus for carrying out the above-described hydrocarbon oxidation reaction method (typically, a hydrocarbon partial oxidation method), a mixed gas production method, etc., such an oxidation reaction promoting catalyst (substantially the carbonization reaction is performed). A configuration including an oxygen separation element carrying a catalyst that does not occur can be preferably employed.

According to the present invention, using an oxygen separation element having a porous support on one surface side of an oxide ion conductive ceramic body (film-like ceramic body) formed into a dense film, an oxidizable gas such as a hydrocarbon. A method is provided for oxidizing. Here, as the oxygen separation element, an element in which a catalyst (typically a metal catalyst) causing a carbonization reaction is not supported on a portion closer to the support than the one surface side is used. And oxygen source gas (for example, air) containing oxygen is supplied to the other surface side of the film-like ceramic body. In addition, an oxidation target gas containing a gas to be oxidized (for example, a hydrocarbon such as methane) is supplied to one surface side (support side) of the film-like ceramic body. According to this method, a large amount of oxide ions can be supplied from the oxygen source supply chamber side of the oxygen separation element (oxide ion conducting component) to the oxidation reaction chamber side. Therefore, the gas to be oxidized such as hydrocarbon can be efficiently oxidized (typically partially oxidized). This method can be preferably applied to a mixed gas production method for efficiently producing a mixed gas (such as the above-mentioned synthesis gas) containing an oxide (typically a partial oxide) and H ₂ from a hydrocarbon. As the film-like ceramic body, those having a perovskite crystal structure can be preferably used.

In a preferred embodiment of such a method, an oxidation reaction is performed in which an oxidizable gas mainly composed of hydrocarbon is used, and oxide ions supplied from the oxygen source gas on the other surface side through the film-like ceramic body are supplied. Thus, the hydrocarbon is oxidized on the one surface side. For example, by using an oxidizable gas mainly composed of methane, an oxidation reaction mediated by oxide ions that are supplied from the oxygen source gas on the other surface side through the film-like ceramic body causes the one surface side to CO _x is generated from methane. This method is suitable, for example, as a method of producing a mixed gas containing COx (preferably mainly carbon monoxide) and hydrogen (H ₂ ) from methane.

  Hereinafter, preferred embodiments of the present invention will be described in detail. It should be noted that technical matters other than the contents particularly mentioned in the present specification and necessary for the implementation of the present invention can be grasped as design matters for those skilled in the art based on the prior art. The present invention can be carried out based on the technical contents disclosed in the present specification and the common general technical knowledge in the field.

The oxidation reaction apparatus or the oxidation reaction method disclosed herein is carried out using a predetermined oxygen separation element (oxide ion conductive component). The oxygen separation element has an oxide ion conductive ceramic body (film ceramic body) in which an oxide ion conductor is formed into a dense film. Moreover, it has the porous support body which supports the one surface side of the membranous ceramic body.
The membranous ceramic body constituting the oxygen separation element is formed of at least a ceramic exhibiting oxide ion conductivity (oxide ion conductor). It is preferably formed from a ceramic (mixed conductor) exhibiting oxide ion conductivity and electronic conductivity. A membrane-like ceramic body (oxygen separation membrane) formed from such a mixed conductor is continuous from one surface of the ceramic body to the other without using an electrode and an external circuit for short-circuiting both surfaces of the membrane. Thus, oxide ions can be transmitted. Therefore, a reactor constructed using an oxygen separation element having such a membrane-like ceramic body can be configured not to use external electrodes that short-circuit both surfaces of the ceramic body. Moreover, it is good also as a structure using an external electrode.

The film-like ceramic body preferably has a perovskite crystal structure. For example, a film-like ceramic body having a composition represented by the general formula Ln _1-x Ae _x MO ₃ can be preferably used. Here, Ln in the above general formula is one or more selected from lanthanoids, preferably Ln. Ae in the above general formula is one or more selected from the group consisting of Sr, Ca and Ba, and is preferably Sr. M in the above general formula is one selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. Two or more kinds, for example, Ti and / or Fe. “X” in the above general formula is a value indicating the ratio of Ln replaced by Ae in the perovskite structure having the composition represented by the above general formula. The value of x can be in the range of 0 ≦ x ≦ 1.

Preferred film-like ceramic body taken present invention has a perovskite crystal structure, include those having a composition represented by the general formula _{(Ln 1-x Ae x)} (Bm 1-y Fe y) O 3 . Ln in the above general formula is one or more selected from lanthanoids, preferably La. Ae in the above general formula is one or more selected from the group consisting of Sr, Ca and Ba, and is preferably Sr. Bm is Ga and / or Ti. The value of x can be in the range of 0.2 ≦ x ≦ 0.8, for example. From the viewpoint of enhancing oxide ion conductivity, a larger value of x is preferable. On the other hand, if the value of x is too large, cracks may easily occur in the ceramic material. A preferable range of x from the viewpoint of highly balancing durability and oxide ion conductivity is, for example, 0.2 ≦ x ≦ 0.6, and a more preferable range is 0.3 ≦ x ≦ 0.5. is there. Further, “y” in the above general formula is a value indicating the ratio of Bm replaced by Fe in this perovskite structure. The value of y can be in the range of 0.5 ≦ y ≦ 0.9 (more preferably, 0.6 ≦ y ≦ 0.8). If the value of y is too small (the ratio of Bm is too large), the conductivity of oxide ions may tend to decrease. On the other hand, if the value of y is too large, cracks are likely to occur.

  The porous support constituting the oxygen separation element (oxide ion conducting component) has stable heat resistance in the operating temperature range of the oxygen separation element (usually 300 ° C. or higher, typically 500 ° C. or higher). A material made of a material is preferably used. For example, a porous ceramic body having the same composition as any one of the above-described membrane-like ceramic bodies can be used. Moreover, the ceramic porous body comprised mainly by 1 type, or 2 or more types of oxides among stabilized zirconia, cerium oxide, aluminum oxide, silicon nitride, magnesium oxide, etc. may be sufficient. Alternatively, the porous support may be a porous metal body mainly composed of a metal porous body mainly composed of a metal material, a high heat resistant resin material (polyamide, polyamide-imide, polybenzimidazole, etc.). It may be used.

Preferable examples of the ceramic porous body include those composed mainly of a composite oxide having a perovskite crystal structure having a composition represented by the general formula Ln _1-x Ae _x MO ₃ . Here, Ln in the above general formula is one or more selected from lanthanoids, preferably Ln. Ae in the above general formula is one or more selected from the group consisting of Sr, Ca and Ba, and is preferably Sr. M in the above general formula is one selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. Two or more kinds, for example, Ti and / or Fe. For example, a porous ceramic body composed of the same kind of metal element as that of the film-like ceramic body (that is, the same kind of Ln and Ae) can be preferably used. In a preferred embodiment, the membranous ceramic body and the ceramic porous body (support) have substantially the same composition. In such a case, since not only the film-like ceramic body but also the support has oxide ion conductivity, the oxide ions can be supplied to the gas to be oxidized (hydrocarbon or the like) more efficiently. Also, having the general formula _{(Ln 1-x Ae x)} (Bm 1-y Fe y) perovskite crystal structure having a composition represented by _{O 3,} composed of a metal element of film-like ceramic body and the same type ( That is, the ceramic porous body (the same kind of Ln, Ae and Bm) can be preferably used. Thus, when the film-like ceramic body and the support have substantially the same composition, it is particularly preferable that Bm in the above general formula is Ti.
An oxygen separation element provided with such a ceramic porous body on the oxidation reaction chamber side (hydrocarbon side) of the membranous ceramic body can exhibit particularly good oxidation performance. For example, a gas to be oxidized containing hydrocarbons (oxidized gas) is supplied to an oxidation reaction apparatus constructed using such an oxygen separation element and continuously for a long time (for example, 3 hours or more, more preferably 6 hours or more). Even when the operation is performed, the oxidation efficiency of the hydrocarbon can be maintained in a good state (that is, the oxidation efficiency of the hydrocarbon and its stability are excellent).

  The oxygen separation element is plate-shaped (including planar and curved surfaces), tubular (including an open tube with both ends open, a closed tube with one end open and one closed), A porous support having a honeycomb shape or a combination thereof can be provided. An oxygen separation element having a structure in which a film-like ceramic body is formed (laminated) on one surface (typically, a surface orthogonal to the thickness direction of the support) of the support having such a shape can be used. Such an oxygen separation element includes a wall surface of a laminated structure that is asymmetric with respect to the thickness direction. Hereinafter, the oxygen separation element having such a configuration may be referred to as a “laminated oxide ion conducting component” or a “laminated ceramic component”. It is preferable to use a multilayer ceramic component having a structure in which a film-like ceramic body is formed on one surface of a plate-like, tubular or other film-like (layer-like) porous support (porous support layer). In a preferred example of the apparatus disclosed herein, such a multilayer ceramic component is placed in the casing, the porous support is directed to the oxidation reaction chamber side (hydrocarbon side), and the membranous ceramic body is directed to the oxygen source reaction chamber side (oxygen). Side). It is preferable that the surface on the other surface side (opposite side of the support) of the film-like ceramic body is exposed to the oxygen source supply chamber.

  In the oxygen source supply chamber of the oxidation reaction apparatus configured in this manner, air (a mixed gas containing oxygen at a ratio of approximately 20% by volume) as an oxygen source gas is circulated. Then, oxygen contained in the air (oxygen source gas) supplied to the oxygen source supply chamber becomes oxide ions and permeates the film-like ceramic body. Thereby, oxygen contained in the oxygen source gas (air) is selectively consumed in the oxygen source supply chamber (lost from the oxygen source supply chamber). At this time, as shown in FIG. 8, since the oxygen-side surface of the film-like ceramic body 12 faces (is exposed) the oxygen source supply chamber 20, new oxygen is quickly supplied to the vicinity of the surface. can do. Therefore, the decrease in oxygen partial pressure in the vicinity of the oxygen-side surface of the film-shaped ceramic body 12 is appropriately eliminated or alleviated.

  On the other hand, as shown in FIG. 10, in the configuration in which the oxygen separation element 10 is disposed with the porous support 14 facing the oxygen source supply chamber 20, the oxygen-side surface of the membrane-like ceramic body 12 is covered by the porous support 14. It has been broken. For this reason, unlike the configuration shown in FIG. 8, an atmosphere having a low oxygen partial pressure due to consumption (permeation) of oxygen tends to accumulate on the oxygen-side surface (inside the pores of the support) of the ceramic body 12. That is, it takes time for new oxygen to be supplied near the surface. In such a case, even if the oxygen separation ability of the ceramic body is increased by examining the ceramic composition or reducing the film thickness, the performance of the ceramic body cannot be fully exhibited. That is, in the configuration in which the porous support is directed to the oxygen source supply chamber side (oxygen side), the oxygen supply to the surface cannot catch up if the oxygen separation capability of the ceramic body increases. For this reason, the operation is continued under a condition where the oxygen partial pressure in the vicinity of the oxygen side surface is low, and the supply amount of oxide ions decreases. Therefore, in the oxidation reaction apparatus according to the present invention, as shown in FIG. 8, the oxygen separation element 10 is placed with the porous support 14 facing the oxidation reaction chamber 30 side (the side in contact with the gas to be oxidized such as hydrocarbon). Deploy.

  The film-like ceramic body constituting the oxygen separation element is preferably dense (for example, a relative density of 95% or more with respect to the theoretical density) and substantially gas-impermeable. The thickness of the film-like ceramic body (ceramic film) can be, for example, in the range of about 200 μm or less (typically about 5 to 200 μm), and in a preferred embodiment, the thickness is about 100 μm or less (typically about 5 to 100 μm). When the thickness of the membrane ceramic material is reduced (thinned), the permeation distance of oxide ions is shortened, so that the oxygen permeation amount (oxygen separation ability) can be improved. Here, in the oxygen separation element according to the present invention, one side of the membrane-like ceramic body (the oxidation reaction chamber side, that is, the side in contact with the gas to be oxidized) is supported by the porous support. Therefore, even when this membrane-like ceramic body is made relatively thin and used under conditions (reducing atmosphere) in contact with the gas to be oxidized, performance such as oxide ion permeability (conductivity) and the membrane-like ceramic body It is possible to balance the durability (hardness of cracking, etc.) at a high level.

The porosity of the porous support (for example, ceramic porous body) constituting the oxygen separation element can be, for example, about 80% by volume or less (typically about 5 to 80% by volume). From the viewpoint of mechanical strength and / or ease of manufacture of the oxygen separation element (for example, it means that a membranous ceramic body is easily formed on the surface of the porous support), the porosity of the porous support is Is about 60% by volume or less (typically about 5 to 60% by volume).
When the porosity of the porous support is in the range of about 5 to 60% by volume (more preferably about 10 to 50% by volume, more preferably about 10 to 40% by volume), the application effect of the present invention is particularly effective. Can be demonstrated well. Furthermore, it is possible to realize a sufficient oxygen permeation amount even when the porosity of the porous support is in the range of about 10 to 30% by volume. Thus, the porous support having a relatively low porosity has good mechanical strength. Moreover, a thinner film-like ceramic body can be appropriately formed on the surface of the support. Further, even when the thickness of the film-like ceramic body supported by the support is smaller (thin), the generation of cracks in the ceramic body and the peeling from the support can be well prevented or suppressed. Due to at least one of these effects, the porous support having a porosity in the above-mentioned range comprises a thinner membrane-like ceramic body (for example, approximately 100 μm or less) and constitutes an oxygen separation element having excellent durability. Can be.
Although it does not specifically limit, as a porous support body, what has an average pore diameter of 20 micrometers or less (typically 0.1-20 micrometers) can be used, for example. It is preferable to use a porous support having an average pore diameter of 3 μm or less (typically 0.5 to 3 μm). Such a porous support can appropriately form a thinner membranous ceramic body on the surface thereof. The porosity and average pore diameter of the porous support can be measured by, for example, a mercury intrusion method.
The thickness of the porous support is not particularly limited. For example, in the case of a planar or tubular porous support, the thickness can be in a range of about 0.5 to 50 mm, a more preferable range is about 1 to 20 mm, and a more preferable range is about 2 to 2. 10 mm, and a more preferable range is about 2 to 5 mm. By providing the thickness of the porous support within the above range, it is possible to provide an oxygen separation element that is excellent in mechanical strength and has good contact efficiency between the membranous ceramic body and the gas to be oxidized (for example, hydrocarbon). Can do.

An oxygen separation element having a membrane-like ceramic body represented by the above general formula Ln _1-x Ae _x MO ₃ and a porous support having substantially the same composition as the ceramic body is manufactured, for example, as follows. Can do.
First, a powder (porous body forming powder) for producing a porous support (ceramic porous body) is prepared. For example, a powder (raw material powder) of a compound containing metal atoms constituting the target ceramic porous body is mixed at a predetermined ratio (molar ratio). This mixture is shaped and fired in an oxidizing atmosphere (for example, in the air) or an inert gas atmosphere to obtain a fired product represented by the general formula Ln _1-x Ae _x MO ₃ . This can be crushed to prepare a powder for forming a porous body. At this time, the powder for forming a porous body having a desired particle diameter can be prepared by adjusting the crushing conditions or performing sieving (classification) as necessary. The porosity and / or average pore diameter of the ceramic porous body in the finally obtained oxygen separation element can be controlled by the average particle diameter of the porous body forming powder. Usually, it is appropriate that the average particle size of the porous body forming powder is in the range of about 1 to 150 μm, the preferable range is about 20 to 100 μm, and the more preferable range is about 40 to 100 μm. The porous body-forming powder having such an average particle diameter can easily produce an oxygen separation element suitable as a constituent element of the hydrocarbon oxidation reaction apparatus provided by the present invention.

The raw material powder includes an oxide containing a metal atom constituting the ceramic porous body or a compound that can be converted into an oxide by heating (a carbonate, nitrate, sulfate, phosphate, acetate, oxalic acid of the metal atom) Salts containing one or more of salts, halides, hydroxides, oxyhalides and the like) can be used. This raw material powder may contain a compound (a composite metal oxide, a composite metal carbonate or the like) containing two or more metal atoms among the metal atoms constituting the ceramic porous body.
Moreover, you may use the commercially available oxide powder etc. which have a composition represented by the said general formula as a powder for porous body formation as it is. Or you may use what granulated such an oxide powder, and calcined and made it grow to the desired particle size. The means for growing the particle size is not particularly limited. For example, the above-mentioned oxide powder is mixed with a predetermined amount of an additive such as a binder and a dispersant, kneaded well by a ball mill or the like, and dried to obtain an aggregate. The aggregate is calcined and, if necessary, pulverized, whereby a porous body-forming powder having a desired particle size can be obtained. Alternatively, a predetermined amount of an additive such as a binder, a dispersion medium, and a dispersing agent is added to the above oxide powder to form a slurry, followed by heating and drying with a spray dryer or the like to form a porous body having a desired particle size. Powder can be obtained.

Next, the porous body forming powder is formed into a molded body having a predetermined shape. As the molding method, various conventionally known methods such as uniaxial compression molding, isostatic pressing, and extrusion molding can be employed without particular limitation. A conventionally well-known binder etc. can be used for this shaping | molding. Also, a slurry or plastic solid containing the above powder can be prepared by appropriately using a binder, a dispersion medium, a dispersant, etc., and molded into a desired shape by a casting method, an extrusion molding method, an injection molding method, or the like. Good.
The molded body is fired to obtain a ceramic porous body. The temperature range (maximum firing temperature) at which the molded body is fired can be appropriately selected according to the composition of the membranous ceramic body (here, almost the same composition as the porous support). It is preferable to fire at a temperature range equal to or higher than the firing temperature of the film ceramic body. For example, when the firing temperature of the film-like ceramic body is 1200 to 1800 ° C., it is usually appropriate to fire at about 1200 to 1800 ° C., preferably about 1300 to 1700 ° C., preferably 1300 to 1600 ° C. More preferably, the temperature is about 1 ° C, and more preferably about 1400 to 1500 ° C. A suitable firing time may vary depending on the properties of the molded body. Usually, the firing time is suitably about 1 to 15 hours, preferably about 3 to 10 hours, and more preferably about 3 to 5 hours. In addition, in order to decompose and remove organic additives (for example, a binder, a dispersant, etc.) in advance and obtain uniform pores, one or more preliminary firings may be performed in advance before the main firing. This preliminary calcination is, for example, a temperature lower than that of the main calcination and capable of decomposing organic matter (for example, 100 to 1000 ° C., preferably about 200 to 500 ° C.), for example, for about 3 to 15 hours (preferably 8 About 12 hours). After the preliminary firing, the main firing is performed by raising the temperature to the maximum firing temperature. The rate of temperature increase is not particularly limited, but is usually 1 to 10 ° C / min, preferably 1 to 2 ° C / min. The firing atmosphere is preferably an oxidizing atmosphere or an inert gas atmosphere in which the oxide can be sintered.

In addition, powder (film-forming ceramic body forming powder) for forming (film-forming) a film-shaped ceramic body on the surface of the obtained ceramic porous body is prepared. For example, a compound powder (raw material powder) containing metal atoms constituting the target membranous ceramic body is mixed at a predetermined ratio (molar ratio). This mixture is shaped and fired in an oxidizing atmosphere (for example, in the air) or an inert gas atmosphere to obtain a fired product represented by the general formula Ln _1-x Ae _x MO ₃ . This can be crushed to prepare a powder for forming a film-like ceramic body. Usually, the average particle diameter of the powder is preferably in the range of about 1 to 30 μm, and more preferably in the range of about 1 to 15 μm. The powder having an average particle size in the above range is suitable for forming a dense film-like ceramic body on the surface of the ceramic porous body. Therefore, according to the powder for forming a film-like ceramic body having such an average particle size, an oxygen separation element suitable as a component of the oxidation reaction apparatus provided by the present invention can be easily produced.
As in the case of producing a ceramic porous body, the raw material powder is an oxide containing a metal atom (one or two or more) constituting a membranous ceramic body, or a compound that can be converted into an oxide by heating, or What contains 2 or more types can be used. Moreover, you may use the commercially available oxide powder etc. which have a composition represented by the said general formula as it is. Or what adjusted the particle size, such as such oxide powder, may be used. For example, commercially available oxide powders grown to a predetermined particle size, those pulverized to a predetermined particle size, and the like can be used.

Next, the film-form ceramic body-forming powder is applied to the porous support. As the application method, various methods used in conventionally known thin film forming processes can be employed. For example, a dip coating method, a spin coating method, a screen printing method, or a spray method using a slurry-like forming material in which the above powder is dispersed in a binder such as an organic solvent can be used. Among these, a dip coating method is preferable. The thickness of the film-shaped ceramic body to be formed is the concentration of the powder for forming the film-shaped ceramic body in the coating liquid, the type of additives such as a dispersant, a dispersion medium, and a plasticizer, the viscosity of the coating liquid, film-forming conditions, and drying conditions It is possible to control by adjusting these appropriately. Thereafter, the powder is fired to form a membranous ceramic body on the porous support. Preferred firing conditions may vary depending on the composition of the film-like ceramic body. From the viewpoint of forming a dense oxide film, it is usually appropriate to fire in an oxidizing atmosphere or an inert gas atmosphere at 1200 to 1800 ° C. Baking is preferably performed at a temperature equal to or lower than the baking temperature of the porous support described above. Thereby, the properties (porosity, average pore diameter, etc.) of the porous support in the finally obtained oxygen separation element can be better controlled.
In addition, one or two or more kinds selected from stabilized zirconia, cerium oxide, aluminum oxide, silicon nitride, magnesium oxide and the like according to the composition of the raw material powder to be used, by the same method as in the production of the ceramic porous body described above A ceramic porous body containing an oxide, or a ceramic porous body containing one or more of such oxides and a composite oxide represented by the general formula Ln _1-x Ae _x MO ₃ can be produced. . A membrane-like ceramic body represented by the general formula Ln _1-x Ae _x MO ₃ can be similarly formed on such a ceramic porous body to produce an oxygen separation element.

  In the oxygen separation element provided in the apparatus disclosed herein, a catalyst that causes a carbonization reaction (typically, a metal catalyst such as a nickel-based catalyst, a rhodium-based catalyst, or a cobalt-based catalyst) is substantially included in the support. Does not exist. Accordingly, for example, as shown in FIG. 15, the structure according to the present invention is different from the configuration in which the element 10 is arranged with the porous support 14 to which the metal catalyst 62 or the like is attached facing the oxidation reaction chamber 30 side. It is possible to avoid clogging of the support due to. Therefore, it can be an apparatus that can stably maintain good oxidation efficiency even in continuous operation for a long time (for example, 3 hours or more, preferably 6 hours or more) (no significant decrease in oxidation efficiency is observed). For example, even after 6 hours of continuous operation, it is possible to maintain an oxidation efficiency corresponding to about 80% or more immediately after the start of operation.

This oxygen separation element can be configured to have a “catalyst that promotes permeation of oxide ions”. Examples of the oxide ion permeation promoting catalyst (hereinafter sometimes simply referred to as “permeation promoting catalyst”) include LaSrCoO ₃ , LaSrFeO ₃ , LaSrCoFeO ₃ , LaCoO ₃ , LaBaCo, SeFeO ₃ , and SmSrCo. One kind or two or more kinds of conventionally known oxide ion conductors such as CaTiO ₃ can be used. Among these, a permeation promoting catalyst preferably used is CaTiO ₃ or Ln _1-x Ae _x MO ₃ (where Ln is one or more selected from lanthanoids, and Ae is a group consisting of Sr, Ca and Ba). And M is selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. 1 or 2 or more selected, and x is a number satisfying 0 ≦ x ≦ 1)). Particularly preferred catalysts include (La _z Sr _1-z ) CoO ₃ (where 0.1 ≦ z <1).

Such a permeation promoting catalyst can be disposed at any location selected from the oxygen side surface, hydrocarbon side surface, porous support and the like of the membranous ceramic body. It is particularly preferable that the permeation promoting catalyst is supported (attached) on the oxygen side (oxygen source supply chamber side) surface of the membranous ceramic body. What has the said permeation | transmission acceleration | stimulation catalyst adhered (coat) so that substantially the whole oxygen side surface may be covered can be used preferably. Alternatively, the catalyst may be attached only to a partial region (for example, in the form of dots, stripes, lattices, etc.). The method for attaching the catalyst to the surface of the ceramic material is not particularly limited. For example, the target catalyst can be attached (coated) by adjusting a slurry containing catalyst powder, applying the slurry to the surface of the ceramic material, and drying the slurry. Thereafter, the attached catalyst powder may be further fired.
A metal catalyst mainly composed of one or more metals selected from the group consisting of Pt, Pd, Ru, Au, Ag, Bi, Ba, V, Mo, Ce, Pr, Co, Rh and Mn is also used. It can function as a catalyst that promotes permeation of oxide ions. When such a metal catalyst is used as the permeation promoting catalyst, it is particularly preferable to dispose the catalyst only on the oxygen side surface of the membranous ceramic body (not on the hydrocarbon side).

  Next, a preferred configuration of the oxidation reaction apparatus will be described. This apparatus includes one or more oxidation reaction modules in which the oxygen separation element is accommodated in a casing. In this casing, an oxygen source supply chamber and an oxidation reaction chamber are formed that are hermetically partitioned from each other via a membrane-like ceramic body constituting the oxygen separation element. The number of elements accommodated in one module may be one, or two or more. The number of oxygen source supply chambers and oxidation reaction chambers provided in one module may be one or two or more. The number of oxygen source supply chambers and the number of oxidation reaction chambers provided in one module may be the same or different. As the oxygen separation element accommodated in such an oxidation reaction module, an element having an oxide ion permeation promoting catalyst attached to the oxygen side surface of the membranous ceramic body is preferable.

The apparatus disclosed herein can include oxygen source supply means for supplying a gas containing oxygen to the oxygen source supply chamber so as to contact the oxygen-side surface of the film-shaped ceramic body. The gas supplied by this means (oxygen source gas) typically contains 5 to 100% by volume of oxygen. A gas having an oxygen content of about 5 to 80% by volume (more preferably about 5 to 50% by volume, more preferably about 10 to 30%) may be supplied. When supplying an oxygen source gas having such a composition, the effect of applying the present invention can be exhibited particularly well. The oxygen source gas preferably used is air. The atmosphere (pressure of the oxygen source gas) in the oxygen source supply chamber when the apparatus is used may be normal pressure (atmospheric pressure), or may be pressurized or reduced pressure. Typically, it is normal pressure or pressurization, preferably normal pressure.
Note that the composition of the gas supplied to the oxygen source supply chamber by the oxygen source supply means is not limited to the above range, and for example, a gas (pure oxygen) substantially consisting of oxygen may be supplied. Moreover, you may supply the gas whose oxygen content is lower than the range mentioned above. For example, when oxygen in the supply gas is removed using the apparatus disclosed herein, the apparatus can be operated by supplying a gas having a low oxygen content from the oxygen source supply means.

  Further, the apparatus disclosed herein supplies an oxidation target gas supply means for supplying an oxidation target gas containing a gas to be oxidized (for example, hydrocarbon) to the oxidation reaction chamber so as to contact the oxidation reaction chamber side surface of the film-shaped ceramic body. Can be provided. The composition of the oxidizable gas can be appropriately selected depending on the kind and composition of the target oxidation reaction product. For example, an oxidation target gas having a composition containing one or more selected from low molecular weight hydrocarbons such as methane, ethane, propane, and ethylbenzene can be used. Alternatively, natural gas may be used as the gas to be oxidized. In a preferred embodiment, the main component of the gas to be oxidized is a hydrocarbon. For example, an oxidation target gas containing such an oxidizable gas (hydrocarbon or the like) at a ratio of about 10% by volume or more (typically about 10 to 100% by volume) can be used. It is preferable to use an oxidation target gas having an oxidizable gas content of about 40% by volume or more, and more preferably about 80% by volume or more. In addition, an oxidation target gas (for example, methane gas) in which the content ratio of the gas to be oxidized is substantially 100% by volume can be preferably used. The atmosphere in the oxidation reaction chamber during use of the apparatus may be any of normal pressure, pressurization, and reduced pressure.

The apparatus having such a configuration can typically be used under the following conditions. That is, the preferable temperature of the film-like ceramic body when performing the hydrocarbon oxidation reaction is usually 300 ° C. or higher (typically 300 to 1500 ° C.), preferably 500 ° C. or higher (typically 500 to 1500 ° C.). ), More preferably 800 ° C. or higher (typically 800 to 1200 ° C.). The flow rate of the oxygen source gas supplied to the oxygen source supply chamber by the oxygen source supply means can be, for example, in the range of about 10 mL to 300 L / min (preferably about 50 mL to 200 Lml / min). Of the oxygen source gas supplied to the oxygen source supply chamber, the flow rate of oxygen (oxygen supply flow rate) is preferably in the range of about 10 mL to 150 L / min (preferably 50 mL to 100 L / min). The flow rate of the oxidation target gas supplied to the oxidation reaction chamber by the oxidation target gas supply means (for example, a hydrocarbon gas cylinder and a valve connected thereto) is, for example, 5 mL to 300 L / min (preferably 5 mL to 200 L / min). min). Of the gas to be oxidized supplied to the oxidation reaction chamber, the flow rate of the gas to be oxidized (for example, hydrocarbon such as methane) is preferably in the range of 5 mL to 150 L / min (more preferably 5 mL to 100 L / min).
According to the above apparatus, for example, at 900 ° C., oxygen of 10 ml or more per unit area (cm ² ) of the ceramic material (in terms of oxygen molecules in a standard state) permeates from the oxygen source supply chamber side to the oxidation reaction chamber side. Thus, it can be used for an oxidation reaction of an oxidizable gas such as hydrocarbon. In a more preferred embodiment, oxygen of 20 ml / min / cm ² or more can be permeated from the oxygen source supply chamber side to the oxidation reaction chamber side.

According to the oxidation reaction apparatus provided by the present invention, a mixed gas containing COx (preferably mainly carbon monoxide) and hydrogen (H ₂ ) from an oxidizable gas such as methane or natural gas (for example, H ₂ and It is possible to efficiently carry out a reaction for producing a synthesis gas containing CO in a volume ratio of 2: 1. Therefore, according to the other aspect of this invention, the manufacturing apparatus and manufacturing method which manufacture the said mixed gas from raw material gas, such as methane and a natural gas, are provided. Further, according to this apparatus, a partial hydrocarbon oxidation reaction such as a reaction for generating unsaturated hydrocarbons (olefins, etc.) from saturated or unsaturated low molecular weight hydrocarbons (eg ethane, propane, ethylbenzene, etc.) can proceed efficiently. be able to.
The composition and flow rate of the gas supplied to the oxidation reaction chamber of such an oxidation reaction apparatus, the composition of the ceramic constituting the ceramic material, the presence / absence and type of the oxidation promoting catalyst, the reaction temperature, etc. are appropriately set.
Note that any of the above-described apparatuses can be used as a reaction apparatus or the like for another oxidation reaction involving oxide ions. For example, an oxidation reaction such as oxidation of a reducing gas other than hydrocarbon (generation of H ₂ O by oxidation of hydrogen gas, etc.), substitution of an aromatic compound, etc. can be performed. Further, this apparatus can be used as an oxygen separation apparatus.

Hereinafter, several forms of the oxidation reaction apparatus provided by the present invention will be described by taking as an example the case of supplying an oxidation target gas containing hydrocarbons. The apparatus exemplified here includes an oxidation reaction module including an oxygen separation element, a casing that accommodates the element, and an oxygen source supply chamber and an oxidation reaction chamber formed in the casing.
FIG. 1 is a schematic view illustrating an oxidation reaction module using an oxygen separation element formed in a flat plate shape. This oxidation reaction module 2 accommodates an oxygen separation element (laminated oxygen ion conducting component) 10 having a flat porous support 14 on one surface side of an oxygen separation membrane (membrane ceramic body) 12 and the element 10. The casing 3 is provided. The casing 3 includes an outer tube 36 connected to one surface side (porous support 14 side) of the element 10, an inner tube 34 inserted into the outer tube 36, and the other surface side (oxygen separation membrane) of the element 10. 12) and an inner tube 24 inserted into the outer tube 26. The inner tubes 24 and 34 and the outer tubes 26 and 36 are all made of a dense ceramic (here, alumina) such as alumina or mullite. A glass seal 11 is formed in a ring shape on the outer periphery of the element 10. The glass seal 11 hermetically seals one end of the outer pipes 26 and 36 to the element 10 and hermetically seals the outer peripheral end of the element 10. On the oxygen separation membrane side of the element 10, an oxygen source supply chamber 20 is defined by the element 10 and the outer tube 26. Further, an oxidation reaction chamber 30 is defined by the element 10 and the outer tube 36 on the porous support side of the element 10. An oxide ion permeation promotion catalyst (for example, a LaSrCoO ₃ permeation promotion catalyst) (not shown) is attached to the surface (surface 12a shown in FIG. 2) of the oxygen separation membrane 12 constituting the element 10 on the oxygen source supply chamber 20 side. ing. The element 10 does not have a metal catalyst.

FIG. 2 is a schematic diagram showing a hydrocarbon oxidation reaction apparatus 1 constructed using the module 2 having such a configuration. In this apparatus 1, the oxygen source supply chamber 20 of the module 2 is used to circulate air through the oxygen source supply chamber 20 to contact the oxygen source supply chamber side (oxygen side) surface 12 a of the oxygen separation membrane 12. An oxygen source supply means 52 is connected. As shown in FIG. 1, the oxygen source supply means 52 is constructed so that oxygen source gas (here, air) can be supplied to the oxygen source supply chamber 20 through the inner tube 24. On the other hand, as shown in FIG. 2, in the oxidation reaction chamber 30 of the module 2, the surface of the oxygen separation membrane 12 on the oxidation reaction chamber side (hydrocarbon side) is made to flow through the oxidation reaction chamber 30. A hydrocarbon gas (oxidation target gas) supply means 54 for contacting with 12b is connected. As shown in FIG. 1, the hydrocarbon gas supply means 54 is constructed so that hydrocarbons (here, CH ₄ ) can be supplied to the oxidation reaction chamber 30 through the inner pipe 34. In addition, the apparatus 1 shown in FIG. 2 includes a heating means (such as a heater) 56 for heating the oxygen separation element 10 (particularly the oxygen separation membrane 12) to a desired temperature.
While maintaining the oxygen separation membrane 12 at a predetermined use temperature (for example, 500 ° C. or more) by the heating unit 56, air (Air) and CH ₄ are circulated to the module 2 by the oxygen source supply unit 52 and the oxidation target gas supply unit 54. Let As a result, oxygen in the air supplied to the oxygen source supply chamber 20 receives electrons on the oxygen side surface (exposed surface) 12a of the oxygen separation membrane 12 and becomes oxide ions, and these oxide ions become oxygen separation membranes. 12 diffuses into the hydrocarbon side surface 12b, where it contacts with CH ₄ to oxidize it, producing reactants such as CO, CO ₂ and H ₂ . In this way, the hydrocarbon oxidation reaction (here, the partial oxidation reaction of methane) is performed.

Note that the oxidation reaction module 1 shown in FIG. 1 may be configured such that the inner tube 24 is omitted and an oxygen source gas (for example, air) is directly introduced into the oxygen source supply chamber 20. Similarly, the inner pipe 34 may be omitted, and the oxidation target gas may be directly introduced into the oxidation reaction chamber 30. Further, in the oxidation reaction module 1 shown in FIG. 1, one oxygen separation element 10 formed in a flat plate shape is used. However, as shown in FIG. 3, a plurality of flat plate element 10 are stacked and adjacent elements are arranged. The oxidation reaction module may be configured such that air (oxygen source gas) and CH ₄ (oxidation target gas) are alternately circulated through the flow paths formed between the channels 10. At this time, the module 1 may be constructed such that the oxygen separation membrane 12 of each element 10 faces the air flow path and the porous support 14 is positioned on the CH ₄ flow path side.

FIG. 4 is an example of the oxidation reaction module 2 using the tubular oxygen separation element 10. The element 10 includes a porous support 14 formed into a tubular shape, and a membrane-like ceramic body (oxygen separation membrane) 12 provided on the outer surface of the tube. The element 10 is accommodated in the casing 42 to constitute the module 2. The casing 42 has a hollow cylindrical shape and is formed of a dense ceramic such as mullite or alumina. The tubular (open tubular) element 10 penetrates the both ends of the casing 42 in the axial direction. In the penetrating portion, the element 10 and the casing 42 are hermetically sealed by a glass sealing or the like (not shown). Two through holes 43 and 44 are formed in the side surface of the casing 42. In the oxidation reaction module 2, an oxidation reaction chamber 30 is defined in the tubular element 10 by the element 10 itself. A cylindrical oxygen source supply chamber 20 is defined by the casing 42 and the element 10 (oxygen separation membrane 12). This oxidation reaction module 2 can be used in the apparatus 1 shown in FIG. 2 instead of the oxidation reaction module shown in FIG.
In addition, in the oxidation reaction module 2 shown in FIG. 4, one element 10 formed in a tubular shape (open tube) is used. However, as shown in FIG. 5, a plurality of tubular elements 10 are arranged in the axial direction of the casing 42. Alternatively, the oxidation reaction module 2 may have a structure with a through hole. In the oxidation reaction module 2 having such a structure, the inside of each element 10 is used as the oxidation reaction chamber 30, and the space between the casing 42 and the element 10 is used as the oxygen source supply chamber 20. In FIG. 5, the oxygen separation membrane 12 formed on the outer surface of each element 10 is omitted.

In the oxidation reaction module 2 shown in FIGS. 4 and 5, the element 10 whose both ends are open passes through the casing 42, but as shown in FIG. 6, the element whose one end (tip) is closed in the casing 42. It can also be set as the structure provided with (closed tubular element) 10. The number of the closed tubular elements 10 provided in one casing 42 may be one, or two or more. FIG. 6 illustrates a configuration including one element 10. According to this configuration, it is possible to reduce the number of seal points between the element 10 and the casing 42 as compared with a configuration in which the open tubular element 10 penetrates the casing 42. For this reason, it can be set as the oxidation reaction module 2 with the favorable sealing performance of the casing 42. FIG. It is good also as a structure which has arrange | positioned the inner tube | pipe 34 which both ends opened as shown in FIG. 6 inside a closed tubular element. As the inner tube 34, one formed from a dense ceramic such as mullite or alumina can be used. The distal end of the inner tube 34 extends to the vicinity of the distal end of the closed tubular element 10. Further, a cylindrical gap is formed between the inner periphery of the closed tubular element 10 and the outer periphery of the inner tube 34. A gas to be oxidized (hydrocarbon such as CH ₄ ) is supplied into the inner pipe 34, and the gap is circulated from the tip of the inner pipe 34. Accordingly, CH ₄ can be brought into contact with oxide ions that are supplied from the air flowing outside the element 10 through the oxygen separation membrane 12. Alternatively, the inner pipe 34 may be omitted.

Further, as shown in FIG. 7, an oxygen permeation module can be configured by using the element 10 formed in a honeycomb shape. The element 10 includes a porous support 14 that is formed in a honeycomb shape and has a cylindrical outer shape as a whole. A plurality of flow paths 15 partitioned from each other by porous partition walls 13 are formed in the honeycomb support 14 so as to penetrate the element 10 in the axial direction. These flow paths 15 include a flow path 15a (oxygen source supply chamber) for circulating the oxygen source gas and a flow path 15b (oxidation reaction chamber) for flowing the oxidation target gas containing hydrocarbons such as CH _4. It is roughly divided into The flow paths 15a and 15b are alternately arranged. An oxygen separation membrane (not shown) is provided on the surface of the partition wall 13 on the side of the flow path 15a forming the oxygen source supply chamber. The oxidation reaction module including such an element 10 is used as a component of the apparatus 1 shown in FIG. 2 so that the oxygen source gas and the oxidation target gas are circulated through the flow paths 15a and 15b. it can.

  Hereinafter, some experimental examples relating to the present invention will be described, but the present invention is not intended to be limited to those shown in the experimental examples.

<Experimental Example 1: Production of porous support>
Commercially available La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ powder was mixed with a binder and a dispersant, and well kneaded using a ball mill. Then, it dried at 100 degreeC for 24 hours, and obtained the aggregate of the same composition. The aggregate was calcined and crushed. By adjusting the crushing conditions, five kinds of raw material powders having different average particle diameters were obtained. The average particle size of these raw material powders is in the range of about 5 to 10 μm. The particle size of the raw material powder was measured using a laser diffraction particle size distribution meter, and the average particle size was determined together.
Next, each of the obtained La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ raw material powder was mixed with a binder and a dispersant, and well kneaded using a ball mill. Then, it dried at 100 degreeC for 24 hours, and obtained the aggregate of the same composition. The agglomerates were each crushed by a ball mill and pressed into a disk shape having a diameter of about 20 mm and a thickness of about 3 mm by press extrusion under a pressure of 100 MPa using a press extruder. The obtained molded body was first heated to 200 to 500 ° C. in the air and kept at the same temperature for 10 hours to decompose and remove organic substances. Thereafter, the temperature was raised to 1500 ° C. in the atmosphere, and the compact was fired by maintaining the same temperature for 3 hours. In this manner, five types of porous support Nos. Having different porosities were used. 1-No. 5 was produced. The porosity of these porous supports is about 30% by volume (No. 1), about 20% by volume (No. 2), about 15% by volume (No. 3), and about 10% by volume (No. 4). ), About 5% by volume (No. 5). The average pore diameters of these porous supports are about 10 μm (No. 1), about 7 μm (No. 2), about 5 μm (No. 3), about 4 μm (No. 4), and about 2 μm, respectively. No. 5).

<Experimental example 2: Formation of oxygen separation membrane>
Porous support No. 1 prepared in Experimental Example 1 An oxygen separation membrane having the same composition as that of the support (La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ ) was formed on one surface of 1 (porosity; about 30% by volume). .
That is, a commercially available La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ powder having an average particle size of about 1 μm was prepared as a powder for forming a membrane-like ceramic body (oxygen separation membrane). This powder was well kneaded using a ball mill together with water, a binder and a dispersant as a dispersion medium. As a result, a film-forming slurry containing La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ powder was prepared. In the obtained slurry, the porous support No. 1 prepared in Experimental Example 1 was used. One side of 1 was dipped (immersed) for 20 seconds. Thereby, the slurry was uniformly laminated on the surface portion of the porous support. Thereafter, the porous support was pulled up from the slurry and dried at 60 ° C. for 4 hours. This was first heated to 200 to 500 ° C. in the atmosphere, and kept at the same temperature for 10 hours to decompose and remove organic substances. Furthermore, the temperature was raised to 1500 ° C. in the atmosphere, and the slurry was fired while maintaining the same temperature for 3 hours. This was allowed to cool, and an oxygen separation element No. 1 having an oxygen separation membrane (La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ membrane) on the surface portion on one side of the porous support. 1 was obtained.
In addition, the support No. In place of support No. 1 In the same manner as described above except that 2 to 5 were used, an oxygen separation membrane (La _0.6 Sr _0.4 Ti _0.3 Fe _0.7 O ₃ membrane) was formed on the surface portion on one side of the porous support. Oxygen separation element No. 2 to 5 were obtained.
These element Nos. The thicknesses of the oxygen separation membranes constituting 1 to 5 were all about 60 μm as measured by electron microscope (SEM) observation.

<Experimental Example 3: Support of oxide ion permeation promoting catalyst>
Element No. obtained in Experimental Example 2 For 1 to 5 (no catalyst), an oxide ion permeation promoting catalyst was supported on the exposed surface side of the oxygen separation membrane (that is, the side opposite to the side supported by the porous support). That is, a commercially available La _0.8 Sr _0.2 CoO ₃ powder (particle size: about 2 μm) was mixed by adding water, a binder and a dispersant as a dispersion medium, and kneaded well using a ball mill. Was prepared. Then, element No. The slurry was evenly applied to the exposed surfaces of the oxygen separation membranes 1 to 5 and dried. Furthermore, in an air atmosphere, the temperature was raised to 1000 ° C. at a rate of 1 ° C./min using an electric furnace, and the slurry was fired by holding at this temperature for 1 hour.
Thus obtained oxygen separation element with catalyst No. 1 was obtained. The configuration of 1A to 5A is schematically shown in FIG. This element 10 has a configuration in which the one surface 12 b side of the oxygen separation membrane 12 is supported by a porous support 14. An oxide ion permeation promoting catalyst 64 is supported on the exposed surface 12 a of the oxygen separation membrane 12. On the other hand, no catalyst is supported on the porous support 14 and the support-side surface 12 b of the oxygen separation membrane 12.

<Experimental Example 4: Evaluation of oxygen permeation performance>
Element No. with catalyst obtained in Experimental Example 3 1A to 5A were used as oxygen separation elements, respectively, to produce an oxidation reaction module 2 having the configuration shown in FIG. A hydrocarbon oxidation reaction apparatus 1 as shown in FIG. 2 was constructed using these modules 2. The oxygen separation element 10 (oxygen separation membrane 12) is heated to about 900 ° C., air as an oxygen source gas is supplied to the oxygen source supply chamber 20 at a flow rate of about 200 ml / min, and the oxidation reaction chamber 30 is supplied. Methane gas (CH ₄ ) as an oxidation target gas was supplied at a flow rate of about 100 ml / min. That is, as shown in FIG. 8, air was supplied to the oxygen separation membrane 12 side of the element 10 and CH ₄ was supplied to the porous support 14 side.
A continuous operation for 3 hours was performed under the above conditions. During this time, the composition of the gas discharged from the oxidation reaction chamber 30 was measured by a gas chromatograph. Of these, the oxygen permeation amount at 900 ° C. (standard) from the amount of chemical species containing oxygen (here, substantially CO, CO ₂ and O ₂ ) and the area of the oxygen permeation portion of the oxygen separation membrane 12 constituting the element 10. State of oxygen molecule conversion; ml / min / cm ² ) was calculated. The result is shown in FIG.
As can be seen from this figure, for example, when the target level of oxygen permeation performance (oxygen permeation amount) is 10 ml / min / cm ² , according to the apparatus configuration and operating conditions of this experimental example, the porosity of the support is 10 volumes. The target level could be achieved even with a relatively low element (No. 4A) of about%. Element No. provided with a support having a higher porosity (for example, 15% by volume or more). Even better results were obtained when 1A-3A was used.

<Experimental Example 5: Loading of oxide ion permeation promoting catalyst and oxidation promoting catalyst>
Element No. obtained in Experimental Example 2 An oxide ion permeation promoting catalyst was supported on 1 to 5 (no catalyst) porous support. That is, a commercially available La _0.8 Sr _0.2 CoO ₃ powder (particle size: about 2 μm) was mixed by adding water, a binder and a dispersant as a dispersion medium, and kneaded well using a ball mill. Was prepared. Then, element No. The slurry was impregnated with the porous support constituting 1 to 5 for 3 hours and then dried at 100 ° C. for 5 hours. Furthermore, in an air atmosphere, the temperature was raised to 1000 ° C. at a rate of 1 ° C./min using an electric furnace, and the slurry was fired by holding at this temperature for 1 hour.
Furthermore, a metal catalyst (in this case, a nickel catalyst) as an oxidation promotion catalyst was supported on the exposed surface side of the oxygen separation membrane. That is, nickel oxide powder having an average particle size of about 5 μm was dispersed in water to prepare a slurry. The slurry was evenly applied to the surface of the oxygen separation membrane and dried. Furthermore, in an air atmosphere, the temperature was raised to 1000 ° C. at a rate of 1 ° C./min using an electric furnace, and the slurry was fired by holding at this temperature for 1 hour.
Thus obtained oxygen separation element with catalyst No. 1 was obtained. The configuration of 1B to 5B is schematically shown in FIG. This element 10 has a configuration in which the one surface 12 b side of the oxygen separation membrane 12 is supported by a porous support 14. An oxide ion permeation promoting catalyst 64 is supported on the porous support 14. A metal catalyst 62 is supported on the exposed surface 12 a of the oxygen separation membrane 12.

<Experimental Example 6: Evaluation of oxygen permeation performance>
Element No. with catalyst obtained in Experimental Example 5 1B to 5B, as shown in FIG. 10, the elements 10 are arranged so that the support 14 is on the oxygen source supply chamber 20 side and the oxygen separation membrane 12 is on the oxidation reaction chamber 30 side, and hydrocarbon oxidation is performed. A reactor was constructed. The element 10 (oxygen separation membrane 12) is heated to about 900 ° C., air is supplied to the porous support 14 side at a flow rate of about 200 ml / min, and CH ₄ is supplied to the oxygen separation membrane 12 side at about 100 ml / min. It was supplied at a flow rate of min. Under these conditions, continuous operation was performed for 3 hours, and the oxygen permeation amount was calculated in the same manner as in Experimental Example 4. The result is shown in FIG.
As can be seen from FIG. 11, in the apparatus configuration and operating conditions of this experimental example (unlike Experimental example 4 shown in FIG. 9), even if the porosity of the support constituting the element is increased, this is not the case. The transmission performance was not reflected much. For this reason, the above target level could not be achieved in the range tested this time (the porosity of the support is 30% by volume or less).

<Experimental Example 7: Evaluation of oxygen permeation performance>
In Experimental Example 6, air was supplied to the porous support 14 side (oxygen source supply chamber 20). However, in this experimental example, pure oxygen was supplied to the porous support 14 side at about 200 ml / min as shown in FIG. The flow rate was The oxygen permeation amount was calculated in the same manner as in Experimental Example 6 for other points. The result is shown in FIG.
As can be seen from FIG. 13, in the apparatus configuration and operating conditions of this experimental example (unlike Experimental example 6 shown in FIG. 11), the oxygen permeation performance improved smoothly by increasing the porosity of the support. This result suggests that the improvement in oxygen permeation performance in Experimental Example 6 is related to the use of a mixed gas (air) as the oxygen source gas. That is, in the apparatus of Experimental Example 6, since the element 10 is arranged so that the porous support 14 is on the oxygen source supply chamber 20 side as shown in FIG. 10, the oxygen-side surface 12 b of the oxygen separation membrane 12. It is considered that the oxygen consumed in the above could not be sufficiently replenished, and the oxygen concentration in the vicinity of the surface 12b was thereby lowered, thereby preventing the improvement of the oxygen permeation performance.

  Element No. with catalyst in which the porosity of the porous support is about 30% by volume. 1A and element No. with catalyst From 1B, the oxygen permeation amount obtained in Experimental Example 4, Experimental Example 6, and Experimental Example 7 and the results of these experimental examples are given by the following formula: [Amount of methane contained in gas discharged from oxidation reaction chamber] / Table 1 summarizes the methane conversion calculated by [amount of methane supplied to the oxidation reaction chamber 30]. As can be seen from Table 1, according to the apparatus configuration of Experimental Example 4, although oxygen is used as the oxygen source supply gas in the same manner as Experimental Example 6, the oxygen permeation performance is significantly higher than that of Experimental Example 6 ( Oxygen transmission rate) and methane conversion rate could be realized.

In addition, element No. with catalyst obtained in Experimental Example 5 was used. As shown in FIG. 14, the element 10 is placed in the direction opposite to that of Experimental Example 6 (that is, the oxygen separation membrane 12 is on the oxygen source supply chamber 20 side and the support 14 is on the oxidation reaction chamber 30 side). The oxygen permeation amount and the methane conversion rate were calculated in the same manner as in Experimental Example 6 except for the arrangement point. The oxygen permeation rate was about 0.1 ml / min / cm ² and the methane conversion rate was about 10%. .
Element No. obtained in Experimental Example 2 1 (no catalyst) was used, and element No. 1 with a catalyst having the configuration shown in FIG. 1C was produced. That is, the oxide ion permeation promoting catalyst 64 is supported on the exposed surface 12a of the oxygen separation membrane 12 of the element 10, and the oxidation promoting catalyst 62 (the same nickel catalyst used in Experimental Example 5) is further supported on the porous support 14. Supported. This element 10 was arranged such that the support 14 was on the oxidation reaction chamber 30 side and the oxygen separation membrane 12 was on the oxygen source supply chamber 20 side, thereby constructing a hydrocarbon oxidation reaction apparatus. When CH ₄ was supplied to the support 14 side and air was supplied to the oxygen separation membrane 12 side, the oxygen permeability was greatly reduced within 1 hour from the start of operation. Therefore, when the element 10 was removed from the apparatus and observed, it was found that the pores 142 of the support 14 were blocked by the deposition of carbon (coking).

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
In addition, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

It is typical sectional drawing which shows the principal part in one structural example of an oxidation reaction apparatus. It is a schematic diagram which shows schematic structure of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part in the other structural example of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part in the other structural example of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part in the other structural example of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part in the other structural example of an oxidation reaction apparatus. It is a typical perspective view which shows the principal part in the other structural example of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part of an oxidation reaction apparatus. It is a characteristic view which shows the relationship between the porosity of a support body, and oxygen transmission amount. It is typical sectional drawing which shows the principal part of an oxidation reaction apparatus. It is a characteristic view which shows the relationship between the porosity of a support body, and oxygen transmission amount. It is typical sectional drawing which shows the principal part of an oxidation reaction apparatus. It is a characteristic view which shows the relationship between the porosity of a support body, and oxygen transmission amount. It is typical sectional drawing which shows the principal part of an oxidation reaction apparatus. It is typical sectional drawing which shows the principal part of an oxidation reaction apparatus.

Explanation of symbols

1: Oxidation reaction device 2: Oxidation reaction module 3: Casing 10: Oxygen separation element (stacked oxide ion conductive component)
12: Membrane ceramic body (oxygen separation membrane)
14: Porous support 142: Pore 20: Oxygen source supply chamber 30: Oxidation reaction chamber 52: Oxygen source gas supply means 54: Oxidation target gas supply means 56: Heating means 62: Metal catalyst 64: Oxide ion permeation promotion catalyst

Claims (11)

An oxygen separation element having a porous support on one side of an oxide ion conductive ceramic body formed into a dense membrane;
A casing that houses the element;
An oxygen source supply chamber that is provided on the other surface side of the film-like ceramic body in the casing and is supplied with an oxygen source gas containing oxygen from the outside,
An object to be oxidized, which is provided on the one surface side of the film-shaped ceramic body in the casing and is airtightly separated from the oxygen source supply chamber via the film-shaped ceramic body. An oxidation reaction chamber in which gas is supplied from the outside and oxidizes the gas to be oxidized by an oxidation reaction through which oxide ions are supplied through the film-like ceramic body from the oxygen source supply chamber side;
Here, an oxidation reaction apparatus characterized in that a catalyst that causes a carbonization reaction is not supported on a portion of the element that is closer to the support than the membrane ceramic body. Oxygen source supply means for supplying the oxygen source gas to the oxygen source supply chamber;
Oxidation target gas supply means for supplying the oxidation target gas to the oxidation reaction chamber;
The apparatus of claim 1, further comprising:   The apparatus according to claim 2, wherein the porosity of the porous support is in the range of 5 to 60% by volume.   The apparatus according to claim 1, wherein the film-like ceramic body is a ceramic having a perovskite crystal structure. The film-like ceramic body has a perovskite-type crystal structure, and has a general formula Ln _1-x Ae _x MO ₃ (where Ln is one or more selected from lanthanoids, and Ae is Sr, Ca and One or more selected from the group consisting of Ba, and M is Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y. The device according to claim 1, wherein the device has a composition represented by: one or more selected from the group consisting of x and x satisfying 0 ≦ x ≦ 1. The porous support comprises the following oxides:
General formula Ln _1-x Ae _x MO ₃ (where Ln is one or more selected from lanthanoids, Ae is one or more selected from the group consisting of Sr, Ca and Ba, M is one or more selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y, and x Is a number satisfying 0 ≦ x ≦ 1, and a composite oxide having a perovskite crystal structure having a composition represented by:
Stabilized zirconia;
Cerium oxide;
Aluminum oxide;
Silicon nitride; and
Magnesium oxide;
The device according to claim 5, which is a porous ceramic body having one or more oxides selected from the group consisting of: On the oxygen source supply chamber side surface of the film-like ceramic body,
General formula Ln _1-x Ae _x MO ₃ (where Ln is one or more selected from lanthanoids, Ae is one or more selected from the group consisting of Sr, Ca and Ba, M is one or more selected from the group consisting of Fe, Mn, Ga, Ti, Co, Ni, Al, In, Sn, Zr, V, Cr, Zn, Ge, Sc, and Y, and x Is a number satisfying 0 ≦ x ≦ 1) and / or a composite oxide having a perovskite crystal structure having a composition represented by:
The apparatus of Claim 1 which has a 1 type, or 2 or more types of metal selected from the metal element which belongs to periodic table group 4 thru | or 13 group.   The apparatus according to claim 1, wherein a main component of the gas to be oxidized is hydrocarbon, and is used as an oxidation reaction apparatus for the hydrocarbon. An oxygen separation element having a porous support on one surface side of an oxide ion conductive ceramic body formed into a dense membrane, wherein the support does not carry a catalyst that causes a carbonization reaction. A method for oxidizing an oxidizable gas using:
An oxidation reaction method in which an oxygen source gas containing oxygen is supplied to the other surface side of the film-like ceramic body, and an oxidation target gas containing the gas to be oxidized is supplied to one surface side of the film-like ceramic body.   The main component of the oxidizable gas is hydrocarbon, and the carbonization is performed on the one surface side by an oxidation reaction mediated by oxide ions supplied from the oxygen source gas on the other surface side through the film-like ceramic body. The method according to claim 9, wherein hydrogen is oxidized. The main component of the gas to be oxidized is methane, and from the methane on the one surface side by an oxidation reaction mediated by oxide ions that are supplied from the oxygen source gas on the other surface side through the film-like ceramic body. The method of claim 9, wherein COx and H ₂ are produced.

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