JP2007115521A - Electrochemical micro-coil reactor and electrochemical reaction system composed of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small and highly reliable electrochemical micro-coil reactor and an electrochemical reaction system using the same. <P>SOLUTION: The electrochemical micro-coil reactor is composed of an electrochemical reactor cell having a structure in which a hollow tube coil structure made of an anode (a fuel electrode) material is laminated with an ion conductor (an ion conductor layer) and a cathode (an air electrode) is laminated on the above coil. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrochemical microcoil reactor and an electrochemical reaction system such as a solid oxide fuel cell composed of the microcoil reactor, and more specifically, for example, a microtube cell having a tube diameter of 2 mm or less. Even so, a cell stack can be easily fabricated and handled, a structure capable of sufficiently securing an air passage can be constructed, and the electrolyte is made thinner and the surface area per unit surface is greatly increased. Thus, the present invention relates to an electrochemical microcoil reactor having a new structure capable of lowering the operating temperature to 400 to 650 ° C. and an electrochemical reaction system using the same. The present invention provides, for example, new technologies and new products relating to electrochemical reactors suitably used as clean energy sources and environmental purification devices.

  As a typical electrochemical reactor, there is a solid oxide fuel cell (hereinafter referred to as “SOFC”). The SOFC is a fuel cell using a solid oxide electrolyte having ionic conductivity as an electrolyte. The basic structure of the SOFC is usually composed of three layers of cathode-solid oxide electrolyte-anode, and the SOFC is usually used in a temperature range of 800 to 1000 ° C.

  For example, when fuel gas (hydrogen, carbon monoxide, hydrocarbon, etc.) is supplied to the anode of SOFC and air, oxygen, etc. are supplied to the cathode, the oxygen partial pressure on the cathode side and the oxygen partial pressure on the anode side Therefore, a voltage according to the Nernst equation is generated between the electrodes. Oxygen becomes ions at the cathode and moves to the anode side through the solid electrolyte, and the oxygen ions reaching the anode react with the fuel gas and release electrons. Therefore, if a load is connected to the anode and cathode of this SOFC, electricity can be directly taken out as a fuel cell.

  In the future, in order to put SOFC into practical use, it is essential to lower the operating temperature of SOFC. By reducing the operating temperature to 800 ° C. or lower, particularly 500 to 600 ° C., use of inexpensive materials and a reduction in operating cost can be expected, and the versatility of SOFC is expected to increase by lowering the operating temperature. Further, in the low temperature operating region, the SOFC characteristics are greatly dependent on the electrode structure, and for the structural control, it is also an important factor to reduce the process temperature in the SOFC manufacturing process.

  In order to lower the operating temperature of the SOFC, it is inevitable to make the electrolyte thin, and so far, electrode support type cells, particularly anode support type cells, have been widely studied (Non-patent Document 1). . In addition, it is expected that further miniaturization of SOFC will lead to the production of new markets such as use as an auxiliary power source for automobiles and portable power sources. For this purpose, it is necessary to improve the cell surface area per unit volume, and an SOFC structure composed of tubular cells has also been proposed (Patent Document 1).

  However, the tubular cells proposed so far have a structure in which the tube cells are stably held by the cathode material, and packing of the tubular cells becomes difficult as the tube diameter becomes smaller. There was a problem. In addition, this structure has problems such as difficulty in securing an air gas channel and the need to use a large amount of expensive cathode material.

JP 2004-335277 A Nikkei Mechanical separate volume, fuel cell development forefront, Nikkei BP, June 29, 2001, p. 71-80

  Under such circumstances, in view of the prior art, the present inventors can easily integrate even a microtube having a tube diameter of 2 mm or less and sufficiently secure an air passage. As a result of intensive research aiming to develop a new structure that can be made, the tube is structured in a coil shape, and the outside and inside of the coil are made into air passages, and the surface area per unit volume is effective as a tube As a result, the present invention was completed.

  An object of the present invention is to provide an electrochemical microcoil reactor in which the operating temperature can be lowered by using a new tube structure in which a ceramic hollow tube is structured in a coil shape. Another object of the present invention is that it is possible to easily produce a cell stack by integration even in the case of a microtube cell having a tube diameter of 2 mm or less, and is necessary for the conventional tube structure. The object is to provide a novel structure of an electrochemical microcoil reactor that makes it possible to reduce the amount of cathode material used. Furthermore, an object of the present invention is to provide an electrochemical reaction system such as a solid oxide fuel cell using the electrochemical microcoil reactor.

The present invention for solving the above-described problems comprises the following technical means.
(1) It has a structure in which a ceramic hollow tube is wound in a coil shape, an electrolyte layer (ion conduction phase) formed on the surface, and a cathode (air electrode) laminated on the electrolyte layer of the coil. Electrochemical microcoil reactor, characterized by
(2) The electrolyte material contains two or more elements selected from Zr, Ce, Mg, Sc, Ti, Al, Y, Ca, Gd, Sm, Ba, La, Sr, Ga, Bi, Nb, and W. The electrochemical microcoil reactor according to (1), wherein the electrochemical microcoil reactor is an oxide compound.
(3) The hollow tube is made of an electrolyte material and an element selected from Ni, Cu, Pt, Pd, Au, Ru, Co, La, Sr, and / or an oxide compound containing one or more of these elements. The electrochemical microcoil reactor according to (1), which is configured.
(4) The cathode (air electrode) material is an element selected from Ag, La, Sr, Mn, Co, Fe, Sm, Ca, Ba, Ni, Mg and / or an oxide containing one or more of these elements. The electrochemical microcoil reactor according to (1), comprising a compound.
(5) The electrochemical microcoil reactor according to (4), wherein the cathode material is a transition metal perovskite oxide or a composite of a transition metal perovskite oxide and a solid electrolyte material.
(6) The electrochemical microcoil reactor according to (1), wherein the electrolyte layer has a thickness of 1 to 100 microns.
(7) The electrochemical microcoil reactor according to (1), wherein the tube diameter of the ceramic hollow tube is 2 mm or less.
(8) The electrochemical microcoil reactor according to any one of (1) to (7), wherein the operating temperature can be lowered to 400 to 650 ° C.
(9) An electrochemical reaction system for extracting an electric current by an electrochemical reaction, comprising the electrochemical microcoil reactor according to any one of (1) to (8) as a reactor. .
(10) The electrochemical reaction system according to (9) above, wherein units in which a plurality of electrochemical microcoil reactors are combined are stacked.
(11) The electrochemical reaction system according to (8) or (9), which is a solid oxide fuel cell, a hydrogen production reactor, or an exhaust gas purification reactor.

Next, the present invention will be described in more detail.
The electrochemical microcoil reactor of the present invention has a structure in which a ceramic hollow tube is wound in a coil shape, a dense electrolyte layer (ion conduction phase) formed on the surface thereof, and a laminate on the electrolyte layer of the coil. It has a cathode (air electrode).

  Conventionally, when producing a tube-type electrochemical cell, an anode material is produced as a tube (usually including sintering at 1400 ° C. or higher), and an electrolyte is laminated and sintered (usually at 1400 ° C. or higher). In addition, a plurality of process steps were required in which a tube was placed on the cathode structure and further sintered (usually 1000 ° C. or higher).

  Further, when the tube diameter is a microtube having a diameter of 2 mm or less, the process step becomes more difficult. However, according to the configuration of the electrochemical microcoil reactor, first, a coil-like structure is produced by a tube, so that a structure that can be easily handled even with a microtube having a tube diameter of 2 mm or less is obtained. Since the diameter can be arbitrarily changed, the air passage can be easily designed.

  Moreover, according to the said structure, a cathode material can be laminated | stacked by the required amount on the electrolyte layer on a coil, and it becomes possible to construct | assemble the electrochemical microcoil reactor excellent in cost performance. Examples of the electrochemical reaction system using the electrochemical microcoil reactor include a solid oxide fuel cell (SOFC), an exhaust gas purification electrochemical reactor, a hydrogen production reactor, and the like. Therefore, it is possible to construct a highly efficient SOFC by appropriately selecting materials for the anode, the electrolyte, and the cathode.

  In the present invention, the electrolyte material is required to be a material having high ionic conductivity, Zr, Ce, Mg, Sc, Ti, Al, Y, Ca, Gd, Sm, Ba, La, Sr, Ga. , Bi, Nb, and W are desirably oxide compounds containing two or more kinds of elements.

  The hollow tube preferably contains a material having high activity with respect to the fuel gas. The electrolyte material, Ni, Cu, Pt, Pd, Au, Ru, Co, La, Sr, Ti, and / or Alternatively, it is necessary and important for realizing a highly efficient electric chemical reactor to be composed of one or more kinds of oxidized compounds.

  Further, the cathode (air electrode) material is preferably a material having high activity for ionization of oxygen, and in particular, elements of Ag, La, Sr, Mn, Co, Fe, Sm, Ca, Ba, Ni, Mg and / or oxidation. A material composed of one or more compounds is preferred.

  Next, an electrochemical microcoil reactor according to an embodiment of the present invention and an electrochemical reaction system composed thereof will be described in detail. First, the configuration of the electrochemical microcoil reactor according to the present invention will be described. FIG. 1 is a schematic view of an electrochemical microcoil reactor according to the present invention. As shown in FIG. 1, an anode 2 made of a ceramic hollow tube having a dense electrolyte layer 1 is formed in a coil shape. And the electrochemical microcoil reactor is constructed | assembled by arrange | positioning the cathode 3 outside the electrolyte layer.

  First, the electrolyte layer 1 will be described. The thickness of the electrolyte layer 1 needs to be determined in consideration of the tube diameter of the porous tube, the specific resistance of the solid electrolyte layer itself, and the like. The electrolyte layer 1 is dense and preferably has a thickness in the range of 1 to 100 microns, and preferably 50 microns or less in order to suppress the electric resistance of the electrolyte. Since this electrolyte is laminated on the anode tube surface, it is possible to easily reduce the thickness. Normally, under the conditions of use as a fuel cell, a fuel gas such as hydrogen, carbon monoxide, methane or the like is supplied to the tube hole 4, and an oxidant gas such as air or oxygen is supplied to the coil hole 5. Is done.

  Here, in the electrochemical microcoil reactor according to the present invention, the tube diameter, tube length, and tube thickness of the tube are not particularly limited, and the entire size of the required electrochemical microcoil reactor is considered. However, it can be arbitrarily set so as to obtain the required characteristics as the anode. The tube porosity is preferably, for example, 30 to 70%, and more preferably 40% or more, but the three-phase interface (reaction field) is maintained and the tube strength is high. Various controls can be performed so as not to decrease.

  As the electrolyte material, it is necessary to use a material that realizes high ion conduction. As materials used for these, Zr, Ce, Mg, Sc, Ti, Al, Y, Ca, Gd, Sm, An oxide compound containing two or more elements selected from Ba, La, Sr, Ga, Bi, Nb, and W is exemplified as a desirable one.

Among them, stabilizers such as yttria (Y ₂ O ₃ ), calcia (CaO), scandia (Sc ₂ O ₃ ), magnesia (MgO), ytterbia (Yb ₂ O ₃ ), erbia (Er ₂ O ₃ ), etc. Preferable examples include stabilized zirconia that is stabilized, ceria (CeO ₂ ) doped with yttria (Y ₂ O ₃ ), gadolinia (Gd ₂ O ₃ ), samaria (Sm ₂ O ₃ ), and the like. The stabilized zirconia is preferably stabilized by one or more kinds of stabilizers, and is preferably a composite with alumina (Al ₂ O ₃ ).

  Specifically, yttria-stabilized zirconia (YSZ) added with 5 to 10 mol% yttria as a stabilizer, gadolinia doped ceria (GDC) added with 5 to 10 mol% gadolinia as a dopant, and the like are preferable examples. Can be mentioned. For example, in the case of YSZ, it is not preferable that the yttria content is less than 5 mol% because the oxygen ion conductivity of the anode is lowered. On the other hand, if the yttria content exceeds 10 mol%, the oxygen ion conductivity of the anode similarly decreases, which is not preferable. The same applies to GDC.

  The tube needs to be a composite composed of a mixture of anode material and electrolyte material. The anode material is a metal selected from Ni, Cu, Pt, Pd, Au, Ru, Co, La, Sr, Ti and / or an oxide composed of one or more of these elements, and is used as a catalyst. Specifically, nickel (Ni), cobalt (Co), ruthenium (Ru) and the like can be cited as suitable examples. Among these, nickel (Ni) can be suitably used because it is less expensive than other metals and has a sufficiently high reactivity with fuel gas such as hydrogen. It is also possible to use a composite in which these elements and oxides are mixed.

  Here, in the composite of the anode material and the electrolyte, the mixing ratio of the former and the latter is preferably in the range of 90:10 wt% to 40:60 wt%, and the balance of electrode activity, thermal expansion coefficient consistency, etc. More preferably, it is in the range of 80:20 wt% to 50:50 wt%. On the other hand, the cathode material is preferably a material having high activity for ionization of oxygen, and in particular, Ag, La, Sr, Mn, Co, Fe, Sm, Ca, Ba, Ni, Mg, and / or oxidation thereof. A material composed of one or more physical compounds is preferred.

  Among them, for example, transition metal perovskite oxides and composites of transition metal perovskite oxides and electrolyte materials can be preferably used. In the case of using a composite, oxygen ion conductivity is improved among the electron conductivity and oxygen ion conductivity, which are necessary characteristics of the cathode, so that oxygen ions generated at the cathode are easily transferred to the electrolyte layer. Thereby, there is an advantage that the electrode activity of the cathode is improved.

  Here, when a composite of a transition metal perovskite oxide and a solid electrolyte material is used, the mixing ratio of the former and the latter is preferably in the range of 90:10 wt% to 70:30 wt%, and electrode activity and thermal expansion From the viewpoint of excellent balance such as coefficient consistency, the range of 90:10 wt% to 80:20 wt% is more preferable.

Specific examples of the transition metal perovskite oxide include LaSrMnO ₃ , LaCaMnO ₃ , LaMgMnO ₃ , LaSrCoO ₃ , LaCaCoO ₃ , LaSrFeO ₃ , LaSrCoFeO ₃ , LaSrNiO ₃ Co, and SmS ₃ Can be mentioned.

  However, as shown in FIG. 1, the electrolyte layer 1 is not laminated on both ends of the porous tube, and an exposed portion of the anode 2 is formed by exposing a part of the anode tube. ing. The exposed portion of the anode 2 functions as an external lead electrode for the anode. The exposure amount of the exposed portion of the anode 2 is not particularly limited, and can be appropriately adjusted in consideration of a gas sealing member, a current collecting method for electrodes, a gas outlet channel, and the like.

  Next, an embodiment for operating the electrochemical microcoil reactor according to the present invention as a single SOFC and its operating method will be described. As shown in FIG. 2, the anode exposed portions are arranged in the fuel introduction pipes 8a and 8b, and the exposed portions of the anode 2 are sealed in the fuel introduction pipes 8a and 8b by gas sealing materials 9a and 9b. Specific examples of the main material constituting the fuel gas introduction unit include heat-resistant stainless steel and ceramics, which are preferable examples depending on the operating conditions of the SOFC.

That is, the exposed part of the anode 2 of the electrochemical microcoil reactor is mounted inside the fuel introduction pipes 8a and 8b, and the connection part of each electrode is sealed with the sealing materials 9a and 9b. As the material of the sealing materials 9a and 9b, any material can be used as long as it does not allow gas permeation, and is not particularly limited. However, it is necessary to use a material that matches the thermal expansion coefficient of the anode portion. Specifically, for example, ceramics such as mica glass and spinel (MgAl ₂ O ₄ ) are preferable examples.

A current collector 11 is attached to the electrode surface (the exposed portion of the anode 2 or the cathode 3). Specific examples of the main material constituting the current collector 11 include conductive ceramics such as lanthanum chromite (LaCrO ₃ ), noble metal meshes such as gold, silver and platinum, stainless steel, nickel mesh, nickel felt, and the like. Is a suitable example.

  Further, using an oxidant gas or fuel gas introduction means (for example, an external manifold), the fuel gas 6 is introduced into the anode part, the oxidant gas is introduced from the coil hole, and the pipe connection part and the current collector 11 are introduced. Further, by connecting the load 12 via the current collecting wires 10a and 10b, power generation is possible.

  In the above case, the embodiment of operating the electrochemical microcoil reactor according to the present invention as a single SOFC and the operating method thereof have been described. However, the operating method is not particularly limited. It can be appropriately operated as a hydrogen production electrochemical reactor, an exhaust gas purification reactor or the like. Further, a unit in which the electrochemical microcoil reactors according to the present invention are assembled in parallel is used as a unit, and a power generation apparatus can be constructed by stacking a plurality of these units.

  Next, the operation of the electrochemical microcoil reactor according to the present invention will be described. In the electrochemical microcoil reactor according to the present invention, a dense electrolyte layer is laminated on a hollow tube-shaped anode, the tube is formed as a coil structure, and the cathode is formed outside the electrolyte layer. .

  Conventionally, production of a cell stack using cells having a tube diameter of 2 mm or less has been difficult due to the difficulty in handling. However, according to the configuration of the electrochemical microcoil reactor, first, since a coiled structure is produced by a tube, not only a tube having a tube diameter of 2 mm or more but also a microtube having a tube diameter of 2 mm or less can be easily obtained. A handleable structure can be obtained, and the coil diameter can be changed arbitrarily, so that the air passage can be easily designed. The present invention includes a tube having a diameter of 2 mm or more, and the present invention is not particularly limited with respect to the tube diameter. Further, according to the above configuration, the cathode material can be stacked in a necessary amount on the electrolyte layer on the coil, thereby enabling to construct an electrochemical microcoil reactor excellent in cost performance. .

  Next, the suitable manufacturing method of the electrochemical microcoil reactor based on this invention is demonstrated. The method for producing an electrochemical microcoil reactor according to the present invention is basically characterized by including the following steps. That is, the method for producing an electrochemical microcoil reactor according to the present invention includes a step of manufacturing an anode tube, a step of bonding a solid electrolyte layer to the outer surface of the anode tube, a step of winding these tubes, and a coil structure. And applying a cathode to the outside of the solid electrolyte layer and sintering. Hereinafter, these will be described in detail.

  First, an anode tube is made using a mixture of anode material and electrolyte material. Specifically, an oxide containing two or more elements selected from Zr, Ce, Mg, Sc, Ti, Al, Y, Ca, Gd, Sm, Ba, La, Sr, Ga, Bi, Nb, and W To the powder of the compound and a metal element or oxide powder selected from Ni, Cu, Pt, Pd, Au, Ru, Co, La, Sr, and Ti, a pore-forming agent such as a cellulose-based binder or carbon powder is added. Then, a tubular molded body having a predetermined tube diameter, tube length, and tube thickness is formed using an extrusion method or the like by kneading with water and using the obtained plastic mixture.

  Next, after the slurry containing the electrolyte material powder is adhered to the obtained tube molded body, it is preferably wound on a roll and dried, for example. As a result, an electrolyte layer forming layer that becomes a solid electrolyte layer by subsequent firing adheres to the surface of the tube, and a coil structure is obtained in which the tubes are joined by the electrolyte layer. The drying method and means are not particularly limited, and appropriate methods and means can be used.

  Examples of the method for attaching the slurry include a method in which openings on both ends of a porous tube are sealed with a resin adhesive, and then the tube is immersed in a slurry containing a solid electrolyte and dip coated. A suitable example is given. In addition to the dipping method, various adhesion methods such as a brush coating method and a spray method can be used.

  At this time, it is necessary that an exposed portion in which the anode portion is exposed is formed at one end of the outer surface of the obtained tube with the electrolyte layer without adhering the slurry containing the solid electrolyte. This is fired at a predetermined temperature to obtain a coil structure with an electrolyte layer. The firing temperature of the coil structure is preferably fired at a temperature of about 1200 to 1600 ° C., but is not particularly limited, and the electrolyte layer becomes dense considering the tube material, porosity, and the like. The temperature can be set as appropriate. Further, the coil length and the coil diameter are not particularly limited, and can be appropriately determined according to the designed stack shape.

  A cathode material is then applied to the electrolyte layer. As the material, in particular, a material composed of one or more of Ag, La, Sr, Mn, Co, Fe, Sm, Ca, Ba, Ni, and Mg and / or an oxide compound thereof is suitable. A slurry can be produced from this powder, and the cathode can be formed on the electrolyte layer using a method similar to the method for preparing the solid electrolyte.

  Next, the obtained tube is fired at a predetermined temperature to obtain an electrochemical microcoil reactor. The firing temperature is preferably about 800 to 1200 ° C., but is not particularly limited and can be variously adjusted in consideration of the type of the cathode material and the like.

  The electrochemical microcoil reactor in which the anode tube with the electrolyte in which the solid electrolyte layer 1 is bonded to the outer surface of the anode tube 2 is formed into a coil shape by the above process, and then the cathode 3 is laminated on the outer side of the electrolyte layer. Obtainable.

  If necessary, the cathode or anode portion of the obtained electrochemical microcoil reactor can be machined to adjust the surface and adjust the dimensions. In the above manufacturing method, the case where the cathode is laminated after the porous tube with the electrolyte is prepared in advance by firing the tube coated with the electrolyte slurry has been described. After producing the body, it is also possible to coat the electrolyte slurry as appropriate, and the configuration thereof can be arbitrarily set.

  When these electrochemical microcoil reactors are stacked as a stack, as shown in FIG. 4, the coils are arranged in parallel, and a common fuel gas introduction and current collecting manifold is used for each coil structure. Can do. The manifold on the anode side can be used as an electrochemical reactor capable of multivolt power generation by being connected to a cathode current collector on the upper stage via an interconnect or the like.

  In addition, in the electrochemical microcoil reactor, when the stack is configured, the tubes to which the electrolyte layers are joined can be integrally joined by the cathode material, so that the outside of the tube, which has conventionally been difficult to connect, can be removed. Even in an oxidizing atmosphere, the tubes can be easily electrically connected without using expensive noble metal wires or the like.

The following effects are exhibited by the present invention.
(1) It consists of a new structure that can easily construct a cell stack by integration even if it is a microtube cell having a tube diameter of 2 mm or less, and can construct a structure that can sufficiently secure an air passage. An electrochemical microcoil reactor can be provided.
(2) An electrochemical reaction system such as a solid oxide fuel cell using the electrochemical microcoil reactor can be provided.
(3) Since the coil diameter can be arbitrarily changed, the air passage can be easily designed.
(4) The electrochemical reaction system of the present invention can be suitably used, for example, as a clean energy source or an environmental purification device.
(5) Even if the tube diameter is micronized, it is possible to easily pack the tubular cells.
(6) Since the process temperature in the manufacturing process of the microcoil tube can be lowered, it is possible to use an inexpensive cathode material, and reliably solve the problems of the conventional material in which a large amount of expensive cathode material is used. be able to.
(7) The electrolyte can be made thinner and the surface area per unit surface can be greatly increased, whereby the operating temperature can be lowered to about 400 to 650 ° C.

  EXAMPLES Next, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by the following Examples.

In this example, an electrochemical microcoil reactor was produced according to the following procedure. First, nitrocellulose as a binder and carbon powder as a pore-forming agent are added to a powder having a ZrO ₂ -10 mol% Y ₂ O ₃ composition (made by Tosoh Corporation), kneaded with water to form a clay, and then extruded. A tubular molded body was molded by a molding method. The tube diameter and tube thickness of the obtained tubular molded body were 1.5 mm and 0.4 mm, respectively (tube outer diameter 1.5 mm, tube inner diameter 0.7 mm).

Next, after opening the opening at one end of the obtained tubular molded body with vinyl acetate, the tube is immersed in a slurry containing a solid electrolyte having a composition of ZrO ₂ -10 mol% Y ₂ O ₃ to be electrolyte layer. The formation layer was dip-coated to obtain a tubular molded body with an electrolyte. Thereafter, the tubes were wound around each other on a roll having a diameter of 1 cm. At that time, the other end of the porous anode tube was exposed by 5 mm to form an exposed portion.

Next, this coil-shaped molded body was dried and then fired at 1450 ° C. for 2 hours to obtain an anode tube coil with electrolyte. Next, a paste containing LaSrCoFeO ₃ (manufactured by Nippon Ceramics Co., Ltd.) as a cathode material in the container was applied to the electrolyte layer surface, dried at 100 ° C., and then fired at 1000 ° C. for 1 hour. As a result, an electrochemical microcoil reactor was obtained.

  The embodiments of the present invention have been specifically described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. In the embodiment, only a single coil is shown. However, when a stack is constructed, it can be manufactured in the same procedure.

  As described above in detail, the present invention relates to an electrochemical microcoil reactor and an electrochemical reaction system composed thereof, and according to the configuration of the electrochemical microcoil reactor of the present invention, a coiled structure is formed by a tube. Since the body is manufactured, a structure that can be easily manufactured and handled even with a microtube having a tube diameter of 2 mm or less is obtained. In addition, since the coil diameter can be arbitrarily changed, the air passage can be easily designed. In addition, according to the above configuration, the cathode material can be stacked in a necessary amount on the electrolyte layer on the coil, so that the cathode material can be thinned and the surface area can be increased. Of an electrochemical reaction system such as a solid oxide fuel cell and the like using an electrochemical microcoil reactor excellent in cost performance and a solid oxide fuel cell that can be cooled to about 400 to 650 ° C. Is feasible. The present invention provides a new type of electrochemical microcoil reactor using a microcoil tube and a new technology and a new product relating to an electrochemical reaction system such as a solid oxide fuel cell using the electrochemical microcoil reactor. Useful as.

1 is a schematic view of an electrochemical microcoil reactor according to the present invention. It is a block diagram in the case of using the electrochemical microcoil reactor which concerns on this invention as SOFC single-piece | unit. It is an example of the manufacturing method of an electrochemical microcoil reactor. It is an example (packing example 1 and packing example 2) which constructed | assembled the electrochemical microcoil reactor which concerns on this invention as a stack.

Explanation of symbols

1 Electrolyte layer 2 Anode (exposed part)
3 Cathode 4 Tube hole (fuel gas passage)
5 Coil hole (air gas passage)
6 Fuel gas 7 Air gas 8a, 8b Fuel introduction pipes 9a, 9b Sealing material 10a, 10b Current collector wire 11 Current collector 12 Load 13 Anode material precursor 14 Electrolyte slurry 15 Cathode slurry 16 Microcoil type cell unit 17 Manifold

Claims (11)

  A structure in which a ceramic hollow tube is wound in a coil shape, an electrolyte layer (ion conductive phase) formed on the surface, and a cathode (air electrode) laminated on the electrolyte layer of the coil An electrochemical microcoil reactor characterized by that.   An oxide containing two or more elements selected from Zr, Ce, Mg, Sc, Ti, Al, Y, Ca, Gd, Sm, Ba, La, Sr, Ga, Bi, Nb, and W The electrochemical microcoil reactor of claim 1 which is a compound.   The hollow tube is composed of an electrolyte material and an element selected from Ni, Cu, Pt, Pd, Au, Ru, Co, La, Sr, and / or an oxide compound containing one or more of these elements. The electrochemical microcoil reactor according to claim 1.   The cathode (air electrode) material is composed of an element selected from Ag, La, Sr, Mn, Co, Fe, Sm, Ca, Ba, Ni, Mg and / or an oxide compound containing one or more of these elements. The electrochemical microcoil reactor of claim 1.   5. The electrochemical microcoil reactor according to claim 4, wherein the cathode material is a transition metal perovskite oxide or a composite of a transition metal perovskite oxide and a solid electrolyte material.   The electrochemical microcoil reactor of claim 1, wherein the electrolyte layer has a thickness of 1 to 100 microns.   The electrochemical microcoil reactor according to claim 1, wherein a tube diameter of the ceramic hollow tube is 2 mm or less.   The electrochemical microcoil reactor according to any one of claims 1 to 7, wherein the operating temperature can be lowered to 400 to 650 ° C.   An electrochemical reaction system for taking out an electric current by an electrochemical reaction, comprising the electrochemical microcoil reactor according to any one of claims 1 to 8 as a reactor.   The electrochemical reaction system according to claim 9, wherein units combining a plurality of electrochemical microcoil reactors are stacked.   The electrochemical reaction system according to claim 8 or 9, which is a solid oxide fuel cell, a hydrogen production reactor, or an exhaust gas purification reactor.