KR20060096700A - Prox reactor for fuel cell and fuel cell system having the same - Google Patents

Abstract

 A fuel cell system according to the present invention includes: a reformer including a carbon monoxide reducer for reducing the concentration of carbon monoxide contained in the reformed gas to generate hydrogen gas from a fuel containing hydrogen through a chemical catalytic reaction by thermal energy; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and oxygen; A fuel supply source for supplying fuel to the reformer; And an oxygen supply source for supplying oxygen to the generator, wherein the carbon monoxide reducer includes: a housing having an inlet and an outlet of the reformed gas at both ends thereof with a space therein; A reaction sheet disposed in an inner space of the housing such that a passage is formed along the flow direction of the reformed gas; And a catalyst layer formed by supporting a carbon monoxide selective oxidation catalyst on a surface of the reaction sheet.

 Fuel cell, reformer, housing, reaction sheet, metal thin film, passage, catalyst layer, porous, carbon monoxide reducer

Description

 Carbon monoxide reducer for fuel cell and fuel cell system having same {PROX REACTOR FOR FUEL CELL AND FUEL CELL SYSTEM HAVING THE SAME}

 1 is a schematic diagram showing the overall configuration of a fuel cell system according to an embodiment of the present invention.

2 is a perspective view illustrating a carbon monoxide reducer according to a first embodiment of the present invention.

3 is a cross-sectional view showing the structure of the carbon monoxide reducer according to the first embodiment of the present invention.

4 is a cross-sectional view showing a modification of the first embodiment of the present invention.

5 is a perspective view illustrating a carbon monoxide reducer according to a second embodiment of the present invention.

6 is a cross-sectional view illustrating a structure of a carbon monoxide reducer according to a second embodiment of the present invention.

7 is a cross-sectional view showing the structure of the carbon monoxide reducer according to the third embodiment of the present invention.

8 is a cross-sectional view showing the structure of the carbon monoxide reducer according to the fourth embodiment of the present invention.

 The present invention relates to a fuel cell system, and more particularly, to a fuel cell system having an improved structure of a carbon monoxide reducer for reducing the concentration of carbon monoxide in hydrogen gas generated from a reformer.

As is known, a fuel cell is a power generation system that converts chemical reaction energy of hydrogen and oxygen contained in hydrocarbon-based materials such as methanol, ethanol, and natural gas directly into electrical energy.

This fuel cell is classified into a phosphoric acid fuel cell, a molten carbonate fuel cell, a solid oxide fuel cell, a polymer electrolyte type or an alkaline fuel cell according to the type of electrolyte used. Each of these fuel cells operates on essentially the same principle, but differs in the type of fuel used, operating temperature, catalyst, and electrolyte.

Among these, the polymer electrolyte fuel cell (PEMFC, hereinafter called PEMFC for convenience), which has been developed recently, has superior output characteristics compared to other fuel cells, has a low operating temperature, fast start-up and response characteristics. In addition to mobile power supplies such as automobiles, as well as distributed power supplies such as homes and public buildings and small power supplies such as for electronic devices has a wide range of applications.

Such a PEMFC basically includes a stack, a reformer, a fuel tank, a fuel pump, and the like to constitute a system. The stack forms the housing of the fuel cell, and the fuel pump supplies the fuel in the fuel tank to the reformer. The reformer reforms the fuel to generate hydrogen gas and supplies the hydrogen gas to the stack. Thus, the PEMFC supplies fuel in the fuel tank to the reformer by operation of the fuel pump, reforming the fuel in the reformer to generate hydrogen gas, and electrochemically reacting the hydrogen gas and oxygen in the stack to generate electrical energy. Let's do it.

In the fuel cell system as described above, the reformer is a device for generating hydrogen gas from a fuel containing hydrogen through a chemical catalytic reaction by thermal energy. Typically, the reformer generates a thermal reactor and generates hydrogen gas from the fuel, and a water-gas shift (WGS) reaction of hydrogen gas generated from the reforming reaction unit or the hydrogen gas. A carbon monoxide reducer is provided to reduce the concentration of carbon monoxide contained in hydrogen gas through selective CO oxidation (PROX, hereinafter referred to as PROX reaction) of air.

The carbon monoxide reducer included in the conventional fuel cell system uses a PROX reaction to remove carbon monoxide from the reformed gas using a catalyst having high carbon monoxide selectivity after mixing air with the reformed gas.

In the carbon monoxide reducer, in order to improve the selectivity of the oxidation reaction and the reaction rate thereof, it is necessary to maintain the reaction part in a temperature range of about 130 to 250 ° C.

By the way, PROX reaction in a carbon monoxide reducer,

It is very difficult to keep the above temperature range because it is an exothermic reaction involving a large exotherm.

In addition, since a temperature difference tends to occur in the flow direction of the reformed gas, there is a problem in that it is difficult to maintain a uniform reaction temperature, and thus a constant oxidation reaction is difficult to occur.

In particular, when a hot spot occurs at a high temperature in the catalyst layer, the catalyst located at the hot spot suddenly decreases significantly in catalytic activity, and the hot spot moves to eventually destroy catalysts in the reactor.

As described above, the PROX reactor is a reactor in which temperature-sensitive reactions are performed, and since the performance decreases with the change of the temperature range, it is necessary to cool the reactor so as to suppress the temperature change and maintain the temperature within a certain range.

 Accordingly, the present invention has been made to solve the above-described problems, the fuel cell improved the structure of the carbon monoxide reducer so that the reaction temperature is maintained within the temperature range of the catalyst stable operation, to ensure sufficient catalyst performance The purpose is to provide a system.

In addition, an object of the present invention is to provide a fuel cell system having an improved structure of a carbon monoxide reducer so as to increase the surface area of the catalyst to improve the reaction rate.

 Carbon monoxide reducer used in the fuel cell system according to the present invention for achieving the above object, the housing having a space therein and the inlet and outlet of the reformed gas at both ends; A reaction sheet disposed in an inner space of the housing such that a passage is formed along the flow direction of the reformed gas; And a catalyst layer formed by supporting a carbon monoxide selective oxidation catalyst on a surface of the reaction sheet.

Carbon monoxide reducer used in the fuel cell system according to the present invention, it is preferable that the housing is made of a plate-shaped square case form. In this case, the reaction sheets may be stacked in at least two layers or more, and may be stacked at predetermined intervals so as to form passages between the reaction sheets to enable the flow of the reformed gas.

In this case, the housing may have a gas distribution hole formed at both intervals at which the reaction sheet is disposed at both ends of the inlet and the outlet, and the inlet and the outlet may communicate with the gas distribution hole. .

In addition, it is preferable that the carbon monoxide reducer used in the fuel cell system according to the present invention has a cylindrical shape. In this case, the reaction sheet is formed in a cylindrical shape so that the cross-sectional shape perpendicular to the longitudinal direction of the housing is circular, and the reaction sheet has at least two or more passages for allowing a flow of reformed gas between each reaction sheet. It may be stacked at predetermined intervals to be formed.

In addition, the carbon monoxide reducer used in the fuel cell system according to the present invention for achieving the above object, the housing having a space therein and the inlet and outlet of the reformed gas at both ends; It may be configured to include a catalyst structure for carbon monoxide selective oxidation disposed in the inner space of the housing to form a porous layer.

Here, the catalyst structure is a metal powder catalyst structure consisting of a carbon monoxide selective oxidation catalyst in the form of a metal powder is filled in the inner space of the housing to form a porous layer, or a porous member in which a carbon monoxide selective oxidation catalyst is coated on the porous member It is also possible to comprise a catalyst structure. In this case, the porous catalyst structure may be a resin foam (foam) is applied.

In addition, the fuel cell system according to the present invention for achieving the above object is provided with a carbon monoxide reducer for reducing the concentration of carbon monoxide contained in the reformed gas from the fuel containing hydrogen through a chemical catalytic reaction by thermal energy A reformer for generating hydrogen gas; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and oxygen; A fuel supply source for supplying fuel to the reformer; And an oxygen supply source for supplying oxygen to the generator, wherein the carbon monoxide reducer includes: a housing having an inlet and an outlet of the reformed gas at both ends thereof with a space therein; A reaction sheet disposed in an inner space of the housing such that a passage is formed along the flow direction of the reformed gas; And a catalyst layer formed by supporting a carbon monoxide selective oxidation catalyst on a surface of the reaction sheet.

In the fuel cell system according to the present invention, it is preferable that the housing is formed in a plate shape of a rectangular case shape, in which case the reaction sheet is provided with at least two layers or more, and the flow of reformed gas between each reaction sheet is provided. It can be stacked at predetermined intervals to allow passages to be formed.

In addition, in the fuel cell system according to the present invention, it is preferable that the housing is formed in a cylindrical shape. In this case, the reaction sheet has a cylindrical shape so that the cross-sectional shape perpendicular to the longitudinal direction of the housing is circular, and the reaction sheet has at least two or more passages for allowing a flow of reformed gas between each reaction sheet. Laminated at predetermined intervals as possible.

In addition, the fuel cell system according to the present invention for achieving the above object is provided with a carbon monoxide reducer for reducing the concentration of carbon monoxide contained in the reformed gas from the fuel containing hydrogen through a chemical catalytic reaction by thermal energy A reformer for generating hydrogen gas; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and oxygen; A fuel supply source for supplying fuel to the reformer; And an oxygen supply source for supplying oxygen to the generator, wherein the carbon monoxide reducer includes: a housing having an inlet and an outlet of the reformed gas at both ends thereof with a space therein; It may be configured to include a catalyst structure for carbon monoxide selective oxidation disposed in the inner space of the housing to form a porous layer.

Here, the catalyst structure is a metal powder catalyst structure consisting of a carbon monoxide selective oxidation catalyst in the form of a metal powder is filled in the inner space of the housing to form a porous layer, or a porous member in which a carbon monoxide selective oxidation catalyst is coated on the porous member It is also possible to comprise a catalyst structure. In this case, the porous catalyst structure may be a resin foam (foam) is applied.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 is a schematic diagram showing the overall configuration of a fuel cell system according to an embodiment of the present invention.

Referring to the drawings, the fuel cell system 100 according to the present invention reforms a fuel containing hydrogen to generate hydrogen gas, and polymer electrolyte fuel cell that generates electrical energy by reacting the hydrogen gas and oxygen (Polymer). Electrode Membrane Fuel Cell (PEMFC) is adopted.

In the fuel cell system 100, the fuel for generating electricity includes methanol, ethanol, natural gas, and the like. However, the fuel described below is defined as a fuel consisting of a liquid phase for convenience, and the liquid fuel and water are defined as a mixed fuel.

In addition, the system 100 may use pure oxygen gas stored in a separate storage means as oxygen reacting with the hydrogen, and may use air containing oxygen as it is. However, the latter example of using air as the oxygen fuel described above will be described below.

The fuel cell system 100 according to the present invention basically includes a stack 10 having at least one electricity generating unit 11 for generating electrical energy through an electrochemical reaction between hydrogen and oxygen, and as described above. A reformer 30 for generating hydrogen gas from the liquid fuel present and supplying the hydrogen gas to the electricity generating unit 11, a fuel supply source 50 for supplying the fuel to the reformer 30, and an oxygen reformer ( 30) and an oxygen supply source 70 for supplying the electricity generator 11, respectively.

The electricity generation unit 11 forms a stack of minimum units for generating electricity by arranging the separators 16 on both sides thereof with the electrode-electrolyte composite 12 at the center, and the electricity generation unit 11 is A plurality is provided to form the stack 10 of the laminated structure as in this embodiment. Here, the electrode-electrolyte composite 12 has an anode electrode and a cathode electrode at both sides, and functions to oxidize / reduce hydrogen and oxygen. The separator 16 functions as a conductor that forms a gas passage for supplying hydrogen gas and oxygen to both sides of the electrode-electrolyte composite 12 and connects the anode electrode and the cathode electrode in series.

As shown in the drawing, the outermost portion of the stack 10 may be in close contact plate 13 for contacting the plurality of electricity generating units 11 described above. However, the stack 10 according to the present invention excludes the adhesion plate 13 and the separator 16 positioned at the outermost side of the plurality of electricity generating units 11 may be configured to take the role of the adhesion plate. Can be. In addition to the function of bringing the adhesion plate 13 into close contact with the plurality of electricity generating units 11, the adhesion plate 13 may be configured to have a unique function of the separator 16.

In addition, the adhesion plate 13 includes a first injection unit 13a for supplying hydrogen gas generated from the reformer 30 to the electricity generation unit 11, and air supplied from an oxygen supply source (−). A second injection portion 13b for supplying to (11), a first discharge portion 13c for discharging hydrogen gas remaining after reacting at the anode electrode of the electrode-electrolyte composite 12, and electrode-electrolyte synthesis At the cathode electrode of the sieve 12, a second discharge portion 13d for discharging the unreacted air containing water generated by the reaction of hydrogen and oxygen is formed.

Meanwhile, the reformer 30 applied to the present invention includes a heat source unit 31 for generating heat energy through an oxidation catalyst reaction of a liquid fuel and air, and a mixture as described above through a steam reforming catalyst reaction by the heat energy. A reforming reaction unit 32 for generating hydrogen gas from the fuel, and at least one carbon monoxide reduction unit 33, 34 for reducing the concentration of carbon monoxide contained in the hydrogen gas. As an example, the carbon monoxide reducing units 33 and 34 may generate additional hydrogen gas through a water-gas shift (WGS) catalytic reaction and reduce the concentration of carbon monoxide contained in the hydrogen gas. It may include a conversion reaction unit 33, and PROX reaction unit 34 for reducing the concentration of carbon monoxide contained in the hydrogen gas through a catalytic reaction of hydrogen gas and air (Preferential CO Oxidation (PROX)), It is assumed that the carbon monoxide reducer of the present invention is the PROX reaction part 34 which reduces the concentration of carbon monoxide contained in hydrogen gas through a selective oxidation (PROX) catalyst reaction.

The fuel supply source 50 for supplying fuel to the reformer 30 as described above includes a first tank 51 for storing liquid fuel, a second tank 52 for storing water, and first and second, respectively. A fuel pump 53 connected to the tanks 51 and 52 is provided.

The oxygen source 70 includes an air pump 71 that sucks air with a predetermined pumping force and supplies the air to the reformer 30 and the electricity generator 11, respectively. At this time, the air pump 71 and the second injection portion 13b of the stack 10 may be connected by a supply line 99 in the form of a pipe.

In the drawings, reference numerals 91, 92, 93, 94, 95, 96, 97, and 98 denote connection lines in the form of pipes connecting the respective components.

The hydrogen gas generated through the reformer 30 and the oxygen in the air sucked through the air pump 71 are supplied to the electricity generator 11 when the fuel cell system 100 according to the present invention configured as described above is operated. In this case, the electricity generating unit 11 generates electricity, water, and heat through an electrochemical reaction between hydrogen and oxygen.

With reference to the accompanying drawings, each embodiment constituting the carbon monoxide reducer 34 that performs the PROX reaction in the fuel cell system 100 will be described in detail.

2 is a perspective view showing a carbon monoxide reducer according to a first embodiment of the present invention, Figure 3 is a cross-sectional view showing the structure of the carbon monoxide reducer according to the first embodiment of the present invention.

According to the first embodiment of the present invention, the carbon monoxide reducer 34 is disposed in the plate-shaped housing 35 having a rectangular case shape, and is disposed in the housing 35 through a selective oxidation catalytic reaction of the hydrogen gas and air. And reaction sheets 38 and 39 for reducing the concentration of carbon monoxide contained in the hydrogen gas.

The housing 35 has an internal space portion 35a of a predetermined volume, and has an inlet portion 36 for supplying the hydrogen gas and air to the space portion 35a, and the inlet portion 36 substantially. And an outlet portion 37 for discharging hydrogen gas generated by the selective oxidation catalytic reaction.

At this time, the inlet 36 and the reforming reaction unit 32 or the water gas conversion reaction unit 33 may be connected by a flow path in the form of a pipe. In addition, the inlet 36 and the air pump 71 of the oxygen source 70 (FIG. 1) may be connected to each other by the above-described flow path.

Preferably, the housing 35 forms an inlet 36 and an outlet 37 at positions corresponding to each other.

The reaction sheets 38 and 39 are catalyst modules for reducing the concentration of carbon monoxide contained in the hydrogen gas through the selective oxidation catalyst reaction of the hydrogen gas and air, and the carbon monoxide selective oxidation on the metal thin film 39a and its surface. It consists of the catalyst layer 39b formed by carrying a catalyst.

The reaction sheets 38 and 39 may be made of aluminum, and in addition, the reaction sheets 38 and 39 may be formed in the form of copper (Cu), nickel (Ni), zinc (Zn), iron (Fe), or a combination thereof.

In addition, the reaction sheets 38 and 39 are installed at predetermined intervals with the inlet 36 and the outlet 37 so that passages are formed along the flow direction of the hydrogen gas and air, and the housing 35 It is preferable to arrange | position parallel to the internal space part 35a of the lengthwise direction.

In addition, the reaction sheets 38 and 39 may be stacked on at least two layers. In this case, the reaction sheets 38 and 39 are stacked at predetermined intervals so as to form a passage between the reaction sheets 38 and 39 so as to allow the flow of the reformed gas. The reaction sheets 38 and 39 may be stacked on the inner surface of the housing 35. It is preferable to maximize the contact area between the catalyst layer 39b, the hydrogen gas and air by installing them slightly apart.

As shown in FIG. 3, the first embodiment of the present invention comprises two reaction sheets 38 and 39, but the carbon monoxide reducer 34 of the present invention is not limited thereto. By constructing the reaction area can be widened and the reaction rate can be improved.

In the carbon monoxide reducer 34 according to the first embodiment of the present invention, the flat reaction sheets 38 and 39 that cause the oxidation catalyst reaction are laminated at regular intervals in the space part 35a of the housing 35. In addition, the flow distribution of the hydrogen gas and the air flowing in from the inlet 36 is uniform, and a plurality of passages through which the hydrogen gas and the air pass are formed to form a contact area between the fuel and the air on the surface of the catalyst layer 39b. By increasing the reaction rate can be improved.

In addition, the space 35a in the housing 35 allows the heat generated during the PROX reaction to be cooled by air cooling.

Therefore, the temperature difference in the flow direction of the reformed gas can be minimized to maintain a uniform reaction temperature to maintain the temperature of the reaction portion in a certain range, and in particular, to prevent the occurrence of high temperature hot spots in the catalyst layer. To ensure sufficient catalytic performance.

On the other hand, Figure 4 is a modified example of the first embodiment according to the present invention, when the reaction sheet (438, 439) is laminated more than two, all the reaction sheet is laminated with hydrogen gas and air flowing through the inlet (436) The gas distribution holes 431 and 432 are formed at intervals at which the reaction sheets 438 and 439 are disposed at both ends of the housing 435 so as to pass evenly in contact with the surfaces of the 438 and 439.

In this case, the inlet portion 436 and the outlet portion 437 may be provided separately from the housing 435, and are installed at both ends of the housing 435, as shown in the figure, the gas distribution holes (431,432) It is installed in communication with.

As an example, the inlet part 436 and the outlet part 437 are provided with an inlet port 436a and an outlet port 437a for inflow and outflow of hydrogen gas and air, and the gas on the surface contacting the opposite housing 435. Communication holes 433 and 434 communicating with the distribution holes 431 and 432 are formed.

In the modified example of the first embodiment of the present invention, the hydrogen gas and the air introduced through the inlet 436a of the inlet 436 react through the communication holes 433 and 434 and the gas distribution holes 431 and 432, respectively. Since the reaction parts are evenly contacted with the surfaces of the sheets 438 and 439, the flow of hydrogen gas and air is uniform, and the reaction can be made more stable.

As a second embodiment of the present invention, as shown in Figures 5 and 6, the housing 135 has a cylindrical structure in the form of a pipeline having an internal space of a predetermined volume, and the inlet portion 136 and The outflow part 137 is formed.

In addition, reaction sheets 138 and 139 are disposed in the housing 135 to reduce the concentration of carbon monoxide contained in the hydrogen gas through a selective oxidation catalytic reaction of the hydrogen gas and air.

The reaction sheets 138 and 139 are catalyst modules for reducing the concentration of carbon monoxide contained in the hydrogen gas through a selective oxidation catalyst reaction of the hydrogen gas and air, and a metal thin film and a carbon monoxide selective oxidation catalyst are supported on the surface thereof. It is composed of a catalyst layer to be formed, such a configuration is the same as the first embodiment of the first detailed description thereof will be omitted.

The reaction sheets 138 and 139 may be made of aluminum, and in addition, the reaction sheets 138 and 139 may be formed in the form of copper (Cu), nickel (Ni), zinc (Zn), iron (Fe), or a combination thereof.

In addition, the reaction sheets 138 and 139 may have a cylindrical shape such that a cross-sectional shape perpendicular to the longitudinal direction of the housing 135 is circular so that passages are formed along the flow direction of the hydrogen gas and air.

In addition, the reaction sheets 138 and 139 may be provided in at least two or more layers. In this case, the reaction sheets 138 and 139 may be formed such that a passage through which the reformed gas flows is formed between the respective reaction sheets 138 and 139. It is preferable to maximize the contact area between the catalyst layer and the hydrogen gas and air by being installed in layers at intervals and slightly apart from the inner surface of the housing 135.

In the second embodiment of the present invention, as in the first embodiment, the cylindrical reaction sheets 138 and 139, which cause oxidation-catalyzed reactions, are stacked in a spaced portion in the housing 135 at predetermined intervals. In addition, the flow of hydrogen gas and air introduced from the inlet 136 is uniform, and a plurality of passages through which hydrogen gas and air pass are formed to increase the contact area of fuel and air to the surface of the catalyst layer to react. Can improve speed.

In addition, the space in the housing 135 allows the heat generated during the PROX reaction to be cooled by air cooling.

Therefore, the temperature difference in the flow direction of the reformed gas can be minimized to maintain a uniform reaction temperature to maintain the temperature of the reaction portion in a certain range, and in particular, to prevent the occurrence of high temperature hot spots in the catalyst layer. To ensure sufficient catalytic performance.

In addition, the present invention proposes a carbon monoxide reducer configured by disposing a catalyst structure for carbon monoxide selective oxidation to form a porous layer in the inner space of the housing so as to increase the reaction area of the catalyst to improve the reactivity and the reaction rate.

7 is a cross-sectional view illustrating a structure of a carbon monoxide reducer according to a third embodiment of the present invention. The third embodiment of the present invention has a space portion therein and an inflow portion 236 and an outlet of reformed gas at both ends thereof. It comprises a housing 235 is provided with a portion 237, and a metal powder catalyst structure 238 is filled in the inner space of the housing 235 to form a porous layer.

The catalyst structure 238 is a carbon monoxide selective oxidation catalyst, and is filled in the inner space of the housing 235 in the form of metal powder.

The metal powder catalyst structure 238 forms a porous layer inside the housing 235. Accordingly, the reformed gas introduced through the inlet 236 causes a reaction while passing through the porous layer between the catalyst structures 238 and exits to the outlet 237.

Since the third embodiment of the present invention has a wider reaction area due to the porous layer due to the catalyst structure 238, the reactivity is improved when the fuel passes through the carbon monoxide reducer 234, and the reaction rate is increased. It is greatly improved.

8 is a cross-sectional view illustrating a structure of a carbon monoxide reducer according to a fourth embodiment of the present invention. The fourth embodiment of the present invention has a space portion therein and an inflow portion of reformed gas at both ends 336. And a housing 335 having an outlet portion 337, and a porous catalyst structure 338 disposed in an inner space of the housing 335 and coated with a carbon monoxide selective oxidation catalyst.

The porous catalyst structure 338 is a carbon monoxide selective oxidation catalyst is coated on a porous member such as a sponge (sponge), it is preferable that a resin foam (foam) is used as an example.

The porous catalyst structure 338 in the form as described above serves as a passage through which a number of pores of the foam allows the flow of the reforming gas, and the catalyst and the surface of each of the pores and the entire surface are coated with the catalyst so that By increasing the contact area, the reaction rate may be greatly improved when hydrogen gas and air pass through the porous catalyst structure 338.

As such, when the porous catalyst structure 338 having a foam form is provided inside the housing 335, a porous layer is formed inside the housing 335 due to the porous catalyst structure 338. Therefore, the reformed gas introduced through the inlet 336 causes a reaction while passing through the hole of the porous catalyst structure 338, and exits to the outlet 337.

In the fourth embodiment of the present invention, the reaction area becomes wider when the fuel passes through the carbon monoxide reducer 334 due to the porous catalyst structure 338, so that the reactivity is improved, and the reaction rate is greatly improved. will be.

Referring to the operation of the fuel cell system according to an embodiment of the present invention configured as described above in detail as follows.

First, the fuel pump 53 is operated to supply the liquid fuel stored in the first tank 51 to the heat source part 31 through the supply line 91. At the same time, the air pump 71 is operated to supply air to the heat source portion 31. The liquid fuel and air then generate heat of reaction at a predetermined temperature. At this time, the combustion gas of the liquid fuel and air generated by the oxidation catalyst reaction is supplied to the reforming reaction unit 32 through the supply line 93 together with the reaction heat.

Subsequently, the liquid fuel stored in the first tank 51 and the water stored in the second tank 52 are supplied to the reforming reaction unit 32 through the supply line 94 by driving the fuel pump 53. . Then, the reforming reaction unit 32 generates hydrogen gas from the mixed fuel through the reforming reaction of the fuel while the mixed fuel absorbs heat of reaction. In other words, the reforming reaction unit 32 generates a hydrogen gas containing carbon dioxide and hydrogen through a decomposition reaction of the fuel through a steam reforming catalytic reaction. At this time, the reforming reaction unit 32 generates hydrogen gas containing a trace amount of carbon monoxide as a minor product.

Next, the hydrogen gas containing a trace amount of carbon monoxide is supplied into the water gas conversion reaction unit 33 through the supply line 95. Here, hydrogen is further generated through a water gas shift reaction of hydrogen gas, and the concentration of carbon monoxide contained in the hydrogen gas is primarily reduced.

Subsequently, the hydrogen gas is supplied into the carbon monoxide reducer 34 through the supply line 96. At the same time, air is supplied to the carbon monoxide reducer 34 through the supply line 97 by driving the air pump 71. Here, the concentration of carbon monoxide contained in the hydrogen gas is secondarily reduced through the selective oxidation of hydrogen gas and air.

At this time, the carbon monoxide reducer 34 according to the embodiment of the present invention effectively cools the heat generated when reducing the concentration of carbon monoxide contained in the hydrogen gas by air cooling, thereby improving the selectivity of the oxidation reaction and its reaction rate. .

In addition, since the reaction area becomes wider due to the porous layer, the reactivity is improved when the fuel passes the carbon monoxide reducer 34, and the reaction rate is greatly improved.

Next, the hydrogen gas is supplied to the first injection unit 13a of the stack 10 through the supply line 98, and air is supplied through the supply line 99 by driving the air pump 71. It supplies to the 2nd injection part 13b of 10).

Thus, the hydrogen gas is supplied to the anode electrode of the electrode-electrolyte composite 12 through the separator 16. Air is then supplied to the cathode of the electrode-electrolyte composite 12 through the separator 16.

As a result, the anode decomposes hydrogen gas into electrons and protons (hydrogen ions) through an oxidation reaction. The proton moves to the cathode electrode through the electrolyte membrane, and the electrons do not move through the electrolyte membrane, but move to the cathode electrode of the neighboring electrode-electrolyte composite 12 through the separator 16. And concomitantly generates heat and water.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it is within the scope of the present invention.

 According to the fuel cell system according to the present invention, due to the space in the housing of the carbon monoxide reducer, it is possible to cool the heat generated during the PROX reaction by air cooling so that the reaction temperature is maintained within the temperature range in which the catalyst operates stably, There is an effect that can secure the catalytic performance.

In addition, the surface area of the catalyst can be widened to improve the reaction speed, and the reaction efficiency of the overall carbon monoxide reducer can be improved.

In addition, the structure of the reaction unit of the carbon monoxide reducer is simple and easy to manufacture, there is an effect that can reduce the manufacturing cost to secure a relative competitive advantage.

Claims (20)

 A housing having a space therein and having an inlet and an outlet of the reformed gas at both ends thereof; A reaction sheet disposed in an inner space of the housing such that a passage is formed along the flow direction of the reformed gas; And A catalyst layer formed by supporting a carbon monoxide selective oxidation catalyst on a surface of the reaction sheet; Carbon monoxide reducer for fuel cells comprising a.  The method of claim 1, The housing is a carbon monoxide reducer for a fuel cell, characterized in that the plate-shaped in the form of a square case.  The method of claim 2, The reaction sheet is laminated at least two or more layers, the carbon monoxide reducer for a fuel cell are laminated at a predetermined interval so as to form a passage allowing a flow of the reforming gas between each reaction sheet.  The method of claim 3, The housing is provided with gas distribution holes at intervals at which the reaction sheet is disposed at both ends of the inlet and outlet, The inlet and outlet portion is a carbon monoxide reducer for a fuel cell, characterized in that the communication hole is formed in communication with the gas distribution hole.  The method of claim 1, The housing is a cylindrical shape, the reaction sheet is a carbon monoxide reducer for a fuel cell, characterized in that the cylindrical shape so that the cross-sectional shape perpendicular to the longitudinal direction of the housing is circular.  The method of claim 5, The reaction sheet is provided with at least two layers, the carbon monoxide reducer for a fuel cell is provided at predetermined intervals so as to form a passage between the reaction sheet to enable the flow of the reformed gas. A housing having a space therein and having an inlet and an outlet of the reformed gas at both ends thereof; A catalyst structure for carbon monoxide selective oxidation disposed in the inner space of the housing and forming a porous layer; Carbon monoxide reducer for fuel cells comprising a. The carbon monoxide catalyst according to claim 7, wherein the catalyst structure is a metal powder type catalyst structure in which a carbon monoxide selective oxidation catalyst is formed in the form of a metal powder, and is filled in an inner space of the housing to form a porous layer. Reducer. 8. The carbon monoxide reducer for fuel cells according to claim 7, wherein the catalyst structure is a porous catalyst structure in which a carbon monoxide selective oxidation catalyst is coated on the porous member. 10. The carbon monoxide reducer for fuel cells according to claim 9, wherein the porous catalyst structure is a resin foam.  A reformer having a carbon monoxide reducer for reducing the concentration of carbon monoxide contained in the reformed gas to generate hydrogen gas from a fuel containing hydrogen through a chemical catalytic reaction by thermal energy; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and oxygen; A fuel supply source for supplying fuel to the reformer; And An oxygen supply source for supplying oxygen to the generator, The carbon monoxide reducer, A housing having a space therein and having an inlet and an outlet of the reformed gas at both ends thereof; A reaction sheet disposed in an inner space of the housing such that a passage is formed along the flow direction of the reformed gas; And A catalyst layer formed by supporting a carbon monoxide selective oxidation catalyst on a surface of the reaction sheet; Fuel cell system configured to include. The method of claim 11, The housing is a fuel cell system, characterized in that consisting of a plate-shaped square case.  The method of claim 12,  The reaction sheet is stacked on at least two layers or more, and the fuel cell system is laminated at predetermined intervals so as to form a passage between the reaction sheet to enable the flow of the reformed gas. The method of claim 13, The housing is provided with gas distribution holes at intervals at which the reaction sheet is disposed at both ends of the inlet and outlet, The inlet and the outlet are fuel cell system, characterized in that the communication hole is formed in communication with the gas distribution hole. The method of claim 11, The housing is a cylindrical shape, the reaction sheet is a carbon monoxide reducer for a fuel cell, characterized in that the cylindrical shape so that the cross-sectional shape perpendicular to the longitudinal direction of the housing is circular. The method of claim 15, The reaction sheet is provided with at least two layers, the fuel cell system is provided at a predetermined interval so that the passage for allowing the flow of the reforming gas is formed between each reaction sheet.  A reformer having a carbon monoxide reducer for reducing the concentration of carbon monoxide contained in the reformed gas to generate hydrogen gas from a fuel containing hydrogen through a chemical catalytic reaction by thermal energy; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and oxygen; A fuel supply source for supplying fuel to the reformer; And An oxygen supply source for supplying oxygen to the generator, The carbon monoxide reducer, A housing having a space therein and having an inlet and an outlet of the reformed gas at both ends thereof; A catalyst structure for carbon monoxide selective oxidation disposed in the inner space of the housing and forming a porous layer; Fuel cell system configured to include.  18. The fuel cell system as claimed in claim 17, wherein the catalyst structure is a metal powder type catalyst structure in which a carbon monoxide selective oxidation catalyst is in the form of a metal powder, and is filled in an inner space of the housing to form a porous layer. .  The fuel cell system as claimed in claim 17, wherein the catalyst structure is a porous catalyst structure in which a carbon monoxide selective oxidation catalyst is coated on a porous member.  20. The fuel cell system of claim 19, wherein the porous catalyst structure is a resin foam.

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