KR20060112276A - Micro reforming apparatus for fuel cell - Google Patents

Abstract

A small-sized reformer for a fuel cell is provided to integrally mount a platinum membrane and a palladium membrane into a casing member. Pores(32) with the micro unit are formed to the inside of a porous reforming member(30). A gas reforming catalyst(34) with single matter or mixture matter is coated on the surface of pores. When the heated methanol gas is passed through the pores as the natural vapor type, the catalyst reaction is maximized as compared with the existing reforming member because the surface area of the catalyst reaction is increased as compared with the existing current path structure. The output density according to the hydrogen reforming is enhanced.

Description

Micro Reforming Apparatus for Fuel Cell

1 shows a fuel cell of a conventional power generation unit and a reformer,

(a) is a perspective view showing a power generation unit and a reformer

(b) is a perspective view of main parts showing a reformer.

Figure 2 is a partially cut perspective view showing a micro reformer for a fuel cell according to the present invention.

3 is a structural diagram of FIG. 2;

Figure 4 is a structural diagram showing another embodiment of a micro reformer for a fuel cell of the present invention.

Figure 5 is a structural diagram showing another embodiment of the ultra-compact reformer for a fuel cell of the present invention.

6 is a structural diagram showing another embodiment of the present invention in which the reformer of FIG.

Figure 7 is a schematic diagram showing the pore forming step of the porous reforming means in the micro-modifier for the fuel cell of the present invention.

Explanation of symbols on the main parts of the drawings

1 .... Subminiature reformer 10 .... Casing member

12 .... fuel supply 14 .... heating means

30 .... Porous reforming means 32 .... Internal pores of the reforming means

34 .. Gas reforming catalyst 50 .... Carbon monoxide (CO) removal catalyst means

70 .... Hydrogen Selection Permeation

The present invention relates to a reforming apparatus for supplying hydrogen gas to a fuel cell, in particular, a polymer electrolyte fuel cell (PEMFC) fuel cell, and more specifically, to purify high purity hydrogen and supply it to a fuel cell (power generation unit). This improves the efficiency of the overall fuel cell and at the same time effectively removes carbon monoxide (hereinafter referred to as 'CO'), which is the poisoning cause of the catalyst. Therefore, the present invention relates to a fuel cell ultra-compact reformer that can simplify the structure of the reformer and can be easily mounted in a small portable device.

With the depletion of modern energy and environmental problems, the development of fuel cells with high energy efficiency and low environmental pollution has been intensively developed. Such fuel cells can directly oxidize fuel such as hydrogen to generate electricity. It generates an environmentally friendly advantage that the noise is very low during operation and little contaminants are generated.

In addition, a fuel cell is defined as a cell (cell) having the capability of producing direct current by converting chemical energy of fuel (hydrogen) directly into electrical energy. Unlike conventional cells, fuel cells continuously supply fuel and air from outside. There is a difference in producing electricity.

In other words, the basic concept of a fuel cell is the use of electrons generated by the reaction of hydrogen and oxygen, for example, hydrogen passes through the anode and oxygen passes through the cathode, where hydrogen is electrochemically Reacts with oxygen to generate water while generating current at the electrode.

On the other hand, since the direct current is generated while electrons pass through the electrolyte (membrane), heat is additionally produced, and the direct current is used as the power of the direct current motor or converted into the alternating current by the inverter, and is generated in the fuel cell. The heat can be used to generate steam for reforming or heat for cooling and heating, which is also useful in terms of heat recycling compared to conventional lithium ion batteries.

In addition, the fuel of the fuel cell uses hydrogen generated through a reforming process using pure hydrogen, hydrocarbons such as methanol, and the like. An apparatus used for such reforming is a reforming apparatus according to the present invention.

In addition, the oxygen supplied to the fuel cell makes it possible to increase the efficiency of the fuel cell as it is pure oxygen, but since it involves various problems due to the actual oxygen storage, the oxygen-rich air is directly used. The reaction of

Anode: H _2- > 2H + + 2e-,

Cathode: O ₂ + 2H + + 2e--> H ₂ O

Overall: H ₂ + O _2- > H ₂ O + Current + Heat

At this time, the electrolyte (electrode), which is an electron transfer medium interposed between the anode and the cathode, serves to enable the transfer of hydrogen ions from one electrode to the other electrode. Most preferably, both electrodes (anode / cathode) are provided as thin as possible in order not to contact each other in order to minimize the resistance of the transmission.

Meanwhile, the fuel cells described so far can be classified into various forms as shown in Tables 1 and 2 below. Basically, the operating principle of the fuel cells is not significantly different, and only differences in fuel type, operating temperature, catalyst and electrolyte, etc. There is.

At this time, the various types of fuel cells described in Tables 1 and 2 below are Phosphoric Acid Fuel Cell (PAFC), Alkaline Fuel Cell (AFC), and Polymer Electrolyte Fuel Cell (Proton). Exchange Membrane Fuel Cell (PEMFC), Molten Carbonate Fuel Cell (MCFC), Solid Oxide Fuel Cell (SOFC), and Direct Methanol Fuel Cell (DMFC) and the like, and when describing the fuel cells by type in the following abbreviated.

Classification of fuel cell by electrolyte, catalyst and operating temperature Kinds Ex harm catalyst Driving temperature PAFC Phosphoric Acid (Liquid) platinum on PTFE / carbon 200 ℃ AFC Potassium Hydroxide (Liquid) platinum on carbon 80 ℃ PEMFC Nafion Dow Polymer platinum on carbon  85-100 ℃ MCFC Lithium or potassium carbonate (liquid) Nickel nickel compounds 650 ℃ SOFC Yttria-stabilized zirconia (solid) Nickel Zirconia cermet 1000 ℃ DMFC Polymer Membrane Pt-Ru Pt / C 25-130 ℃

Classification of fuel cells by main fuel  Kinds Power generation temperature Electrolyte Main fuel Technology level Applicable object PEMFC DMFC Room temperature-100 ℃ Ion (H +) conductive polymer membrane Hydrogen methanol Development and demonstration stage Small power car PAFC  150-200 ℃ Phosphoric Acid (H3PO4) Natural Gas Methanol  Commercialization stage Distributed power MCFC 600-700 ℃ Molten Carbonate (Li2CO3-K2CO3) Natural Gas Coal Gas Development stage Combined Cycle Cogeneration SOFC 700-1000 ℃ Solid Oxides Yttria-stabilized zirconia Natural Gas Coal Gas Development stage Combined Cycle Cogeneration AFC Room temperature-100 ℃ Hydrogen in use Special purpose

Meanwhile, among the various types of fuel cells, the use of mobile communication terminals, laptops, or portable multi-computers (hereinafter referred to as 'portable devices') is rapidly increasing. have.

By the way, portable devices such as laptops and mobile phones, as well as improving functions and services, in particular, the main concern is the miniaturization of the device, the miniaturization of fuel cells used in the portable device is a major concern of the research and development.

For example, although the performance of secondary batteries such as lithium ion batteries, which have been conventionally used, has been greatly improved compared to when they were initially installed in portable devices, research into the mounting of fuel cells with high capacity and miniaturization has been concentrated. It is becoming.

On the other hand, among the various types of fuel cells described above, the most widely researched and practical applications of small (micro) fuel cells mounted on portable devices are DMFC and PEMFC (PEFC).

In this case, DMFC and PEMFC use methanol and hydrogen as fuels, respectively, and accordingly, the performance and fuel supply system of the fuel cell are different from each other, and have advantages and disadvantages.

However, since DMFC is significantly lower than PEMFC in terms of output density, it is being researched for power supply of portable devices, but its actual utilization value is decreasing.

On the other hand, since PEMFC (PEFC) uses hydrogen as a fuel, it is necessary to use a reformer for reforming fuel such as methanol to hydrogen gas and supplying it to a fuel cell (power generation unit). Except for the power density, it is known to be advantageous for power supply of portable devices.

Therefore, in the case of a fuel cell for a portable device, particularly a PEMFC, miniaturization of a reformer and a reduction in the mounting (mounting) area of the actual device are a prerequisite.

For example, the fuel cell, especially a reformer used in a portable device, unlike a car or household fuel cell that can secure a certain amount of space, the miniaturization is very important factor.

Meanwhile, FIG. 1 schematically illustrates a reformer used in an electronic calculator among conventional portable devices.

That is, as shown in FIG. 1A, a reformer 120 for supplying the power generation unit 110 and the reformed hydrogen of the fuel cell 100 to the power generation unit 110 is known.

However, as illustrated in FIGS. 1A and 1B, the conventional reformer 120 for a fuel cell is not a separate structure diagram or code, but a structure in which cells formed with narrow channels (channels) are stacked in multiple layers. Since the amount of hydrogen gas to be reformed is insignificant and the overall size of the hydrogen gas is miniaturized, there are many problems in the manufacturing process, such as forming a flow path in the actual cell because the structure of the multilayer cells.

For example, the conventional reformer 120 forms a narrow micro flow path through a fine process on a substrate (cell) such as silicon (Si), glass, or stainless steel, and uses a catalyst to narrow the flow path. Coating on the phase allows the generation of modified hydrogen gas.

In addition, the conventional reformer 120 stacks a silicon wafer or the like, and integrates a catalytic combustor, an evaporator, a hydrogen generator, a CO remover, a sensor, a heater for heating, and the like necessary for reforming (generating) hydrogen therein.

In the conventional reformer 120, a thin film heater using gold (Au) is provided inside the reformer to make a high temperature part up to 280 ° C. or more to perform 'catalytic combustion' requiring high temperature treatment. Actually very complex structure (system) that performs each process of 'CO removal', 'reforming fuel evaporation' and 'combustion fuel evaporation' by passing fuel sequentially through the flow path (pass line) formed on the stacked substrates according to the temperature. to be.

In addition, the reformer is difficult to insulate the high temperature while generating a severe deviation depending on the temperature gradient height and the amount of hydrogen coming out is difficult in actual commercialization.

On the other hand, the conventional multi-layer cell stack and flow path-type small reformer similar to the reformer 120 of FIG. 1 is disclosed in detail in US Patent Application Publication US2004 / 019591. I have the same problem.

Accordingly, a micro reformer capable of miniaturizing the reformer and generating high-purity hydrogen gas has also been required. When the catalyst is coated on the surface of the pores of the porous ceramic, the effective implementation of water quality and the miniaturization of the reformer are required. It would be desirable to be able to facilitate.

The present invention is to solve the above-mentioned conventional problems, and to improve the removal efficiency of the CO which causes catalyst poisoning of the fuel cell while finally being able to purify the high-purity hydrogen to supply to the fuel cell (power generation unit) It is a first object to provide a micro reformer for a fuel cell which improves the fuel cell output density.

In addition, a porous reforming means coated with a hydrophobic catalyst layer on the surface of the inner pores, each of the catalyst removal means (membrane) and hydrogen selective transmission means (membrane) for CO removal is integrated into the casing member, thereby minimizing the overall structure of the reformer. It is a second object to provide a very small reformer for a fuel cell, which is particularly suitable for use in a portable device while enabling high purity hydrogen generation by enabling to be implemented.

As a technical aspect for achieving the above object, the present invention, the fuel supply port, and at least one heating means for heating the fuel supplied through each of which is provided, at least one side casing member; And,

Porous reforming means embedded in the casing member, the surface of the pores formed therein is coated with a catalyst for reforming gas to reform the fuel gas into hydrogen gas;

It provides a micro reformer for a fuel cell configured to include.

At this time, it is preferable to further include a catalyst means for removing CO deposited on the porous reforming means.

It is also possible to further include a hydrogen selective permeation means which is stacked on the porous reforming means or CO removal catalyst means and discharges high purity hydrogen.

The casing member may be made of a ceramic having excellent heat insulating properties, the fuel supply port may be provided at a bottom side of the ceramic casing member, and the heating means may be provided as a heater coil embedded in both bottom sides of the ceramic casing member. have.

In addition, the porous reforming means, when burning the ceramic tape made by mixing the ceramic powder and the organic material is incinerated to remove the organic material contained in the ceramic to form pores in the ceramic integrally, after the ceramic tape formed with the pores are laminated Sintered to form an integral porous ceramic.

In addition, the gas reforming catalyst coated on the surfaces of the internal pores of the porous reforming means may be composed of a mixed catalyst of copper (Cu) and zinc oxide (ZnO).

In this case, it is preferable that one of Ga ₂ O ₃ , Al ₂ O ₃ , ZrO ₂ and Cr ₂ O ₃ is further mixed with the gas reforming catalyst.

In addition, the porous reforming means, the gas reforming layer is coated with a mixed catalyst of copper (Cu) and zinc oxide (ZnO) for reforming the heated methanol gas to hydrogen gas to the surface of the internal pores to provide a gas reforming region, It is also preferable that the platinum catalyst provided on the gas reforming layer to remove CO contained in the gas is coated in a double catalyst layer structure including a CO removal layer coated on a surface of internal pores to provide a CO removal region.

In this case, one of Ga ₂ O ₃ , Al ₂ O ₃ , ZrO ₂ and Cr ₂ O ₃ may be further mixed with the mixed catalyst of the gas reforming layer and the platinum catalyst of the CO removing layer.

In the gas reforming means of the double catalyst layer structure, a porous ceramic having pores formed therein is immersed in a mixed catalyst solution to a predetermined depth, and the remaining portion is immersed in a platinum catalyst solution so that a double catalyst layer is coated on the pore surface. .

In this case, the porous reforming means may be embedded in the casing member in a sealed state by the CO removal catalyst means or the hydrogen selective permeation means stacked thereon.

In addition, the porous reforming means of the double catalyst layer structure may be embedded in the casing member in a sealed state by the CO removal catalyst means or the hydrogen selective permeation means stacked thereon.

At this time, the CO removal layer of the porous reforming means of the double catalyst layer structure is preferably configured to be in contact with the air to protrude above the opening of the casing member to increase the CO removal efficiency.

The catalyst means for removing CO may be provided as a platinum membrane for removing CO.

In addition, the hydrogen-selective permeation means may be provided as a palladium (Pd) membrane that enables the purge of high purity hydrogen.

At this time, the fuel inlet and the heating means are disposed in the center of the casing member having both sides opened, and both sides of the porous reforming means coated on the inner pores with a single catalyst for gas reforming or a double catalyst for gas reforming and CO removal. It is also preferable that the catalyst means for CO removal and the hydrogen selective permeation means are each configured in a double hydrogen discharge form embedded in the casing member.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, the ultra-small reformer for a fuel cell of the present invention minimizes the complicated process generated in the existing reformer, and in particular, it is possible to generate a large amount of high-purity hydrogen gas, while excellent in the CO removal effect that causes catalyst poisoning, hydrogen gas This greatly improves the power density of the fuel cell itself.

On the other hand, as described above, the micro reformer for a fuel cell of the present invention is a reformer used in PEMFC (see Table 2) using hydrogen (gas) as a main fuel among various types of fuel cells.

Next, FIG. 2 and FIG. 3 show an embodiment of the micro reformer 1 for a fuel cell according to the present invention.

That is, the micro reformer 1 of the embodiment of the present invention is largely divided into a casing member 10 and a porous reforming means 30 for reforming methanol gas, which is substantially a fuel gas, with hydrogen gas, and further removing CO. It may be configured to include one or both of the catalyst means 50, the hydrogen permeation means 70 for generating high purity hydrogen.

In this case, the CO removal catalyst means 50 and the hydrogen selective permeation means 70 are provided on the porous reforming means 30, respectively, or if all of them are provided, the CO removal catalyst means 50 and It is preferable that the hydrogen selective transmission means 70 are sequentially provided on the porous reforming means 30.

Hereinafter, the present invention will be described in detail with reference to the constituent means (10) (30) (50) 70 in the micro reformer (1).

First, in the first micro reformer 1 of the present invention, the casing member 10 constitutes a mold of the reformer. As shown in FIGS. 2 and 3, at least one fuel supply port 12 and the The fuel supplied through the fuel supply port 12 is provided with the heating means 14 for heating methanol, for example, and one side is opened.

That is, in the reformer of the present invention, the casing member 10 may be provided in the shape of a rectangular box having an upper opening. The casing member 10 may have a circular or polygonal shape depending on the shape of a portable device in which a fuel cell is mounted. It will not be difficult to change the design to, as described in the present embodiment provided only in the rectangular box shape.

At this time, the casing member 10 of the present invention is most preferably made of a material having excellent heat insulating properties, for example, ceramic, the casing member 10 of such a ceramic is of a predetermined thickness manufactured in a suitable form. It may be provided through a tape casting (or slip casting) process in which ceramic tapes are laminated, sintered and integrated.

Therefore, the casing member 10 of the present invention, which is a ceramic, has high heat resistance due to the characteristics of the ceramic, and thus provides a heat insulating effect that prevents heat generated from the inside by the heating means 14 from being transferred to the outside of the casing member. It is easy.

In this case, at least one fuel supply port 12 of the ceramic casing member 10 may be provided at one point or at both sides of the ceramic casing member 10.

On the other hand, the casing member 10 of the present invention shown in Figures 2 and 3 is preferably adjusted in size in consideration of the overall height of the reformer 1 is produced about 1-2cm.

On the other hand, the heating means 14, as shown in Figures 2 and 3, may be provided as a heater coil embedded in both sides of the bottom of the ceramic casing member (10).

At this time, the heating means 14 heats methanol, which is a fuel, to be produced as a gas, and the methanol gas is reformed into hydrogen gas while passing through the porous reforming means 30 described in detail below.

Next, FIGS. 2 and 3 show a porous reforming means 30 which enables substantial reforming in the ultra compact reformer 1 of the first embodiment of the present invention.

That is, as shown in Figures 2 and 3, the porous reforming means 30 of the present invention is embedded in the upper side of the heating means 14 into the inner space of the casing member 10, the pores formed therein ( The surfaces of the 32 are coated with a gas reforming catalyst 34 so that the fuel gas passing therethrough is reformed into hydrogen gas.

In this case, the porous reforming means 30 embedded in the casing member 10 can be manufactured through a known process, for example, a tape casting or slip casting process, similarly to the casing member, How to form the pores 32 will be described in detail in the following FIG.

Therefore, the porous reforming means 30 of the present invention is formed therein micropores 32 of a few microns to a few hundred microns in size, porous ceramic (porous ceramic that is excellent in insulation properties and easy to manufacture composite).

At this time, as shown in Figures 2 and 3, the porous reforming means 30 can be produced in consideration of the overall height of the reformer to 1-2cm, the reformer 1 of the present invention as a whole is a porous reforming Since the means 30 are not used and the cell stack structure provided with the flow paths as in the past, mounting on a portable device facilitates a suitable miniaturization.

On the other hand, on the surface of the pores 32 formed in a myriad of micro units in the porous reforming means 30, which is the porous ceramic of the present invention, a catalyst 34 for gas reforming or mixed material described in detail below is Coated.

Therefore, the porous reforming means 30 of the present invention is a catalyst 34 coated on the surface of the myriad of pores therein, when the heated methanol gas passes through the pores 32 in a natural evaporation form, Since the surface area of the catalytic reaction is increased as compared to the flow path structure, it is possible to maximize the catalytic reaction as compared to the conventional reformer, and thus improve the output density due to hydrogen reforming.

In addition, it is possible to reform the hydrogen gas of the fuel gas by a natural evaporation phenomenon of gas evaporation without the need for externally supplied pressure, such as a conventional reformer.

On the other hand, a method of forming in the ceramic a myriad of pores 32 formed in the interior of the porous reforming means 30 of the ceramic is shown in FIG.

That is, as shown in FIG. 7, a binder such as a ceramic powder (S) and an organic material (O), for example, a methacrylate solution (MEK) or a methacrylate emulsion (Methacrylate emulsion) dissolved in MEK. (Binder) by mixing the organic material to make a ceramic tape by a known tape casting method (burning) at a temperature of approximately 500 ℃, the organic material (O) mixed with the ceramic is burned and removed to remove the organic material In the space, the pores 32 are entangled with each other and are provided in a myriad of gas flow paths.

Then, the ceramic tapes having the pores 32 formed thereon are stacked in a desired shape as shown in FIG. 7 and sintered at a high temperature of 1100 ° C. to finally form a porous ceramic having numerous micro pores 32 formed therein. Modification means 30 may be provided.

In addition, the gas reforming catalyst 34 coated on the surfaces of the internal pores 32 of the porous reforming means 30 substantially reforms the methanol gas into hydrogen gas, and includes copper (Cu) and zinc oxide (ZnO). It is known to provide a mixed catalyst and such a copper and zinc oxide to modify the methanol gas with hydrogen.

On the other hand, the mixing ratio of copper and zinc oxide of the gas reforming mixed catalyst may be approximately 44:11 on a mass basis.

Meanwhile, in order to maintain a stable catalytic function for a long time when catalyzing methanol gas through copper and zinc oxide, it is known that the ionic state of Cu + 1 must be well maintained. The zinc oxide (ZnO) is Cu + It is known to stabilize the ionic state of 1.

In addition, the mixed catalyst 34 of copper and zinc oxide has Ga ₂ O ₃ and Al ₂ O, which are known to maintain Cu + 1 ions to maintain high activity and selectivity of a stable catalyst for a long time while stabilizing thermal characteristics. _3, ZrO ₂ and Cr ₂ O together is preferable to addition of a ₃ add a metal oxide of, in the present embodiment utilizes the normal use of alumina (Al ₂ O _3).

In this case, the mixing ratio of copper (Cu), zinc oxide (ZnO), and alumina (Al ₂ O ₃ ) may be approximately 44: 11: 100 on a mass basis, but is not necessarily limited thereto.

Accordingly, in the micro reformer 1 of the present invention, the porous reforming means 30 for reforming the fuel gas into hydrogen gas by the catalytic reaction is provided as a porous ceramic having a myriad of pores 32 formed therein. Since the mixed catalyst 34 for smoothing the hydrogen gas material is coated on the surfaces of the pores, it is possible to miniaturize the device and to generate higher purity hydrogen gas than the reformer having a complicated structure constituting the existing flow path. do.

On the other hand, such a porous ceramic reforming means 30 also provides other advantages, for example, because the fuel of the methanol supplied to the inside of the casing member 10 absorbs in the form of a capillary tube, the supplied fuel is the casing member ( 10) to prevent leakage to the outside.

At this time, the method of coating the catalyst on the surface of the pores of the porous reforming means 30, the porous ceramic is formed by a method such as tape casting and the pores 32 formed therein through combustion and sintering by forming a nano-synthesis method The mixed catalyst may be coated on the surface of the pores 32 in the porous ceramic by immersion in a Cu / ZnO / Al ₂ O ₃ bath.

Next, as shown in Figures 2 and 3, in the micro-reformer (1) according to the present invention, the catalyst means (50) for stacking the top of the porous reforming means (30) to remove CO, and the catalyst means ( Hydrogen selective transmission means 70 stacked on top of 50 and discharging high purity hydrogen may be provided through a thin film deposition method such as a sputter process.

At this time, the catalyst means for CO removal 50 is composed of a platinum (Pt) membrane (membrane), such platinum is known to provide a function to absorb and remove the CO contained in the gas, CO is the fuel cell At least 100 ppm should be included in the gas because it causes poisoning of the catalyst which is an important component.

Next, the hydrogen-selective permeation means 70 may be provided substantially as a palladium (Pd) membrane (membrane), such that the palladium 70 selectively permeates hydrogen to enable higher purity hydrogen purification. It is known.

In this case, as described above, the catalyst for removing the CO 50 and the hydrogen permeation means 70 are each provided on the porous reforming means 30 or all of them may be provided in sequence, in this case CO The removal catalyst means 50 and the hydrogen selective permeation means 70 may be sequentially stacked to provide higher purity hydrogen from which CO is removed.

Next, FIG. 4 shows another embodiment of the micro reformer for a fuel cell of the present invention.

That is, as shown in Figure 4, in the micro-reformer (1) of another embodiment of the present invention, the porous reforming means (30), which implements substantial hydrophobic material, reforms the heated methanol gas with hydrogen gas (Cu). And a catalyst (34a) of zinc oxide (ZnO) mixed with a gas reforming layer (30a) coated on the surfaces of the pores 32 therein, and a platinum (Pt) catalyst for removing CO contained in the gas prior to the catalytic means ( 34b) is transformed into the structure of the double catalyst layer by the CO removal layer 30b coated on the surface of the inner pores 32 coated.

At this time, the mixed catalyst 34a and the platinum catalyst 34b of the gas reforming layer 30a and the CO removal layer 30b are formed on the surface of the internal pores of the integrated porous ceramic reforming means 30. By coating sequentially in the direction, the inner pores 32 of the reforming means do not have a difference between layers.

For example, as shown in FIG. 4, the gas reforming layer 30a of the porous reforming means 30 is formed to a total height of 2/3 of the porous reforming means 30, which is a porous ceramic, and the remaining 1/3. The part can be formed by the CO removal layer 30b.

Alternatively, the gas reforming layer 30a may be formed to 4-5 mm, and the CO removal layer 30b may be formed to about 0.5-1 mm.

That is, it is possible to improve the catalyst layer structure of the gas reforming means 30 to remove CO while focusing on gas reforming.

At this time, as shown in Figure 5, the mixed catalyst 34a of copper (Cu) and zinc oxide (ZnO) coated on the surface of the internal pores 32 of the gas reforming layer (30a) of the porous reforming means (30) As described above, Ga ₂ O ₃ , Al ₂ O ₃ , ZrO ₂ and Cr ₂ are known to maintain the ionic state of Cu + 1 to stabilize the thermal properties and maintain high activity and selectivity of the catalyst for a long time. It is preferable to add together one metal oxide of O ₃ or the like.

In addition, the platinum catalyst 34b coated on the surfaces of the pores 32 of the CO removal layer 30b maintains the ion state of Pt + 1 for stabilizing thermal properties and maintaining high activity and selectivity of the stable catalyst for a long time. Metal oxides such as Ga ₂ O ₃ , Al ₂ O ₃ , ZrO _2, and Cr ₂ O ₃ , which are known to be added, are preferably added together. In this embodiment, alumina (Al ₂ O ₃ ) that is commonly used is used.

Therefore, in the micro reformer 1 of another embodiment of the present invention, the fuel gas is coated by separately coating catalysts having different properties, that is, gas reforming and CO removal, on the surfaces of the internal pores of the porous reforming means 30. The catalytic reaction is reformed into hydrogen gas, and at the same time, CO, which causes catalyst poisoning, is more reliably removed along with the upper platinum membrane 50.

As a result, the ultra-compact reformer of the present invention makes it possible to supply the generated hydrogen gas to the fuel cell (power generation unit) with purified hydrogen gas from which CO is further removed.

At this time, the porous surface coating method of the porous ceramic of the mixed catalyst 34a and the platinum catalyst 34b, as described above, is formed by forming the integral porous ceramic, which is the gas reforming means 30, by a mixed catalyst, that is, a nano synthesis method. Partial immersion in a Cu / ZnO / Al ₂ O ₃ bath coats the mixed catalyst on the surface of the pores 32.

Next, a platinum catalyst is coated on the surface of the pores 32 by immersing the remaining portion of the porous ceramic not immersed in the mixed catalyst solution in a Pt / Al ₂ O ₃ bath formed by nano synthesis.

On the other hand, as shown in Figures 3 and 4, in the embodiments of the micro-modifier of the present invention, the porous reforming means 30 is built into the casing member 10 and does not come into contact with the outside of the casing member. It may be provided in a sealed state.

In this case, heat will not be released to the outside to maintain thermal insulation.

Next, FIG. 5 shows another embodiment of the present invention, the micro-modifier, the CO removal layer (30b) coated with a platinum catalyst on the surface of the internal pores of the porous reforming means 30 is the casing member (10) It can protrude out of and make contact with the atmosphere.

In this case, oxygen in the atmosphere is brought into contact with the CO removal layer 30b, and this oxygen further improves the CO removal efficiency, thereby greatly reducing the amount of CO included in the discharge gas (hydrogen gas).

At this time, the internal pores of the porous ceramic, which is the porous reforming means 30, are actually micro-sized, and the gas reforming means 30 is reformed to hydrogen gas while the heated methanol gas is naturally evaporated. Although the CO removal layer 30b of the phosphorous porous ceramic is exposed to the atmosphere, air is further introduced by the atmospheric pressure, and since hydrogen gas passing through the gas reforming layer 30a is hardly discharged into the atmosphere, hydrogen is removed. There is little concern about leakage of gas.

Therefore, as shown in FIG. 5, since the micro reformer 1 of another embodiment of the present invention includes a porous reforming means 30 having a double catalyst layer structure, gas reforming as well as perfect removal of CO can be achieved. Implementation will ultimately improve the fuel cell's efficiency.

Next, Fig. 6 shows another embodiment of the micro reformer for a fuel cell of the present invention.

That is, as shown in FIG. 6, another micro reformer 1 of the present invention is disposed in the center of the casing member 10 in which the fuel inlet 12 and the heating means 14 are open at both sides, At the same time, on the basis of this, on both sides of the casing member 10, the porous catalyst 30 and the single catalyst 34 of FIG. 3 or the double catalysts 34a and 34b of FIGS. 4 and 5 are coated on the surfaces of the pores. The catalyst means 50 and the hydrogen selective permeation means 70 may each be composed of a double hydrogen discharge structure embedded in the casing member.

Accordingly, the micro reformer 1 of the present invention according to another embodiment reforms the fuel at both inner sides of one casing member 10, and releases high-purity hydrogen in double which selectively permeates hydrogen while removing CO. The structure allows the hydrogen fuel to be supplied to two fuel cells (power generation units) as one reformer, which makes it possible to be mounted in equipment using multiple fuel cells and to reduce the number of reformers. It is useful for miniaturization of fuel cells mounted in equipment.

According to the micro reformer for a fuel cell of the present invention, by using a reforming means of porous ceramics, the catalytic reaction surface area is increased during reforming after fuel gas generation to enable high purity hydrogen purification.

That is, the gas reforming catalyst or the CO removal catalyst is coated on the surface of the myriad micro pores formed inside the reforming means, which is a porous ceramic, so that the coating area of the catalyst is greatly enlarged compared to the flat flow path, and thus the catalytic reaction area. By increasing the efficiency of the process, the reforming efficiency of the water can be increased, thereby providing the advantage of maximizing the cell efficiency of the PEMFC which finally uses hydrogen as a fuel while enabling high purity tank purification.

In addition, the porous reforming means, which is a hydrogen reforming portion, the catalyst means of the platinum membrane, which is a CO removal portion (PROX), and the palladium membrane, which is an optional hydrogen permeation means, are integrally manufactured and manufactured in the casing member, thereby stacking cells having a conventional complex flow path. Compared to the reformer of the structure, the structure is more simplified to allow the miniaturization, which has another effect of improving the mountability of the portable device.

In addition, since it has a capillary function for absorbing the supplied methanol fuel provided by the porous ceramic as the porous reforming means as the hydrogen reforming portion, the fuel does not leak to the outside of the casing member, thereby enabling sufficient gasification and water quality during heating. To provide other excellent effects.

Finally, by enclosing the porous reforming means, the catalytic means, and the hydrogen selective permeation means with the ceramic casing member, the thermal insulation affecting the hydrogen reforming is maintained, and the difference in temperature gradient according to the height of the reformer is reduced. Another excellent effect is to provide.

While the invention has been shown and described with respect to specific embodiments thereof, those skilled in the art can variously modify the invention without departing from the spirit and scope of the invention as set forth in the claims below. And that it can be changed. Nevertheless, it will be clearly understood that all such modifications and variations are included within the scope of the present invention.

Claims (16)

A casing member having at least one fuel supply port and at least one heating means for heating the fuel supplied through the fuel supply port, and having at least one side opened; And, Porous reforming means embedded in the casing member, the surface of the pores formed therein is coated with a catalyst for reforming gas to reform the fuel gas into hydrogen gas; Miniature reformer for a fuel cell comprising a. The method of claim 1, Micro reformer further comprises a catalyst means for removing CO deposited on the porous reforming means. The method according to claim 1 or 2, And a hydrogen selective permeation means which is stacked on the porous reforming means or the CO removal catalyst means and discharges hydrogen of high purity. The method of claim 1, The casing member is composed of a ceramic having excellent heat insulating properties, the fuel supply port is provided on the bottom side of the ceramic casing member, the heating means is a very small, characterized in that the heater coil embedded in the bottom side of the ceramic casing member Reformer. The method of claim 1, In the porous reforming means, when the ceramic tape and the organic material are mixed with each other, the organic material contained in the ceramic tape is incinerated and the pores are integrally formed in the ceramic, and the ceramic tapes having the pores are laminated and sintered. Micro reformer, characterized in that composed of a single porous ceramic. The method of claim 1, The gas reforming catalyst coated on the surface of the internal pores of the porous reforming means is a micro reformer, characterized in that consisting of a mixed catalyst of copper (Cu) and zinc oxide (ZnO). The method of claim 6, The gas reforming catalyst is a compact reformer, characterized in that one of Ga ₂ O ₃ , Al ₂ O ₃ , ZrO ₂ and Cr ₂ O ₃ is further mixed. The method of claim 1, The porous reforming means, A gas reforming layer coated with a mixed catalyst of copper (Cu) and zinc oxide (ZnO) for reforming the heated methanol gas with hydrogen gas to provide a gas reforming region by coating the surface of the inner pores; A CO removal layer provided on the gas reforming layer and coated with a surface of internal pores with a platinum catalyst for removing CO included in the gas to provide a CO removal region; Micro reformer comprising a double catalyst layer structure, including. The method of claim 8, The micro reformer, characterized in that the mixed catalyst of the gas reforming layer and the platinum catalyst of the CO removal layer further comprises one of Ga ₂ O ₃ , Al ₂ O ₃ , ZrO ₂ and Cr ₂ O ₃ . The method of claim 8, The gas reforming means of the double catalyst layer structure is characterized in that the porous ceramic having pores formed therein is immersed in the mixed catalyst solution to a predetermined depth, and the remaining portion is immersed in the platinum catalyst solution so that the double catalyst layer is coated on the pore surface. Micro reformer. The method of claim 1, The porous reformer is a micro-modifier, characterized in that the built-in sealed state in the casing member by the CO removal catalyst means or hydrogen selective transmission means stacked on the top. The method of claim 8, The micro reformer of the dual catalyst layer structure is characterized in that the micro reformer is built in a sealed state inside the casing member by a catalyst removal means for hydrogen or a hydrogen selective transmission means stacked on top. The method of claim 8, The micro-reformer of the porous catalyst means of the dual catalyst layer structure is characterized in that the small reformer is projected to the upper portion of the opening of the casing member to increase the CO removal efficiency is configured to enable air contact. The method according to any one of claims 2, 11 and 12, The catalytic reforming means for CO removal, micro reformer characterized in that provided as a platinum membrane for removing CO. The method according to any one of claims 3, 11, and 12, Wherein said hydrogen selective permeation means is provided as a palladium (Pd) membrane that enables refined discharge of high purity hydrogen. The method of claim 1, The fuel injection port and the heating means are disposed at the center of the casing member having both sides opened, and both the reforming means and the CO reforming are coated on the inner pores with a single catalyst for gas reforming or a double catalyst for gas reforming and CO removal. A micro reformer characterized in that the catalyst means for hydrogen and the hydrogen selective transmission means are each composed of a double hydrogen discharge form embedded in the casing member.

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