KR100804693B1 - Carbon monoxide reducing device for reformer used in fuel cell, and fuel cell system comprising same - Google Patents

Abstract

A device for reducing carbon monoxide for a fuel cell modifier, and a fuel cell system containing the device are provided to improve carbon monoxide oxidation activity and selectivity and to simplify structure. A device for reducing carbon monoxide comprises a first reactor which is provided with a first carbon monoxide oxidation catalyst reacting with the carbon monoxide of a reformed fuel; and a second reactor which is provided with a second carbon monoxide oxidation catalyst reacting with the carbon monoxide of a reformed fuel, wherein the carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst and is supplied to the second reactor to react with the second carbon monoxide oxidation catalyst, and the first carbon monoxide oxidation catalyst has a higher selectivity of oxidation of carbon monoxide than the second carbon monoxide oxidation catalyst.

Description

Carbon monoxide reduction device of reformer for fuel cell and fuel cell system including same {CARBON MONOXIDE REDUCING DEVICE FOR REFORMER USED IN FUEL CELL, AND FUEL CELL SYSTEM COMPRISING SAME}

1 is a view schematically showing the structure of a fuel cell system of the present invention.

2 is a perspective view of a carbon monoxide reduction device according to an embodiment of the present invention.

3 is a block diagram schematically showing the carbon monoxide reduction device of FIG.

4 is a graph showing a temperature change with time during a heating process when preparing a first carbon monoxide oxidation catalyst according to an embodiment of the present invention.

5 is a view showing the concentration of carbon monoxide discharged at the carbon monoxide reduction device outlet according to the temperature inside the second reactor measured in Example 1 of the present invention.

6 is a graph showing the hydrogen gas residual ratio measured in Example 1 and Comparative Examples 1 and 2. FIG.

[Industrial use]

The present invention relates to a carbon monoxide reduction device for a fuel cell reformer and a fuel cell system including the same, and more particularly, to a carbon monoxide reduction device for a fuel cell reformer having a simple structure and excellent in carbon monoxide oxidation activity and selectivity, and a fuel comprising the same. It relates to a battery system.

[Prior art]

A fuel cell is a power generation system that directly converts the chemical reaction energy of hydrogen and oxidant contained in hydrocarbon-based materials such as methanol, ethanol, and natural gas into electrical energy. Such a fuel cell is a clean energy source that can replace fossil energy, and has a merit of outputting a wide range of outputs by stacking unit cells, and having an energy density of 4 to 10 times compared to a small lithium battery. It is attracting attention as a compact and mobile portable power source.

Representative examples of the fuel cell include a polymer electrolyte fuel cell (PEMFC) and a direct oxidation fuel cell (Direct Oxidation Fuel Cell). When methanol is used as a fuel in the direct oxidation fuel cell, it is called a direct methanol fuel cell (DMFC).

The polymer electrolyte fuel cell has an advantage of having a high energy density and a high output, but requires attention to handling hydrogen gas and reforms fuel for reforming methane, methanol, natural gas, etc. to produce hydrogen as fuel gas. There is a problem that requires additional equipment such as a device.

In such a fuel cell system, the stack that substantially generates electricity is comprised of a number of unit cells consisting of a membrane-electrode assembly (MEA) and a separator (also called a bipolar plate). It has a stacked structure of several tens. The membrane-electrode assembly has a structure in which an anode electrode and a cathode electrode are positioned with a polymer electrolyte membrane including a hydrogen ion conductive polymer interposed therebetween.

The principle of generating electricity in a fuel cell is that fuel is supplied to an anode electrode, which is a fuel electrode, adsorbed to a catalyst of the anode electrode, and the fuel is oxidized to generate hydrogen ions and electrons. Reaching the cathode electrode, hydrogen ions pass through the polymer electrolyte membrane and are delivered to the cathode electrode. An oxidant is supplied to the cathode, and the oxidant, hydrogen ions, and electrons react on the catalyst of the cathode to generate electricity while producing water.

The fuel cell system includes a stack, a reformer, a fuel tank, a fuel pump, and the like. The stack forms the body 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.

In a typical fuel cell system, the reformer includes a reforming reaction unit generating hydrogen gas from the fuel through a reforming catalytic reaction by thermal energy, and a concentration of carbon monoxide contained in the hydrogen gas through an oxidation reaction between the hydrogen gas and the oxidant. It consists of a carbon monoxide reduction unit to reduce the. Since the reaction of the carbon monoxide reduction unit is a reaction using a carbon monoxide oxidation catalyst, studies for increasing the activity and selectivity of the carbon monoxide oxidation catalyst have been conducted.

An object of the present invention is to provide a carbon monoxide reduction device for a fuel cell reformer having a simple structure and excellent in carbon monoxide oxidation activity and selectivity.

Still another object of the present invention is to provide a fuel cell system including the carbon monoxide reduction device.

In order to achieve the above object, the present invention comprises a first reactor having a first carbon monoxide oxidation catalyst for the oxidation catalytic reaction with carbon monoxide; And a second reactor having a second carbon monoxide oxidation catalyst for performing an oxidation catalytic reaction with carbon monoxide, wherein the carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst, and then supplied to the second reactor. An apparatus for reducing carbon monoxide in a fuel cell reformer that reacts with a carbon monoxide oxidation catalyst.

The present invention also the temperature inside the first reactor is reduced to the second carbon monoxide oxidation catalyst reaction temperature according to the flow direction of the reforming fuel, the temperature inside the second reactor is maintained at the second carbon monoxide oxidation catalyst reaction temperature An apparatus for reducing carbon monoxide in a phosphorus fuel cell reformer is provided.

The present invention also includes a reforming reaction unit for generating hydrogen gas from fuel through a reforming catalytic reaction by thermal energy, and a reformer including the carbon monoxide reduction device; At least one electricity generating unit generating electrical energy through an electrochemical reaction between hydrogen gas and an oxidant; A fuel supply unit supplying the fuel to the reforming reaction unit; And an oxidant supply unit supplying an oxidant to the electricity generation unit.

Hereinafter, the present invention will be described in more detail.

An apparatus for reducing carbon monoxide in a reformer for a fuel cell of the present invention includes a first reactor having a first carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in a reformed fuel; And a second reactor having a second carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in the reformed fuel, wherein the carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst and then to the second reactor. To react with a second carbon monoxide oxidation catalyst to provide a carbon monoxide reduction device for a fuel cell reformer.

In the carbon monoxide reduction device, a selective oxidation (PROX) process of carbon monoxide occurs. The selective oxidation process is a process for reducing the content of carbon monoxide contained in impurities in the final product in ppm units. Since carbon monoxide poisons the catalyst of the fuel cell, it is a factor that drastically degrades the electrode performance, so the content of carbon monoxide must be reduced. do.

In this selective oxidation process, platinum-based catalysts (Pt, Rh, Ru, etc.) supported on alumina have been conventionally used, but the platinum-based catalysts have low selectivity at high temperature, and optimal reaction of the platinum-based catalysts with carbon monoxide There is a problem that a heat exchanger is required to maintain the temperature 110 to 130 ℃.

Accordingly, in the present invention, the carbon monoxide abatement apparatus includes a first reactor and a second reactor, and the first reactor includes a first carbon monoxide oxidation catalyst having good selectivity for carbon monoxide oxidation and having catalytic activity even at a wide temperature range. In the second reactor, the second carbon monoxide oxidation catalyst having good activity of the carbon monoxide oxidation reaction is provided.

In addition, the temperature inside the first reactor is gradually reduced to the second carbon monoxide oxidation catalyst reaction temperature in accordance with the flow direction of the reforming fuel, the temperature inside the second reactor is maintained at the second carbon monoxide oxidation catalyst reaction temperature.

The temperature inside the first reactor may be reduced through a heat exchanger according to the flow direction of the reformed fuel, or may be reduced through natural heat exchange between the first reactor and the vicinity of the first reactor without a heat exchanger. Therefore, there is no need for a separate heat exchanger or a heater or cooler for maintaining the inside of the first reactor at a constant temperature, and the carbon monoxide reduction device of the present invention has a simple structure. When reducing the temperature inside the first reactor without a heat exchanger, various methods can be used. The feed flow rate of the reformed fuel and the amount of the first carbon monoxide oxidation catalyst are fixed, and the material at the first reactor outlet can be lowered by using a material having excellent thermal conductivity as the material of the first reactor. However, the method of reducing the temperature inside the first reactor without the heat exchanger is not limited thereto.

In addition, since the temperature at the first reactor outlet becomes the reaction temperature of the second carbon monoxide oxidation catalyst, much heating or cooling is not required to reach the second carbon monoxide oxidation catalyst reaction temperature at the second reactor inlet, thereby reducing the carbon monoxide reduction apparatus of the present invention. The thermal efficiency is improved.

The first reactor has a first inlet for supplying carbon monoxide at one end, and a first outlet for discharging carbon monoxide at the other end, and the second reactor has a second inlet for supplying carbon monoxide at one end. And a second outlet for discharging carbon monoxide at the other end, and the first outlet of the first reactor and the second inlet of the second reactor are preferably connected to each other.

The carbon monoxide reduction device of the present invention may have a U-shape, wherein the one U-shaped pillar has a first carbon monoxide oxidation catalyst, and the other U-shaped pillar has a second carbon monoxide oxidation catalyst. desirable.

In addition, the first reactor and the second reactor may be installed in one housing.

As long as the first carbon monoxide oxidation catalyst is a catalyst having good selectivity of the carbon monoxide oxidation reaction, any one can be used, but CeO ₂ , and CuO preferably include an active material including CuO, where CeO ₂ , MO (where M is a transition Metal), and an active material comprising CuO. This is because the first carbon monoxide oxidation catalyst has good selectivity of the carbon monoxide oxidation reaction and has activity of the carbon monoxide oxidation reaction in a wide temperature range.

The M is preferably an element selected from the group consisting of Ni, Co, Fe, Sn, Pb, Se, and combinations thereof, and more preferably M is Ni.

The CeO _2, and the first carbon monoxide oxidizing catalyst containing CuO is a CeO _2, and CuO in the weight ratio 15 to 25: it is preferred to include from 1 to 10 weight ratio. When the weight ratio of CeO ₂ and CuO is less than the lower limit of the weight ratio, desired catalytic activity cannot be obtained, and when the weight ratio exceeds the upper limit of the weight ratio, the activity of the catalyst is rather deteriorated, which is not preferable.

The first carbon monoxide oxidation catalyst including CeO ₂ , MO (where M is a transition metal) and CuO, preferably contains CeO ₂ , MO and CuO in a weight ratio of 15 to 25: 0.1 to 0.4: 1 to 10 by weight. Do. When the weight ratio of CeO ₂ , MO and CuO is less than the lower limit of the weight ratio, desired catalytic activity cannot be obtained, and when the weight ratio exceeds the upper limit of the weight ratio, the activity of the catalyst is rather deteriorated, which is not preferable.

In the first carbon monoxide oxidation catalyst, the active material is preferably supported on a carrier selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and a combination thereof, and more preferably supported on Al ₂ O ₃ . Do.

The first carbon monoxide oxidation catalyst comprising CeO ₂ , and an active material comprising CuO, and the first carbon monoxide oxidation catalyst comprising an active material comprising CeO ₂ , MO (where M is a transition metal) and CuO It may be prepared in the same manner.

When the first carbon monoxide oxidation catalyst including the active material including CeO ₂ and CuO is prepared, the precursor is dissolved in an aqueous solution containing Cu to prepare a mixed solution. When preparing a first carbon monoxide oxidation catalyst including an active material including CeO ₂ , MO, and CuO, Ce precursors and M precursors are dissolved in an aqueous solution containing Cu to prepare a mixed solution. At this time, when the carbon monoxide oxidation catalyst according to the present invention is to be supported on a carrier, a carrier is added to the mixed solution. The mixed solution is heated with agitation while giving a temperature change, followed by drying to obtain a compound. When the compound is calcined, the carbon monoxide oxidation catalyst of the present invention can be prepared.

The temperature change of the heating process is preferably made at 200 to 500 ℃. One embodiment of the temperature change is shown in FIG. 4. Referring to Figure 4, the heating is carried out in three stages, the first stage is heated to 200 ℃, the second stage is heated to 300 ℃, the third stage is heated to 550 ℃ for 2 hours.

As the Ce precursor, Ce nitrate, ammonium Ce nitrate, Ce acetate, Ce chloride, or a mixture thereof is preferably used, and Ce (NO ₃ ) ₃ .6H ₂ O, (NH ₄ ) ₂ Ce ( More preferably, NO ₃ ) ₆ is used. In addition, the cerium compound may also be used in the form of a hydrate.

As the M precursor, M nitrate, M acetate, or M chloride may be used, and representative examples thereof include Ni nitrate, Co nitrate, Fe nitrate, Ni (NO ₃ ) ₂ , and Ni (OCOCH ₃ ) ₂ , NiCl _2, Co (NO ₃₎ may be mentioned _{2, Fe (NO 3) 3} . In addition, the M precursor may be used in the form of a hydrate, of course.

The aqueous solution containing Cu may be prepared by dissolving the Cu precursor in water. Cu nitrate and Cu acetate may be used as the Cu precursor, and representative examples thereof include Cu (NO ₃ ) ₂ , Cu (NO ₃ ) ₂ , Cu (NO ₃ ) ₂ , or Cu (OCOCH ₃ ). have. Of course, the Cu precursor may be used in the form of a hydrate.

The carrier is preferably at least one selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and combinations thereof, and more preferably Al ₂ O ₃ .

It is preferable to perform the said calcination process in the temperature range of 450-550 degreeC. If the temperature is less than 450 ℃, calcination is not completely done, the porous structure of the first carbon monoxide oxidation catalyst may be damaged. The calcination step is preferably carried out for 1 to 2 hours.

The second carbon monoxide oxidation catalyst can be used as long as the catalyst having excellent activity for the carbon monoxide oxidation reaction, but preferably includes an active material containing a Pt-based metal.

The Pt-based metal is preferably at least one selected from the group consisting of Pt, Rh, Ru, and a combination thereof, and more preferably Pt.

In addition, the second carbon monoxide oxidation catalyst, the active material is graphite, denka black, Ketjen black, acetylene black, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanoballs, activated carbon, alumina, silica, zirconia, titania It is preferred that it is supported on at least one carrier selected from the group consisting of, and combinations thereof.

When the second carbon monoxide oxidation catalyst is a platinum-based catalyst, the temperature of the reformed fuel discharged from the first reactor or the reformed fuel at the second reactor inlet is preferably 110 to 130 ° C. When platinum-based catalysts are used as carbon monoxide oxidation catalysts, carbon monoxide conversion is known to be the largest at 110 to 130 ° C. Therefore, it is preferable that the temperature of the reformed fuel discharged from the first reactor or the reformed fuel at the second reactor inlet is 110 to 130 ° C.

In addition, the present invention is a reforming reaction unit for generating hydrogen gas from the fuel through the reforming catalytic reaction by the thermal energy, a reformer including the carbon monoxide reduction device; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and an oxidant; A fuel supply unit supplying the fuel to the reforming reaction unit; And an oxidant supply unit supplying an oxidant to the electricity generation unit.

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.

Hereinafter, the fuel cell system will be described in detail with reference to FIG. 1.

As shown in FIG. 1, the fuel cell system 100 generates hydrogen gas from a stack 10 having an electricity generating unit 11 for generating electrical energy through an electrochemical reaction, and liquid fuel. A reformer 30 for supplying the hydrogen gas to the electricity generator 11, a fuel supply unit 50 for supplying the fuel to the reformer 30, and an oxidant for the reformer 30 and the electricity generation. It is comprised including the oxidant supply part 70 which supplies each to the part 11 ,.

The electricity generating unit forms the stack of the smallest unit for generating electricity by arranging the separators 16 on both sides thereof with the membrane-electrode assembly 12 at the center thereof, and the plurality of electricity generating units 11 are provided. The stack 10 of the laminated structure as in the embodiment is formed. The membrane-electrode assembly 12 includes an anode electrode and a cathode electrode at both sides, and functions to oxidize and reduce hydrogen and an oxidant. In addition, the separator 16 functions as a conductor that forms a gas passage for supplying hydrogen gas and an oxidant to both sides of the membrane-electrode assembly 12 and connects the anode electrode and the cathode electrode in series.

In addition, as illustrated in FIG. 1, a pressure plate 13 may be disposed at the outermost portion of the stack 10 to closely contact the plurality of electricity generating units 11. Alternatively, the separator 16 positioned at the outermost portion of the plurality of electricity generating units 11 may be configured to take the role of the pressing plate. Moreover, the press plate 13 can be comprised so that it may have a function unique to the separator 16 in addition to the function which keeps the some electricity generation part 11 in close contact.

The pressurizing plate 13 includes a first injection unit 13a for supplying hydrogen gas generated from the reformer 30 to the electricity generation unit 11, and an oxidant supplied from the oxidant supply unit 70. 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 membrane-electrode assembly 12, and a membrane-electrode assembly ( A second discharge portion 13d for discharging the unreacted oxidant containing water generated by the combined reaction of hydrogen and oxidant at the cathode electrode of 12) is formed. Preferably, the oxidant is oxygen, and when the oxidant is oxygen, the oxidant supply unit 70 may supply air.

The reformer 30 is configured to generate hydrogen gas from fuel through a chemical catalytic reaction by thermal energy, and to reduce the concentration of carbon monoxide contained in the hydrogen gas.

The reformer 30 includes a heat source unit 31 for generating heat energy at a predetermined temperature through an oxidation catalyst reaction between a liquid fuel and an oxidant, and a steam reforming (SR) catalyst reaction by the heat energy. A reforming reaction unit 32 for generating hydrogen gas from fuel, and at least one carbon monoxide reduction device 33 according to the present invention for reducing the concentration of carbon monoxide contained in the hydrogen gas through an oxidation reaction of the hydrogen gas. do.

The heat source part 31 is connected to the fuel tank 51 by the first supply line 91 in the form of a pipe, and is connected to the oxidant pump 71 by the second supply line 92 in the form of a pipe to form a liquid phase. Pass the fuel and oxidant. The heat source portion 31 includes a catalyst layer (not shown) which promotes an oxidation reaction between the fuel and the oxidant to generate the heat energy. At this time, the heat source portion 31 is provided in the form of a plate that forms a channel (not shown) to enable the flow of liquid fuel and oxidant has a structure in which the catalyst layer is coated on the surface of the channel. . Alternatively, the heat source part 31 may be provided in a cylindrical shape having a predetermined internal space to form a catalyst module or a honeycomb type catalyst module filled in the internal space with a catalyst layer, for example, a pellet. .

The reforming reaction unit 32 absorbs heat energy generated from the heat source unit 31 to generate hydrogen gas from the fuel through a steam reforming catalytic reaction of the fuel supplied from the fuel tank 51. The reforming reaction part 32 is connected to the heat source part 31 by a third supply line 93 in the form of a pipe. The reforming reaction section 32 is provided with a catalyst layer (not shown) for promoting the steam reforming reaction of the fuel to generate the hydrogen gas.

Carbon monoxide reduction device 33 is a carbon monoxide contained in the hydrogen gas through a selective reaction (Preferential CO Oxidation (PROX) PROX) catalytic reaction of the hydrogen gas generated from the reforming reaction unit 32 and the oxidant supplied from the oxidant pump 71 Reduce the concentration of The carbon monoxide reduction device 33 is connected to the reforming reaction part 32 by a fourth supply line 94 in the form of a pipe, and is connected to the oxidant pump 71 by the fifth supply line 95 in the form of a pipe. It is installed to pass the hydrogen gas and the oxidant.

In addition, the carbon monoxide reduction device 33 includes a first reactor having a first carbon monoxide oxidation catalyst for performing an oxidation catalytic reaction with carbon monoxide in a reformed fuel; And a second reactor having a second carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in a reformed fuel, wherein the carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst, and then to the second reactor. It is preferable that the carbon monoxide reduction device 33 of the present invention be supplied and react with the second carbon monoxide oxidation catalyst. In addition, the temperature inside the first reactor is reduced to the second carbon monoxide oxidation catalyst reaction temperature according to the flow direction of the reforming fuel, and the temperature inside the second reactor is maintained at the second carbon monoxide oxidation catalyst reaction temperature. .

At this time, the carbon monoxide reduction device 33 and the first injection portion 13a of the stack 10 are connected to each other by a sixth supply line 96 in the form of a pipe, and thus the carbon monoxide reduction device 33 It is made of a structure capable of supplying the hydrogen gas of reduced concentration to the electricity generating unit 11 of the stack (10). In addition, the carbon monoxide reduction apparatus 33 may be formed of stainless steel, aluminum, copper, iron, or the like having thermal conductivity.

Hereinafter, with reference to the accompanying drawings an embodiment of the carbon monoxide reduction device 33 of the reformer 30 will be described in detail.

2 is a perspective view of the carbon monoxide reduction device 33 according to an embodiment of the present invention, Figure 3 is a block diagram schematically showing the carbon monoxide reduction device 33 of FIG.

2 and 3, the carbon monoxide reduction apparatus includes a first reactor 110 and a second reactor 120. The first reactor 110 and the second reactor 120 may be manufactured in various forms, preferably in the form of a tube having a predetermined internal space. The first reactor 110 and the second reactor 120 are provided with inlets 111 and 121 for injecting the reactants and outlets 112 and 122 for discharging the product, respectively. The first reactor and the second reactor are each provided with a first carbon monoxide oxidation catalyst 113 and a second carbon monoxide oxidation catalyst 123.

Although not shown in FIG. 3, a heat exchanger, a cooler, or a heater for reducing the temperature inside the first reactor 110, and a heat exchanger, a cooler, for maintaining a constant temperature inside the second reactor 120, Or it may further comprise a heater.

The first carbon monoxide oxidation catalyst 113 and the second carbon monoxide oxidation catalyst 123 may be formed on an inner surface of a channel formed on the substrate when the first reactor and the second reactor body are composed of a reaction substrate, and the reactor When the main body is formed in a tubular form, it is preferable that the main body is formed in a pellet or honey comb type and filled in the inner space of the reactor.

The carbon monoxide reduction apparatus includes a pipeline 130 connecting the outlet 112 of the first reactor and the inlet 121 of the second reactor. In addition, it may optionally include a housing 140 to isolate the first reactor and the second reactor from the outside, and an isolation unit 150 to isolate the pipeline from the outside.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited to the following examples.

(Example 1)

5.2981 g of Ce (NO ₃ ) ₂ .6H ₂ O and 0.0386 g of Ni (NO ₃ ) ₂ .6H ₂ O were dissolved in 10 ml of an aqueous solution of Cu (NO ₃ ) ₂ · 3H ₂ O to prepare a solution. To the solution was added 20 ml of Al ₂ O ₃ (14.84 g). The solution was stirred while heating while giving a temperature change as shown in FIG. 4, followed by drying to prepare a first carbon monoxide oxidation catalyst. The prepared first carbon monoxide oxidation catalyst was 0.1 wt% NiO, 4 wt% CuO, 21 wt% CeO ₂ , and 74.9 wt% Al ₂ O ₃ .

The carbon monoxide oxidation catalyst 2 was used as a Pt / Al ₂ O ₃ (trade name: NEP-TM752) supported with 0.12% by weight of Pt on an Al ₂ O _3.

As shown in FIG. 2, the first reactor and the second reactor were manufactured in a tubular form, and the prepared first carbon monoxide oxidation catalyst was charged to 10 ml in the first reactor, and the second carbon monoxide oxidation catalyst was charged in 10 ml to the second reactor. An abatement device was manufactured.

(Comparative Example 1)

Preparing a tubular reactor, and by the Pt / Al ₂ O ₃ (Engelhard Corp.) Pt-supported with 0.12% by weight of Al ₂ O ₃ to the reactor charge was prepared in 30ml of carbon monoxide reducing device.

(Comparative Example 2)

Neutral water and aluminum isopropoxide were mixed at 80 ° C., stirred for 30 minutes, and HNO ₃ was added to prepare an aluminum hydroxide sol. Hydrogen hexachloroplatinate (IV) hydrate was mixed with 1,3-butanediol to prepare a solution, and Pt was added to the solution to prepare a precursor solution. Prepared. The precursor solution and the aluminum hydroxide sol were mixed at room temperature and stirred until gelation occurred. The gel obtained was dried in air at 110 ° C. for 1 day and then calcined at 500 ° C. for 13 hours to obtain a catalyst mass. The catalyst agglomerates were pulverized to prepare a carbon monoxide oxidation catalyst having Pt supported by 2 wt% on Al ₂ O ₃ .

A reactor in the form of a tube was prepared, and the reactor was filled with 70 ml of a carbon monoxide oxidation catalyst prepared in Comparative Example 2 to prepare a carbon monoxide reduction device.

The carbon monoxide reduction device prepared in Example 1 has a temperature of 200 ° C., CO ₂ is 14.66%, H ₂ is 39.97%, N ₂ is 12.29%, CH ₄ is 0.33%, CO is 0.31%, and O ₂ is 0.25. %, A gas having a H ₂ O of 32.19% was flowed under conditions of a flow rate of 1658.6667 ml / min, a space velocity of 4976h ^-1 . In the case of the carbon monoxide reduction device manufactured in Example 1, it was confirmed that the temperature at the first reactor outlet was 120 ° C.

The temperature inside the second reactor of the carbon monoxide reduction device manufactured in Example 1 was constantly maintained at 110 ° C., 120 ° C., 130 ° C., 140 ° C., and 150 ° C., respectively, and CO at the second reactor outlet at each temperature. Emission concentrations, CO conversion, and CO selectivity were measured and the results are shown in FIG. 5.

Referring to FIG. 5, when the temperature inside the second reactor is 110 ° C. to 130 ° C., it can be seen that the CO emission concentration is 1 ppm or less. However, the CO conversion rate was 99% regardless of the temperature within the above temperature range, and the CO selectivity was almost constant at 60%.

In the carbon monoxide reducing device prepared in Comparative Example 1, a gas containing 15.8% of CO ₂ , 57.9% of H ₂ , 5.05% of N ₂ , 0.5% of CO, 0.75% of O ₂ , and 20.0% of H ₂ O was spaced. The velocity was flowed under the condition of 5000h ⁻¹ , and CO ₂ was 0-25%, H ₂ was 60%, N ₂ was 5.05%, CO was 1%, and O ₂ was 0.5 to 1.35% of the remaining gas was H ₂ O or He at a flow rate of 40 ml / min.

The residual ratio of the hydrogen gas of the carbon monoxide reduction apparatuses manufactured in Example 1 and Comparative Examples 1 to 2 was measured, and the results are shown in FIG. 6. Referring to FIG. 6, the carbon monoxide reduction apparatus manufactured in Example 1 had a residual ratio of hydrogen gas of 99.5%, and the carbon monoxide reduction apparatus manufactured in Comparative Example 1 had a residual ratio of hydrogen gas of 98.43%. In the case of the carbon monoxide reduction device manufactured in 2, it can be seen that the hydrogen gas residual ratio is 99.15%. Thus, the carbon monoxide reduction device prepared in Example 1 contains the smallest amount of Pt but has the highest hydrogen gas residual rate.

All simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

The carbon monoxide reduction device of the reformer for a fuel cell of the present invention can ensure the activity and selectivity of a high carbon monoxide oxidation reaction while having a simple structure. In addition, by using the carbon monoxide reduction device of the reformer for a fuel cell of the present invention, the content of carbon monoxide in the reforming reaction can be lowered in ppm units.

Claims (32)

A first reactor having a first carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in the reformed fuel; And A second reactor with a second carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in the reformed fuel, The carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst, and then supplied to the second reactor to react with the second carbon monoxide oxidation catalyst, And said first carbon monoxide oxidation catalyst has a higher selectivity for carbon monoxide oxidation than said second carbon monoxide oxidation catalyst. The method of claim 1, The first reactor has a first inlet for supplying carbon monoxide at one end, and a first outlet for discharging carbon monoxide at the other end; The second reactor has a second inlet for supplying carbon monoxide at one end, and a second outlet for discharging carbon monoxide at the other end, And a first outlet of the first reactor and a second inlet of the second reactor are connected to each other. The method of claim 1, The carbon monoxide reduction device has a U-shape, And a first carbon monoxide oxidation catalyst on one side of the U-shaped column, and a second carbon monoxide oxidation catalyst on the other side of the U-shaped column. The method of claim 1. The first reactor and the second reactor is a carbon monoxide reduction device of a fuel cell reformer is installed in one housing. delete The method of claim 1, Wherein the first carbon monoxide oxidation catalyst comprises an active material comprising CeO ₂ , and CuO. The method of claim 6, The first carbon monoxide oxidation catalyst comprises CeO ₂ , MO and CuO in a weight ratio of 15 to 25: 0.1 to 0.4: 1 to 10 carbon monoxide reduction device of a fuel cell reformer. The method of claim 6, The first carbon monoxide oxidation catalyst is a carbon monoxide reduction device of a reformer for a fuel cell, wherein the active material is supported on a carrier selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and combinations thereof. The method of claim 1, Wherein said first carbon monoxide oxidation catalyst comprises an active material comprising CeO ₂ , MO (where M is a transition metal) and CuO. The method of claim 9, Wherein M is selected from the group consisting of Ni, Co, Fe, Sn, Pb, Se, and combinations thereof. The method of claim 10, Wherein M is Ni Carbon monoxide reduction device of a fuel cell reformer. The method of claim 9, The first carbon monoxide oxidation catalyst comprises CeO ₂ , MO and CuO in a weight ratio of 15 to 25: 0.1 to 0.4: 1 to 10 carbon monoxide reduction device of a fuel cell reformer. The method of claim 9, The first carbon monoxide oxidation catalyst is a carbon monoxide reduction device of a reformer for a fuel cell, wherein the active material is supported on a carrier selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and combinations thereof. The method of claim 1, The second carbon monoxide oxidation catalyst comprises a carbon monoxide reduction device of a reformer for a fuel cell comprising an active material containing a Pt-based metal. The method of claim 14, The Pt-based metal is a carbon monoxide reduction device of a reformer for a fuel cell that is selected from the group consisting of Pt, Rh, Ru, and combinations thereof. The method of claim 14, The second carbon monoxide oxidation catalyst is characterized in that the active material is graphite, denka black, ketjen black, acetylene black, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanoballs, activated carbon, alumina, silica, zirconia, titania, and An apparatus for reducing carbon monoxide in a reformer for a fuel cell, which is supported on a carrier selected from the group consisting of a combination of these. A first reactor having a first carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in the reformed fuel; And A second carbon monoxide oxidation catalyst for oxidative catalytic reaction with carbon monoxide in the reformed fuel, comprising a second reactor connected to the first reactor, The carbon monoxide is supplied to the first reactor to react with the first carbon monoxide oxidation catalyst, and then supplied to the second reactor to react with the second carbon monoxide oxidation catalyst, The temperature inside the first reactor is reduced to the second carbon monoxide oxidation catalyst reaction temperature in accordance with the flow direction of the reforming fuel, the temperature inside the second reactor is maintained at the second carbon monoxide oxidation catalyst reaction temperature Carbon monoxide reduction device. The method of claim 17, And said first carbon monoxide oxidation catalyst has a higher selectivity for carbon monoxide oxidation than said second carbon monoxide oxidation catalyst. The method of claim 17, And said first carbon monoxide oxidation catalyst comprises an active material comprising CeO ₂ and CuO. The method of claim 19, The first carbon monoxide oxidation catalyst comprises CeO ₂ , and CuO in a weight ratio of 15 to 25: 1 to 10 carbon monoxide reduction device of a fuel cell reformer. The method of claim 19, The first carbon monoxide oxidation catalyst is a carbon monoxide reduction device of a reformer for a fuel cell, wherein the active material is supported on a carrier selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and combinations thereof. The method of claim 17, Wherein said first carbon monoxide oxidation catalyst comprises an active material comprising CeO ₂ , MO (where M is a transition metal) and CuO. The method of claim 22, Wherein M is selected from the group consisting of Ni, Co, Fe, Sn, Pb, Se, and combinations thereof. The method of claim 23, wherein Wherein M is Ni Carbon monoxide reduction device of a fuel cell reformer. The method of claim 22, The first carbon monoxide oxidation catalyst comprises CeO ₂ , MO and CuO in a weight ratio of 15 to 25: 0.1 to 0.4: 1 to 10 carbon monoxide reduction device of a fuel cell reformer. The method of claim 22, The first carbon monoxide oxidation catalyst is a carbon monoxide reduction device of a reformer for a fuel cell, wherein the active material is supported on a carrier selected from the group consisting of Al ₂ O ₃ , TiO ₂ , SiO ₂ , and combinations thereof. The method of claim 17, The second carbon monoxide oxidation catalyst comprises a carbon monoxide reduction device of a reformer for a fuel cell comprising an active material containing a Pt-based metal. The method of claim 27, The Pt-based metal is a carbon monoxide reduction device of a reformer for a fuel cell that is selected from the group consisting of Pt, Rh, Ru, and combinations thereof. The method of claim 27, The second carbon monoxide oxidation catalyst is characterized in that the active material is graphite, denka black, ketjen black, acetylene black, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanoballs, activated carbon, alumina, silica, zirconia, titania, and An apparatus for reducing carbon monoxide in a reformer for a fuel cell, which is supported on a carrier selected from the group consisting of a combination of these. The method of claim 17, The first carbon monoxide oxidation catalyst includes an active material including CeO ₂ , NiO and CuO, The second carbon monoxide oxidation catalyst comprises a Pt carbon monoxide reduction device of a reformer for a fuel cell. The method of claim 30, The temperature at the first reactor outlet is 110 to 130 ℃ carbon monoxide reducing device of a reformer for a fuel cell. A reforming reaction unit generating hydrogen gas from the fuel through a reforming catalytic reaction by thermal energy; The carbon monoxide reducing unit includes a reformer for a fuel cell comprising the carbon monoxide reducing device according to any one of claims 1 to 4 and 6 to 31; At least one electricity generating unit generating electrical energy through an electrochemical reaction between the hydrogen gas and an oxidant; A fuel supply unit supplying the fuel to the reforming reaction unit; And Oxidant supply unit for supplying an oxidant to the electricity generating unit Fuel cell system comprising a.

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