KR100746344B1 - Micro channel reactor with combustion catalyst layer - Google Patents

Abstract

A micro channel reactor which can improve adhesive force of the reforming catalyst by coating a reforming catalyst on the oxide layer after coating micro channels with an oxide layer, and can effectively supply heat required in a reforming reaction for producing hydrogen to the micro channel reactor by containing a combustion catalyst layer having a combustion catalyst added thereto in the micro channel reactor is provided. A micro channel reactor containing a combustion catalyst comprises: an upper gasket(10) having an inlet(3) for flowing in a hydrogen producing raw material, and an outlet(4) for flowing out water and combustion gas; a reforming catalyst layer(20) having an inflow hole(20-2) formed at one end of channels and communicated with the inlet of the upper gasket, a discharge hole(20-3) formed at the other end of the channels, and a through hole(20-1) formed at one side of an outer part of the channels and communicated with the outlet of the upper gasket; a combustion catalyst layer(30) having an inflow hole(30-2) formed at one end of the channels, a discharge hole(30-2) formed at the other end of the channels and communicated with the through hole of the reforming catalyst layer, and a through hole(30-1) formed at one side of an outer part of the channels and communicated with the discharge hole of the reforming catalyst layer; and a lower gasket(10') having an inlet(3') for flowing in a combustion reactant, and an outlet(4') for flowing out hydrogen and gas.

Description

Micro channel reactor with combustion catalyst layer

FIG. 1A is a perspective view of a reforming catalyst layer showing channels formed on a substrate in the microchannel reactor of the present invention, and FIG. 1B is a cross-sectional view showing a cross section of the microchannel reactor.

Figure 2a is an example of an exploded perspective view of the microchannel reactor of the present invention, Figure 2b is an example of the microchannel reactor of the present invention, Figure 2c is a photograph showing another example of the microchannel reactor of the present invention.

3A is a channel image in a microchannel reactor without catalyst coating.

3B shows an image of a micro channel coated with a Cu / ZnO / Al ₂ O ₃ catalyst.

3C shows an image of a micro channel coated with Pt / ZrO ₂ catalyst.

4A shows an image of a Pt / ZrO ₂ coated microchannel after 72 hours combustion reaction.

4b shows a cross-sectional image of a Pt / ZrO ₂ coated microchannel after 72 hours combustion reaction.

5 is a graph showing the performance of the combustor over time.

6 is a graph showing the performance of the combustor according to the flow rate of the combustion reactants.

7 is a graph showing the inlet and outlet temperatures of the micro reformer according to the combustion reactants.

8 is a graph showing the conversion of methanol with temperature.

9 is a graph showing the reformed gas composition and hydrogen production according to temperature.

10 is a graph showing the conversion rate according to the feed amount of the reforming reactant.

<Explanation of symbols for main parts of the drawings>

1 channel 2 substrate

3: upper gasket inlet 3 ': lower gasket inlet

4: Upper Gasket Outlet 4 ': Lower Gasket Outlet

10: upper gasket 10 ': lower gasket

20: reforming catalyst layer 30: combustion catalyst layer

The present invention relates to a micro channel reactor containing a combustion catalyst bed.

In the microchannel reactor containing the combustion catalyst layer of the present invention, the microchannel reactor includes a combustion catalyst layer in a channel of the substrate so that the heat of reaction generated by the reaction between the combustion fuel and the combustion catalyst can be used for the reforming reaction for hydrogen generation. Micro channel reactor containing a combustion catalyst bed.

On the other hand, the microchannel reactor of the present invention can improve the adhesion between the microchannel and the combustion catalyst and the reforming catalyst by coating an oxide layer on the microchannel with respect to the combustion catalyst layer and / or reforming catalyst layer provided in the channel of the substrate.

In the microchannel reactor of the present invention, a plurality of microchannels are formed in a substrate, and a substrate having the microchannels formed between the upper gasket and the lower gasket is stacked as a reforming catalyst layer and a combustion catalyst layer.

Hydrogen production for driving portable fuel cells is advantageously made using microchannel reactors that are compact in size, easy to heat and mass transfer, and methanol that can be reformed at relatively low temperatures. Microchannel reactors can be expected to have high activity because of their low heat and mass transfer resistance even at high flow rates. Since the reforming reaction of methanol in a reforming catalyst such as Cu / ZnO / Al ₂ O ₃ is an endothermic reaction, it is necessary to attach a combustor for supplying heat required for the reforming reaction in order to apply it to a portable fuel cell.

Fuel cells are attracting attention as future energy sources because they are environmentally friendly and have high energy conversion efficiency. In particular, PEMFC (proton exchange membrane fuel cell) is a fuel cell that can replace a lithium secondary battery, and has high specific power, power density, and durability. However, because the storage and transportation of hydrogen for PEMFC is not easy, there is an active research on onboard fuel reforming for hydrogen production.

The reforming reaction for hydrogen production can be classified into three types: pyrolysis process, partial oxidation reaction, and steam reforming reaction. The steam reforming reaction using the double methanol has been considered as a reforming reaction for a portable fuel cell because of the high hydrogen concentration and the small amount of carbon monoxide that poisons the electrode of the PEMFC. The reforming reaction using methanol is an endothermic reaction, and since the temperature at which the reaction takes place actively is 200 ° C. or more, the heat of reaction is essential in the methanol reforming reaction. Since the research so far is in the early stages, the heat required for the methanol reforming reaction is mainly supplied from the outside.

Until now, research on hydrogen production using a micro reactor such as a micro channel reactor is as follows. Electrochimica Acta, 50, 719, developed a reformer with a vaporizer of size 70mm × 40mm × 30mm and supplied the heat for steam reforming using electric heat. About 10W of electricity was produced using the prepared microreactor. In IMRET 6 and 167, a microreactor was manufactured using a stainless steel plate processed with 62 microchannels, and about 15.9g of methanol synthesis catalyst was prepared. ) Was used. A methanol conversion of 90% or more was obtained at a temperature range of 250 to 270 ° C.

Micro-channel reactors have several advantages, such as small size, low heat and mass transfer resistance, but the problem of the catalyst layer falling off during the reaction due to the lack of adhesion between the stainless steel plate and the catalyst has been found. In addition, a means for effectively supplying the heat required for the methanol steam reforming reaction is essential.

In order to achieve the above-mentioned object, the present invention is to coat the oxide layer on the micro-channel for obtaining a stable coating layer with the reforming catalyst in the micro-channel reactor for generating hydrogen and then to coat the reforming catalyst on the oxide layer to improve the adhesion of the reforming catalyst It is an object to provide a micro channel reactor that can be improved.

 Meanwhile, another object of the present invention is to provide a micro channel reactor having a combustion catalyst layer in which a combustion catalyst is added inside the micro channel reactor so as to effectively supply heat required for the reforming reaction for generating hydrogen in the micro channel reactor.

The present invention for achieving the above-mentioned object is an upper gasket having an inlet for introducing the hydrogen-producing raw material and an outlet for discharging water and combustion gas,

An oxide layer is coated on the channel of the substrate, and a hydrogen generation reforming catalyst is coated on the oxide layer to promote hydrogen generation from the hydrogen generating raw material, and at one end of the channel is in communication with the inlet of the upper gasket and the hydrogen generating raw material is introduced into the channel. A reforming catalyst layer having an inlet hole formed therein and the other end of the channel having a discharge hole through which a reactant of a hydrogen generating raw material is discharged, and having a through hole communicating with an outlet of the upper gasket on one side of the channel;

An oxide layer is coated on the channel of the substrate, and a combustion catalyst reacting with the combustion reactant is coated on the oxide layer, and one end of the channel forms an inlet hole through which the combustion reactant enters the channel of the combustion catalyst layer, while the other end of the channel is It is in communication with the through-holes of the reforming catalyst layer and has a discharge hole for discharging the reactants produced by the reaction of the combustion reactant and the combustion catalyst, and in communication with the discharge hole for discharging the reactants of the hydrogen-producing raw material of the reforming catalyst layer on one side outside the channel Combustion catalyst layer having a through hole,

A lower gasket having an inlet through which a combustion reactant is introduced and an outlet through which the hydrogen and gas, which is a reactant of a hydrogen generating raw material, is discharged in communication with the through hole of the combustion catalyst layer, wherein the upper gasket, the reforming catalyst layer, the combustion catalyst layer and the lower gasket A micro channel reactor containing this integrally stacked combustion catalyst layer is shown.

The channel of the conventional micro channel reactor is coated with a reforming catalyst that reacts with the hydrogen generating raw material supplied from the outside of the reactor to produce hydrogen. That is, the reforming catalyst coated on the channel reacts with the hydrogen generating feedstock flowing through the channel to produce hydrogen and other gases. At this time, the hydrogen generating raw material uses methanol which can be reformed at a relatively low temperature. However, the reaction between methanol and the reforming catalyst to generate hydrogen is endothermic, and therefore, external heat must be supplied.

The present invention has been devised to solve this problem, it is possible to supply the heat of reaction required for the reaction of methanol and reforming catalyst in the micro-channel reactor.

In order to supply the heat of reaction inside the microchannel reactor, a combustion catalyst layer coated with a combustion catalyst is provided in a channel equipped with a conventional reforming catalyst, and a combustion reactant capable of reacting with the combustion catalyst layer to generate heat of reaction is supplied from outside the microchannel reactor. By reacting with the combustion reactant and the combustion catalyst of the combustion catalyst layer it is possible to obtain the heat of reaction required for hydrogen generation in the reforming catalyst layer.

The combustion catalyst layer acts as a combustor because it supplies the reaction heat necessary to generate hydrogen by reforming methanol as a hydrogen generating raw material.

In addition, the conventional micro-channel reactor has a poor adhesion between the reforming catalyst and the combustion catalyst with a metal which is a material of the micro-channel reactor, resulting in loss of the catalyst and consequently reducing hydrogen production.

This problem can be solved if the bonding force between the micro channel reactor and the reforming catalyst and the combustion catalyst is good. In order to solve the above problems, the microchannel reactor of the present invention coats an oxide layer on the channel of the microchannel reactor to improve the bonding strength between the microchannel reactor, the reforming catalyst, and the combustion catalyst, and then reformats and the combustion catalyst on the oxide layer. Lower reforming catalysts and combustion catalysts can prevent direct contact with the metal and consequently improve the adhesion between the reforming catalyst and the combustion catalyst in the micro channel reactor.

Hereinafter, the microchannel reactor containing the combustion catalyst layer of the present invention will be described in more detail with reference to the accompanying drawings.

Figure 1a is a perspective view showing that the channel 1 is formed on the substrate 2, the through-hole 20-1 is formed on one side of the substrate in the microchannel reactor of the present invention, Figure 1a is a microchannel reactor of the present invention The reformed catalyst layer 20 is coated with a reforming catalyst in the channel.

FIG. 1B is a cross-sectional view of the substrate on which the channel is formed in FIG. 1A.

2A is an exploded perspective view of a microchannel reactor of the present invention in which an upper gasket 10, a reforming catalyst layer 20, a combustion catalyst layer 30, and a lower gasket 10 ′ are sequentially stacked.

The microchannel reactor of the present invention includes a pair of the reforming catalyst layer 20 and the combustion catalyst layer 30 stacked between the upper gasket 10 and the lower gasket 10 '.

2B is a microchannel reactor according to another embodiment of the present invention, in which a pair of three stacked microchannel reactors in which a reforming catalyst layer 20 and a combustion catalyst layer 30 are stacked between an upper gasket 10 and a lower gasket 10 '. to be. In this case, a gasket 11 may be provided between the reforming catalyst layer 20 and the combustion catalyst layer 30 to prevent leakage of gas in each catalyst layer.

FIG. 2C is another example microchannel reactor of the present invention having a microchannel reactor as shown in FIG. 2B and having a housing outside the microchannel reactor, while compressing the microchannel reactor inside the housing outside the housing. Photo shows a micro channel reactor with a crimping means.

Referring to the configuration of the present invention with reference to Figure 2a in more detail as follows.

The micro-channel reactor of the present invention has an upper gasket (10) having an inlet (3) into which the hydrogen-producing raw material is introduced and an outlet (4) through which water and combustion gas are discharged;

An oxide layer is coated on the channel 1 of the substrate 2, and a hydrogen generation reforming catalyst is coated on the oxide layer to promote hydrogen production from the hydrogen generating raw material, and at one end of the channel is in communication with the inlet of the upper gasket and the hydrogen generating raw material. An inlet hole 20-2 through which a gas is introduced into the channel is formed, while the other end of the channel has a discharge hole 20-3 through which the reactant of the hydrogen-producing raw material is discharged, and an outlet of the upper gasket is provided on one side of the channel. Reform catalyst layer 20 having a through-hole 20-1 in communication with,

An oxide layer is coated on the channel 1 of the substrate 2, and a combustion catalyst reacting with the combustion reactant is coated on the oxide layer, and one end of the channel has an inlet hole 30-2 through which the combustion reactant flows into the channel of the combustion catalyst layer. ) Is formed while the other end of the channel is in communication with the through hole 20-1 of the reforming catalyst layer and has a discharge hole (30-3) through which the reactants produced by the reaction of the combustion reactant and the combustion catalyst are discharged. Combustion catalyst layer 30 having a through hole (30-1) in communication with the discharge hole through which the reactant of the hydrogen-producing raw material of the reforming catalyst layer is discharged on one side of the outside,

A lower gasket 10 'having an inlet port 3' through which a combustion reactant flows and a discharge port 4 'through which a hydrogen and gas which is a reactant of a hydrogen generating raw material are discharged, which is in communication with the through hole 30-1 of the combustion catalyst layer; And a microchannel reactor containing a combustion catalyst layer in which the upper gasket 10, the reforming catalyst layer 20, the combustion catalyst layer 30, and the lower gasket 10 'are integrally stacked.

The micro-channel reactor is a reforming catalyst layer 20 through the inlet hole 20-2 formed on one side of the substrate of the reforming catalyst layer 20 and the inlet 3 of the upper gasket 10 and methanol, which is a hydrogen generating raw material When moved to the channel (1) of the reforming catalyst provided in the channel (1) promotes the reaction of methanol and water to generate a gas such as hydrogen, carbon monoxide, carbon dioxide. Gases such as hydrogen, carbon monoxide, and carbon dioxide generated by the reforming catalyst of methanol, water, and the reforming catalyst layer are formed in the inlet hole 20-3 formed on the other side of the substrate of the reforming catalyst layer 20 and the combustion catalyst layer 30 described below. It is discharged to the outside of the micro channel reactor through the through hole 30-1 formed on one side of the channel and the outlet 4 'of the lower gasket (see the solid line in FIG. 2A). Only hydrogen may be collected separately from the released gases such as hydrogen, carbon monoxide and carbon dioxide. At this time, gas, such as hydrogen, carbon monoxide, and carbon dioxide, generated by methanol, water, and the reforming catalyst in the reforming catalyst layer 20 is introduced into the combustion catalyst layer 30 under the reforming catalyst layer 20, and the combustion reactant in the combustion catalyst layer A gasket may be provided between the reforming catalyst layer 20 and the combustion catalyst layer 30 provided and stacked below the reforming catalyst layer 20 in order to prevent the reaction of the combustion catalyst.

Meanwhile, the methanol and water are introduced through the inlet 3 of the upper gasket 10, and at the same time, the combustion reactants are located at one side of the inlet 3 ′ of the lower gasket 10 ′ and the channel 1 of the combustion catalyst layer 30. Moving to the channel 1 of the combustion catalyst layer 30 through the formed inlet hole 30-2, the combustion catalyst coated on the channel 1 of the combustion catalyst layer 30 reacts with the combustion reactants. When the combustion reactant reacts with the combustion catalyst, the combustion gas generated by the exothermic reaction that generates combustion gas such as carbon dioxide, carbon monoxide and water vapor is discharge holes 30 formed at one side of the channel 1 of the combustion catalyst layer 30. -3) is discharged out of the reactor through the through hole 20-1 of the reforming catalyst layer 20 and the outlet 4 of the upper gasket (see dashed line in FIG. 2A).

The reaction of the combustion reactant and the combustion catalyst in the combustion catalyst layer 30 is an exothermic reaction, and the reaction heat generated by the exothermic reaction is transferred to the reforming catalyst layer 20 laminated with the combustion catalyst layer 30 through conduction, and the reforming catalyst layer In channel (1) of (20) serves as a heat source necessary for the reaction of methanol and water.

 In FIG. 2A, the flow direction of methanol and water during the reaction of methanol and water in the reforming catalyst layer 20 (see solid line) and the flow direction of the combustion reactant during the reaction of the combustion reactant and the combustion catalyst in the combustion catalyst layer 30 (see dotted line) Counter flows face each other. However, if the channel type and the position of the holes of the reforming catalyst layer and the combustion catalyst layer are properly changed, the methanol and water reaction in the reforming catalyst layer 20 and the flow direction of methanol and water and the reaction of the combustion reactant and the combustion catalyst in the combustion catalyst layer 30 The flow direction of the combustion reactants can be the same flow direction.

In the micro-channel reactor containing the combustion catalyst layer 30 of the present invention, the reforming catalyst layer 20 may be located above or below the combustion catalyst layer 30. For example, as described with reference to FIG. 2A, when the hydrogen generating raw material flows in from the top, the reforming catalyst layer 20 may be positioned above the combustion catalyst layer 30. In addition, when the hydrogen-producing raw material flows in from the bottom, the reforming catalyst layer may be located below the combustion catalyst layer.

The reforming catalyst layer 20 and the combustion catalyst layer 30 of the microchannel reactor of the present invention may be distinguished according to the type of catalyst coated on the channel 1 in the substrate 2 on which the channel 1 is formed. For example, after the oxide layer is coated on the channel 1 of the substrate 2, the reforming catalyst may be coated on the oxide layer to be used as the reforming catalyst layer 20. After the oxide layer is coated on the channel 1 of the substrate 2, the combustion catalyst is coated on the oxide layer to be used as the combustion catalyst layer 30.

The channel formed in the substrate may include a plurality of channels, wherein the channel has a predetermined width and depth. For example, in the micro-channel reactor of the present invention, the channels in the reforming catalyst layer 20 and / or the combustion catalyst layer 30 may be processed to a length of 45 mm, a width of 1 mm, and a depth of 0.5 mm so that 10 such channels are formed. In the microchannel reactor of the present invention, channels such as the length, number, width, and depth of the channels are not limited to those mentioned above, and the length, number, width, and depth of the channels are those skilled in the art. Since it can be carried out by selecting the enemy, detailed description thereof will be omitted.

In the microchannel reactor of the present invention, the substrate 2 constituting the reforming catalyst layer 20 and / or the combustion catalyst layer 30 has a high thermal conductivity in order to transfer reaction heat generated in the combustion catalyst layer 30 to the reforming catalyst layer 20 by conduction. It is better to use high materials. As one of these materials it is possible to use metal, more preferably stainless steel.

The reforming catalyst of the reforming catalyst layer in the microchannel reactor containing the combustion catalyst layer of the present invention may be used as long as it is a catalyst capable of generating hydrogen by promoting the reaction between methanol, which is a hydrogen generating raw material, and water in the conventional microchannel reactor. As one example of the reforming catalyst in the present invention, any one or more selected from Cu / ZnO / Al ₂ O ₃ , Ni / Al ₂ O ₃ , Pd / Al ₂ O ₃ , and Ph / Al ₂ O ₃ may be used.

In the microchannel reactor containing the combustion catalyst bed of the present invention, the combustion catalyst bed, which serves as a combustor for providing the heat of reaction from the reforming catalyst bed to the reforming reaction, reacts with the combustion reactants entering the microchannel reactor to produce a reactant. In this case, the combustion reactant may include vaporized methanol, for example, vaporized methanol and air, and the combustion catalyst may be any catalyst capable of reacting with the combustion reactant including vaporized methanol to generate heat of reaction. . As an example of the combustion catalyst in the present invention, a combustion catalyst impregnated with at least one precious metal selected from Pt, Pd, Rh, Au, Ni, and Ru, preferably Pt / ZrO ₂ , Pt / Al ₂ O ₃ , Pd / Al At least one selected from ₂ O ₃ and Pt / CeO ₂ may be used. Meanwhile, oxygen may be used instead of air, which is one of the combustion reactants.

In the above, the combustion catalyst may be commercially available as a commercially available product or may be manufactured and used directly.

As an example of the production of the combustion catalyst, the combustion catalyst may be prepared using an impregnation method. In general, the metal impregnated with the combustion catalyst may use any one or more precious metals selected from Pt, Pd, Rh, Au, Ni, and Ru. Precursors of precious metals are in the form of nitrides, which are easily soluble in solvents. The support material is added to the solution, and the solvent is dried using a vacuum evaporator after stirring for a predetermined time. . After drying, the catalyst can be calcined at high temperature in order to remove unnecessary components present in the catalyst.

Examples of the noble metal precursors include tetraamine paltinum (II) nitrate, tetraammineplatinum (II) chloride monohydrate, platinum chloride and tetraamineplatinum hydroxide hydrate. One or more selected may be used, and one or more selected from among ZrO ₂ , Al ₂ O ₃ , TiO ₂ , and SiO ₂ may be used as an example of the support.

The drying can be carried out to the extent that the solvent can be removed, and the firing can be carried out to the extent that an unnecessary component can be removed from the catalyst. As an example of such drying and firing, drying may be performed at 100 to 110 ° C. for 1 to 2 hours, and firing at 400 to 600 ° C. for 1 to 3 hours.

In the microchannel reactor containing the combustion catalyst layer of the present invention, the reforming catalyst and the combustion catalyst formed in the channel are coated with an oxide layer on the channel, and then the reforming catalyst and the combustion catalyst are coated on the oxide layer, and the channel and the reforming catalyst of the microchannel reactor and // Or the adhesive force with a combustion catalyst can be improved.

The oxide layer on the channel of the microchannel reactor may be formed by coating a solution containing a metal sol, a metal powder, and an alcohol on the microchannel, followed by drying and firing.

In the above components of the oxide layer, the metal sol may be obtained by mixing a metal alkoxide and an acid in a ratio of 1: 9 to 9: 1 to obtain a metal sol, and adding metal powder and alcohol to the metal sol.

The metal alkoxide may be any one or more selected from zirconium isopropoxide, zirconium butoxide, aluminum butoxide, aluminum isopropoxide, and the like. Can be used.

The acid may be any one or more selected from nitric acid, oxalic acid and acetic acid.

The metal powder may be any one or more selected from zirconia powder, alumina powder, and titania powder.

In the above alcohol, any one or more selected from isopropyl alcohol, propanol, and butanol may be used.

After coating the oxide layer on the microchannel in the above drying may be carried out for 1 to 3 hours at 40 ~ 70 ℃, it may be baked for 1 to 3 hours at 300 ~ 400 ℃ to increase the adhesion between the oxide layer and the micro channel. .

In the microchannel reactor of the present invention, the reforming catalyst and / or the combustion catalyst may be coated on the oxide layer coated on the channel. In this case, the reforming catalyst and / or the combustion catalyst may be processed into a slurry form and coated on the oxide layer of the reforming catalyst layer and / or the combustion catalyst layer to improve the binding force between the microchannel reactor and the reforming catalyst and / or the combustion catalyst.

The slurry containing the reforming catalyst is obtained by adding a reforming catalyst to the metal sol solution and alcohol during the formation of the oxide layer, and ball-milling the coated catalyst to the oxide layer of the microchannel reactor, drying and calcining to obtain a reforming catalyst layer. Can be.

The slurry including the combustion catalyst is obtained by adding a combustion catalyst to the metal sol solution and alcohol during the formation of the oxide layer, by ball-milling, coating the oxide layer of the microchannel reactor, drying and calcining to obtain a reforming catalyst layer. Can be.

When the reforming catalyst layer and / or the combustion catalyst layer is obtained, the drying may be performed at room temperature to 70 ° C. for 5 to 10 hours, and then calcined at 350 to 400 ° C. for 1 to 3 hours.

Hereinafter, the content of the present invention will be described in detail through examples and test examples. However, these are intended to explain the present invention in more detail, and the scope of the present invention is not limited thereto.

Example 1 Reforming Catalyst Preparation and Pt / ZrO ₂ Combustion Catalyst Preparation Process

The reforming catalysts used for the reforming reaction in the micro channel reactor are commercially available Cu / ZnO / Al ₂ O ₃ (CuO 50%, ZnO 33%, Al ₂ O ₃ 8% and BET surface area = 66m ² g ^-1 ) (ICI 33 -5, manufactured by ICI, England).

As the combustion catalyst, Pt / ZrO ₂ prepared using an impregnation method was used.

In the combustion catalyst, 0.497 g of tetraammine platinum (II) nitrate is dissolved in 100 ml of distilled water as a platinum precursor, and ZrO ₂ power (BET surface area = 4.9 m ² g ^-1 , 0.25 mm in diameter) is used as a catalyst support. 5 g were added and stirred for 5 hours before evaporating the solvent using a vacuum evaporator. Thereafter, the sample was dried in an oven at 110 ° C. for 2 hours, and then fired at 500 ° C. for 2 hours to prepare a Pt / ZrO ₂ combustion catalyst.

Example 2 Oxide Layer Coating for Increasing Adhesion of Catalyst Layer

The zirconia layer was coated on the channel of the substrate as an oxide layer to increase the adhesion between the micro channel reactor and the reforming catalyst and / or the combustion catalyst.

In the above, ten channels are formed on the substrate to be coated with the reforming catalyst in the channel at 45mm × 1mm × 0.5mm (length × width × depth), and the inlet and outlet holes are formed at one side of the channel of the substrate as shown in FIG. It provided, and the thing in which the perforation was formed outside the channel was used.

In the above, 10 channels are formed on the substrate to be coated with the combustion catalyst on the channel at a length of 45 mm × 1 mm × 0.5 mm (length × width × depth), and the inlet and outlet holes are formed at one side of the channel of the substrate as shown in FIG. Was used, and a hole having a hole formed outside the channel was used.

The zirconia layer was coated with a zirconia sol solution in the channel of the substrate using a syringe (syringe), dried twice at 70 ℃ for 6 hours and then fired at 400 ℃ for 2 hours.

The zirconia sol solution preparation method is as follows.

Zirconia sol was prepared by adding HNO ₃ to the ratio of HNO ₃ : Zr to 1: 2 in Zirconium isopropoxide isopropanol complex. 0.033 g of the prepared zirconia sol was mixed with 1.33 g of zirconia powder so that the ratio of the zirconia powder and the zirconia sol was 95: 5. At this time, 10ml of isopropyl alcohol was added to adjust the viscosity. Then, zirconia powder, zirconia sol, and isopropyl alcohol were mixed with 200 µl of 1 ml of isopropyl alcohol, followed by ball milling for 12 hours to prepare a zirconia sol solution.

Example 3 Preparation and Coating of Reforming Catalyst Slurry and Combustion Catalyst Slurry

To 1 ml of the zirconia sol solution prepared in Example 2, 1 ml of isopropyl alcohol and 0.2 g of a reforming catalyst (Cu / ZnO / Al ₂ O ₃ ) were mixed and ball milled for 12 hours to prepare a reforming catalyst slurry.

The combustion catalyst slurry production method is the same as the reforming catalyst slurry production method.

To 1 ml of the zirconia sol solution prepared in Example 2, 1 ml of isopropyl alcohol and 0.2 g of the combustion catalyst (Pt / ZrO ₂ ) of Example 1 were mixed and ball milled for 12 hours to prepare a combustion catalyst slurry.

Then, the modified catalyst slurry and the combustion catalyst slurry were coated on the oxide layer coated on the channel of the substrate of Example 2 using a syringe, respectively, and dried at 70 ° C. for 6 hours, and then calcined at 400 ° C. for 2 hours. A reforming catalyst layer coated with an oxide layer and a reforming catalyst on the channel of the substrate and a combustion catalyst layer coated with the oxide layer and the combustion catalyst on the channel of the substrate were prepared.

3 (b) and 3 (c) are images in which a reforming catalyst (Cu / ZnO / Al ₂ O ₃ ) and a combustion catalyst (Pt / ZrO ₂ ) are coated on a channel of a substrate, and each catalyst coating layer is stably bonded. I could confirm that it was. Meanwhile, FIG. 3 (a) shows the channel image of the substrate not coated with the catalyst.

Example 4 Micro Channel Reactor Configuration (1)

In Example 3, a microchannel reactor including a reforming catalyst layer coated with an oxide layer and a reforming catalyst on a channel of the substrate, and a combustion catalyst layer coated with an oxide layer and a combustion catalyst on a channel of the substrate was constructed.

An upper gasket (10) having an inlet (3) into which the hydrogen-generating raw material is introduced and an outlet (4) through which water and combustion gas are discharged;

An oxide layer is coated on the channel 1 of the substrate 2, and a hydrogen generation reforming catalyst is coated on the oxide layer to promote hydrogen production from the hydrogen generating raw material, and at one end of the channel is in communication with the inlet of the upper gasket and the hydrogen generating raw material. An inlet hole 20-2 through which a gas is introduced into the channel is formed, while the other end of the channel has a discharge hole 20-3 through which the reactant of the hydrogen-producing raw material is discharged, and an outlet of the upper gasket is provided on one side of the channel. Reform catalyst layer 20 having a through-hole 20-1 in communication with,

An oxide layer is coated on the channel 1 of the substrate 2, and a combustion catalyst reacting with the combustion reactant is coated on the oxide layer, and one end of the channel has an inlet hole 30-2 through which the combustion reactant flows into the channel of the combustion catalyst layer. ) Is formed while the other end of the channel is in communication with the through hole 20-1 of the reforming catalyst layer and has a discharge hole (30-3) through which the reactants produced by the reaction of the combustion reactant and the combustion catalyst are discharged. Combustion catalyst layer 30 having a through hole (30-1) in communication with the discharge hole through which the reactant of the hydrogen-producing raw material of the reforming catalyst layer is discharged on one side of the outside,

A lower gasket 10 'having an inlet port 3' through which a combustion reactant flows and a discharge port 4 'through which a hydrogen and gas which is a reactant of a hydrogen generating raw material are discharged, which is in communication with the through hole 30-1 of the combustion catalyst layer; And a microchannel reactor having a structure as shown in FIG. 2A in which the upper gasket 10, the reforming catalyst layer 20, the combustion catalyst layer 30, and the lower gasket 10 ′ are integrally stacked.

Example 5 Micro Channel Reactor Configuration (2)

In Example 3, a microchannel reactor including a reforming catalyst layer coated with an oxide layer and a reforming catalyst on a channel of the substrate, and a combustion catalyst layer coated with an oxide layer and a combustion catalyst on a channel of the substrate was constructed.

In the microchannel reactor of Example 4, the reforming catalyst layer 20, the gas leakage preventing gasket 11, and the combustion catalyst layer 30 provided between the upper gasket 10 and the lower gasket 10 ′ may be stacked. To further perform a microchannel reactor having a structure as shown in Figure 2b.

On the other hand, the micro-channel reactor of Figure 2b is provided with a housing on the outside as shown in Figure 2c photo, it is provided with a crimping portion on one side, preferably the center of the upper portion of the micro-channel reactor can be compressed to prevent the leakage of gas. .

In the microchannel reactor of FIG. 2C, the two lower left passages are the inlets through which the hydrogen-generating raw material reacts with the reforming catalyst to discharge hydrogen and other gases, and the combustion reactants reacting with the combustion catalyst. The open passages are the inlets for methanol and water, hydrogen-producing fuels, and the outlets for the gases produced by the combustion reactants and combustion catalysts.

<Test Example 1>

The stability of the combustion catalyst bed in the micro channel reactor prepared in Example 4 of the present invention was measured.

In the microchannel reactor shown in FIG. 2A of the fourth embodiment, methanol and water are supplied as hydrogen-producing raw materials through the inlet 3 of the upper gasket 10, and at the same time, through the inlet 3 'of the lower gasket 10'. Evaporated methanol and air were supplied as combustion reactants.

The vaporized methanol and air produced carbon monoxide, carbon dioxide, and water by reaction with the combustion catalyst in the combustion catalyst layer, and the heat of reaction generated by this reaction was conducted as a heat source when hydrogen and methanol were reacted in the reforming catalyst layer through conduction. Was used.

After the combustion reactant was supplied to the inside of the microchannel reactor, the combustion reaction by the combustion catalyst was performed for 72 hours, and then a photograph of the combustion catalyst layer is shown in FIG. 4. 4A is a photograph showing the combustion catalyst layer coated on the oxide layer on the channel from above, and FIG. 4B is a photograph showing the combustion catalyst layer coated on the oxide layer on the channel in cross section.

As shown in FIGS. 4A and 4B, the combustion catalyst layer was stably present even after 72 hours of combustion reaction.

Test Example 2 Evaluation of Combustion Catalyst Bed Performance of Micro Channel Reactor

A methanol combustion experiment was performed to evaluate the combustion catalyst layer, which serves to supply a heat source to the reforming catalyst layer, for the microchannel reactor prepared in Example 4 of the present invention.

The gas composition discharged from the outlet of the combustion catalyst bed was analyzed by GC.

In the performance evaluation, the conversion of methanol was calculated by calculating the carbon balance by calculating the number of moles of carbon monoxide and carbon dioxide discharged from the exit of the combustion catalyst bed and methanol, the combustion reactant flowing into the combustion catalyst bed.

Figure 5 is a graph evaluating the temperature trend of the reactor over time. Methanol used as the combustion reactant was 0.063˜0.07 cm ³ min ⁻¹ , and oxygen, another component of the combustion reactant, was injected 1.5 times compared to methanol.

6 is a graph measuring the heat of reaction while increasing the flow rate of the reactant flowing into the combustion catalyst bed. The ratio of oxygen and methanol was 1.5 times and the combustion catalyst used was 0.066 g. It was confirmed that the conversion rate of methanol was maintained at 95% even when the flow rate of the reactant was increased, and 916Jmin ⁻¹ was obtained when the total flow rate was 300 cm ³ min ⁻¹ .

Test Example 3 Performance Evaluation of a Micro Channel Reactor Containing a Combustion Catalyst Layer

As shown in FIG. 2A mentioned in Example 4, performance evaluation of a microchannel reactor having a reforming catalyst layer and a combustion catalyst layer was performed.

The microchannel reactor shown in FIG. 2A is supplied with methanol and water as a hydrogen generating raw material through the inlet 3 of the upper gasket 10, and at the same time, vaporized as a combustion reactant through the inlet 3 'of the lower gasket 10'. Methanol and air were supplied.

7 is a graph showing the inlet and outlet temperatures of the reformed gas and the inlet and outlet temperatures of the combustion gas according to the flow rate of methanol vaporized into the combustion reactants. At this time, the ratio of oxygen and methanol in the air and the ratio of water and methanol as hydrogen-producing raw materials were fixed at 1.5, and the flow rate of vaporized methanol as the combustion reactant was 3.2 to 5.5 mlh ^-1 . It was observed that the temperature of the reactor increased linearly with the flow rate of vaporized methanol, which was a combustion reactant, and the temperature distribution at the inlet and outlet was about 6 ° C.

8 is a graph showing the conversion of methanol as a hydrogen generating raw material according to the reaction temperature. The flow rate of methanol was 1.65 mlh ^-1 and the ratio of water and methanol was adjusted to 1.5. As the reaction temperature was increased, the activity of the methanol reforming reaction was increased, and conversion of more than 97% of methanol to hydrogen was obtained at 250 ° C.

9 is a graph showing the concentration of the reformed gas outlet and the hydrogen production rate. In the experimental conditions, the flow rate of methanol, which is a hydrogen generating raw material, was 1.65 mlh ⁻¹ , and the ratio of water and methanol was adjusted to 1.5. It was confirmed that the gas composition on the outlet side was 80% hydrogen, 21-22% carbon dioxide, and 1-1.5% carbon monoxide, and a maximum hydrogen yield of 1.9 lh ⁻¹ was obtained.

10 is a graph evaluating the reactivity by increasing the amount of methanol to be reformed while maintaining the reforming reaction temperature at 270 ℃. The flow rate of methanol was varied from 1.65 to 3.65 ml ^-1 and the ratio of water and methanol was fixed at 1.5. As the amount of methanol increased, the conversion decreased, but the methanol conversion of 80% or more was obtained even at 3.65 ml ⁻¹ , and the hydrogen production at that time was found to be 3.9 ^l h ⁻¹ .

As described above, the present invention has been described with reference to the preferred embodiments and test examples, but a person skilled in the art may vary the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be understood that modifications and changes can be made.

In the microchannel reactor of the present invention, a stable catalyst coating layer was obtained by coating an oxide layer on the channel and coating a reforming catalyst and a combustion catalyst on the oxide layer. In addition, it was confirmed that the catalyst layer was stably coated even when the reactor was operated for a long time.

On the other hand, the microchannel reactor of the present invention is coated with an oxide layer on the channel, and the reforming catalyst and the combustion catalyst are coated on the oxide layer to evaluate the performance of the microchannel reactor including the reforming catalyst layer and the combustion catalyst layer. Can be applied directly to the hydrogen production of portable fuel cells by supplying directly from the combustion catalyst bed without an external electrical heat source.

Claims (12)

An upper gasket having an inlet for introducing hydrogen-producing raw materials and an outlet for discharging water and combustion gas; An oxide layer is coated on the channel of the substrate, and a hydrogen generation reforming catalyst is coated on the oxide layer to promote hydrogen production from the hydrogen generating raw material, and at one end of the channel is in communication with the inlet of the upper gasket and the hydrogen generating raw material is introduced into the channel. A reformed catalyst layer having a hole formed thereon and the other end of the channel having a discharge hole through which the reactant of the hydrogen-producing raw material is discharged, and having a through hole communicating with an outlet of the upper gasket on one side outside the channel; An oxide layer is coated on the channel of the substrate, and a combustion catalyst reacting with the combustion reactant is coated on the oxide layer, and one end of the channel forms an inlet hole through which the combustion reactant enters the channel of the combustion catalyst layer, while the other end of the channel is It is in communication with the through-holes of the reforming catalyst layer and has a discharge hole for discharging the reactants produced by the reaction of the combustion reactant and the combustion catalyst, and in communication with the discharge hole for discharging the reactants of the hydrogen-producing raw material of the reforming catalyst layer on one side outside the channel Combustion catalyst layer having a through hole, A lower gasket having an inlet through which a combustion reactant is introduced and an outlet through which the hydrogen and gas, which is a reactant of a hydrogen generating raw material, is discharged in communication with the through hole of the combustion catalyst layer, wherein the upper gasket, the reforming catalyst layer, the combustion catalyst layer and the lower gasket A micro channel reactor containing this integrally stacked combustion catalyst layer. The method of claim 1, wherein the oxide layer comprises a methanol combustion catalyst layer, characterized in that formed by coating a solution containing a metal sol, metal powder, alcohol on top of the micro-channel, dried and calcined Micro channel reactor. The micro-channel reactor according to claim 1, wherein the hydrogen evolution reforming catalyst is formed by coating a slurry including the hydrogen evolution reforming catalyst on the oxide layer, drying and calcining. The micro-channel reactor according to claim 1, wherein the combustion catalyst is formed by coating a slurry including the combustion catalyst on the oxide layer, drying and calcining. The methanol combustion catalyst layer as claimed in claim 1, wherein the reaction flow pattern between the hydrogen-generating raw material and the reforming catalyst and the reaction flow pattern between the combustion reactant and the combustion catalyst are in a counter flow pattern that is opposite to each other. Micro channel reactor containing. 2. The micro-containing methanol combustion catalyst layer according to claim 1, wherein the reformed catalyst layer and the combustion catalyst layer are stacked in a pair, and a plurality of the reformed catalyst layer and the combustion catalyst layer are stacked between the upper gasket and the lower gasket. Channel reactor. The microchannel reactor of claim 1, wherein the hydrogen-generating feedstock is methanol and water. The microchannel reactor of claim 1, wherein the combustion reactants are vaporized methanol and air. The method of claim 2, wherein the oxide layer is a metal sol solution, zirconia powder, alumina powder, a solution containing any one or more metal powder selected from any one or more selected from at least one selected from the titania powder and at least one alcohol selected from isopropyl alcohol, propanol, butanol A microchannel reactor containing a methanol combustion catalyst layer, characterized in that it is formed by coating on top of the microchannel, drying and firing. The reforming catalyst of claim 3, wherein the reforming catalyst comprises at least one alcohol selected from a metal sol solution, isopropyl alcohol, propanol, butanol, Cu / ZnO / Al ₂ O ₃ , Ni / Al ₂ O ₃ , Pd / Al ₂ O on the oxide layer. ₃ , Ph / Al ₂ O _{3 It} is formed by coating a slurry mixed with at least one selected from, and dried for 5 to 10 hours at room temperature to 70 ℃ and then calcined at 350 to 400 ℃ for 1 to 3 hours Micro channel reactor containing a methanol combustion catalyst bed. The method of claim 3, wherein the combustion catalyst is any one or more alcohol selected from a metal sol solution, isopropyl alcohol, propanol, butanol, Pt / ZrO ₂ , Pt / Al ₂ O ₃ , Pd / Al ₂ O ₃ , Pt / A slurry containing a methanol combustion catalyst layer is formed by coating a slurry mixed with at least one selected from CeO ₂ and drying at room temperature to 70 ° C. for 5 to 10 hours, and then calcining at 350 to 400 ° C. for 1 to 3 hours. Micro channel reactor. The metal sol solution of claim 9, wherein the metal sol solution comprises at least one metal alkoxide selected from zirconium isopropoxide, zirconium butoxide, aluminum butoxide, and aluminum isopropoxide. And at least one acid selected from nitric acid, oxalic acid and acetic acid is mixed in a ratio of 1: 9 to 9: 1.

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