JP2005185890A - Catalyst and process for producing hydrogen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst for producing a hydrogen containing gas excellent in hydrogen forming rate even at a low temperature. <P>SOLUTION: The catalyst for producing the hydrogen containing gas includes a reforming catalyst for forming hydrogen and carbon monoxide from a hydrocarbon in the presence of water and/or oxygen, and a shift catalyst for reacting carbon monoxide contained in the reformed gas with water to form hydrogen in the same casing. Since the catalyst remarkably enhances a hydrogen yield even at a low temperature and can simultaneously suppress methanation consuming hydrogen, hydrogen productivity is high. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hydrogen production catalyst, and more particularly to a hydrogen catalyst including a reforming catalyst and a shift catalyst in the same casing, and a hydrogen production method using the catalyst.

  In recent years, in response to social demands and trends against the background of energy and environmental issues, polymer electrolyte fuel cells that can operate at room temperature and obtain high output density have attracted attention as power sources for electric vehicles and stationary power sources. . As a hydrogen source of such a polymer electrolyte fuel cell, in addition to a system using pure hydrogen, hydrogen from hydrocarbons and alcohols such as methane, methanol, LP gas, city gas, natural gas, light oil, kerosene, etc. There is also a method of taking out and using. In order to generate hydrogen using hydrocarbon as a raw material, it is common to perform a reforming reaction, a shift reaction, and a CO removal reaction.

  Here, in the reforming reaction of methane, it is considered that the oxidation and steam reforming reaction represented by the following formula proceed in parallel by a hydrocarbon such as methane, oxygen, and steam.

As shown by the above formula, CO is by-produced in the reformed gas, and this CO acts as a catalyst poison of the platinum-based catalyst used for the electrode of the fuel cell. For this reason, it is necessary to convert this CO into CO ₂ that is harmless to the platinum electrode catalyst, and the so-called shift reaction shown below is used to reduce the CO concentration contained in the reformed gas to about 1% by volume. .

However, since a small amount of CO remains even after the shift reaction, CO is further converted to CO ₂ using a CO selective oxidation catalyst such as alumina supporting a noble metal, and this is the CO removal reaction following the shift reaction. .

  Various catalysts exist for the above-described reforming reaction. For example, one type selected from the group consisting of titanium, aluminum, silicon, zirconium, nickel, iron, cobalt, copper, zinc, platinum, palladium, ruthenium, and rhodium. There is a hydrocarbon reforming catalyst in which the above catalyst is used as a catalyst component and this is coated on a metal honeycomb monolith support (Patent Document 1). In the patent document, the above-mentioned catalyst component is coated on the honeycomb monolith support because water or oxygen is supplied to the hydrocarbon and reformed through a catalytic reaction to obtain hydrogen, both of which cause heating or heat generation. This is because a honeycomb monolith support having many voids is used to facilitate control of heat transfer. As the reforming catalyst, a catalyst in which the catalyst component is supported on the honeycomb monolith carrier as in the above-mentioned document 1 is used, but the present invention is not limited to this, and the catalyst component is supported in alumina or the like to form particles. The prepared catalyst can be used by filling the reforming reaction layer.

In such a hydrocarbon reforming reaction for the purpose of producing hydrogen for fuel cells, the reaction temperature is set to a high temperature of 600 ° C. or higher to obtain high activity and suppress the production of carbon monoxide (Patent Document 2). ), High reforming reaction at a lower temperature is required in consideration of starting / stopping stability when used for a moving body such as an automobile.
JP 2000-126595 A JP 2002-104809 A

  As described above, hydrogen gas and CO are generated when partial oxidation is performed using hydrocarbon as fuel. In this case, when the reforming temperature is lowered to 500 ° C. or lower, the amount of carbon monoxide produced can be balanced and suppressed, but the hydrogen concentration decreases and methane further increases. For this reason, hydrogen cannot be produced in a high yield, and particularly when used in an automobile or the like, the hydrogen supply capability at the time of startup is extremely lowered.

  In view of the above situation, the present invention has an object to provide a catalyst capable of producing hydrogen at a low temperature and in a high yield when producing hydrogen using a hydrocarbon as a raw material.

  The present invention also provides a method for producing hydrogen using such a catalyst.

  As a result of detailed examination of the reforming catalyst and the shift catalyst in order to achieve the above object, the low methane reforming at 400 to 550 ° C. does not reduce the amount of methane because of the methanation reaction shown below. As a result of the reaction, it was found that methane was produced.

  In order to suppress methanation and reduce carbon monoxide, it is considered effective to promote the shift reaction between carbon monoxide and water as described above. Even if hydrogen is generated, the methanation cannot actually be suppressed because of equilibrium restrictions. Therefore, hydrogen is consumed by this methanation, and the hydrogen production rate is lowered, resulting in lack of startability at low temperatures.

  Surprisingly, however, the reforming reaction and the shift reaction were carried out under the reforming catalyst conditions at a low temperature of 350 to 550 ° C. using the conventional honeycomb carrier or the catalyst-filled reforming catalyst and the shift catalyst. The hydrogen yield was significantly improved and at the same time the methanation could be suppressed. The present invention has been completed based on the above findings.

  According to the hydrogen-containing gas production catalyst of the present invention, hydrogen can be efficiently produced at a low temperature. For this reason, even when mounted on an automobile or the like, a hydrogen generator excellent in startability can be configured.

  The hydrogen-containing gas production catalyst of the present invention can be prepared by using a reforming catalyst and a shift catalyst and housed in the same casing, and the production of the catalyst itself is easy.

  When the hydrogen-containing gas production catalyst of the present invention is used, hydrogen can be efficiently produced by supplying a raw material gas and reacting under the same conditions, so that the production process can be simplified.

  According to the present invention, a high-concentration hydrogen-containing reformed gas can be produced, which is suitable as a reforming reaction device for a fuel cell such as an automobile having a small mounting volume.

  In the first aspect of the present invention, a reforming catalyst that generates hydrogen and carbon monoxide from hydrocarbons in the presence of water and / or oxygen, and carbon monoxide contained in the reformed gas react with water to generate hydrogen. This is a hydrogen-containing gas production catalyst that includes a shift catalyst that generates hydrogen in the same housing.

  As an aspect in which the reforming catalyst and the shift catalyst are included in the same casing, there is (1) a method of supporting the reforming catalyst and the shift catalyst on a honeycomb carrier, and more specifically, (2) a honeycomb carrier. A method of stacking and supporting the reforming catalyst layer and the shift catalyst layer (see FIGS. 1 and 2), and (3) supporting a mixture of the reforming catalyst layer and the shift catalyst layer on a honeycomb carrier. (4) A method of supporting the reforming catalyst layer and the shift catalyst layer on the honeycomb carrier separately from upstream and downstream of hydrocarbon gas, (5) The reforming The catalyst is a catalyst carrier having a catalyst component supported on a honeycomb carrier, and the shift catalyst is a honeycomb carrier having a catalyst component supported thereon, and the honeycomb-supported reforming catalyst and the honeycomb-supported shift catalyst are disposed in the same casing. (See FIGS. 4 and 5) 6) A method in which the reforming catalyst layer and the shift catalyst layer are supported on the honeycomb carrier in parallel with the gas flow from the upstream to the downstream of the hydrocarbon gas (see FIG. 6), and other cells of the honeycomb carrier are configured. For example, the reforming catalyst and the shift catalyst may be alternately supported on the partition wall (see FIG. 7).

  When the honeycomb carrier is not used, (1) the reforming catalyst and the shift catalyst are formed into a granular shape, and the granular reforming catalyst and the granular shift catalyst are filled in the same casing (FIG. 8). (Refer to Fig. 9) (3) Laminating the reforming catalyst component and the shift catalyst component on the granular carrier. It can also be performed by the method (FIGS. 10 and 11).

  A feature of the present invention is that a reforming catalyst and a shift catalyst are included in the same housing, and a conventionally known catalyst can be used as such a reforming catalyst or shift catalyst. Preferably, as the reforming catalyst used in the present invention, a catalyst in which a support is supported with a noble metal as an active metal (hereinafter referred to as “catalyst component”) is prepared in a slurry form, and this is prepared as a honeycomb support. It is carried on. In addition, although partial oxidation reforming, steam reforming, and autothermal reforming are known as reforming, any of them may be used in the present invention.

As the noble metal, there is one obtained by supporting and firing at least one noble metal element selected from platinum, rhodium, palladium and ruthenium, particularly preferably rhodium. Such a noble metal element is excellent in a steam reforming reaction (for example, CH ₄ + H ₂ O → CO + 3H ₂ ), and rhodium is particularly preferable because it is excellent in durability and catalytic activity.

  The amount of the noble metal element supported is 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, in terms of element, per reforming catalyst component. Within this range, the dispersibility of the noble metal element on the carrier is excellent, and as a result, high catalytic activity can be ensured.

  As the catalyst carrier for supporting the noble metal, aluminum oxide, zirconium oxide, titanium oxide, silicon oxide, cerium oxide, cerium-zirconium composite oxide and the like can be used, preferably aluminum oxide, zirconium oxide and / or Titanium oxide.

  The loading of the noble metal on the alumina oxide can be prepared by using various known techniques such as an impregnation method, a coprecipitation method, and a competitive adsorption method using a catalyst preparation solution containing a noble metal element. The treatment conditions can be appropriately selected according to various methods. Usually, the support is brought into contact with the catalyst preparation solution at 20 to 70 ° C. for 0.5 to 20 hours. For example, a catalyst preparation solution in which a compound containing the noble metal element is dissolved or dispersed may be used to impregnate the carrier, and then dried and fired to obtain a fired product. As such a solution, water, alcohols such as methanol and ethanol, ethers such as diethyl ether, carboxylic acids, general organic solvents, and the like, which can dissolve a compound containing the above elements, can be widely used. .

  Thereafter, the catalyst-supported carrier is dried. As a drying method, for example, natural drying, evaporation to dryness, rotary evaporator, spray dryer, drying with a drum dryer, or the like can be used. After applying these means, firing is performed. The firing temperature is 300 to 600 ° C., and the firing time is 30 to 600 minutes.

In this invention, you may carry | support the at least 1 sort (s) of element chosen from manganese, iron, cobalt, nickel, zinc, chromium, or copper with a noble metal. This is because the addition of these improves the H ₂ production rate. These additional components may be carried out simultaneously with the loading of the noble metal element or may be loaded separately. In order to carry the noble metal element separately, the carrier carrying the additive component may be impregnated in a solvent in which a compound containing the noble metal element is dissolved or dispersed, and then fired. In addition to the impregnation method, various known techniques such as a coprecipitation method and a competitive adsorption method can be used.

  On the other hand, the shift catalyst that can be preferably used in the present invention may be any shift catalyst as long as it can catalyze the shift reaction represented by the following formula. However, the present invention includes at least one element selected from the group consisting of titanium, zirconium, vanadium, niobium and tantalum, cerium element, platinum, rhodium, palladium, ruthenium, iridium and osmium. A shift catalyst is preferred. The shift catalyst used in the present invention is not limited to a honeycomb shape but may be granular. In the case of a honeycomb shape, the shift catalyst can be produced by supporting the following catalyst components on a honeycomb monolith.

The shift catalyst of the present invention preferably contains at least one element selected from platinum, rhodium, palladium, ruthenium, iridium and osmium. More preferred is platinum. This is because the ability to oxidize CO and convert it to CO ₂ is excellent. Furthermore, it is good to contain a cerium element. This is because cerium is excellent in oxygen carrying ability. The content of cerium is preferably 5 mol% or more in the shift catalyst component, more preferably 10 to 90 mol%, and particularly preferably 20 to 80 mol%. In addition to platinum, at least one element selected from the group consisting of titanium, zirconium, vanadium, niobium, and tantalum may be included. This is because it is effective as an active species that can extract H ₂ from H ₂ O.

  As described above, at least one element selected from titanium, zirconium, vanadium, niobium, tantalum, cerium, platinum, rhodium, palladium, ruthenium, iridium and osmium can be used as the shift catalyst used in the present invention. The source of such elements is not particularly limited, and compounds containing these elements can be used widely. Such compounds include nitrates, sulfates, ammonium salts, amines, carbonates, bicarbonates, halogen salts, nitrites, inorganic salts such as oxalic acid, carboxylates and hydroxides such as formate, Examples include alkoxides and oxides, which can be appropriately selected depending on the type and pH of the solvent in which these are dissolved. Among these, nitrates, carbonates, oxides, hydroxides and the like are preferable for industrial use.

  Regarding elements selected from platinum, rhodium, palladium, ruthenium, iridium and osmium (hereinafter also referred to as platinum group elements), dinitrodiamine platinum, platinum chloride, etc. can be used as platinum raw materials. preferable. It is because it is excellent in dispersibility. Similarly, rhodium, palladium, ruthenium, iridium and osmium are preferably nitrates, ammonium salts and the like. The compounding amount of these elements is preferably 0.01 to 20.0% by mass, more preferably 1.0 to 20.0% by mass, and particularly preferably 10.2% by mass in the shift catalyst component in terms of mass. It is 0-15.0 mass%. If it is less than 0.01% by mass, the CO conversion may not be sufficient. These elements are considered to be active components of the catalyst, and it is preferable to distribute these so-called platinum group elements on the catalyst surface in order to improve the CO conversion. This is because the contact rate with CO is improved even at low temperatures, and the CO conversion rate is improved.

  When an element selected from the group consisting of titanium, zirconium, vanadium, niobium and tantalum is contained, it is preferably 5 mol% or more, more preferably 10 to 90 mol in the shift catalyst component in terms of element. %, Particularly preferably 20 to 80 mol%. In addition, when using together 2 or more types of elements, it calculates with the total amount.

  The shift catalyst used in the present invention may further contain an aluminum element and / or a silicon element. Examples of aluminum compounds that supply these elements include aluminum oxides such as α-alumina, β-alumina, and γ-alumina, aluminum hydroxides such as gibbsite and boehmite, and aluminum salts such as aluminum nitrate and aluminum sulfate. In addition, an aluminum compound that becomes an oxide by firing can be used. In particular, colloidal alumina such as alumina sol is preferably used. Similarly, as the silicon compound, in addition to colloidal silica, covalently bonded compounds such as silicon oxide, silicon nitride, silicon carbide, silane, silicon sulfide, etc .: sodium silicate, ammonium silicate, sodium aluminosilicate, ammonium aluminosilicate, phosphorous silicate Silicates containing sodium silicates such as sodium phosphate, ammonium phosphosilicate, and silica containing silicon such as feldspar: and silica mixtures can be used. In addition to the above, silica-alumina, and clay minerals such as mullite and zeolite can be used as the aluminum compound and silicon compound. The content of these is suitably 0.1 to 50.0% by mass in the catalyst component. High heat resistance can be expected by adding a large amount, but it is preferable that a large amount exist, and the abundance ratio of at least one element selected from the group consisting of cerium, titanium, zirconium, vanadium, niobium, and tantalum decreases, In some cases, the catalytic action does not necessarily produce a favorable result.

  There is no restriction | limiting in particular as a method of preparing the said shift catalyst, It can manufacture with a general catalyst preparation method. For example, a method in which a composite containing a compound other than the platinum group element is previously formed, dried and fired, and then the platinum group element is supported on the fired product can be employed.

  The catalyst is preferably supported on a honeycomb monolith. This is because it is easy to fill the catalyst in the catalyst filling portion of the reformer and the air permeability of the raw material gas and the reformed gas can be secured by the honeycomb structure. Further, when the raw material gas is supplied, the catalyst can be prevented from being heated and calcined, and the catalyst life and the catalytic activity can be improved.

  As a material constituting the honeycomb monolith carrying the reforming catalyst component and the shift catalyst component, ceramic honeycomb (ceramics, 400 cells to 3000 cells, diameter 35 mmφ), metal foam (Ni-Cr, 20 pores / inch to 50 pores / inch, 100 mmφ) and / or ceramic foam (ceramics, 9 pores / inch to 30 pores / inch, diameter 75 mmφ) and the like may be used. Cera honeycomb, metal foam, and Cera foam are preferable because they are excellent in pressure loss and easy in coating technology.

  The catalyst is supported on the honeycomb monolith by preliminarily stirring and pulverizing the catalyst component with 1 to 10 times water to prepare a catalyst slurry, which is applied to the honeycomb monolith, and dried and fired. Can be manufactured.

  At this time, as shown in FIG. 1, in order to stack the reforming catalyst and the shift catalyst on the honeycomb carrier, the reforming catalyst slurry is prepared in advance, applied to the honeycomb monolith carrier, dried and fired, and then shifted. What is necessary is just to carry | support a catalyst slurry. By arranging in this way, the CO produced by the lower reforming catalyst can come into contact with the shift catalyst before being released into the space, and the reaction can proceed extremely advantageously. . As a mode of lamination, as shown in FIG. 2, a shift catalyst may be applied to a honeycomb carrier, dried and fired, and then the reforming catalyst may be supported on the shift catalyst layer.

  Further, as shown in FIG. 3, in order to mix the reforming catalyst and the shift catalyst and carry them on the honeycomb catalyst, it is only necessary to prepare a mixture slurry of the two, apply it to the honeycomb carrier, dry it, and fire it. As a result, as shown in FIG. 12, the catalyst coat layer in which the reforming catalyst particles and the shift catalyst particles are mixed is supported. Note that the mixture of the reforming catalyst and the shift catalyst is not limited to the above-described embodiment, and for example, a support in which the reforming catalyst component and the shift catalyst component are supported on the same support (inert particles) is supported on the honeycomb support. You may let them. This aspect is shown in FIG. When the reforming catalyst and the shift catalyst are mixed as shown in FIG. 12, the mixed state of the reforming catalyst component and the shift catalyst component may become uneven, but as shown in FIG. When the catalyst component and the shift catalyst component are supported, such non-uniformity due to the course of use can be reduced, which is more preferable.

  In addition, as shown in FIG. 4, a monolith type reforming catalyst in which a reforming catalyst is supported on a honeycomb carrier and a monolith type shift catalyst in which a shift catalyst is supported on the honeycomb carrier from the upstream side to the downstream side of the gas flow. It may be placed in the body. In FIG. 4, the reforming catalyst is arranged upstream, but the order of the shift catalyst and the reforming catalyst may be arranged upstream, and the shift catalyst may be upstream as shown in FIG. 5. . 4 and 5 show a mode in which the reforming catalyst and the shift catalyst are supported on different honeycomb carriers, but the shift catalyst and the shift catalyst are modified separately on the upstream side and the downstream side of the gas flow using the same honeycomb carrier. A quality catalyst may be supported.

  Further, as shown in FIG. 6, a reforming catalyst and a shift catalyst may be supported in parallel with the gas flow. In FIG. 6, when the cross section of the honeycomb carrier is divided into four parts, the reforming catalyst and the shift catalyst are alternately supported. However, it is not limited to four parts, and the degree of division is increased more than eight parts, twelve parts, etc. Also good. In order to prepare such a carrier, for example, masking is performed on the side that is not desired to be supported. Further, as shown in FIG. 7, the cells of the honeycomb may be alternately loaded with the reforming catalyst and the shift catalyst. For preparing such a carrier, for example, masking is performed on the side that is not desired to be carried.

  On the other hand, as a mode in which the casing is filled with the reforming catalyst and the shift catalyst, the honeycomb monolith is not used, the reforming catalyst and the shift catalyst are molded into a granular shape, and the granular reforming catalyst and the granular shift catalyst are the same. The housing may be filled (see FIG. 8). It is preferable that the reforming catalyst and the shift catalyst are uniformly mixed in that CO is removed by the shift reaction immediately after the reforming reaction.

  On the other hand, in the present invention, as shown in FIG. 9, a reforming catalyst component and a shift catalyst component may be supported on the same carrier and filled with such a catalyst. This is because when such a catalyst is used, nonuniformity between the reforming catalyst component and the shift catalyst component does not occur even when used for a long time.

  Specifically, as the reforming catalyst component, at least one kind of noble metal element selected from at least platinum, rhodium, palladium and ruthenium, and at least one kind selected from manganese, iron, cobalt, nickel, zinc, chromium, or copper. And at least one element selected from the group consisting of titanium, zirconium, vanadium, niobium and tantalum, and at least one element selected from platinum, rhodium, palladium, ruthenium, iridium and osmium, which are shift catalyst components, and It can be prepared by supporting cerium on a support such as alumina. The preferable range of each component in this case can be calculated according to the above-described reforming catalyst component and shift catalyst component.

  In the present invention, the reforming catalyst component and the shift catalyst component may be laminated on the same carrier. In FIG. 10, the reforming catalyst component is laminated on the lower layer and the shift catalyst component is laminated on the upper layer. However, as shown in FIG. 11, the reforming catalyst component may be laminated on the upper layer and the shift catalyst component may be laminated on the lower layer.

  In the hydrogen-containing gas production catalyst of the present invention, the reforming catalyst and the shift catalyst are supported on the honeycomb carrier so that the amount of the reforming catalyst and the shift catalyst is 10 to 1000 parts by mass with respect to 100 parts by mass of the reforming catalyst component. Is more preferable, and it is 50-200 mass parts more preferably. Moreover, the platinum content per unit volume of the hydrogen-containing gas production catalyst is 0.1 to 20 g / L regardless of whether it is a honeycomb shape or a catalyst-filled type. Similarly, the rhodium content per unit volume of the hydrogen-containing gas production catalyst is 0.1 to 20 g / L. This is because the hydrogen production efficiency at a low temperature is excellent within this range.

  A second aspect of the present invention is a method for producing hydrogen, characterized in that hydrocarbon is supplied to the hydrogen-containing gas production catalyst and the reaction is carried out while controlling the temperature in the catalyst layer at 350 to 550 ° C.

The feed gas supplied to the reforming catalyst of the present invention is a hydrocarbon having 1 to 20 carbon atoms, such as methane, ethane, propane, butane, isobutane, pentane, isopentane, hexane, isohexane, octane, isooctane, nonane, Examples include isononane, decane, and isodecane. It is preferable that the hydrocarbon concentration at the time of supplying to the reformer is 1 to 10% by volume, more preferably 1 to 5% by volume. The supply amount of the raw material gas is 2,000 to 200,000 h ⁻¹ for GHSV with respect to the catalyst filling portion.

  Further, the oxygen supply amount is preferably controlled such that the oxygen / hydrocarbon carbon ratio is 0.1 to 1.5, preferably 0.5 to 1.5. Similarly, the amount of water supplied is a water / hydrocarbon carbon ratio of 1 to 3.

  The hydrogen-containing gas production catalyst of the present invention can be reacted under the above conditions by controlling the temperature in the catalyst layer at 350 to 550 ° C, more preferably 450 to 550 ° C. Although it is at a lower temperature than the conventional reforming reaction, by using the hydrogen-containing gas production catalyst of the present invention, methanation can be efficiently suppressed and high concentration hydrogen can be produced. For this reason, it can be used effectively even in an automobile or the like whose mounting range is limited.

  Hereinafter, the present invention will be described by way of examples.

  The method for preparing the reforming catalyst used in the present invention is as follows.

(Example 1)
To 100 g of rhodium alumina catalyst in which rhodium equivalent to 5% by mass is supported on aluminum oxide powder, alumina sol equivalent to 10 g in weight after calcination and water are added and dispersed and emulsified for 3 hours to give a reforming catalyst slurry. Got. This catalyst slurry was applied to a 100-ml cordierite honeycomb monolith of 400 cells, dried and fired so that the upper and lower ends of the catalyst were uniform, and the catalyst coat layer was made uniform.

  Thereafter, 100 g of platinum ceria catalyst on which platinum corresponding to 5% by mass is supported on cerium oxide powder is added with alumina sol and water equivalent to 10 g in terms of weight after calcination, and dispersed, emulsified and shifted for 3 hours. A catalyst slurry was obtained. The catalyst slurry was applied to the above cordierite honeycomb monolith, dried and fired so that the upper and lower ends of the catalyst were uniform, and the honeycomb monolith shown in FIG. 1 in which the reforming catalyst was applied to the lower layer of the shift catalyst was obtained. .

(Example 2)
To 100 g of platinum ceria catalyst on which platinum equivalent to 5 mass% is supported on cerium oxide powder, alumina sol equivalent to 10 g in weight after calcination and water are added and dispersed and emulsified for 3 hours to give a reforming catalyst slurry. Got. The catalyst slurry was applied to a 400-ml 100 ml cordierite honeycomb monolith, and then dried and fired so that the upper and lower ends of the catalyst were uniform to obtain a uniform catalyst coat layer.

  Next, a shift catalyst slurry obtained by dispersing and emulsifying for 3 hours by adding alumina sol and water corresponding to 10 g in terms of weight after calcination to 100 g of rhodium alumina catalyst in which rhodium corresponding to 5 mass% is supported on aluminum oxide powder. Got. The catalyst slurry was applied to the honeycomb monolith, dried and fired so that the upper and lower ends of the catalyst were uniform, and the catalyst of the embodiment shown in FIG. 2 in which the shift catalyst was applied to the lower layer of the reforming catalyst was obtained.

(Example 3)
50 g of rhodium alumina catalyst in which rhodium corresponding to 5% by mass is supported on aluminum oxide powder is mixed with 50 g of platinum ceria catalyst in which platinum corresponding to 5% by mass is supported on cerium oxide powder. Thereafter, alumina sol corresponding to 10 g in weight and water were added and dispersed and emulsified for 3 hours to obtain a mixed catalyst slurry of a reforming catalyst and a shift catalyst. The catalyst slurry was applied to a 100-ml cordierite honeycomb monolith of 400 cells, dried and fired so that the upper and lower ends of the catalyst were uniform, and the catalyst of the embodiment shown in FIG. 3 was obtained.

Example 4
A reforming catalyst obtained by carrying the same amount of the reforming catalyst slurry obtained in Example 1 on the monolith used in Example 1 as in Example 1, and a monolith using the shift catalyst slurry obtained in Example 1 in Example 1 4 was used in the same manner as in Example 1 and the reforming catalyst was disposed upstream of the shift catalyst, whereby a catalyst having the mode shown in FIG. 4 was obtained.

(Example 5)
A reforming catalyst obtained by carrying the same amount of the reforming catalyst slurry obtained in Example 1 on the monolith used in Example 1 as in Example 1, and a monolith using the shift catalyst slurry obtained in Example 1 in Example 1 The shift catalyst supported in the same amount as in Example 1 was used, and the shift catalyst was disposed on the upstream side of the reforming catalyst to obtain a catalyst having the mode shown in FIG.

(Examples 6 and 7)
To 100 g of rhodium alumina catalyst in which rhodium equivalent to 5% by mass is supported on aluminum oxide powder, alumina sol equivalent to 10 g in weight after calcination and water are added and dispersed and emulsified for 3 hours to give a reforming catalyst slurry. Got. The catalyst slurry was applied to a 400-cell 100 ml cordierite honeycomb monolith partially masked in advance with the shift catalyst phase of FIG. 6 and dried and fired so that the upper and lower ends of the catalyst were uniform. The masking was then removed and the coated part was masked again.

  Thereafter, 100 g of platinum ceria catalyst on which platinum corresponding to 5% by mass is supported on cerium oxide powder is added and dispersed and emulsified by adding alumina sol and water equivalent to 10 g in weight after calcination for 3 hours. A catalyst slurry was obtained. The catalyst slurry was applied to the previous cordierite honeycomb monolith, dried and fired so that the upper and lower ends of the catalyst were uniform, and the previous masking was removed. Thus, a catalyst having the embodiment shown in FIG. 6 was obtained. Moreover, the catalyst of the form shown in FIG. 7 was obtained by changing a masking part into the reforming catalyst part and shift catalyst part which are shown in FIG.

(Example 8)
The support is coated with the shift catalyst slurry used in Example 1 to prepare granules, and similarly, a granular reforming catalyst is prepared from the reforming catalyst slurry used in Example 1, and each granular reforming catalyst and shift catalyst are prepared. And the catalyst layer was filled into a catalyst layer to obtain a catalyst having an embodiment shown in FIG.

Example 9
The reforming catalyst slurry and shift catalyst slurry used in Example 1 were simultaneously coated on the support to obtain a catalyst having the form shown in FIG.

(Example 10)
The reforming catalyst slurry used in Example 1 was applied on the catalyst carrier, and then the shift catalyst slurry was applied to obtain the form shown in FIG.

(Example 11)
The shift catalyst slurry used in Example 1 was applied on the catalyst carrier, and then the reforming catalyst slurry was applied to obtain the catalyst having the mode shown in FIG.

FIG. 3 is a diagram showing an example of a preferred embodiment of the present invention, in which a reforming catalyst (lower layer) and a shift catalyst (upper layer) are stacked on a honeycomb catalyst. FIG. 3 is a view showing an example of a preferred embodiment of the present invention, in which a reforming catalyst (upper layer) and a shift catalyst (lower layer) are stacked on a honeycomb catalyst. FIG. 3 is a view showing an example of a preferred embodiment of the present invention, in which a honeycomb catalyst is loaded with a mixture layer of a reforming catalyst and a shift catalyst. FIG. 3 is a view showing an example of a preferred embodiment of the present invention, in which a reforming catalyst layer is disposed upstream of a honeycomb catalyst and a shift catalyst layer is disposed downstream. It is an example of a preferred embodiment of the present invention, and is a view showing an embodiment in which a shift catalyst layer is disposed upstream of a honeycomb catalyst and a reforming catalyst layer is disposed downstream. It is an example of a preferred embodiment of the present invention, and is a view showing an embodiment in which a shift catalyst layer and a reforming catalyst layer are divided and arranged in parallel with the gas flow of the honeycomb catalyst. FIG. 3 is a view showing an example of a preferred embodiment of the present invention, in which a shift catalyst layer and a reforming catalyst layer are alternately supported in each cell in parallel with a gas flow of a honeycomb catalyst. It is a figure which is an example of the preferable aspect of this invention, Comprising: The aspect which mixed and filled the housing | casing with the granular shift catalyst and the granular reforming catalyst. It is a figure which shows the catalyst which carry | supported the shift catalyst component and the reforming catalyst component on the same support | carrier. It is a figure which shows the catalyst which laminated | stacked the shift catalyst component (upper layer) and the reforming catalyst component (lower layer) on the same support | carrier. It is a figure which shows the catalyst which laminated | stacked the shift catalyst component (lower layer) and the reforming catalyst component (upper layer) on the same support | carrier. It is a figure which shows typically the mixed state at the time of mixing and supporting the shift catalyst and the reforming catalyst on the honeycomb catalyst. It is a figure which shows the state which carry | supported the catalyst which carry | supported the shift catalyst component and the reforming catalyst component on the same support | carrier in the honeycomb catalyst.

Claims (15)

  A reforming catalyst that generates hydrogen and carbon monoxide from hydrocarbons in the presence of water and / or oxygen, and a shift catalyst that generates hydrogen by reacting carbon monoxide contained in the reformed gas with water. Hydrogen-containing gas production catalyst in the same housing.   The hydrogen-containing gas production catalyst according to claim 1, wherein the hydrogen-containing gas production catalyst is a honeycomb carrier on which the reforming catalyst and the shift catalyst are supported.   The hydrogen-containing gas production catalyst according to claim 2, wherein the reforming catalyst layer and the shift catalyst layer are stacked and supported on the honeycomb carrier.   The hydrogen-containing gas production catalyst according to claim 2, wherein a mixture of the reforming catalyst layer and the shift catalyst layer is supported on the honeycomb carrier.   The hydrogen-containing gas production catalyst according to claim 2, wherein the reforming catalyst layer and the shift catalyst layer are supported on the honeycomb carrier separately from upstream and downstream of hydrocarbon gas.   The hydrogen-containing gas production catalyst according to claim 2, wherein a reforming catalyst layer and a shift catalyst layer are supported on the honeycomb carrier in parallel with a gas flow from upstream to downstream of the hydrocarbon gas.   The reforming catalyst and the shift catalyst each have a catalyst component supported on a honeycomb carrier, and the honeycomb supported reforming catalyst and the honeycomb supported shift catalyst are disposed in the same casing. Item 2. The hydrogen-containing gas production catalyst according to Item 1.   2. The hydrogen-containing gas production catalyst according to claim 1, wherein the reforming catalyst and the shift catalyst are each formed into a granular shape, and the granular reforming catalyst and the granular shift catalyst are filled in the same casing. .   The hydrogen-containing gas production catalyst according to claim 1, wherein the reforming catalyst and the shift catalyst carry the reforming catalyst component and the shift catalyst component on the same carrier.   The hydrogen-containing gas production catalyst according to claim 9, wherein the reforming catalyst and the shift catalyst are supported by laminating the reforming catalyst component and the shift catalyst component on the same carrier, respectively.   The hydrogen-containing gas production catalyst according to claim 1, wherein the reforming catalyst contains rhodium.   The hydrogen-containing gas production catalyst according to any one of claims 1 to 10, wherein the shift catalyst contains platinum.   A hydrogen production method, comprising supplying a hydrocarbon to the hydrogen-containing gas production catalyst according to any one of claims 1 to 12, and controlling the temperature in the catalyst layer at 350 to 550 ° C to cause a reaction.   A method for producing hydrogen, comprising reacting the hydrogen-containing gas production catalyst according to any one of claims 1 to 12 with a water / hydrocarbon carbon ratio of 1 to 3.   A method for producing hydrogen, comprising reacting the hydrogen-containing gas production catalyst according to any one of claims 1 to 12 with an oxygen / hydrocarbon carbon ratio of 0.1 to 1.5.

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