JP2009241036A - Carbon monoxide conversion catalyst comprising composition for carbon monoxide conversion catalyst, and method of removing carbon monoxide using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbon monoxide conversion catalyst having excellent catalytic activity and durability, small in the deterioration of activity even when applied to a fuel cell and used as a water gas shift reaction catalyst which can be used for a long period of time, and a method of removing carbon monoxide using the carbon monoxide conversion catalyst. <P>SOLUTION: The carbon monoxide conversion catalyst contains (A) a copper oxide component, (B) a zinc oxide component and (C) an aluminum oxide component, wherein at least 0.01-0.5 mmol element of one of a group I, a group II, a group VIII, a group X and a group XIII per 1 g in total of (A)-(C) is contained as a (D) component. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a catalyst for removing carbon monoxide from a gas obtained by reforming hydrocarbons. More specifically, it is obtained by adding a trace amount of a specific element to a catalyst precursor material containing copper, zinc and aluminum and having an X-ray diffraction pattern showing a broad peak at a specific lattice spacing d (Å), The present invention also relates to a carbon monoxide conversion catalyst suitable as an aquatic gas shift reaction catalyst, and further to a carbon monoxide removal method using the carbon monoxide conversion catalyst.

  In recent years, new energy technology has attracted attention due to environmental problems, and fuel cells are attracting attention as one of the new energy technologies. This fuel cell converts chemical energy into electrical energy by electrochemically reacting hydrogen and oxygen, has high energy utilization efficiency, and is researched for practical use for consumer, industrial or automotive applications. Is widely and actively conducted.

  There are known types of fuel cells such as a phosphoric acid type, a molten carbonate type, a solid oxide type, and a solid polymer type depending on the type of electrolyte used. The hydrogen source for producing hydrogen for these fuel cells includes liquefied natural gas mainly composed of methane, city gas mainly composed of this natural gas, synthetic liquid fuel using natural gas as a raw material, and petroleum-based liquefied petroleum gas. Petroleum hydrocarbons such as naphtha and kerosene are the subject of research. When hydrogen is produced from these gaseous or liquid hydrocarbons, in general, after desulfurization treatment, the hydrocarbon is modified in the presence of a reforming catalyst such as partial oxidation reforming, autothermal reforming or steam reforming. Quality processing is performed.

  Although hydrogen and carbon monoxide are mainly obtained by the above reforming treatment, carbon monoxide can be converted into hydrogen and carbon dioxide by water and water gas shift reaction. The water gas shift reaction is also used to change the ratio of hydrogen and carbon monoxide in the water gas depending on the purpose of the synthesis reaction, but can also be applied for hydrogen production. The copper-zinc-aluminum catalyst used in the water gas shift reaction can operate at a relatively low temperature compared to the noble metal catalyst, so that the carbon monoxide concentration can be lowered to a low concentration of 1% or less. In the presence of copper, there is a problem that copper sintering occurs and deactivates. Therefore, it can be used for a long time in industrial equipment that operates under certain conditions, but when the catalyst is frequently started and stopped like a fuel cell and the atmosphere of oxidation and reduction is repeated, copper sintering is likely to occur. The catalyst tends to be deactivated. Catalysts with precious metals such as platinum supported on titania or ceria are highly durable, but their activity at low temperatures is not as good as that of copper-zinc-aluminum catalysts.

Therefore, the activity of the copper-zinc-aluminum catalyst and the durability of the catalyst (especially, the time during which the catalyst can maintain a practically satisfactory activity in a state where it is repeatedly started and stopped, sometimes referred to simply as durability) Various studies have been made to improve the above, and the following reports have been made.
Patent Document 1 states that the catalytic activity produced from a hydrotalcite-form aluminum and a catalyst precursor containing aluminum different from hydrotalcite is high. Group IA elements in oxide form, such as potassium oxide and cesium oxide, may be added to the catalyst, and typical amounts are described as about 50 ppm to 1000 ppm. In Patent Document 2, it is said that a shift catalyst having high activity can be obtained by supporting a hydrotalcite support with an oxide active species in which copper and a noble metal are combined. Patent Document 3 states that a catalyst obtained from a complex base carbonate composed of auricalcite-type copper and zinc is highly active in a methanol synthesis reaction.
Furthermore, in Patent Document 4, a catalyst containing 1 to 5% by weight of cesium or strontium of an existing copper-zinc catalyst is excellent in activity and durability. In Patent Document 5, it is assumed that a catalyst in which copper and an alkali metal element or alkaline earth metal element as a promoter element are supported on a support containing a zinc / aluminum composite oxide has high durability. It is disclosed that the cocatalyst element is preferably 1% by weight or more and 2% by weight or less.
However, none of them are yet sufficient as aquatic gas shift reaction catalysts for hydrogen production used in fuel cells that are frequently started and stopped.

JP 2005-52089A JP 2003-80072 A JP-A-9-187654 JP 11-244700 A JP 2004-321924 A

  The present invention has been made in view of such a situation, and is excellent in catalytic activity and durability, has little decrease in activity even when applied to a fuel cell, and is used as a catalyst for a water gas shift reaction that can be used for a long period of time. It is an object of the present invention to provide a carbon monoxide conversion catalyst comprising a carbon oxide conversion catalyst composition, and further a carbon monoxide removal method using the carbon monoxide conversion catalyst.

As a result of intensive studies to achieve the above object, the present inventors have added a trace amount of a specific element to a catalyst precursor material containing copper, zinc and aluminum and exhibiting a novel X-ray diffraction pattern. The catalyst obtained by calcining the carbon monoxide conversion catalyst composition is high in activity and durability, has little decrease in activity even when applied to a fuel cell, and becomes a catalyst for water gas shift reaction that can be used for a long time. And the present invention was completed based on this finding.
That is, the present invention
[1] (A) A copper oxide component, (B) a zinc oxide component, and (C) an aluminum oxide component, and 0.01 to 0 as component (D) with respect to 1 g of the total mass of (A) to (C) A catalyst for conversion of carbon monoxide containing at least one of the elements of Group 1, Group 2, Group 8, Group 10, and Group 13 of the 5 mmol periodic table;
[2] (A) The copper oxide component is 10 to 90% by mass, (B) the zinc oxide component is 5 to 50% by mass, and (C) the aluminum oxide component is 5 to 50% by mass ((A) to ( The sum of C) is 100% by mass), the specific surface area is 100 to 300 m 2 / g, and the copper oxide crystallite diameter is 200 mm or less;
[3] The carbon monoxide conversion catalyst according to the above [1] or [2], wherein the component (D) is any one of K, Cs, Na, Mg, Ba, Fe, Pt, and Ga,
[4] The catalyst for carbon monoxide conversion according to any one of the above [1] to [3], wherein the component content (D) is 0.02 to 0.1 mmol / g,
[5] Including copper, zinc and aluminum, lattice spacing d (Å) 5.0 ± 0.5 ±, 3.7 ± 0.3Å, 2.6 ± 0.2Å, 2.3 ± 0.2Å and A catalyst precursor characterized by having an X-ray diffraction pattern showing a broad peak at 1.7 ± 0.1%, and any one of the elements of Group 1, Group 2, Group 8, Group 10, and Group 13 of the periodic table A catalyst for carbon monoxide conversion according to any one of the above [1] to [3], which is obtained by calcining a simple substance or a compound containing the catalyst precursor in the catalyst precursor,
[6] A solution in which the precursor contains a copper salt, a zinc salt and an aluminum salt and a solution containing an alkali metal or alkaline earth metal hydroxide are mixed, and the pH of the mixture is 8.5 to 8.5. [5] the catalyst for carbon monoxide conversion, obtained by precipitation under the condition of 11.0,
[7] The carbon monoxide conversion catalyst according to [6], wherein the alkali metal or alkaline earth metal hydroxide is sodium hydroxide,
[8] The carbon monoxide conversion catalyst according to any one of the above [5] to [7], wherein the calcination temperature is 200 to 600 ° C.
[9] A solution containing a copper salt, a zinc salt and an aluminum salt is mixed with a solution containing an alkali metal or alkaline earth metal hydroxide, and the pH of the mixture is 8.5 to 11.0. After the catalyst precursor obtained by precipitation below contains a simple substance or a compound containing any of the elements of Group 1, Group 2, Group 8, Group 10, and Group 13 of the periodic table, they are added to 200 to 600. A method for producing a carbon monoxide conversion catalyst according to any one of the above [1] to [8], which is obtained by firing at ° C
[10] A method for removing CO from a hydrogen-containing gas, comprising a step of bringing the catalyst according to any one of [1] to [8] above into contact with a hydrogen-containing gas containing CO at 100 to 400 ° C., and [11] a hydrocarbon A fuel cell system comprising a step of removing CO from the hydrogen-containing gas produced by reforming of the hydrogen-containing gas from the hydrogen-containing gas of [10] above,
Is to provide.

  According to the present invention, the catalyst precursor material containing copper, zinc and aluminum and precipitated with sodium hydroxide as a precipitating agent at a specific pH and exhibiting a novel X-ray diffraction pattern is further added to groups 1 and 2 of the periodic table. , A catalyst obtained by calcining a composition for carbon monoxide conversion catalyst to which at least one specific element of at least one of Group 8, Group 10 and Group 13 elements is added, has high activity and durability, and is applied to fuel cells Even in such a case, it is possible to provide a catalyst for carbon monoxide conversion which is a catalyst for water gas shift reaction that can be used for a long period of time with little decrease in activity.

As a catalyst composition of the catalyst for carbon monoxide conversion of the present invention, when each element is represented by an oxide, (A) the copper oxide component is 10 to 90% by mass, preferably 30 to 80% by mass, (B) The zinc oxide component is 5 to 50% by mass, preferably 10 to 40% by mass, (C) the aluminum oxide component is 5 to 50% by mass, preferably 15 to 40% by mass, and (D) as the component (A) to The total mass of (C) is 0.01 to 0.5 mmol, preferably 0.02 to 0.1 mmol, and contains at least one element of Group 1, Group 2, Group 8, Group 10, and Group 13 of the Periodic Table. .
One of the features is that the amount of zinc oxide component is small and the amount of aluminum oxide component is large compared to a catalyst that has been considered to be optimal.
As the catalyst composition, if the copper oxide component departs from 10 to 90% by mass, the active species of copper is reduced and the catalytic activity is lowered, or the relative durability of the catalyst is lowered because zinc and aluminum are relatively reduced. There is a fear.
If the zinc oxide component deviates from 5 to 50% by mass as the catalyst composition, the durability of the catalyst may be reduced due to the decrease in zinc, or the catalytic activity may be decreased due to relatively little copper.
If the aluminum oxide is out of 5 to 50% by mass as the catalyst composition, the catalyst strength may decrease or the durability of the catalyst may decrease. Moreover, there is a possibility that the catalytic activity is lowered due to relatively little copper.
By adding a very small amount of the component (D) within the above range as the catalyst composition, the excellent effects of the present invention can be achieved. The element to be added as the component (D) is not particularly limited as long as it is an element of Group 1, Group 2, Group 8, Group 10, or Group 13 of the periodic table, but elements of Group 1 of the periodic table include K, Cs, Na and Group 2 elements are preferably Mg, Ba, Group 8 elements are Fe, Group 10 elements are Pt, and Group 13 elements are preferably Ga. Particularly preferred elements are K and Cs.
More preferably, the zinc oxide component does not contain zincite as the catalyst composition. By not containing zincite, the durability and activity of the carbon monoxide conversion catalyst of the present invention are further improved, and when mounted on a fuel cell reformer as a carbon monoxide conversion (shift) catalyst, There is an advantage that it can be used for a long time with little decrease in activity even if it is used repeatedly starting and stopping.

The physical properties of the copper-zinc-aluminum-based carbon monoxide conversion catalyst according to the present invention have a specific surface area of 120 to 300 m ² / g, preferably 120 to ²⁰⁰ m ² / g, and a carbon monoxide adsorption amount of 20 to 80 μmol / g. , Preferably 30 to 70 μmol / g, and the copper oxide crystallite diameter is 200 mm or less, preferably 150 mm or less.
The zinc oxide component is preferably present as at least zinc aluminum spinel (ZnAl ₂ O ₄ ). Finer crystals of zinc aluminum spinel are more effective in suppressing copper sintering, and the crystallite diameter is preferably 100 mm or less, particularly preferably 50 mm or less.
Presence of zincite and zinc aluminum spinel can be confirmed from a diffraction pattern by powder X-ray diffraction measurement.
The X-ray diffraction pattern of zincite is d = 2.475, d = 2.814, d = 2.602, d = 1.625, d = 1.477, d = 1.378.
Shows diffraction lines.
X-ray diffraction pattern of zinc aluminum spinel (ZnAl ₂ O ₄ ) is d = 2.442, d = 2.863, d = 1.432, d = 1.559, d = 1.653, d = 1.281
Shows diffraction lines.
If zinc aluminum spinel is in the vicinity of copper atoms, copper oxide or reduced copper in the presence of heat and water vapor or in a state where the catalyst is oxidized and reduced repeatedly will sinter and lose activity. It has an inhibitory effect, exists stably even in the presence of heat and water vapor, and under conditions of repeated oxidation and reduction atmospheres, suppresses copper sintering, and exhibits stable catalytic activity. On the other hand, it has been found that when the zinc oxide component is zincite, the zincite particles themselves are sintered by the repeated oxidation and reduction, thereby promoting copper sintering.
When the specific surface area deviates from 120 to 300 m ² / g, the catalytic activity decreases and the copper sintering suppression effect decreases.
The amount of carbon monoxide adsorbed is related to the amount of active sites of copper effective for the reaction, but the range of 20 to 80 μmol / g is preferable from the viewpoint of activity and durability. If it is too high, the durability is lowered.
When the copper oxide crystallite diameter exceeds 200 mm, the number of active points of copper effective for the reaction decreases, and therefore the activity decreases.
When the crystallite diameter of the zinc aluminum spinel exceeds 100%, the copper sintering suppression effect is lowered, which is not preferable from the viewpoint of durability.

The copper-zinc-aluminum-based carbon monoxide conversion catalyst according to the present invention has a copper / zinc atomic ratio of 1.0 or more and a zinc to aluminum atomic ratio (Zn / Al) of 0.1 to 1.5. It is preferable that Particularly preferably, the atomic ratio of copper / zinc is 2 to 10, and the atomic ratio of zinc to aluminum (Zn / Al) is 0.2 to 1.0.
If the atomic ratio of copper / zinc is less than 1.0, the activity is not sufficient.
If the atomic ratio of zinc to aluminum (Zn / Al) deviates from 0.1 to 1.5, the durability of the catalyst (especially starting and stopping) due to the fact that zinc aluminum spinel does not form after firing or does not generate a sufficient amount In the state where the catalyst is repeatedly used, the time during which the catalyst can maintain a practically satisfactory activity) is reduced, and zinc atoms are generated too much, and as a result, the durability of the catalyst is thought. May not improve as much.

The catalyst for carbon monoxide conversion of the present invention contains 0.01 to 1.0 mmol, preferably 0.02 to 1 g of the catalyst precursor material containing a simple substance or a compound containing the component (D) in the catalyst precursor material described later. It is preferable to sinter and prepare 0.8 mmol, particularly preferably 0.03 to 0.7 mmol added. This is because the component derived from the component (D) in the catalyst obtained by calcination is usually somewhat less than the simple substance or compound containing the component (D) before calcination.
The catalyst precursor material includes copper, zinc and aluminum, and the lattice spacing d (Å) is 5.0 ± 0.5Å, 3.7 ± 0.3Å, 2.6 ± 0.2Å, 2.3 ± 0. Substances containing copper, zinc and aluminum showing X-ray diffraction patterns similar to those of spertiniite minerals (Cu (OH) ₂ ) showing broad X-ray diffraction peaks at .2X and 1.7 ± 0.1Å. It is.
Further, the catalyst precursor material includes copper, zinc, and aluminum. In addition to the above X-ray diffraction pattern, the lattice spacing d (Å) is 8.4 ± 0.6Å and 4.2 ± 0.3Å. It may be a substance showing a broad X-ray diffraction peak, and 8.4 ± 0.6Å, 4.2 ± 0.3Å is hydroscarbroite mineral (Al ₁₄ (CO ₃ ) ₃ (OH) ₃₆ · n ( It is a substance showing an X-ray diffraction pattern similar to that of H ₂ O)).
In addition to the above two types of X-ray diffraction patterns, the catalyst precursor material exhibits an X-ray diffraction pattern (lattice spacing 2.3 ± 0.2 mm and 2.57 ± 0.2 mm) of Tenorite (CuO). Substances may be included, but there is no problem with catalyst performance if the amount is small.

Here, the measurement conditions of the X-ray diffraction pattern are as follows.
Cu-Kα ray: wavelength λ = 1.5406Å, output: 40 kV, 40 mA
Optical system: reflection method; 2θ · θ continuous scan, DS, SS slit: 1 °
RS slit: 0.3 mm, step interval: 0.02 °, scan speed: 1 ° / min

The method for producing the catalyst precursor material comprises mixing a solution containing a copper salt, a zinc salt and an aluminum salt and a solution containing sodium hydroxide (precipitating agent), and washing and drying the formed precipitate. Can be obtained by: When mixing a solution containing copper salt, zinc salt and aluminum salt with sodium hydroxide solution to coprecipitate copper, zinc and aluminum, mix one solution while stirring the other solution. May be. At this time, it is preferable to adjust so that the pH of a liquid mixture may be 8-11.5.
As the precipitant, an alkali metal or alkaline earth metal hydroxide is used. Sodium hydroxide, potassium hydroxide and barium hydroxide are preferred, and sodium hydroxide is most preferred. When an alkali or alkaline earth metal carbonate such as sodium carbonate is used, the catalyst precursor material of the present invention cannot be obtained.

As salt types of the copper salt and zinc salt, nitrates, chlorides, sulfates, hydrochlorides, organic acid salts such as acetates and citrates can be used, among which nitrates are preferable. As the aluminum salt, nitrate, chloride, hydrochloride, sulfate, hydroxide, sodium aluminate, pseudoboehmite and the like can be used, and among these, nitrate and sodium aluminate are preferable.
Mixing a solution containing copper, zinc and aluminum salts with a solution containing an alkali metal or alkaline earth metal hydroxide such as sodium hydroxide is maintained at a temperature of about 0 to about 90 ° C. with stirring. And do it. After formation of the precipitate, washing and filtration may be performed immediately, or after aging, washing and filtration may be performed.
Although there is no restriction | limiting in particular as drying conditions of the obtained deposit, What is necessary is just to carry out until drying is completed at the temperature of about room temperature-200 degreeC.
The catalyst for carbon monoxide conversion of the present invention comprises the above catalyst precursor by a method such as impregnation and evaporation to dryness using an aqueous solution of nitrate, hydroxide, acetate and citrate containing the component (D). The carbon monoxide conversion catalyst composition contained in the substance can be obtained by drying and firing at a temperature of about 200 to 600 ° C. The catalyst obtained by calcination does not show the X-ray diffraction pattern of the original catalyst precursor, but shows the X-ray diffraction pattern of copper oxide.
It may be accompanied by a small amount of zinc oxide X-ray diffraction pattern. The catalyst thus obtained is used as it is or after being granulated or tableted by an appropriate method. The particle size and shape of the catalyst can be arbitrarily selected depending on the reaction method and the shape of the reactor, and the catalyst of the present invention can be used in any reaction method such as a fixed bed and a fluidized bed.

The catalyst for carbon monoxide conversion of the present invention is particularly useful as a catalyst for water gas shift reaction.
The method for removing carbon monoxide using the carbon monoxide conversion catalyst of the present invention and utilizing the water gas shift reaction may vary depending on the concentration of carbon monoxide and hydrogen in the raw material gas and the content of the catalyst component. The reaction temperature is about 150 to 400 ° C., the reaction pressure is about normal pressure to 10 MPa (absolute pressure), the molar ratio of water vapor to carbon monoxide in the raw material gas is about 1 to 100, and the raw material gas (excluding water vapor) The space velocity (GHSV value) is suitably in the range of about 100 to 100,000 hr ⁻¹ .
In addition, the carbon monoxide removal method using the catalyst for carbon monoxide conversion of the present invention can be employed in a fuel cell system using a hydrogen-containing gas generated by hydrocarbon reforming.

EXAMPLES Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
The specific surface area of the catalyst, the copper surface area, the carbon monoxide adsorption amount, and the CuO crystallite diameter were measured by the following methods.
Measurement of physical properties of catalyst
(a) Specific surface area measurement The specific surface area measurement was performed using a specific surface area measurement device manufactured by Yuasa Ionics Co., Ltd., and about 100 mg of a sample was filled in a sample tube, and was subjected to heat dehydration in a nitrogen stream at 200 ° C. for 20 minutes as a pretreatment. Next, nitrogen (30%) / helium (70%) mixed gas was circulated at the liquid nitrogen temperature to adsorb nitrogen, and then desorbed and the specific surface area was determined from the amount of nitrogen adsorbed measured by a TCD detector.
(b) Copper surface area of the catalyst The copper surface area of the catalyst was measured by reducing with hydrogen gas for 120 minutes using a differential thermal balance apparatus manufactured by Bruker AXS. After purging with He at 90 ° C. for 60 minutes, nitrous oxide (1%) / helium (99%) gas was circulated at 90 ° C. to oxidize copper on the surface as shown in the following reaction formula. It was.
N ₂ O + 2Cu → N ₂ + Cu ₂ O
The weight change from Cu to Cu ₂ O is measured to calculate the number of copper atoms on the surface, and the copper area is calculated because the number of copper atoms present in 1 m ² is 1.46 × 10 ^19. did.
(c) CO adsorption amount measurement The CO adsorption amount measurement was performed by a pulse method using a pulse adsorption amount measuring device R6015 (manufactured by Okura Riken). About 200 mg of the sample was weighed and subjected to reduction treatment at 200 ° C. for 60 minutes under 100% -hydrogen as a pretreatment. Thereafter, purging was performed at 200 ° C. for 60 minutes with He. In the measurement, CO gas was introduced in pulses at 50 ° C. The CO pulse was repeated until no CO adsorption was observed, and the CO adsorption amount was measured.
(d) XRD measurement XRD measurement was performed using an X-ray diffractometer manufactured by Rigaku Corporation. The sample was filled in a glass sample cell and measured by an X-ray source Cu-Kα (1.5406 mm, monochromatized with a graphite monochromator), 2θ-θ reflection method. The crystallite diameters of CuO and ZnAl ₂ O ₄ were calculated from the Scherrer equation. (The crystallite size of ZnAl ₂ O ₄ was measured for Examples 1, 6, 8 and Comparative Example 1.)
(e) Composition analysis The amount of Cu, Zn, and Al in the catalyst was quantified by a plasma emission (ICP) method. CuO, ZnO, and Al ₂ O ₃ amounts were calculated from the quantitative measurement values of Cu, Zn, and Al, and the total was converted to 100% by mass.

Catalyst Activity Evaluation Method A reaction tube having an inner diameter of 12 mm was filled with 0.5 cc of each catalyst adjusted to 0.5 to 1 mm and 4 mL of SiC added thereto. In the reaction tube, the catalyst was reduced in an air stream of H ₂ / N ₂ = 20/80 at 230 ° C. for 2 hours, and then H ₂ / CO / CO ₂ / H under the condition of GHSV: 60,000 h ^−1. A gas of ₂ O = 49.9 / 9.9 / 10.2 / 30.0 (vol%) was introduced, and carbon monoxide shift reaction was carried out at 200 ° C. The obtained gas was sampled and its concentration was measured by gas chromatography. Based on this result, the CO conversion was determined by the following formula. The results are shown in Table 1.
CO conversion rate (%) = ((A−B) / A) × 100
In the above equation, A = CO amount on the reactor inlet side = (CO concentration before transformation (vol%)) × (gas amount before transformation (mL / min)) and B = CO amount on the reactor outlet side = ( CO concentration after modification (vol%)) × (gas amount after modification (mL / min)).

Production Example 1 Production of Catalyst Precursor Material 1415 g of copper nitrate trihydrate, 560 g of zinc nitrate hexahydrate, and 1650 g of aluminum nitrate nonahydrate were dissolved in 15 l of water to prepare solution A. A sodium hydroxide 2 mol / liter solution was prepared. Liquid A and sodium hydroxide solution were simultaneously added dropwise to a container containing 2 liters of water at 50 ° C. During the dropping, the precipitate was maintained at 50 ° C. with stirring, and the dropping rate of the sodium hydroxide solution was adjusted so that the pH was 9.5 to 10.0. The precipitate was aged for 3 hours, filtered, and thoroughly washed with water. The taken out precipitate was dried at 120 ° C. and then subjected to X-ray diffraction measurement. Broad peaks were shown at lattice spacings d (ピ ー ク) of 5.07Å, 3.70Å, 2.61Å, 2.27Å and 1.71Å. An X-ray diffraction diagram is shown in FIG.

Examples 1-15 and Comparative Examples 1-3
A portion (20 g) of the catalyst precursor material obtained in Production Example 1 was impregnated with an aqueous solution of the compounds shown in Table 1. After drying at 120 ° C., it was calcined at 350 ° C. for 3 hours to obtain a catalyst. Each catalyst was compression-molded and pulverized, and sized to 0.5 mm to 1 mm.
The composition of this catalyst was 54.7% by mass of copper oxide, 19.4% by mass of zinc oxide, and 25.9% by mass of aluminum oxide.
Next, the CO conversion rate (%) of each catalyst was measured based on the activity evaluation method of the catalyst. The evaluation results are shown in Table 1.

2 is an X-ray diffraction pattern of a catalyst precursor obtained in Production Example 1. FIG.

  According to the present invention, the catalyst precursor material containing copper, zinc and aluminum and exhibiting a novel X-ray diffraction pattern is further added to at least one element of Group 1, Group 2, Group 8, Group 10 and Group 13 of the periodic table. Carbon monoxide is a catalyst for water gas shift reaction that can be used for a long period of time because the catalyst obtained by adding a very small amount of a specific element and calcining has high activity and durability, has little decrease in activity even when applied to a fuel cell A conversion catalyst can be provided.

Claims (11)

(A) A copper oxide component, (B) a zinc oxide component and (C) an aluminum oxide component, and 0.01 to 0.5 mmol of (D) component with respect to 1 g of the total mass of (A) to (C) A catalyst for carbon monoxide conversion comprising at least one of Group 1, Group 2, Group 8, Group 10, and Group 13 elements of the Periodic Table. (A) The copper oxide component is 10 to 90% by mass, (B) the zinc oxide component is 5 to 50% by mass, and (C) the aluminum oxide component is 5 to 50% by mass ((A) to (C) ^{2. The} catalyst for carbon monoxide conversion according to claim 1, wherein the sum is 100% by mass), the specific surface area is 100 to 300 m ² / g, and the copper oxide crystallite diameter is 200 mm or less. The catalyst for carbon monoxide conversion according to claim 1 or 2, wherein the component (D) is any one of K, Cs, Na, Mg, Ba, Fe, Pt, and Ga. (D) Component content is 0.02-0.1 mmol / g, The carbon monoxide conversion catalyst in any one of Claims 1-3.   Including copper, zinc and aluminum, lattice spacing d (Å) 5.0 ± 0.5Å, 3.7 ± 0.3Å, 2.6 ± 0.2Å, 2.3 ± 0.2Å and 1.7 A catalyst precursor characterized by having an X-ray diffraction pattern showing a broad peak at ± 0.1Å, and a simple substance containing any of the elements of Group 1, Group 2, Group 8, Group 10, and Group 13 of the periodic table Or the catalyst for carbon monoxide conversion in any one of Claims 1-4 obtained by baking the thing containing the compound.     The precursor contains a solution containing a copper salt, a zinc salt and an aluminum salt and a solution containing an alkali metal or alkaline earth metal hydroxide, and the pH of the mixture is 8.5 to 11.0. The catalyst for carbon monoxide conversion according to claim 5, which is obtained by precipitation under the conditions of   7. The carbon monoxide conversion catalyst according to claim 6, wherein the alkali metal or alkaline earth metal hydroxide is sodium hydroxide.   The catalyst for carbon monoxide conversion according to any one of claims 5 to 7, wherein the calcination temperature is 200 to 600 ° C.   A solution containing a copper salt, a zinc salt and an aluminum salt is mixed with a solution containing an alkali metal or alkaline earth metal hydroxide, and the pH of the mixture solution is precipitated under a condition of 8.5 to 11.0. The catalyst precursor obtained by adding a simple substance or a compound containing any of the elements of Group 1, Group 2, Group 8, Group 10, and Group 13 of the periodic table to the catalyst precursor, The manufacturing method of the catalyst for carbon monoxide conversion in any one of Claims 1-8 obtained by baking at 200-600 degreeC.   A method for removing CO from a hydrogen-containing gas, comprising a step of bringing the catalyst according to any one of claims 1 to 8 into contact with a hydrogen-containing gas containing CO at 100 to 400 ° C.   A fuel cell system comprising a step of removing CO from a hydrogen-containing gas produced by reforming a hydrocarbon using the method for removing CO from a hydrogen-containing gas according to claim 10.

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