Hydrogen gas production method

Abstract

To provide a method for manufacturing hydrogen gas by which it is easy to increase an amount of generation of hydrogen gas.SOLUTION: A method for manufacturing hydrogen gas includes bringing gas to be processed containing ammonia into contact with a treatment material containing a catalyst, thereby decomposing the ammonia into hydrogen gas and nitrogen gas by the catalyst. The catalyst includes a carrier and an active metal carried on the carrier. The carrier includes spinel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for producing hydrogen gas. By law More specifically, the present invention relates to a method for producing hydrogen gas using a catalyst. By law Regarding. [Background technology]

[0002] Patent Document 1 describes a method for producing hydrogen. This method includes a step of heating a catalyst layer to 200°C or higher and 700°C or lower, and a step of passing an ammonia-containing gas through the heated catalyst layer to decompose the ammonia into nitrogen gas and hydrogen gas, and is characterized in that the catalyst layer uses a treatment material comprising a composite containing at least one of γ-alumina and θ-alumina and a sintered clay compound, and a metal supported by the composite. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-20433 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned hydrogen production methods, it is desirable to increase the amount of hydrogen produced.

[0005] The present disclosure aims to provide a method for producing hydrogen gas that facilitates an increase in the amount of hydrogen gas produced. do. [Means for solving the problem]

[0006] In a method for producing hydrogen gas according to one aspect of the present disclosure, a gas to be treated containing ammonia is brought into contact with a treatment material containing a catalyst, and the ammonia is decomposed into hydrogen gas and nitrogen gas by the catalyst. The catalyst includes a support and an active metal supported on the support. The support includes spinel.

[0007] A method for producing a catalyst according to one aspect of the present disclosure includes a support preparation step of preparing a support containing a spinel, and a supporting step of supporting an active metal on the support obtained in the support preparation step. The support preparation step includes a filling step, a drying step, and a calcining step. The filling step involves immersing a support raw material containing alumina in a treatment solution containing magnesium ions, thereby filling the treatment solution into pores of the support raw material. The drying step involves drying the support raw material, whose pores have been filled with the treatment solution, after the filling step, to precipitate a magnesium salt on the support raw material. The calcining step involves calcining the support raw material, from which the magnesium salt has been precipitated, after the drying step, to produce the spinel. [Effects of the Invention]

[0008] The present disclosure has the advantage of increasing the amount of hydrogen gas produced. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing an apparatus used in the method for producing hydrogen gas according to this embodiment. [Figure 2] FIG. 2 shows a profile obtained by X-ray diffraction of the catalyst support obtained by the catalyst production method according to this embodiment. [Figure 3] FIG. 3 is a graph showing the relationship between the reaction temperature and the ammonia decomposition reaction rate in the examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] (Embodiment) 1. Overview To achieve carbon neutrality (decarbonization) of city gas, demonstration tests are being conducted on methanation, which synthesizes e-methane from hydrogen produced by water electrolysis using renewable electricity such as solar power, and carbon dioxide recovered from combustion exhaust gases, etc.

[0011] Recently, ammonia has been attracting attention as a hydrogen carrier, and ammonia methanation, which involves decomposing ammonia into hydrogen and nitrogen and then reacting the resulting hydrogen with carbon dioxide to synthesize e-methane, has been attracting attention.

[0012] In the method for producing hydrogen gas according to the present embodiment, a gas to be treated containing ammonia is brought into contact with a treating material containing a catalyst, whereby the ammonia is decomposed into hydrogen gas and nitrogen gas by the catalyst. The catalyst includes a carrier and an active metal supported on the carrier, and the carrier contains spinel.

[0013] In the hydrogen gas production method of this embodiment, a catalyst in which an active metal is supported on a support containing spinel is used, and therefore the catalyst, in which the active metal is highly dispersed within the pores of the support, can be brought into contact with ammonia. This increases the contact efficiency between the ammonia in the gas to be treated and the active metal in the catalyst, and increases the amount of hydrogen produced.

[0014] The catalyst manufacturing method according to this embodiment includes a carrier preparation step and a supporting step. The carrier preparation step is a step of preparing a carrier containing spinel. The supporting step is a step of supporting an active metal on the carrier obtained in the carrier preparation step. The carrier preparation step includes a filling step, a drying step, and a calcining step. The filling step involves immersing a carrier raw material containing alumina in a treatment solution containing magnesium ions, thereby filling the treatment solution into the pores of the carrier raw material. The drying step involves drying the carrier raw material whose pores have been filled with the treatment solution after the filling step, thereby precipitating magnesium salt on the carrier raw material. The calcining step involves calcining the carrier raw material with the magnesium salt precipitated after the drying step, thereby producing a spinel.

[0015] In the catalyst production method of this embodiment, since the active metal is supported on the support containing spinel, it is possible to obtain a catalyst in which the active metal is highly dispersed within the pores of the support.

[0016] 2.Details <Hydrogen gas production method> The hydrogen gas production device used in this embodiment is shown in Figure 1. This hydrogen gas production device produces hydrogen gas from ammonia gas by catalytic action.

[0017] The hydrogen production device 10 includes a reactor 11, a heating furnace 12, a thermocouple 13, an ammonia supply pipe 14, a diluent gas supply pipe 15, a hydrogen introduction pipe 16, a nitrogen introduction pipe 17, a thermocouple 20, and the like.

[0018] The reactor 11 is a container for bringing the gas 2 to be treated, which contains ammonia, into contact with the treatment material 1, which contains catalyst particles, and is made of, for example, a stainless steel pipe. The treatment material 1 is accommodated in the reactor 11.

[0019] The heating furnace 12 is used to heat the reactor 11 and adjust the temperature inside the reactor 11, and is composed of, for example, an electric furnace.

[0020] The thermocouple 20 is a temperature sensor for measuring the temperature of the treatment material 1. By measuring the temperature of the treatment material 1 with the thermocouple 20, the operation of the heating furnace 12 can be controlled based on the reading of the thermocouple 13. Therefore, the hydrogen gas production apparatus 10 can control the temperature when the ammonia gas comes into contact with the catalyst.

[0021] The ammonia supply pipe 14 is a pipe for supplying ammonia gas to the reactor 11. A mass flow controller 140 is provided in the ammonia supply pipe 14, and the mass flow controller 140 is configured to be able to adjust the amount of ammonia gas supplied to the reactor 11.

[0022] The diluent gas supply pipe 15 is a pipe for supplying the diluent gas to the reactor 11. The diluent gas supply pipe 15 is provided with a mass flow controller 150, and is configured so that the amount of the diluent gas supplied to the reactor 11 can be adjusted by the mass flow controller 150.

[0023] The hydrogen inlet pipe 16 is a pipe for introducing hydrogen gas into the reactor 11. The hydrogen inlet pipe 16 is provided with a mass flow controller 160, and is configured so that the amount of hydrogen gas introduced into the reactor 11 can be adjusted by the mass flow controller 160.

[0024] The nitrogen inlet pipe 17 is a pipe for introducing nitrogen gas into the reactor 11. The nitrogen inlet pipe 17 is provided with a mass flow controller 170, and is configured so that the amount of nitrogen gas introduced into the reactor 11 can be adjusted by the mass flow controller 170.

[0025] The diluent gas supply pipe 15, the hydrogen introduction pipe 16, and the nitrogen introduction pipe 17 are each connected to a common pipe 18, and the diluent gas, hydrogen gas, or nitrogen gas is supplied or introduced into the reactor 11 from the diluent gas supply pipe 15, the hydrogen introduction pipe 16, and the nitrogen introduction pipe 17, respectively, through the common pipe 18.

[0026] Hydrogen gas is produced using the hydrogen gas production apparatus 10 as described above as follows.

[0027] First, hydrogen gas and nitrogen gas are introduced into the reactor 11 from the hydrogen inlet pipe 16 and the nitrogen inlet pipe 17 through the common pipe 18. Then, the reactor 11 is heated by the heating furnace 12 and maintained at a predetermined temperature for a predetermined time, whereby the metal oxide of the active metal contained in the catalyst in the treatment material 1 is reduced to the metal.

[0028] Next, reactor 11 is stabilized at a predetermined temperature by heating furnace 12, and ammonia gas is supplied to reactor 11 through ammonia supply pipe 14. Also, diluent gas is supplied to reactor 11 through diluent gas supply pipe 15. The ammonia gas and diluent gas supplied to reactor 11 are mixed in reactor 11, and gas to be treated 2 is prepared.

[0029] Next, the gas 2 to be treated comes into contact with the treatment material 1 in the reactor 11. As a result, the ammonia gas in the gas to be treated comes into contact with the catalyst in the treatment material 1, and the ammonia gas is decomposed into hydrogen gas and nitrogen gas by catalytic action.

[0030] Thereafter, hydrogen gas is extracted from the reactor 11 through the exhaust pipe 19, thereby producing hydrogen gas.

[0031] In the above-described method for producing hydrogen gas, the ammonia gas supplied to the reactor 11 is preferably produced by evaporating liquid ammonia. This allows dry ammonia gas that does not contain impurities such as moisture to be supplied to the reactor 11, thereby improving the efficiency of hydrogen gas production. For example, wet ammonia gas obtained by bubbling aqueous ammonia contains a large amount of moisture and has an extremely low ammonia content, so even if the decomposition rate of ammonia by the catalyst is high, the efficiency of hydrogen gas production may decrease. Note that ammonia gas may unavoidably contain moisture.

[0032] The diluent gas supplied to the reactor 11 is used to dilute the ammonia gas. The diluent gas makes it difficult for the ammonia gas to condense in the gas to be treated 2, thereby increasing the efficiency of hydrogen gas production. It is preferable to use an inert gas such as argon gas or helium gas as the diluent gas.

[0033] There are no particular restrictions on the mixture ratio of ammonia gas and diluent gas in the gas to be treated 2. If the ammonia supply pipe 14 can maintain a sufficient temperature and there is no risk of ammonia condensation, diluent gas need not be used. Since too much diluent gas reduces the efficiency of ammonia production, the mixture ratio of ammonia gas and diluent gas in the gas to be treated 2 can be set to a volume ratio of 30:70 to 100:0. This makes it possible to suppress condensation of ammonia gas without reducing the efficiency of hydrogen gas production.

[0034] The temperature inside the reactor 11 is preferably 300°C or higher and 600°C or lower. If the temperature inside the reactor 11 is lower than 300°C, the ammonia decomposition reaction is unlikely to occur, which may result in lower hydrogen production efficiency. Furthermore, if the temperature inside the reactor 11 exceeds 600°C, the energy loss due to the operation of the heating furnace 12 increases. The temperature inside the reactor 11 is more preferably 350°C or higher and 600°C or lower.

[0035] The flow rate of the gas 2 to be treated passing through the treatment material 1 is 0.1 m per ton of the treatment material 1. 3 / second or more 5m 3 It is preferable that the flow rate of the gas 2 to be treated passing through the treatment material 1 is 0.1 m / s or less. 3 If the flow rate is less than 5 m / sec, the amount of the gas 2 to be treated passing through the treatment material 1 per unit time will be small, and the efficiency of hydrogen production will be reduced. 3 If the time exceeds 1 / sec, the contact between the catalyst and the ammonia gas becomes insufficient, the ammonia is not easily decomposed, and the efficiency of hydrogen production decreases. Note that the flow rate of the gas 2 to be treated passing through the treatment material 1 can be adjusted by adjusting the amount of ammonia gas supplied to the reactor 11 using the mass flow controller 140, by adjusting the amount of dilution gas supplied to the reactor 11 using the mass flow controller 150, or by adjusting the volume of the reactor 11.

[0036] The catalyst used in this embodiment comprises a carrier and an active metal, and the carrier contains spinel. The carrier supports the active metal. The active metal exhibits catalytic action (ammonia decomposition action). Nickel or ruthenium can be used as the active metal. Compared to nickel, ruthenium exhibits high catalytic action in small amounts and at low temperatures, but is expensive. For this reason, it is preferable to use nickel, which is easily available and inexpensive.

[0037] Spinel is an oxide mineral having a chemical composition of magnesium aluminate (MgAlO4). The spinel used as the support of this embodiment has a specific surface area of, for example, 50 m 2 / g or more, total pore volume is 0.2 cm 3 / g or more, and an average pore diameter of 5 nm to 50 nm. The average particle diameter of the spinel used as the support of this embodiment is not particularly limited. By using a spinel with such properties as the support, a sufficient amount of active metal can be supported, and the catalyst can more easily exert its ammonia decomposition function. The specific surface area, total pore volume, and average pore diameter can be measured by gas adsorption, and the average particle diameter can be determined by particle size distribution measurement using laser diffraction.

[0038] The average particle size of the treatment material 1 packed in the reactor 11 is preferably 1 mm or more and 10 mm or less. If the average particle size of the treatment material 1 is smaller than 1 mm, the differential pressure of the circulating gas increases, increasing the introduction pressure of the gas to be treated and increasing energy consumption. On the other hand, if the average particle size of the treatment material 1 is larger than 10 mm, the contact efficiency between the treatment material 1 and the gas to be treated 2 decreases, resulting in a decrease in hydrogen production efficiency. If the average particle size of the carrier constituting the treatment material 1 is less than 1 mm, it can be molded by a method such as compression molding, and crushed and classified as necessary to adjust the average particle size. Similarly, if the average particle size exceeds 10 mm, it can be adjusted by crushing and classifying. It is more preferable to use a treatment material 1 with an average particle size of 2 mm or more and 6 mm or less. The average particle size of the treatment material 1 can be determined by a sieving test method.

[0039] The catalyst used in this embodiment has a spinel support, and therefore is superior in the decomposition of ammonia gas compared to other supports such as alumina. While the mechanism is unclear, it is believed that the high dispersibility of the active metal within the pores of the spinel results in a large specific surface area for the active metal, enabling efficient contact with ammonia. This increases the contact efficiency between ammonia gas in the gas to be treated and the active metal in the catalyst, facilitating the decomposition reaction of ammonia gas and resulting in superior ammonia gas decomposition. Furthermore, spinel has high acidity and excellent adsorption properties for alkaline ammonia. Therefore, increasing the concentration of ammonia adsorbed on the support increases the probability of contact between the active metal surface and the adsorbed ammonia. This facilitates the decomposition reaction of ammonia gas and results in superior ammonia gas decomposition.

[0040] The amount of the active metal supported varies depending on the supported metal. Considering the ammonia decomposition performance of a catalyst in which the supported metal is nickel, the amount is 0.1 to 30% by mass, preferably 1 to 25% by mass, and more preferably 5 to 20% by mass. Considering the ammonia decomposition performance of a catalyst in which the supported metal is ruthenium, the amount is 0.01 to 10% by mass, preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass.

[0041] Although Patent Document 1 describes that γ-alumina has a spinel-type crystal structure (

[0018] ), this merely describes the crystal structure, and the chemical composition of the carrier is γ-alumina.

[0042] The hydrogen gas produced as described above is used, for example, as a raw material for hydrogen gas in ammonia methanation.

[0043] That is, in the above-mentioned method for producing hydrogen gas, the decomposition reaction of ammonia shown in the following chemical reaction formula (1) occurs.

[0044] 8NH3 → 12H2 + 4N2…(1) The hydrogen gas thus obtained can be used to produce methane via the following chemical reaction equation (2) of the Sabatier reaction:

[0045] 12H2+3CO2→3CH4+6H2O …(2) From equations (1) and (2), the following reaction equation (3) showing ammonia methanation is established.

[0046] 8NH3+3CO2→3CH4+4N2+6H2O…(3) <Catalyst manufacturing method> The catalyst manufacturing method according to this embodiment includes a carrier preparation step and a supporting step. The carrier preparation step is a step of preparing a carrier containing spinel. The supporting step is a step of supporting an active metal on the carrier obtained in the carrier preparation step.

[0047] The carrier preparation step includes a filling step, a drying step, and a calcination step.

[0048] The filling step is a step of filling the pores of the support raw material containing alumina with a treatment solution containing magnesium ions by immersing the support raw material in the treatment solution containing magnesium ions. The treatment solution is an aqueous solution containing magnesium ions, and can be prepared by dissolving a magnesium raw material such as magnesium nitrate, magnesium chloride, or magnesium phosphate in water. The magnesium ion concentration in the treatment solution is not particularly limited as long as it is sufficiently soluble in water. A higher concentration requires less water to be used, which saves energy in the subsequent drying step. The alumina contained in the support raw material can be γ-alumina, χ-alumina, θ-alumina, or the like.

[0049] In this embodiment, after the carrier raw material is immersed in the treatment solution, it is preferable to maintain this state in a vacuum for a certain period of time. This improves the degree to which the treatment solution fills the pores of the carrier raw material, and increases the amount of magnesium ions supplied to the carrier raw material. In this embodiment, the carrier raw material immersed in the treatment solution is placed in a vacuum desiccator, which gradually creates a vacuum and then maintains the vacuum for 0.5 to 2 hours.

[0050] Conventionally, a pore filling method has been used industrially in such a filling step. The pore filling method is a method in which the pore volume of a support such as alumina is measured, an amount of aqueous solution equal to the measured volume is added, and the mixture is mixed and stirred to fill the pores of the alumina with a treatment liquid such as an aqueous magnesium nitrate solution by utilizing capillary action. The pore filling method can also be used in this embodiment.

[0051] The drying step is a step of drying the carrier raw material whose pores have been filled with the treatment solution after the filling step, thereby precipitating a magnesium salt in the pores of the carrier raw material. The precipitated magnesium salt is a supply material of magnesium ions, such as magnesium nitrate, magnesium chloride, or magnesium phosphate.

[0052] The calcination step is a step in which the support raw material from which the magnesium salt has been precipitated is calcined after the drying step to produce spinel. This causes magnesium oxide (MgO) to react with alumina (Al2O3) in the support raw material, producing spinel (MgAl2O4). The calcination step involves pre-calcination at 500°C to 700°C for 1 to 3 hours, followed by calcination at 900°C to 1200°C for 4 to 6 hours.

[0053] After the spinel carrier is produced in this manner in the carrier preparation step, a supporting step is carried out in which an active metal is supported on the carrier.

[0054] The supporting step can be exemplified by a method of impregnating a support with an aqueous solution containing an active metal. In this method, first, the support is impregnated with an aqueous solution containing metal ions such as nickel or ruthenium. After the impregnation, the water is removed using an evaporator or the like, and then the support is calcined to support the metal oxide, which is the active component, on the support. For example, when supporting nickel, the support is impregnated with an aqueous solution containing nickel ions, the water is removed, and the support is calcined at about 300 to 500°C for 2 hours. [Example]

[0055] (Example) A spinel support was produced by the following support preparation process.

[0056] (1) Impregnation Using a standard balance (zero-adjusted), place 25.6 g (0.1 mol) of magnesium nitrate hexahydrate into a weighing dish with a medicine spoon, and confirm the weight using an electronic balance (zero-adjusted). Similarly, place 10.2 g (0.1 mol) of alumina (AKP-G15, manufactured by Sumitomo Chemical) into the weighing dish, and place magnesium nitrate in an evaporating dish. Add 100 ml of pure water to the evaporating dish and stir with a glass rod until the magnesium nitrate is completely dissolved. Add the alumina to the magnesium nitrate solution and completely submerge it in water. In this state, place a watch glass on the evaporating dish, place it in a vacuum desiccator, slowly create a vacuum, and leave it for 1 hour. Then, let air into the desiccator and remove the evaporating dish.

[0057] (2) Evaporation and drying After impregnation, place the evaporating dish on a hot plate. Set the temperature to 150°C and begin heating. Once the alumina on the evaporating dish begins to emerge above the water surface, stir occasionally with a glass rod. As the water content decreases, the alumina particles will aggregate, so stir as much as possible to prevent solidification. Once all the water in the evaporating dish has evaporated, continue heating while flattening the mixture with the glass rod. Crush the solidified material with the glass rod and heat until it becomes smooth.

[0058] (3) Drying After evaporation and drying, the alumina is dried in a dryer at 110°C for 12 hours or more.

[0059] (4) Pre-firing and firing After drying, the alumina is calcined in an electric furnace at 600°C for 2 hours and then fired at 1000°C for 5 hours.

[0060] The diffraction pattern of the support obtained as described above was measured by X-ray diffraction (XRD). The chart obtained by XRD is shown in Figure 2. The ● in Figure 2 indicates reference data for spinel. This identifies the support obtained as spinel.

[0061] A catalyst was prepared by supporting nickel as an active metal on a spinel support through the following supporting process.

[0062] An aqueous solution containing nickel nitrate is placed in an evaporating dish and impregnated into the spinel support. After impregnation, the water is removed on a hot plate and the support is dried at 110°C for at least 12 hours. After this, the support is calcined at 500°C for 2 hours to support the nickel.

[0063] In this way, a catalyst in which nickel was supported on spinel was prepared.

[0064] (Comparative Example) Alumina was used as a support, and nickel was supported on the support to produce a catalyst. The method for supporting nickel was the same as in the examples.

[0065] (Properties of the support and catalyst) The specific surface area, total pore volume, and average pore diameter of the carrier and catalyst were measured for the examples and comparative examples. The results are shown in Table 1.

[0066] [Table 1]

[0067] (Ammonia decomposition performance) The ammonia decomposition reaction rate was measured using the catalysts of the example and comparative example.

[0068] The hydrogen gas production apparatus 10 shown in Figure 1 was used. The reactor 11 had a volume of 114 cm 3 Into this reactor 11, 2.7 g of the catalyst of the Example or Comparative Example was placed as the treating material 1. Hydrogen and nitrogen were passed through this reactor at 40 cc / min and 160 cc / min, respectively, and reduction was carried out at 500°C for 2 hours. Next, ammonia gas was supplied to the reactor 11 through the ammonia supply pipe 14, and helium gas was supplied through the dilution gas supply pipe 15. The supply rates of ammonia gas and helium gas were each 50 cm 3 / min. Then, while adjusting the temperature (reaction temperature) inside the reactor 11 with the heating furnace 12, a mixed gas of ammonia gas and helium gas was passed as the gas to be treated 2 through the treatment material 1 to decompose the ammonia gas. The treated gas was then discharged through the discharge pipe 19 and analyzed by gas chromatography. From the results, the decomposition reaction rate of ammonia gas was calculated. The results are shown in Table 2 and the graph in Figure 3. The numbers at the top of Table 2 are the reaction temperatures (°C). In Figure 3, the solid line shows the results of the example, and the dotted line shows the results of the comparative example.

[0069] [Table 2]

[0070] As is clear from Fig. 3, the ammonia decomposition reaction rate was higher in the Examples than in the Comparative Examples. In particular, even when the reaction temperature was in the low temperature range (400°C to 460°C), the ammonia decomposition reaction rate was higher in the Examples.

[0071] (summary) As described above, in the method for producing hydrogen gas according to the first aspect, a gas to be treated containing ammonia is brought into contact with a treatment material containing a catalyst, and the ammonia is decomposed into hydrogen gas and nitrogen gas by the catalyst. The catalyst includes a carrier and an active metal supported on the carrier. The carrier includes spinel.

[0072] According to this embodiment, the contact efficiency between the ammonia in the gas to be treated and the active metal in the catalyst is increased, and the amount of hydrogen gas produced is likely to increase.

[0073] A second aspect is the method for producing hydrogen gas according to the first aspect, wherein the active metal is at least one selected from nickel and ruthenium.

[0074] According to this aspect, the gas to be treated can be treated with a catalyst that has excellent ammonia decomposition ability.

[0075] A third aspect is the method for producing hydrogen gas according to the first or second aspect, wherein the ammonia-containing gas to be treated is a dry gas that does not contain moisture.

[0076] According to this embodiment, it is possible to treat a gas to be treated that has a high concentration of ammonia, and it is possible to increase the efficiency of decomposing ammonia.

[0077] A catalyst manufacturing method according to a fourth aspect includes a carrier preparation step and a supporting step. The carrier preparation step is a step of preparing a carrier containing spinel. The supporting step is a step of supporting an active metal on the carrier obtained in the carrier preparation step. The carrier preparation step includes a filling step, a drying step, and a calcining step. The filling step involves immersing a carrier raw material containing alumina in a treatment solution containing magnesium ions, thereby filling the treatment solution into the pores of the carrier raw material. The drying step involves drying the carrier raw material whose pores have been filled with the treatment solution after the filling step, thereby precipitating magnesium salt on the carrier raw material. The calcining step involves calcining the carrier raw material with the magnesium salt precipitated after the drying step, to produce a spinel.

[0078] According to this embodiment, since the active metal is supported on the support containing spinel, a catalyst can be obtained in which the active metal is highly dispersed within the pores of the support. [Explanation of symbols]

[0079] 1. Treated material 2. Gas to be treated

Claims

1. A method for producing hydrogen gas, in which a gas to be treated containing ammonia is brought into contact with a treating material containing a catalyst, and the ammonia is decomposed into hydrogen gas and nitrogen gas by the catalyst, The catalyst comprises a support and nickel, which is an active metal, supported on the support; the support comprises a spinel; The spinel is a filling step of filling pores of a support raw material containing alumina with a treatment solution containing magnesium ions by immersing the support raw material in the treatment solution; a drying step of drying the carrier raw material with the treatment solution filled into the pores after the filling step to precipitate a magnesium salt on the carrier raw material; a calcination step of calcining the carrier raw material from which the magnesium salt has been precipitated after the drying step to produce the spinel in the carrier raw material; is obtained by The ammonia-containing gas to be treated is a dry gas that does not contain moisture, the filling step includes placing the carrier raw material immersed in the treatment solution in a vacuum desiccator, gradually creating a vacuum, and then maintaining the vacuum for 0.5 to 2 hours; A method for producing hydrogen gas.

2. The moisture-free dry gas is produced by evaporating liquid ammonia. The method for producing hydrogen gas according to claim 1 .

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