A rare earth zirconate supported transition metal catalyst, its preparation method and use
By using rare earth zirconate-supported transition metal catalysts, the problems of low catalyst activity, low stability, and high cost in existing ammonia decomposition hydrogen production technologies have been solved, achieving efficient and low-cost ammonia decomposition hydrogen production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2026-06-16
AI Technical Summary
Existing ammonia decomposition hydrogen production technologies suffer from low catalyst activity, low stability, and high cost, which limits their large-scale application.
A rare earth zirconate-supported transition metal catalyst was prepared by impregnation, drying, calcination and reduction steps. The catalyst used cerium zirconate, lanthanum zirconate and other supports as carriers, and iron, cobalt and nickel as active components. The preparation process is simple and the raw materials are inexpensive.
It exhibits high ammonia decomposition activity and stability under low pressure, low temperature and high space velocity, which reduces catalyst cost and broadens the ammonia decomposition catalytic material system.
Smart Images
Figure BDA0005184088590000071 
Figure BDA0005184088590000081
Abstract
Description
Technical Field
[0001] This application relates to a rare earth zirconate-supported transition metal catalyst, its preparation method and application, belonging to the field of catalytic materials. Background Technology
[0002] Hydrogen energy, as an important component of my country's energy system, has broad development prospects in the future. By 2060, my country's annual hydrogen demand will reach 130 million tons, accounting for 20% of final energy consumption. The hydrogen energy industry chain mainly includes three parts: hydrogen production, storage and transportation, and hydrogen energy utilization. However, the hydrogen energy industry chain currently faces two major challenges: first, high storage and transportation costs due to hydrogen's flammability, explosiveness, and low volumetric energy density at normal temperature and pressure; second, inherently low safety. To promote the development of the hydrogen energy industry, corresponding measures need to be taken to address these two key technological bottlenecks, such as developing safer and more efficient storage and transportation technologies to improve the safety and economics of the hydrogen energy industry chain.
[0003] Ammonia offers numerous advantages as a highly efficient hydrogen storage medium. Among these, ammonia decomposition for hydrogen production is an important technological route. In this process, ammonia is decomposed into nitrogen and hydrogen using a highly efficient catalyst, and the hydrogen is then purified to meet practical needs. Ammonia decomposition for hydrogen production emits no carbon dioxide, making it environmentally friendly and possessing significant development potential in the hydrogen energy industry. Furthermore, researching and optimizing catalysts for ammonia decomposition for hydrogen production can improve efficiency and reduce costs, contributing to the widespread application of this technology and achieving a green energy transition.
[0004] In the field of ammonia decomposition for hydrogen production, the most effective catalysts are currently Ru-based catalysts doped with K, Ba, and Cs and supported on various carbon supports and metal oxides. However, their high cost limits their large-scale application. Among these, non-precious metal catalysts such as iron-based, cobalt-based, and nickel-based catalysts are inexpensive, but their activity is slightly lower than that of ruthenium-based catalysts, and the active components are prone to sintering and deactivation at high temperatures. Therefore, developing novel, low-cost, and efficient ammonia decomposition catalytic material systems is an important research direction in the field of hydrogen production. Summary of the Invention
[0005] The purpose of this application is to overcome the shortcomings of low activity, low stability and high cost of transition metal catalysts in existing ammonia decomposition hydrogen production technology, and to provide a transition metal catalyst with high activity and stability, its preparation method and application.
[0006] The transition catalyst provided in this application not only has high activity and good stability, but also has a simple preparation process, inexpensive and readily available raw materials, and low preparation cost, and has potential application prospects.
[0007] According to one aspect of this application, a rare earth zirconate-supported transition metal catalyst is provided, the catalyst comprising a support and an active component of a transition metal element supported on the support;
[0008] The carrier is selected from at least one of cerium zirconate, lanthanum zirconate, praseodymium zirconate, neodymium zirconate, samarium zirconate, europium zirconate, gadolinium zirconate, erbium zirconate, and yttrium zirconate;
[0009] The transition metal element active component is selected from at least one of iron, cobalt, and nickel.
[0010] In the catalyst, the mass of the transition metal element active component is 0.1% to 100% of the mass of the support, based on the mass of the transition metal element.
[0011] Optionally, the mass of the transition metal element active component is any value among 0.1%, 0.2%, 1%, 2%, 10%, 25%, 47%, 68%, 89%, and 100% of the carrier mass, or a range between any two of the above points.
[0012] According to another aspect of this application, a method for preparing the above-mentioned rare earth zirconate-supported transition metal catalyst is provided, comprising the following steps:
[0013] The support is immersed in a solvent solution containing a transition metal element precursor, dried, ground, calcined, and reduced to obtain the rare earth zirconate-supported transition metal catalyst.
[0014] The transition metal element precursor is selected from at least one of the following: ferric chloride, cobalt chloride, nickel chloride, ferric carbonyl, cobalt carbonyl, nickel carbonyl, ferric nitrate, cobalt nitrate, nickel nitrate, ferric acetate, cobalt acetate, nickel acetate, ferric sulfate, cobalt sulfate, nickel sulfate, ferric iodide, cobalt iodide, nickel iodide, ferric fluoride, cobalt fluoride, and nickel fluoride.
[0015] The solvent is selected from at least one of water, ethanol, and acetone;
[0016] In the solvent solution containing the transition metal element precursor, the concentration of the transition metal element precursor is 0.0001 to 6 g / ml.
[0017] The solid-liquid ratio of the carrier to the solvent solution containing the transition metal element precursor is 1g:1-20ml.
[0018] Optionally, the solid-liquid ratio of the carrier to the solvent solution containing the transition metal element precursor is any value among 1g:1ml, 1g:5ml, 1g:10ml, 1g:15ml, 1g:20ml, or a range between any two of the above.
[0019] The impregnation temperature is 10–80°C;
[0020] Optionally, the immersion temperature is any value among 10℃, 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, and 80℃, or a range between any two of the above points.
[0021] The soaking time is 0.1 to 48 hours;
[0022] Optionally, the immersion time is any value among 0.1h, 0.5h, 1h, 2h, 4h, 8h, 16h, 32h, and 48h, or a range between any two of the above points.
[0023] The drying temperature is 10–200°C;
[0024] Optionally, the drying temperature is any value among 10℃, 50℃, 100℃, 150℃, and 200℃, or a range between any two of the above points.
[0025] The drying time is 1 to 48 hours.
[0026] Optionally, the drying time is any value among 1h, 2h, 4h, 8h, 16h, 32h, and 48h, or a range between any two of the above.
[0027] The roasting temperature is 100–1100°C;
[0028] Optionally, the roasting temperature is any value among 100℃, 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, 800℃, 900℃, 1000℃, and 1100℃, or a range between any two of the above points.
[0029] The roasting time is 0.1 to 48 hours;
[0030] Optionally, the roasting time is any value among 0.1h, 0.5h, 1h, 2h, 4h, 8h, 16h, 32h, and 48h, or a range between any two of the above.
[0031] The roasting atmosphere is a nitrogen atmosphere or an air atmosphere.
[0032] The volume hourly space velocity of the calcining atmosphere is 100–10000 h⁻¹. -1 .
[0033] Optionally, the volume hourly space velocity (VHSV) of the calcining atmosphere is 100 h⁻¹. -1 500h -1 1000h -1 5000h -1 10000h -1Any value in the range or any two points mentioned above.
[0034] The reducing atmosphere is a mixed atmosphere containing hydrogen and / or ammonia.
[0035] In the mixed atmosphere, the volume fraction of hydrogen and / or ammonia is 1 to 100%.
[0036] The volume hourly space velocity of the mixed atmosphere is 100–10000 h⁻¹. -1 ;
[0037] Optionally, the volume hourly space velocity of the mixed atmosphere is 100 h⁻¹. -1 500h -1 1000h -1 5000h -1 10000h -1 Any value in the range or any two points mentioned above.
[0038] The reduction temperature is 50–850°C;
[0039] Optionally, the reduction temperature is any value among 50℃, 100℃, 200℃, 400℃, 800℃, and 850℃, or a range between any two of the above points.
[0040] The reduction time is 0.1 to 48 hours.
[0041] Optionally, the restoration time is any value among 0.1h, 0.5h, 1h, 2h, 4h, 8h, 16h, 32h, and 48h, or a range between any two of the above points.
[0042] According to another aspect of this application, a method for ammonia decomposition is provided, comprising the following steps:
[0043] The raw gas containing ammonia is contacted with a catalyst to react and produce a product containing hydrogen and nitrogen.
[0044] The catalyst is the aforementioned rare earth zirconate-supported transition metal catalyst.
[0045] The ammonia content in the raw gas is 0.1% to 100% by volume.
[0046] The space velocity of the feed gas is 1000–100000 mL g. cat -1 h -1 ;
[0047] Optionally, the space velocity of the feed gas is 1000 mL g. cat -1 h -1 5000mL gcat -1 h -1 10000mL g cat -1 h -1 50000mL g cat -1 h -1 100000mL g cat -1 h -1 Any value in the range or any two points mentioned above.
[0048] The reaction temperature is 300–800°C;
[0049] Optionally, the temperature of the reaction is any value among 300℃, 400℃, 500℃, 600℃, 700℃, and 800℃, or a range between any two of the above points.
[0050] The reaction is carried out at a pressure of 0.1–10 MPa.
[0051] Optionally, the pressure of the reaction is any value among 0.1 MPa, 1 MPa, 5 MPa, and 10 MPa, or a range between any two of the above points.
[0052] The reaction apparatus is a fixed-bed reactor or a fluidized-bed reactor.
[0053] The beneficial effects that this application can produce include:
[0054] 1. High activity and stability: The catalytic material provided in this application exhibits high ammonia decomposition activity and stability under low pressure, low temperature and high space velocity in the application of catalytic ammonia decomposition, thus broadening the ammonia decomposition catalytic material system.
[0055] 2. Cost reduction: The catalytic material provided in this application achieves higher ammonia decomposition activity with lower transition metal usage compared to traditionally reported catalysts, resulting in a significant cost reduction.
[0056] 3. Simple preparation: The preparation method of the catalytic material provided in this application uses the conventional impregnation method, which is simple, uses inexpensive and readily available raw materials, has low preparation cost, and is easy to scale up for production. Detailed Implementation
[0057] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0058] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.
[0059] Example 1
[0060] Weigh 0.066 g of nickel chloride and dissolve it in 3 mL of acetone. Then add 1.00 g of yttrium zirconate to the nickel chloride-acetone solution and impregnate at 28 °C for 15 hours. After drying the product at 70 °C for 12 hours, it is then subjected to a nitrogen atmosphere (2000 h) for further processing. -1 The temperature was raised to 600℃ and calcined for 2 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 20% H2 / Ar mixed gas for 2000 hours. -1 The catalyst was reduced at 600℃ for 2 hours to obtain 3% Ni / Y2Zr2O7 supported on a yttrium zirconate catalyst, labeled as 1#.
[0061] Example 2
[0062] Weigh 0.44 g of cobalt chloride and dissolve it in 3 mL of ethanol. Then add 1.00 g of cerium zirconate to the cobalt chloride ethanol solution and impregnate at 10 °C for 48 hours. After drying the product at 180 °C for 2 hours, it is then subjected to an argon gas flow for 200 hours. -1 The temperature was raised to 900℃ and calcined for 0.5 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 3% H2 / N2 mixture for 1000 hours. -1 The catalyst was reduced at 700℃ for 0.5 hours to obtain a 20% Co / Ce2Zr2O7 transition metal catalyst supported on cerium zirconate, labeled as 2#.
[0063] Example 3
[0064] Weigh 2.90 g of ferric chloride and dissolve it in 3 mL of water. Then add 1.00 g of lanthanum zirconate to the ferric chloride aqueous solution and impregnate at 80 °C for 1 hour. After drying the product at 135 °C for 16 hours, it is then subjected to an argon flow (8000 h). -1 The temperature was raised to 950℃ and calcined for 48 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 60% H2 / N2 mixture for 4000 hours. -1 The catalyst was reduced at 850℃ for 7 hours to obtain 100% Fe / La2Zr2O7 lanthanum zirconate supported transition metal catalyst, labeled as 3#.
[0065] Example 4
[0066] Weigh 0.23 g of cobalt carbonyl and dissolve it in 10 mL of acetone. Then add 1.00 g of neodymium zirconate to the cobalt carbonyl acetone solution and impregnate at 55 °C for 5 hours. After drying the product at 10 °C for 48 hours, it is then subjected to an argon gas flow (10000 h). -1 The temperature was raised to 750℃ and calcined for 3 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 45% H2 / N2 mixture for 2000 hours. -1 The catalyst was reduced at 600℃ for 6 hours to obtain 8% Co / Nd2Zr2O7 supported on neodymium zirconate, labeled as 4#.
[0067] Example 5
[0068] 0.16 g of nickel nitrate was dissolved in 3 mL of acetone, and then 1.00 g of samarium zirconate was added to the nickel nitrate-acetone solution. The mixture was impregnated at 30 °C for 18 hours. The product was dried at 160 °C for 12 hours, and then subjected to an argon gas flow (2600 h). -1 The temperature was raised to 650℃ and calcined for 2 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 70% H2 / N2 mixture for 3900 hours. -1 The catalyst was reduced at 500℃ for 5 hours to obtain a 5% Ni / Sm2Zr2O7 transition metal catalyst supported on samarium zirconate, labeled as 5#.
[0069] Example 6
[0070] Weigh 1.20 g of nickel acetate and dissolve it in 8 mL of ethanol. Then add 1.00 g of yttrium zirconate to the nickel acetate ethanol solution and impregnate at 60 °C for 18 hours. After drying the product at 100 °C for 10 hours, it is then subjected to an argon gas flow for 3000 hours. -1 The temperature was raised to 800℃ and calcined for 4 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 35% H2 / N2 mixture for 1000 hours. -1 The catalyst was reduced at 600℃ for 22 hours to obtain 40% Ni / Y2Zr2O7 supported on a transition metal zirconate, labeled as 6#.
[0071] Example 7
[0072] Weigh 0.39 g of cobalt sulfate and dissolve it in 10 mL of water. Then add 1.00 g of gadolinium zirconate to the cobalt sulfate aqueous solution and impregnate at 50 °C for 21 hours. After drying the product at 80 °C for 30 hours, it is then subjected to an argon flow (8000 h). -1 The temperature was raised to 720℃ and calcined for 4 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 25% H2 / N2 mixture for 3000 hours. -1 The catalyst was reduced at 600℃ for 4 hours to obtain a 30% Co / Gd2Zr2O7 gadolinium zirconate-supported transition metal catalyst, labeled as 7#.
[0073] Comparative Example 1
[0074] 0.066 g of nickel chloride was dissolved in 3 mL of acetone, and then 1.00 g of zirconium oxide was added to the nickel chloride acetone solution. The mixture was impregnated at 28 °C for 15 hours. The product was dried at 70 °C for 12 hours, and then subjected to a nitrogen atmosphere (2000 h) for further processing. -1 The temperature was raised to 600℃ and calcined for 2 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 20% H2 / Ar mixed gas for 2000 hours. -1The alumina-supported transition metal catalyst 3% Ni / ZrO2 was obtained by reduction at 600℃ for 2 hours, and labeled as 8#.
[0075] Comparative Example 2
[0076] 0.066 g of nickel chloride was dissolved in 3 mL of acetone, and then 1.00 g of lanthanum oxide was added to the nickel chloride acetone solution. The mixture was impregnated at 28 °C for 15 hours. The product was dried at 70 °C for 12 hours, and then subjected to a nitrogen atmosphere (2000 h) for further processing. -1 The temperature was raised to 600℃ and calcined for 2 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 20% H2 / Ar mixed gas for 2000 hours. -1 The catalyst was reduced at 600℃ for 2 hours to obtain 3% Ni / La2O3 lanthanum oxide supported on a transition metal catalyst, labeled as 9#.
[0077] Comparative Example 3
[0078] Weigh 0.066 g of cobalt chloride and dissolve it in 3 mL of acetone. Then add 1.00 g of SBA-15 to the cobalt chloride-acetone solution and impregnate at 28 °C for 15 hours. After drying the product at 70 °C for 12 hours, it is then subjected to a nitrogen atmosphere (2000 h). -1 The temperature was raised to 600℃ and calcined for 2 hours to obtain the catalyst precursor. The catalyst precursor was then subjected to a 20% H2 / Ar mixed gas for 2000 hours. -1 The catalyst was reduced at 600℃ for 2 hours to obtain 3% Co / SBA-15 supported on a transition metal catalyst, labeled as 10#.
[0079] Application Example 8: Ammonia Decomposition Catalytic Performance Test
[0080] The reactor is a fixed-bed reactor with a quartz tube inner diameter of 6 mm. 100 mg of the reduced catalyst was used, the ammonia gas flow rate was 50 mL / min, and the reaction space velocity was 30000 mL gcat. -1 h -1 Its catalytic performance was tested at 1 atm and 550℃. The reaction gas was pure NH3. The results of the ammonia decomposition catalytic performance of some samples are shown in Table 1.
[0081] Table 1. Comparison of ammonia synthesis activities of different catalysts and ammonia synthesis reaction conditions
[0082]
[0083]
[0084] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A rare-earth zirconate-supported transition metal catalyst, characterized in that, The catalyst is composed of a support and an active component of a transition metal element supported on the support; The carrier is selected from at least one of cerium zirconate, lanthanum zirconate, praseodymium zirconate, neodymium zirconate, samarium zirconate, europium zirconate, gadolinium zirconate, erbium zirconate, and yttrium zirconate; The transition metal element active component is selected from at least one of iron, cobalt, and nickel. In the catalyst, the mass of the transition metal element active component is 0.1% to 100% of the mass of the support, based on the mass of the transition metal element.
2. A method for preparing a rare earth zirconate-supported transition metal catalyst as described in claim 1, characterized in that, Includes the following steps: The support is immersed in a solvent solution containing a transition metal element precursor, dried, calcined, and reduced to obtain the rare earth zirconate-supported transition metal catalyst.
3. The preparation method according to claim 2, characterized in that, The transition metal element precursor is selected from at least one of the following: ferric chloride, cobalt chloride, nickel chloride, ferric carbonyl, cobalt carbonyl, nickel carbonyl, ferric nitrate, cobalt nitrate, nickel nitrate, ferric acetate, cobalt acetate, nickel acetate, ferric sulfate, cobalt sulfate, nickel sulfate, ferric iodide, cobalt iodide, nickel iodide, ferric fluoride, cobalt fluoride, and nickel fluoride. The solvent is selected from at least one of water, ethanol, and acetone; In the solvent solution containing the transition metal element precursor, the concentration of the transition metal element precursor is 0.0001 to 6 g / ml.
4. The preparation method according to claim 2, characterized in that, The solid-liquid ratio of the carrier to the solvent solution containing the transition metal element precursor is 1g:1-20ml.
5. The preparation method according to claim 2, characterized in that, The impregnation temperature is 10–80°C; The soaking time is 0.1 to 48 hours; The drying temperature is 10–200°C; The drying time is 1 to 48 hours.
6. The preparation method according to claim 2, characterized in that, The roasting temperature is 100–1100℃; The roasting time is 0.1 to 48 hours; The roasting atmosphere is a nitrogen atmosphere or an air atmosphere. The volume hourly space velocity of the calcining atmosphere is 100–10000 h⁻¹. -1 .
7. The preparation method according to claim 2, characterized in that, The reducing atmosphere is a mixed atmosphere containing hydrogen and / or ammonia. In the mixed atmosphere, the volume fraction of hydrogen and / or ammonia is 1 to 100%. The volume hourly space velocity of the mixed atmosphere is 100–10000 h⁻¹. -1 ; The reduction temperature is 50–850°C; The reduction time is 0.1 to 48 hours.
8. A method for ammonia decomposition, characterized in that, Includes the following steps: The raw gas containing ammonia is contacted with a catalyst to react and produce a product containing hydrogen and nitrogen. The catalyst is the rare earth zirconate-supported transition metal catalyst as described in claim 1.
9. The method according to claim 8, characterized in that, The ammonia content in the raw gas is 0.1% to 100% by volume. The space velocity of the feed gas is 1000–100000 mL g. cat -1 h -1 ; The reaction temperature is 300–800°C; The reaction is carried out at a pressure of 0.1–10 MPa.
10. The method according to claim 8, characterized in that, The reaction apparatus is a fixed-bed reactor or a fluidized-bed reactor.