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EP-4737002-A1 - AMMONIA PARTIAL OXIDATION-BASED HYDROGEN EXTRACTION CATALYST AND HYDROGEN EXTRACTION METHOD

EP4737002A1EP 4737002 A1EP4737002 A1EP 4737002A1EP-4737002-A1

Abstract

Disclosed are an ammonia partial oxidation-based hydrogen extraction catalyst, a manufacturing method therefor, and a hydrogen extraction method using the catalyst. The ammonia partial oxidation-based hydrogen extraction catalyst comprises: a support; and ruthenium (Ru) loaded on the support. The hydrogen extraction method using the catalyst allows the temperature inside a reactor to be maintained at a high temperature without an external heat source and has a long reaction time, thereby solving the existing problem of thermal efficiency reduction and enabling a high ammonia conversion rate to be obtained.

Inventors

  • YOON, CHANG WON
  • KIM, JOON SEONG
  • HAN, Seungmok

Assignees

  • POSCO Holdings Inc.
  • POSTECH Research and Business Development Foundation

Dates

Publication Date
20260506
Application Date
20240613

Claims (19)

  1. A catalyst comprising: a support including a compound represented by the following Chemical Formula 1; and ruthenium (Ru) loaded on the support: [Chemical Formula 1] Ce 1-x M x O 2-δ wherein x satisfies 0<x<1, M is a lanthanide metal or a transition metal, and δ satisfies 0<δ≤0.5.
  2. The catalyst of claim 1, wherein the lanthanide metal includes one or more selected from the group consisting of lanthanum (La), samarium (Sm), ytterbium (Yb), gadolinium (Gd), and lutetium (Lu).
  3. The catalyst of claim 1, wherein the lanthanide metal includes lanthanum (La).
  4. The catalyst of claim 1, wherein the lanthanide metal includes lanthanum (La), and x satisfies 0.05≤x≤0.8.
  5. The catalyst of claim 1, wherein the transition metal includes one or more selected from the group consisting of zirconium (Zr), yttrium (Y), iron (Fe), copper (Cu), nickel (Ni), cobalt (Co), and osmium (Os).
  6. The catalyst of claim 1, wherein the transition metal includes zirconium (Zr).
  7. The catalyst of claim 1, wherein the transition metal includes zirconium (Zr), and x satisfies 0.05≤x≤0.5.
  8. The catalyst of claim 1, wherein the catalyst includes 1 to 5 wt% of the ruthenium.
  9. The catalyst of claim 8, wherein the catalyst includes 1.5 to 3.5 wt% of the ruthenium.
  10. The catalyst of claim 1, wherein the catalyst is for extracting hydrogen by decomposing ammonia.
  11. A manufacturing method for a catalyst, the method comprising: (a) preparing a precursor solution including one or more selected from the group consisting of lanthanide metal precursors and transition metal precursors, a cerium precursor, and water; (b) coprecipitating the precursor of the precursor solution to synthesize a coprecipitate including one or more selected from the group consisting of lanthanide metals and transition metals and cerium; (c) heat treating the coprecipitate to prepare a support; and (d) stirring a support solution including the support, the ruthenium precursor, and water to manufacture a catalyst including a ruthenium-loaded support.
  12. The manufacturing method for a catalyst of claim 11, wherein the catalyst includes a support including a compound represented by the following Chemical Formula 1 and ruthenium (Ru) loaded on the support: [Chemical Formula 1] Ce 1-x M x O 2-δ wherein x satisfies 0<x<1, M is a lanthanide metal or a transition metal, and δ satisfies 0<δ≤0.5.
  13. A hydrogen extraction method comprising: (1) extracting hydrogen by partially oxidizing ammonia in the presence of the catalyst of claim 11 and oxygen.
  14. The hydrogen extraction method of claim 13, wherein the partial oxidation reaction includes an ammonia decomposition reaction and an ammonia oxidation reaction.
  15. The hydrogen extraction method of claim 14, wherein the partial oxidation reaction is performed by a reaction of the following Reaction Formula 1: [Reaction Formula 1] NH 3 (g) + xO 2 (g) → 0.5N 2 (g)+ 2xH 2 O(g) + (1.5-2x)H 2 (g) H = 46-484x kJ mol -1 wherein x satisfies 0<x<0.75.
  16. The hydrogen extraction method of claim 15, wherein the reaction of Reaction Formula 1 is performed using heat of reaction by an exothermic reaction of one or more selected from the group consisting of the following Reaction Formula 2 and Reaction Formula 3 and some external heat sources: [Reaction Formula 2] NH 3 (g) → 0.5N 2 (g) + 1.5H 2 (g) △H = 45.9 kJ mol -1 [Reaction Formula 3] NH 3 (g) + 0.750 2 (g) → 0.5N 2 (g) + 1.5H 2 O(g) △H = -317 kJ mol -1 .
  17. The hydrogen extraction method of claim 13, wherein (1) is performed without supplying heat from outside or using some external heat sources.
  18. The hydrogen extraction method of claim 13, wherein in (1), a Gas Hour Space Velocity (GHSV, L/(g cat -h)) ratio between ammonia and oxygen is 2:1 to 6:1.
  19. The hydrogen extraction method of claim 13, wherein (1) is performed at 450 to 700°C.

Description

Technical Field The present disclosure relates to an ammonia partial oxidation-based hydrogen extraction catalyst, a manufacturing method therefor, and a hydrogen extraction method using the catalyst. Background Art Due to the problems of depletion and environmental pollution caused by indiscreet use of fossil fuels, various studies are being conducted on the production and utilization of renewable alternative energy which may replace fossil fuels, among them, in particular, hydrogen. Among various production methods of hydrogen, a method of extracting hydrogen by decomposing ammonia has benefits such as a high hydrogen storage capacity relative to weight (about 17.6 wt% H2), high energy density to volume (about 12.8 GJ/m3, 120 Kg-H2/m3), ease of liquefaction (0.8 MPa, 20°C or 0.1 MPa, - 33°C), and no CO2 emissions after decomposition as a hydrogen carrier, of ammonia. For reference, an ammonia decomposition reaction is as follows:         [Reaction Formula 1]      NH3(g) → 0.5N2(g) + 1.5H2(g) (H =+46 KJ/mol) However, the reaction is an endothermic reaction, of which the activation energy is also about ΔH=+117 KJ/mol, and thus, an external heat supply is essential. Therefore, in order for a temperature inside a reactor to be adjusted to 500°C or higher, heat of combustion of carbon-based fuels such as natural gas is used, and in this process, the thermal efficiency of the entire system is decreased due to the use of the carbon-based fuel for maintaining the temperature of 500°C or higher. Accordingly, development of a new ammonia decomposition hydrogen extraction system which does not require an external heat source, has a long reaction time, and may maintain the temperature inside a reactor at a high level, and a catalyst for realizing the system, appears to be important. Summary of Invention Technical Problem An aspect of the present disclosure is to provide an ammonia partial oxidation-based hydrogen extraction catalyst and system which do not require an external heat source. Another aspect of the present disclosure is to provide an ammonia partial oxidation-based hydrogen extraction catalyst and system which have a long reaction time and maintain the temperature inside a reactor high to solve a thermal efficiency reduction problem. Another aspect of the present disclosure is to provide a manufacturing method for the ammonia partial oxidation-based hydrogen extraction catalyst. Solution to Problem According to an aspect of the present disclosure, a catalyst includes: a support including a compound represented by the following Chemical Formula 1; and ruthenium (Ru) loaded on the support:         [Chemical Formula 1]     Ce1-xMxO2-δ wherein x satisfies 0<x<1, M is a lanthanide metal or a transition metal, and δ satisfies 0<δ≤0.5. In addition, the lanthanide metal may include one or more selected from the group consisting of lanthanum (La), samarium (Sm), ytterbium (Yb), gadolinium (Gd), and lutetium (Lu). In addition, the lanthanide metal may include lanthanum (La). In addition, the lanthanide metal may include lanthanum (La), wherein x satisfies 0.05≤x≤0.8, preferably 0.1≤x≤0.7, and more preferably 0.3≤x≤0.6. In addition, the transition metal may include one or more selected from the group consisting of zirconium (Zr), yttrium (Y), iron (Fe), copper (Cu), nickel (Ni), cobalt (Co), and osmium (Os). In addition, the transition metal may include zirconium (Zr). In addition, the transition metal may include zirconium (Zr), and x may satisfy 0.05≤x≤0.5, preferably 0.1≤x≤0.4 In addition, the catalyst may include 1 to 3 wt%, preferably 1.3 to 2.0 wt% of the ruthenium. Herein, less than 1 wt% of the ruthenium is not preferred, since the ammonia partial oxidation-based hydrogen extraction may not occur, and more than 3 wt% of ruthenium is not preferred, since ammonia decomposition efficiency is low. In addition, the catalyst may be for extracting hydrogen by decomposing ammonia. According to another aspect of the present disclosure, a manufacturing method for a catalyst includes: (a) preparing a precursor solution including one or more selected from the group consisting of lanthanide metal precursors and transition metal precursors, a cerium precursor, and water; (b) coprecipitating the precursor of the precursor solution to synthesize a coprecipitate including one or more selected from the group consisting of lanthanide metals and transition metals and cerium; (c) heat treating the coprecipitate to prepare a support; and (d) stirring a support solution including the support, the ruthenium precursor, and water to manufacture a catalyst including a ruthenium-loaded support. In addition, the catalyst may include a support including a compound represented by the following Chemical Formula 1 and ruthenium (Ru) loaded on the support:         [Chemical Formula 1]     Ce1-xMxO2-δ wherein x satisfies 0<x<1, M is a lanthanide metal or a transition metal, and δ satisfies 0<δ≤0.5. In addition, a pH of the precursor solu