Ammonia oxidation to nitrogen (side reaction)

Species

In the processes

• Ammonia from natural gas (1500 t/d, steam reforming with air-fed secondary reformer, Haber-Bosch loop)Concept · not reviewed

  NH3_COMB4 NH3 + 3 O2 → 2 N2 + 6 H2O

  Scale

  Written at 0.25 times the scale

  Stated as

  Fixed conversion

  Element balance

  Balances in every element

  Conversion

  100 % of NH3 (given: design basis of complete combustion with excess air (owner's decision I-006, 2026-10-30, D-040): US EPA Method 19, 40 CFR Part 60 Appendix A-7, section 12.3.2.1, Eq. 19-13: the F factors count fuel nitrogen as N2 and fuel hydrogen as burnt to water (complete, stoichiometric combustion of the fuel's H, C, S, N and O); Schmitt (AFRC, ark:/87278/s6fc0529, pp. 1-6), as H2_COMB. The NH3 is 0.04 mol% of the furnace fuel (tail gas); the NOx formed from it is not modelled (I-07). Supporting evidence of the earlier S5b basis, kept: Lin et al. (2024), Experimental study on ammonia co-firing with coal for carbon reduction in the boiler of a 300-MW coal-fired power station, Engineering 40, doi:10.1016/j.eng.2024.06.003, abstract: NH3 below 1 ppm at the furnace outlet under all co-firing conditions; the NOx formed from it is not modelled (I-07, D-034). S5b fix r2: closer, still not this duty: Sharma et al. (2024), Flame behavior and emission characteristics of methane and ammonia fueled high-temperature flame in a bench-scale furnace, J. Therm. Sci. Technol. 19(2), 24-00063, doi:10.1299/jtst.24-00063, abstract: a gas-fired furnace on 30 % NH3 / 70 % CH4 (LHV basis), NH3 and N2O hardly detected at the exhaust; bench scale, air preheated to about 1000 C (E-106 preheats to 250 C), excess air not stated in the abstract)

• Hydroxylammonium sulfate by catalytic NO hydrogenation (30 kt/a NH2OH, 25 wt% solution)Concept · not reviewed

  NH3_N24 NH3 + 3 O2 → 2 N2 + 6 H2O

  Stated as

  Fixed conversion

  Element balance

  Balances in every element

  Conversion

  0.5969 % of NH3 (assumed: D-005: the remainder 1 - 0.98 - 0.014031 (US 3,110,563 names N2 and N2O as the rest; complete NH3 conversion ASSUMED))

  Catalyst

  Pt/Rh gauze

• Weak nitric acid by dual-pressure ammonia oxidation (1000 t/d HNO3 as 60 wt% acid)Concept · not reviewed

  NH3_N24 NH3 + 3 O2 → 2 N2 + 6 H2O

  Stated as

  Fixed conversion

  Element balance

  Balances in every element

  Conversion

  2.595 % of NH3 (assumed: D-005: the remainder 1 - 0.955 - 0.0190548 (complete NH3 conversion, ASSUMED))

  Catalyst

  Pt/Rh gauze

• Sodium nitrite from ammonia oxidation and soda absorption (with sodium nitrate by inversion)Concept · not reviewed

  NH3_N2 · Ammonia oxidation to nitrogen (side reaction)4 NH3 + 3 O2 → 2 N2 + 6 H2O

  Stated as

  Fixed conversion

  Element balance

  Balances in every element

  Conversion

  1.6 % of NH3 (assumed: D-005: the remainder 1 - 0.97 - 0.014 (complete NH3 conversion, ASSUMED))

  Catalyst

  Pt/Rh gauze (95/5)

Sources

What the processes cite for this reaction, each source once: for the reaction itself, its conversion, its heat of reaction or its catalyst. As the processes write them; DOIs, US patent numbers and web addresses are linked.

1. design basis of complete combustion with excess air (owner's decision I-006, 2026-10-30, D-040): US EPA Method 19, 40 CFR Part 60 Appendix A-7, section 12.3.2.1, Eq. 19-13: the F factors count fuel nitrogen as N2 and fuel hydrogen as burnt to water (complete, stoichiometric combustion of the fuel's H, C, S, N and O); Schmitt (AFRC, ark:/87278/s6fc0529, pp. 1-6), as H2_COMB. The NH3 is 0.04 mol% of the furnace fuel (tail gas); the NOx formed from it is not modelled (I-07). Supporting evidence of the earlier S5b basis, kept: Lin et al. (2024), Experimental study on ammonia co-firing with coal for carbon reduction in the boiler of a 300-MW coal-fired power station, Engineering 40, doi:10.1016/j.eng.2024.06.003, abstract: NH3 below 1 ppm at the furnace outlet under all co-firing conditions; the NOx formed from it is not modelled (I-07, D-034). S5b fix r2: closer, still not this duty: Sharma et al. (2024), Flame behavior and emission characteristics of methane and ammonia fueled high-temperature flame in a bench-scale furnace, J. Therm. Sci. Technol. 19(2), 24-00063, doi:10.1299/jtst.24-00063, abstract: a gas-fired furnace on 30 % NH3 / 70 % CH4 (LHV basis), NH3 and N2O hardly detected at the exhaust; bench scale, air preheated to about 1000 C (E-106 preheats to 250 C), excess air not stated in the abstract

   For the conversion · cited by Ammonia from natural gas (1500 t/d, steam reforming with air-fed secondary reformer, Haber-Bosch loop)

2. D-005: the remainder 1 - 0.98 - 0.014031 (US 3,110,563 names N2 and N2O as the rest; complete NH3 conversion ASSUMED)

   For the conversion · cited by Hydroxylammonium sulfate by catalytic NO hydrogenation (30 kt/a NH2OH, 25 wt% solution)

3. cheme chemistry library nitric_acid

   For the reaction · cited by Weak nitric acid by dual-pressure ammonia oxidation (1000 t/d HNO3 as 60 wt% acid)

4. D-005: the remainder 1 - 0.955 - 0.0190548 (complete NH3 conversion, ASSUMED)

   For the conversion · cited by Weak nitric acid by dual-pressure ammonia oxidation (1000 t/d HNO3 as 60 wt% acid)

5. D-005: the remainder 1 - 0.97 - 0.014 (complete NH3 conversion, ASSUMED)

   For the conversion · cited by Sodium nitrite from ammonia oxidation and soda absorption (with sodium nitrate by inversion)

Starter template

Templates bring the stoichiometry, the components and typical catalysts; most give no conversion or kinetics, and their sources are general references, not this reaction's processes.