Irreversible reaction

Sodium azide from hydrazine, methyl nitrite and sodium hydroxide

Direction: Irreversible
Processes: 1
Stated as: Rate law
Heat of reaction: ΔH = -339,700 kJ/kmol (one process)
Element balance: Checked: balances

As the processes state itStoichiometry, conversions, heats of reaction and catalyst windows are taken from each process's files with their provenance. The build checks only that each process's equation balances in every element, from the process's own component formulas; it does not check the numbers. A process's design maturity applies to them.

Species

Species	Name	CAS	Role	Coefficient
N₂H₄	Hydrazine	302-01-2	reactant	-1
CH₃NO₂	Methyl nitrite	624-91-9	reactant	-1
NaOH	Sodium hydroxide	1310-73-2	reactant	-1
NaN₃	Sodium azide	26628-22-8	product	1
CH₄O	Methanol	67-56-1	product	1
H₂O	Water	7732-18-5	product	2

In the processes

Sodium azide by the hydrazine / methyl nitrite route, batch, with precipitation from the reaction liquor (670 t/a)Concept · not reviewed
AZ · Sodium azide from hydrazine, methyl nitrite and sodium hydroxideN2H4 + CH3ONO + NaOH → NaN3 + CH3OH + 2 H2O
Stated as
Rate law
Phase
liquid
Element balance
Balances in every element
Heat of reaction
ΔH = -339,700 kJ/kmol at 298.15 K, as written (assumed: 21.7 - 238.4 - 3 x 285.825 - (-242.57 - 66.1 - 425.8) kJ/mol: N2H4.H2O(l) + CH3ONO(g) + NaOH(s) -> NaN3(s) + CH3OH(l) + 3 H2O(l), pure-substance standard states (chemicals: ATcT, CRC, NIST WebBook); the dissolved hydrazine taken as its hydrate; heats of solution not counted, conservative by about 15-20 % (D-005))
Rate law
basis: volume; driving: concentration; form: power_law; k: {"A":"1.0200e7","Ea":60000}; orders: {"MEONO":1,"N2H4":1}; temperature range: 293.15 – 323.15 (assumed: ASSUMED effective rate (D-005): no open kinetics found (2026-11-05); about 4 min half-life of the dissolved methyl nitrite at the charge's hydrazine; to be replaced by reaction calorimetry)

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.

US 5 208 002 A (Nippon Carbide, 1993): claims and Examples 1-4, aqueous hydrazine (51.2 wt%) and 1.0-1.5 mol NaOH per mol hydrazine absorb gaseous methyl nitrite at 20-50 C, hydrazine conversion held at 50-90 % (examples 70 %), about 95 % selectivity
For the reaction · cited by Sodium azide by the hydrazine / methyl nitrite route, batch, with precipitation from the reaction liquor (670 t/a)
21.7 - 238.4 - 3 x 285.825 - (-242.57 - 66.1 - 425.8) kJ/mol: N2H4.H2O(l) + CH3ONO(g) + NaOH(s) -> NaN3(s) + CH3OH(l) + 3 H2O(l), pure-substance standard states (chemicals: ATcT, CRC, NIST WebBook); the dissolved hydrazine taken as its hydrate; heats of solution not counted, conservative by about 15-20 % (D-005)
For the heat of reaction · cited by Sodium azide by the hydrazine / methyl nitrite route, batch, with precipitation from the reaction liquor (670 t/a)