Environmental Engineering Reference
In-Depth Information
Molecular weight: 61.04
Oxygen balance:
39.3 % (calculated according to the produced CO
2
)
Content of nitrogen: 23 %
−
Nitromethane (NM) is a colorless and transparent liquid explosive with aromatic
odor, a relative density of 1.1376, boiling point of 101.2
°
C, freezing point of
C (open cup) and refractive index of 1.3818
20
.Itis
soluble in water, ethanol and basic solution, and its aqueous solution is acidic.
Nitromethane is miscible with many organic matters to form azeotrope liquid. Itself
is a good solvent and can be thickened after a small amount of nitrocellulose is
added. Additionally, concentrated acid can decompose into nitromethane into
ammonia, hydroxylamine and carbon oxides.
Further treatment with a base can generate a nitro acetic acid. At 50
28.55
°
C,
fl
flash point of 43
°
−
C, nitro-
methane was added dropwise into 50 % sodium hydroxide solution, followed by
boiling and cooling, nitro sodium acetate can be obtained, which can be turned into
nitro acetic acidwith hydrogen chloride gas going through the suspended ether system.
°
H
2
SO
4
thick
ð
Þ
CH
3
NO
2
!
HCOOH
þ
NH
2
OH
H
2
SO
4
þ
H
2
O
HCOOH
!
CO + H
2
O
H
2
SO
4
thick
ð
Þ
NH
3
þ
!
CH
3
NO
2
H
2
O
Nitromethane are particularly sensitive to base, and the reaction with base is
different from that of other nitroalkanes, hydrazone acid can be formed through
condensation reaction at low temperature (40
50
°
C).
-
-H
2
O
H
2
O
2
N-CH
2
-CH
2
NO
2
CH
2
=NO
2
H
ON-CH
2
-CH
2
-NO
2
HO-N=CH-CH
2
-NO
2
4.3.1.2 Thermal and Explosion Properties of Nitromethane
Standard heat of formation:
112.97 kJ/mol or
1850.75 J/g
−
−
Heat of combustion:
709.17 kJ/mol or
11618.1 J/g
−
−
Standard Gibbs free energy:
14.4 kJ/mol
−
Entropy: 171.8 kJ/mol
Heat capacity: 106.6 kJ/mol
Explosion limit: the low limit is 7.3 % (volume)
Explosion velocity: 6,320 m/s (
= 1.13 g/cm
3
)
q
Explosion heat: 4539.6 J/g
Explosion volume: 1,092 mL/g
Speci
c volume: 936 cm
3
/g
Explosion enthalpy:
5150 J/g
−
Explosion point: 420
°
C
TNT equivalent: 470 mL
