Environmental Engineering Reference
In-Depth Information
Table 5.1
Boiling point of alcohols, esters, and nitro compounds (
°
C)
Alkyl
Alcohols
Nitrate esters
Nitrous esters
Nitro groups
Methyl
65
65
−
12
101
Ethyl
78
88
17
114
N-propyl
96
111
47
131
Isopropyl
82
102
45
120
N-butyl
117
136
75
151
Table 5.2
The physical constants of nitrate esters
Compounds
e
20
n
20
1
d
20
4
g
20
N-butyl nitrate
13.10
1.39526
1.0156
0.87
Glycol dinitrate
28.26
1.43235
1.4918
4.61
1,3-propylene glycol dinitrate
18.97
1.43476
1.3952
5.8
1,2-propylene glycol dinitrate
26.80
1.42720
1.3774
4.65
1,3-butanediol glycol dinitrate
18.85
1.43259
1.3167
6.00
2,3-butanediol glycol dinitrate
28.84
1.42754
1.3061
4.7
Nitroglycerine
19.25
1.45731
1.5931
37.8
3-chloro-1,2-propylene glycol dinitrate
17.50
1.45850
1.5323
12.4
1,3-dichloro-2-propylene glycol dinitrate
13.28
1.46032
1.4630
4.8
Tribromopropane
6.45
1.56190
2.4360
Glycerol triacetate
7.19
1.410929
1.1596
Thus, nitrate esters have higher vapor pressure and are easier to be volatilized than
the corresponding alcohols.
The physical constants of nitrate esters, such as dielectric constants
e
20
, refrac-
tive index n
20
1
, density d
2
4
, and viscosity
g
20
, have been measured [
3
,
17
]. Those
constants are listed in the Table
5.2
.
The data of tribromopropane and glycerol triacetate are listed in the Table
5.2
for
the comparison with the corresponding derivatives.
The difference of viscosity among analogue compounds of 1,3-propylene glycol
dinitrate, 1,2-propylene glycol dinitrate, 1,3-butanediol glycol dinitrate, and 2,3-
butanediol glycol dinitrate is due to the optical isomerism. Anomers, which should
have higher viscosity, would be formed because of free rotation. This explanation
supports that the viscosity of 1,3-propylene glycol dinitrate and 1,3-butanediol
glycol dinitrate are higher than the other nitrate esters.
With increasing studies and knowledge to nitrate esters [
3
,
18
], more physical
constants of nitroglycerine and some glycol dinitrates have been obtained, as listed
in Table
5.3
.
