Environmental Engineering Reference
In-Depth Information
Table 5.15
Speci
cation of
glycol in nitration reaction
[
27
]
Parameter
Value
Boiling point (
°
C)
196
200
-
Density (g/cm
3
)
1.1130
-
1.1135
Acidity (H
2
SO
4
-based %)
<0.1
Saponi
cation value (Na
2
O %)
<1.0
In industry, because of the accumulation of nitration heat, the reaction heat
usually exceeds the value obtained in laboratory scale. The main reaction mecha-
nism of nitration of glycol can be expressed as:
H
2
SO
4
C
2
H
4
(OH)
2
+HNO
3
C
2
H
4
(ONO
2
)
2
+H
2
O+355.64J/mol
Actually, the nitrate heat of the nitration reaction of glycol in industry is double
times higher than that in small scale. The reaction rate is as fast as only 1
-
1.5 s to
finish the nitration reaction when glycol is fully mixed with the mixed acid.
The writer [
15
] studied the in
uence of reaction conditions and the production
processes [
5
] of mixed acid injection nitration and air-agitated nitration. Those
processes were successfully applied in the industrial manufacture of glycol dini-
trate. The speci
fl
cation of glycol to produce glycol dinitrate is shown in Table
5.15
.
The nitration processes of glycol and glycerine are not the same because of the
difference of property of the raw materials and products. In the nitration process of
glycol, heat pretreatment is not necessary and the optimal nitration temperature is
10
C. Too high nitration temperature will cause low yield of products. The
process diagram of glycol dinitrate is shown in Fig.
5.9
.
Glycol of 100 kg can produce glycol dinitrate of 229.075 kg at 10
15
°
-
12
°
C, that is,
-
the theoretical yield is 93.5 %.
5.3.2 Property and Preparation of Diethylene Glycol
Dinitrate
5.3.2.1 Chemical Physical Properties
Molecular formula: C
4
H
8
N
2
0
7
Chemical structure:
H
H
H
H
O
2
N
O
C
C
O
C
C
O
NO
2
H
H
H
H
Molecular weight: 196.12
Oxygen balance:
40.8 % (CO
2
-based)
Nitrogen content: 14.28 %
−
