Environmental Engineering Reference
In-Depth Information
50
120
°
C, the amount of sodium carbonate is 4.0
5.5 % (pH should be kept at
-
-
6.5
5.5 h, catalyst is tetrabutylam-
monium bromide, the amount of catalyst is 0.5 %, the water and methanol liquid
after nitromethane distillation is reused, the yield is 79.8 %, and the purity is
≥
7.5 during its addition), reaction time is 4.5
-
-
99.9 % (Table
4.7
).
Table 4.2 The relationship between the mass ration of dimethyl sulfate over sodium nitrite and
nitromethane
Dimethyl sulfate: sodium nitrite
1:0.5
1:0.75
1:1
1:1.25
1:1.5
1:1.75
1:2.0
Yield of nitromethane (%)
48.71
56.22
65.27
73.53
76.43
77.32
79.88
Table 4.3 Effects of temperature on the yield of nitromethane
Reaction temperature (
°
C)
25
35
45
55
65
75
85
95
Yield of nitromethane (%)
49.87
56.44
65.49
78.47
74.31
70.67
63.40
55.63
Table 4.4 Effects of reaction time on the yield of nitromethane
Reaction time (h)
1
1.5
2.5
3.5
4.5
5.5
6.5
8
Yield of nitromethane (%)
30.20
38.42
56.87
71.37
79.67
81.83
74.12
61.39
Table 4.5 Effects of dosage of tetrabutylammonium bromide on the yield of nitromethane
Dosage of tetrabutylammonium
bromide (%)
0.05
0.1
0.3
0.5
0.7
0.9
1.1
1.3
1.5
Yield of nitromethane (%)
49.7
59.2
71.6
80.3
79.1
82.6
87.8
89.7
91.3
Table 4.6 Effects of dosage of sodium carbonate on the yield of nitromethane
Dosage of
sodium carbonate
(%)
1.0
1.5
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
Yield of nitro-
methane (%)
40.3
49.8
56.2
61.6
89.7
84.6
86.3
59.1
53.7
49.9
44.6
