urbaf2

282 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

PHYSICAL PROPERTIES

All the isomers are pale yellow, crystalline products. The composition of the

eutectic formed by 2,4-dinitrotoluene with α− trinitrotoluene is given in Table 66

(p. 295).

The solubility of technical DNT (the mixture of isomers) in sulphuric acid

was given by Orlova [2a] (Table 55).

TABLE 55

SOLUBILITY OF TECHNICAL DNT IN SULPHURIC ACID

Concentration

% H 2 SO 4

80.0

83.6

88.7

90.0

93.0

99.8

Solubility: g of DNT

in 100 g of the acid at temperatures °C

20 40

1.2 -

• .3.6
  6.1 10.0
  8.5 -


• 26.4


• 72.6

50 70 100 120

2.5

4.7

12.8

16.8

33.8

14.4

3.8

6.3 6.4

20.0 -

58.3 82.4

1121 1360

6.5

17.4

• 66.6


• 
  

THERMOCHEMICAL PROPERTIES

According to Bichel [22] the heat of formation of 2,4-dinitrotoluene is

7.7 kcal/mole; Koehler [23] has reported it to be 5.9 kcal/mole.

Garner and Abernethy [3] give the following values for the heats of combustion

and heats of formation of the isomers (see also Fig. 50, p. 261).

The same authors have calculated the heat of nitration of mono- to di-nitrotoluene.

TABLB 56

HEATS OF COMBUSTION AND HEATS OF FORMATION OF THE DINITROTOLUENE ISOMERS

Dinitrotoluene

isomer

Heat of combustion

(at constant volume)

k&/mole

2,4-Dinitrotoluene 853.7

2,6-Dinitrotoluene 855.2

2.3-Dinitrotoluene 860.5

2,5-Dinitrotoluene 856.1

3,4-Dinitrotoluene 860.8

3,5-Dinitrotoluene 853.9

Heat of formation

kcal/mole

+31.3

+29.6

+24.3

+28.7

+24.0

+30.9