urbaf2

304 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

T. Urbaliski and Pawlowski [89] obtained the following characteristic values:

“T acid” ignites, when heated to

Sodium salt of “T acid” at

Copper salt of “T acid” at

Ferric salt of “T acid” at

Zinc salt of “T acid” at

210°C after 4 see

225°C ,, 0.5 ,,

185°C ,, 4 ,,

200°C ,, 0.5 ,,

210°C ,, 4 ,,

225°C ,, 0.8 ,,

220°C ,, 4.5 ,,

235°C ,, 0.6 ,,

230°C ,, 3.5 ,,

245°C ,, 0.8 ,,

“T acid”, when contacted with a flame, ignites instantaneously like dry nitro-

cellulose. Salts of “T acid” ignite just as readily. Its sensitivity to impact is also

very high, being of the same order as tetryl.

According to Bowden [91], the initiation temperature of the product of prolonged

treatment of TNT with moist ammonia (for 66 hr) is merely 67°C. This observa-

tion has not been confirmed by other authors, who found the initiation tempera-

ture of the product to be about 250°C, i.e. of the same order as that of TNT (290°C)

within the limits of experimental error. Even if not all authors agree with Bowden’s

low figure for the temperature of initiation of the products obtained by reacting

trinitrotoluene with alkalis, it has been stated repeatedly that these products are

much more sensitive to heat, impact and friction than trinitrotoluene itself. Their

high sensitiveness is of greatest practical importance, and is a warning that great

care should be taken to avoid bringing TNT into contact with alkalis, especially

in the presence of organic solvents such as alcohol, acetone etc.

There is evidence that the reaction product of trinitrotoluene with potassium

alcoholate, which explodes when heated to 130-150°C, may even ignite sponta-

neously at room temperature.

According to Dupre [92], the ignition temperature of trinitrotoluene is consid-

erably lowered by the addition of various substances, e.g. sulphur, phosphorus,

aniline black. When potassium hydroxide is added at 160°C, trinitrotoluene ignites

or explodes immediately. A mixture of powdered trinitrotoluene and powdered

potassium hydroxide ignites when heated to 80°C. A mixture with sodium hydroxide

behaves similarly although the reaction is less vigorous, On rapid heating, ignition

occurs at a temperature of 80°C but on slow heating the mixture does not explode;

even at 200°C - only gradual decomposition takes place.

When a piece of potassium hydroxide is put into molten trinitrotoluene at

100°C, it becomes coated with a film that prevents it from reacting further. But

on addition of a drop of alcohol, which dissolves both trinitrotoluene and potas-

sium hydroxide, the mixture ignites at once.

Reaction with inorganic substances

A. J. B. Robertson [66] investigated the influence of various substances on the

rate of thermal decomposition of trinitrotoluene. He measured the diminution