Improvements in the Manufacture of Safety-explosives.
Year: 1898

page_text: Date of Application, 29th Mar.,
1898
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Safety-explosives.
I, HANS RITTER VON DAHMEN, Chemist, of Canth, Schlesien, do hereby declare
the nature of this invention to be as follows:-
The numerous experiments made on mining explosives with a view to more
efficiently protecting the lives of those employed in the mining industry from
the dangerous effects of explosives used in the presence of coal-dust and fire-damp
and the experiences gathered from such experiments have led me to carefully
examine the behaviour of acetic acid, tartaric acid, citric acid and their salts
with a view to producing safety explosives therefrom.
The use of explosives of the ammonium nitrate group has proved more and
more, that they come nearest to an ideal safety-explosive!
It would however not appear practical to disregard safety explosives of the
nitroglycerine group, as for instance carbonite and "Wetterdynamite" i.e. fire-
damp-proof dynamite.
I have therefore also included these latter explosives in my experimental work
and will now explain the results obtained.
Thus, for instance I have found, that the acetic acid, tartaric acid and citric
acid of these acid groups which already on account of their relative cheapness
may find employment in the manufacture of explosives, greatly contribute to
increasing the safety of known explosives, whether used in their acid form or as
salts.
Taking for instance: Roburite consisting of
178 parts of dinitrobenzol
792 parts of ammonium nitrate
03 parts of salammoniac and ammonium sulphate } impurities.
27 parts of moisture
according to analysis undertaken in the Bochum Fire-damp Laboratory:
Even 173 grammes used in the presence of coal-dust and of a fire-damp mixture
of 2.4 per cent. have caused ignitions.
On the other hand a composition of
165 parts of dinitrobenzol
79. parts of ammonium nitrate
.45 parts of acetic acid
permits of 500 grammes being used in the presence of coal dust and of a fire-
damp mixture of 7 per cent. without an ignition taking place.
Ammonium nitrate explosives are all of a more or less hygroscopic nature,
and as the salts especially of acetic acids are for the greater part highly sensitive
to atmospheric agents, I have experimented on incorporating the acetic acid
(tartaric acid, citric acid) with the combinations of ammonium nitrate and carbon
compounds.
This is done either by dissolving the carbon compounds, which are soluble

page_text: in acetic acid, and by adding ammonium nitrate to the dissolved product; or
by forming a combination by mixing carbon compounds-which are capable of
uniting with comparatively large quantities of acetic acid-with any other carbon
compound, I wish to add to the explosive.
If, however, I
dissolve the resin in oleine and add to this product the acetic acid, the latter will
completely unite therewith.
Thus for instance acetic acid dissolves only traces of resin.
1
Thus, by using the respective combining agents, I am enabled to employ all
those carbon compounds which are of real and practical value in the manufac-
ture of explosives, for example, a compound of:
112 parts of dinitrobenzol.
855 parts of ammonium nitrate
14 parts of acetic acid, and
19 parts of oleine
is so safe, that 500 grammes exploded in the presence of coal-dust and of fire-
damp of an intensity of 7 per cent. will not result in ignition.
The acetic acid in combination with ammonium nitrate presents, however,
still another advantage, owing to its being an excellent solvent of the carbon
compounds and it so permeates the ammonium nitrate, that its hygroscopic
qualities are greatly reduced.
I have obtained these results not only with ammonium nitrate but observed
similar results with other nitrates. Whereas in the case of nitrates, which are
solid bodies, I employ acetic acid as an excellent solvent of carbon compounds,
I use, on the other hand, acetic salts in the case of liquid nitroglycerine, which
is insoluble in water.
I thus use, for example:
93 parts of nitroglycerine, and
7 parts of acetate of soda.
From this mixture I produce in the known manner: carbonite and. "Wetter-
dynamite" (fire-damp proof dynamite) and thereby obtain a product far safer
against the ignition of fire-damp and coal dust.
dail
P
1
1000
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.
Improvements in the Manufacture of Safety-explosives.
I, HANS RITTER VON DAHMEN, Chemist, of Canth, Schlesien, in the Empire of
Germany, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
-
The numerous experiments made on mining explosives with a view to more
efficiently protecting the lives of those employed in the mining industry from
the dangerous effects of explosives used in the presence of coal-dust and fire-damp
and the experiences gathered from such experiments have led me to carefully
examine the behaviour of acetic acid, tartaric acid, citric acid and their salts
with a view to producing safety explosives therefrom.
The use of explosives of the ammonium nitrate group has proved more and
more, that they come nearest to an ideal safety-explosive.
It would however not appear practical to disregard safety explosives of the
nitroglycerine group, as for instance carbonite and fire damp-proof dynamite.

page_text: I have therefore also included these latter explosives in my experimental work
and will now explain the results obtained.
Thus, for instance I have found, that the acetic acid, tartaric acid and citric
acid of these acid groups which already on account of their relative cheapness
may find employment in the manufacture of explosives, greatly contribute to
increasing the safety of known explosives, whether used in their acid form or as
11
55
Even 173 grammes used in the presence of coal-dust and of a pre-camp mixeq
of 2.4 per cent. have caused ignitions.
On the other hand a composition of
165 parts of dinitrobenzol
79. parts of ammonium nitrate
45 parts of acetic acid
permits of 500 grammes being used in the presence of coal dust and of a fire-
damp mixture of 7 per cent. without an ignition taking-place.
Ammonium nitrate explosives are all of a more or less hygroscopic nature.
and as the salts especially of acetic acids are for the greater part highly sensitive
to atmospheric agents, I have experimented on incorporating the acetic acid
(tartaric acid, citric acid) with the combinations of ammonium nitrate and carbon
compounds.
This is done either by dissolving the carbon compounds, which are soluble
in acetic acid, and by adding ammonium nitrate to the dissolved product; or
by forming a combination by mixing carbon compounds-which are capable of
uniting with comparatively large quantities of acetic acid--with any other carbon
compound, I wish to add to the explosive.
Thus for instance acetic acid dissolves only traces of resin. If, however, I
dissolve the resin in oleine and add to this product the acetic acid, the latter will
completely unite therewith.
Thus, by using the respective combining agents, I am enabled to employ all
those carbon compounds which are of real and practical value in the manufac-
ture of explosives, for example, a compound of:
112 parts of dinitrobenzol
855 parts of ammonium nitrate
14 parts of acetic acid, and
19 parts of oleine
is so safe, that 500 grammes exploded in the presence of coal-dust and of fire-
damp of an intensity of 7 per cent. will not result in ignition.
The acetic acid in combination with ammonium nitrate presents, however,
still another advantage, owing to its being an excellent solvent of the carbon
compounds and it so permeates the ammonium nitrate, that its hygroscopic
qualities are greatly reduced.
I have obtained these results not
similar results with other nitrates.
solid bodies, I employ acetic acid as
I use, on the other hand, acetic salts in the case of liquid nitroglycerine, which
is insoluble in water.
only with ammonium nitrate but observed
Whereas in the case of nitrates, which are
an excellent solvent of carbon compounds,
I thus use, for example:
93 parts of nitroglycerine, and
7 parts of acetate of soda.
From this mixture I produce in the known manner: Carbonite and fire-damp

page_text: proof dynamite, and thereby obtain a product far safer against the ignition of
fire-damp and coal dust.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed 1 declare that what
I claim is:
The use of acetic acid, tartaric acid, citric acid, or their salts and compounds
for producing safety explosives, that is to say explosives, not liable to ignite
coal-dust or fire-damp.
1
1
1000
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.