An Improvement in the Treatment of Nitrated Cellulose for the Manufacture of Explosive and other Compounds containing Dissolved Nitrated Cellulose.
Year: 1892

page_text: Date of Application, 17th Nov., 1892.
Complete Specification Left, 16th Aug., 1893-Accepted, 23rd Sept., 1893
PROVISIONAL SPECIFICATION.
An Improvement in the Treatment of Nitrated Cellulose for the
Manufacture of Explosive and other Compounds containing
Dissolved Nitrated Cellulose.
I ARTHUR HAMILTON DURNFORD of The Cottage, Dartford, and of The
Conservative Club, Dartford, in the County of Kent, Gentleman, do hereby declare
the nature of this invention to be as follows:-
My invention has for its object to obviate the necessity of drying nitrated
cellulose before dissolving it for the purpose of making explosive and other
compounds containing dissolved nitrated cellulose and thereby to avoid the danger
attending such drying process.
In the manufacture of cordite, blasting gelatine, and other similar explosives,
and other compounds containing dissolved nitrated cellulose, it, has heretofore
been necessary that the nitrated cellulose be first dried in order that it may be
dissolved by a suitable solvent because, if the nitrated cellulose be treated there-
with when in its wet condition the power of the solvent for this particular purpose
is destroyed owing to the combination of the solvent with the water contained in
the wet nitrated cellulose.
The drying of the nitrated cellulose is usually effected by means of hot air in a
suitable stove and owing to its dangerous character the dried nitrated cellulose
must be stored for subsequent use in a building specially set apart for the purpose.
The operation of drying the tri-nitro-cellulose in particular and storing it in its
dry condition is attended with considerable danger.
I have discovered a method by which tri-nitro-cellulose or other nitrated cellulose
can be dissolved in its appropriate solvent, without it being first dried, whereby
the danger attendant on the drying operation is avoided and the special buildings
for the purpose of drying and storage are rendered unnecessary. In carrying my
said invention into practice I proceed as follows-
The wet tri-nitro-cellulose or other forms of nitrated cellulose is submitted to
pressure to squeeze out the excess of water and then soaked in what I term a
dehydrator, as for instance an alcohol or preferably a solvent of the nitrated
cellulose (in the case of tri-nitro-cellulose acetone is preferred). The temperature
of the mixture rises somewhat in consequence of the dehydrator abstracting and
combining with the water remaining in the nitrated cellulose after squeezing. The.
nitrated cellulose is stirred about in the dehydrator and left to soak until the
temperature somewhat subsides whereupon further pressure is applied to expel as
much as possible of the dehydrator used together with the water that it has
combined with. If the dehydrator which has been used be also a solvent for the
nitrated cellulose it will leave the latter in a putty like condition. This dehydrated
nitrated cellulose is then mixed with the solvent in which it is to be dissolved,
acetone being preferred in the case of tri-nitro-cellulose.
The consistency of the dissolved nitrated cellulose can be regulated by varying
the proportion of the solvent. The dehydrator which was expressed from the
nitrated cellulose as above mentioned can be used again after distillation to get rid
of the water which it has absorbed.
Dated this 17th day of November 1892
A. H. DURNFORD,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agente

page_text: COMPLETE SPECIFICATION:
An Improvement in the Treatment of Nitrated Cellulose for the
Manufacture of Explosive and other Compounds containing
Dissolved Nitrated Cellulose.
I, ARTHUR HAMILTON DURNFORD of The Cottage, Dartford, and of The
Conservative Club, Dartford, in the County of Kent, Gentleman, 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 object of my invention is to obviate the necessity of drying nitrated
cellulose before dissolving it for the purpose of making explosive and other
compounds containing dissolved nitrated cellulose.
In the manufacture of cordite, blasting gelatine, and other similar explosives
and other compounds containing dissolved nitrated cellulose, it has heretofore been
necessary to dry the nitrated cellulose before treating it with a suitable solvent.
The necessity for first drying the nitrated cellulose arises from the fact that if it
were treated when in its wet condition the water contained in the wet nitrated
cellulose would combine with the solvent and destroy its power for the purpose for
which it is used.
The drying of the nitrated cellulose is usually effected by means of hot air and
is attended with considerable danger, particularly in the case of tri-nitro-cellulose.
Owing to the dangerous character of the nitrated cellulose when in the dry state
its storage in that condition for subsequent use involves the 'employment of a
building specially set apart for the purpose.
I have discovered a method whereby it is unnecessary to dry tri-nitro-cellulose
or other nitrated cellulose before dissolving it in its appropriate solvent, so that
the danger attendant on drying and storage is avoided and the special buildings
now employed for those purposes are rendered unnecessary.
In carrying my said invention into effect I proceed as follows:-The tri-nitro-
cellulose or other form of nitrated cellulose in the wet state (in which it is usually
stored for use) is first submitted to pressure to expel as much as possible of the
water. It is then immersed in what I term a "dehydrator" which combines with
the water remaining in the nitrated cellulose. Nearly all the water is then carried
off with the dehydrator when the nitro-cellulose is again submitted to pressure to
expel the " "dehydrator."
66
The dehydrator may be an alcohol or preferably a solvent of the nitrated
cellulose, acetone being preferred in the case of tri-nitro-cellulose. A slight rise
of temperature occurs during the immersion of the nitrated cellulose in the
'dehydrator," in consequence of the latter combining with the water.. The
nitrated cellulose should therefore be stirred about in the "dehydrator" and left
to soak until the temperature somewhat subsides. After immersion for a sufficient
period, which is indicated by no continued increase of temperature, the nitrated
cellulose is removed from the dehydrator and again submitted to pressure in order
to expel therefrom as much as possible of the dehydrator which it has absorbed
and which on being expressed carries off along with it the water with which it has
combined. When there is much water in the wet nitro-cellulose, it is sometimes
necessary to treat it a second time. If the dehydrator used be also a solvent for
the nitrated cellulose it will leave the latter in a putty-like condition.
The dehydrated nitrated cellulose is then mixed with the solvent in which it is
to be completely dissolved, the consistency of the solution being regulated by
varying the proportion of the solvent. The dehydrator which has been expressed
from the nitrated cellulose, as above mentioned, can be freed from the water which
it has absorbed, by distillation and is then fit for use over again for dehydrating a
fresh batch of nitrated cellulose.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is-
The method of dissolving wet nitrated cellulose, which consists in first dehydrating
it by immersion in an alcohol or a solvent of the nitrated cellulose, then expressing
the dehydrating agent and combined water, and finally effecting the complete
solution of the dehydrated nitrated cellulose, as specified."
1000
A. H. DURNFORD,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.