Process for the Manufacture of Smokeless Powder.
Year: 1898

page_text: Date of Application, 17th Feb., 1898-Accepted, 2nd Apr., 1898
Process for the Manufacture of Smokeless Powder.
I, BELA SCHRATZENTHALLER, Official of the I. & R. General Inspection of the
Austrian Railway, Eisengasse 25, Vienna, in the Empire of Austria, 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:
My invention consists essentially in the manufacture of a smokeless powder for
industrial and military purposes which I term "Unionite" and which can be
produced either in the form of scales or lamellæ or in the granulated form. This
smokeless powder gives rise to very little smoke, produces but a very slight recoil,
leaves very little residium; is absolutely free from danger; is unaffected by shocks,
blows or moisture; can be manufactured in a simpler manner and at a considerably
cheaper rate than other similar powders, while having a much greater ballistic effect,
so that 15 gr. of this powder yields the same results as 2.5 gr. of the Austrian
gunpowder No. 1. Moreover this powder retains its stability for a very long time and
is not liable to cause accidents and explosions owing to its becoming decomposed
through oxidation.
The manufacture of this powder is essentially the same whether it is made in the
form of scales or lamellæ or in the form of granules; there being a mere difference of
details.
The manufacture of this smokeless powder in the form of scales or lamellæ is as
follows:-
Thick filtering boards or sheets of paper made of cotton wool are placed in.
porcelain cups of corresponding size, when a mixture of 2 parts of red, fuming and
strong nitric acid at 48° and of 1 part of strong concentrated English sulphuric acid
at 66° (which mixture must be thoroughly cooled first) is poured over the same in
such a manner as to fill firstly the bottom part of the cup, placing one board or sheet
therein, then covering it over with a further quantity of liquid until it is thoroughly
soaked and then putting on another paper piece or board on the top. I may likewise
use 1 part of nitric acid of a specific gravity of 1.5 and 3 parts of sulphuric acid at 66°,
or 4 parts of nitric acid having a specific gravity of 1.50 and 10 parts of sulphuric
acid having a specific gravity of 1.84. The first time 5 sheets are nitrated
by 0.75 kg. of the acid mixture and are left at least 2 hours covered by the latter.
The boards are subsequently removed and are thoroughly washed preferably in running
water, but when running water is not obtainable, the pieces and the mixture are
placed in large water troughs arranged in a slightly inclined position and filled with
clean water entering at one end and running out at the other end at a somewhat
slow speed, the said troughs being occasionally shaken. The water must be renewed
several times and the pieces or boards must remain about two hours in the water.
After having been well washed, the said pieces or boards are immersed in a bath
containing a mixture, i.e. a solution of 5 parts of ammonia in 100 parts of water and
are allowed to remain in this aqueous bath for a period of from 3 to 4 hours. This
treatment which I term "fixing" has for its object to remove the last trace of acid
which may have still adhered to the boards or pieces. The latter are subsequently
washed in the manner above described in running water or in water otherwise kept

page_text: in motion wherein they are allowed to remain for a period of from 2 to 3 hours, after
which treatment they are suspended on lines or cords in an enclosed space well
supplied with air and heated to a temperature of 16° R. until they are thoroughly
well dried.
According to the degree of strength which is required for the powder, the treatment
above set forth is repeated 2, 3 or 4 times with this difference that 1.75 kg. of the
acid mixture will now be required for each 20 sheets. The sheets thus nitrated are
cut by any suitable cutting machine into small scales or lamellæ and the latter are
mixed or coloured with fine graphite powder in a suitable drum and are finally
cleaned by the aid of sieves after which the smokeless powder in scales or lamellæ is
ready for use.
The manufacture of the smokeless powder in a granulated form is carried on
substantially in the manner above described that is to say:
Instead of using, however, paper board, previously purified paper pulp is utilized.
This paper pulp must be made from cotton, and in order to dry it rapidly it is laid on
glass plates which are allowed to dry when the likewise dried paper pulp is scraped
off. This pulp is now ground into a fine powder (like flour) by means of a rolling
pin or of any suitable grinding machine and subsequently passed through one or
more sieves. The powder thus obtained is placed in a drum of porcelain, glass, clay,
or other suitable material which is capable of withstanding the action of acids; this
drum receiving a rotary motion from any suitable driving gear. The powder placed
in the drum is now covered with the same nitrating mixture of nitric acid and
sulphuric acid, such as was used in the manufacture of smokeless powder in the form
of scales or lamellae. The mixture must be previously cooled for a period of from 1
to 2 hours. The whole mixture is allowed to remain in the drum for about 3 or 4
hours, while the latter is constantly kept in rotation. When the drum is stopped
from time to time, the opening is occasionally uncovered in order to allow the vapours
to escape or provision may be made for such escape by fixing to the drum a suitable
appliance or device. Presently the acid mixture is allowed to run off, for which
purpose the drum is provided with an outlet which only allows a liquid to pass
through.
The paper pulp treated in this manner is removed from the drum by the aid of
glass shovels or scoops and is placed into another drum of glass or porcelain filled
with fresh water and likewise set in rotation. This drum is moved a few times to and
fro so that the powder may be thoroughly, washed, the water being allowed to run off
and fresh water being allowed to run in the drum from two to three times
consecutively, such treatment extending over a period of from 3 to 4 hours until the
powder has no more taste. The last water used having been allowed to run off, the
powder is removed by means of glass shovels or scoops and is introduced into a third
drum previously filled with a solution of 100 parts of fresh water and 5 parts of
ammonia in order to carry out the "fixing" process. The powder is left in this drum
for a period of from 2 to 3 hours, while the drum is being frequently rotated, when
it is brought back into the second drum which is filled with clean water in order to
wash such powder thoroughly again for a period of from 1 to 2 hours. The powder
is finally removed from this washing drum and is dried on plates of glass or porcelain.
After the drying operation, the powder is subjected 2, 3, or 4 times to the same
treatment according to the strength required for such powder. Finally the water is
allowed to run off, the pulp thus treated is removed and shaken first through fine
sieves and then on glass or porcelain plates, then it is granulated in a suitable
granulating apparatus, then polished and sorted. The powder in its final stage
has a white colour but may be coloured, if desired, by means of graphite.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
A process for the manufacture of smokeless powder in the form of scales or
granules characterized by the treatment of filter plates or boards of paner made

page_text: of cotton or of purified paper pulp with a thoroughly cooled mixture of 2 parts
of strong red and fuming nitric acid at 48° and one part of strong English
concentrated sulphuric acid at 48° or 1 part of nitric acid having a specific gravity
of 1.56 and 3 parts of sulphuric acid registering 66° or 4 parts of such nitric acid
and 10 parts of sulphuric acid, allowing nitrification to take place for several hours,
then subsequently washing the material thus treated and introducing the same in a
bath containing a solution of 5 parts of ammonia in 100 parts of water in order to
fix" the powder, which is subsequently washed again and subjected to a repetition
of the whole process several times according to the strength required for such powder,
the powder thus treated being finally dried.
"6
Dated this leth
1000
CRUIKSHANK & FAIRWEATHER,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow, Agents for the Applicant.