IMPROVEMENTS IN THE MANUFACTURE OF NITRO-GLYCERINE
Year: 1878

page_text: LETTERS PATENT to Thomas Tolley Jones, of Basinghall Street, in the City of
London, Merchant, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE
OF NITRO-GLYCERINE." A communication from abroad by Frederick Mann, of
Koroit Creek, Victoria, Australia, Manufacturing Chemist.
Sealed the 19th March 1878, and dated the 23rd January 1878.
PROVISIONAL SPECIFICATION left by the said Thomas Tolley Jones at the
Office of the Commissioners of Patents on the 23rd January 1878.
THOMAS TOLLEY JONES, of Basinghall Street, in the City of London, Merchant.
"IMPROVEMENTS IN THE MANUFACTURE OF NITRO-GLYCERINE." [A communication
from abroad by Frederick Mann, of Koroit Creek, Victoria, Australia, Manufacturing
Chemist.]
It is well known that nitro-glycerine is manufactured by the admixture of
glycerine with nitric and sulphuric acids, and the subsequent washing away of the
waste acids in very cold water. This water is made very cold because of the strong
tendency of the nitro-glycerine to decompose except when kept at a very low
temperature. Notwithstanding the coldness of the water, however, there is a
considerable heat engendered immediately the acids mix with the water. This
heat injuriously affects the nitro-glycerine which accompanies the acids, causing its
partial decomposition and lowering its quality.
This Invention has been designed for the express purposes of preventing this
decomposition and lowering of the quality of the nitro-glycerine; and of recovering
the waste acids, which by the processes at present in use are irrecoverably lost. It
consists in first crystallizing the nitro-glycerine by freezing before attempting to
separate it from the acids, and then separating such crystals from such acids by a
centrifugal washer, such as is used for the separation of sugar crystals from molasses,
or by any other of the machines now in use for separating a crystal from a liquid.
A subsidiary portion of the said Invention consists in the subsequent treatment of
such waste acids when recovered, so as to bring them into a marketable form.

page_text: In making nitro-glycerine according to this Invention the acids and glycerine
may be mixed in any of the methods commonly employed. When this has been
done this Invention comes into play, for instead of conducting such mixture into a
large quantity of very cold water I subject it at once to a sufficiently low tempera-
ture to freeze or crystallize the nitro-glycerine contained therein. This is not
readily accomplished, but it is very greatly assisted if a very small portion, say a
tea-spoonful, of previously frozen nitro-glycerine be thrown into the vessel
containing the mixture. This addition of frozen nitro-glycerine is not necessary
except when making the first charge, inasmuch as sufficient frozen material clings
to and remains on the sides of the vessel after the first charge. The fact of its
having frozen is known by a very sudden rise in the temperature of the mixture,
which rise is indicated on a thermometer attached thereto; this rise will amount to
several degrees, say from 15° to 25°; and is seen at a glance. When this has been
accomplished I separate the crystallized nitro-glycerine from the waste acids by
placing the whole in a centrifugal machine, such as is commonly used for separating
crystallized sugar from molasses. The crystallized nitro-glycerine thus obtained I
then place in cold water, when it liquefies and sinks to the bottom, from whence it
can be drawn and used for any. purpose.
The waste acids removed by the centrifugal separation contain certain organic
compounds, which it is desirable, if not necessary, to remove before using for any
other purpose except the reproduction of sulphuric acid. To this end I conduct
such acids into a suitable still, such as is well known to manufacturing chemists,
and there subject them to the action of superheated steam until the organic
compounds therein begin to decompose, which is known by the presence of red
fumes arising. As soon as these appear I substitute heated air for the steam, so as
to complete such decomposition without further reducing the specific gravity of the
acids. This I continue until the red fumes cease. then cut off the supply of
heated air, and allow the mixture to cool, when it can be used for most of the
purposes to which common sulphuric acid is applied.
Instead of subjecting such waste acids to this purifying process, they may be
used directly in the further manufacture of sulphuric acid when the organic nitro
compounds therein would be utilized.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Tolley Jones in the Great Seal Patent Office on the 20th
July 1878.
THOMAS TOLLEY JONES, of Basinghall Street, in the City of London, Merchant.
"IMPROVEMENTS IN THE MANUFACTURE OF NITRO-GLYCERINE." A communication
from abroad by Frederick Mann, of Koroit Creek, Victoria, Australia, Manufacturing
Chemist.
It is well known that nitro-glycerine is manufactured by the admixture of
glycerine with nitric and sulphuric acids, and the subsequent washing away of the
waste acids in very cold water. This water is made very cold because of the strong
tendency of the nitro-glycerine to decompose except when kept at a very low
temperature. Notwithstanding the coldness of the water, however, there is a
considerable heat engendered immediately the acids mix with the water. This
heat injuriously affects the nitro-glycerine which accompanies the acids, causing its
partial decomposition and lowering its quality.
This Invention is designed for preventing this decomposition and lowering of the
quality of the nitro-glycerine, and for recovering the waste acids, which by the
processes at present in use are irrecoverably lost. It consists in first crystallizing
the nitro-glycerine by freezing before attempting to separate it from the acids, and
then separating such crystals from the acids by a centrifugal washer similar to
those used for the separation of sugar crystals from molasses, or by any other of
the machines now in use for separating a crystal from a liquid. A subsidiary
portion of the said Invention consists in the subsequent treatment of such waste
acids when recovered as to bring them into a markėtable form.
In making nitro-glycerine according to this Invention the acids and glycerine
may be mixed in any of the methods commonly employed. When this mixture has
been effected my Invention comes into operation, for instead of conducting such
mixture into a large quantity of very cold water I subject it at once to a sufficiently
low temperature to freeze or crystallize the nitro-glycerine contained therein. This
object is not readily accomplished, but it is very greatly assisted if a very small
portion, say a tea-spoonful, of previously frozen nitro-glycerine is thrown into the
vessel containing the mixture. This addition of frozen nitro-glycerine is not
necessary except when making the first charge, inasmuch as sufficient frozen
material clings to and remains on the sides of the vessel after the first charge. The
fact of its having frozen is indicated by a very sudden rise in the temperature of
the mixture, which rise is shewn on a thermometer attached thereto; this rise will
amount to several degrees, say from 15° to 25°, and is seen at a glance. When this
has been accomplished I separate the crystallized nitro-glycerine from the waste
acids by placing the whole in a centrifugal machine, such as those commonly used
for separating crystallized sugar from molasses. The crystallized nitro-glycerine
thus obtained I then place in cold water, when it liquefies and sinks to the bottom,
whence it can be drawn and used for any purpose.
The waste acids removed by the centrifugal separator contain certain organic
compounds, which it is desirable, if not necessary, to remove before using them for
any other purpose except the reproduction of sulphuric acid. To this end I conduct
such acids into a suitable still, such as is well known to manufacturing chemists,
and there subject them to the action of superheated steam until the organic
compounds therein begin to decompose, their decomposition being shewn by the
presence of red fumes. As soon as these appear I substitute. heated air for the
steam to complete such decomposition without further reducing, the specific gravity
of the acids. This I continue until the red fumes cease. I then cut off the supply
of heated air and allow the mixture to cool, when it can be used for most of the
purposes to which common sulphuric acid is applied.
Instead of subjecting such waste acids to this purifying process they may be

page_text: used directly in the further manufacture of sulphuric acid when the organic nitro
compounds therein would be utilized.
Having thus fully described the said Invention, and the manner of performing"
the same, I wish it understood that I claim,―
In the process of manufacturing nitro-glycerine, crystallizing the nitro-glycerine
by freezing it before separating it from the acids in which it has been made, and
subsequently separating such crystallized nitro-glycerine from the waste acids (by
preference in a centrifugal washer), as above set forth.
Also the subsequent treatment of the waste acids, as above set forth.
In witness whereof, I, the said Thomas Tolley Jones, have hereunto set my
hand and seal, this Seventeenth day of July, in the year of our Lord
One thousand eight hundred and seventy-eight.
MATTHY