A NEW OR IMPROVED PROCESS FOR THE MANUFACTURE OF AMMONIA
Year: 1880

page_text: LETTERS PATENT to Hector Auguste Dufrené, of No. 10, Rue de la Fidélité,
Paris, and 4, South Street, Finsbury, London, Civil Engineer and Patent
Agent, for an Invention of "A NEW OR IMPROVED PROCESS FOR THE
MANUFACTURE OF AMMONIA." A communication from "la Société l'Azote," of
PROVISIONAL SPECIFICATION left by the said Hector Auguste Dufrené
at the Office of the Commissioners of Patents on the 29th December 1880.
HECTOR AUGUSTE DUFRENÉ, of No. 10, Rue de la Fidélité, Paris, and 4, South
Street, Finsbury, London, Civil Engineer and Patent Agent. "A NEW OR IMPROVED
PROCESS FOR THE MANUFACTURE OF AMMONIA." [A communication from "la Société
l'Azote," of No. 20, Rue Erard, Paris, in the Republic of France.]
The object of this Invention is the extraction of nitrogen from the air and the
manufacture of ammonia. For this purpose I combine nitrogen with hydrogen,
and the ammonia produced may be employed either alone or in combination with
a suitable acid for commercial or agricultural purposes to serve as a manure.
To ensure the combination of the nitrogen and hydrogen I utilize the action of
porous bodies either in a hot or a cold state.
Firstly. When heat is employed I take, by preference, oxide of iron, and specially
titanic oxide, and I reduce it so as to obtain very porous iron. On this iron,
which is kept at a red heat, is brought air, nitrogen, or hydrogen. With nitrogen
or air azotate of iron is formed, which I then decompose by causing a current of
hydrogen to pass over it, and ammonia is then formed and is collected. With
hydrogen the reduced iron is taken up, and a current of nitrogen being directed on
it ammonia is produced, with hydrogen thus combined or mixed with the iron.
Secondly. When cold is employed I take charcoal boiled in chloride of platinum,
then calcined to reduce the platinum, and I place it in a vessel into which I force
air, nitrogen, or hydrogen at a suitable pressure. The nitrogen or the hydrogen is
absorbed in the charcoal, causing hydrogen to pass when nitrogen has been
employed, or nitrogen if I have first caused hydrogen to pass. I again compress,
and by reason of the absorbing property of the charcoal and the presence of
platinum ammonia is formed.
To free it it is merely necessary to remove the pressure or to heat.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Hector Auguste Dufrené in the Great Seal Patent Office on the
28th June 1881.
HECTOR AUGUSTE DUFRENÉ, of 10, Rue de la Fidélité, Paris, and 4, South
Street, Finsbury, London, Civil Engineer and Patent Agent. "A NEW OR IMPROVED
PROCESS FOR THE MANUFACTURE OF AMMONIA." A communication from la Société
l'Azote, of 20, Rue Erard, Paris, in the Republic of France.
The object of this Invention is the extraction of nitrogen from the air and the
manufacture of ammonia. For this purpose I combine nitrogen with hydrogen,
and the ammonia produced may be employed either alone or in combination with
a suitable acid for commercial or agricultural purposes to serve as a manure.
To ensure the combination of the nitrogen and hydrogen I utilize the action of
porous bodies, either in a hot or a cold state, an electric current being employed if
necessary to facilitate the operation.
Firstly. When heat is employed I take by preference oxide of iron, and specially
titanic oxide, and I reduce it so as to obtain very porous iron. On this iron, which
is kept at a red heat, is brought air, nitrogen, or hydrogen. With nitrogen or air
a combination of iron and nitrogen is formed, which I then decompose by causing a
current of hydrogen to pass over it, and ammonia is then formed and is collected.
With hydrogen the reduced iron is taken up, and a current of nitrogen being
directed on it ammonia is produced, with hydrogen thus combined or mixed with
the iron.
Secondly. When cold is employed I take charcoal boiled in chloride of platinum,
then calcined to reduce the platinum, and I place it in a vessel into which I force
air, nitrogen, or hydrogen at a suitable pressure.
The nitrogen or the hydrogen is absorbed in the charcoal, causing hydrogen to
pass when nitrogen has been employed, or nitrogen if I have first caused hydrogen
to pass. I again compress, and by reason of the absorbing property of the charcoal
and the presence of platinum ammonia is formed.
To free it it is merely necessary to remove the pressure or to heat.
But to make the Invention better understood I will now proceed to describe the
same by reference to the accompanying Drawing, which shews a section of a suitable
construction of apparatus for carrying out the Invention.
This apparatus is constructed of a large furnace consisting of two crucibles A
and B, two heating chambers, M and N containing retorts r, r, r, r, r, r, and
8, 8, 8, 8, 8, 8, and deposit or sediment chambers O, O, P, P.
In the furnaces A and B, previously heated to red heat, I introduce melted zinc.
Air is conveyed into the furnace A through the passage a, and into the furnace B
steam is introduced through the passage b. On each side oxygen is fixed, and it
disengages itself at a very high temperature from the nitrogen and the hydrogen,
drawing along the oxide of zinc which is formed.
The hot gases at first heat the retorts r, r, r, r, r, r, and 8, 8, 8, 8, 8, 8, contained
in the furnaces M and N; they then run through the chambers O, O, P, P, where
the oxide is deposited; they then escape through the openings C, D, which conduct
them respectively into a chamber F, F, from which they may be drawn at will
through orifices e, f. From each of these orifices passes a conduct pipe, which
branches to each retort r, r, 1, 1, r, r, so that nitrogen or hydrogen may be brought
or conveyed at will into the retorts r, r, r, r, r', v.
These retorts contain iron in the form of sponge, and as much as possible
combined with titanium (fer titané), nitrogen is absorbed, hydrogen is then caused
to arrive, and ammonia is formed and escapes.

page_text: The oxide of zinc which is formed is collected in the hoppers n, n, n, n, n, n,
It is mixed with charcoal and then introduced into the inclined retorts 8, 8, 8, 8, to
effect its reduction so as to allow of its being again introduced into the furnaces A, B.
The oxide of carbon thus produced is burnt in such a manner as to form carbonic
acid, which may be united with ammonia for forming carbonate.
To facilitate the combination of iron and nitrogen I place in the retorts, in
mixture with the iron, a metal other than iron, and the thermo-electric currents
thereby produced will facilitate the operation.
Advantage may be taken of the porosity of the substances to employ pressure, in
which case the apparatus would have to be modified, and would be of much smaller
dimensions in order to obtain the desired resistance or strength. Hydrogen and
nitrogen are prepared under the same conditions, but the retorts are replaced by
cylindrical metal vessels capable of resisting a pressure of from ten to fifteen
atmospheres.
These vessels contain either carbon or pumice stone mixed with platinum, and
may be charged to ten atmospheres by means of a compression pump of any
suitable construction, and nitrogen will become liquified in the porous body. The
maximum pressure (which may be varied as may be desired) being attained, and
hydrogen being introduced by means of the same pump, the combination will take
place.
A cock being opened the ammonia will pass off in a gaseous state, and may then
combine as before with carbonic acid to form carbonate.
Having thus described the Invention communicated to me, and the best means
with which I am acquainted for carrying the same into effect, I would have it
understood that what is claimed and intended to be protected by the herein in part
recited Letters Patent is,
Firstly. The combustion of zinc, as herein described, so as to produce at one and
the same time heat and pure hydrogen and nitrogen.
Secondly. The condensation of these gases in porous substances, either from the
effect of heat or of pressure, and their subsequent combination by the same means
for forming ammonia, as herein before described.
In witness whereof, I, the said Hector Auguste Dufrené, have hereto set my
hand and seal, this Twenty seventh day of June, in the year of our Lord
One thousand eight hundred and eighty one.