IMPROVEMENTS IN THE MANUFACTURE OF AMMONIA
Year: 1881

page_text: LETTERS PATENT to Charles Denton Abel, of No. 28, Southampton
Buildings, Chancery Lane, in the County of Middlesex, for an Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF AMMONIA." A communica-
tion from abroad by Frederick Twinch, of No. 67, Rue Truffaut, Paris,
France.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at the
Office of the Commissioners of Patents on the 25th August 1881.
CHARLES DENTON ABEL, of No. 28, Southampton Buildings, Chancery Lane, in
the County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF AMMONIA."
[A communication from abroad by Frederick Twinch, of No. 67, Rue Truffaut,
Paris, France.]
It is well known that hydrogen in the nascent state is capable of combining
directly with nitrogen when obtained likewise in the nascent state, and that the two
elementary substances on combining form the compound substance known as
" ammonia."
According to the present Invention this property of hydrogen and nitrogen is
made use of to produce ammonia by a continuous manufacturing process, by com-
bining several well known chemical reactions, and by making use in addition to
these reactions of a chemical change which hitherto has not been employed for such
purpose, and which is analogous to that successfully practised in the manufacture
of oil of vitriol by the so called chamber-process, viz., of the change which nitrogen
dioxide undergoes in the presence of oxygen or air, and whereby it is converted
into the higher oxides of nitrogen which serve in their turn as oxidizing agents on
account of the great facility with which they part again with their oxygen, and
are reduced once more to the state of nitrogen dioxide, and under favourable
conditions even to nitrogen nonoxide or to nitrogen.
This remarkable property of the nitrogen oxides, which has gained for them the
title of "carriers of oxygen" in the manufacture of oil of vitriol, has been found to
be be equally available for the manufacture of ammonia. The lower nitrogen

page_text: oxide or oxides, when brought in contact with atmospheric air, immediately deprive
the air of its oxygen, and set free the nitrogen, which latter gas when thus liberated
from air may be said to be in the nascent state, and possesses the chemical properties
which it does not possess otherwise. It is capable in fact of combining directly
with hydrogen, which must however be presented to it, also in the nascent state,
forming with it the compound body " ammonia."
In order to obtain hydrogen in the nascent state the well known action is utilised
which certain metals, especially the metal zinc, exert upon water (steam), or upon
the so-called fixed alkaline hydrates, whereby hydrogen gas is liberated and oxide
of zinc is formed, which latter remains dissolved in the caustic alkali, a slow
current of the alkali being made to pass continuously over the metal. The decom-
position is effected by passing steam over the metal, which should be obtained in
such a state as to present the largest possible surface to the action of the steam and
alkali, such as in the form of borings, shavings, or in what is known by chemists
as the granulated state. The metal previously to being charged into the vessel in
which the decomposition is effected, may with advantage be coated with a thin film
of galvanically deposited copper. The vessel which has been found suitable for.
this purpose consists of an iron cylinder placed in an upright position and sur-
rounded by an outer iron casing, through which steam superheated or not is made
to circulate freely. The inner cylinder is charged with zinc alone, or with the so-
called zinc copper couple, in such a manner as to leave sufficient space and no more
for the passage of the liquid and gaseous bodies which have to be introduced. The
upper end is provided with an inlet pipe for the passage of steain and air, another
inlet pipe for the passage of nitrogen dioxide or other suitable oxide of nitrogen to
be generated by processes which are well understood, and a third inlet for the
introduction of the caustic alkali, by preference of a solution of sodic hydrate,
which should be distributed equally all over the metallic body or bodies. The
lower end of the inner cylinder is provided with taps and outlets suitable for
drawing off the alkaline liquid, holding in solution the zinc oxide which is formed
in the chemical reaction, as well as for collecting the ammoniacal liquor or gaseous
ammonia; this latter can be readily absorbed either in water or in dilute acids by
means of suitable condensing vessels similar in form to those employed by manu-
facturers for the condensation of gaseous acids.
By the proper regulation of the admission of the steam and air, as well as of
the sodic hydrate and nitrogen oxides to the inner cylinder, little gaseous non-
condensible matter will be found to escape. The steam or sodic hydrate yields its
oxygen to the zinc and its bydrogen to the nitrogen which is liberated from the air,
the oxygen of the latter being likewise taken up by the zinc either directly or
indirectly through the agency of the nitrogen oxide or oxides. The quantity of
the latter should be regulated so as to be sufficient and no more to effect the
deoxidation of the air and the transferment of the atmospheric oxygen to the
metallic zinc under the influence of heat, steam, and caustic alkali. Any larger
quantity would furnish likewise nascent nitrogen, but the production of nitrogen
from this source would not be as economical as that from atmospheric air, the
latter being a gaseous mixture proportionally far richer in nitrogen, the constituent
necessary for the production of ammonia. It has been found in practice that the
chemical action which takes place inside the cylinder can be regulated by ascer-
taining by the usual chemical tests whether any free bydrogen or undecomposed air
or nitrogen oxides issue from the cylinder, these being noncondensible gaseous
bodies.
The bye-products of this process, viz., zinc oxide, which is held in solution by
the caustic alkali, can be recovered again from the alkaline solution, and utilised
by processes well understood by chemists. The recovered alkali may be used over
again in the above described process.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Denton Abel in the Great Seal Patent Office on the
24th February 1882.
CHARLES DENTON ABEL, of No. 28, Southampton Buildings, Chancery Lane; in
the County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF AMMONIA.”
A communication from abroad by Frederich Twinch, of No. 67, Rue Truffaut,
Paris, France.
It is well known that hydrogen in the nascent state is capable of combining
directly with nitrogen when obtained likewise in the nascent state, and that the
two elementary substances on combining form the compound substance known as
ammonia.
According to the present Invention this property of hydrogen and nitrogen is
made use of to produce ammonia by a continuous manufacturing process, by
combining several well known chemical reactions, and by making use in addition
to these reactions of a chemical change which hitherto has not been employed for
such purpose, and which is analogous to that successfully practised in the manu-
facture of oil of vitriol by the so called chamber-process, viz., of the change which
nitrogen dioxide undergoes in the presence of oxygen or air, and whereby it is
converted into the higher oxides of nitrogen, which serve in their turn as oxidizing
agents, on account of the great facility with which they part again with their
oxygen, and are reduced once more to the state of nitrogen dioxide, and under
favourable conditions even to nitrogen nonoxide or to nitrogen.
This remarkable property of the nitrogen oxides, which has gained for them the
title of "carriers of oxygen" in the manufacture of oil of vitriol, has been found to
be equally available for the manufacture of ammonia. The lower nitrogen oxide or
oxides when brought in contact with atmospheric air immediately deprive the air
of its oxygen, and set free the nitrogen, which latter gas when thus liberated from
air may be said to be in the nascent state, and possesses the chemical properties
which it does not possess otherwise. It is capable in fact of combining directly
with hydrogen, which must however be presented to it also in the nascent state,
forming with it the compound body "ammonia."
In order to obtain bydrogen in the nascent state the well known action is
utilised which certain metals, especially the metal zinc, exert upon water (steam),
or upon the so called fixed alkaline hydrates, whereby hydrogen gas is liberated,
and oxide of zinc is formed, which latter remains dissolved in the caustic alkali,
a slow current of the alkali being made to pass continuously over the metal. The
decomposition is effected by passing steam over the metal, which should be obtained
in such a state as to present the largest possible surface to the action of the steam
and alkali, such as in the form of borings, shavings, or in what is known by
chemists as the granulated state. The metal previously to being charged into the
vessel in which the decomposition is effected may with advantage be coated with a
thin film of galvanically deposited copper. It will be evident that variously
arranged apparatus may be employed for carrying out the above described process;
an arrangement which has been found suitable for this purpose consists of an iron
cylinder placed in an upright position, and surrounded by an outer iron casing
through which steam, superheated or not, is made to circulate freely. The inner
cylinder is charged with zinc alone, or with the so-called zinc-copper couple, in
such a manner as to leave sufficient space and no more for the passage of the
liquid and gaseous bodies which have to be introduced; the upper end is provided
with an inlet pipe for the passage of steam and air, another inlet pipe for the
passage of nitrogen dioxide or other suitable oxide of nitrogen, to be generated by

page_text: processes which are well understood, and a third inlet for the introduction
of the caustic alkali, by preference, a solution of sodic hydrate, which should be
distributed equally all over the metallic body or bodies. The lower end of the
inner cylinder is provided with taps and outlets suitable for drawing off the
alkaline liquid holding in solution the zinc oxide, which is formed in the chemical
reaction; as well as for collecting the ammoniacal liquor or gaseous.ammonia; this
'latter can be readily absorbed either in water or in dilute àcids by means of
suitable condensing vessels, similar in form to those employed by manufacturers
for the condensation of gaseous acids.
•
By the proper regulation of the admission of the steam and air, as well as of
the sodic hydrate and nitrogen oxides to the inner cylinder, little gaseous non-
condensible matter will be found to escape. The steam or sodic hydrate yields
its oxygen to the zinc, and its hydrogen to the nitrogen, which is liberated from
the air; the oxygen of the latter being likewise taken up by the zinc, either
directly or indirectly through the agency of the nitrogen oxide or oxides. The
quantity of the latter should be regulated so as to be sufficient and no more to
effect the deoxidation of the air, and the transferment of the atmospheric oxygen
to the metallic zinc under the influence of heat; steam, and caustic alkali. Any
larger quantity would furnish likewise nascent nitrogen, but, the production of
nitrogen from this source would not be as economical as that from atmospheric
air, the latter being a gaseous mixture proportionally far richer in nitrogen, the
It has been found in
constituent necessary for the production of ammonia.
practice that the chemical action, which takes place inside the cylinder, can be
regulated by ascertaining by the usual chemical tests whether any free hydrogen
or undécomposed air or nitrogen oxides issue from the cylinder, these being non
condensible gaseous bodies.
The bye-products of this process, viz., zinc oxide, which is held in solution by
the caustic alkali, can be recovered again from the alkaline solution, and utilised by
processes well understood by chemists. The recovered alkali may be used over
again in the above described process.
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, as communicated to me by my foreign correspondent,
I claim,-
The manufacture of ammonia by causing nitrogen liberated from atmospheric air
by the action thereon of the lower nitrogen oxides to combine at the moment of
its liberation with nascent hydrogen liberated from aqueous vapour or alkaline
hydrates, or from both by the action of metals thereon in the presence of heat,
substantially as herein described.
.
In witness whereof, I, the said Charles Denton Abel, have hereunto set my
hand and seal, this Twenty fourth day of February, in the year of our Lord
One thousand eight hundred and eighty two.