from Ammonium Chloride.
Year: 1886

page_text: from Ammonium Chloride.
I LUDWIG MOND of Winnington Hall near Northwich, Cheshire, Manufacturing
Chemist, do hereby declare the nature of this invention to be as follows:-
If the vapour produced by volatilizing Ammonium Chloride is brought into
contact, at an elevated temperature, with protoxyde of nickel or with one of
numerous other metallic oxides, or a mixture or combination of them, the hydro-
chloric acid or chlorine combines with the oxide or its metal and the ammonia
passes off.
Also if the Chloride or oxychloride so formed is exposed at a suitable temperature
to the action of steam, preferably super-heated, it is again converted into oxide
and hydrochloric acid is given off.
I carry out my invention based on these facts in the following manner.
Ammonium chloride is volatilized by the application of heat and the vapour so
produced is passed over or through the protoxyde of nickel while heated to about
400° C.
The Ammonium Chloride may be mixed with the Protoxyde of Nickel before
heat is applied, but this is not necessary.
In either case the hydrochloric acid leaves the ammonia and is retained by the
oxide while the ammonia passes on, and is utilized or absorbed in any convenient
manner,
An inert gas (containing as little possible Oxygen, Hydrogen or steam) is now
passed through to drive out the remaining Ammonia, and then steam, preferably
superheated is passed over or through the material, heated to a suitable temperature.
The oxygen combines with the nickel forming an oxide, which can be used con-
tinually over again in this process, and the bydrochloric acid is given off, and can
be utilized in any desirable manner.
Besides the protoxyde of nickel the oxides of cobalt, manganese, zinc, iron,
alumina, copper, bismuth, magnesium, calcium and other metals can be advan-
tageously applied according to circumstances.
The temperature for the production of hydrochloric acid varies with the oxide
employed, and can easily be ascertained by any practical man.
To increase the active surface, and to obtain the material in a convenient form
for working this process, it is advantageous to impregnate pumice stone or other

page_text: porous inert material with the molten chloride or a solution of the chloride of the
metal to be employed, and after drying to heat the same in a current of steam or
air, so as to convert the chloride into oxide, or the oxide can be formed into lumps
of convenient size by agglomerating it with the help of a solution of the chloride
of the metal employed, or of any other salt and subsequently heating and drying
in a current of steam or air, or by mixing the oxide with inert agglomerating
substances and drying or otherwise.
Both operations can be carried on in a single retort or apparatus without
removal of the oxide, or the oxide can be treated with ammonium chloride in one
retort or apparatus and the treatment with steam be carried on in another.
Iron or clay retorts, preferably set vertically or obliquely are a convenient
apparatus for this purpose.

page_text: Improvements in Obtaining Ammonia and Hydrochloric Acid
from Ammonium Chloride.
I, LUDWIG MOND of Winnington Hall near Northwich Cheshire, Manufacturing
Chemist, 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 :-
If the vapour produced by volatilizing ammonium chloride is 'brought into
contact at an elevated temperature with protoxide of nickel or with one of
numerous other metallic oxides, or a mixture or combination of them, the hydro-
chloric acid or chlorine combines with the oxide or its metal, and the ammonia
passes off.
Also if the chloride or oxychloride so formed is exposed at a suitable temperature
to the action of steam, preferably superheated, it is again converted into oxide, and
hydrochloric acid is given off.
I carry out my invention based on these facts in the following manner:-
Ammonium chloride is volatilized by the application of heat and the vapour so
produced is passed over or through the protoxide of nickel while heated to about
400 degrees centigrade.
The exact temperature required differs, however, with different oxides.
The ammonium chloride may be mixed with the protoxide of nickel before heat
is applied, but this is not necessary. On the contrary, if the ammonium chloride
be separately volatilized and passed in the form of vapour over the oxide, the entire
cycle of operations can be repeatedly performed in the same chamber and without
disturbing the position of the oxide or chloride as the case may be-a decided
advantage.
Whichever way the chloride of ammonium be applied, the chlorine in the vapour
is retained by the oxide while the ammonia is set free and passes on and can be
utilized or absorbed in any convenient manner.
An inert gas such as producer gas, or the gas which leaves the absorbing
apparatus of the ammonia soda process containing as little oxygen, hydrogen or
steam as possible, is now passed through to drive out the remaining ammonia.
Steam, preferably superheated to about 450 degrees centigrade is now passed
over or through the material maintained at a suitable temperature, (in the case
where oxide of nickel is used about 400 degrees centigrade) The oxygen of the
steam combines with the nickel forming an oxide which can be used continually
over again in this process, the hydrogen combines with the chlorine, and the
hydrochloric acid is given off, which can be utilized in any desirable manner.
Besides the protoxide of nickel which I prefer to any other, the oxides of cobalt,
copper, zinc, magnesium, iron, manganese, aluminium, bismuth, and other heavy
metals possessing similar chemical properties to those named, or a mixture of these,
also as I have discovered since filing the provisional Specification, and protected
under another application, some of the combinations of one or more of these metals,
or of the alkali and alkaline earth metals with polybasic acids, such as silicic,
phosphoric, tungstic, boric, antimonic, or molybdic acids, (those only being available

page_text: which are not volatile and preferably not fusible at the temperatures employed)
can more or less advantageously be applied for this purpose.
The temperature for the production of hydrochloric acid varies with the oxide
employed and can easily be ascertained by any practical man.
To increase the active surface, and to obtain the material in a convenient forin
for working this process, it is advantageous to impregnate pumice stone or other
porous inert material with the molten chloride or a solution of the chloride of the
metal to be employed, and after drying to heat the same in a current of steam or
air, so as to convert the chloride into oxide, or the oxide can be formed into lumps
of convenient size by agglomerating it with the help of a solution of the chloride
of the metal employed, or a solution of sugar, gum, or similar substance, and
subsequently drying and heating in a current of steam or air, or by mixing the
oxide with inert agglomerating substances, and drying or otherwise.
Both operations can be carried on in one and the same retort or apparatus
without removal of the oxide, or the oxide can be treated with ammonium chloride
in one retort or apparatus, and the treatment with steain be carried on in another.
A convenient apparatus for carrying out this invention consists of cast iron
retorts lined inside with thin earthenware tiles. A number of these retorts may
be conveniently set in one common furnace heated by direct fire or preferably by
generator gas. I prefer to put the retorts obliquely into the furnace at an angle
of about 30 degrees. The retorts pass through the walls of the furnace at both
sides, and are at both ends provided with covers and also with openings for the
inlet and outlet of gases, which latter are by means of pipes and taps or valves
connected to the sources of the gases to be employed, and to the apparatus used for
absorbing or otherwise utilising the gases produced.
These retorts are filled to about one half with balls or lumps of protoxide of
nickel or other active material prepared as bereinbefore described, the upper part
of the retort remaining empty.
In commencing the operation the retorts and contents are heated to about
400 degrees centigrade, and the empty part of the retorts is then filled with solid
ammonium chloride and the cover immediately put on. The temperature is
maintained at about 400 degrees centigrade, until all the ammonium chloride is
volatilized, and the ammonia issuing from the lower end of the retort is conducted
to a convenient apparatus for absorbing it in a solution of chloride of sodium, or
otherwise.
An inert gas such as is herein before described is now passed through the retort
to expel the ammoniacal gas remaining in it, and this is also let into the absorbing
apparatus. A slow current of steam, preferably heated in an ordinary superheating
apparatus to about 400 degrees centigrade, is now passed through the retorts which
are as nearly as possible kept at the same temperature. Previously to admitting
the steam the valves in the conduits leading from the retorts to the ammonia
absorbing plant are shut, and another set of valves opened which lead to the
apparatus in which the hydrochloric acid is to be utilized. If the current of steam
is carefully regulated, nearly pure hydrochloric acid is obtained which is condeused
or otherwise utilized by any ordinary well known method.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1st. The process of obtaining ammonia and hydrochloric acid from solid ammonium
chloride, which consists in vaporising the ammonium chloride, passing the vapour at
an elevated temperature over or through protoxide of nickel or one or several of
the oxides of cobalt, magnesium, zinc, copper, iron, manganese, aluminium, and
other heavy metals possessing similar chemical properties to those named, loosely
piled in a closed chamber or retort made of or lined with materials refractory
to the chemicals employed, collecting the ammonia thereby separated, passing
a neutral gas (such as described) through the chamber or retort to drive out the

page_text: residual ammonia, then passing through the chamber or retort still containing the
solid materials previously acted on, and maintained at a suitable temperature,
steam preferably superheated, whereby hydrochloric acid is obtained, which can be
utilized in any known manner.
2nd. The process of obtaining ammonia and hydrochloric acid from ammonium
chloride, which consists in bringing the vapour of the ammonium chloride in
contact with protoxide of nickel or one or several of the oxides of cobalt,
magnesium, zinc, copper, iron, manganese, aluminium, bismuth, or other heavy
metals possessing similar chemical properties to those named at an elevated
temperature till the oxide is sufficiently chloridised, and then passing in steam
at a suitable temperature to obtain hydrochloric acid.
3rd. The improvement in the process of obtaining ammonia from ammonium
chloride, which consists in passing the vapour of ammonium chloride at an elevated
temperature over or through the herein before mentioned residual oxides from the
previous operation so as to obtain ammonia.
4th. The improvement in the process of obtaining ammonia from ammonium
chloride, which consists in forming protoxide of nickel or one or several of the
oxides of cobalt, magnesium, zinc, copper, iron, manganese, aluminium, bismuth or
other heavy metals possessing similar chemical properties to those named, into
bricks or lumps, or balls, loosely piling them in a chamber and bringing them in
contact with the ammonium chloride at an elevated temperature such as described.
5th. The process of obtaining ammonia and hydrochloric acid successively from
ammonium chloride, which consists in passing successively vapour of ammonium
chloride, a neutral gas, and steam superheated through one and the same retort or
chamber containing protoxide of nickel, or one or several of the oxides of cobalt,
magnesium, zinc, copper, iron, manganese, aluminium, bismuth, or other heavy
metals possessing similar chemical properties to those named, loosely piled, and
repeating the process continuously so as to use the same solid materials con-
tinuously, without handling or moving them in any way.
6th. The improvement in the process of obtaining aminonia and hydrochloric
acid successively from ammonium chloride through a vessel or chamber containing
protoxide of nickel, or one or several of the oxides of cobalt, magnesium, zinc,
copper, iron, manganese, aluminium, bisinuth, or other heavy metals possessing
similar chemical properties to those named and then driving out the residual
ammonia by means of a neutral gas, and collecting the same before blowing in
steam whereby all the ammonia is saved instead of being partially wasted as it
would be if the steam were admitted instead of the neutral gas.
7th. The improvement in obtaining hydrochloric acid from the ammonium
chloride by means of protoxide of nickel, or one or several of the oxides of cobalt,
magnesium, zinc, copper, iron, manganese, aluminium, bismuth or other heavy
metals possessing similar chemical properties to those named, which consists in
treating the chlorides or oxychlorides formed by the action of the vapour of
ammonium chloride or the oxides named, with steam previously heated to an
elevated temperature so as to reduce as much as possible the supply of heat through
the walls of the apparatus employed.