IMPROVEMENTS IN THE MANUFACTURE OF SALTS OF AMMONIA, AND OTHER PRODUCTS FROM THE AMMONIACAL LIQUORS OF GAS WORKS AND ANIMAL CHARCOAL WORKS, AND IN THE STILL OR APPARATUS TO BE USER. IN SUCH MANUFACTURE
Year: 1862

page_text: LETTERS PATENT to John Ambrose Coffey, of 4, Providence Row,
Finsbury Square, and Theophilus Redwood, of 19, Montague Street,
Russell Square, both in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF SALTS OF AMMONIA, AND
OTHER PRODUCTS FROM THE AMMONIACAL LIQUORS OF GAS WORKS AND
ANIMAL CHARCOAL WORKS, AND IN THE STILL OR APPARATUS TO BE USER.
IN SUCH MANUFACTURE."
ealed the 16th January 1863, and dated the 27th August 1862.
PROVISIONAL SPECIFICATION left by the said John Ambrose Coffey and
Theophilus. Redwood at the Office of the Commissioners of Patents,.
with their Petition, on the 27th August 1862.
We, JOHN AMBROSE COFFEY, of 4, Providence Row, Finsbury Square.
and THEOPHILUS REDWOOD, of 19, Montague Street, Russell Square, both in
the County of Middlesex, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF SALTS OF AMMONIA AND OTHER
PRODUCTS FROM THE AMMONIACAL LIQUORS OF GAS WORKS AND ANIMAL CHARCOAL
WORKS, AND IN THE STILL OR APPARATUS TO BE USED IN SUCH MANUFACTURE," to be
as follows:-
The crude ammoniacal liquor is made to run through a still constructed
on the principal of the well known Coffey's still, such as is used for the distilla-
tion of spirits, but simpified in construction, such still being a series of shott
cylinders, boxes, or chambers, secured one upon the other with stop plates,
each to have an orifice at or near the centre with a flange to prevent the
liquor dropping through such orifice, until there is a lodgement. But alter
uate plates should each have curved openings, near the periphery or edge of the

page_text: same (with the exception of top and bottom of column) to allow the liquor to
pass (after forming another lodgement). In these boxes or chambers, say
one-third near the top, coils of pipes are placed, which pass through the central
orifice aforesaid, the ammoniacal liquor passes and discharges upon the plate,
say two-thirds from the bottom. Steam or hot air is admitted, and follows a
zig-zag direction to the ammoniacal liquor, carrying the gases with it. I can
combine and use together several of the series aforesaid; this arrangement
dispensing with the perforated plates, dropping pipes, valves, and such like
used in the ordinary Coffey's still aforesaid; the improved still being useful
for distillation generally.
But for the purpose of the manufacture of salts of ammonia and ammoniacal
liquors, the same should be made of iron or wood. After passing through the
still the gases and vapours which are separated in this process are conveyed
through vertical pipes or cylinders filled with coke, through which some acid,
such as sulphuric or muriatic acid, diluted with water, is allowed to run, for
the purpose of absorbing and combining with the ammonia; while sulphurated
hydrogen and cyanogen pass, and are absorbed in another part of the
apparatus, by bringing them into contact with a salt of iron, and with
precipitated or hydrated oxide of iron, either alone or mixed with sawdust
or other porous substance. The acid used for absorbing the ammonia may be
of such strength that it will form a concentrated solution while hot, from
which ammoniacal salt will be deposited as it cools. The oxide of iron, after
it has been used for absorbing the sulphurated hydrogen until it is saturated, is
to be exposed to the air, it will become re-oxidized, and the sulphur separated;
it may then be used again in the same way as before; when it has been thus
used for several times, the sulphur may be obtained from it by sublimation; or
it may be turned away from it, and converted into oil of vitriol. The liquor
which has run through the still may be afterwards treated with lime to
separate a further portion of ammonia from it.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed s
by the said John Ambrose Coffey and Theophilus Redwood in the
Great Seal Patent Office on the 27th February 1868.
TO ALL TO WHOM "THESE PRESENTS SHALL COME, we, JOHN
AMBROSE COFFEY, of 4, Providence Row, Finsbury Square, and THEOPHILUS
REDWOOD, of 19, Montague Street, Russell Square, both in the County of 3
Middlesex, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent bearing date the Twenty-seventh day of August, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-seventh year of Her
reign,did, for Herself, Her heirs and successors, give and grant unto us, the
said John Ambrose Coffey and Theophilus Redwood, Her special licence that
we, the said John Ambrose Coffey and Theophilus Redwood, our executors,
administrators, and assigns, or such others as we, the said John Ambrose Coffey
and Theophilus Redwood, our executors, administrators, and assigns, should
at any time agree with, and, no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "Im-
PROVEMENTS IN THE MANUFACTURE OF SALTS OF AMMONIA AND OTHER PRODUCTS
OP GAS WORKS AND ANIMAL CHARCOAL WORKS, AND IN THE STILL OR APPARATUS
TO BE USED IN SUCH MANUFACTURE; ALSO USEFUL FOR DISTILLERY IN GENERAL," upon
the condition (amongst others) that we, the said John Ambrose Coffey and
Theophilus Redwood, our executors or administrators, by an instrument
in writing under our, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed in
the Great Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that we, the said John Ambrose Coffey and Theophilus
Redwood, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The ammoniacal or other liquor to be operated upon is made to run through
a still constructed upon the principle of the well known Coffey's-still, such as
is used for the distillation of spirits, but simplified in construction. This still
consists of a series of short cylinders with intervening plates, or of a long
cylinder, with partitions or diaphragms therein. Each plate or diaphragm has
an orifice connecting one compartment or short cylinder with another, and' to
each orifice there is a flange to prevent the liquor from dropping through until
there is a lodgement. The orifices in alternate plates are at or near the
centres of the plates, and in the others they are at or near the edges or peri-
pheries. In the upper part of the still the ammoniacal or other liquor to be
operated upon is introduced through a coil of pipe, extending from the top
downwards through about one-third of the length of the column, as shown in
the Drawing Steam or hot air is admitted at the bottom, and ascends in a

page_text: tortuous course, passing over the surface of the liquor deposited on the plates,
and carrying the volatile matters with it. I prefer to have the cylinder circular
as shewn in the Drawing, on account of the greater strength it acquires from
that form, and from its being less liable to accident from explosion. This
still is well adapted for the distillation or rectification, not only of ammo-
niacal liquor, but also of alcohol, petroleum, and other liquids requiring such
treatment.
When this still is employed in the manufacture of salts of ammonia from
the ammoniacal liquor of gas works or animal charcoal works, the ammoniacal
liquor is made to enter the still at (A), and passing through the coil of pipes is
discharged at B on to the surface of one of the intersecting plates, while steam
from a steam boiler enters at (C), and passes upwards, thus coming into
contact with the ammoniacal liquor, and causing the separation from it in a
gaseous state of the ammonia and salts of ammonia present, and of other
gases and vapours; these gases and vapours pass out of the still through the
pipe (D, D), and are conveyed through a series of vertical tubes or cylinders
(E², E², E³, E, E³), which may be made of wood, lined inside with lead and
filled with pieces of coke and pumice stone, through which sulphuric or muri-
atic acid diluted with water is kept constantly running. If sulphuric acid be
used, it may be diluted to a suitable extent by mixing one part by measure of
common brown oil of vitriol, with from two to four parts by measure of water.
If muriatic acid be used, it may be diluted with an equal volume, or with half
its volume of water. The ammonia on coming into contact with the acid, is
absorbed and enters into combination, forming either sulphate or muriate of
ammonia, which passes in solution into the receivers F, G, H, which are
beneath the cylinders (E), When the acids are neutralized with ammonia,
they will form strong solutions, from which the ammoniacal salts may be
obtained in crystals either by the cooling or evaporation of the solutions; and
the evaporation may be economically effected by the intervention of a pan, as
shewn in the Drawing at I. (As it is important in conducting this process that
the whole of the ammonia should be absorbed as it passes through the
cylinders (E, and also that the acid should be neutralized with ammonia, the
acid should be made to run first through the cylinder E, and this acid, which
will not be neutralized on account of the small quantity of ammonia in that
cylinder, having been collected in the receiver (H) should be afterwards made
to run through the cylinders (E¹, E³, E³, E), where it will become fully
neutralized with ammonia.
The gases and vapours that are not condensed in the cylinder (E) are
afterwards conveyed through a pipe, as shewn in the Drawing, into the chamber

page_text: (K), where they are brought into contact with hydrated peroxide of iron,
either alone or mixed with sawdust or other porous substance. The hydrated
peroxide of iron, in a state suitable for use in this process, may be econonsically
prepared in the following way:-Dissolve one bundred and fifty pounds of
common green vitriol or sulphate of iron in a sufficient quantity of water to
effect its solution, add thereto fifty pounds of slaked lime, mix them together,
and when the oxide of iron has precipitated, mix it with about fifty pounds of
sawdust, and expose it to free contact with the air for several days. The
chamber (K) may be constructed in the same way as the "dry lime purifier"
of the gas works, and the mixture containing the oxide of iron is to be spread in
layers of about two or three inches in thickness upon the perforated shelves of
the chamber or box; the offensive gases which pass away from the cylinder (E,)
and which contain compounds of sulphur and cyanogen, on being brought
into contact with the oxide of iron in the chamber (K) will be absorbed,
so that the residuary gases that ultimately escape into the air will be free
from offensive odour. When the mixture used for this purpose has ceased to
produce the effect efficiently, it must be removed from the chamber (K), and
exposed to the air fór some days, by which means it will be rendered again
efficient, and fit for use as before. It may be thus used, and its efficiency
restored after use for ten or twelve times or more, but ultimately it will
become mixed with particles of sulphur, which will prevent its further
efficient action, and the sulphur may be then recovered from it by sub-
limating, or it may be burnt and converted into oil of vitriol in the usual way.
Having now described the nature of the said Invention, and in what
manner the same is to be performed, we hereby declare that we do not
intend to limit ourselves to.the use of the precise details herein-before set forth,
nor do we claim the same, except as constituent parts of the Invention herein-
before described.
In witness whereof, we, the said John Ambrose Coffey and Theophilus
Redwood, have hereunto set our hands and seals, the 27th day of
February, in the year of our Lord One thousand eight hundred and
JOHN A. COFFEY. (L.S.)
(L.S.)
T. REDWOOD.