AN IMPROVED PROCESS OF AND APPARATUS FOR MANUFACTURING SULPHOCYANIDES AND FERROCYANIDES
Year: 1878

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents, 66,
Chancery Lane, in the County of Middlesex, Civil Engineer, for the Invention
of "AN IMPROVED PROCESS OF AND APPARATUS FOR MANUFACTURING
SULPHOCYANIDES AND FERROCYANIDES." A communication from abroad by
Joseph Tcherniac and Ury Gunzburg, both of Paris, in the Republic of
France.
Sealed the 10th September 1878, and dated the 22nd March 1878.
PROVISIONAL SPECIFICATION left by the said William Edward Newton at
the Office of the Commissioners of Patents on the 22nd March 1878.
WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer. 'AN IMPROVED PROCESS OF AND APPARATUS
FOR MANUFACTURING SULPHOCYANIDES AND FERROCYANIDES." [A communication
from abroad by Joseph Tcherniac and Ury Gunzburg, both of Paris, in the Republic
of France.]
The process which forms the subject of the present Invention is founded upon the
use of sulphide of carbon and of ammonia. It requires special apparatus which will
be hereafter described, but the Inventors do not intend to confine themselves rigidly
to a particular construction of parts, as the form and arrangement may be varied
within certain limits, as may be found desirable in practice.
In carrying out the Invention for the production of sulphocyanides and ferro-
cyanides, a close wrought-iron vessel or boiler something like a Papin's digester is
required. This vessel or digester is lined with enamel, and is capable of resisting
strong pressure, and into it is introduced through a tube extending from the top
cover to the lower part of the digester 100 parts of sulphide of carbon, and 200
parts of a solution of ammonia. The digester is provided with an agitator or stirrer,
whereby the liquids may be intimately mixed, but this mechanical stirring may be
avoided if the lower part of the vessel is heated by steam or otherwise to about 110°
cent., while the upper part is kept cool by means of a stream of water.

page_text: By this means a continuous distillation of the most volatile liquid (the sulphide
of carbon) is effected from the hotter parts of the apparatus towards the colder
parts, and the perfect mixture of the ingredients will thus be effected automatically.
At the end of 3 or 4 hours of heating, the operation will be completed, and there
will be found a sulphocyanide of ammonium and sulphuretted hydrogen, according
to the following equation,-
CS+2NH_HS+NGSNH
=
The tube which passes through the cover of the digester and extends downwards
to the bottom, is provided with a cock, and when the operation is finished this cock
is opened, and the pressure which exists inside the digester forces the liquid up the
pipe and through a refrigerator or condenser into another vessel which admits of
that portion of the sulphide of carbon which has not been acted upon being removed.
From thence the liquid is run into a double-bottomed cast-iron vessel heated by
steam at 125° cent.
The evaporation is stopped when the temperature of the liquid reaches 120° cent.
The solution of sulphocyanide of ammonium with the addition of the necessary
quantity of quicklime is introduced into an apparatus for the purpose of taking up
the ammonia contained in the sulphocyanide of ammonium, and which represents
half of the total quantity of ammonia employed in the process; the sulphocyanide
of ammonium is thus transformed into the sulphocyanide of lime.
The apparatus required for this purpose is composed of two close vessels or
boilers A and B, one placed above the level of the other, and heated by the same
fire-place, and each is provided with a stirrer or agitator.
The two vessels are half filled with the mixture of sulphocyanide of ammonium
and of lime, and when the lower boiler A is heated, the gas or vapour evolved will
pass through a coil of tube plunged into the liquid of the second vessel B.
The steam which is carried over with the gases will heat the contents of the
vessel B, and the gas which will be thereby disengaged will be carried by a pipe to
the first vessel A, and will become mixed with the ammonia contained in this vessel.
The ammoniacal gas is conducted alternately to two sheet-iron pans which
contain the ordinary ammonia of commerce, and are provided with refrigerating
apparatus.
'
.
A graduated liquid gauge admits of the progress of the saturation being watched,
and by this means the concentrated ammonia necessary for the success of the
process is obtained.
This apparatus may be employed for the manufacture of solution of ammonia from
ammoniacal salts.
When the thermometer, which is plunged in the liquid in the lower vessel A
inarks 115° cent., the vessel is emptied by opening the cock on the drawing-off tube.
It is then filled again with the liquid contained in the upper vessel B, and this
latter is then charged with fresh liquid. By this means the operation is made
continuous, and admits of nearly the whole of the ammonia being extracted from
the solution.
It is scarcely necessary to say that when it is desired to prepare the sulphocyanide
of ammonium itself for sale, it will only be necessary to leave the liquid that has
been evaporated at 125° cent. to crystallize when a perfectly pure salt in the form
of crystals will be obtained.
The sulphocyanide of lime serves as a medium in the manufacture of other sulpho-
cyanides.
It will only be necessary in fact to add a carbonate or some soluble sulphate to
obtain at once a deposit or precipitate of sulphate or carbonate of lime, and a
solution of the new sulphocyanide. Thus, for instance, in order to prepare a
sulphocyanide of potassium, a concentrated solution of sulphate of potash filtered
and evaporated may be added to the solution of sulphocyanide of lime.
The following is the process now adopted for converting the sulphocyanide of
potassium, and sulphocyanides in general into ferrocyanides :-An intimate mixture
is made of 6 equivalents of sulphocyanide of potassium in a perfectly dry state with

page_text: 5 equivalents of lime, 5 equivalents of carbon, and one equivalent of iron in
a finely divided state obtained by reducing by means of carbon the residue of
pyrites, a good quality in an apparatus in which the iron may be reduced without
coming in contact with the air. This mixture of materials is heated to redness,
and the following re-action takes place :-
6KŠON+6 CaO+5C+Fe=FeS+5CaS+5 CO+6KGN.
It will only be necessary to treat the mass when cooled by water at the ordinary
temperature, in order to obtain a solution of ferrocyanide of potassium which will
be formed according to the following equation:-
FeS+6 KON KS+KFеCNº.
The solution obtained is concentrated and left to crystallize, when it will furnish
fine crystals of ferrocyanide of potassium in abundance.
The apparatus for obtaining the iron in a finely divided state from the residue of
pyrites consists of a cylinder, the sides of which are heated by a suitable fire-place.
The bottom of the cylinder is movable, and, being mounted on a hinge, is capable of
being drawn back by means of a sector rack and pinion, so as to let the contents of
the cylinder drop into a hopper and be conducted from thence to a close vessel
mounted on wheels, so that the pyrites may be withdrawn from the cylinder,
removed away, and allowed to cool without being brought in contact with the air.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Edward Newton in the Great Seal Patent Office on the
19th September 1878.
WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer. "AN IMPROVED PROCESS OF AND APPARATUS
FOR MANUFACTURING SULPHOCYANIDES AND FERROCYANIDES." A communication
from abroad by Joseph Tcherniac and Ury Gunzburg, both of Paris, in the Republic
of France.
The process which forms the subject of the present Invention is founded upon
the use of sulphide of carbon and of ammonia. It requires special apparatus which
will be hereafter described, but the Inventors do not intend to confine themselves
rigidly to the peculiar construction of parts herein-after set forth, as the form and
arrangement of the apparatus may be varied within certain limits, as may be found
desirable in practice.
In carrying out the Invention for the production of sulphocyanides and ferro-
cyanides, the apparatus shewn in the accompanying Drawing is employed.
Fig. 1 is a vertical section of one form of apparatus, and Fig. 1a is a plan view of
the same.
It consists of a close wrought-iron vessel or boiler A, something like a
Papin's digester. This vessel or digester A is lined with enamel, and is capable of
resisting strong pressure. Into this vessel A through a tube E (extending from the
top cover to the lower part of the digester), one hundred parts of sulphide of carbon
and two hundred parts of a solution of ammonia are introduced. The vessel A is

page_text: provided with an agitator or stirrer D, whereby the liquids may be intimately
mixed, but this mechanical stirring may be avoided if the lower part of the vessel
be heated by steam or otherwise to about one hundred and ten degrees cent., while
the upper part is kept cool by means of a stream of water.
By this means a continuous distillation of the most volatile liquid (the sulphide
of carbon) is effected from the hotter parts of the apparatus towards the colder
parts, and the perfect mixture of the ingredients will thus be effected automatically.
At the end of three or four hours of heating the operation will be completed, and
there will be formed a sulphocyanide of ammonium and sulphuretted hydrogen,
according to the following equation:
CS+2 NH³=H'S+NCSNH*.
The tube E which passes through the cover of the vessel A, and extends down-
wards to the bottom, is provided at its upper part with a cock, and when the
operation is finished this cock is opened, and the pressure which exists inside the
vessel A forces the liquid up the pipe and through a refrigerator or condenser into
another vessel which admits of that portion of the sulphido of carbon which has not
been acted upon being removed. From thence the liquid is run into a double-
bottomed cast-iron vessel heated by steam at one hundred and twenty-five degrees
cent.
In Fig. 1 the steam boiler B is supported by the standards F, F, and is attached
to the vessel A. by the rods G, G, which pass through the collar or flange C.
The evaporation is stopped when the temperature of the liquid reaches one
hundred and twenty degrees cent. The solution of sulphocyanide of ammonium
with the addition of the necessary quantity of quicklime, is introduced into an
apparatus for the purpose of taking up the ammonia contained in the sulphocyanide
of ammonium, and which represents half of the total quantity of ammonia employed
in the process; the sulphocyanide of ammonium is thus transformed into the
sulphocyanide of lime.
The apparatus required for this purpose is shewn in longitudinal section at
Fig. 2, and is composed of two close vessels or boilers A and B, one placed above
the level of the other, and heated by the samo fire-place G, and each is provided
with a stirrer or agitator F, F¹.
The two vessels are half filled with the mixture of sulphocyanide of ammonium
and of lime, and when the lower boiler A is heated, the gas or vapour evolved will
pass through a coil of tubo C plunged in the liquid of the second vessel B.
The steam which is carried over with the gases will be condensed by imparting
its heat to the contents of the vessel B, and the gas which will be thereby disengaged
will be carried by a pipe D to the first vessel A, and will become mixed with the
ammonia contained in this vessel. The same fire-place G heats the two vessels A
and B, and the ammoniacal gas is conducted alternately to two sheet-iron pans
which contain the ordinary ammonia of commerce, of the strength of seventeen per
cent. of NH. These pans are provided with refrigerating apparatus, and a graduated
liquid gauge being adapted thereto, the progress of the saturation may be watched.
By this means the concentrated ammonia necessary for the success of the process
is obtained.
This apparatus may be employed for the manufacture of solution of ammonia
from ammoniacal salts.
When the thermomoter (which is plunged in the liquid in the lower vessel A)
marks one hundred and fifteen degrees cent., the vessel is emptied by opening
the cock on the drawing-off tube E. It is then filled again with the liquid con-
tained in the upper vessel B (by means of a pipe not shewn in the Drawing), and
this latter is then charged with fresh liquid. By this means the operation is made
continuous, and admits of nearly the whole of the ammonia being extracted from
the solution.
It is scarcely necessary to say that when it is desired to prepare the sulphocyanide a
of ammonium itself for sale, it will only be necessary to leave the liquid that has
been evaporated at one hundred and twenty-five degrees cent. to crystallize, when a
perfectly pure salt in the form of crystals will be obtained.

page_text: The sulphocyanide of lime serves as a medium in the manufacture of other
sulphocyanides.
It will only be necessary in fact to add a carbonate or some soluble sulphate,
to obtain at once a deposit or precipitate of sulphate or carbonate of lime, and a
solution of the new sulphocyanide.
In order to obtain a sulphocyanide of potassium, a concentrated solution of
sulphate of potass filtered and evaporated must be added to the solution of sulpho-
cyanide of lime.
The following is the process now adopted for converting the sulphocyanide of
potassium and sulphocyanides in general into ferrocyanides. An intimate mixture
is made of six equivalents of sulphocyanide of potassium in a perfectly dry state,
with five equivalents of lime, five equivalents of carbon, and one equivalent of iron
in a finely divided state, obtained by reducing by means of carbon the residue of
pyrites of good quality in an apparatus in which the iron may be reduced, without
coming in contact with the air. This mixture of dry materials is heated to
redness, and the following re-action take place
6 KSCN+5 CaO+5C+Fe=FeS+a CaS+5 CO+6KCN.
It will only be necessary to treat the mass when cold with water at the ordinary
temperature, in order to obtain a solution of ferrocyanide of potassium, wbich will
be formed according to the following equation:-
FeS+6KCN=KS+K_FeC®NG
The solution thus obtained is concentrated and left to crystallize, when it will
furnish fine crystals of ferrocyanide of potassium in abundance.
The apparatus for obtaining the iron in a finely divided state from the residue of
pyrites, is shewn in vertical section at Fig. 3, and in horizontal section at Fig. 3ª,
It consists of a cylinder A, the sides of which are heated by a suitable fire-place F.
The bottom of the cylinder A is movable, and being mounted on a hinge, is capable
of being drawn back by means of a sector rack C and pinion, so as to let the
contents of the cylinder drop into a hopper B, and be conducted from thence to a
close vessel D, mounted on the trolly E provided with wheels, so that the pyrites
may be withdrawn from the cylinder, removed away, and allowed to cool without
being brought in contact with the air.
Having now described the Invention that has been communicated to me by my
foreign correspondent, and having explained the manner of carrying the same into
effect,
I claim as the Invention secured to me by Letters Patent as aforesaid,―
The synthetical method or process herein set forth for manufacturing sulpho-
cyanides and ferrocyanides.
I also claim the apparatus herein shewn and described for the manufacture of
these products.
In witness whereof, I, the said William Edward Newton, have hereunto set
my hand and seal, the Seventeenth day of September, in the year of our Lord
One thousand eight hundred and seventy-eight.