Improvements in Obtaining Cyanides and Ferrocyanides.
Year: 1894

page_text: Date of Application, 3rd Apr., 1894
Complete Specification Left, 30th Oct., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Obtaining Cyanides and Ferrocyanides.
I, JAMES BURGESS READMAN, D.Sc., of 4, Lindsay Place, Edinburgh, in the
County of Mid Lothian, North Britain, Analytical and Consulting Chemist, do
hereby declare the nature of this invention to be as follows, that is to say :-
My said invention has for its object the obtainment of cyanides and ferrocyanides
in an improved manner and without the waste of materials and the rapid
destruction of apparatus which have rendered many attempts with the same
objects practically unsuccessful.
In carrying out my invention I take a mixture of carbonaceous matter with any
one or more of the following substances or compounds, namely alkalies or alkaline
earths, such as oxides of potassium, sodium, barium, strontium, or calcium, or their
carbonates or other suitable salts or the said metals, and I subject the the mixture
to a high temperature in presence of nitrogen or of a gaseous or other mixture
containing or yielding nitrogen. And in order to apply the requisite high
temperature economically and effectually without rapidly injuring the vessel or
apparatus containing the mixture, I cause the heat to be generated within the
vessel or apparatus by directing a powerful electric current to act on the materials
by means of carbon or other suitable electrodes as is done in electrical furnaces
used for other purposes.
The furnace or vessel employed may be of any convenient simple form, such as a
short vertical retort, made with a charging door at the top and with a tapping
outlet at the lower part, and also with inlet and outlet pipes for the nitrogen or
gaseous mixture containing nitrogen.
For
The materials consisting of the carbonaceous matter and alkali or other base or
bases are intimately mixed or incorporated, and are heated if necessary, to expel
volatile matters. The mixture is then put into the retort, and the nitrogenous gas
being made to flow through the retort, the electric current is turned on.
supplying the nitrogen air which has been more or less deoxidised or deprived of
free oxygen may be employed; or what is known as producer gas may be used,
such gas being still available as gaseous fuel after passing through the electrical
furnace.
In cases in which more or less of the cyanide formed is volatilised the gases
leaving the retort must be passed through collecting, condensing, or absorbing
apparatus to recover the cyanide from them.
If a ferrocyanide is to be obtained, the necessary proportion of iron or of a
suitable salt or compound thereof must be present in the mixture of materials
operated on. Or the cyanide obtained as herein before described may be converted
into ferrocyanide by known means.
Dated this Second day of April 1894.
EDMUND HUNT,
Applicant's Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Obtaining Cyanides and Ferrocyanides.
I, JAMES BURGESS READMAN, D.Sc., of 4 Lindsay Place, Edinburgh, in the
County of Mid Lothian, North Britain, Analytical and Consulting Chemist, do
bereby 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, that is to say :-
My said invention has for its object the obtainment of cyanides and ferrocyanides
in an improved manner and without the waste of materials and the rapid destruction
of apparatus which have rendered many attempts with the same objects practically
unsuccessful.
In carrying out my invention I take a mixture of carbonaceous matter with any
one or more of the following substances or compounds, namely, alkalies or alkaline
earths, such as oxides of potassium, sodium, barium, strontium, or calcium or their
carbonates or other suitable salts, or the said metals, and I subject the mixture to
a bigh temperature in presence of nitrogen, or of a gaseous or other mixture
containing or yielding nitrogen. And in order to apply the requisite high
temperature economically and effectually without rapidly injuring the vessel or
apparatus containing the mixture, I cause the heat to be generated within the vessel
or apparatus by directing a powerful electric current to act on the materials by
means of carbon or other suitable electrodes as is done in electrical furnaces used
for other purposes.
The furnace or vessel employed may be of any convenient simple form and
made with one or more charging doors at the top and with a tapping outlet at the
lower part, and also with inlet and outlet pipes for the nitrogen or gaseous mixture
containing nitrogen. In order, however, that my said invention and the manner of
performing the same may be properly understood 1 hereunto append a sheet of
explanatory drawings to be hereinafter referred to and representing apparatus
designed for use in carrying out my invention.
Figures, 1, and, 2, of the drawings are a plan and a side elevation of the
apparatus and Figures, 3, and, 4, are horizontal and vertical sections.
In these drawings the same reference letters are used to mark the same or like
parts wherever they are repeated.
The furnace chamber, A, is formed within a vertical-cylindrical iron casing, B,
which is lined with firebrick, C, and has an inner lining of hard carbon, D. The
furnace is covered by an iron plate, E, having at its centre a stuffing box, F,
through which a carbon rod, G, forming one of the electrodes is entered down into
the furnace. In order to insulate the carbon rod, G, the lining and gland of the
stuffing box, F, are made of porcelain and are packed with asbestos; whilst to
make more certain of having complete insulation a sheet of asbestos is interposed
between the cover plate, E, and walls of the furnace. For charging the materials
into the furnace two diametrically opposite hopper inlets, H, are provided, these
being fitted with valves, J, ordinarily held shut by counterweighted levers. In
charging, the part of each hopper, H, above the valve, J, is filled and a cover, K,
having been put on the valve, J, is opened to allow the materials to drop into the
furnace. The nitrogen, or gaseous mixture containing nitrogen enters the furnace
at the same inlets as the materials, the main pipe, L, supplying it being connected
by branches to the two inlet pieces, H.
A carbon rod, M, forming the second electrode enters up the furnace through a
stuffing box, N, in the bottom plate, P, of the casing. A tapping outlet, Q, is
formed through one side at the bottom of the furnace, and from it the fused
cyanide produced is delivered into a receptacle, R, placed within a casing, S,
provided to prevent oxidising action of the air on the cyanide whilst hot.
At a

page_text: point which is, preferably, opposite to the tapping outlet, Q, an outlet, T, is
provided for gaseous residues; and sight holes, U, with covers may be provided in
suitable positions to allow of the condition of the interior being inspected from
time to time.
The materials consisting of the carbonaceous matter and alkali or other base or
bases are intimately mixed or incorporated, and are heated, if necessary, to expel
volatile matters. For example, I take 100 pounds of dry ground carbonate of
barium and mix it intimately with about 20 pounds pulverised carbon such as oil,
coke, or wood charcoal; and I introduce the mixture into the furnace containing
coke already brought to a state of incandescence by the electric current. For
supplying the nitrogen air which has been more or less deoxidised or deprived of
oxygen may be passed through the furnace; or what is known as producer gas may
be used, the residue of such gas being still available as gaseous fuel after passing
through the electrical furnace. As a result of the operation a large portion of the
original carbonate of barium becomes converted into cyanide of barium which
becoming fused runs to the bottom of the furnace and can be tapped out through
the outlet, Q, periodically.
In cases in which more or less of the cyanide formed may be volatilised the
gases leaving the retort by the outlet, T, must be passed through collecting
condensing, or absorbing apparatus to recover the cyanide from them.
If cyanide of potassium or other particular cyanide is required, another cyanide
such as cyanide of barium having for convenience, been formed, in the process
hereinbefore described, the cyanide so formed may be converted into the required
cyanide by well known means. Or the cyanide obtained as herein before descrit d
may be converted into ferrocyanide by known means.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
In processes for obtaining cyanides and ferrocyanides by heating a mixture of
carbonaceous matter and carbonate of barium or other herein before specified alkali
or alkaline earth or compound thereof, in the presence of nitrogen, the applying of
the requisite high heat by means of the electric arc, acting internally on the
materials substantially in the manner and for the purposes herein before described.
Dated this Twenty-ninth day of October 1894
EDMUND HUNT,
Applicant's Agent.