Improvements in or connected with Apparatus for the Manufacture of Chlorate of Potash by Electrolysis.
Year: 1893

page_text: Date of Application, 12th Aug., 1893
Complete Specification Left, 12th May, 1894-Accepted, 16th June, 1894
TRUYIDIONAL DEDIFICATION.
Improvements in or connected with Apparatus for the Manufacture
of Chlorate of Potash by Electrolysis.
I, FERDINAND HURTER of Holly Lodge Cressington Park, Liverpool in the
County of Lancaster, Chemist do hereby declare the nature of this invention to
be as follows:-
T
My invention has for its object to effect the better utilization of the electric
current in the manufacture of chlorate of potash by electrolysis so as to obtain a
better yield and also to avoid frequent repairs to the cells or containing vessels.
According to my invention I provide metal cells or containing vessels preferably
made of cast iron. These vessels I paint or coat inside with a mixture of Portland
cement, salt sand and water. When this mixture has set hard I repeat the
operation of coating until the layer of cement has become sufficiently thick. When
the cement has set I fill the vessel with water to extract all the salt and thus I
obtain a very firm but porous lining which is not acted upon by the solution to be
afterwards used.
I place a number of these cells in series using the wall of the cell as a cathode
connecting it to the anode of the next cell of the series. As anodes I use sheets of
platinum.
Into these cells is introduced a solution of potassium chloride rendered alkaline
with caustic potash and kept at a suitable temperature. I conduct the electric
current from the positive terminal of any suitable source of electricity into the
solution by means of sheets of platinum, the current then passes through the solution
and through the porous lining into the walls of the metallic cell (which is connected
to the platinum sheets of the next cell for example by metallic wires or cables) and
80 on until the current leaves the series through the walls of the last cell which are
connected to the negative terminal of the source of electricity.
I prefer to place the several cells forming a series one above the other taking
care to place insulating material between any two of the cells so that they are not
in metallic contact. I attach the sheets of platinum which serve as anodes in a
lower cell directly to the bottom of the cell immediately above it and I provide
circulating pipes or passages so that the solution can flow from compartment to
compartment. Care must be taken that these pipes or passages do not form false
connections which are best avoided by using pipes of nonconducting material such
as glass or ebonite or the like.
Dated this 12th day of August 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Apparatus for the Manufacture
of Chlorate of Potash by Electrolysis.
I, FERDINAND HURTER Ph.D. of Holly Lodge Cressington Park Liverpool
in the County of Lancaster 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 :-
My invention has for its object to effect the better utilisation of the electric

page_text: I
current in the manufacture of chlorate of potash by electrolysis so as to obtain a
better yield, and also to avoid frequent repairs to the cells, or containing vessels.
I will describe my invention with reference to the accompanying drawings.
According to my invention I provide metal cells, or containing vessels, as shown
at A, for example, in Figure 1, preferably made of cast iron. These vessels I
paint, or coat, inside with a mixture of Portland cement, salt, sand, and water.
may use equal volumes of good and dry cement, and of dry common salt, but I prefer
to use less salt; say one volume of salt to two volumes of Portland cement. I may
add a small quantity of sand to this or I may use good Portland cement and
salt only. When this mixture has set hard I repeat the operation of coating until
the layer of cement has become sufficiently thick say one quarter to half an inch
When the
thick. I prefer a thin layer. The lining thus formed is shown at B.
cement has set I fill the vessel with water to extract all the salt, and thus I
· obtain a very firm but porous lining which is not acted upon by the solution to be
afterwards used.
In order to give to the cement durability it is advisable to use cells of round or
oval transverse section since from plane surfaces the cement has a tendency to
peel off owing to the evolution of hydrogen gas on the iron surface, which must
escape through the porous cement.
I place a number of these cells in series using the walls of the cells as cathodes
and connecting each of them to the anode of the next cell of the series. As anodes
I use sheets of platinum as shown at C. Into these cells is introduced a solution
of potassium chloride rendered alkaline with caustic potash and kept at a suitable
temperature such as a temperature of from 60° to 80° centigrade. This may be
effected by steam coils in the cells, or in any other convenient way, but the heating
effect of the current itself is normally sufficient. I conduct the electric current
from the positive terminal of any suitable source of electricity into the solution by
means of the sheets of platinum, the current thence passing through the solution,
and through the porous lining of cement, into the walls of the metallic cell, (which
is connected to the platinum sheets of the next cell either directly, or otherwise, for
example by metallic wires, or cables,) and so on until the current leaves the series
through the walls of the last cell which are connected to the negative terminal of
the source of electricity.
I prefer to place the several cells forming a series one above the other as shewn
in Figure 2 taking care to place insulating material between any two of the cells,
and between the top cell and its cover, as shewn at D, so that they are not in
metallic contact. I attach the sheets of platinum C which serve as anodes in the
lower cells directly to the bottom of the metal of the cell immediately above it
as shown at c the top anode being similarly attached to the cover and I provide
pipes or passages E so that the solution can flow continuously from compartment
to compartment. Care must be taken that these pipes or passages do not form
false connections which are best avoided by using pipes of nonconducting material
such as glass or ebonite or the like and by insulating the pipes by passing them
through insulating stoppers as at F. The upper ends of these pipes should be at
such a level below the lowermost part of the iron of the cell or cover above that
liquid will not touch the iron of the cell or cover above. G is the inlet for the
solution and H is the outlet or overflow pipe and I are the gas outlets.
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 :-
1. For use in the manufacture of chlorate of potash by electrolysing a solution
of potassium chloride, an apparatus consisting of a metallic vessel, lined with a
cement mixture formed as described so as to constitute a porous lining, the metallic
vessel forming the cathode, the anode being formed of a sheet, or sheets, of
platinum, substantially as hereinbefore described.
2. For use in the manufacture of chlorate of potash by electrolysing a solution

page_text: of potassium chloride, an apparatus consisting of superposed metallic vessels,
insulated from each other, and lined with a cement mixture formed so as to be
porous as described, the said metallic vessels constituting cathodes and having
platinum anodes secured to the said vessels (except the upper anode of the series).
substantially as herein before described.
3. For use in the manufacture of chlorate of potash by electrolysing a solution
of potassium chloride, an apparatus, constructed, and arranged, substantially as.
hereinbefore described and illustrated by the accompanying drawings.
Dated this 12th day of May 1894.
JOHNSONS & WILLCOX,
Agents.