Improvements in or connected with Apparatus for the Manufacture of Potassium Chlorate or Sodium Chlorate by Electrolysis.
Year: 1898

page_text: Date of Application, 18th Apr., 1898
Complete Specification Left, 18th Jan., 1899-Accepted, 18th Feb., 1899
Improvements in or connected with Apparatus for the Manufacture of
Potassium Chlorate or Sodium Chlorate by Electrolysis.
We, JOHN BROCK, a Director of the United Alkali Company Limited, of G",
Exchange Buildings, Liverpool, in the County of Lancaster, and the said UNITED
ALKALI COMPANY LIMITED, do hereby declare the nature of this invention to be
as follows:-
This invention relates to apparatus for the manufacture of potassium chlorate
or sodium chlorate and more particularly to apparatus for which a Patent dated
August 12th 1893 No. 15396 has been granted to Ferdinand Hurter of Liverpool.
The said apparatus consisted of metal cells or vessels coated inside with porous
material each vessel constituting a cathode and having a platinum anode suspended
therein. These cells or vessels were superposed and insulated one from another
and it was found that in case of any one of the lower cells or vessels requiring to
be repaired it was neessary to dismantle the whole apparatus above the cell or
vessel in order to effect such repair.
The present invention has for its object to utilise the electric current more
efficiently in the manufacture of potassium chlorate or sodium chlorate by elec-
trolysis and to enable repairs to the cells or containing vessels to be more readily
carried out than hitherto.
In the apparatus according to the present invention metal cells are provided
preferably made of cast iron, which are arranged in terraces. This arrangement
enables each individual cell to be readily inspected and removed when any repairs
are necessary without having to dismantle the whole apparatus thereby economizing
labour.
The cells are coated on the inside with a suitable porous lining and in order
to give the lining the necessary durability, cells which are round or oval in trans-
verse section are preferably employed.
In carrying out the invention, rows of these cells are arranged in terraces as
aforesaid and the cells, are filled with a solution of potassium or sodium chloride,
to which the necessary quantity of the corresponding caustic alkali has been
added, the solutions being maintained at a suitable temperature of from 60° to
80° Centigrade by any suitable means. For the anode in each cell a platinum
sheet or plate is used, the metallic vessel acting as the cathode. The electric
current is conducted from the positive terminal of any suitable source of electricity
into the solution by means of wires connected to the platinum sheet of the first
row of cells, the current passing thence through the solution and through the
porous lining into the walls of the metallic cells which are connected by means
of wires to the platinum sheets of the next row of cells and so on until the
current has traversed the whole series of cells finally leaving the walls of the last
row of cells by wires which are connected to the negative terminal of the
source of electricity. The solution of potassium chloride or sodium chloride is
caused to enter the cells or vessels at the top of the terrace and after flowing in

page_text: succession through the whole series of vessels by overflow pipes is drawn off at
the bottom of the terrace and in the case of potassium chloride having been
used the liquor drawn off is run into suitable crystallizers and allowed to crystallise.
When a solution of sodium chloride is used, the liquor drawn off is boiled down,
the unchanged sodium chloride which salts out being removed during the operation.
Dated this 18th day of April 1898.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.
Improvements in or connected with Apparatus for the Manufacture of
Potassium Chlorate or Sodium Chlorate by Electrolysis.
I, JOHN BROCK, a Director of The United Alkali Company Limited, of 30,
James Street (late of G, Exchange Buildings), Liverpool, in the County of
Lancaster, and the said UNITED ALKALI COMPANY LIMITED, do hereby declare
the nature of the said invention and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement:-.
This invention relates to apparatus for the manufacture of potassium chlorate,
or sodium chlorate, by electrolysis and more particularly to apparatus for which
Letters Patent dated 12th August 1893 No. 15,396 were granted to Dr. Ferdinand
Hurter. The said apparatus consists of metal cells, or vessels, coated inside with
porous material, each vessel constituting a cathode and having a platinum anode
suspended therein. The said cells, or vessels, are superposed and insulated one
from another and in case of any one of the lower cells, or vessels, requiring to
be repaired, it is necessary to dismantle the whole apparatus above the cell, or
vessel, to be repaired in order to effect such repair.
The present invention has for its object whilst utilising the electric current
very efficiently in the manufacture of potassium chlorate, or sodium chlorate, by
electrolysis, to enable repairs to the cells, or containing vessels, to be more
readily carried out than hitherto.
We will describe this invention with reference to the accompanying drawing
which shews in section apparatus made according to this invention.
In the apparatus we provide metal cells or vessels A, preferably made of cast
iron, which are arranged in terraces B, as shewn in the said drawing. This
arrangement enables each individual cell, or vessel, to be readily Inspected and
removed, when any repairs are necessary, without having to dismantle the whole
apparatus, thereby economising labour.
The cells or vessels A are coated on the inside with a suitable porous lining a,
and in order to give the lining the necessary stability we preferably employ
cells, or vessels, which are round, or oval, in transverse section.
In carrying this invention into practical effect we arrange rows of these cells,
or vessels A, in terraces B, as aforesaid, and the said cells, or vessels, are filled
with a solution of potassium chloride, or sodium chloride, to which the necessary
quantity of the corresponding caustic alkali has been added, the solutions being
maintained at a temperature of from 60° to 80° Centigrade by any suitable means.
For the anode in each cell a platinum sheet, or plate, A¹ is used, the metallic
cell, or vessel A acting as the cathode. The electric current is conducted from
the positive terminal of any suitable source of electricity into the solution by
means of wires connected to the platinum sheets of the first row of cells, or
vessels, the current passing thence through the solution and through the porous

page_text: linings a, into the walls of the metallic cells, or vessels, which are connected by
means of wires to the platinum sheets of the next row of cells, or vessels, and
so on until the current has traversed the whole series of cells, or vessels, finally
leaving the walls of the last row of cells, or vessels, by wires which are connected
to the negative terminal of the source of electricity. The solution of potassium
chloride, or sodium chloride, is caused to enter the cells, or vessels, at the top
terrace and, after flowing in succession through the whole series of cells, or
vessels, by the overflow pipes C, is drawn off, at the bottom terrace, by the pipe
C', and, in the case of potassium chloride having been used, the liquor drawn
off from the pipe C¹ is run into any ordinary or suitable crystallisers and allowed
to crystallise. When a solution of sodium chloride is used, the liquor drawn off
is boiled down, the unchanged sodium chloride, which salts out, being removed
during the operation.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
Apparatus for the manufacture of potassium chlorate, or sodium chlorate, by
electrolysis consisting of metallic cells, or vessels, constituting cathodes and
having porous linings, and platinum anodes the said cells or vessels being
arranged in terraces one above another and being provided with overflow pipes
for the passage of solution downwards, through the series of cells or vessels each
of the said cells, or vessels, being electrically connected to the anode element of
the adjacent cell, or vessel, throughout the series; substantially as herein before
described and illustrated by the accompanying drawing.
Dated this 18th dar of January 1899
JOHNSONS & WILLCOX,
47. Lincoln's Inn Fields, London, W.C., Agents.