Improvements in the Production of Alkali, and in Apparatus therefor, the said Apparatus being applicable for Electrolysis generally.
Year: 1893

page_text: Date of Application, 10th Mar., 1893
Complete Specification Left, 11th Dec., 1893-Accepted, 10th Mar., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Production of Alkali, and in Apparatus
therefor, the said Apparatus being applicable for Electrolysis
generally.
We JAMES HARGREAVES of Farnworth-in-Widnes in the County of Lancaster,
Chemical Engineer, and THOMAS BIRD of Cressington near Liverpool in the
County of Lancaster, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
The object is to facilitate the production of alkali, and to provide improved
apparatus for use in electrolysis.
First. The improvement in the production of alkali consists in subjecting a
solution say of chloride of sodium on one side of a porous diaphragm to the action
of an electric current whilst a gas such as air carbonic acid gas and moisture act on
the opposite side of the diaphragm.
Second. In cases where the cathode becomes polarized we place in connection
therewith any suitable metallic oxide such as oxide of copper or catalytic material
such as platinum together with oxygen, or oxidizing material.
Third. Carbonic acid gas given off by the generator of power for the production
of electricity is used as the gas above mentioned when suitable.
Fourth. Moisture under the first part is evaporated and conveyed into the cells
by aid of heated gas or air.
Fifth. Apparatus under our invention consists in a cell divided either horizontally
or vertically by a porous diaphragm, such diaphragm being of increased thickness
or decreased porosity from above downwards when the said diaphragms are more or
less vertical. One portion of the cell contains the liquid to be acted on, and the
anode, the other contains the moisture the gas and the cathode. A series of cells
or diaphragms may be used.
Dated this Ninth day of March 1893.
Per pro J. T. KING,
J. Johnson,
Agent.
COMPLETE SPECIFICATION.
Improvements in the Production of Alkali, and in Apparatus
therefor, the said Apparatus being applicable for Electrolysis
generally.
We,
, JAMES HARGREAVES, of Farnworth-in-Widnes, in the County of Lancaster,
Chemical Engineer, and THOMAS BIRD, of Cressington, near Liverpool, in the
same county, Electrical Engineer, 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 :-
This invention relates to the electrolytic method of obtaining alkalies, and to
apparatus adapted for use in carrying out that method and in electrolysis generally;
its objects being to facilitate the action of the apparatus and to render the same
more compact.
In carrying out our invention, we subject a solution, say of sodium chloride, on
one side of a porous diaphragm to the action of an electric current, while a gas,

page_text: such as air, and moisture act on the opposite or cathode side of the diaphragm.
Where the production of a carbonate is required, carbonic acid gas and moisture
may be admitted to the cathode side of the diaphragm. If a combustion engine be
employed for driving a dynamo for supplying the electric current, the carbonic acid
gas for acting on the alkali may be derived from the products of combustion given
off by the engine. The moisture required is evaporated and conveyed to the cell
by the aid of heated air or other gas.
In cases where the cathode becomes polarized, we apply thereto any suitable
metallic oxide, such as oxide of copper, of nickel or of manganese, or catalytic
material, such as platinum together with oxygen or an oxidizing substance.
The accompanying diagram represents in vertical section an electrolytic cell
constructed in accordance with our invention.
The containing vessel comprises two compartments A and A' separated by a flat
porous diaphragm B. C is a flat wire gauze cathode. D is the subdivided carbon
anode. E is the solution to be decomposed. F is the outlet for chlorine. G is the
inlet for steam, air, carbonic acid or other gas, which occupies the chamber H
beneath the cathode. J is the drain-pipe to the concentrator.
Flat vessels divided horizontally can be made of large size, and can be piled
up one on another to any convenient height, thus rendering the apparatus very
compact.
The vessels may, however, be divided vertically, if preferred. Under such
circumstances, the porous diaphragm may gradually increase in thickness or
decrease in porosity from the top downwards, in order to compensate for differences
of hydrostatic pressure, thus regulating the filtering effect.
It will be seen that the apparatus is of the type shown in the Specification of
our Letters Patent No. 18871 of 1892, inasmuch as the electrolytic cell is bounded
wholly or partially by a permeable cathode in juxtaposition with a porous diaphragm
or united to it.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we claim :-
-
1. In obtaining alkali by electrolysis in which an electrolytic cell bounded
wholly or partially by a permeable cathode is employed as described, admitting air
or other gas charged with moisture to the chamber containing the cathode, the
alkali being removed as a solution by the moisture which condenses on the
cathode.
2. An electrolytic vessel divided into two compartments by a flat porous
diaphragm in juxtaposition with or united to a permeable cathode, one compartment
containing an anode and the solution to be decomposed and the other comprising a
chamber for the steam, moistened air or other gas employed in removing the alkali
from the cathode, substantially as described with reference to the accompanying
diagram.
Dated the 11th day of December 1893.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.