Improvements in Electrolytic Cells and Diaphragms.
Year: 1892

page_text: Date of Application, 10th Oct., 1892
Complete Specification Left, 10th July, 1893-Accepted, 10th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in Electrolytic Cells and Diaphragms.
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:-
Our improvements relate :-
First. To the formation of electrolytic cells or diaphragms of wire gauze or
perforated metal upon which we deposit any suitable fibre, such as asbestos, or
vegetable fibres in the form of pulp so as to form what may be called a kind of
paper or felt adhering to the said gauze or perforated metal.
Second. To the deposition on paper or felt, for the purposes above named,-of
porous stone-like material such as Portland cement, plaster of paris, or a mixture
of clay and silicate of soda.
Third. To the deposition, in some cases, of the said porous, stone-like material
directly upon the said gauze or perforated metal without the intervention of fibrous
materials.
DL OL
_ 1000
Per pro J. T. KING,
W. B. Johnson,
Agent.
Improvements in Electrolytic Cells and Diaphragms.
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 electrolytic cells and diaphragms, especially those
intended for use in the production of soda or other alkalies by the decomposition
of their salts.
The accompanying diagram shows in vertical section electrolytic apparatus
embracing a diaphragm manufactured in accordance with our improved method.
A is a vessel containing a cell B, which is formed of asbestos, vegetable or other
suitable fibre C deposited in the form of pulp upon wire gauze or perforated sheet
metal; the latter acting as an electrode. The fibrous material being deposited in
the form of pulp consequently adheres to the wire gauze or perforated metal. On
the layer C there is deposited a layer D of porous stone-like material, such as
Portland cement, plaster of paris, or a mixture of clay and silicate of soda. The
layers C and D constitute the diaphragm. E is the carbon anode. F is the
sodium chloride solution. G is the caustic soda solution.
That part of the diaphragm in contact with the cathode B should be as porous
as possible, and for this reason the layer of fibrous material C is interposed between
the cathode and the layer of stone-like material D. The hydrogen generated on
the surface of the cathode is, under such circumstances, more readily liberated than
if the cathode were embedded in a solid substance. In some cases, however, the

page_text: layer D of stone-like material may be deposited directly on the wire gauze or
perforated metal cathode without the 'intervention of the layer C of fibrous
material.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we claim:
1. For use in electrolytic apparatus, a cathode formed of wire gauze or
perforated metal and having deposited on the anode side thereof and in the form
of pulp the material constituting the porous diaphragm.
2. For use in electrolytic apparatus, a porous diaphragm, consisting of a layer
of fibrous material C next the cathode, and a layer of stone-like material D
deposited on the fibrous material, substantially as berein described.
3. For use in electrolytic apparatus, a porous diaphragm consisting of a layer
of stone-like material deposited on the anode side of a cathode formed of wire
gauze or perforated metal.
4. The improved method of making the diaphragm of an electrolytic cell,
substantially as herein described, and consisting in depositing on the electrode
the materials whereof the diaphragm is made while in the form of pulp.
Dated the 10th day of July 1893.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.