Improvements in Means for the Electrolytic Generation of Chlorine and Compounds of Chlorine with Earthy Bases, More Especially Intended for Bleaching Purposes.
Year: 1890

page_text: Date of Application, 23rd Jan., 1890
Complete Specification Left, 23rd Oct., 1890--Accepted, 27th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in Means for the Electrolytic Generation of Chlorine
and Compounds of Chlorine with Earthy Bases, More Especially
Intended for Bleaching Purposes.
We DESMOND GERALD FITZ-GERALD of 46 Loughborough Road Brixton in
the County of Surrey, Electrician and ALEXANDER CROIL FALCONER of
9 Dalmeny Road Tufnell Park in the County of Middlesex Merchant do hereby
declare the nature of this invention to be as follows:-
Our invention relates to means for the electrolytic generation of chlorine and
compounds of chlorine with carthy bases thereby producing fluids possessing strong
bleaching properties although the invention is not limited to bleaching operations.
The conductors hitherto used as anodes in the electrolysis of chlorides in solution
have hitherto been carbon and platinum. According to our invention we employ
anodes of peroxide of lead in the compact coherent and conductive form in which it
is known as lithanode.
This substance offers the advantages of being (unlike platinum) absolutely
unattackable by chlorine and if not being (like the various forms of carbon) liable
to disintegration by the effect of the electrolysis. We employ as electrolytes
solutions of any suitable earthy chloride such as the chloride of calcium or of
magnesium or a solution containing a mixture of earthy chlorides. An earthy
chloride (riz. chloride of calcium) was specified for use in the production of bleaching
fluids by one of the present applicants in the Specification of Letters Patent No. 1376
of 6th May 1872.
The anodes should be of large surface and are preferably made by attaching
a number of plates of compact peroxide of lead or lithanode to a support of wood
or other suitable material; the said plates being connected (which may be done by
means of platinum washers and wires well insulated) to a conductor preferably of
lead or an alloy of lead insulated and embedded in the support.
In bleaching we prefer to arrange the anodes at or near the bottom of the tank
with the double object of utilizing for bleaching purposes the free chlorine generated
and of maintaining the anodes in contact with an earthy body which will combine
with any free acid fiberated and also with a portion of the chlorine evolved.
For cathodes we may use metal sheets preferably copper or zinc corrugated.
We may construct the bleaching tank with a false bottom in such manner as to
allow of the matter to be bleached being introduced within the solution without
coming into contact with the anodes.
Dated this 23rd day of January 1890.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
Improvements in Means for the Electrolytic Generation of Chlorine
and Compounds of Chlorine with Earthy Bases, More Especially
Intended for Bleaching Purposes.
We, DESMOND GERALD FITZ-GERALD of 46 Loughborough Road Brixton in
the County of Surrey Electrician and ALEXANDER CROIL FALCONER of
9 Dalmeny Road Tufnell Park in the County of Middlesex Merchant 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 means for the electrolytic generation of chlorine and

page_text: compounds of chlorine with earthy bases (hypochlorites and chlorates) thereby
producing fluids possessing strong bleaching properties although the invention is
not limited to bleaching operations. The conductors hitherto used as anodes in
the electrolysis of chlorides in solution have been carbon and platinum.
According to this invention we employ anodes of peroxide of lead in the compact
coherent and conductive form in which it is known as lithanode the preparation of
which lithanode is described in the Specifications of Letters Patent No. 4671
of 15th April 1885 and No. 16608 of 17th December 1886 granted to one of the
present applicants namely the said Desmond Gerald Fitz-Gerald. This substance
offers the advantages of being (unlike platinum) absolutely attackable by chlorine
and of not being (like the various forms of carbon) liable to disintegration by the
effect of the electrolysis. We employ as electrolytes solutions of any suitable
earthy chloride such as the chloride of calcium or of magnesium, or a solution
containing a mixture of earthy chlorides. An earthy chloride (riz. chloride of
calcium) was specified for use in the production of bleaching fluids by one of the
present Applicants (the said Desmond Gerald Fitz-Gerald conjointly with Bernard
Charles Molloy) in the Specification of Letters Patent No. 1376 of 6th May 1872.
The anodes should be of large surface and are preferably made by attaching a
number of plates of the said compact coherent and conductive peroxide of lead, or
lithanode to a support of wood or other suitable material the said plates being
connected (which may be done by means of platinum washers and wires well insulated)
to a conductor, preferably of lead or an alloy of lead, insulated and embedded in the
support.
In bleaching we prefer to arrange the anodes at, or near, the bottom of the tank
with the double object of utilizing for bleaching purposes the free chlorine generated
and of maintaining the anodes in contact with an earthy body which will combine
with any free acid liberated and also with a portion of the chlorine evolved. For
cathodes we may use metal sheets preferably copper or zinc corrugated.
We may construct the bleaching tank with a false bottom in such manner as to
allow of the matter to be bleached being introduced within the solution without
coming into contact with the anodes.
Having now particularly described and ascertained the nature of our said inven-
tion and the manner in which the same is to be performed we declare that what
we claim is :-
In the electrolytic generation of chlorine and compounds of chlorine with earthy
bases the use of the aforesaid compact coherent and conductive peroxide of lead or
lithanode as an anode in the electrolysis of earthy chlorides substantially as herein-
before described.
J. H. JOHNSON & Co.,
Agents.