Improvements in Apparatus for Electrolysis of Alkali Salts with Quicksilver as Cathode.
Year: 1895

page_text: Date of Application (in United Kingdom), 27th May, 1895
Complete Specification Left, 27th May, 1895-Accepted, 3rd Aug., 1895
COMPLETE SPECIFICATION.
Improvements in Apparatus for Electrolysis of Alkali Salts with
Quicksilver as Cathode.
I, HENRIK CHRISTIAN FREDRIK STORMER commonly known under the name
of Fredrik Störmer of 5 Zetlitzgade, Christiania, Norway, 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:
The apparatus in question is constructed with the view to prevent in an absolutely
certain manner that the amalgam formed by contact with the electrolyte liquid
shall take up oxygen from the water and be lost in the formation of secondary
products. For this purpose the quicksilver is made to circulate between the
electrolysis vessel and another vessel in which the amalgam is freed from the alkali
metal while at the same time the particles of quicksilver are kept in constant motion
among themselves either so that the whole mass oscillates or so that a kind of
stirring or oscillating motion of the particles takes place.
This is for the purpose of moving the particles among themselves. This motion
must however not be so strong that the surface skin of the quicksilver where the
amalgamation takes place be broken through, because it is important that the liquid
particles shall not pierce this skin and oxydize the alkali metal.
The drawing illustrates by an example of construction how the invention may be
practically carried out. Fig. 1 is a longitudinal section and Fig. 2 a cross section
of an apparatus; the other figures are details and modifications.
A is the electrolysis vessel containing for instance chloride of sodium. In the
same below the liquid surface are suspended or in other suitable manner arranged
one or more flat pans or gutters B. These gutters are here as an example suspended
by rods C carried by a shaker spindle with cam wheel D which puts the gutters into
a shaking vertically vibrating motion. The shaking device or moving device may
also be made so as to produce horizontal motion.
The gutters contain quicksilver which by a pipe conduit I is conveyed to
the uppermost gutter and thence into and out of the other gutters, for instance
as here shewn, the pipes in this case being flexible tubing. K is the outlet.
F is the inlet and G the outlet for the electrolyte. L is the outlet for the
chlorine gas.
The negative pole is connected to the quicksilver while the positive pole pieces H
are placed over the gutters. The amalgam formed will by the motion distribute
itself evenly in the quicksilver and in a concentrated form run off from the lowest
gutter in order outside of the apparatus to be freed from the alkali metal, and the
quicksilver then enters purified into the circulation again.

page_text: The bottom of the gutters are by preference provided with grooves or ridges as
shown here as an example.
The desired mixing of the quicksilver may also be produced by making the
gutters fixed but provided in the bottom with plates which may either be grooved
or have the form of a grid or sieve or perforated plate, see Fig. 3, or a plate or
false bottom with ridges, see Fig. 4. These plates then in some suitable manner
receive motion either up and down or back and forth, and the motion may either be
a shaking one or a slow and quiet one. Fig. 34 shews a vessel fitted with perforated
plate B₁ which is worked up and down in the mercury pan B at the bottom of the
vessel A by the rod C. F is the inlet and G the outlet for the electrolyte. I is the
inlet for the mercury and K the outlet by a flexible tube for changing the height of
pressure. Lis the outlet for the chlorine gas. The anodes H are suspended over
the quicksilver as shown.
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. In that kind of electrolytical apparatus for the separation of alkali salts where
the cathode consists of quicksilver which circulates from the electrolysis vessel to
another vessel wherein the amalgam is freed from the alkali metal, so arranging the
part or parts wherein the quicksilver is covered by the electrolyte that they either
themselves are connected to a moving device or are provided with one or more loose
plates or the like submerged in the quicksilver and connected to a moving device,
all for the purpose of keeping the particles of quicksilver and of amalgam mutually
in motion, but so that the surface skin of the quicksilver be not broken where the
amalgamation takes place.
2. The constructions of apparatus described with reference to the accompanying
drawings.
571 1
100K
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.