Improvements in and Apparatus for Effecting Electrolysis.
Year: 1898

page_text: Improvements in and Apparatus for Effecting Electrolysis.
A communication from abroad by Messrs. SOLVAY & Co., of 25, Rue du Prince
Albert, Brussels, Belgium, Manufacturers.
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, W.C., in the County of
London, Consulting Engineer and Chartered Patent Agent, do hereby declare the
nature of this invention to be as follows:-
This invention relates to improvements in and apparatus for effecting in a
continuous manner the electrolysis of alkaline chlorides and other salts in the
presence of a mercury cathode. The electrolytic process is rendered continuous
by causing the metal liberated by electrolysis to combine with mercury, treating
the amalgam so produced in another part of the apparatus for the purpose of
regenerating the mercury therefrom, and returning the regenerated mercury to
the electrolytic apparatus for re-use. Heretofore it has been necessary to cause
large quantities of mercury to circulate, and this circulation has been effected
by making the whole apparatus movable and imparting to it a rocking motion;
or by constructing it with a slope and causing the mercury to flow down along
the bottom or in spiral channels; or by displacing the mercury by means of
plungers or pistons. The circulation has also been effected by means of pumps.
These arrangements have been such that if from any cause the movement of
the mercury is arrested, the apparatus will be deprived of mercury, although the
current continues to pass, so that more or less trouble arises.
It has been observed that the alkaline amalgam forms especially at the
surface of the mercury layer, and tends to remain there by reason of its lightness.
Now according to this invention the surface of the mercury containing amalgam
is continuously removed so as to continually present a fresh surface to the metal
being liberated thereon, whilst the deeper layer of mercury may remain more
or less at rest. For this purpose the electrolytic apparatus is so constructed
that the surface of the mercury shall be perfectly horizontal, and that the layer
of amalgam that is continually being formed when the apparatus is in action,
shall be caused to pass out therefrom through a surface-discharging device
arranged at one end.
The pure mercury is supplied at the opposite end at a deep part which also
forms a reservoir.
The improved apparatus thus contains no mechanical device whatever but is
simply a rectangular tank, which may be of any suitable length and width
without interfering with the regular movement of the layer of mercury. The

page_text: bottom may be horizontal or not, but always remains covered with mercury,
even when the supply is arrested. In order to empty it completely in case of
cleaning operations, it is inclined by means of a suitable screw or by means
of a cock placed at the lowest point. The mercury enters at one end and passes
out at the other end through the discharging device or overflow, the height of
which may be adjusted and which is designed to allow, more particularly, the
superficial layer (which is richest in alkaline metal) to pass off. The advantage
of this arrangement consists in that there is no limitation to a predetermined
discharge, as is the case in apparatus with inclined bottoms, and that any dis-
charge may be employed which is found to be the most advantageous without
affecting the proper utilization of the electric currents. In fact even solid
amalgam floating on the surface of the mercury might be produced as in this
apparatus its discharge does not present any difficulty, which is not the case in
apparatus heretofore employed.
With the object of promoting the circulation of this superficial layer, the
whole of the layer of liquid containing the salt in solution situated above such
layer may be caused to circulate also in the same direction.
In order to raise the discharged mercury up to the feeding level, a suitable
elevator is employed but it is obvious that a pump or any other mechanical
device might be used equally well.
Apparatus designed for regenerating the mercury and in which the amalgam
acts as an anode, may be constructed substantially similar to the electrolytic
apparatus described above with or without a systematic circulation of the liquids.
Dated this 28th day of March 1898.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent,
Improvements in and Apparatus for Effecting Electrolysis.
A communication from abroad by Messrs. SOLVAY & Co., of 25, Rue du Prince
Albert, Brussels, Belgium, Manufacturers.
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, in the County of London,
Consulting Engineer and Chartered Patent Agent, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement;-
This invention relates to improvements in and apparatus for effecting in a
continuous manner the electrolysis of alkaline chlorides and other salts in the
presence of a mercury cathode. The electrolytic process is rendered continuous
by causing the metal liberated by electrolysis to combine with mercury, treating
the amalgam so produced in another part of the apparatus for the purpose of
regenerating the mercury therefrom, and returning the regenerated mercury to
the electrolytic apparatus for re-use. Heretofore it has been necessary to cause
large quantities of mercury to circulate, and this circulation has been effected
by making the whole apparatus movable and imparting to it. a rocking motion,
or by constructing it with a slope and allowing the mercury to flow either along
the bottom or in spiral channels, or by displacing the mercury by means of

page_text: plungers or pistons; the circulation has also been effected by means of pumps.
These arrangements are such that if from any cause the movement of the mer-
cury be arrested, the apparatus will become destitute of mercury, although the
current continue to pass, so that more or less trouble will arise.
It has been observed that the alkaline amalgam forms especially at the surface
of the mercury, and tends to remain there by reason of its lightness.
Now according to this invention the surface of the mercury with the amalgam
is continuously removed so as to present continually a fresh surface to the metal
being liberated thereon, whilst the deeper lay of mercury remains more or less
at rest. For this purpose the electrolytic apparatus is, as illustrated in vertical
section and in horizontal section respectively in the accompanying Figs. 1 and 2,
so constructed that the surface 1 of the mercury will be perfectly horizontal,
and the layer of amalgam that is continually being formed when the apparatus
is in action will escape therefrom over a weir 2 arranged at one end. The pure
mercury is supplied at the opposite end, at a deep part 3, which forms a reservoir.
The improved apparatus thus contains no mechanical device whatever. It com-
prises a simple rectangular tank 4, which may be of any suitable length and
width, because there is nothing in the principle on which the invention is based
that limits the dimensions or that can interfere with the regular movement of
the layer of mercury. The bottom may be horizontal or not, but always remains
In order to empty
covered with mercury, even when the supply is arrested.
the trough completely for the purpose of cleaning it, the trough is inclined by
means of screw 5, or use is made of a cock (not shown) placed at the lowest point.
The mercury enters through a pipe 6 and passes out at the weir 2, which is
adjustable in height and which is intended to allow, more particularly, the
superficial layer (which is richest in alkaline metal) to pass off. The advantage
of this arrangement consists in that there is no restriction to a predetermined
discharge, as is the case with apparatus with inclined bottoms, and that the
output can be made such as is found to be the most advantageous, without
prejudicially affecting the efficient utilization of the electric current. Solid amal-
gam even might be produced floating on the surface of the mercury, as in this
apparatus its discharge does not present any difficulty, which is not the case with
apparatus heretofore employed.
With the object of promoting the circulation of this superficial layer, the
whole of the layer of liquid containing the salt in solution and situated above
the said superficial layer may be caused to circulate also in the same direction.
A liquid-elevator 7 is shown in Fig. 1 for raising the discharged mercury up
to the feeding level, but it is obvious that a pump or any other mechanical
device might be used equally well.
Apparatus for regenerating the mercury, in which the amalgam acts as an
anode may be constructed substantially similarly to the electrolytic apparatus
herein before described, with or without a systematic circulation of the liquids.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. A continuous-action apparatus for the electrolysis of alkaline chlorides or
other salts with a mercury cathode, in which the upper portion of the mercury
charged with alkaline metal passes off continuously over a weir arranged at one
end of the apparatus, and returns, after regeneration into the apparatus at its
lower part at the opposite end, whether the bottom of the vessel containing
the mercury is horizontal or not.
2. In apparatus according to the preceding claim, causing the superposed
liquid containing the salt in solution to flow in the same direction as the super-
ficial layer of mercury.
5 3. Electrolyzing-apparatus constructed, arranged, and operating as hereinbefore
described with reference to and shown in the accompanying drawings.

page_text: 4. Apparatus for regenerating the mercury from the amalgam produced in
the electrolysis of salts in the presence of a mercury cathode, constructed sub-
stantially similarly to the electrolytic apparatus hereinbefore described, with or
without a systematic circulation of the liquids.
Dated this 28th day of December 1898
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.