Improvements in Electrolytic Apparatus.
Year: 1893

page_text: Date of Application, 22nd Apr., 1893
Complete Specification Left. 5th Aug., 1893-Accepted, 11th Nov., 1893
PROVISIONAL SPECIFICATION.
Improvements in Electrolytic Apparatus.
CORNELIUS HANBURY of Three Colts Lane Bethnal Green Junction in the
County of London Manufacturing Chemist do hereby declare the nature of this
invention to be as follows :—
This invention relates to improvements in the construction of electrolytic tanks
and arrangements whereby the electrolyte is made to circulate and is otherwise
dealt with without interference with the electrolytic operation.
I construct a tank of slate or other convenient material. It is oblong or square.
Near the opposite ends or sides partitions are fixed cutting off two narrow portions
which I will call the transverse chambers. Each of these transverse chambers is
divided in two, an upper and a lower, by a horizontal partition fixed and made
water tight at about one third from the bottom. Between these transverse
chambers at the opposite ends or sides of the tank and at right angles to them
porous diaphragms each with an anode and cathode are fixed, so as to form water-
tight compartments which contain alternately, except in the first and last, two
positive and two negative electrodes. In the space corresponding to every other
compartment, a free aperture is made near the top of the partition into the upper
transverse chamber at one end or side of the tank, the lower edge of which aperture
dips just below the intended level of the electrolyte, and the partition at the other
end or side is similarly perforated with free apertures near the top in the spaces
corresponding to the other alternate compartments. At the bottom of each
transverse partition free openings are made between alternate compartments and
the lower transverse chamber, the openings in this lower series alternating with the
openings in the upper series. The whole tank is shut in by a closely fitting cover
which for convenience may be divided into sections corresponding to the transverse
chambers and the positive and negative compartments or otherwise. At one end
of each of the upper transverse chambers and above the highest intended level of
the electrolyte, an opening is provided through which the gas evolved is drawn off.
To each upper transverse chamber a pump is attached which forces the electrolyte
through a pipe passing to the lower transverse chamber at the other end or side of
the tank.
A similar result may be obtained by not subdividing the transverse chambers into
upper and lower by horizontal partitious but substituting for the lower transverse
chambers pipes continued from the pumps and opening into the positive and
negative compartments respectively.
In the interval between the pump and the lower transverse chamber, or
equivalent pipes, to which it drives the electrolyte, the liquid may be cooled or
warmed by passing through a condensing worm or equivalent apparatus, and, if
chloride of sodium or other soluble material is the electrolyte, the solution may be
continually strengthened by causing the liquid to pass through a vessel in which is
placed a perforated receptacle containing a supply of the material required to
strengthen the solution. Such vessel may be placed in a tank and surrounded by
iced, cold, or warm water as required.
In order to maintain uniformity of level in all parts of the tank and to supply
fresh fluid as that in the tank is drawn off, a "feed" cistern in which the electrolyte
is automatically kept at the required level communicates by a pipe with each of the
upper transverse chambers entering, preferably near the outlet to the pump. The
transverse chambers are each provided with outlet cocks for drawing off their
contents.

page_text: Taking as an example the electrolysis of chloride of sodium and starting with
the abovedescribed electrolyser empty, it will be seen that the solution passing
from the feeding tank flows by one pipe into the upper positive transverse chamber,
fills it, and thence overflows into the positive compartments having reached the
intended level connection is made with the source of electricity, the pump is set in
action and the solution is drawn from the upper positive transverse chamber and
forced through the pipes and through the vessel in which it may be strengthened
with fresh ealt and evoted into the lower positive transverse chamber and thence
into the positive compartments again, at the bottom and at the opposite end to that
at which it again overflows into the upper positive transverse chamber, thence to
repeat the same circuit.
Above the whole surface of the electrolyte in the positive electrolytic compart-
ments and the upper transverse chamber with which they communicate chlorine
accumulates and is drawn off near the end of the upper positive transverse
chamber.
In the negative system the movements are identical. Hydrogen being liberated
from the surface of the electrolyte in the negative compartments and drawn off
through an opening near the end of the upper negative transverse chamber, and
solution of soda by a tap at its bottom.
Dated this 22nd April 1893
ERNEST SALAMAN,
61 & 62, Chancery Lane, London, Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Electrolytic Apparatus.
CORNELIUS HANBURY of Three Colts Lane Bethnal Green Junction in the
County of London Manufacturing Chemist 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 improvements in the construction of electrolytic tanks.
Reference being made to the accompanying drawings.
Now according to my invention I construct a tank of slate or other suitable
material Fig. 1. A. preferably oblong or square. Near two opposite ends or sides
partitions B B are fixed cutting off two narrow portions which I will call the
transverse chambers C. C. Each of these transverse chambers is divided into two,
an upper C, and a lower C', by a horizontal partition D fixed and made watertight
at about one-third from the bottom. Between the partitions forming these
transverse chambers and at right angles to them porous diaphragms E. E. E. are
fixed so as to form compartments which contain alternately positive and negative
electrodes. In the space corresponding to every other compartment an aperture F
is made near the top of each partition B B into the upper transverse chamber at
one extremity of the tank, the lower edge of which aperture dips just below the
intended level of the electrolyte, and the partition at the other extremity is
similarly perforated with free apertures F1 F1 near the top in the spaces corre-
sponding to the other alternate compartments. At the bottom of each transverse
partition free apertures G G G are made between alternate compartments and the
lower transverse chamber, the openings in this lower series alternating with the
openings in the upper series, and if the tank is long their size may be gradually
enlarged from the point where the fluid enters so as the better to equalise its
distribution. Small holes g & g are made above the first and last of these openings,
close to the top of each of the lower transverse chambers to allow, when the tank
is being filled, of the escape of the air from these lower chambers. The whole
tank is shut in by a closely fitting cover which for convenience may be divided into

page_text: sections H H H Fig. 2 corresponding to the transverse chambers and the positive
and negative compartments or otherwise. At one end or at any other convenient
part of each of the upper transverse chambers in the top or above the highest.
intended level of the electrolyte, openings fitted with pipes I I¹ are provided
through which the gas evolved is drawn off. To each upper transverse chamber a
pump P P Fig. 4 is attached which draws the electrolyte from it and forces 1
through a pipe to the lower transverse chamber at the other end or side of the
tank. If the tank is long or if more than one are put in communication, this pipe
is made to reenter at the opposite extremity to that from which it leaves the tank
or series of tanks in order the better to equalize the circulation. A similar result
may be obtained by not subdividing the transverse chambers into upper and lower
by horizontal partitions but substituting for the lower transverse chambers pipes
continued from the pumps and openings into each of the positive and negative
compartments respectively see Fig. 9. In the interval between the upper transverse
chambers and the pump, or between the pump and the lower transverse chamber or
equivalent pipes to which it drives the electrolyte, the liquid may be cooled or
warmed by passing the pipe containing it through a trough or case Fig. 4 J & J¹
supplied with water and, if solution of chloride of sodium or of other solid material
is the electrolyte, the solution may be continually strengthened by causing the
liquid to pass through vessels K & K Fig. 4 in each of which is placed a perforated
receptacle containing a supply of the material required. Such a vessel may be
placed in a tank and surrounded by water which may be cooled or warmed as
required. If a solution of chloride of sodium is the electrolyte, in the positive
system a large shaped earthenware pipe may be interposed in the line of pipes
the branch projecting upwards and if necessary a second pipe may be connected to
this so as to come up to the top of the tank L K Fig. 4 the said perforated
receptacle being placed in the vertical portion of the said earthenware pipe. If
the electrolyte is a liquid it may be allowed to flow into such vessels at the rate
found most desirable.
In order to maintain uniformity of level in all parts of the tank and to supply
fresh fluid as that in the tank is drawn off I provide a "feed" cistern M Fig. 4 in
which a supply of the electrolyte is automatically kept at the required level
communicating by means of pipes N & N¹ Fig. 4 with each of the upper transverse
chambers entering, preferably, near the outlet to the pump, or they may enter the
positive and negative system at any convenient part of the apparatus. The trans-
verse chambers are each provided with suitable outlet cocks O O¹ for drawing off
their contents also cocks at or close to the bottoms thereof for washing out, not
shown in the drawings.
To prevent the pumps or other apparatus employed to draw off the gases from
sucking solution into the tank and so raising its level above the required point, I
insert a syphon tube or tubes or snifting valves for the admission of air where most
convenient.
Taking as an example the electrolysis of chloride of sodium and starting with
the above described electrolyser empty, it will be seen that, in the arrangement
above described, the solution passing from the feeding tank flows by one pipe into
the upper positive transverse chamber and by the other into the upper negative
transverse chamber, fills them and thence overflows into the positive and negative
compartments respectively, filling at the same time the lower transverse chambers.
In the drawing Fig. 4, these pipes N N₁ are shown as joining the vessels leading
to the lower chambers. The solution having reached the intended level, the
electrodes are put in connection with the source of electricity, the pumps are set
in action and the solution is drawn from the upper transverse chambers and forced
through the pipes and vessels in which it may be strengthened with fresh salt and
cooled, into the lower transverse chambers and thence again into the positive and
negative compartments respectively, at the bottom and at the opposite end to that
at which it again overflows into the upper transverse chambers thence to repeat
the same circuit. Above the whole surface of the electrolyte in the positive

page_text: electrolytic compartments and the upper transverse chamber with which they
communicate, chlorine accumulates and is drawn off near the end of the upper
positive transverse chamber, or from any other convenient spot.
In the negative
system hydrogen accumulates over the surface of the electrolyte in the negative
compartments and is drawn off through an opening near the end of the upper
negative transverse chamber, or at any other convenient spot, and the solution of
caustic soda by a tap or valve at its bottom. When two or more tanks are to be
put into communication with each other it may be conveniently effected by placing
them end to end and making communication between the transverse chambers by
suitable pipes or by closed channels constructed of slate as shown at R R R Fig 3.
For large installations requiring numerous tanks the following arrangement is
preferable The tanks are placed side by side each one being a few inches below
the one preceding it, as shewn in Fig. 5. Pumps P P¹ drive the electrolyte of the
anode and cathode compartments respectively from the lowermost to the uppermost
tank which it enters at the end of the lower positive and negative chamber respectively.
Thence it rises through the respective compartments and overflows into the upper
positive and negative transverse chambers whence suitable pipes convey it to the
respective lower transverse chambers of the second tank where it rises through the com-
partments and again overflows into the upper transverse chambers whence it is again
conveyed to the lower chambers of the next tank and so on through as many tanks
as desired Fig. 5. The draw-off pipes S Fig. 8. within the upper transverse
chambers are turned up and adjusted so that their upper orifice is exactly at the
level the electrolyte is desired to retain. Thus arranged they can only draw off
the excess as it flows in from the pumps or feed cistern, and care must be taken
when admitting fresh fluid from the cistern to draw off from the lowest tank at
the same rate. If a sufficient number of tanks are employed to produce the
maximum decomposition obtainable or which is most economical no pumps will be
required as the liquid products will be drawn from the lowest tank finished, as to
their electrolysis, whilst from the feed cistern M Fig. 5, fresh electrolyte will be
supplied to the first tank at the rate at which it is to flow or be drawn off from the
lowest. If pumps are used the pipes conveying the returning fluid may be
surrounded with water and vessels for strengthening the solution as above described
may be interposed near the first tank or where convenient. Or any or all of the
pipes from the upper transverse chambers may be brought down any convenient
distance below the bottom of the tank and surrounded by water before entering
the lower chamber of the next tank see Fig. 6. the pipes X. X. X. passing through
a tank or vessel not shewn. To equalise the circulation it is well to carry the
connecting pipes diagonally under each tank to enter the next at the opposite end
to that at which it left the preceding tank, and to that from which it will again
flow out as shown in plan Fig. 7.
At any convenient position the arrangement for strengthening the electrolyte
may be introduced. The gases are collected and drawn off by tubes Fig. 5 V & V'
connected respectively with all the positive and all the negative upper transverse
chambers by means of their outlet tubes I & I¹ Fig. 5.
The pipes conveying the contents of the anode compartments must be of suitable
material such as well-glazed earthenware or ebonite. Those connected with the
cathode compartments must also be of suitable material.
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 a tank or vessel for electrolysis divided into anode and cathode compart-
ments, the use of transverse channels or chambers crossing each end of such anode
or cathode compartments substantially as herein before described and for the
purpose stated.
2. In a tank or vessel for electrolysis divided into anode and cathode compart-
ments the combination of an upper transverse chamber communicating with one

page_text: end of the anode compartment, with a lower transverse chamber at the opposite
end of the vessel communicating with the other end of the same compartments.
3. In a tank or vessel for electrolysis divided into anode and cathode compart-
ments the combination of an upper transverse chamber communicating with one
end of the cathode compartments with a lower transverse chamber at the opposite
end of the vessel communicating with the other end of the same compartments.
4. In a tank or vessel for electrolysis divided into anode and cathode compart-
ments, the use of transverse channels or chambers crossing each end of such anode
or cathode compartments in combination with the pipe or pipes communicating
with each of the positive and negative compartments respectively substantially
as described with reference to Figure 9. of the accompanying drawings.
5. The construction of electrolytic apparatus substantially as hereinbefore
described and illustrated by the accompanying drawings.
Dated this 5th do of Ano 1902
ERNEST SALAMAN,
Pinner's Hall, Great Winchester Street, E.C., Agent for Applicant.