Improvements in or relating to the Electrolysis of Liquids and Apparatus therefor.
Year: 1898

page_text: [Communicated from abroad by MAURICE HAZARD-FLAMAND, of Boulogne-sui-
Semme, in the Republic of France, Electrical Engineer.]
Improvements in or relating to the Electrolysis of Liquids and
Apparatus therefor.
I, WILLIAM PHILLIPS THOMPSON, FCS, MIME, of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord Street,
Liverpool, and 6, Bank Street, Manchester, both in the County of Lancaster,
and Lower Temple Street, Bumingham, in the County of Warwick, Chil
Engineer, do hereby declare the nature of this invention to be as follows.
This invention relates especially to improvements in the separating of the
eler tiodes, and has for one object to provide a new system of diaphragms which
will not often obstacles on resistance to the passage of the electric curents, not
prevent the decomposing action which the electric cunent is intended to have upon
the electrolyte, whilst at the same time preventing the gases liberated at the
positive electrode from mixing with the gases liberated at the negative electiode,
even when there occur differences of pressure and of level in the cells formed by
the said separating diaphragms.
The diaphragms herein before employed for this purpose do not fulfil in so perfect
a manner the required object, either because they offer too much reaistance to
the passage of the electic curent, or because they can be penetrated by the gases
Jiberated at the electrodes, o again because being formed by materials which are
conductors of electricity, they can give rise under certain conditions to the formia-
tion of intermediary poles, upon which there takes place a liberation of gas,
and in consequence whereof there results an intermixture of the gases liberated
at the positive pole, and at the negative pole, which is precisely what it is desued
to avoid.
The negative electrode is formed preferably by a vessel of suitable material,
wluch conducts electricity, the vertical internal walls whereof air covered with
bs for the purpose of increasing the surfaces and of conespondingly diminishing
the polarisation The interior of the vessel is divided into equal compartments,
The said pai-
by means of divisions cast in metal in one piece with the vessel
titions are likewise covered with libs
Upon the whole of its exterior surface the vessel is provided with a deep channel
o gutter in which lodges the 1m of the covei, and this gutter is filled with an
Insulating liquid to form the hydraulic joint. The cover iests upon the edges of
The vessel moreover, has
the vessel by means of interposed pieces of ebonite
a screw terminal upon which is attached the conducting wire for the curent m
the usual manner.
The positive electrode is formed of suitably formed and placed blades of cast
1on, or other suitable conducting material, insulated by rings of ebonite; the
Insulated conductor is enclosed in a suitable container, itself sunlounded by
cylinder with a hydraulic oil seal which will prevent any escape of gas
This

page_text: insulation as well as the obstacle to the escapes of gas can be constructed in any
other desired manner
The different cells for each pole are arranged in the following manner,
The positive electrodes are surrounded with lengthened rings of insulating
material impermeable to gases and superposed so as to form in the interior and
around each positive electrode a vertical tube.
Each ing forming a hydraulic joint with the following ring and the pieceding
ing has such a section that it will guide perfectly the vertical ascent of the gases
and will absolutely prevent the mixture of the gases which are liberated at the
electrodes which are separated by the said superposed 11ngs Morcover, these rings
when super posed, form hydraulic joints one with the other, whilst the liquid seals
of the hydraulic joints will freely allow the electric curient to pass This 18 best
attained by giving them a Y form so that the rings form hydraulic joints sealed
by the liquid whilst freely allowing the passage of the electic curient
native modes of producing the like result may however be adopted
Altei-
The electrolyte, may be a conducting solution of an alkali such as soda or
potash The carbonating of a caustic liquid 18 prevented by a layer of mineral
oil. The gases disengaged at the electrodes are collected in the following
manner.-
The lid of the vessel has two channels of cast on, the longitudinal axis of
which 18 normal to the surface of the electrodes The channel devised to collect
the gases disengaged in the positive cells communicates with the said positive
cells, and the channel devised to collect the gases liberated in the negative cells,
communicates with these latter cells To each of these channels are attached
collecting vessels
If the liquid is allowed to run short though negligence and the level of the
liquid in the vessel is reduced down to the lower lip of the cast on ring which
foims the hydraulic joint, the gas escapes around this ring and passes through
the hole escaping to the outaide through the liquid Joint The bubbling which
results in the upper cells formed upon the lid, notifies this accident, and without
allowing the gases, which thus find a way of escape towards the outside to become
mixed, that is to say, to pass from a positive cell to a negative one
In the caso
where the disengagement of the gases of one or more cells 18 prevented by an
obstruction of any kind the pressure which results causes the level of the liquid
to sink in the coresponding cells, but this level when it reaches the lower part of
the lip of the 1m of the cover, escapes to the outside as before, producing n
bubbling which indicates the accident without danger of any mixture as already
explained in the preceding case
This system of separation 18 especially designed for apparatus producing oxygen
and hydiogen by the decomposition of water by the passage of an electric current,
but the same system 18 applicable for the production by electrolysis of any kind
of gas

page_text: Liverpool, and 6, Bank Street, Manchester, both in the County of Lancastui,
and Lower Temple Street, Birmingham, in the County of Warwick, Civil
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly descubed and ascertained in and by the
following statement.-
1
Thus invention relates to a device for obtaining gases by electrolysis free from
admixture, the said gases being so separated from the moment of then production
onwards, that no gas disengaged from the one electrode can possibly become mixed
with that from the other, even if difterences of level and of pressure occur in the
apparatus.
The invention will be described in view of the production of oxygen and of
hydhogen by the decomposition of water by electricity, but it is equally applicable
to the production of other gases which can be obtained by the action of an electric
current.
Refening to the accompanying diawings,
Fig is an elevation of the apparatus, partly in longitudinal section, partly
in elevation
Fig 2 is a horizontal partial section of the apparatus on the line X, X of Fig 1
Fig is a horizontal section of the apparatus on the line Y-1 of Fig.
Fig 4 is a vertical section of the apparatus partly on the line 7---% of Fig 2,
and partly on the line V-V thereof, looking in the direction of the aurow
The negative electrode is formed by a vessel A of cast iron or other suitable con-
ducting material, the vertical internal walls whereof are covered with tbs for
the purpose of increasing the surfaces and of corespondingly diminishing the
polarization. The interior of the vessel A is divided into equal compartments, by
means of divisions a' cast in metal in one piece with the vessel The said partitions air
likewise provided with ribs a² The vessel A can be constructed of insulating
material, but in this case negative electrodes formed of suitable plates must be
provided and connected together by a suitable conductor
Around the whole of its exterior surface the vessel A is provided with a deep
channel or gutter B in which lodges the rim of the cover M, and this gutter is
filled with an insulating liquid to form an hydraulic joint The cover Mests
upon the edges of the vessel by means of interposed pieces of ebonite B The
vessel moieover, has a screw terminal 1) upon which is attached the conductor for
the current in the usual manner
The positive electrode is formed of plates E of cast iron, or other suitable con-
ducting material having ubs e placed within the compartments of the vessel A,
and supported by the conducting bais el which pass through the hd of the vessel,
being electically insulated from this latter by ings of ebonite to prevent any
escape of gas. The conducting bar el 18 enclosed in a bell with a paraffin joint,
and this bell is itself enclosed in a evludical vessel m² cast in one piece with the
lid M. This cylindrical piece m² is filled with paraffin oil constituting an
hydraulic joint, which will prevent any escape of gas
All the conducting bais aie connected with a conductor F which leads to the
screw terminals of the following vessel
The electrodes are separated by diaphagus so constructed as to prevent anv
admixture of the gas evolved by the opposite poles of each pan, whilst allowing
free passage to the electric current, the diaphragms shewn are of the siphon type.
but any construction having the property of efficiently separating the gases and
giving passage to the current may be employed I make no clan for the precise
construction shewn by way of example
The positive plates E are surrounded with elongated gas proof insulating rings H
(ebonite, porcelain, glass, enamelled iron, and so forth) superposed so as to form
internally a vertical tube around the positive electrodes E
Each ring forms an hydraulic joint with the following and the preceding ung,
and has the section shewn in Fig. 1, so that whilst the elective curent can pass

page_text: freely though the liquid in the cups, escape of the gases through the rings is
absolutely prevented The form shewn in Fig 1 is pietened to any other, because
it gives the largest sectional area to the liquid conductor
The aforesaid ings H are maintained the one above the other by means of the
external supporting pieces (Fig. 4) secured to the ends of the said ung-
h
Below
they are supported by the pieces upon a porcelain dish I or other suitable insulat-
ing material which is impermeable to the gases. This dish I (Figs 1 and 4) only
iests upon its feet, and the centre has underneath a hollow I devised to allow the
free passage to the hydrogen gas which may be generated below the bottom of
the dish (see Fig 1).
In order to close the upper part of the cell containing the positive electrode, the
last ng His preferably of the shape shewn and ends in a deep channel in
which the cover M forms an hydraulic joint by the aid of the prolonged rings m
cast in one piece with it One or more holes 3 suitably placed, pierced in the last
Insulating ing put the liquid of the vessel into hydraulic communication with
the liquid contained in the reservou formed in the upper part of the cover by means
of the lips or walls m¹ The reason for this aangement will be explained here-
after.
ما
The electrolyte, that is to say, the solution which is decomposed by the cuent
into hydrogen and oxygen is preferably a conducting solution of an alkali such
as soda or potash The carbonating of the liquid is prevented by a layer of mineral
oil, which is placed into the reservous formed at the upper part of the cover by
the bs m. The holes 3 pierced in the last ng being upon an equi-potential
line, there could theoretically only be produced parasitic currents in the lid
practice the place for these holes cannot be fixed mathematically, and curients
of very small intensity are produced, but they are absolutely unimportant, because
the electiomotive force, being proportional to the distance between the holes and
then themetical position, is insignificant, because from one plate to the other this
electiomotive force cannot exceed thee volts. Further, the resistance is enormous,
because the holes are of small diameter, and of very limited number
In practice there can be obtained the theoretical quantity of gas corresponding
to the quantity of the current which traverses the volt-meter. Moreover, the
electromotive force of these parasitic curients being only a small fraction of a
volt, cannot decompose the electrolyte and give admixture of gas
The gases
disengaged at the electrodes and being so placed that they cannot mix as alieady
explained, are collected in the following manner.―
The lid M of the vessel has two channels of cast iron, one of which N is shewn
at the left of the axis of the vessel Figure 5 and the other N is placed symmeti-
cally therewith, e to the night of the axis of the vessel the longitudinal axıs
of these chaunels are normal to the surface of the electiodes The left channel N.
for instance, devised to collect the gases disengaged in the positive cells com-
municates by the holes with the said positive cells, whilst the night channel N
devised to collect the guses liberated in the negative cells communicates through
similar holes with the negative cells
These channels communicate with collect-
ing vessels (not shown in the drawing) thereof one collects the oxygen and the
other the hydingen. It has been already said that the reservons formed by the 11bs m
are upon the lid and contain liquid in communication with the liquid m the
interior of the vessel, this aangement has for its object to form an hydraulie
Joint which prevents the gases from escaping to the open an through the holes h²
and m when the apparatus is working normally
If, however, the liquid is allowed to run short through negligence and the level
of the liquid in the vessel 18 reduced down to the lower lip of the cast non ring m
(Figure 1) which forms the hydraulic joint, the gas escapes around this 11ng and
passes through the hole m escaping to the outside through the liquid Joint The
bubbling which results in the upper cells formed upon the lid, notifies this accident,
and without allowing the gases, which have found a way of escape towards the

page_text: outside to become mixed, that is to say, to pass from an internal cell to the other
If the disengagement of the gases of one or more cells 18 prevented by an obsti uc-
tion of any kind to the holes no the pressure which results causes the level
of the liquid to sink in the corresponding cells, but this level when it reaches the
lower pait of the hip of cast non of the m m of the cover, escapes to the outside
as before, producing a bubbling which notifies the accident without danger of any
mixture as aheady explained in the pieceding case.
My system of separation is especially designed for apparatus producing oxygen
and hydrogen by the decomposition of water by the passage of an electric curent.
but I may apply the same system for the production by electrolysis of other gases
Having now particularly described and ascertained the natane of my said
invention, and in what manner the same is to be performed, I declare that what
I claim 18:
1) In apparatus for the electrolysis of liquids, the combination with positive
and negative electrodes of an annular gas-tight diaphragm having liquid-sealed
apertures separating the said electrodes, a gas-tight cover enclosing the electrodes.
e deep inner im on said cover dipping in a channel around the outside of the
electrolytic cell, a reseivou on said cover surrounding the positive electrode tei-
minal normally sealed by liquid but communicating with the interior of the cell
though a small aperture in a downwardly prolonged and liquid-sealed annulai
projection placed over the top of the diaphragm in such a manner that any gas
forcing the liquid seal of the said diaphragm will escape through the aforesaid
projection without mingling with the gas from the negative electrode, substan-
tally as descubed
2) In apparatus for the electrolysis of liquids the combination with a gas-
tight annular diaphragm such as H of the covei M having above the receptacle m
and beneath an annulai prolongation communicating with m' and affording exit
by means of a hole m to any gases entering the diaphragm and using therein
through the tube h of the uppermost ning H¹ of the said diaphɩagm, substan-
tially as and for the purpose described.
3) The improved apparatus for the electrolysis of liquids constructed and operat-
ing substantially as described, with reference to the accompanving drawings
W P. THOMPSON & Co,
322, High Holborn, London, WC, Patent Agents for the Applicant