Separating and Purifying Metals.
Year: 1893

page_text: Date of Application, 4th May, 1893
Complete Specification Left, 3rd Mar.. 1894-Accepted, 4th June, 1894
PROVISIONAL DI BOLTIVATIO
Separating and Purifying Metals.
I, JONATHAN ALDOUS MAYS, of 1 Belsize Terrace, Hampstead in the County
my invention
of London, England, Gentleman, do hereby declare the nature of
to be as follows:-
My invention relates to separating metals from metals and purifying molten
metals by removing or eliminating other substances or materials therefrom.
For these purposes advantage is taken of the superior solvent property or
chemical affinity of some molten metals for others by using one such molten metal
as a menstruum or bath through which the mixed metals forming the subject
material is or are continuously passed and drawn off while in a molten state.
The molten metal forming the menstruum is sometimes of less specific gravity
than the molten subject material, and in such cases the latter is poured into and
flows or passes through the former.
While the subject metal or material is thus passing through the menstruum it
is deprived of the metal or constituent for which the menstruum has a superior
affinity or is a better solvent.
The menstruum may also be a metal of greater specific gravity than that of the
subject material, but in this case the latter must be forced into the menstruum at
a point beneath its surface-preferably at the bottom of the same.
Various molten metals may be caused to act as menstrua to each other by
concurrently passing heavy metals into the upper surface and forcing lighter
metals into the lower part of a bath.
In some cases instead of depending upon gravity as the means for producing
the flow of one molten metal through the other, I utilize centrifugal force for
producing such a flow in a direction approximately radial to the axis of revolution
of the machine or apparatus employed.
COMPLETE SPECIFICATION.
Separating and Purifying Metals.
I JONATHAN ALDOUS MAYS, of 1 Belsize Terrace, Hampstead in the County
of London, Gentleman, do hereby declare the nature of my invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:—
My invention relates to separating metals from metals and purifying molten
metals by removing or eliminating other substances or materials therefrom.
For these purposes advantage is taken of the superior solvent property or
chemical affinity of some molten metals for others by using one such molten metal
as a menstruum or bath, through which the mixed metals forming the subject
material is or are continuously passed and drawn off while in a molten state.
The molten metal forming the menstruum is sometimes of less specific gravity
than the molten subject material, and in such cases the latter is poured into and
flows or passes through the former.

page_text: While the subject metal or material is thus passing through the menstruum, it
is deprived of the metal or constituent for which the menstruum has a superior
affinity, or is a better solvent.
The menstruum may also be a metal of greater specific gravity than that of the
subject material, but in this case the latter must be forced into the menstruum at
a point beneath its surface, preferably at the bottom of the same.
Various molten metals may be caused to act as menstrua to each other by
concurrently passing heavy metals into the upper surface, and forcing lighter
metals into the lower part of a bath.
In some cases, instead of depending upon gravity as the means for producing
the flow of one molten metal through the other, I utilize centrifugal force for
producing such a flow in a direction approximately radial to the axis of revolution
of the machine or apparatus employed.
As my invention refers particularly to separating other metals from and
purifying molten lead I hereby disclaim any application of the same invention
other than that of separating or extracting metals from molten lead by the use of
a menstruum of molten zinc or alloy of zinc.
The foreign metals or impurities to be separated or extracted from argentiferous
or ordinary lead, generally speaking, are silver, gold, copper, antimony, and
arsenic, and I use the term "argentiferous" lead in this Specification as including
lead containing any or all of these metals.
For the purpose of removing any or all of these successfully according to my
invention it is necessary that the molten metal forming the menstruum shall
have a greater affinity for the impurities than the lead has. Zinc is peculiarly
suitable for use as such a menstruum but any alloy of zinc such as zinc and copper
or zinc and aluminium which has this greater affinity for the impurity in lead and
is also of a different specific gravity to lead may be used.
For the purpose of causing a molten metal or mixture of metals to flow through
another molten metal of a different specific gravity either or both of two natural
forces namely gravity and centrifugal force, may be utilised, and I therefore shew
apparatus suitable for use with either force. Whichever force is used in the
operation effects two purposes; first, it serves to carry the molten metal into and
through the zinc or other menstruum; and secondly, it effects the separation of the
Icad from the zinc. The first part of the operation leads to what may be regarded
as a chemical combination of the silver and other metals with the zinc. The second
part of the operation is purely of a mechanical nature.
In this Specification wherever I use the term "equivalent metal" I use the same
as meaning a metal having an equivalent property to zinc in respect to combining
with metals which may be contained or carried by argentiferous lead and which is
also of a different specific gravity to lead.
In the accompanying drawings in which like letters indicate similar parts, or parts
fulfilling the same functions:-
Fig. 1. is a plan; and
Fig. 2. is an elevation of a gravity apparatus.
Fig. 3. is a horizontal section, and
Fig. 4. is a vertical section of the same.
Fig. 5. is a plan, and
Fig. 6. is an elevation of a centrifugal apparatus.
Fig. 7. is a part horizontal section, and
Fig. 8. is a vertical section of same.
Fig. 9. is a vertical section through the axis.
Fig. 10. is a horizontal section on line 1, 1, and
Fig. 11. is a horizontal section on line 2, 2, of a modified form of a centrifugal
apparatus.
The standing parts are sectioned from top left to bottom right corners, while
the revoluble parts are sectioned from top right to bottom lett corners of the
drawings.

page_text: Referring to Figs. 1, 2, 3 and 4, K is the receiver or vessel for containing 'the
molten menstruum. It has the form of an inverted truncated cone, and at its lower
end is a siphon-shaped eduction tube M which is continued upwards to the height
required to secure a suitable depth of zinc in the vessel. The vessel K is surrounded
by a chamber or flue p through which either products of combustion from a burner P
or heated air from an outside source passes, for the purpose of maintaining a
suitable temperature around the vessel K. R is a chimney by which the heated
air or products of combustion escape into the atmosphere. The inside surface of
an outside casing D is lined with a non-conducting material I for the purpose of
retaining the heat. The argentiferous lead is poured into the funnel L and passes
by the tube to the annular channel and longitudinal channels o in the grid O
whence it overflows in extremely thin films into the body of zinc forming the
menstruum. The lead is thus subjected to the action of the zinc under such
favourable conditions as to secure the intimate contact of each and every particle
with the surrounding menstruum. The greater specific gravity of the lead as
compared with that of the zinc causes it to pass completely through the whole
depth of the menstruum and finally it flows off continuously by the siphon-shaped
eduction tube M into any convenient receptacle. k is a casing which forms part of
the same casting as the cover d' and annular channel 1, and k¹ is a cover for
the vessel containing the menstruum. dare trunnions for use in turning the bath
over.
In some cases I secure a continuous replacing of the menstruum by causing zinc
to pass in at a point near the bottom of the vessel, whence, gradually flowing upwards
it escapes near the top of the same.
The zinc supply pipe Z and zinc eduction pipe N for use in such cases are shewn
in dotted lines.
Figs. 5 and 6 shew outside views of part of the fixed casing and of the revoluble
parts of a centrifugal apparatus for the purposes of my invention.
A is a base plate between which and the plate a is interposed some resilient
material for neutralizing the vibration of the rotating parts. A projection a' in the
centre of this latter plate a forms a foot-step bearing for the spindle B upon and
with which all the revoluble parts rotate. C is a bow shaped bracket the centre
boss c of which forms the upper bearing for the spindle B for which bearing b² is
an oiling device. b is a pulley and a belt for rotating the spindle B. Rigidly
attached to the upper end of this spindle B is a boss which forms part of the outer
casing H of the rotating vessel, which outer casing being continued upward in the
form of an annular wall meets and has fixed to it the cover h. K is the interior
receiver or vessel in which is contained the molten zinc or other menstruum, and
between this and the outer casing H is interposed a layer of non conducting
material for the purpose of preventing the beat of the receiver being communicated
to the outside casing H. O is a cylindrical chamber having a number of small
perforations o through which the argentiferous lead passes into the zinc menstruum.
The argentiferous lead is supplied through the funnel L and pipe to the annular
gallery T whence it flows through the orifices t into the cylindrical chamber O
and thence through the menstruum. The passing of the lead through the
menstruum removes the impurities hitherto contained in it and finally the purified
lead flows off continuously through the eduction tube M into the lead collector F
which is emptied by the pipe f. f is a deflecting plate. U is a funnel and u a
pipe whereby molten zinc, or its equivalent metal is supplied to the distributor z
and by centrifugal force passes through the tubes 2' to the perforated tube % whence
it flows into the molten menstruum.
The addition of more zinc to a menstruum which may be supposed to reach
already to the level determined by the outflow tubes N causes some of the
menstruum to escape through them, strike against the zinc deflector 9 and fall
into the fixed zinc-alloy collector G. Thus argentiferous lead is continuously flowing.
in and passing out in a purified state into one collector while fresh zinc is slowly
passing in and flowing out as zinc-alloy into another collector.

page_text: Figs. 9, 10 and 11 shew a machine with some slight modifications in detail where
it is intended to discharge only the lead continuously through the eduction tube M
the body of zinc forming the menstruum remaining in the vessel until it has become
sufficiently enriched, when, the supply of argentiferous lead being discontinued, and
the rotation of the machine stopped, the whole charge passes under the diaphragm n
and escapes through the eduction pipes N. m is a diaphragm which is placed so as
to secure the discharge of that portion of the purified lead which is situate near the
extreme radius of the vessel K. It will be seen that the gallery T is somewhat
differently shaped from that shewn in Fig. 8 and that an annular tapering wall t is
introduced for the purpose of sealing the zinc forming the menstruum from the
atmosphere. The argentiferous lead fills part of the gallery and passes through
the orifices into the channels o of the grill O and flows over the edges of these
channels into the molten zinc forming the menstruum. The channels (shewn in
horizontal section in Fig. 11.) serve the same purpose as the perforations o in
Fig. 8, of securing the distribution of the molten argentiferous lead in minute
particles, thin films or filaments in the menstruum thus securing intimate contact of
the subject metal therewith. dis a bracket for supporting the lead pipe l.
In these figures is also shewn a method of heating the receiver or vessel as well
as the collector. p₁ is a pipe through which is supplied either gas, gas and air, or
heated air. P is a burner of any suitable kind either common o atmospheric. The
heated products of combustion from this burner pass through the grooves or
channels P which form flues around the outside of the vessel K and thereby
maintain the required temperature of the menstruum. The products of combustion
then pass on into a flue or chimney R (formed by two plates which rotate with
the vessel), and are caused to impinge upon and heat the lead collector F. They
then pass through the fluer into the atmosphere. When air heated outside the
apparatus is employed the burner P is not used but a supply of hot air is forced
through the device shewn in dotted lines into the flues p and this follows the same
course as the products of combustion above referred to.
The centrifugal machines here shewn have their axes of rotation vertical, but
they may be made in such manner that their axes of rotation are either horizontal
or inclined at any angle.
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. The process hereinbefore described of continuously separating metals from
and purifying argentiferous or impure molten lead which consists in passing the
same impure molten lead in minute particles through a molten menstruum of zinc or
alloy of zinc in such manner as that the menstruum combines with and retains the
silver or other metals while the lead itself passes through the menstruum and flows
off continuously.
2. The apparatus for separating other metals from argentiferous lead by the
force of gravity and shewn in Figures 3 and 4 of the drawings consisting essentially
of a receiver or vessel for containing the molten zinc or other menstruum, a feeding
device for supplying the argentiferous lead in minute particles to the menstruum,
and an eduction passage, or passages, substantially as described.
3. The centrifugal apparatus for separating other metals from argentiferous lead
consisting essentially of a revoluble receiver or vessel for containing the molten
zine or other menstruum, means for rotating the same, a feeding device for
supplying the argentiferous lead in minute particles to the menstruum, and an
eduction passage or passages through which the purified lead passes out substantially
as described.
4. The centrifugal apparatus for separating other metals from argentiferous lead
consisting essentially of a revoluble receiver or vessel for containing the molten zinc
or other menstruum, means for rotating the same, a feeding device for supplying
the argentiferous lead in minute particles to the menstruum, an eduction passage or

page_text: passages through which the purified lead passes out a supplying device for the
molten zinc or other menstruum, and an eduction passage or passages for the same,.
substantially as described.
5. The centrifugal apparatus for separating other metals from argentiferous lead
consisting essentially of a revoluble receiver or vessel for containing the molten
zinc or other menstruum, means for rotating the same, a feeding device for
supplying the argentiferous lead in minute particles to the menstruum, an eduction
passage or passages through which the purified lead passes out and a stationary
collector for receiving and holding the purified lead, substantially as described.
6. The centrifugal apparatus for separating other metals from argentiferous, lead
consisting essentially of a revoluble receiver or vessel for containing the molten
zinc or other menstruum, means for rotating the same, a feeding device for
supplying the argentiferous lead in minute particles to the menstruum, an eduction
passage or passages through which the purified lead passes out a supplying device
for the molten zinc or other menstruum, an eduction passage or passages for the
same, and stationary collectors for receiving and holding the purified lead and the
zinc-alloy respectively, substantially as described.
7. In a centrifugal apparatus for separating other metals from argentiferous lead,.
the means for heating the revoluble containing vessel or receiver and the stationary
collectors, substantially as described.
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