Improved Means applicable for use in the Extraction of Metals from Metallic Solutions.
Year: 1897

page_text: Date of Application, 15th Dec., 1897
Complete Specification Left, 13th Sept.. 1898 -Accepted 10th Cec.
1838
PROVISIONAL SPECIFICATION,
Improved Means applicable for use in the Extraction of Metals from
Metallic Solutions.
I, JOHN CUNINGHAME MONTGOMERIE, of Dalmore, in the County of Ayr,
Scotland, Justice of the Peace, do hereby declare the nature of this invention to
be as follows:
--
This invention relates to the extraction of metals from their solutions and to
apparatus applicable therefor; the objects of the invention being to secure
expedition, a high rate of efficiency and economy in the cost of working.
In treating liquids or solutions containing the precious or other metals, I
pass the liquid through a filter or through a series of filters containing a mixture
of wood charcoal or other carbonaceous or electro-negative metal or substance
and zinc or other electro-positive metal or substance, or a combination of electro-
positive metals or substances and electro-negative metals or substances.
A filter which gives highly satisfactory results. comprises a circular wooden
vessel provided with a false bottom covered with canvas filter-cloth. The wood
charcoal is reduced to a granulated condition, so as to be capable of passing
through a 1 inch mesh sieve, and, if found necessary in order to prevent the
sieve choking, the very fine dust may be removed. The zine is also granulated
and rendered capable of passing through a 20 inch mesh sieve. 80% of the
wood charcoal is taken and damped, and to this is added 20% of the granulated
zinc. The charcoal and zinc are thoroughly mixed together and placed in the
filter. The mixture is pressed therein to a thickness of 2 or 3 feet and made
fairly firm. On the top is spread a double thickness of cheesecloth, and over
this is fixed a perforated piece of wood, secured from floating by brackets screwed
to the side of the filter; or a little gravel may be thrown upon the top of the
cheesecloth. From the space between the false bottom and the bottom of the
filter vessel, lead pipes extend to the top of the filter vessel and serve to liberate
the, air confined beneath the. false bottom, as also the gases which may be
generated and carried down by the descending liquid, and which might otherwise
force their way to the surface through the layer of precipitating material. The
passage. of the liquid through the filter is regulated by a cock at the bottom of
the filter.
When the filter, ceases to deposit metal, such cessation taking place when the
zinc is nearly exhausted, the charcoal is burned and the metals recovered in the
usual way. Or the charcoal may be passed through an amalgamator and used
over again.
In extracting gold from sea-water, the filter may be constructed in the same
manner as before specified, but without gravel on the top, the size of the filter
being increased to hold a large quantity of water. The filter is so placed and
so regulated as to work automatically in the following manner. Assuming
for example a rise of tide of eight feet, the bottom of the filter is placed about
I foot from the lowest point reached by the outgoing tide. The filter is charged

page_text: with precipitating material to a depth of about 3 feet. A 4 feet space on the
top is filled by the incoming tide, the water filtering through the precipitating
material as the tide recedes. The bottom of the filter vessel is provided with a
non-return valve, so arranged as to prevent the incoming tide entering the
lower part of the filter but to open and permit the escape of the water upon the
tide receding.
By the herein described method of extracting metals from their solutions, a
more complete extraction is obtained than by using zinc or charcoal alone, and
the action is moreover accelerated by reason of the electrical action generated
by the mixture of precipitating agents.
An electric current may be used in this process, the current being passed
through the filtering material.
Improved Means applicable for use in the Extraction of Metals from
Metallic Solutions.
I, JOHN CUNINGHAME MONTGOMERIE, of Dalmore, Stair, in the County of Ayr,
Scotland, Justice of the Peace, 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 the extraction of metals from their solutions and to
apparatus applicable therefor; the objects of the invention being to secure
expedition, a high rate of efficiency and economy in the cost of working.
In the accompanying drawings, Fig. 1 is a vertical section of apparatus adapted
for effecting the objects of my invention. Fig. 2 is a horizontal section taken
on the line in Fig. 1; the wooden grid or perforated plate and the cheese-
cloth being removed.
In treating liquids or solutions containing the precious or other metals, 1
pass the liquid through a filter or through a series of filters containing a mixture
of wood-charcoal or other carbonaceous or electro-negative substance or metal,
and zinc or other electro-positive metal or substance, or a combination of electro-
positive metals or substances and electro-negative metals or substances.
A filter which gives highly satisfactory results is shewn in the accompanying
drawings and comprises a circular vessel A, which may be constructed of wood.
provided with a false bottom 3 covered with canvas filter-cloth C. The wood-
charcoal is reduced to a granulated condition, so as to be capable of passing
through a th inch mesh sieve, and, if found necessary, in order to prevent
the filter choking, the very fine dust may be removed. The zinc is also granulated
and rendered capable of passing through a th inch mesh sieve. 80 per cent. of
the wood-charcoal is taken and damped, and to this is added 20 per cent. of the
granulated zinc. The charcoal and the zinc are thoroughly mixed together and
placed in the filter upon the canvas filter-cloth C. The mixture is pressed into
the filter to a thickness of 2 or 3 feet, as shown at D, and made fairly firm. On
the top is spread a double thickness of cheese-cloth E; and over this is fixed
a perforated piece of wood F which may be secured from floating by brackets f

page_text: screwed to the side of the filter; or a little gravel may be thrown upon the top
of the cheese-cloth. From the space between the false bottom B and the bottom A¹
of the filter vessel, lead pipes G extend to the top of the filter vessel and serve
to liberate the air confined beneath the false bottom, as also the gases which
may be generated and carried down by the descending liquid, and which might
otherwise force their way to the surface through the layer of precipitating
material. These lead pipes may be provided with a flange g at their lower
extremity which rests upon the false bottom, the filter-cloths covering the flange.
The passage of the liquid through the filter is regulated by a cock H at the
bottom of the filter. I is a cover (indicated by dotted lines) which may be
applied to the filter when required.
When the filter ceases to deposit metal, such cessation taking place when the
zinc is nearly exhausted, the charcoal is burned and the metals recovered in
the usual way. Or the charcoal may be passed through an amalgamator and
after recovering from the charcoal as much of the metals as is possible, the
charcoal is reused.
In extracting gold from sea-water, the filter may be constructed as herein-
before specified, with the addition of a non-return valve; the size of the filter
being increased to hold a large quantity of water. The filter is so placed and
so regulated as to work automatically in the following manner: -Assuming,
for example, a rise of tide of 8 feet, the bottom of the filter is placed about one
foot from the lowest point reached by the out-going tide. The filter is charged
with precipitating material to a depth of about 3 feet. The space on the top,
which, in this instance, may be about 4 feet deep, is filled by the incoming tide,
the water filtering through the precipitating material as the tide recedes. The
vessel A is provided with a cock J in communication with the lower portion
of the filter, the pipe connection K being furnished with a non-return valve K¹.
The incoming tide is hereby prevented entering the lower part of the filter, but
upon the tide receding the pressure in the vessel causes the valve to open and
permits the escape of the filtered liquid. The outlet, of the non-return valve is
placed on a level with the top of the filtering medium so that the, water is not
allowed to drain out of it on the tide receding. The non-return valve and its
pipe connection may be placed inside the filter and embedded in the charcoal.
only the cock J being exposed. The cover I is provided with a number of
perforations to allow the water to enter the filter.
By the herein described method of extracting metals from their solutions, a
more complete extraction is obtained than by using zinc or charcoal alone, and
the action is moreover accelerated by reason of, the electrical action generated
by the mixture of precipitating agents.
An electric current may be used in this process, the current being passed
through the filtering material.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I claim :-
-
1. For use in the extraction of metals from metallic solutions by filtration, a
filtering medium consisting of a mixture of charcoal or electro-negative substance
with zinc or electro-positive substance, substantially as set forth.
2. The herein described method of treating metallic solutions for the extraction
of the precious or other metals, same consisting in passing the liquid through
a filter or through a series of filters containing a mixture of a carbonaceous or
an electro-negative substance, such as wood-charcoal, with an electro-positive
substance or metal, such as zinc, substantially as specified.
3. For employment in the extraction of metals from metallic solutions accord-
ing to the method herein referred to, a filtering medium prepared substantially
in the manner described and comprising a mixture of wood-charcoal and zinc
in granulated form, the zine being added to the charcoal after the latter has

page_text: been damped and both ingredients thoroughly mixed together, the mixture, being
thereupon pressed into the filter.
4. For employment in the extraction of metals from metallic solutions, a filter
constructed or operating substantially as described with reference to the accom-
panying drawings.
5. In a filter for treating metallic solutions, the employment, within the filter
casing of lead pipes for liberating the air or other gas from the space beneath
the false bottom, substantially as set forth.
6. In a filter for treating metallic solutions, the employment of a non-return
valve, such as K', substantially as and for the purposes specified.
7. In a filter for treating metallic solutions, the combination, with the
casing A, of the false bottom B, filter cloth C, filtering material 1), cheese-cloth.E,
perforated plate F; and regulating valve H or K, arranged or operating sub-
stantially as and for the purposes set forth.
Dated this 6th day of September 1898..
G. G. M: HARDINGHAM,
Chartered Patent Agent. 191, Fleet Street, London, E.C..