A NEW METHOD OF TREATING COPPER, LEAD, AND ZINC ORES, THE CINDERS OF WORKERS IN THE PRECIOUS METALS, THE RESIDUE FROM RETORTS OF ZINC FURNACES, THE SCHLAMS, THE ZINCIFEROUS AND ARGENTIFEROUS FUMES, AND FOR THE EXTRACTION OF SILVER FROM COPPER AND LEAD ORES
Year: 1879

page_text: LETTERS PATENT to Alfred Lambotte-Doucet, of 39, Rue Royale, Brussels, in
the Kingdom of Belgium, for the Invention of "A NEW METHOD OF TREATING
COPPER, LEAD, AND ZINC ORES, THE CINDERS OF WORKERS IN THE PRECIOUS
METALS, THE RESIDUE FROM RETORTS OF ZINC FURNACES, THE SCHLAMS, THE
ZINCIFEROUS AND ARGENTIFEROUS FUMES, AND FOR THE EXTRACTION OF
SILVER FROM COPPER AND LEAD ORES."
Sealed the 16th March 1880 in pursuance of an Order of the Lord Chancellor, and
dated the 6th September 1870
PROVISIONAL SPECIFICATION left by the said Alfred Lambotte Doucet
at the Office of the Commissioners of Patents on the 6th September 1879.
ALFRED LAMBOTTE-DOUCET, of 39, Rue Royale, Brussels, in the Kingdom of
Belgium. "A NEW METHOD OF TREATING COPPER, LEAD, AND ZINC ORES, THE
CINDERS OF WORKERS IN THE PRECIOUS METALS, THE RESIDUE FROM RETORTS OF
ZINC FURNACES, THE SCHLAMS, THE ZINCIFEROUS AND ARGENTIFEROUS FUMES, AND
FOR THE EXTRACTION OF SILVER FROM COPPER AND LEAD ORES."

page_text: confident that the chlorisation is complete I raise the temperature, and I direct
into the furnace, continually or intermittently, according to circumstances, a current
of atmospheric air, warm or cold, without the assistance of which the chlorides
formed could not be volatilized. Accordingly as they are volatilized the chlorides
arrive and are condensed in the condensation chambers, which are placed in com-
munication with the furnace. Into these, water is introduced in the shape of rain,
whether hot or coldi varies according to the nature of the chlorides. Finally, I
decompose by a galvanic method the chlorides drawn in solution from the conden-
sation chambers. In this way I obtain the metals in a pure state and I reconstitute
the chlorhydric acid.
TREATMENT OF ARGENTIFEROUS GALENA (SULPHIDE OF LEAD) AND OF SULPHIDE
OF COPPER. (
*
The ore is melted with a flux composed of an equivalent of carbonate of soda
and an equivalent of carbonate of potash, together with charcoal (carbone) added
to six parts of nitrate ("azotate") of potash. These proportions are very variable
and depend entirely on the richness and nature of the ore. The carbon must
always be in excess in order that the sulpho-salts (Pbs., Nas.) and the sulphate
(Nao, So³) produced in the chemical reaction mentioned above should; be decomposed
and completely transformed into metal and into alkaline sulphides. These alkaline
sulphides increase the fluidity of the mass and preserve the metal while in fusion
from oxidisation. These sulphides are easily soluble in water, therefore, nothing is
easier than to separate them from the metallic lead by a simple lixiviation, and
afterwards to reconstitute them and make use of their constituent parts in sub-
sequent operations. The lead thus obtained is run into crucibles (similar to those
used in the process of extracting silver from lead by means of chrystillisation).
These crucibles, which have been previously warmed so that they may not lower
the temperature of the metal in fusion, receive in this state a sufficient quantity of
zincate of soda, calculated by the proportion of silver contained. The temperature
is then raised to 540° centigrade. The contents of each crucible is carefully stirred
to ensure their being completely mixed together. Immediately after this stirring I
introduce into the molten metallic mass several copper wires furnished with copper
handles, which I place in connection with the poles of a thermo electric pile with a
continuous current. The zincate of soda is decomposed, the zinc and the soda
are set at liberty. After 20 minutes I withdraw.the copper wires and destroy the
connection with the pile, and I lower the temperature to 430° centigrade to facili-
tate the solidification of the alloy of zinc and silver, which, with the alkaline 'scoria,
separate of their own accord from the molten metallic mass. By subsequently
distilling this alloy in a suitable retort (ad hoc) I obtain the zinc, which is volatilized
and the silver remains, the sole residu from the operation; .I.melt it and cast it in
lingots.
TREATMENT OF CINDERS OF
OF WORKERS IN THE PRECIOUS METALS..
I form alloys in variable proportions of copper, lead, and antimony by pricipitating
with zinc or iron a solution of these metals in the presence of the gold and silver
contained in the crushed ore or metal' workers' cinders which are to be operated
upon. I then melt the alloy thus obtained in an easily fusible alkaline bath
composed, according to circumstances, of, hydrate of soda and of potash, or of
carbonate of soda and of potash in equal portions. I thus obtain with the assistance.
of the above named metals a cast of lead, copper, and antimony,, which contain in
a very reduced compass the whole of the gold and silver which was disseminated in
L

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and of
an Order of the Lord Chancellor filed by the said Alfred Lambotte-Doucet in
the Great Seal Patent Office on the 16th March 1880.
ALFRED LAMBOTTE-DOUCET, of 39, Rue Royale, Brussels, in the Kingdom of
Belgium. "A NEW METHOD OF TREATING COPPER, LEAD, AND ZINC ORES, THE
CINDERS OF WORKERS IN THE PRECIOUS METALS, THE RESIDUE FROM RETORTS OF
ZINC FURNACES, THE SCHLAMS, THE ZINCIFEROUS AND ARGENTIFEROUS FUMES, AND
FOR THE EXTRACTION OF SILVER FROM COPPER AND LEAD ORES."
•
Treatment of Copper, Lead, and Zinc Ores.-The treatment is divided into three
distinct operations,-first, the transforming the sulphides of copper, lead, and zinc
into chlorides by means of the vapours of chlorhydric-anhydric acid acting under
variable pressures; second, the volatilization in a current of atmospheric air of the
chlorides formed, which I collect into condensation chambers; third, the decom-
position by galvanism of the chlorides thus obtained.
Method of Application.-I introduce the ore reduced to powder and moistened
with sulphydric acid, in proportion to its nature and richness, into a reverberatory
furnace containing a muffle, or into any other suitable vessel connected with one or
several condensation chambers. I warm it gradually to a dull red in a current of
chlorhydric acid under pressure. The chlorhydric acid is previously dishydrated
by one of the known methods. By a twofold decomposition the chlorine combines
with the metals, while the hydrogen in the acid combines with the sulphur in the
ores and produces sulphydric acid (hydrogène sulphuré), which passes off in vapour.
When I am confident that the chlorination is complete I raise the temperature and
I direct into the retort (furnace), continually or intermittently, according to the
circumstances, a current of atmospheric air, warm or cold, without the assistance of
which the chlorides formed could not be volatilized. Accordingly as they are
valatilized the chlorides arrive in the condensation chambers, where they are
condensed, these condensation chambers being placed in communication with the
retort. Into these water is introduced in the shape of rain, whether hot or cold
varies according to the nature of the chlorides. Finally, I decompose the metallic
chlorides (in solution) obtained by the above or any other method by means of
thermo-electric currents, which liberate at the positive pole of the battery the
chlorine of the acid (which I collect) and at the negative pole the metal which
accumulates there. I generate these electric currents by means of the superfluous
heat of my heating chambers and furnaces acting in closed metallic circuits. The
circuits are composed either of one metal only or of two different metals formed
into large wires placed together and formed into bundles (strands), then twisted
together and subjected to great pressure so as to form a metallic rope, along which
the current passes. The two ends of the circuit are joined together and closed by a
small plate of soft iron magnetised. I can produce thermo-electric currents by
means of other bodies which are good conductors as well as by means of metals;
for instance, peroxide of manganese, sulphides of iron, lead, copper (copper pyrites),
etcetera. Each closed circuit of the metallic cord forms an element; several
elements together form a thermo-electric battery. The elements are grouped in
series of fifty to a hundred (the number is very variable, according to the intensity
required from the current) ranged vertically side by side and jointed together by
large wires of copper in such a way that the last bismuth of each series (if, for
instance, I have used bismuth to form the circuit) is joined by a powerful twist,
and even by a slight fusion, to the antimony of the following series, the result
being that the two poles correspond with two stems. In order to supply them I
enclose the elements with which I wish to form a thermo-electric battery in a
metallic enclosure of any form (the interior of which is coated with a light lining
not easily melted), into which the superfluous heat coming from some furnace, and

page_text: which is to generate the thermo-electric current, penetrates and circulates. At the
same time the whole of the, exterior is acted upon by a rapid current of air,
previously cooled to about freezing point by its automatic passage through a
refrigerating mass. In this way I'obtain the two extremities of temperature, the
electric effect of which is most intense.
Treatment of Silver Producing Sulphide (Galena) of Lead and of Sulphide of
Copper. The ore is melted with a flux composed of an equivalent of carbonate of
soda and an equivalent of oarbonate of potash, together with charcoal (carbon)
added to six parts of nitrate (azotate) of potash. These proportions are very
The carbon
variable and depend entirely on the richness & nature of the ore.
must always be in excess in order that the sulphosalts (Pbs., Nas.) and the sulphates
(Nao., So) produced in the chemical reactions mentioned above should be decom-
posed and completely transformed into metal and into alkaline sulphides. These
alkaline sulphides increase the fluidity of the mass and preserve the metal while in
fusion from oxidisation. These sulphides are easily soluble in water, therefore
nothing is easier than to separate them from the metallic lead by a simple lixiviation
and afterwards to reconstitute them and make use of their constituent parts in
subsequent operations. The lead thus obtained is run into crucibles (similar to
those used in the process of extracting silver from lead by means of chrystillization).
These crucibles, which have been previously warmed so that they may not lower
the temperature of the metal in fusion, receive in this state a sufficient quantity of
zincate of soda, calculated by the proportion of silver contained. The temperature
is then raised to 540 degrees centigrade. The contents of each crucible is carefully
stirred to ensure their being completely mixed together. Immediately after this
stirring I introduce into the molten metallic mass several copper wires furnished
with copper handles, which I place in communication with the poles of a thermo-
electric pile with a continuous current. The zincate of soda is decomposed; the
zinc and the soda are set at liberty. After twenty minutes I withdraw the copper
wires and destroy the connection with the pile, and I lower the temperature to
430 degrees centigrade to facilitate the solidification of the alloy of zinc and silver,
which with the alkaline scoria separates of its own accord from the molten metallic
mass.. By subsequently distilling this alloy in a suitable retort (ad hoc) I obtain
the zinc which is volatilized, & the silver remains the sole residue of the
operation; I melt it and cast it in lingots.
Treatment of the Cinders of Workers in the Precious Metals.-I form alloys in
variable proportions of copper, lead, and antimony by precipitating with zinc or
iron a solution of these metals in the presence of the gold and silver contained in
the crushed ore or metal-workers' cinders which are to be operated upon. I then
melt the alloy thus obtained in an easily fusible alkaline bath, composed according
to circumstances of hydrate of soda and of potash, or of carbonate of soda and of
potash in equal portions. I thus obtain with the assistance of the above named
metals a cast of lead, copper, and antimony which contains in a very reduced
.compass the whole of the gold and silver which was disseminated in their original
or mixed state throughout the auriferous and argentiferous matters thus treated.
To sum up, I claim by these Letters Patent as my Invention and my exclusive
property, which I place under the protection of the law,-First. The method of
transforming the sulphides of copper, lead, and zinc into chlorides by means of the
vapours of chlorhydric-auhydric acid, acting under pressure according to the
following rule, which forms the basis of the operation: If metallic sulphides are
heated in presence of chlorhydric anhydric acid sulphydric acid (hydrogène sulfuré)
is obtained, which passes off in vapour, and chlorides are obtained, corresponding
with the metallic sulphides treated according to the formula, Cu S+ Pb S+Zn S+
Ag S+4H Cl=Cu Cl + Pb Cl+Zn Cl+Ag Cl+4HS. I reserve to myself the right
of making use of chlorhydric-anhydric acid (or hydraté) as also of replacing
sulphides by the oxides of the same metals, according to the process Cuo + Pbo+
Zno+Ago +4Hcl=Cu, Cl + Pb, Cl + Zn, Cl + Ag, Cl+4Ho. Second. The method
which I adopt to volatilize the chlorides formed, as explained above, by means of a

page_text: current of air, whether or not mixed with chlorhydric acid, hot or cold, provided
with a suitable speed and pressure and made to act continuously or intermittently,
without the assistance of which the chlorides or bichlorides formed would not be
volatilized. Third. The method of decomposing the chlorides obtained as above
described, or in any other way, by means of the electric currents generated by the
simple and economical process explained in the first part of this description, notably
the way of preparing the electric cord, and of forming the elements provided with
a small casing of soft iron magnetised, which unites it with the following elements
and closes the circuit. Also the manner of obtaining in the circuit two extreme
temperatures, which afford as result the most intense electric effect, still further
increased by the permanent magnetisation of the soft iron coverings, which forms
an essential part of the system. Fourth. The method of transforming sulphide of
lead into metallic lead and of extracting the silver from it by means of the zinc
produced by zincate of soda, which is liberated in the molten metallic mass by one
of my thermo-electric batteries with a continuous current, and provided with a
commutator. The zinc gradually, as it is liberated, collects the silver and forms
with the metal an alloy which rises to the surface of the bath, while the soda
completes the purification of the lead by extracting from it the least trace of foreign
matters. Fifth. The method of forming metallic alloys by means of solutions of
copper, lead, and antimony by precipitating these metals in their first state with
iron or zinc in the presence of gold or silver ore or the cinders of workers in the
precious metals, and by producing as useful result a cast of lead, copper, and anti-
mony, with the property of concentrating. in the alloy all the gold and silver
without loss of the precious metals either by volatilization or otherwise, and
without leaving the least trace in the refuse.
In witness whereof, I, the said Alfred Lambotte Doucet, have hereunto set
my hand and seal, this Second day of March, in the year of our Lord
1880
Signed, sealed, and delivered, by the
said Alfred Lambotte Doucet, in
the presence of,
THOS. JAS. MALTBY,
H.B.M. Vice Consul,
at Brussels.
ALFRED LAMBOTTE-DOUCET. (1..s.)