A. PROCESS FOR THE WET EXTRACTION OF LEAD, SILVER COPPER, NICKEL, AND COBALT FROM ORES AND MATTS CONTAINING THESE METALS
Year: 1881

page_text: LETTERS PATENT to Herbert John Haddan, of Kensington, Middlesex, for an
Invention of "A. PROCESS FOR THE WET EXTRACTION OF LEAD, SILVER
COPPER, NICKEL, AND COBALT FROM ORES AND MATTS CONTAINING THESE
METALS." A communication from abroad by Alexis Drouin, of Paris,
France.
PROVISIONAL SPECIFICATION left by the said Herbert John Hadḍan at the
Office of the Commissioners of Patents on the 22nd August 1881.
HERBERT JOHN HADDAN, of Kensington, Middlesex.
"A. PROCESS FOR THE
WET EXTRACTION OF LEAD, SILVER, COPPER, NICKEL, AND COBALT FROM ORES
AND MATTS CONTAINING THESE METALS." A communication from abroad by
Alexis Drouin, of Paris, France.
The wet extraction of lead, silver, copper, nickel, and cobalt from their ores
offers many difficulties, especially in presence of arsenic and antimony. The
process which I am now going to describe allows however of extracting these
metals from their ores, producing them in a state of great purity, and separating
them when they or several of them are contained in the same ore. This Invention
may also be applied for extracting these metals from the residues of the mechanical
treatment of lead ores. These residues, consisting of a fine powder, are too poor
for being used in foundries, and they cannot be mechanically enriched without
losing a considerable portion of their metallic contents. It will therefore be readily
understood that an economical process for utilizing these residues, by extracting
the metals they contain, must be of the utmost importance for the working of
mines. The new process, which constitutes the object of this Invention, consists
in binding with chlorine, and at a low temperature, the metals contained in the
ores and the matts. When the ore contains lead it is treated hot with a solution
of sea-salt and an acid in proportions varying according to the case. This operation
is performed in wooden vessels provided with a double bottom, serving as a filter,
on which the powdered ores are placed about 40 to 50 centimetres high, and then
the dissolving liquid is let in through a leaden pipe, having previously been
prepared in a reservoir placed on a higher level than the above vessel. When the

page_text: treatment is to be effected at a high temperature the mixture of ore and liquid is
heated by steam to a temperature of about 80 or 90° (centigrade) by means of
special heating arrangements. When the ore contains neither lead nor silver, the
metals are extracted without the application of heat, and the arrangement of the
vessels is very much simplified. The treatment of the ores and matts by this
new process consists of the following five operations :—
-
1st, grinding; 2nd, roasting; 3rd, binding of the metals by chlorine and disso-
lution; 4th, precipitation of the dissolved metals; 5th, washing, drying, and casting
of the precipitated metals.
Grinding. The ores and matts may be ground with water power and by any
known apparatus, so as to reduce the above into fine powder.
Roasting. The ores must be roasted in certain cases, if they contain copper,
nickel, or cobalt, but always at a low temperature, and in a strongly oxidizing
atmosphere. For the extraction of lead roasting is never needed, and thereby
volatilization completely avoided.
Dissolution and Binding.-The composition of the liquid for binding the metals
by chlorine and for the dissolution of the formed chlorides depends on the nature
of the ores. Generally the liquid contains 20 to 25% of salt, and 1 to 10% of
acid. The dissolving liquids may be used again after precipitation.
Precipitation. The precipitation of the metals may be effected cold or hot,
according to the nature of the metals. The dissolution of lead must be effected
hot, after which it will suffice to cool the liquid down, the silver having been
previously removed. The chloride of lead produces small white crystals, which
may be easily gathered: Copper is precipitated after cooling by means of metallic
iron. If the ore contains nickel or cobalt I submit the dissolution, after removing
the copper therefrom, to a current of chlorine for peroxydizing the metal-salts;
then I precipitate the iron by carbonate of lime. The nickel and cobalt are preci-
pitated from the filtered liquid in the state of oxydes by lime-water, and then
separated by one of the known processes. The use of chlorine for precipitating
copper, nickel, and cobalt may be dispensed with by using an alcaline sulphide.
The iron is removed very readily by submitting this mixture of sulphides to the
action of hydrochloric acid diluted with much water, whereby chloride of
iron is formed, which may be used like chloride of sodium for dissolving metals
under the conditions above mentioned. The sulphides of nickel and cobalt are
then roasted for obtaining pure oxydes by driving the sulphur out.
Washing, Drying, and Casting. The precipitated metals must be washed very
rapidly and with an abundance of water for removing the salts that they may
contain; then the metals are dried cold for avoiding oxydation; a hydraulic press
or drying apparatus may be used. Silver is cast in crucibles, the other metals in a
reverberatory furnace.
The chloride of lead thus obtained generally contains 73 to 75% of metallic
lead. It may be used in this state for manufacturing oxydes or salts of lead; or
the metal may be extracted by casting with coal and carbonate of lime.
For preparing the dissolving bath hydrochloric acid or sulphuric acid may be
used with the same results.
The advantages of my process are very numerous. Besides the perfect purity of
the products the amount of acid consumed is never greater than the amount
corresponding to the law of chemical equivalents. Moreover the dissolving liquid
can be used many times, and therefore the cost of extraction is very small.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Herbert John Haddan in the Great Seal Patent Office on the
22nd February 1882.
HERBERT JOHN HADDAN, of Kensington, Middlesex. "A PROCESS FOR THE
WET EXTRACTION OF LEAD, SILVER, COPPER, NICKEL, AND COBALT FROM ORES
AND MATTS CONTAINING THESE METALS." A communication from abroad by Alexis
Drouin, of Paris, France.
The
The wet extraction of lead, silver, copper, nickel, and cobalt from their ores
offers many difficulties, especially in presence of arsenic and antimony.
process which I am now going to describe allows however of extracting these
metals from their ores, producing them in a state of great purity, and separating
them when they or several of them are contained in the same ore. This Invention
may also be applied for extracting these metals from the residues of the mechanical
treatment of lead-ores. These residues, consisting of a fine powder, are too poor for
being used in foundries, and they cannot be mechanically enriched without losing
a considerable portion of their metallic contents. It will therefore be readily
understood that an economical process for utilizing these residues by extracting
the metals they contain must be of the utmost importance for the working of
mines. The new process, which constitutes the object of this Invention, consists
in binding with chlorine, and at a low temperature, the metals contained in the
ores and the matts.
When the ore contains lead it is treated hot with a solution of sea-salt and an
acid in proportions varying according to the case. This operation is performed in
wooden vessels provided with a double bottom, serving as a filter, on which the
powdered ores are placed about 40 to 50 centimetres high, and then the dissolving
liquid is let in through a leaden pipe, having previously been prepared in a
reservoir placed on a higher level than the above vessel. When the treatment is to
be effected at a high temperature, the mixture of ore and liquid is heated by steam
to a temperature of about 80 or 90° (centigrade) by means of special heating
arrangements. When the ore contains neither lead nor silver the metals are
extracted without the application of heat, and the arrangement of the vessels is
very much simplified. The treatment of the ores and matts by this new process
consists of the following five operations:-1st, grinding; 2nd, roasting; 3rd, binding
of the metals by chlorine and dissolution; 4th, precipitation of the dissolved metals;
5th, washing, drying, and casting of the precipitated metals.
Grinding. The ores and matts may be ground with water-power and by any
known apparatus, so as to reduce the above into fine powder.
Roasting. The ores must be roasted in certain cases if they contain copper,
nickel, or cobalt, but always at a low temperature and in a strongly oxydising
atmosphere. For the extraction of lead, roasting is never needed, and thereby
volatilization completely avoided.
Dissolution and Binding.-The composition of the liquid for binding the metals
by chlorine and for the dissolution of the formed chlorides depends on the nature
of the ores. Generally the liquid contains 20 to 25% of salt, and 1 to 10% of
acid. The dissolving liquids may be used again after precipitation.
Precipitation. The precipitation of the metals may be effected cold or hot,
according to the nature of the metals. The dissolution of lead must be effected
hot, after which it will suffice to cool the liquid down, the silver having been
previously removed. The chloride of lead produces small white crystals, which
may be easily gathered. Copper is precipitated after cooling by means of metallic
iron. If the ore contains nickel or cobalt I submit the solution, after removing the

page_text: copper therefrom, to a current of chlorine for peroxydizing the metal-salts; then I
precipitate the iron by carbonate of lime. The nickel and cobalt are precipitated
from the filtered liquid in the state of oxydes by lime-water, and then separated
by one of the known processes.
The use of chlorine for precipitating copper, nickel, and cobalt may be dispensed
with by using an alcaline sulphide. The iron is removed very readily by submitting
this mixture of sulphides to the action of hydrochloric acid diluted with much
water, whereby chloride of iron is formed, which may be used like chloride of
sodium for dissolving metals under the conditions above mentioned. The sulphides
of nickel and cobalt are then roasted for obtaining pure oxydes by driving the
sulphur out.
Washing, Drying, and Casting.-The precipitated metals must be washed very
rapidly and with an abundance of water for removing the salts they may contain ;
then the metals are dried cold for avoiding oxydation; a hydraulic press or drying
apparatus may be used. Silver is cast in crucibles, the other metals in a rever-
beratory furnace.
The chloride of lead thus obtained generally contains 73 to 75% of metallic
lead. It may be used in this state for manufacturing oxydes or salts of lead ;_or
the metal may be extracted by casting with coal and carbonate of lime. For
preparing the dissolving bath hydrochloric acid or sulphuric acid may be used with
the same results.
The advantages of this process are very numerous. Besides the perfect purity
of the products, the amount of acid consumed is never greater than the amount
corresponding to the law of chemical equivalents. Moreover the dissolving liquid
can be used many times, and therefore the cost of extraction is very small.