An Improved Method of Treating Cupreous Liquors for the Purpose of Utilizing the same.
Year: 1890

page_text: Date of Application, 10th Nov., 189C
Complete Specification Left, 7th Aug., 1891--Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
An Improved Method of Treating Cupreous Liquors for the Purpose
of Utilizing the same.
I, Dr. CARL HÖPFNER, of 36, Frankfurter Strasse, Giessen, in the Empire of
Germany, do hereby declare the nature of this invention to be as follows:-
This invention relates to a method of treating cupreous liquors for the purpose
of utilizing the same.
For utilizing cupreous liquors, such as are obtained in well-known metallurgical
processes, I proceed as follows:-
If the liquor contains the copper in the form of a sulphate, it is mixed with an
equivalent quantity of common salt or other chloride, such as potassium chloride.
If however the liquor contains copper in the form of a halogen compound with an
excess of common salt it is mixed with copper sulphate or other suitable metallic
sulphate the quantity of which corresponds to this excess of common salt.
By this means I obtain a solution containing copper chloride besides Glauber's
salt. This copper chloride solution is now treated with metallic copper in a
stirring apparatus.
By the action of the metallic copper is produced insoluble cuprous chloride, and
at the same time any silver which may be present in the solution is precipitated in
the form of a metal.
The remaining mother-liquor contains only traces of copper, small quantities of
iron, nickel, and the like and is adapted for the extraction of Glauber's salt. By
precipitants which are well known in chemistry, and which may be either oxides,
carbonates, or sulphides, these metallic salts can be removed, thereby enabling a
pure salt to be obtained.
In case free acid is contained in the liquors it is preferably utilized either by
cupric oxide or by cuprous oxide.
For precipitating the copper from the chloride liquors use can be made of
cuprous sulphide, cuprous oxide or cuprous carbonate either partly or wholly in
lieu of copper. Iron, manganese and other metals present in the liquor are thereby
also precipitated. The necessary cuprous oxide is produced in the simplest manner
by treating the cuprous chloride with caustic lime, whereby a precipitate containing
cuprous oxide is produced.
The precipitates obtained in the above described manner, which may contain
silver, copper, cuprous oxide, cuprous chloride, cupric oxide, are suitably dissolved
in the form of cuprous chloride so as to free the solution from silver, bismuth,
arsenic and antimony. It is then treated at the cathodes of an electrolytic bath in
order to obtain pure copper.
Or the precipitates of copper or their solutions are treated in a suitable manner
with caustic lime, and the oxide or protoxide obtained is utilized by the dry
method. The cuprous oxide may also be converted in the well-known manner into
a sulphate.
Of course the precipitates or their solutions can also be reduced by iron or other
metals.
If the improved process is to be used for treating copper liquors, such as occur
after the chlorination-roasting of burnt copper pyrites, the salts contained therein
especially the Glauber salt, being completely extracted they are treated with finely
divided copper in a stirring apparatus of the kind generally used in practice. In
this manner the cupric chloride contained in the copper liquor is transformed into
an insoluble cuprous chloride, whereupon the liquor which has become almost free

page_text: from copper can as above stated be purified and treated for obtaining Glauber's
salt by precipitating the metallic salts still contained therein.
As very frequently the oxidation and chlorination roasting of the pyrites is at
some points incomplete, and as the burnt cupreous pyrites from which the liquors
are to be obtained should preferably contain the copper in the form of a chloride or
a sulphate, or in the form of an oxide which is soluble in sulphuric acid, it is
expedient to extract the copper pyrites which has become magnetic by reason of
the high temperature and the magnetic pyrites from the burnt pyrites through
the medium of magnets, and to subject this magnetic portion to a separate
treatment.
Dated this 10th day of November 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Method of Treating Cupreous Liquors for the Purpose
of Utilizing the same.
I, Dr. CARL HÖPFNER, of 36, Frankfurter Strasse, Giessen, in the Empire of
Germany, 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 a method of treating cupreous liquors for the purpose
of utilizing the same.
For utilizing cupreous liquors, such as are obtained in well-known metallurgical
processes, I proceed as follows:
If the liquor contains the copper in the form of a sulphate, it is mixed with an
equivalent quantity of common salt or other chloride, such as potassium chloride.
If however the liquor contains copper in the form of a halogen compound with an
excess of common salt it is mixed with copper sulphate or other suitable metallic
sulphate the quantity of which corresponds to this excess of common salt.
By this means I obtain a solution containing copper chloride besides Glauber's
salt. This copper chloride solution is now treated with metallic copper in a
stirring apparatus.
By the action of the metallic copper is produced insoluble cupreous chloride,
and at the same time any silver which may be present in the solution is precipitated
in the form of a metal.
The remaining mother-liquor contains only traces of copper, small quantities of
iron, nickel, and the like, and is adapted for the extraction of Glauber's salt. By
precipitants which are well known in chemistry, and which may be either oxides,
carbonates, or sulphides, these metallic salts can be removed, thereby enabling a
pure salt to be obtained.
In case free acid is contained in the liquors it is preferably neutralized either by
cupric oxide or by cuprous oxide.
For precipitating the copper from the chloride liquors use can be made of
cuprous sulphide, cuprous oxide or cuprous carbonate either partly or wholly in lieu
of copper. Iron, manganese and other metals present in the liquor are thereby also
precipitated. The necessary cuprous oxide is produced in the simplest manner by
treating the cuprous chloride with caustic lime, whereby a precipitate containing
cuprous oxide is produced.
The precipitates obtained in the above-described manner, which may contain
silver, copper, cuprous oxide, cuprous chloride, cupric oxide, are suitably dissolved
in the form of cuprous chloride so as to free the solution from silver, bismuth,
arsenic and autimony.
This dissolution is effected by a neutral or alkaline solution of a chloride
dissolving the cuprous chloride, such as for instance sodium chloride, potassium

page_text: chloride, calcium chloride, magnesium chloride or the like.
Silver, bismuth,
arsenic, antimony, remain behind undissolved as a metal or as an oxidized com-
pound, whilst cuprous chloride is dissolved. The solution of copper thus obtained
which is preferably separated in a suitable manner from the residue, and is now
pure, is electrolysed thereby reducing it to copper at the cathodes.
Or the precipitates of copper or their purified solutions containing cuprous
chloride are treated in a suitable manner with caustic lime. Chloride of lime is
formed and the oxide or protoxide of copper obtained is utilized by any other
method. The cuprous oxide may also be converted in the well known manner into
a sulphate e.g. according to the following equation
Cu₂O + H₂SO = CuSO₁ + H₂O + Cu.
Of course the precipitates or their solutions can also be reduced by iron or other
metals.
If the improved process is to be used for treating copper liquors, such as occur
after the chlorination-roasting of burnt copper pyrites, the salts contained therein,
especially the Glauber salt, being completely extracted they are treated with finely
divided copper in a stirring apparatus of the kind generally used in practice. In
this manner the cupric chloride contained in the copper liquor is transformed into
an insoluble cuprous chloride, whereupon the liquor which has become almost free
from copper can as above stated be purified and treated for obtaining Glauber's
salt by precipitating the metallic salts still contained therein.
As the oxidation and chlorination roasting of the pyrites is at some points very
frequently incomplete, and as the burnt cupreous pyrites from which the liquors
are to be obtained should preferably contain the copper in the form of a chloride or
a sulphate, or in the forin of an oxide which is soluble in sulphuric acid, it is
necessary according to the present invention to extract the copper pyrites which
has become magnetic by reason of the high temperature and the magnetic pyrites
from the burnt pyrites through the medium of magnets, and to subject this
magnetic portion to a separate treatment.
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 :-
First. The treatment of cupreous liquors, more especially such as have been
obtained by the extraction of ores subjected to chlorination-roasting or burnt
pyrites, in such a manner that after previously adding equivalent quantities of
common salt or other chlorides such as potassium chloride, or after adding sulphates
such as copper sulphate, the silver contained therein is precipitated by metallic
copper as a metal, whereas the copper is precipitated in the form of a chloride, and
the remaining mother liquor, after being purified and freed from iron by oxides or
sulphides may be used for extracting the alkaline sulphate contained therein,
substantially as set forth.
Second. In the process for obtaining copper from liquors as above set forth
wholly or partially substituting metallic copper which acts as a precipitant by
cuprous oxide, cuprous sulphide or cuprous carbonate substantially as set forth.
Third. In the above described process the electrolytic extraction of copper in
such a manner that from the cupreous precipitates obtained, which may contain
netallic copper, cuprous oxide, cupric oxide, cuprous sulphide, cuprous chloride,
pure solutions of copper, that is to say, such as are free from silver, bismuth,
arsenic and antimony are produced and are electrolized at the cathodes of an
electrolytic bath, substantially as set forth.
Fourth. In the process hereinbefore described the treatment of the copper
precipitate or a solution of the same with metals, alkalies or alkaline earths or their
carbonates, more especially with caustic lime, in order to form metallic copper,
cupric oxide or cuprous oxide which can be reduced to metal by the dry method,
substantially as set forth.

page_text: Fifth. The separation of copper sulphide or defectively roasted copper ore and
iron pyrites from burnt pyrites by the magnetic method so that the burnt pyrites
are obtained as free as possible from these substances and are rendered suitable for
the treatment hereinbefore described, substantially as set forth.
Dated this 7th day of August 1891.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.