Improvements in the Electrolytic Process of Obtaining Copper, Zinc, and Tin.
Year: 1889

page_text: Date of Application, 20th Mar., 1889
Complete Specification Loft, 16th Dec 1880 Accented. 22nd Feb. 1890
PROVISIONAL SPECIFICATION.
Improvements in the Electrolytic Process of Obtaining Copper,
Zinc, and Tin.
I, Hermann Albert Seegall Chemist of 129 Invaliden Strasse, Berlin, Germany,
do hereby declare the nature of this invention to be as follows
The method discovered by me has many advantages over the processes for
lixiviating substances for electrolytically obtaining copper, zinc and tin, used up to
the present. The methods known up to this time for lixiviating and electrolysing
can only be applied, when, the substance to be treated only contains the desired
metal, or at most very small quantities of other metals, which can be separated
electrolytically and then the solutions resulting from the lixiviation require a great
deal of electricity for their decomposition; at the same time they must be kept very
acid in order to be good conductors.
By my newly discovered process I am able to overcome these difficulties. The
solutions resulting from the lixiviation do not need more than half the quantity of
electricity for their decomposition, used up to the present. The presence of the
atmospheric air has no very injurious oxydizing effect. The greatest advantage is
perhaps, that when two or three different metals are combined in the substance to be
lixiviated, it is possible to separate them easily.
Lastly the presence of arsenic, which has been reckoned, up to the present, as a
most unpleasant pollution in electrolytic processes, works advantageously in my
process as it hinders the formation of oxychlorides.
The above advantages are obtained by the use of ferrihalogeneous combinations
for lixiviating purposes in all suitable cases for electrolyzing, which has not been
done up to the present.
My discovery is useful for obtaining copper, zinc and tinc, separate or combined,
from materials containing these metals in the form of metals, alloys with other
metals, or in combination with metalloids, by lixiviation and electrolysis.
I lixiviate the above mentioned materials with a solution of sosquichloride, sosqui-
bromide or sesquijodide of iron (Fe, Cl; Fe, Br.; Fe, T') and then treat them
electrolytically.
The lixiviation can be conducted better out of the bath, that is to say before
the electrolytic process begins, it is, however, possible to conduct both together.
I use as anode :
a) Carbon, if the lixiviation takes place out of the bath.
b) the substance to be worked, when the lixiviation takes place inside of the bath.
As cathodo I generally use copper, zinc or tin, according to which of these metals
shall be obtained.
It is advantageous to separate the two poles by means of a diaphragme.
The solubility of the cuprous chloride (Cu, Cl₂) is slight at the ordinary
temperature and moderate concentration of the ferrouschloride (Fe Cl,) solution,
which is advantageous for this process especially on account of the oxychlorides of
iron formed and the presence of other metals.
The slight quantity of hydrochloric acid added, also produces a very weak
dissolving power. On account of this a soluble halogeneous salt, which neither
precipitates iron nor copper, but dissolves cuprous chloride (Cu, Cl,) such as chloride
of calcium (Ca Cl₂) or a halogeneous acid must be added to the ferrihalogeneous
solution, or to the substance to be lixiviated.
The ferrous combinations (Fe Cl.. Fe T,, Fe Br.) produced by the lixiviation and

page_text: In the use of anodes, electrolytically insoluble, the motion of the lixivium must
follow from the cathode to the anode.
The chemical reactions, which take place in the lixiviation and electrolysis will
be seen from the following equations:
a) For ores which only contain copper in combination with metalloids (M):

page_text: of the presence of other metals)-the oxychlorides of iron (2 Fc, Cl + 25 Fe₂ 0, +
41 H, O)-formed from the same cause-and possibly a little sulphur, romain
suspended therein.
This solution is passed through a filter, where the above named suspended (that
is to say undissolved) substances remain back, and then into the electrolytic baths
where the zinc is precipitated.
I b). The cuprous chloride (Cu, Cl₂), which remains in the filter is then put into
the troughs together with metallic copper (copper cuttings or filings) and so long
lixivated with a concentrated solution of sesquichloride of iron, slightly aciditated
with hydrochloric acid until only a very little of the sesquichloride of iron
remains.
This solution must contain a sufficient quantity of a salt, such as chloride of
calcium or chloride of sodium in order to hold the cuprous chloride in solution.
This lixivium is then passed through a filter in order to eliminate the suspended
sulphur and then into the electrolytic baths to obtain the copper.
II a). Is it desired to work a material containing copper and tin as alloys, for
instance metallic cuttings, the same inust be lixiviatod with a moderately con-
centrated solution of sesquichlorido of iron slightly aciditated with hydrochloric
acid, until all or nearly all of the sesquichloride of iron has been resolved into
protochloride of iron.
The resulting combination contains all the protochloride of iron and of tin in
solution, whilst the principle mass of the cuprous chloride together with a littlo
metallic copper deposited in a spongy form, as well as some oxychlorides of iron
(as mentioned under I a) remain suspended. The solution is now passed, through a
Alter, where everything which is not dissolved, remains back, and then into, the,
electrolytic baths where the tin is obtained.
II). The cuprous chloride which has remained in the filter, is treated in tho
manner described in I b and is then placed in the electrolytic baths for obtaining the
copper.
The course of the above named lixivia is the following: from the cathode-cell of
the first bath to that of the second, from there to that of the third and so on; from
the cathode-cell of the last bath into the anode-cell of the first and from this to
that of the second and so on; then from the anode-cell of the last bath into the
troughs again for new lixiviation.
The residuum in the troughs can be worked on precious metals.
HERMANN ALBERT SEEGALL.
By A. Kuhnt & R. Deissler,
38, Alexander Strasse, Berlin C, Germany, Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in the Electrolytic Process of Obtaining Copper, Zinc,
and Tin.
I, HERMANN ALBERT SEEGALL of 129 Invalidenstreet Berlin, N. Germany,
manufacturer, 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 :-
The method discovered by me has many advantages over the processes for obtaining
Copper, Zinc and Tin, used up to the present. The methods known up to this time
for lixiviating and electrolysing can only be applied, when the substance to be treated
only contains the desired metal, or at most very small quantities of other metals,
which can be separated electrolytically and then the solutions resulting from the
lixiviation require a strong, and continuous current of electricity for their
decomposition; at the same time they must be kept very acid in order to be good
conductors.

page_text: By my process I am able to overcome these difficulties. The solutions resulting
from the lixiviation do not need more than half the quantity of electricity for their
decomposition, used up to the present. The presence of the atmospheric air has no very
injurious oxydizing effect. The greatest advantage is perhaps, that, when two or three
different metals are combined in the substance to be lixiviated, it is possible to separate
them easily.
Lastly the presence of arsenic, which has been reckoned up to the present, as a most
unpleasant pollution in electrolytic processes, works advantageously in my process,
as it hinders the formation of oxychlorides.
My discovery is useful for obtaining copper, zinc and tin from materials containing
copper, or copper with zinc or tin in the form of metals, alloys, alloys with other
metals or in combination with metalloids by combined lixiviation and electrolytic
processes.
I lixiviate the above mentioned materials with a solution of sesquichloride of
iron (Fe, Cl).
The principal features of the discovery consist in first separating from the solution
of other metals and impurities the undissolved cuprous chloride, which has been
obtained in the known manner by reaction and lixiviation with ferric chloride of the
mentioned materials; secondly, extracting the other metals from this solution; thirdly,
dissolving or lixiviating the undissolved cuprous chloride with halogen salts or halogen
acids or any of the well known means of dissolving cuprous chloride (sodium
hyposulphite etc.), and thus obtaining cuprous chloride in solution.
This cuprous
chloride solution is treated electrolytically in the presence of ferrous chlorido, by
which means pure copper and ferric chloride are obtained, and at the same time any
injurious developement of the chlorine is avoided.
I am well aware, that prior to my discovery materials containing copper have been
subjected to a lixiviation process with ferric chloride, with a view to change them
but in this treatment the main idea was to gain cuprous chloride with a view of
afterwards obtaining copper electrolytically, and the process was so conducted, that
if any cuprous chloride was formed, it was always converted into cupric chloride;
undissolved cuprous chloride was in no case formed and separated from the
lixivium.
With a view to obtain cement copper the lixiviation was conducted in such a
manner, that forined cuprous chloride was also dissolved; but at the precipitation
the cuprous chloride was not separated, nor was it separately subjected to a second
lixiviation.
I conduct my lixiviation with the aid of two different lixivia and in two separate
operations. In the first operation obtain undissolved cuprous chloride by reaction
with ferric chloride, and in the second I dissolve the separated undissolved chemically-
unaltered cuprous chloride. This conversion and lixivation of the undissolved
chemically-unaltered caprous chloride, obtained by reaction of ferri-halogens into
cuprous chloride solution, is entirely new in the combined lixiviation and electrolytic
process constituting the present discovery. The electrolytic part of the process is
also new that is, the electrolytical treatment of the cuprous chloride in the presence
of ferrous chloride either dissolved together or separated by a diaphragm.
It has not yet been attempted to treat cuprous chloride electrolytically in the
presence of ferrous chloride in spite of the fact, that by this means the greatest
possible extraction of copper is attained by the least amount of electrical power, and
in spite of the fact, that, besides this, the process has another great advantage, which
is the easy elimination of all impurities of the copper through other metals (arsenic)
in the lixiviation process.
This new process consists in lixiviating the material containing the copper with
ferric chloride (Fe, (1) so long until the ferric chloride (Fe, C) is converted into
ferrous chloride (Fe Cl) and undissolved cuprous chloride (Cu, C) has been produced.
This undissolved cuprous chloride (Cu, Cl₂) is then separated by filtration from the
lixivium which retains the other metals and impurities, (arsonic). The undissolved
cuprous chlorido separated from the lixivium is then subjected to a second lixiviation

page_text: with a halogen acid or halogen salt, or with another agent dissolving cuprous chloride,
(Cu, Cl) adding, eventually, a combination of iron with chlorine. Under the term
combination of iron with chlorine" I understand either a ferrous chloride (Fe CI,)
or a ferric chloride with a reducing agent.
In lixiviating without the addition of a combination of iron with chlorine a cuprous
chloride solution (Cu, Cl₂) will be obtained, which is treated in the electrolytic process
in the presence of ferrous chloride, (that is to say, either dissolved together or separated
from each other by a diaphragm,) whereby a very pure copper is obtained.
The practical working of the process is described in the following examples:
1a. If it be desired to work a substance containing copper and zinc together, either
as metals or as sulphides, the substance must be ground or otherwise broken up into
sufficiently small pieces and lixiviated in troughs with a moderately-concentrated
solution of sesquichloride of iron slightly acidulated by hydrochloric acid until the
whole sesquichloride of iron with the exception of a very little has been resolved into
ferrous chloride. The resulting solution contains all the ferrous chloride (Fe Cl₂) and
zinc chloride (Zn Cl₂) dissolved, while the principal mass of the cuprous chloride,
(Cu, Cl₂) together with a little metallic copper deposited in a spongy form, (in
consequence of the presence of other metals,) the oxychlorides of iron,
27 Fe, Cl, +116 H, O= 2 Fe, Cl, + 25 Fe, O, + 41 H, O + 150 H Cl,
formed from the same cause, and possibly a little sulphur, remain suspended therein.
This solution is passed through a filter, where the above-named suspended (that is
to say, undissolved) substances remain back, and then into the electrolytic baths,
where the zinc is precipitated.
16. The cuprous chloride (Cu, Cl₂), which remains in the filter, is then put into the
troughs, together with metallic copper, (copper enttings or filings) and so long
lixiviated with a concentrated solution of sesquichloride of iron slightly acidulated
with hydrochloric acid until only a very little of the sesquichloride of iron remains.
This solution must contain a sufficient quantity of a salt such as chloride of calcium
or chloride of sodium-in order to hold the cuprous chloride in solution. This lixivium
is then passed through a filter in order to eliminate the suspended sulphur, and then
into the electrolytic baths to obtain the copper.
2 a. If it be desired to work a material containing copper and tin as alloys-for
instance, metallic cuttings-the same must be lixiviated with a moderately concentrated
solution of sesquichloride of iron slightly acidulated with hydrochloric acid until all
or nearly all of the susquichloride of iron has been resolved into protochloride of
iron. The resulting combination contains all the protochloride of iron and
of tin in solution, while the principal mass of the cuprous chloride, together with a
little metallic copper deposited in a spongy form, as well as some oxychlorides of iron,
(as inentioned under 1 a.) remain suspended. The solution is now passed through a
filter, where everything which is not dissolved remains back, and then into the
electrolytic baths, where the tin is obtained.
26. The cuprous chloride which has remained in the filter, is treated in the manner
described in 1b. and is then placed in the electrolytic baths for obtaining the copper.
The course of the above-named lixivia may be conducted through the electric baths
as follows:
The lixivium flows to the cathode-cell of the first electric bath, from this cathode-cell
into the cathode-cell of the second electric bath and passes so through the cathode-cells
of the following electric baths; then into the anode-cell of the first electric bath
from the cathode-cell of the last electric bath the lixivium in order to be again oxidized
is conducted and passes then through the anode-cells of the following electric baths.
From the anode-cell of the last electric bath the oxidized lixivium flows again into the
lixiviating-troughs in order to lixiviate again the ores or materials.
I do not confine myself to the course of the lixivia in the electric baths mentioned
above. This course may be chosen as considered compatible with the practice. The
residuum in the troughs can be worked on precious metals.

page_text: 39
In the following claims I understand under the term: "materials containing copper
or "materials containing copper and zinc or tin" not only those materials containing
these metals as metals or as alloys, but also as an alloy with other metals and as com
bination with metalloids and in particular, ores, smelting products and metal
cuttings.
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 of obtaining copper from materials containing the same, consisting
in, first, lixiviating-copper containing material with ferric chlorido i secondly,
separating the undissolved cuprous chloride from the solution; thirdly, dissolving
the undissolved cuprous chloride, and then treating electrolytically the cuprous chloride
solution, for the purpose as described.
2. The process of obtaining copper from materials containing the same, consisting
in, first, lixiviating copper-containing material with ferric chloride; secondly,
separating the undissolved cuprous chloride from the solution; thirdly, dissolving the
undissolved cuprous chloride, and then treating electrolytically the cuprous chloride
solution in the presence of ferrous chloride, for the purpose as described.
3. The process of obtaining a solution containing zinc or tin, from materials in
which these elements in combination with copper are present, consisting in lixiviating
the said materials with ferric chloride and separating the insoluble cuprous chloride
from the lixivia thus obtained, so that the resulting solution contains chloride of zinc
or chloride of tin, from which zinc or tin may be obtained in the known manner.
Dated Berlin, this 18th day of December 1889.
HERMANN ALBERT SEEGALL.
By A. Kuhnt & R. Deissler,
33, Alexander Strasse, Berlin C, Germany, Agents for Applicant.