IMPROVEMENTS IN THE REDUC- TION OF METALLIC ORES
Year: 1883

page_text: LETTERS PATENT to Stephen Henry Emmons, of Soho Square, in the County
of Middlesex, Actuary for an Invention of "IMPROVEMENTS IN THE REDUC-
TION OF METALLIC ORES
"
PROVISIONAL SPECIFICATION left by the said Stephen Henry Emmens
at the Office of the Commissioners of Patents on the 15th January 1883.
STEPHEN HENRY EMMENS, of Soho Square, in the County of Middlesex; Actuary,
"IMPROVEMENTS IN THE REDUCTION OF METALLIC ORES"
My invention relates to the electrolytical reduction of metals from their ores,
and is designed to effect this by the electrolytical decomposition of solutions of the
salts of sodium, or other chemically equivalent salts, in the presence of such ores.
I may carry out my invention in the following manner. I first prepare the ore
for treatment by breaking it down to a coarse powder, or other suitable size,
according to the nature of the ore; and 1 then calcine it with or without the
addition of coke, culm, coal, charcoal or other reducing material; but in some
cases this calcination may be omitted without materially interfering with the
success of the operation.
After the ore is prepared as above mentioned, I place it in one compartment of a
tank of any suitable material and size, and divided into two compartments by
means of a porous diaphragm or partition. Each compartment is further provided
with an electrode or electrodes of carbon or other suitable material, and in some
cases 1 disseminate granules of carbon throughout the ore, in order to obtain a
greater uniformity of action. I then fill the tank with a solution of sodic chlorido,
sodic nitrate, or both combined, and I connect the electrodes with the poles of a
galvanic battery or dynamo, in such a fushion as to cause an electrical current to
How through the tank, from the ore to the opposite extremity. Nascent chlorine,
or nitric acid, or a mixture of the two, is thus evolved in the oro compartment,
and acts on the metals contained in the ore and gradually dissolves them, its action
being in some cases assisted by a jet of steam or other source of heat. At suitable
intervals the liquors are drawn off from the two compartments and are mixed
Price 411

page_text: together, in which case the metals in solution are precipitated, by means of the free
alkali derived from the electrolytic decomposition of the original salt; and then
the supernatant liquid is ready to be used again for the treatment of a fresh parcel
of ore.
The ordinary method of precipitation by metallic iron or zinc may how-
ever be employed if preferred, or the metallic solution may be electrolytically
decomposed.
I do not always employ a tank divided into compartments as above described. I
sometimes put the ore in a porous tank or casing, placed in an outer tank; and
sometimes I simply place the ore at the bottom of a tank, and fix the negative
electrode in the supernatant fluid. In this latter case, which is especially suitable
for ores containing gold and silver, I prefer to place a receiver under the negative
electrode, to catch any metallic deposit that may drop away from such electrode,
and I furthermore add some potassic cyanide or sodic byposulphite to the working
solution, where the extraction of gold or silver is desired.
In some cases I carry the preliminary furnace reduction of the ore, to the extent
of producing a regulus, which I then connect up as an anode in the reduction tank,
and proceed as before mentioned.
In cases where metallic compounds are formed of a nature to remain wholly or
partly undissolved in the tank, I lixiviate the ore with any suitable liquid in order
to remove such compounds.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Stephen Henry Emmens in the Great Seal Patent Office on
the 14th July 1883.
STEPHEN HENRY EMMENS, of Soho Square, in the County of Middlesex, Actuary,
"IMPROVEMENTS IN THE REDUCTION OF METALLIC ORES "
My invention relates to the electrolytical reduction of metals from their ores,
and is designed to effect this by the electrolytical decomposition of solutions of the
salts of sodium, or other chemically equivalent salts, in the presence of such ores.
I may carry out my invention in the following manner. I first prepare the ore
for treatment by breaking it down to a coarse powder, or other suitable size, accord-
ing to the nature of the ore; and I then calcine it with or without the addition
of coke, culm, coal, charcoal, or other reducing material; but in some cases this
calcination may be omitted without materially interfering with the success of the
operation.
After the ore is prepared as above mentioned, place it in one compartment of
a tank of any suitable material and size, and divided into two compartments by
means of a porous diaphragm or partition. Each compartment is further provided
with an electrode or electrodes of carbon or other suitable material, and in somo
cases I disseminate granules of carbon throughout the ore, in order to obtain a
greater uniformity of action. I then fill the tank with a solution of sodic chloride,
sodic nitrate, or both combined, and I connect the electrodes with the poles of a
galvanic battery or dynamo, in such a fashion as to cause an electrical current to
How through the tank, from the ore to the opposite extremity. Nascent chlorine,
or nitric acid, or a mixture of the two, is thus evolved in the ore compartment,
and acts on the metals contained in the ore and gradually dissolves them, its action
being in some cases assisted by a jet of steam or other source of heat. At suitable
intervals the liquors are drawn off from the two compartments and are mixed
together, in which case the metals in solution are precipitated, by means of the froe
alkali derived from the electrolytic decomposition of the original salt; and then
the supernatant liquid is ready to be used again for the treatment of a fresh parcel
The ordinary method of precipitation by metallic iron or zinc may how-
ever be employed if preferred, or the metallic solution may be electrolytically
decomposed.
of ore.
I do not always employ a tank divided into compartments as above described.
I sometimes put the ore in a porous tank or casing, placed in an outer tank; and
sometimes I simply place the oro at the bottom of a tank, and fix the negativo
electrode in the supernatant fluid. In this latter case, which is specially suitable
for ores containing gold and silver, I profer to place a receiver under the negative
electrode, to catch any metallic deposit that may drop away from such electrode,
and I furthermore add some potassic cyanide or sodic hyposulphite to the working
solution, where the extraction of gold or silver is desired.
In some cases I carry the preliminary furnace reduction of the ore, to tho-extent
of producing a regulus, which I then connect up as an anode in the reduction tank,
and proceed as before mentioned.
In cases where metallic compounds are formed of a nature to romain wholly or
partly undissolved in the tank, I lixiviate the ore with any suitable liquid in order
to remove such compounds.
Having now fully described and ascertained the nature and objects of my

page_text: invention and the manner of its performance be it known that what I consider
novel and desire to protect by Letters Patent is :-
First. The alternative processes of electrolytical reduction of metals or metallic
oxides from metallic ores substantially as set forth.
Second. The employment in such processes of electrolytes capable of recomposi-
tion by the process so as to allow of repeated use, substantially as set forth.
In witness whereof I, the said Stephen Henry Emmens, have hereunto set iny
hand and seal this thirteenth day of July in the year of our Lord One thousand
eight hundred and eighty-three.
STEPHEN H EMMENS (L.S.)