IMPROVEMENTS IN THE TREATMENT OF ORES CONTAINING NICKEL
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN THE
TREATMENT OF ORES CONTAINING NICKEL." A communication from abroad by
Hugues Antoine Paul Christofle and Henry Charles Bouilhet, both of Paris,
in the Republic of France.
aled the 11th August 1876, and dated the 17th June 1876.
OMPLETE SPECIFICATION filed by tho said John Henry Johnson at the
Office of the Commissioners of Patents on the 17th June 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
entleman. "IMPROVEMENTS IN THE TREATMENT OF ORES CONTAINING NICKEL."
communication from abroad by Hugues Antoine Paul Christofle and Henry
harles Bouilhet, both of Paris, in the Republic of France.
This Invention relates more particularly to the treatment of nickel ores, such for
xample, as those which occur in New Caledonia, such ores consisting of hydro-
licates of nickel and of magnesia containing varying quantities of iron and
lumina.
The analysis of samples of these ores has given the following average result,
COMPLETE SPECIFICATION filed by tho said John Henry Johnson at the
Office of the Commissioners of Patents on the 17th June 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE TREATMENT OF ORES CONTAINING NICKEL."
4 communication from abroad by Hugues Antoine Paul Christofle and Henry
Charles Bouilhet, both of Paris, in the Republic of France.
This Invention relates more particularly to the treatment of nickel ores, such for
example, as those which occur in New Caledonia, such ores consisting of hydro-
silicates of nickel and of magnesia containing varying quantities of iron and
alumina.
The analysis of samples of these ores has given the following average result,
videlicet:
Water
Silex
Peroxide of iron
Protoxide of nickel
Magnesia
Lime
Chlorides
-
21.60
37.60
6.60
18.66
15°
traces
0.40
99-86
The peculiarity of these ores which distinguishes them from the ores hitherto
treated in Europe consists in their containing neither sulphur nor arsenic, but a
remarkable quantity of magnesia in varying proportions; the total weight of the
magnesia and of the nickel is however almost invariably about the same, these
two bases by reason of the laws of isomorphism being substituted one for the
other.

page_text: The nickel ores of New Caledonia contain considerable quantities of iron in the
state of silicate and of oxides. The iron is not combined with the nickel, but
forms a separate combination either stratified in alternate layers with the silicate of
nickel, or diffused in the mass and without apparent order, but so as to be casily
recognised by the ochrous color of the ore.
The mode of treating the ore by melting it directly after having pulverised it is
open to the objection that the whole of the iron contained in the ore forms a
combination with the (fonte de nickel), or the fused nickel from which it is very
difficult to eliminate it. In fact in order to effect this elimination it is necessary
either to resort to a puddling process at a high temperature, which in order to
scarify the iron causes considerable quantities of nickel to pass off in the scoria
and produces great and costly waste, or to employ a process of refining by solution,
which is as long and costly as if the whole of the ore were subjected to the direct
action of acids.
According to this Invention the chemical and physical constitution of the ore is
made available in order to eliminate the iron which it contains by a combined
method of treatment by a wet process previously to treating the nickel ore by the
dry process.
In effecting a separation of the iron by means of the wet process, the ores which
are obtained in masses of varying sizes are first washed in any suitable mechanical
washing apparatus, in order to cleanse them from the dust and earths which
contain nothing but iron and a very little nickel which are called (Bone's A
hereafter described; then after roughly sorting them putting aside all the pieces
which are wholly free from iron ore to be treated as herein-after described, the
remaining ore is reduced by stamping to an average size, say, for example, not
exceeding the size of a hazel nut.
As the iron ore is reduced to powder more easily than the nickel ore, a second
washing yields a fresh quantity of ferruginous earths containing a little more nickel
than the first mentioned called Bone's B, and hereafter referred to.
The ore after having been again washed and sorted if necessary, is then pulverized
completely and treated in suitable apparatus by an acid, such, for example, as the
hydrochloric acid of commerce.
The silicates and oxides of iron are first attacked and dissolve before the silicate
of nickel, thus enabling the iron to be separated from the nickel in this first
treatment by a wet process. This operation may be carried out with or without
heat in any suitable tanks or receptacles of wood, earthenware, porcelain, glass, or
the like.
By means of a methodical lixiviation with hydrochloric acid in suitable apparatus
by the customary systems, the iron is dissolved out by means of the acid. The
solutions thus obtained contain the whole of the iron, the magnesia, and a certain
quantity of nickel.
As soon as the pulverized ore loses its ochrous tint, and the silicate of nickel
appears with its beautiful green colour, the operation is to be stopped and the ore
tested to ascertain if it still contains iron. If it is found to contain iron it is to be
again digested with fresh acid, care being taken not to dissolve too much of the
nickel. If the ore is then found not to contain any more or but a small quantity of
iron it is washed and dried, and the water in which it has been washed is put aside
to be treated in order to separate the nickel which it contains. The acids con-
taining the iron and a certain quantity of nickel which was necessarily dissolved
are afterwards employed to act upon the (Bones) A and B, and thus serve to dissolve
them.
After the process of solution is completed the solution will contain iron, nickel,
and magnesia, and they are treated in such manner as to separate the iron and the
magnesia, and to collect the nickel by one of the processes of treatment herein-after
described; other acids than hydrochloric acid may also be employed for the purpose
of separating iron from the nickel contained in Caledonian ores in order to enable
the ores to be subsequently treated by the dry process, for example, tartaric acid,

page_text: acetic acid, or oxalic acid may be used, providing that the salt of iron obtained is
soluble; in this case oxalic acid is preferred by reason of its possessing the advantage
of forming at the same time an insoluble salt of nickel, and in consequence of the
whole of the nickel remaining in the ore, which result does not take place when
hydrochloric acid is employed.
When oxalic acid is employed the operation is carried out in the following
manner: The ore reduced to a fine powder is treated hot, and in sufficient
quantities with a concentrated solution of oxalic acid in suitable vessels; after
heating for several hours when it has been ascertained that the insoluble powder
does not contain any more iron, the liquid is run off and the ore washed. The
waters containing oxalate of iron, magnesia, and oxalic acid in excess are afterwards
treated by milk of lime. The oxalate of lime produced is digested with sulphuric
acid, in order to revivify the oxalic acid, which may then be re-utilized in the
manufacture.
As oxalic acid is formed when an organic substance is heated in presence of
matter capable of imparting oxygen to it, the result will be similar whether the
acid be prepared beforehand or obtained by the reaction of the elements, which
serve for its preparation in presence of the ore.
In carrying out the subsequent dry process for the treatment of the ore, the ore
after having been washed and dried and re-united with the ore resulting from the
first sorting, is afterwards mixed with the quantity of pulverized wood, charcoal,
and flux, suitable for producing the reduction and fusion of the metal, and a very
fluid scoria.
The flux which has been found to give the best result consists of a mixture of
carbonate of soda and carbonate of lime, the proportions of which may be varied
according to the nature of the ore and the amount of silex and magnesia which it
contains; it possesses moreover the advantage of scorifying any iron which may
still remain.
Preliminary trials will indicate the proportions to be employed; other fluxes may
however be used, such for example, as fluor spar, borax, vitreous salts, and other
known fluxes, with a similar result.
The ore thoroughly mixed with charcoal and flux is placed in successive charges
and highly heated, either in a crucible heated by itself in an air furnace, or in
crucibles heated in a special furnace, or in a reverberatory furnace heated directly
by coal or a gas furnace on one of the known systems, such, for example, as
Ponsard's, Siemens', or others, or in any other suitable apparatus by running off the
scoria from time to time, or by skimming it off with a ladle, the progress of the
operation may be ascertained and fresh quantities of mixture of ores and flux may
be added, thus increasing the amount of product obtained from the operation.
The result is commercial nickel, which may be run into ingots, shot, and the
like.
This metal may be utilized directly for producing the commercial alloys with,
say, 80 and 50 per cent. of copper or other metal; for this purpose it is sufficient
to remelt it with the proper quantity of copper or other metal, the proportions of
fluxes which have been found most successful being those which constitute bottle
glass, a vitreous scoria is obtained, the average composition of which is as
follows:-

page_text: remelting it in ordinary glass makers crucibles, and by a suitable treatment
excellent bottle glass may be obtained, thus rendering valuable this refuse of the
manufacture.
The proportions of silex, soda, lime, and magnesia may vary without making any
perceptible alteration in the quality of the glass. In all cases as the scoria is
completely pulverized in order to extract any nickel which it may contain, its
composition may be ascertained by a preliminary analysis, and the quantities
readjusted to the normal proportions herein-before indicated.
After the preliminary process for effecting the separation of the iron (the Bones)
A and B herein-before referred to having been added to the ores which were found
to be too ferruginous to be heated by the dry process, the solution is effected in
earthen or stoneware vessels heated by a bain marie by means of hydrochloric acid
with the addition of a small quantity of nitric acid, in order to peroxidise the iron,
or of chloride of lime when the solution is completed, which becomes apparent by
the colour of the washed residue; the fluid is poured off and the residue is treated by
washing until it becomes white. The whole of the washings resulting from the
washing are then collected in large tanks of wood or other suitable material, in
which the separation of the iron is to be effected by means of carbonate of lime, as
in the known processes.
Powdered chalk is added in small quantities for the purpose of neutralizing the
acid and precipitating the iron.
When the solution is completely cleared of iron, which effect may be ascertained
by taking samples, and testing them with a reagent capable of indicating its
presence, it is allowed to settle, and the liquid is poured off.
The liquor which is poured off contains chlorides of nickel, magnesium, and
calcium.
The ferruginous and calcareous matters are set aside to be washed and the water
collected for other operations. The liquids are collected in large tanks constructed of
wood or masonry; they are then treated while cold with a solution of chloride of
lime, which precipitates a part of the nickel in the condition of black sesquioxide;
the treatment is then concluded by the addition of lime water, which continues and
effects the complete precepitation of the nickel without precipitating the magnesia.
The precipitate readily separates with facility and falls in a short time to the
bottom of the tank.
The relative proportions of chloride of lime and lime water may be varied without
inconvenience provided that the precipitate is always black, they may also be
added at option either separately or in the inverse order, but it is important that
they should act simultaneously.
The chloride of lime alone does not precipitate the whole of the nickel, the
chlorine which is evolved whilst it dissolves a part of the black precipitate leaves a
certain quantity of nickel in the liquor.
Lime water firstly precipitates the nickel and afterwards the magnesia, but it
is somewhat difficult to carry this precipitation practically into effect. The simul-
taneous employment however of chloride of lime and of lime water obviates these
objections.
Similar results may be obtained by the employment of a current of chlorine
passed directly either in the state of gas, or either generated by means of an
electric current in the liquors or otherwise, but the use of chloride of lime is
preferred.
The precipitates are first washed and are collected and dessicated, they are then
washed in boiling water in order to remove the soluble chlorides, after which they
are calcined and finally washed in water slightly acidulated with hydrochloric acid,
then pressed and moulded in cubes or other shapes, dried, and reduced in a crucible
with the addition of carbon.
In carrying out this process it is assumed that the sulphuric acid which was
contained in the hydrochloric acid of commerce, and the sulphates contained in the
water have been previously eliminated either by the preliminary action of a salt of

page_text: baryta, or by prolonged washings of the oxides of nickel, otherwise the reduced
nickel would contain sulphur.
The hydrochloric acid of commerce generally contains sulphuric acid; the waters
introduce it into the liquors; it results therefrom that the precipitates of nickel
always contain sulphates, which in presence of the carbon in the act of reduction
produce sulphur which combines with the nickel and renders it brittle. It is
therefore very necessary to wash the oxides of nickel with great care in order to
free them from sulphates. This treatment is long, delicate, and uncertain in its
results. The nickel reduced always contains a certain quantity of sulphur.
In order to effect the elimination of the sulphur according to this Invention, tho
presence of magnesia in the ore is made available by leaving a small quantity of
magnesia in the precipitate, in order to separate the sulphur by the production of
scoriæ containing magnesia and sulphur in the reducing operation.
In carrying out this process according to this Invention we proceed in the
following manner:-The ores having been pulverized and dissolved in hydrochloric
acid of commerce are treated with carbonate of lime, in order to separate the iron as
berein-before stated. The neutralized liquors are collected in large tanks constructed
of masonry, wood, or other suitable material, and are then immediately treated with
lime water. The exact quantity of lime water necessary to precipitate all the
nickel may be ascertained by a preliminary titration of the solution to be pre-
cipitated, and of the lime water. By arresting the precipitation of the nickel
before the whole has been precipitated, the magnesia is not precipitated; whereas
by precipitating the whole of the nickel, a very small quantity of magnesia is
precipitated. It is therefore easy by ascertaining beforehand by the preliminary
titration the exact quantity of lime water necessary for precepitating the whole of
the nickel, so as to obtain a precipitate containing a very small quantity of
magnesia, which is found to be the quantity sufficient to separate the sulphates in
the subsequent operations.
The lime water having been employed in sufficient quantity, and the precipitate
of oxide of nickel obtained, it is washed in several waters to cleanse it from the
soluble chlorides; it is then collected, dried, and washed with hot water in order to
remove all the soluble salts, and then washed again with a small quantity of
acidulated water. In this condition it is mixed with a suitable quantity of any
carbonaceous substance, and agglomerated in the form of cubes, cylinders, balls, and
the like, by mechanical or other means. It is then heated in crucibles, tubes,
retorts, or other known appliances in a continuous or intermittent manner in the
presence of pulverized charcoal for the purpose of effecting its reduction. The
temperature should be raised until each cube is completely fused so as to form a
drop or drops enveloped in scoria containing sulphur and magnesia, thus completely
purifying the nickel from these substances, which might have had a deleterious
effect upon it.
The nickel is separated from the scoria by stamping or any other means of
producing powerful compression or friction, then sifted and washed if necessary.
The cubes, reduced but not melted, are collected and pulverized together with
the scoria, and subsequently treated in a magneto sorter in order to separate it from
the too finely melted portions, and from the nickel which has been reduced to
powder, but not agglomerated.
A second fusion after the mechanical separation of the scoria effected with the
fluxes ordinarily employed completes the operation. The result is inetallic nickel
melted in buttons or shot containing some few hundredths per cent. of carbon and
perfectly free from sulphur.
This metal may be easily hammered; it may be melted to form commercial alloys
directly with from 50 to 80 per cent. or other suitable proportions of copper by
adding the customary fluxes. This operation is carried out in crucibles, rever-
beratory furnaces, cupolas, or other suitable apparatus; it may also be melted with
copper and zinc in order to form various known alloys, such, for example, as

page_text: German silver. The fusion is effected in the ordinary manner, and with the known
and usual fluxes. In these two cases the carbon is completely eliminated by the
action of the copper and of the zinc together or separately during the fusion.
When it is desired to obtain pure metal, the nickel is remelted either in the
crucible or otherwise, by treating them before running out with known decar-
burating agents, especially with the metallic oxides.
To effect decarburization I employ oxide of nickel which in decarburating leaves
nothing but nickel in the metal, but I also employ oxide of zinc in sufficient
quantity to burn the carbon contained in the nickel, and in such quantity as that
the reduced zine may be completely eliminated by volatilization at the high
temperature employed for the fusion of nickel.
The commercial alloy of nickel and, copper may also be produced by the direct
and simultaneous reduction of the two oxides. In this case the precipitated oxide
of nickel after washing with hot water, as herein-before described, is to be mixed
with a suitable quantity either of copper scales, or of oxides of copper and carbon.
aceous matter, and then agglomerated into the form of cubes, cylinders, or otherwise.
The reduction is effected in the manner herein-before described.
Lastly. In case the treatment is to be applied to ores obtained from New
Caledonia, or from any other source which do not contain magnesia in their natural
condition, and which contain sulphur, a small quantity of chloride of magnesium is
to be added before effecting the precipitation of the hydrate of nickel with lime
water, which being precipitated by the lime water in the state of magnesia, serves
in the process of reduction to produce the sulphurous scoria which purifies the
metal from the whole of the sulphates which it may contain either naturally or
accidentally, and obviates the necessity for the long and difficult washings which
are commonly employed.
I claim the application of this process for the purpose of eliminating sulphur to
nickel ores whether obtained from Caledonia or elsewhere.
I also in order to effect the separation of sulphur from ores containing nickel
employ magnesia either before the reduction of the ore or during the fusion of the
metal.
Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect,
I would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention is,-
First. Effecting the extraction of nickel from the ores herein-before mentioned or
from ores similar thereto, by firstly submitting them to a preliminary treatment
which I have called the wet process, in order to separate the iron therefrom; and
which consists in the employment of an organic or of an inorganic acid, and either
already formed or generated in a nascent state in the solution, and which acid or
acids form soluble combinations with the iron.
Second. The utilization of the silex or silica contained in the ore by the employ-
ment of a suitable flux with a view to the production of commercial vitreous
products in the manner herein-before described.
Third. The employment of chloride of lime in conjunction with lime water or of
lime water alone for effecting the precipitation of the oxide of nickel in the manner
herein-before described.
4
Fourth. The precipitation of a small quantity of magnesia in conjunction and in
combination with the last traces of nickel, so that in the presence of carbon and of
sulphates contained in the oxide of nickel, a sulphurous scoria shall be formed t
during and in the reduction of the nickel.
Fifth. The employment of magnesia in order to remove the sulphur contained in
the ores or compounds of nickel as herein-before described.
Sixth. Effecting the decarburization of nickel by the employment of oxide of
nickel, in the manner as herein-before described.

page_text: Seventh. Effecting the decarburization of nickel by the employment of oxide of
zinc in the manner as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Complete
Specification set my hand and seal, this Sixteenth day of June One thousand
eight hundred and seventy-six.
J. HENRY JOHNSON. (L.S.)