Improvements in the Elimination of the Oxides of Zinc, Iron, and Copper from Cobalt-oxide, and Apparatus therefor.
Year: 1893

page_text: Date of Application, 27th Dec., 1893
Complete Specification Left, 4th June, 1894-Accepted, 14th July, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Elimination of the Oxides of Zinc, Iron, and
Copper from Cobalt-oxide, and Apparatus therefor.
We, ERNST AUGUST EMANUEL WEINBERG, of Domnarfvet, near Falun,
Engineer, ROBERT CARRICK, of Gefle, British Vice Consul, and JOHAN GUSTAF
JOHANSON, of Gefle, Accountant, all in the Kingdom of Sweden, do hereby declare
the nature of this invention to be as follows:-
This invention relates to an improved process and apparatus for the elimination
of the oxides of zinc, iron and copper from cobalt-oxide.
According to our invention the unrefined or impure cobalt-oxide, having been
well mixed with muriatic acid of a specific gravity of say 1-12 to 1-19, until the
whole mass is of the consistency of a thick pulp, is placed in a fire-brick oven or
muffle to which atmosphere has free ingress and egress so that it can come into
contact with the materials during the operation. In this oven or muffle the mass is
heated to a red heat and energetically kept in motion at the same time.
Through the combined effect of the muriatic acid and the heat a portion of the
cobalt-oxide is transformed into chloride of cobalt, and the oxides of zinc, iron and
copper disappear as volatile gases. The temperature being still further increased,
the chloride of cobalt returns to cobalt-oxide of a dark blue colour.
The product can be varied and improved if a flux be added to the muriatic acid,
at the time the latter is mixed with the unrefined cobalt-oxide, and the whole
treated as above described. The result will be a still purer cobalt-oxide of a metallic
glittering grey colour.
The quantity of muriatic acid required depends on the percentage of zinc, iron
and copper oxides to be eliminated. If the ore contains, for example, 10 to 12%
of the oxides referred to, the proportion of muriatic acid required will be from
25. to 40%; the quantity being increased in proportion to the impurity of the ore
operated on.
1
1000
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in the Elimination of the Oxides of Zinc, Iron, and
Copper from Cobalt-oxide, and Apparatus therefor.
We, ERNST AUGUST EMANUEL WEINBERG, of Domnarfvet, near Falun,
Engineer, ROBERT CARRICK, of Gefle, British Vice Consul, and JOHAN GUSTAF
JOHANSON, of Gefle, Accountant, all in the Kingdom of Sweden, 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 an improved process and apparatus for the elimination
of the oxides of zinc, iron and copper from cobalt-oxide, by the use of muriatic
acid.
In carrying out our invention the unrefined or impure cobalt-oxide, to be treated,
having been first washed in boiling water to free it from alkali salts, and dried,
crushed and sifted through a 50 mesh sieve is mixed with about 40 per cent. of raw
muriatic acid of a specific gravity of, say, 1.19 until the whole mass is of the

page_text: consistency of a thick pulp or paste. This mass is then placed in a fire-brick
muffle or oven, previously heated to a temperature of about 900 degrees centigrade.
The oxide, after having been placed in the muffle or oven, must be energetically
kept in motion by means of an iron bar, or other suitable implement, care being
taken that the atmosphere has free ingress and egress so that it can come into
contact with the materials in the oven during the process.
The before mentioned temperature of the oven is kept up until a sample of the
cobalt-oxide taken therefrom, shows a trace of soluble chloride of cobalt, after
being boiled in water, this being usually the case after an interval of about 8 to
10 hours.
Under the combined action of the muriatic acid and the heat, the oxides are
transformed into chlorides, all of which being volatile, with the exception of the
chloride of cobalt, pass off leaving the latter intact. The temperature of the oven
is then further increased to about 1150 degrees centigrade, when the chloride of
cobalt is transformed into cobalt-oxide of a deep dark blue colour. This, after
being washed in boiling water, dried and pulverized, is ready for the market.
If 25% of rye meal or other suitable flux, be added to the muriatic acid, at the
time the latter is being mixed with the impure oxides, and the whole treated as
above described a still purer grey cobalt oxide, almost free from iron, copper, zinc
and arsenical impurities, is obtained.
In the accompanying drawing,
Figure 1 is a view of half in elevation and half in section, and,
Figure 2 a transverse section of a muffle or oven which we have found suitable
for carrying out our invention.
a is a furnace for heating the ovens is a passage for the gases from the furnace
to the chimney, c, c, e are the ovens or chambers in which the oxides are treated;
and d is a passage through which the volatile gases escape into the chimney.
e, e, e are doors or dampers which are closed while the ovens are being
heated, but which must always be open when the process of refining the cobalt
oxide is in progress.
The arrows in Figure 1 indicate the direction in which the gases pass from the
furnace to the chimney and the arrows in Figure 2 indicate the direction of the
air-currents when admitted to the ovens through the doors or dampers e.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
:-
1. The process for the elimination of the oxides of zinc, iron and copper from
cobalt-oxide consisting in mixing the oxide with raw muriatic acid in about the
proportion named, heating the mixture at a certain temperature until the oxides
become transformed into chlorides (all of which being volatile except the chloride
of cobalt pass off) and then increasing the temperature to such an extent that the
chloride of cobalt is transformed into cobalt-oxide, substantially as set forth.
2. The use for the elimination of the oxides of zinc, iron and copper from cobalt-
oxide in the manner hereinbefore described of a muffle or oven constructed and
arranged substantially as hereinbefore described and illustrated in the accompanying
drawing.
1004
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.