Improvements in the Reduction of Zinc Oxides.
Year: 1888

page_text: Date of Application, 12th Sept., 1888
Complete Specification Left, 11th June, 1889-Accepted. 13th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in the Reduction of Zinc Oxides.
I CHARLES ANTHONY BURGHARDT of 35 Fountain Street, in the City of Manchester,
County of Lancaster, Analytical Chemist, do hereby declare the nature of this
Invention to be as follows:-
My Invention relates to the production of metallic zinc from certain of its ores or
from oxides resulting from the treatment of zinc ores or others matters containing
zinc. For some purposes it is of great importance to obtain zine in a state of purity
that is to say free from iron manganese or other matters with which ordinary zinc is
associated. I obtain the zine by electro deposition from an alkaline zincate solution
or from a bath in which the alkaline zincate is produced during the operation. I
prepare an alkaline zincate by dissolving the zinc oxide contained in roasted zinc ore
or by dissolving zinc oxide otherwise obtained in caustic soda or potash.
In practice I have found that the solution can be more readily obtained of a
suitable strength by first melting solid caustic soda or caustic potash and then adding
to the melted alkali a suitable proportion of the zinc oxide or roasted zinc ore. I then
heat the mixture and thoroughly agitate or incorporate the matters.
When the mass
has cooled sufficiently I add sufficient water to dissolve it. If the operation has been
properly conducted a complete or nearly complete solution will be obtained. The zinc
oxide is hydrated by the action of the caustic alkali and is thereby rendered easily and
completely soluble in the presence of an excess of alkali. In place of this method
of obtaining the solution the zinc oxide might be boiled in a solution of the caustic
alkali but I have not found such a proceeding to be so suitable as the one first
described. I use the solution so prepared as a bath and obtain the pure zinc from such
bath as an electro deposit upon suitable cathodes preferring to use cathodes of pure
zinc. 1 prefer to divide the tank or cistern in which the electro deposition is conducted
into a number of compartiments or otherwise I prefer to use a series of connected
tanks or cisterns the solution being introduced at one end of the series and flowing
from one tank to the other and issuing at the other end of the series. The first tank
will contain the strongest solution and as the solution parts with its zinc it passes on
from one tank to another so that if the tanks are suitable in number and capacity the
effluent solution will have completely or almost entirely parted with its zinc. The
effluent liquid may be concentrated to the solid state or to a suitable condition to be
again used in the production of the solution of zinc oxide.
Dated this 114k
1000
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.
COMPLETE SPECIFICATION.
Improvements in the Reduction of Zinc Oxides.
I CHARLES ANTHONY BURGHARDT of 35 Fountain Street, in the City of Manchester,
County of Lancaster, Analytical Chemist, do hereby declare the nature of this Inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement, that is to say :-
My Invention relates to the production of metallic zinc from certain of its ores or
from oxides resulting from the treatment of zinc ores or other matters containing
zinc and consists of an improvement in a former invention for which I have made
application for Letters Patent such application bearing the number 9886 of the
year 18SS. The object of such former invention was principally to obtain zinc in a
state of purity that is to say free from iron manganese or other matters with which
ordinary zinc is associated.

page_text: In the carrying into effect of my former invention I obtain the zinc by electro
deposition from an alkaline zincate solution or from a bath in which the alkaline
zincate is produced during the operation,.I prepare an alkaline zincate by dissolving
the zinc oxide contained in roasted zinc ore or by dissolving zinc oxide otherwise
obtained in caustic soda or potash.
In practice I have found that the solution can be more readily obtained of a suitable
strength by first melting caustic soda or potash and then adding to the melted alkali a
suitable proportion of the zinc oxide or roasted zinc ore.
According to my present invention I melt solid caustic soda or caustic potash in a
suitable pot or vessel. When completely melted I add roasted ore which has been
ground or disintegrated or otherwise reduced to a powder or suitably fine state of
subdivision. In practice I have found that the ore powder may be added to the melted
caustic alkali in the proportion of about 112 pounds of the powder to 224 pounds of
caustic alkali weighed before melting. After the addition of the powder to the melted
caustic alkali I heat the mixture and thoroughly agitate or incorporate the matters.
When the mass has cooled sufficiently I add sufficient water to dissolve it. If the
operation has been properly conducted a complete or partly complete solution will be
obtained. The zinc oxide is hydrated by the action of the caustic alkali and is thereby
rendered easily and completely soluble in the presence of an excess of alkali. I use
the solution so prepared as a bath from which the zinc can be obtained by electro
deposition in accordance with my said former invention or in any suitable manner.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is :-
(1) The process for the preparation of a bath solution from which pure zinc can
be obtained by electro deposition substantially as set forth.
(2) The process for the recovery of zinc from its oxides or ore consisting in the
addition of the oxide or roasted powdered ore .containing oxide of zinc into melted
caustic soda or potash the heating of the mixture the lixiviation of the resulting mass
and the use of the obtained solution as a bath in the obtainment of pure zinc by electro
deposition substantially as set forth.
Dated this Sth day of June 1889
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.