A Process for Extraction of Antimony from its Ores, and Separation of other Metals therefrom.
Year: 1891

page_text: Date of Application, 15th May, 1891
Complete Specification Left, 8th Feb., 1892-Accepted, 12th Mar., 1892
PROVISIONAL.SPECIFICATION.
A Process for Extraction of Antimony from its Ores, and Separation
of other Metals therefrom.
I, ARTHUR WILLIAM WARWICK, of the Phoenix Test Works, Battersea in the
County of Surrey, Metallurgical Chemist, do hereby declare the nature of this
invention to be as follows:-
My invention relates to a wet process for the extraction of antimony from its
ores and for separation of other metals therefrom, this process being more
especially applicable to those ores which contain such metals as render the refining
of antimony difficult.
I agitate the finely crushed ore with a hot solution of a sulphide or hydrated
oxide of an alkaline or alkaline earth metal. The thin mud thus produced,
after boiling for several hours is passed through a filtering apparatus, and the
clear liquid is treated with sulphuric or hydrochloric acid which precipitates_the
antimony sulphide, which is then filtered from the mother liquor and dried. This
antimony sulphide is then roasted to free it as much as possible from sulphur and
arsenic, and reduced in the usual way to the metallic state.
By the process above described the antimony is separated from most of the
metals which are usually associated with it in its ores, these metals or their com-
pounds being retained in the mud residue left after first filtering, from which they
can be extracted by known methods.
Dated this 15th day of May 1891.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
A Process for Extraction of Antimony from its Ores, and Separation
of other Metals therefrom.
I, ARTHUR WILLIAM WARWICK of the Phoenix Test Works, Battersea in the
County of Surrey, Metallurgical Chemist, 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:—
My invention relates to a wet process for the extraction of antimony from its
ores and for separation of other metals therefrom, this process being more especially
applicable to those ores which contain such metals as render the refining of antimony
difficult.
I agitate the finely crushed ore with a hot solution of a sulphide or hydrated
oxide of an alkaline or alkaline earth metal such for example as sodium sulphide
or hydrate. The thin mud thus produced, after agitation and boiling for several
hours is passed through a filtering apparatus, and the clear liquid, which contains
all the antimony, is treated with sulphuric or hydrochloric acid, preferably
sulphuric acid, which precipitates the antimony sulphide as golden sulphide of
antimony, if a sulphide ore be treated. This settles as a heavy precipitate from
the mother liquor which can be run off and filtered. This antimony sulphide is
then dried and reduced by the usual known methods to the metallic state.
When acids are not available for treatment as above described of the filtered
liquid, an electrical current of low tension may be passed through the liquid,
causing deposit of metallic antimony.
As an example, I may describe the process applied to the mineral known as
D
827

page_text: Jamesonite containing lead and antimony sulphides, and usually some silver.
crush this mineral to a powder that will pass through a sieve having 900 holes to
the square inch, and to each ton of the powder add Scwt. of sodium sulphide and
enough water to form a very thin sludge, which, after heating and agitating for
3 to 4 hours, I pass through a filter. The pulp remaining in the filter is washed
several times with water, then dried and treated in the usual way for recovery of
lead and silver. The antimony solution obtained from the filter is treated with
about 8 cwt. of commercial hydrochloric acid, or, more cheaply, with "tower
acids." The gases evolved by the acid treatment are passed through milk of lime,
whereby calcium sulphide is produced in the solution rendering it capable of being
used to extract the antimony. The antimony sulphide is then dried and reduced
to the metallic state in a reverberatory furnace or crucibles.
Instead of using
acids as above described for treating the solution from the filter, an electric current
of low tension may be passed through it.
For treating a gold ore containing a small proportion such as 10 per cent. of
antimony, the crushed ore may be mixed with about 13 per cent. of sodium sulphide,
heated to about 200° F. and agitated for 3 to 4 hours. The sludge is allowed
partially to settle, and the liquor run off is treated as the filtered solution in the
previous example, whilst the settled mud is washed and treated for recovery of the
gold by amalgamation or otherwise. From these examples it may be understood
that, by the process above described, the antimony is separated from most of the
metals which are usually associated with it in its ores, these metals or their com-
pounds being retained in the mud residue left after first filtering or settling, from
which they can be extracted by known methods.
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:
The herein described process for extraction of antimony from its ores and
separation of other metals therefrom, by heating and agitating the finely crushed
ore with solution of alkaline sulphide or hydrate, filtering, acidifying the filtered
liquid and treating the precipitated antimony sulphide for recovery of the
antimony.
Deted this 8th dox of February 1800
ABEL & IMRAY,
Agents for the Applicant.