in the Manufacture of Copper and Alkali.
Year: 1885

page_text: in the Manufacture of Copper and Alkali.
I CHARLES WIGG of Walmer Buildings Water Street Liverpool in the County
of Lancaster Manufacturing Chemist, do hereby declare the nature of the said
invention for. "IMPROVEMENTS IN THE UTILIZATION OF CERTAIN RESIDUALS
OBTAINED IN THE MANUFACTURE OF. COPPER AND ALKALI" to be as follows:-
.
The object is to provide efficient means for utilizing in the manufacture of
carbonate of soda the spent liquor obtained in the extraction of copper from its
ores by the wet process, and also the waste from the manufacture of alkali by the
Le Blanc process.
Under the first part of my invention I take spent copper liquor which consists
mainly of sulphate of soda (Na, SO) common salt (Na c!) and iron in various
forms in solution and add thereto sufficient sulphide of ammonium preferably in
solution to precipitate the iron as sulphide. The precipitate is then separated
from the mother liquor by filtration or by a hydro extractor, is dryed, and
burned in the usual pyrites burners or in any suitable furnace. The iron oxide
may be prepared for use as a pigment and the sulphurous acid given off disposed
of in any convenient manner such as in the manufacture of sulphuric acid;
or the sulphide of iron may be treated in any well known or suitable way to
obtain useful products. The mother liquor which now consists almost entirely
of sulphate of soda chloride of soda and ammonia salts in solution, is passed into
apparatus where it is subjected to the action of ammonia and carbonic acid for the
formation of carbonate of soda in any of the known methods.
Under the second part of my invention I obtain sulphide of ammonium to be
used in the treatment of spent copper liquors substantially as above set forth by
decomposing alkali waste with any suitable acid preferably hydrochloric acid and
passing the sulphuretted hydrogen evolved in contact with gaseous ammonia and
ammonia in solution, any iron and other metals being thereby precipitated as
sulphides.

page_text: in the Manufacture of Copper and ‘Alkali.
I CHARLES WIGG of Walmer Buildings Water Street Liverpool in the County
of Lancaster Manufacturing 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:―
The object is to provide efficient means for utilizing in the manufacture of
carbonate of soda the spent liquor obtained in the extraction of copper from its
ores by the wet process, and also the waste from the manufacture of alkali by the
Le Blanc process.
;
Under the first part of my invention I take spent copper liquor which consists
mainly of sulphate of soda Na, SO, common salt Na cl and iron in various forms
in solution and add thereto sufficient sulphide of ammonium, preferably in solution
to precipitate the iron as sulphide. The precipitate is then separated from the
mother liquor by filtration or by a hydro extractor, is dryed, and burned in the
usual pyrites burners or in any suitable furnace. The iron oxide may be prepared
for use as a pigment and the sulphurous acid given off disposed of in any con-
venient manner such as in the manufacture of sulphuric acid; or the sulphide of
iron may be treated in any well known or suitable way to obtain useful products.
The mother liquor which now consists almost entirely of sulphate of soda, chloride
of soda and ammonia salts and free ammonia in solution is passed into apparatus
where it is subjected to the action of ammonia and carbonic acid for the formation
of carbonate of soda in any of the known methods.
Under the second part of my invention I obtain sulphide of ammonium to be
used in the treatment of spent copper liquors substantially as above set forth by
decomposing alkali waste with any suitable acid preferably hydrochloric acid and
passing the sulphuretted hydrogen evolved in contact with gaseous ammonia or
ammonia in solution, any iron or other metals being thereby precipitated as
sulphides.
3 Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed I declare that what
I claim is
First. The utilization of the spent liquor obtained in the extraction of copper
from its ores by the wet process, and the waste from the manufacture of alkali by
the Le Blanc process substantially as herein set forth.
Second. Subjecting the spent liquor obtained in the extraction of copper by the
wet process to the action of sulphide of ammonium and separating and burning
the precipitate produced for the production of oxide of iron.
Third. Subjecting the spent liquor obtained in the extraction of copper by the
wet process to the action of sulphide of ammonium separating the mother liquor
from the precipitate produced and subjecting the said mother liquor to the action
of ammonia and carbonic acid gas for the production of carbonate of soda.

page_text: Fourth. Treating the spent liquor obtained in the extraction of copper by the
wet process substantially as set forth for the production of oxide of iron and
carbonate of soda.
Fifth. Obtaining sulphide of ammonium for use in treating spent copper liquor
as herein set forth by decomposing alkali waste with an acid and passing the
sulphuretted hydrogen evolved in contact with gaseous ammonia or ammonia in
solution.