Improvements in the Manufacture of Soda and Potash.
Year: 1890

page_text: Date of Application, 29th Jan., 1890
Complete Specification Left, 28th Nov., 1890-Accepted, 3rd Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Soda and Potash.
i
1, FRANCIS ELLERSHAUSEN, of Hebburn-on-Tyne, in the County of Northumber-
land, Gentleman, do hereby declare the nature of this invention to be as follows:-
My invention relates to the manufacture of soda and potash.
In the manufacture of soda, particularly by the process known as the Leblanc
process, it is well known that the crude soda contains a certain proportion of sulphide
of sodium the sulphur of which must be removed.
Various means have hitherto been employed for effecting the removal of the sulphur,
for instance, by adding zinc to the soda liquor or solation formed during the lixiviation,
which zinc combines with the sulphur and then precipitates as sulphide of zinc ; or
by passing currents of air through the liquor to oxidize the sulphur. These processes,
however, are disadvantageous, the first chiefly for the reason of its expense and the
fact that if an excess of zinc is introduced the whole of it will not precipitate but
remain in solution; and the second owing to the length of time necessary for its
performance, and the fact that sulphate of soda is formed.
I have found by experiment that ferrate of soda readily effects the removal of the
sulphur without any of the disadvantages above referred to, as, when the ferrate is
decomposed, the iron combines with the sulphur and precipitates in the form of
sulphide of iron while the soda enters into solution with the soda liquor. In case an
excess of ferrate of soda is introduced it is also decomposed, that portion of the iron
not entering into combination with the sulphur precipitating as oxide of iron while
the soda enters into solution with the soda liquor.
In the manufacture of potash I substitute ferrate of potash for ferrate of soda.
Dated the 20th day of Lan1800
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Soda and Potash.
I, FRANCIS ELLERSHAUSEN, of Hebburn-on-Tyne, in the County of Northumber-
land, Gentleman, 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 the manufacture of soda and potash.
In the manufacture of soda, particularly by the process known as the Leblanc
process it is well known that the crude soda contains a certain proportion of sulphide
of sodium the sulphur of which must be removed.
Various means have hitherto been employed for effecting the removal of the sulphur
for instance, by adding zinc to the soda liquor or solution formed during the lixiviation,
which zinc combines with the sulphur and then precipitates as sulphide of zinc ; or
by passing currents of air through the liquor to oxidize the sulphur. These processes,
however, are disadvantageous, the first chiefly for the reason of its expense and the
fact that if an excess of zinc is introduced the whole of it will not precipitate but
remain in solution; and the second owing to the length of time necessary for its
performance and the fact that sulpbate of soda is formed.
I have found by experiment that ferrate of soda readily effects the removal of the
sulphur without any of the disadvantages above referred to, as, when the ferrate is
decomposed the iron combines with the sulphur and precipitates in the form of sulphide
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page_text: of iron while the soda enters into solution with the soda liquor. Should an excess of
ferrate of soda be introduced it will be also decomposed, that portion of the iron not
entering into combination with the sulphur precipitating as oxide of iron while the
soda enters into solution with the soda liquor.
In the manufacture of potash I substitute ferrate of potash for ferrate of soda.
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 1
claim is :-
--
In the manufacture of soda and potash treating the crude solutions of the same
with their respective ferrates, substantially as, and for the purpose, described.
Dated the 28th day of November 1890.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.