Improvements in the Process for Manufacturing Barium Oxide and Sulphide.
Year: 1898

page_text: Date of Application, 9th Dec., 1898-Accepted, 4th Mar., 1899
COMPLETE SPECIFICATION.
Improvements in the Process for Manufacturing Barium Oxide
and Sulphide.
We, CHARLES SCHENCK BRADLEY, Electrical Engineer, and CHARLES BORROWS
JACOBS, Chemist, residing respectively at Avon, in the County of Livingston, State
of New York, and at East Orange, in the County of Essex, State of New Jersey,
United States of America, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The object of the present invention is to provide an economical process for the
manufacture of soluble barium salts directly from a native ore such as barytes
(barium sulphate). The process is carried out in an electric furnace at the tem-
perature of which when barytes is mixed with sufficient carbon to reduce a part
only of the barium sulphate to barium sulphide, a double reaction takes place, a
mixed charge of barium sulphide and barium sulphate being produced in the first
part of the reaction and barium oxide and barium sulphide at a later stage of the
operation. Under this treatment the original sulphate may be converted into sixty
per cent. of barium oxide and about forty per cent. of barium sulphide with a
small proportion of unconverted sulphate, amounting to less than one per cent.,
whereas in the ordinary process the yield is about sixty per cent.
of barium sulphide and forty per cent. of unconverted sulphate. The
small proportion of insoluble sulphate may be easily separated and the
soluble salts recovered separately by the usual treatment. The operation
may be conducted in any type of electric furnace. As an example of the manner
in which the process may be carried out we may take four molecular parts of
barium sulphate and four molecular parts of carbon which react upon one another
at an early stage of the heating and produce barium sulphide and barium sulphate
as will be understood from the following reaction.
4 BaSO4+4 C= BaS+3 BaSO4+400
Under a continuance of the heating a double reaction sets in between the sulphide
thus formed and the unconverted sulphate; for example,
3 BaSO,+ BaS= 4 BaO+ 4SO,
It is not possible to convert the whole of the charge into oxide as indicated by
the last equation for the reason that the reaction first set forth takes place much
Under a continuance of the heating a double reaction sets in between the sulphide
thus formed and the unconverted sulphate; for example,
3 BaSO,+ BaS= 4 BaO+ 450,
It is not possible to convert the whole of the charge into oxide as indicated by
the last equation for the reason that the reaction first set forth takes place much
more rapidly than it will react with the unconverted sulphate, thus destroying the
relative proportions for the second reaction and leaving a certain proportion of un-
converted sulphide, amounting to about 40 per cent, as well as a small proportion
of unconverted sulphate amounting to less than one per cent. in the resulting pro-
duct; the two principal products, however, barium oxide and barium
sulphide are both soluble salts and are in a condition for convenient
separation. With a charge consisting of about 20 parts by weight of sulphate and
one of carbon, a product may be obtained containing sixty per cent. of barium

page_text: oxide and about forty per cent. of barium sulphide; these proportions being slightly
modified by a small percentage of unconverted sulphate present in the residual
product. It is evident that the treatment hereindescribed offers marked advantages
over the ordinary furnace treatment where the final product is a mixture containing
sixty per cent. of barium sulphide and forty per cont. of unconverted sulphate.
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 of making soluble barium salts consisting in subjecting to the
heat of an electric furnace a mixture of barium sulphate and carbon, substantially
as set forth.
2. The process of converting barytes into soluble barium salts consisting in
mixing it with carbon and subjecting it to the heat of an electric furnace and per-
mitting the reaction to continue until the mass is converted into barium oxide and
barium sulphide, substantially as set forth.
3. The process of making an oxide from a sulphate consisting in heating in an
electric furnace a mixture of carbon and sulphate, substantially as set forth.
4. The process of making barium oxide from barytes consisting in heating in an
electric furnace a mixture of barytes and carbon, substantially as set forth.
Dated this 8th day of December 1898.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicants.