IMPROVEMENTS IN THE MANUFACTURE OF BI-CHROMATE OF SODA
Year: 1884

page_text: I, CHARLES STUART GORMAN, of Irvine, in the County of Ayr, North Britain,
Manufacturing Chemist do hereby declare the nature of the said invention for
"IMPROVEMENTS IN THE MANUFACTURE OF BI-CHROMATE OF SODA," to be as.
follows:
This Invention, which relates to improvements in the manufacture of Bi-Chromate
of Soda, consists in placing in a furnace a mixture of about 250 parts by weight of
Chrome iron ore, 80 parts by weight of Chloride of Sodium, 100 parts by weight
of Sulphate of Soda, and 250 parts by weight of Hydrated Lime. This mixture is'
acted upon by superheated steam at a temperature which may vary from 1000° to
about 1600° Fahrenheit. During this operation, both Hydro-chloric Acid and
Sulphurous Acid are evolved, and these are collected by conveying them to
condensers. When the reactions are complete, the mixture is withdrawn from the
furnace. It is then treated in the ordinary manner to obtain the Chromates, and
afterwards treated with Sulphuric Acid, in order to convert the Chromate into-
Bi-Chromate. The solution is then placed in coolers, and the Chloride of Sodium
and Sulphate of Soda then separate out as the solution cools. After the last
mentioned treatments, the Bi-Chromate is evaporated down to any required degree
of concentration, after, which it is further concentrated by blowing air, heated from
say 400° to about 700° Fahrenheit, into the liquid or the vessel containing it. The
resulting Bi-Chromate is then run off into metallic drums for commercial use, or it
may be run into open trays which are placed on the platforms or chains of a
travelling oven, in passing through which the Bi-Chromate is or may be evaporated
to dryness.
J. H. JOHNSON, DAY, & JOHNSON,
Petitioner's Agents,
115, St. Vincent Street, Glasgow.

page_text: I, CHARLES STUART GORMAN, of Irvine, in the County of Ayr, North Britain,
Manufacturing Chemist do hereby declare the nature of my invention for
IMPROVEMENTS IN THE MANUFACTURE OF BI-CHROMATE OF SODA and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This Invention which relates to improvements in the Manufacturé of Bi-Chromate
of Soda, consists in placing in a furnace a mixture of about 250 parts by weight of
Chrome iron ore, 80 parts by weight of Chloride of Sodium, 100 parts by weight of
sulphate of Soda, and 250 parts by weight of hydrated lime. This mixture is
acted upon by superheated steam at a temperature which may vary from 1000° to
about 1600° Fahrenheit.-During this operation both Hydro-chloric acid and
Sulphurous acid are evolved, and these are collected by conveying them to
Condensers. When 'the re-actions are complete; the mixture is with-drawn from the
furnace. It.is then treated in the ordinary manner to obtain the Chromates, and
afterwards treated with Sulphuric acid, in order to convert the Chromate into
Bi-chromate. The solution is then placed 'in coolers; and the chloride of Sodium
and Sulphate of Soda then separate out as the solution cools. After the last
mentioned treatments, the Bi-Chromate is evaporated down to any required degree
of concentration, after which it is further concentrated by blowing air, heated from
say 400° to about 700° Fahrenheit, into the Liquid or the vessel containing it.
resulting Bi-Chromate is.then run off into metallic drums for commercial use, or it
may be run into open trays which are placed on the platform or chains of a
travelling oven, in passing through which the Bi-Chromate is or may be evaporated
to dryness.
The
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:-
The Manufacture of Bi-Chromate of Soda in the manner hereinbefore described.