Improvements in the Manufacture of Silicates of Sodium and Potassium, of Nitrio and Sulphuric Acids, and of Caustic Soda and Potash..
Year: 1896

page_text: Date of Application, 4th Feb., 1896
Complete Specification Left, 4th Nov., 1896-Accepted; 23rd Jan., 1897.
PROV
NAL
UATION
Improvements in the Manufacture of Silicates of Sodium and
Potassium, of Nitrio and Sulphuric Acids, and of Caustic
Soda and Potash..
I, WILLIAM GARROWAY, of Netherfield Chemical Works, Duke Street, in the
City of the County of Glasgow, North Britain, Manufacturing Chemist, do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in the manufacture of sodium and potassium
silicates and of nitric and sulphuric acids, and has for its object also the manufacture
of caustic soda and potash in a cheap and efficient manner without the use of any
expensive reagent, and at the same time to obtain nitric and nitrous acids. For
this purpose I take nitrate of soda or potash and ground sand or flint and heat them
in a suitable furnace or retort to redness (if necessary over or through which
superheated steam is passed). Nitric acid is evolved and may be condensed by
any known means or sent direct from the retort in which it is evolved, to the
chambers for the manufacture of vitriol.
The retort or vessel, when the process is employed in connection with the
production of vitriol may be advantageously placed on the pyrites burners in order
to utilize their heat.
The mixture of silicate of soda or potash that remains in the retorts is
withdrawn when the action has ceased, and treated with water and steam: while
some sand remains insoluble, the silicate of soda or potash dissolves and forms a
solution and may be either disposed of directly as silicate of soda after boiling
down or concentrating to the desired strength, or the silicate of soda may be
treated with lime to precipitate the silica, while the caustic soda or potash remains
in solution and may be treated by known means. The insoluble silicate can be
dried and treated for cement manufacture.
In carrying out my invention I proceed as follows:-
I mix together two hundred to three hundred parts by weight or thereby of
silica or sand (ground) to one hundred parts by weight or thereby of nitrate of
soda and place this mixture in a retort or vessel preferably of cast iron, which in
the case of the manufacture of vitriol is placed or built in the kiln and heated by
the flame of burning pyrites or sulphur passing over and around it. I then pass
superheated steam through the hot charge (and a little hot air when required),
which effects the decomposition, nitric acid being evolved, which is conducted
directly into the vitriol chambers or Glover towers, or it is condensed for sale or
treated in any other known way. The mixture of silicate of soda and sand
remaining in the retort is now withdrawn, treated with water and steam if
necessary by which silicate of soda is obtained in solution.
1906
JOHNSONS,
115 St. Vincent Street, Glasgow, Petitioner's Agents.

page_text: Improvements in the Manufacture of Silicates of Sodium and
Potassium, of Nitric and Sulphuric Aoids, and of Caustic
Soda and Potash.
I WILLIAM GARROWAY, Manufacturing Chemist of Netherfield Chemical
Works, Duke Street, Glasgow, in the County of Lanark, Scotland, 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:―
This invention relates to improvements in the manufacture of silicates of sodium
and potassium and of nitric and sulphuric acids, and it has also for its object the
manufacture of caustic soda and caustic potash, in a cheap and efficient manner,
and without the use of any expensive reagent or material.
U
For this purpose I take nitrate of soda or of potash with ground sand or flint
and heat them in a suitable furnace or retort, (over which or through which I pass
superheated steam and hot air) silicate of the alkaline base is formed, while nitric
acid is evolved and may be condensed by any known means, or sent direct, from
the vessel in which it is evolved, to the chamber for the manufacture of vitriol.
The retort or vessel inay be heated by any ordinary means, but when the process is
employed in connection with the production of vitriol, it may be advantageously
placed on the pyrites burners in order to utilise the heat.
When the action has ceased the silicate of soda or of potash that remains in the
retort is withdrawn and is treated with water and steam. Some sand or silica
remains insoluble, but the silicate of soda or potash dissolves and forms a solution,
which may either be disposed of directly or, after being boiled down or concentrated
to the desired strength, be employed for the manufacture of soap powders, or in
the process of rectifying mineral oil. Or the silicate of soda or potash may be
treated with lime, to precipitate the silica, while the caustic soda or potash
remains in solution, and may be treated by any known means; and the insoluble
silicate may be dried and treated for the manufacture of cement.
In carrying out my invention I proceed as follows:-
I mix together from one hundred to two hundred parts by weight of sand or
ground flint with one hundred parts by weight, or thereby, of nitrate of soda, or its
equivalent of nitrate of potash, and place this mixture in a retort or vessel,
preferably of cast iron, which, in the case of the manufacture of vitriol, is built in
the kiln, and is heated by the flames or heat of the burning pyrites or sulphur
passing over or around it. I then pass superheated steam through the hot charge
(and a little hot air when required) which effects the decomposition, nitric acid
being evolved, which is conducted directly into the vitriol chambers or the
Glover towers, or it is condensed for sale or treated in any known way. The
mixture of silicate of soda or of potash and sand, remaining in the retort, is
now withdrawn, treated with water and steam, by which the silicate is obtained in
solution.
In carrying out my process, when it is employed in connection with the
manufacture of vitriol or sulphuric acid, the apparatus and plant I employ will be
readily understood from the accompanying drawings and the following
description :-
Figure 1 is an elevation shewn partly in section.
Figure 2 is a cross section.

page_text: eading to sulphuric acid chambers or Glover tower
nitric acid thereto, E E drawing off or discharging doors. F is the superheated
steam supply pipe, G, G are the pyrites or sulphur burners. H is the Glover
tower.
Two retorts may be used for a set of six chambers, but that will of course
depend on the capacity of both the retorts and the chambers. The one retort may
be opened and be charged or discharged without in the least interfering with the
process going on in the other.
When the process is not intended to be applied in connection with the manu-
facture of sulphuric acid, the retorts may be heated by the combustion of ordinary
fuel, in any suitable furnace, or in any well known manner.
Having now particularly described and ascertained the nature of my said
invention and the means by which I carry it out, I declare that what I
claim is :-
1st. The production of silicate of soda and of potash and of nitric acid by
heating a mixture of silica, in the form of ground sand or flint, with nitrate of soda
or of potash, with superheated steam, as herein before described.
2nd. The employment in the vitriol chamber or Glover tower, of nitric acid
prepared by heating a mixture of silica, in the form of sand or flint, with nitrate
0 of soda or of potash, as herein before described.
3rd. The production of caustic soda or caustic potash by treating the silicate
of soda or of potash obtained in the aforesaid processes, with lime, as hereinbefore
described.
of November 1000
ONE
of Nov
JOHNSONS,
115 St. Vincent Street, Glasgow, Applicant's Agents.