Improvements in the Manufacture of Lead Carbonate, Ammonium Nitrate, Silicates of Sodium, and Caustic Soda.
Year: 1897

page_text: Date of Application, 30th Sept., 1897
Complete Specification Left, 7th June, 1898-Accepted, 10th Sept., 1898
Improvements in the Manufacture of Lead Carbonate, Ammonium
Nitrate, Silicates of Sodium, and Caustic Soda.
I, WILLIAM GARROWAY, of Netherfield, in the County of Lanark, N.B., Chemical
Manufacturer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in the manufacture of carbonate of lead
(white lead), ammonium nitrate, silicates of sodium and caustic soda, in order to
effect the manufacture in a cheap and efficient manner, without the use of any
expensive reagent or material.
-
I do not confine myself to any particular construction or details of apparatus
used, so long as they accomplish the results herein specified that is to say:
I produce a constant stream of nitric acid by the action of silica upon nitrate of
soda in a suitably constructed furnace or mechanical retort, heated to the requisite
temperature, with superheated steam, in a manner analogous to that which I have
described in the Specification of my Patent No. 2489/96.
The nitric acid thus produced I lead into earthenware pipes or towers, at some
point in which I interpose scrap lead or litharge. The nitric acid acting directly
upon a portion of the metal, dissolves it, forming a solution of lead nitrate. This
is first treated with ammonia, and through which there passes ammonia vapours
and a current or stream of carbonic acid gas, to precipitate the lead as carbonate
or white lead. This insoluble white lead precipitate is then collected and merely
requires washing and drying at a suitable temperature to be fit for use.
The solution of pure nitrate of ammonia is run off and evaporated to obtain the
crystalline salt.
100%
Improvements in the Manufacture of Lead Carbonate, Ammonium
Nitrate, Silicates of Sodium, and Caustic Soda.
I, WILLIAM GARROWAY, of Netherfield, in the County of Lanark, N.B., Chemical
Manufacturer, 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 carbonate of lead

page_text: (white lead) ammonium nitrate, and it has also for its object the manufacture of
silicate of sodium, and without the use of any expensive reagent or material:-
I do not confine myself to any particular construction or details of apparatus
used. so long as they accomplish the results herein specified that is to say:-
I produce a constant stream of nitric acid by the action of silica with super-
heated steam upon nitrate of soda, heated to the requisite temperature, in a
suitably constructed furnace or retort, in a manner analogous to that which I
have described in the Specification of my Patent No. 2489% and also of my
Patent No. 706697.
The residue in the retort, vessel, or furnace, which remains after the nitric
acid has been evolved, consists of silicate of soda, which may be sold without
further treatment to glass manufacturers, or it may be dissolved in water, and sold
or employed for calico printers use, and for other purposes, or it may be converted
into caustic soda by treating it as in this process with lime, by which a strong
solution of caustic soda is obtained, and silicate of lime, a useful cement, is
separated in the insoluble condition.
The nitric acid thus produced I lead into earthenware pipes or stone towers-
at some point in which I interpose scrap lead or litharge. The nitric acid acting
directly upon a portion of this metal dissolves it, forming a solution of lead nitrate.
This is first treated with ammonia until the liquid is neutral or nearly so, and the
lead is then precipitated (under pressure) from the solution with ammonia &
carbonic acid or with ammonium carbonate as lead carbonate and the solution of
the ammonium nitrate thus formed is drawn off, and evaporated to obtain the
solid salt. Or the lead carbonate may be precipitated from a solution of the lead
nitrate, by means of ammonium carbonate, obtained by decomposing sulphate of
ammonia in a suitable vessel or retort with barium carbonate. The white lead
is then washed to free it from the nitrates, dried and treated in the process for
manufacture of paints by any known means.
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
1. The production of silicate of soda and of nitric acid by heating a mixture of
silica in the form of sand or ground flint, with nitrate of soda in an atmosphere
of superheated steam in a manner analogous to that which I have described in
my Patent No. 2489, A.D. 1896 and in my Patent No. 7066 A.D. 1897.
2. The production of lead nitrate by dissolving lead scrap or litharge in hot
nitric acid as hereinbefore described.
3. The process for producing nitrate of ammonia and lead carbonate by neutral-
izing and treating the lead nitrate liquor with ammonia & precipitating the lead
as carbonate of lead (under pressure) with ammonia and carbonic acid or with
ammonium carbonate for the production of nitrate of ammonia, in a manner sub-
stantially as herein before described.
4. The process for producing lead carbonate from a solution of lead nitrate by
decomposing the sulphate of ammonia in a suitable vessel or retort with barium
carbonate in a manner substantially as herein before described.
5. The production of caustic soda by treating the silicate of soda obtained in
the aforesaid processes, with lime, as herein before described.
Dated this 4th day of June 1898.
JOHNSONS,
Petitioner's Agents, 115, St. Vincent Street, Glasgow.