Improvements in Separating, Purifying, and Analyzing Mixed Waste Acids and Apparatus therefor.
Year: 1898

page_text: Improvements in Separating, Purifying, and Analyzing Mixed Waste
Acids and Apparatus therefor.
I, JAMES SHARP, of Shirley Manor, Wyke, in the County of York, Dyer and
Chemical Manufacturer, do hereby declare the nature of this invention to be
as follows:-
In the manufacture of trinitrophenol known as picric acid, large quantities of
both sulphuric and nitric acids are employed which in the process become much
diluted, impure and of so little commercial value that large quantities of these
mixed acids have been treated as worthless products.
This invention relates to the recovery, separation, and purification of such
waste acids or by-products arising from the manufacture of picric acid and various
dyes, by distillation of same in vessels constructed as described below.
In carrying out the invention a suitable tank or vessel is constructed in which
the waste liquors are treated. This tank is provided with an inside facing of
stones, artificial stones, tiles, bricks, earthenware, glass or other suitable material
with a cement capable of resisting the action of boiling mixtures of strong acids.
The facing of the tank comprises blocks of convenient form and size, and where
necessary, a rabbet or shoulder is worked on the stone or other material so used,
to enable the tank to be covered and the joint sealed with cement. The tank is
connected with condensing towers in the usual way, and a small opening is made
in the lid or cover which is kept closed whilst working, through which it is
charged with the mixed waste acids. This small opening is also used for taking
samples for testing and drawing off by syphons when the operation is finished.
The finished product in the tank is sulphuric acid, as-brown oil of vitriol, and
is drawn off for sale.
By this construction an apparatus is produced capable of separating, purifying
and analyzing by distillation the mixed waste acids and preparing therefrom a
by-product of commercial value and importance.
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents,

page_text: Improvements in Separating, Purifying, and Analyzing Mixed Waste
Acids and Apparatus therefor.
I, JAMES SHARP, of Shirley Manor, Wyke, in the County of York, Dyer and
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 ascer-
tained in and by the following statement:
In the manufacture of trinitrophenol known as picric acid, large quantities of
both sulphuric and nitric acids are employed which in the process become much
diluted, impure and of so little commercial value that large quantities of these
mixed acids have been treated as worthless products.
This invention relates to the recovery, separation and purification of such
waste acids or by-products arising from the manufacture of picric acid and various
dyes, by distillation of same in vessels constructed as described below.
The invention will be fully described with reference to the accompanying
drawings.
Fig. 1. Front elevation of the apparatus.
Fig. 2. Transverse section of same on line x-x.
Fig. 3. Transverse section on line y―y.
Fig. 4. Plan.
Fig. 5. Sectional plan of flues.
Fig. 6. Longitudinal section.
The apparatus comprises a tank or vessel A in which the waste liquors are
treated and a furnace B with flues C and D by which the tank or vessel is heated
and maintained at the desired temperature.
The tank A is constructed of brick or stone built over the furnace and flues
the flues being covered with iron plates cover which is spread a layer of sand d.
The tank is lined with a lining à of strong sheet lead and around the sides in
the tank are placed blocks a¹ of stone, tiles, earthenware or glass or the like-
preferably tiles which are fixed over the lead with cement or other suitable
material capable of resisting the action of boiling mixture of strong acids.
The top edge of the tank A is formed of blocks E of stone, terra cotta, earthen-
ware, glass or similar material of the shape shown to cover the edges of the lead
lining a and the tiles or blocks al and prevent the boiling acid getting behind
the tiles and also to form a seating for the stone cover F to rest upon by which
the tank is enclosed these being cemented into position by acid resisting cement.
The tank A is connected in the usual way with condensing towers of ordinary
construction by the outlet pipe G and inlet apertures H with lids or covers h
provided in the top or cover F of the tank through which the charge of mixed
waste acids is introduced into the tank the apertures being kept closed while
working.
The apertures H may also be used for taking samples for testing and the residual
liquid is drawn off therethrough by syphons when the operation is finished.
In operation the waste liquor is run into the tank A and heated therein to boiling
point and maintained at that temperature sufficiently long to drive off the nitric
acid and other volatile acids which pass through the outlet pipe G to the con-
densing towers and to condense the sulphuric acid to any desired density. The
residual or finished product remaining in the tank is sulphuric acid-as brown
oil of vitriol which is drawn off for use or for sale.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
The apparatus for separating purifying and analyzing by distillation of mixed
waste acids and obtaining valuable by-products therefrom, substantially as
described.
WM. P. THOMPSON & Co.,
Manchester, Liverpool and London,
Patent Agents.