IMPROVED PROCESSES AND APPARATUS FOR SEPARATING TIN FROM TINNERS' WASTE.
Year: 1873

page_text: LETTERS PATENT to George Haseltine, of the "International Patent
Office," Southampton Buildings, London, "Doctor of Laws," for
the Invention of “IMPROVED PROCESSES AND APPARATUS FOR SEPARATING
TIN FROM TINNERS' WASTE.' -A communication from abroad by Pierre
"
-
De Peyster Ricketts, of the City and State of New York, United
States of America, Mining Engineer.
Sealed the 30th January 1874, and dated the 10th December 1873.
COMPLETE SPECIFICATION filed by the said George Haseltine at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 10th December 1873, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the International Patent Office," Southampton Build-
ings, London, Doctor of Laws, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVED PROCESSES
AND APPARATUS FOR SEPARATING TIN FROM TINNERS' WASTE," and have
petitioned Her Majesty to grant unto me, my executors, administrators,

page_text: and assigns, Her Royal Letters Patent for the same, and have made
solemn Declaration that it has been communicated to me from abroad
by Pierre De Peyster Ricketts, of the City and State of New York,
United States of America, Mining Engineer.
NOW KNOW YE, that I, the said George Haseltine, do hereby declare t
that the following Complete Specification, under my hand and seal,
fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, reference being had to the accompanying Drawing forming
a part of this Specification :-
The first part of this Invention relates to certain improvements in the
process of separating tin from iron in tinners' clippings. The said
improvements consist,-
]
First. In treating the tin seraps or tinners' clippings, first in
bydrochloric acid of 20° Baumé, till the bath gets exhausted, then 1
gradually adding to the latter nitric acid of 40° Baumé, in conjunction
with a concentrated solution of chlorate of potash or the same in powder
not exceeding a certain per centage herein-after specified.
Second. In treating tinners' clippings with hydrochloric acid, until
about two-thirds of the tin upon the surface is dissolved therefrom, then a
introducing the same in a bath of hydrochloric acid, nitric acid, and
chlorate of potash until the remainder of the tin is dissolved.
The advantages to be derived from the first named process will be
apparent from the following observations:-By using hydrochloric acid
without the subsequent addition of the chemicals mentioned, one 2
thousand pounds would have to be used for the cleaning of two thousand
pounds of scraps, there being generally as much iron dissolved by the
acid as there is tin on the iron. By adding however from two to three
per cent. of nitric acid, and from one to one and a half per cent. of
chlorate of potash (of the amount of hydrochloric acid) to the bath, a
when the same has become exhausted, five hundred pounds of
hydrochloric acid will suffice to treat two thousand pounds of scraps.
This fact is to be attributed to the circumstance that the oxide
(protoxide of tin) produced by the action of nitric acid, is more readily
soluble in weak hydrochloric acid than metallic tin is, but other reactions
will also take place and would produce a precipitate of hydrated oxide of

page_text: tin, which would be lost in the process, since it is not soluble in acids.
But the tin ought to be precipated from its solution in a metallic state,
in which state it would mingle with the hydrated oxide. Now this latter
as is well known requires a high heat to be reduced, both therefore could
not be worked up together. These reactions however do not take place
when chlorate of potash is added in conjunction with nitric acid. Free
chlorine will be evolved abundantly, chloride of ammonium will be
formed by combination with the ammonia formed by the action of the
nitric acid, and the precipitation of hydrated oxide of tin will thus be
avoided. In carrying this process into operation a quantity of scraps
must be collected in a suitable drum or basket, and immersed in a tank
or vat filled with hydrochloric acid. When the tin has been dissolved,
the drum or basket is lifted out of the acid and immersed in a vat
containing water. From this bath it is finally lifted out and then
immersed for a few minutes in a third bath composed of a weak solution
of silicate of soda or potash. This last solution serves to protect the
iron clippings against rust. Experience shews that the length of time
for dissolving the tin from the iron increases with every new charge
inserted, from five to ten minutes. When it requires one hour to treat a
charge properly, nitric acid with chlorate of potash are gradually stirred
into the bath. This being done the bath acquires new strength as it
were, and a quantity of scraps can be treated in this new bath equal to
that treated in the original bath of hydrochloric acid. The saving
produced by the addition of these chemicals amounts to five hundred
pounds of hydrochloric acid, per two thousand pounds of scraps. The
solution remains perfectly clear, videlicet, no precipitation of hydrated
oxide takes place, which by the addition of nitric acid only, will occur.
When the bath is completely exhausted, that is to say, when it will
dissolve no more tin, it is drawn off into another vat or tank placed
below, and the tin is precipitated. This object is effected by means of
zine or otherwise, the tin being separated in a metallic state ready for
melting. The liquor finally obtained, consists of a solution of the
chloride of iron and zinc, which is available for the preparation of paints
or as a disinfectant, or for the preservation of wood.
In case it is desirable to obtain pure tin from the scraps, I proceed as
follows:-I first introduce the scraps into a bath of hydrochloric acid
alone, until two-thirds of the tin upon the iron has dissolved,. then I

page_text: Figures 5 and 6 shew details which will be herein-after explained.
Similar letters indicate corresponding parts throughout the Drawing.
This apparatus consists essentially of a drum or basket and a series of
tanks. The said drum or basket is made of sheet copper or copper wire,
and is suspended from a car running on an elevated track, so that the
same may be readily immersed in the liquids contained in the several
tanks.
If a drum is used it is, by preference, so arranged that it can be
revolved in each bath.
The tanks are, by preference, made of wood charred on the interior to
about one-third of the thickness thereof, and soaked in melted asphaltum
so as to present to the action of the acids and chemicals a surface of
charcoal and asphaltum. The tanks may, however, be made of wood
lined with sheets of pure rubber, which are coated with acid proof
varnish.
A is a drum, which may be made of perforated sheet copper, as shewn
in Figures 1 and 2, or of copper wire, as shewn in Figures 3, 5, and 6.
The said drum is provided with gudgeons a, a, which rest in the
arms b, b, of a yoke that serves to lift the drum from one vat into
another.
When the drum is made of perforated sheet copper, its cylindrical
body is strengthened by straps n, n, and it is secured between the
heads of traverses o, o. A door gives access to the interior of the
drum.
If the drum A is to be constructed of copper wire I cast the
gudgeons A°, A°, Figures 3 and 5, with flanges a¹, and with recesses a*
to receive the ends of traverses a³, which serve to unite the two
gudgeons. These traverses are made of T copper, and their ends are
retained in the recesses a² by means of rings passing round the same.
The said traverses are also secured to the flanges a² by means of rivets,
and internal rings a serve to strengthen and support the traverses after
the same have been secured to the gudgeons. The spaces between these
traverses are filled up by a braiding of copper wire, and for the purpose
of securing this copper wire the said traverses are perforated with a large
number of holes.

page_text: Instead, however, of using a drum, I may use a basket A°, as shewn
in Figure 4. This basket is composed of a frame which is constructed
of T or L bars of copper. In these bars are secured uprights, which are
united at their upper ends by copper bars, all of a similar shape to those
employed for the frame. The spaces between the bottom frame, the
uprights, and their connecting bars are filled up by a braiding of copper
wire.

page_text: Eleventh. A tank made of wood lined with sheets of pure india-rubber
coated with acid proof paint, as herein specified.
In witness whereof I, the said George Haseltine, have here-
unto set my hand and seal, this Tenth day of December, in
year of our Lord One thousand eight hundred and seventy-
the
three.
Witness,
H. J. NOONE,
8, Southampton Buildings,
London.
GEORGE HASELTINE. (L.S.)