IMPROVE- A DOVIDING ANIMAL CHARCOAL
Year: 1874

page_text: LETTERS PATENT to William Whitthread, of Liverpool, in the County:
of Lancaster, Analytical Chemist, for the Invention of "IMPROVE-
A
DOVIDING ANIMAL CHARCOAL "
MENTS IN CLEANSING AND REVIVIDYING ANIMAL CHARCOAL

page_text: may be therein, is then treated with an alkali, alkaline carbonate, or
mixture thereof in solution, to carry off coloring matter and other
impurities, soda, hydrate, or carbonate being preferred. The greater
part of the alkaline matter is now removed by washing, after which any
remaining portion of such alkaline matter is washed out by water
surcharged with carbonic or sulphurous acid; carbonic acid being
preferred. The essential novelty of the above first head consists in the
washing out of the alkaline matter by water surcharged with carbonic or
sulphurous acid.
Under the second part or revivifying process used or spent charcoal,
preferably cleansed as described under the above first part, although
such cleansing may be dispensed with, is treated with dicalcic phosphate
dissolved in water, surcharged with carbonic or sulphurous acid, or with
dicalcic phosphate dissolved in a solution of monocalcic phosphate in
combination with carbonic or sulphurous acids.
Instead of adding the dicalcic phosphate in solution I may mix it
with the charcoal and afterwards add water and carbonic or sulphurous
acid, thus forming the solution in the mass of charcoal.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Whitthread in the Great Seal Patent
Office on the 30th March 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
WHITTHREAD, of Liverpool, in the County of Lancaster, Analytical a
Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of September, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors, give a
and grant unto me, the said William Whitthread, Her special licence
that I, the said William Whitthread, my executors, administrators, and
assigns, or such others as I, the said William Whitthread, my executors,
administrators, and assigns, should at any time agree with, and no

page_text: Instead of adding the dicalcic phosphate in solution I may mix it
with the charcoal and afterwards add water and carbonic or sulphurous
acid, thus forming the solution in the mass of the charcoal.
After being treated as above the charcoal may be washed with
water.
I have found that from one-half to two parts by weight of solid
sodium hydrate added to one hundred parts of charcoal estimated as
dry (the charcoal being covered with hot water) answers well, when a
small quantity, say one per cent. of dicalcic phosphate, is afterwards
added, with sufficient carbonic or sulphurous acid to hold the phosphate
in solution.
Having now described the nature of my said Invention, and so
particularized it that others will be enabled to put it in practise, I
claim,―
First. Treating used or spent charcoal, substantially as described
under the first part.
Second. Revivifying used or spent charcoal, substantially as described
under the second part.
In witness whereof, I, the said William Whitthread, have herc-
unto set my hand and seal, the Thirtieth day of March, in the
year of our Lord One thousand eight hundred and seventy-
five.
WILLIAM WHITTHREAD. (L.S.)