IMPROVE- MENTS IN THE SEPARATION AND UTILISATION OF CERTAIN MIXED CHEMICAL PRODUCTS
Year: 1874

page_text: LETTERS PATENT to Charles Lowe, of Reddish, in the County of
Lancaster, Manufacturing Chemist, for the Invention of "IMPROVE-
MENTS IN THE SEPARATION AND UTILISATION OF CERTAIN MIXED CHEMICAL
PRODUCTS."
Sealed the 2nd April 1874, and dated the 3rd February 1874.
PROVISIONAL SPECIFICATION left by the said Charles Lowe at the
Office of the Commissioners of Patents, with his Petition, on the
3rd February 1874.
I, CHARLES LOWE, of Reddish, in the County of Lancaster, Manu-
facturing Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE SEPARATION AND UTILISATION OF CERTAIN MIXED
CHEMICAL PRODUCTS," to be as follows:―
The object of this Invention is to separate the sulphuric and picric
acids existing in the dilute acid liquors obtained in the manufacture of
picric acid, thereby rendering both these products capable of separate
utilisation, and giving them increased commercial value.

page_text: To carry out the object of this Invention I take the dilute acid liquors
containing sulphuric acid and picric acid obtained in the manufacture
of picric acid as a bye product and concentrate the said dilute acid
liquors by rectification in any suitable vessel or vessels. On rectification
I find that as the temperature of the mixture gradually approaches the 5
boiling point of mono-hydrated sulphuric acid the picric acid gradually
distils in part with the water of the dilute acid but only entirely just
previously to the acid residue attaining the boiling point of mono-
hydrated sulphuric acid. The acid residue of rectification constitutes
and may be re-employed as ordinary rectified sulphuric acid in the 1
process of manufacture of picric acid, or for other purposes.
The mixed fluid and solid distillates obtained in the above-mentioned
process of rectification I re-employ in the crystallizing and diluting
processes made use of in the course of the manufacture of picric acid.
SPECIFICATION in pursuance of the conditions of the Letters Patent, 1
filed by the said Charles Lowe in the Great Seal Patent Office on
the 31st July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
Lowe, of Reddish, in the County of Lancaster, Manufacturing Chemist,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of February, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charles Lowe, Her special licence
that I, the said Charles Lowe, my executors, administrators, and assigns,
or such others as I, the said Charles Lowe, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN THE SEPARATION AND
UTILIZATION OF CERTAIN MIXED CHEMICAL PRODUCTS," upon the condition
(amongst others) that I, the said Charles Lowe, my executors or admini-

page_text: strators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature of
the said Invention, and in. what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office, within
six calender months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Charles Lowe, do hereby declare the
nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement (that is to say) :-
The object of this Invention is to separate the sulphuric and picric
acids existing in the dilute acid liquors obtained in the manufacture of
picric acid, thereby rendering both these products capable of separate
utilization and giving them increased commercial value.
To carry out the object of this Invention I take the dilute acid liquors
containing sulphuric acid and picric acid obtained in the manufacture
of picric acid as a bye product and concentrate the said dilute acid
liquors by rectification in any suitable vessel or vessels. On rectification
I find that as the temperature of the mixture gradually approaches the
boiling point of mono-hydrated sulphuric acid the picric acid gradually
distils in part with the water of the dilute acid, but only entirely just
previously to the acid residue attaining the boiling point of mono-
hydrated sulphuric acid. The acid residue of rectification constitutes
and may be re-employed as ordinary rectified sulphuric acid in the
process of manufacture of picric acid, or for other purposes.
The mixed fluid and solid distillates obtained in the above-mentioned
process of rectification I re-employ in the crystallizing and diluting
processes made use of in the course of the manufacture of picric acid.
Having thus stated the nature and particulars of my Invention I wish
it to be understood that I do not intend to limit myself to the precise
details given, as they may be varied or modified; and I claim, the
separation of sulphuric and picric acids existing together in dilute
solution by the application of a process of rectification in suitable vessels,
during which process of rectification the boiling point of the acid mixture
is sufficiently raised to insure the separation of the picric acid contained

page_text: in it by distillation, and the re-application of the products so separately
obtained.
In witness whereof, I, the said Charles Lowe, have hereto set my
hand and seal, this Thirtieth day of July, One thousand eight
hundred and seventy-four.