IMPROVEMENTS IN THE MANUFACTURE OF IODINE
Year: 1862

page_text: LETTERS PATENT to William Paterson, of Glasgow, in the County of
Lanark, North Britain, Manufacturing Chemist, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF IODINE."
66
IMPROVEMENTS IN THE MANUFACTURE OF IODINE."
PROVISIONAL SPECIFICATION left by the said William Paterson at the
Office of the Commissioners of Patents, with his Petition, on the 29th
March 1862.
I, WILLIAM PATERSON, of Glasgow, in the County of Lanark, North Britain,
Manufacturing Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF IODINE," to be as follows, that is
to say
This Invention relates to improvements in the process of manufacturing
iodine in a more economical manner than has hitherto been practised.. Under
one modification of these improvements the "residual still liquor" which
remains in the still, after the separation of the iodine has been effected in the
ordinary. way, is used to neutralise or decompose, to a considerable extent, the
sulphur compounds and carbonates existing in kelp leys. The residual still
liquor is applied to a fresh charge of kelp leys, and in this manner a saving of
sulphuric acid is effected and the salts of potash and soda which are contained
in the residual still liquor are recovered. The precipitate which is obtained
consists of compounds of sulphur, manganese, and iron, and occasionally car-
bonates of these metals. The clear supernatant liquor may be disposed of in

page_text: any convenient manner. The precipitate, after being washed in water, may
be employed for the purpose of saturating the free acid contained in the
residual still liquor. Or in lieu of this mode of operation the "residual still
liquor may be evaporated to dryness and applied to the kelp for the
purpose
the alphur compounds and carbonatos
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Paterson in the Great Seal Patent Office on the
27th September 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
PATERSON, of Glasgow, in the County of Lanark, North Britain, Manufac-
turing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of March, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Paterson, Her special license that I, the said William
Paterson, my executors, administrators, and assigns, or such others as I, the
said William Paterson, my executors, administrators, or 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 MANUFACTURE OF IODINE," upon the condition (amongst others) that I, the
said William Paterson, my executors or administrators, by an instrument in
writing under my hand and seal, or under the hand and seal of one of them,
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 calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Paterson, 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 :-
My said Invention relates to improvements in the process of manufacturing
iodine in a more economical manner than has hitherto been practised. Under
one modification of these improvements, the "residual still liquor" which

page_text: remains in the still after the separation of the iodine has been effected in the
ordinary way, is used to neutralise, or decompose, to a considerable extent,
the sulphur compounds and carbonates existing in kelp leys. The residual
still liquor is applied to a fresh charge of kelp leys, and in this manner a saving
of sulphuric acid is effected and the salts of potash and soda which are con-
tained in the residual still liquor are removed. The precipitate which is
obtained consists of compounds of sulphur, manganese, and iron, and occa-
sionally carbonates of these metals. The clear supernatant liquor may be
disposed of in any convenient manner. The precipitate, after being washed
in water, may be employed for the purpose of saturating the free acid con-
tained in the residual still liquor." Or in lieu of this mode of operation the
"residual still liquor" may be evaporated to dryness and applied to the
kelp: for the purpose of partially decomposing the sulphur compounds and
carbonates.
And in order that my said Invention of "Improvements in the Manufacture
of Iodine" may be properly understood I shall now proceed to describe in
detail certain modifications under which my improvements may be judiciously
carried out in practice; that is to say, according to one mode of procedure in
the manufacture of iodine it is usual to supersaturate the leys obtained from
kelp by means of sulphuric acid. To the leys or alkaline solution the sulphuric
acid is added in sufficient quantity to decompose the 'sulphur compounds and
carbonates contained in the leys. Simultaneously with this decomposition the
iodine contained in the compound solution is released by means of the addition
thereto of a sufficient quantity of the binoxide of manganese. The addition
of the binoxide of manganese favours the production of iodine which is thus
produced in larger quantity. After the separation of the iodine there remains
in the distillatory apparatus a quantity of acidulous liquid ordinarily known as
the "residual still liquor," which contains a considerable proportion of the
sulphates of manganese and iron as well as of free sulphuric acid.. The object
of the present Invention is to employ this "residual still liquor" in the manu-
facture of iodine, which has not hitherto been done, and thereby effect a
further economy in the manufacturing process. The residual still liquor is
employed to neutralise or decompose, to a considerable extent, the sulphur
compounds and carbonates contained in the kelp leys in lieu of first adding
sulphuric acid thereto, according to the ordinary mode herein-before described.
In this way a considerable saving of sulphuric acid is effected, and at the
same time a further economy is obtained by the recovery of the salts of potash
and soda contained in the "residual still liquor," which combine with the
similar salts in the alkaline solution. The "residual still liquor" is added to

page_text: the kelp leys in sufficient quantity to effect the required decompositions in a
satisfactory manner. The proportion of the residual still liquor may require
to be varied to some extent, according to the nature of the alkaline solution
under operation. After the combination of the kelp leys with the residual
still liquor is effected a precipitate is obtained which consists of certain com-
pounds of sulphur, manganese, iron, and occasionally of carbonates of man-
ganese and iron. The clear supernatant liquor is drawn off from above the
precipitate and allowed to run to waste, or is otherwise disposed of and applied
to any useful purpose for which it may be suitable. The precipitaté is then
washed with water and may be usefully employed to saturate the free acid
contained in another batch or quantity of residual still liquor. Another mode
of treating the residual still' liquor is to evaporate it to dryness when the kelp
under operation-renders this variation of the process desirable; the dried
residuum is employed in the same manner as herein-before described. With
these improvements the manufacture of iodine may be carried out with greater
economy and a smaller expenditure of material than heretofore.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion, that what I consider novel and
'original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is, the system or mode of manufacturing
iodine in which the "residual still liquor" is utilized and applied to the kelp
leys for the purpose of neutralising and decomposing, or partly so, the salts
contained therein, and thereby economise the quantity of sulphuric acid which
would otherwise be required; also the application of the precipitate of the
compound solution for the purpose of saturating the free acid contained in the
"residual still liquor" of the iodine manufacture, as herein-before described.
In witness whereof, I, the said William Paterson, have hereunto set my
hand and seal, this Twenty-sixth day of September, One thousand
eight hundred and sixty-two.
WILLIAM PATERSON.
!
(L.B.)