AN IMPROVED PROCESS FOR EXTRACTING IODINE, BROMINE, AND OTHER SALTS FROM SEA WRACK OR SEA WEED
Year: 1879

page_text: LETTERS PATENT to Henry Bernoulli Barlow, of Manchester, in the County
of Lancaster, Patent Agent, for the invention of "AN IMPROVED PROCESS
FOR EXTRACTING IODINE, BROMINE, AND OTHER SALTS FROM SEA WRACK OR
SEA WEED." A communication from abroad by Jerome Narcisse Jouveau-
Dubreuil, of Paris, France.
PROVISIONAL SPECIFICATION left by the said Henry Bernoulli Barlow at
the Office of the Commissioners of Patents on the 4th January 1879.
HENRY BERNOULLI BARLOW, of Manchester, in the County of Lancaster, Patent
Agent.
AN IMPROVED PROCESS FOR EXTRACTING IODINE, BROMINE, AND OTHER
SALTS FROM SEA WRACK OR SEA WEED." A communication from abroad by Jerome
Narcisse Jouveau Dubreuil, of Paris, France.
"
The seaweeds (and particularly those descriptions known in France as "goëmon
and varech") as collected fresh from the sea, are submitted to the action of any
suitable disintegrating or triturating machine until they are reduced to a fine
pulp.
In order to separate the juices from the fibrous parts of the sea weed I add
to the mass about 4 per cent. of milk of lime. The vessels containing the sea weed
and the milk of lime are provided with agitators to mix the whole together.
The whole mass is left to stand for about 12 hours, and is then subjected to the
action of a hydraulic press or other equivalent to extract the juice from which the
iodine or other salt is precipitated by the usual chemical agents.
The residue left is washed with water, and this water may be used for slacking
the line for the next process.
The quantity of iodine or other salt obtained depends on the quality of the sea-
weed, the best being that obtained in deep water, but that thrown by the waves on
the shore may be employed.
The products left after extracting the iodine, bromine, and other salts make a
valuable manure.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Bernoulli Barlow in the Great Seal Patent Office on the 30th
June 1879.
HENRY BERNOULLI BARLOW, of Manchester, in the County of Lancaster, Patent
Agent. AN IMPROVED PROCESS FOR EXTRACTING IODINE, BROMINE, AND OTHER
SALTS FROM SEA WRACK OR SEA WEED." A communication from abroad by Jerome
Narcisse Jouveau-Dubreuil, of Paris, France.
The nature of this Invention consists in an improved mode of treating the sea-
wrack or sea-weed known in France under the names of " goëmons and varechs,"
whether obtained from deep water or thrown by the waves on the shore, in order to
extract the natural juices of these plants and to obtain by a direct process from
these juices the useful salts which they contain, and particularly iodine and
bromine.
"
The fresh" goëmons and varechs after having been left to drain are submitted
to any suitable disintegrating or triturating machine until they are reduced to a
fine moist pulp, but which does not allow the juices to escape owing to the viscous
nature of the plants. I then add to the pulp about four per cent, of lime or milk of
lime, but this proportion may be exceeded without injury.
I recommend lime because it is cheap and abundant, but any other substance
possessing similar properties or producing the same result may be used.
The vessels containing the seawrack or seaweed and the lime or other equivalent
are provided with agitators by which the whole are mixed together.
The mixture is left to stand for about twelve hours. after which the mass becomes
compressible, it is then taken to a press or to a centrifugal machine in order to
extract all the juices.
The solid residue is a valuable manure, which is prepared in cakes or in powder.
The peculiar feature of novelty in this Invention is to dispense with the tritura-
ting in water and the frequent washings, which augment the volume of liquid to be
evaporated and increase the plant and the fuel out of proportion to the weight of
the useful articles produced. In order to reduce the quantity of water used I employ
the liquid that is drained off the seaweed to slake the lime required to produce the
ilk of lime: 1 also use for the same purpose the water for washing the residue
after the juices have been poured off.
The quantity of iodine or other salt obtained depends on the quality of the sea-
weeds, the richest are those obtained from deep sea, but as these can only be obtained
by boats during high tides it is necessary to store the requisite quantity for a con-
tinuous supply in covered sheds having a cemented or other suitable floor which is
sufficiently inclined to allow the juices that drain off to be collected. These juices
contain a considerable amount of iodine or other salis, and they are stored in reser-
voirs to be used in obtaining the milk of lime.
After the triturated seaweed has been pressed the juices are left to stand, then
they are drawn off and treated in the following manner: A certain quantity of
nitric acid or sulphuric acid charged with nitrous vapour is poured into the juices
to liberate the iodine, the mixture is then agitated, and about one per cent. of ground
charcoal of seaweed is combined with the whole.
The quantity of ground charcoal employed must be in proportion to the amount
of iodine or other salts in the juices and to the absorbing power of the charcoal.
The charcoal is produced by the combustion of the seaweed in a closed vessel
after the seaweed has been deprived by frequent washings of all the iodine which it

page_text: contained and of its mineral salts by washing with hydrochloric acid. The separa-
tion takes place rapidly, and the juices free from iodine are separated by decantation
or filtration. The charcoal charged with iodine is freed from acid by frequent
washings.
In order to obtain the raw iodine it is only necessary to calcine the dried charcoal
mixed with bi-oxide of manganese and treated with sulphuric acid.
I obtain iodine of potassium directly by washing the iodised charcoal with caustic
potash, or indirectly by treating the iodised charcoal with a metal such as iron or
lime, capable of supplying a soluble iodide, or an indecomposable iodide by heat,
and soluble, like manganese, or insoluble, like copper. These iodides are after-
wards decomposed by a carbonate or a caustic alkali to obtain the corresponding
iodides.
The regenerated charcoal serves for another process.
Although for manufacturing purposes I prefer seaweed charcoal I reserve to
myself the use of any other charcoal, whether vegetable, animal, or mineral, pro-
viding it possesses the property of absorbing iodine, or I can make use of wood, tan,
bark, or other equivalents finely pulverised, or argillaceous or siliceous or other
substances which act by absorption.
Seawrack or seaweed in a dry state and broken into small pieces can be operated
upon by ordinary azotic acid until it is completely impregnated. When submitted
to a moderate heat the azotic acid is decomposed by contact with the seaweed and
is separated from the nitrous vapours, which are conveyed into azotic acid, where
they dissolve.
The acid thus prepared is particularly suitable for the process of separating the
iodine by charcoal, as above described, and it can also be employed for all purposes
where the acide azotique rouge fumant is used. These nitrous vapours may also
be used to displace iodine from iodides in acidified liquors.
This Invention consists in the mode of producing nitrous vapours, as described,
whether for making acide azotique rouge fumant and separating them from
iodine as well as for the nitrification of any other compound.
This process of separating the iodine from the juices without the previous opera-
tions of evaporating or caleining and the process of producing nitrous vapours form
the principal part of this Invention, the object of which is to extract the valuable
juices from the fresh seaweed by mechanical processes. I wish it to be understood
that I reserve the right to make the instruments or apparatus of any description of
charcoal or other porous substance which would separate by absorption the iodine,
bromine, or other salts from the juices or other liquids containing them.
Having thus stated the nature and particulars of the Invention communicated to
me by the within named Jerome Narcisse Jouveau-Dubreuil, 1 declare that I
claim
66
First. The mode of treating the fresh seawrack or seaweed known in France as
goëmons and varechs," by disintegrating or triturating by the addition of lime or
milk of lime to the moist pulp, and then extracting the juices of the plants by
pressure or otherwise, as described.
Secondly. The mode of extracting the iodine or other salts from the natural
juices of the fresh seaweeds by the combined action of azotic or sulphuric acid
charged with nitrous vapours and pounded charcoal or other absorbent as described.
Thirdly. The preparation of charcoal made of varech or other seaweed to absorb
the iodine or other salts liberated from the natural juices of the bresh seaweeds.
Fourthly. The preparation of nitrous vapours by the action of nitric acid on dry
goëmons" broken into small pieces, as described.
"
Fifthly. Obtaining direct alkaline or other iodides by treating iodised charcoal in
the manner and for the purpose described; and

page_text: Lastly. The use of fresh" goëmons and varechs" after being pressed and mixed
with lime as manure in the form of cakes or powder, as described.
In witness whereof, I the said Henry Bernoulli Barlow, have hereunto set my
hand and seal, this Twenty eighth day of June, One thousand eight
hundred and seventy nine.
H. P. BARLOW. (L..S.)