IMPROVEMENTS IN THE MANUFACTURE OF ALGIN AND OTHER USEFUL PRODUCTS FROM SEAWEEDS to be as follows, that is to say :-
Year: 1884

page_text: Products from Seaweeds.
I, EDWARD CHARLES CORTIS STANFORD, of Dalmuir, in the County of
Dumbarton, North Britain, Manufacturing Chemist, do hereby declare the nature
of my said invention for "IMPROVEMENTS IN THE MANUFACTURE OF ALGIN AND
OTHER USEFUL PRODUCTS FROM SEAWEEDS to be as follows, that is to say :-
"
My said Invention comprises improvements on and developments of the processes
described in the Specification of my Patent N° 142 of 1881.
In carrying out my present Invention I take the fresh or more or less dried
seaweed, and instead of washing out the soluble salts with cold water as described
in my earlier Specification I treat it directly with carbonate of soda in dilute
solution, and steam or boil the mixture for about six hours, after which I soparato
the solution by means of a filter press, in which the cellulose is retained as a
residual cake.
The clear solution is next precipitated with dilute sulphuric or hydrochloric
acid, and the crude alginic acid thereby obtained as a precipitate is washed
and pressed into cakes, either in a suitably constructed filter press, or in an
ordinary wooden screw or other press. The cakes of insoluble algin or crudo
alginic acid thus obtained have simply to be stored in a warm room where they
become air dry.
The solution filtered off from the alginic acid is neutralised with dolly or lime-
stono dust, and the sulphate of lime precipitate allowed to settle. The clear
solution is evaporated to a density at which the sulphate of soda crystallises out
as Glauber's salts which are separated, washed, and dried in a hydroextractor. If
hydrochloric acid has been used instead of sulphuric, chloride of sodium is deposited
on evaporation and is fished out. The mother liquor is next evaporated to dryness,
and the residue is carbonised to form what is called kelp extract, and is sold for
the preparation of iodine and potash salts, as a substitute for the kelp of commerce,
compared with which, as it contains nearly double the amount of salts, and more
than double the amount of iodine, it is worth more than double the ordinary
market price. The mother liquor, contains dextrin, mucilage, and sugar, all of
which are sacrificed by the carbonization; but these may be separated by dialysis,
or by converting them into alcohol and distilling off this product, or they may be
recovered by other known means. The iodine and bromine also, may be precipitated

page_text: "
directly by adding a copper salt, or in any other known way. The iodine may be
removed by setting it free by adding nitro-sulphuric, acid, or chlorine and filtering
it through charcoal, or by distilling it off, or by other known process, if it be
desired to remove it first. Or the seaweed may at the outset be treated with
chlorine to bleach it and also set froe the iodine, which may be removed by known
means.
.
The following modifications of the process herein beforo described may also be
used. The acid liquor from which the insoluble algin or alginic acid has been
precipitated by sulphuric acid is neutralised with native magnesite or carbonate of
magnesia, and the magnesia is afterwards precipitated as carbonate by carbonate of
soda, in which way the magnesia always contained in the soluble salts of seaweed
is recovered and utilised. Or when hydrochloric acid has been used to precipitato
the algin or alginic acid, the solution may be neutralised with magnesite, in which
case on boiling the solution the chloride, bromide, and iodide of magnesium
dissociate, the magnesia being deposited and the hydrochloric, hydrobromic, and
hydriodic acids are distilled off. In either case the magnesia can be used over
again.
By another modification tho solution expressed from the cellulose and containing
the algin may be treated with chloride of calcium whoreupon alginate of calcium
will be precipitated, and from this compound soluble algin, or alginate of soda (or
sodium alginate) can be obtained by decomposing it with carbonate of soda, or the
calcium may be dissolved out with hydrochloric acid leaving the crude alginic acid.
Lime water or baryta water or a calcium or barium salt may be employed in the
same way, with similar results.
Or the solution of algin may be precipitated with aluminium chloride or
sulphate, made by dissolving bauxite in hydrochloric or sulphuric acid. Aluminium
alginate is thus obtained, from which compound alumiuin chloride or sulphate
con bo regenerated by adding hydrochloric or sulphuric acid, crudo alginic acid or
insoluble algin being left. Salts of iron, copper, or lead may also be employed in
the same way, the alginic acid being easily recovered in each case.
The crude insoluble algin or alginic acid obtained by any of the processes borein-
before described or otherwise, can be dissolved at onco in a solution of carbonato of
soda thus forming one variety of soluble algin or alginate of soda. If this is
required colorless or nearly so, the crude alginic acid is first bleached by a solution
of chloride of lime or other bleaching agent in the presence of a weak acid if
necessary. The solution is evaporated on shallow dishes or on a rotating cylinder
heated internally by steam; whereby it is obtained in transparent sheets resembling
gelatin, and forms the soluble algin or alginate of soda. The alginates of potash
and ammonia can be made in a similar way. They are soluble and like the alginate
of soda can be used for stiffening woven fabrics and for similar purposes. Calcined
magnesia or carbonate of magnesia may also be mixed with alginic acid, the two
separately insoluble substances forming a soluble alginate of magnesium which is
useful as a mordant because of the case with which both base and acid can be
rendered insoluble.
The ordinary soluble algin or alginate of soda is also by my present Invention
used for the preparation of insoluble alginates. By adding sulphate of copper to
the dissolved algin the blue alginate of copper is precipitated. This precipitate is
soluble in ammonia and becomes insoluble on drying, so that it can be used for
waterproofing canvas or paper. The following alginates have similar properties
and may be formed in the same way; namely the alginates of zinc, aluminium,
cadmium, chromium, cobalt, nickel, uranium, and platinum. Aluminium alginate
prepared by decomposing the alginate of soda by aluminium chloride or sulphate
is soluble in caustic soda, and the solution which may be made neutral is a valuablo
stiffening and dressing material for woven fabric.
The alginates of calcium, barium, and strontium are also made by decomposing
the chlorides with alginate of soda, and form usoful white compounds resembling
bone, which when dry can be turned and polished, and which may have coloring

page_text: matters combined with them. The alginate of iron made by decomposing
percbloride of iron by alginate of soda is a brown compound resembling horn when
dry and is capable of replacing it. The alginates of copper, cobalt, nickel, and
chromium are similar insoluble substances having characteristic colors.
My present Invention also comprises the combination of alginate of soda or
preferably alginate of ammonia with shellac dissolved in ammonia.
When dried
the compound formed is a tough flexible substance resembling gutta percha, and is
capable of replacing it in some of its applications. In can be rendered quite
insoluble in water. I also combine alginate of soda or alginic acid with silicate of
suda or of potash and thereby form a useful translucent compound or a kind of
flexible glass, which when dried is insoluble in water. I also use soluble alginates
for completely precipitating. iron and alumina from solution, and as dung
substitutes in Turkey-red dyeing, and generally as mordants for which they aro
well suited on account of their affinity for coloring matters. Another useful
application of soluble algin is for preventing boiler incrustation on account of its
completely precipitating lime baryta and strontia from solution in a gelatinous
form. Soluble algin can also be combined with bichromate of potash, the resulting
compound being rendered insoluble on exposure to light so that it can be used for
photographic purposes.
Finally instead of treating or applying the alginate of soda in any of the ways
herein before described it may be decomposed by prolonged boiling so as to yield
dextrine and glucose from which alcohol can be produced, or the dextrino and
glucose may bo separated by well known processes.
EDMUND HUNT,
Applicant's Agent.

page_text: Improvements in the Manufacture of Algin and other Useful
Products from Seaweeds.
I, EDWARD CHARLES CORTIS STANFORD, of Dalmuir, in the County of Dumbarton,
North Britain, Manufacturing Chemist, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN THE MANUFACTURE OF ALGIN AND OTHER USEFUL
PRODUCTS FROM SEAWEEDS," 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 comprises improvements on and developments of the processes
described in the Specification of my Patent No 142 of 1881.
In carrying out my present Invention I take the fresh or more or less dried
seaweed, and instead of washing out the soluble salts with cold water as described
in my earlier Specification I treat it directly with carbonate of soda in dilute
solution, and steam or boil the mixture for about six hours after which I separate
the solution by means of a filter or filter press in which the cellulose is retained as
a residual cake. This cellulose having certain peculiarities may be termed algulose
to distinguish it from ordinary cellulose.
The clear solution is next precipitated with dilute sulphuric or hydrochloric
acid, and the crude alginic acid thereby obtained as a precipitate is washed and
pressed into cakes, either in a suitably constructed filter press, or in an ordinary
wooden screw or other press. The cakes of insoluble algin or crude alginic acid
thus obtained have simply to be stored in a warm room where they become
air dry.
The solution filtered off from the alginic acid is neutralised with dolly or
limestone dust, and the sulphate of lime precipitate allowed to settle. Other cheap
forms of alkaline earth or alkali may be substituted for the dolly. The clear
solution is evaporated to a density at which the sulphate of soda crystallises out as
Glauber's salts, which are separated, washed, and dried in a hydroextractor. If
hydrochloric acid has been used instead of sulphuric, chloride of sodium is deposited
on evaporation and is fished out. The mother liquor is next evaporated to dryness,
and the residue is carbonised to form what is called kelp extract or kelp substitute
and is sold for the preparation of iodine and potash salts, as a substitute for the kelp
of commerce, compared with which, as it contains nearly double the amount of
salts, and more than double the amount of iodine, it is worth more than double
the ordinary market price. The mother liquor contains dextrin, mucilage, and
sugar, all of which are sacrificed by the carbonization; but these may be separated
by dialysis or by converting them into alcohol and distilling off this product, or
they may be recovered by other known means. The iodine and bromine also,
may be precipitated directly by adding a copper salt, or in any other known way.
The iodine may be removed by setting it free by adding nitro-sulphuric acid,
or chlorine and filtering it through charcoal, or by distilling it off, or by other
known process, if it be desired to remove it first. Or the seaweed may at the
outset be treated with chlorine to bleach it the iodine present being converted
into iodate.

page_text: The following modifications of the process herein before described may also be
used. The acid liquor from which the insoluble algin or alginic acid has been
precipitated by sulphuric acid is neutralised with native magnesite, or carbonate of
magnesia, and the magnesia is afterwards precipitated as carbonate by carbonate
of soda, in which way the magnesia always contained in the soluble salts of
Beaweed is recovered and utilised. Or when hydrochloric acid has been used to
precipitate the algin or alginic acid, the solution may be neutralised with magnesite,
in which case, on boiling the solution the chloride, bromide, and iodide of
magnesium dissociate, the magnesia being deposited and the hydrochloric, hydro-
bromic and hydriodic acids are distilled off. In either case the magnesia can be
used over again.
By another modification the solution expressed from the cellulose or algulose and
containing the algin may be treated with chloride of calcium whereupon alginate of
calcium will be precipitated, and from this compound soluble algin, or alginate
of soda (or sodium alginate) can be obtained by decomposing it with carbonate
of soda, or the calcium may be dissolved out with hydrochloric acid leaving the
crude alginic acid. Lime water or baryta water or a calcium or barium salt may
be employed in the same way, with similar results.
Or the solution of algin may be precipitated with aluminium chloride or sulphate,
made by dissolving bauxite in hydrochloric or sulphuric acid. Aluminium alginato
is thus obtained, from which compound aluminium chloride or sulphate can bo
regenerated by adding hydrochloric or sulphuric acid, crude alginic acid or insoluble
algin being left. Sults of metals, such as iron, copper, or lead may also be
employed in the same way, the alginic acid being easily separated and the metal
recovered in each case.
The crude insoluble algin or alginic acid obtained by any of the processes
hereinbeforo described or otherwise, can be dissolved at once in a solution of
carbonate of soda thus forming one variety of soluble algin or alginate of soda. If
this is required colorless or nearly so the crude alginic acid is first bleached by
means of chlorine or of a hypochlorite of lime soda or magnesia in the presence of a
weak acid if necessary. The solution is evaporated on shallow dishes over which
currents of air are passed or on a rotating cylinder heated internally by steam;
whereby it is obtained in transparent sheets resembling gelatin, and forms the
soluble algin or alginate of soda. The alginates of potash and ammonia can be
mado in a similar way. These are soluble and like the alginate of soda can bo
used for stiffening woven fabrics and for similar purposes. Calcined magnesia or
carbonate of magnesia may also be combined with alginic acid, the two separately.
insoluble substances forming a soluble alginate of magnesium which is useful as a
mordant because of the case with which either the base or the combined alginic
acid can be rendered insoluble.
The ordinary soluble algin or alginate of soda is also by my present Invention
used for the preparation of insoluble alginates by double decomposition. By adding
sulphate of copper to the dissolved algin the blue alginate of copper is precipitated.
This precipitate is soluble in ammonia and becomes insoluble on drying, so that
it can be used for waterproofing canvas or paper. The following alginates have
similar properties and may be formed in the same way; namely the alginates of
zinc, aluminium, cadmium, chromium, cobalt, nickel, uranium, and platinum.
Aluminium alginate prepared by decomposing the alginate of soda by aluminium
chloride or sulphate is soluble in caustic soda, and the solution which may be made
quite neutral is a valuable stiffening and dressing material for woven fabrics.
The alginates of calcium, barium, and strontium are also made by decomposing
the chlorides with alginate of soda, and form useful white compounds resembling
bone, which when dry can be turned and polished, and which may have coloring
matters combined with them. The alginate of iron made by decomposing
perchloride of iron by alginate of soda is a brown compound resembling horn when
dry and is capable of replacing it. The alginates of copper, cobalt, nickel, and
chromium are similar insolublo substances having characteristic colors. My present

page_text: Invention also comprises the combination of alginate of soda or preferably alginato
of ammonia with shellac dissolved in ammonia by mixing the two together. When
dried the compound formed is a tough flexiblo substance resembling gutta percha
and is capable of replacing it in some of its applications. It can be rendered
quite insoluble in water. In a similar way any resin, such as copal, which is
soluble in ammonia may be combined by mixing with the alginate of ammonia.
I also combine alginate of soda or alginic acid with silicate of soda or of potash
and thereby form á useful translucent compound or a kind of flexible glass, which
when dried is insoluble in water. I also use soluble alginates for completely
precipitating iron and alumina from solution, and as dung substitutes in Turkey-
red dyeing, and generally as mordants for which they are well suited on account of
their affinity for coloring matters. Another useful application of soluble algin is
for preventing boiler incrustation on account of its completely precipitating lime
baryta and strontia as well as alumina and iron from solution in a gelatinous form.
Soluble algin can also be combined or mixed with bichromate of potash, the
resulting compound being rendered insoluble on exposure to light so that it can be
used for photographic purposes.
Finally instead of treating or applying the alginate of soda in any of the ways
hereinbefore described it may be decomposed by prolonged boiling so as to yield
dextrine and glucose from which alcohol and acetic acid can be produced, or the
dextrine and glucose may be separated by well known processes.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed I declare that what
I claim is
1. The improved process for obtaining algin from seaweeds, and consisting
principally in treating fresh or more or less dried seaweed directly with carbonate
of soda substantially as herein before described.
2. The modified process in which the seaweed is bleached or treated with
chlorine before being treated with carbonate of soda substantially as hereinbefore
described.
3. The combination of processes for obtaining useful products from seaweeds in
which the algin is first separated by treatment with carbonate of soda and
precipitation by a suitable acid or salt, and the other constituents are subsequently
separated by suitable known processes substantially as hereinbefore described.
4.-The obtaining of useful products or compounds having algin obtained from
seaweeds as a constituent by means of a double decomposition of alginate of soda
with metallic or other salts substantially as hereinbefore described.
"
5.-The obtaining of useful products or compounds having algin obtained from
seaweeds as a constituent by mixing a soluble alginate with an ammoniacal
solution of shellac or other resin or with a soluble silicate substantially as herein- 4
before described.