IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL ALIZARIN
Year: 1880

page_text: LETTERS PATENT to Albert Domeier, of Botolph Lane, in the City of London,
and Joseph Marzell, of Woburn Place, Russell Square, in the County of
Middlesox, for an Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
ARTIFICIAL ALIZARIN."
PROVISIONAL SPECIFICATION left by the said Albert Domeier and Joseph
Marzell at the Office of the Commissioners of Patents on the 7th July 1880.
ALBERT DOMEIER, of Botolph Lane, in the City of London, and JOSEPH
MARZELL, of Woburn Placo, Russell Square, in the County of Middlesex.
"IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL ALIZARIN."
(1). The melt or product containing the alizarin combined with alkali is treated
with sulphurous acid in order to precipitate the alizarin and to form bisulphite
salt with the alkali.
'
(2). The liquors containing the bisulphite salt of the alkali in solution are
separated from the alizarin paste, and can be worked in either of the following
ways:-
(A). They are mixed with acids (sulphuric or muriatic for example) in order to
evolve sulphurous acid, which can be used for other operations or otherwise; or
(B). They are treated with lime or other suitable materials for the purpose of
recovering the alkali in the caustic form or otherwise. The sulphito of lime or
other sulphito salt resulting from this process can be decomposed with acids in
order to recover the sulphurous acid.
17
By the terms "artificial alizarin or "alizarin," as hereinbefore employed, we
mean the products commercially known as "artificial alizarin," and which are
made from coal tar products, whether they be pure alizarin, or any pure purpurin
or mixture of purpurins, or mixture of alizarin with one or more purpurins.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Albert Domeier and Joseph Marzell in the Great Seal Patent Office
on the 7th January 1881.
ALBERT DOMEIER, of Botolph Lane, in the City of London, and JOSEPH
MARZELL, of Woburn Place, Russell Square, in the County of Middlesex.
IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL ALIZARIN."
"
The so called melt or product obtained in the conversion of the anthraquinone
sulpho salts into artificial alizarin contains the alizarin combined with alkali and
mixed with the excess of alkali not used in the reaction, and sulphite of alkali
derived from the reaction of the conversion stated above.
The melt is diluted with water and then treated with sulphurous acid until
perfectly neutralized; the melt originally containing about 4000 lbs. of caustic
alkali is generally diluted with about 3500 to 3700 gallons of water.
The sulphurous acid is conveniently introduced in the form of gas, and driven
into the solution by means of an air pump or injector.
.
The result of the reaction will be, firstly, bisulphite of alkali which remains
in solution; secondly, precipitation of the free alizarin.
The-precipitated-alizarin-is-separated-from-the-liquor by means of filter presses
or other suitable means, and then thoroughly washed.
The liquors containing the alkaline bisulphite are run into tanks, allowed to
cool, and then diluted.
Wo prefer a proportion of about 1 part of alkali to about 27 parts of water.
The liquors are then treated with caustic lime until neutralization is perfect. The
result of this decomposition will be the formation of,-
Firstly. Caustic alkali, which remains in solution.
Secondly. Sulphite of lime which precipitates.
The caustic alkaline liquors are drained off and evaporated in a suitable
apparatus; they are first concentrated to about 36° Beaune, when on cooling they
further deposit sulphite and the greater part of their impurities.
After separation of these the alkaline liquors are further concentrated as
required.
The sulphite of lime can be decomposed with spent acids, sulphuric or muriatic
for instance, as derived from other manufacturing processes or resulting from other
operations followed in making artificial alizarin, for the purpose of recovering the
sulphurous acid for further use.
The liquors of alkaline sulphite may also be treated as above with spent acids, in
order to recover the sulphurous acid.
Instead of employing caustic lime, as hercinbefore described, we sometimes employ
caustic baryta or strontia.
By the term artificial alizarin, as herein employed, we mean either alizarin or
purpurin, or mixtures thereof, and which are commercially known as alizarin.
What we claim is,―
Firstly. The treatment of the alizarin melt with sulphurous acid, the separation
of the precipitated alizarin, and the treatment of the alkaline sulphite liquors with
caustic lime, baryta, or strontia, in order to obtain or recover caustic alkali and
sulphite of lime, baryta, or strontia, substantially as herein before described.
Secondly. The treatment of the alizarin melt with sulphurous acid, the
separation of the precipitated alizarin, and the decomposition of the alkaline

page_text: sulphite liquors with acids in order to recover sulphurous acid for further operations,
substantially as herein before described.
In witness whereof, I, the said Albert Domeier, on behalf of myself and the
said Joseph Marzell, have hereunto set my hand and seal, this Seventh
day of January, One thousand eight hundred and eighty one.
A. DOMEIER. (L.S.)