Manufacture of Monosulphonated Anthracene Acid by the Direct Sulphonation of Anthracene.
Year: 1893

page_text: Date of Application, 20th Jan., 1893
Complete Specification Left, 13th Oct., 1893-Accepted, 18th Nov., 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by LA SOCIÉTÉ ANONYME DES MATIÈRES COLO-
RANTES ET PRODUITS CHIMIQUES DE ST. DENIS, and DOCTOR CHAPIUS
all of 105, Rue Lafayette, Paris, France.]
Manufacture of Monosulphonated Anthracene Acid by the Direct
Sulphonation of Anthracene.
I, JOHN IMRAY of No. 28 Southampton Buildings in the County of London,
Consulting Engineer and Chartered Patent Agent, do hereby declare the nature
of this invention to be as follows:-
The only process heretofore known for the manufacture of monosulphoanthracene
is that indicated by Liebermann (Berichte 12) by reducing the monosulphoanthra-
quinone salt of sodium.
The endeavours inade to obtain this monosulphonated anthracene directly by the
sulphonation of the carburet have all failed from an industrial point of view.
In an old treatise upon the derivatives of anthracene, Graebe and Liebermann
(Berichte 1 p. 187) state having obtained small quantities of a sulphonated
derivative of anthracene in yellow crystals in the form of a lead salt, corresponding
to the formula: (C"H'SO³) 2 Pb. Later on, Liebermann (Liebigs Annales 212
p. 43) having found that the acid thus obtained, when oxidised and transformed
into alizarine by the ordinary processes, only gave small quantities of this
colouring matter, abandoned the process and recommended the reduction of
monosulphoanthraquinone.
Lastly, Lincke (Journal fur praktische Chemie N.F. 11, 222) announced the
formation of two isomeric monosulphonated acids obtained by the action of concen-
trated sulphuric acid upon anthracene at a temperature of 100° C. The assertions
of Lincke, when tested by Liebermann (Ber. 12-589) were found by him to be
incorrect, as he states that, in following very exactly the conditions indicated by
the author, he had only been able to obtain disulphonated acids, without being able
to separate the monosulphonated acids indicated. These statements have not been
contradicted.
My correspondents have found the results stated by Liebermann to be confirmed
every time they have acted upon anthracene with concentrated sulphuric acid
at 66° Be.; but on the other hand, when they have employed for the sulphonation
an acid of lower concentration than 66° Be., they have obtained the monosulpho-
anthracene in variable proportions, the results being all the better, the nearer the
concentration of the acid approached 53° to 54° Be.
Under these conditions the yields have been as high as from 55 to 60 per cent. of
the anthracene employed, while at the same time a small quantity of anthracene
remained unattacked, and disulphonated acids were produced, among which were
characterised the a, ẞ, and
Υ
acids.

page_text: means of carbonate of soda, and allowed to crystallise. The soda salt of the mono-
sulphonated acid, practically insoluble in cold water, crystallises in a yellowish
mass. This is placed on a filter for separating the soluble constituents, and a
simple recrystallisation in hot water of the part remaining on the filter is sufficient
to give the monosulphoanthracene-soda salt in a very pure state, only mixed with a
small quantity of anthracene not acted upon.
thus obtained
The characteristics of the salts of the mono-sulpho-anthracene-acid
by direct sulphonation are identical with those of the acid described by Liebermann
and derived from mono-sulpho-anthraquinone salt of soda.
My correspondents have also found that by oxidation, either by means of
chromic acid, or by nitric acid or nitrates, the said mono-sulpho-anthracene-acid is
transformed into mono-sulphonated anthraquinone, and eventually into alizarine,
with almost quantitative yields.
The alizarine thus obtained possesses a high degree of purity.
This mono-sulpho-anthracene-acid serves as primary matter, either for obtaining
alizarine or for the production of sulphonated acids of a higher degree of sulpho-
nation, which also serve for the preparation of corrresponding anthracenic coloring
matters.
Dated this 20th day of Januar 1802
ABEL & IMRAY,
Agents for the Applicant.
.
.
COMPLETE SPECIFICATION.
Manufacture of Monosulphonated Anthracene Acid by the Direct
Sulphonation of Anthracene.
I, JOHN IMRAY, of No. 28, Southampton Buildings, in the County of London,
Consulting Engineer and Chartered Patent Agent, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
The only process heretofore known for the manufacture of mono-sulpho-
anthracene is that indicated by Liebermann (Berichte 12) by reducing the mono-
sulpho anthraquinone salt of sodium.
The endeavours made to obtain this monosulphonated anthraceue directly by the
sulphonation of the carburet have all failed from an industrial point of view.
In an old treatise upon the derivatives of anthracene, Graebe and Liebermann
(Berichte 1 p. 187) state having obtained small quantities of a sulphonated
derivative of anthracene in yellow crystals in the form of a lead salt, corresponding
to the formula: (CH'SO³) Pb. Later on, Liebermann (Liebigs Annales 212
p. 43) having found that the acid thus obtained, when oxidised and transformed
into alizarine by the ordinary processes, only gave small quantities of this
colouring matter, abandoned the process and recommended the reduction of mono-
sulpho-anthraquinone.
Lastly, Lincke (Journal fur praktische Chemie N.F. 11, 222) announced the
formation of two isomeric monosulphonated acids obtained by the action of
sulphuric acid upon anthracene at a temperature of 100° C. The assertions of
Lincke, when tested by Liebermann (Ber. 12-589) were found by him to be
incorrect, as he states that, in following very exactly the conditions indicated by
Lincke, he had only been able to obtain disulphonated acids, without being able
to separate the mono sulphonated acids indicated. These statements have not been
contradicted.
My correspondents have found the results stated by Liebermann to be confirmed
every time they have acted upon anthracene with concentrated sulphuric acid
at 66° Be.; producing only disulpho anthracene; but, on the other hand, when
they have employed for the sulphonation an acid of lower concentration than
66° Be. they have obtained the mono sulpho anthracene in various proportions,

page_text: of the anthracene employed, while at the same time a small quantity of anthracene
remained unattacked, and disulphonated acids were produced, among which were
characterised the a, ẞ and y acids, as well as a new acid giving by oxidation and
fusion anthra purpurine the preparation and properties of which are hereinafter
set forth.
t
PREPARATION OF MONOSULPHATED ANTHRACENE ACID.
There are introduced into a vessel with agitator:
100 kilos. of pure anthracene of high per centage such as 75 to 85 per cent.
200 kilos. of sulphuric acid of 53° Bé.
The mixture is heated during several hours between 120° to 135° C. until a
sample indicates the almost complete disappearance of the anthracene.
:
The mixture is then diluted in 1,000 litres of boiling water, neutralised by
means of carbonate of soda, and left to crystallise. The soda salt of the mono-
sulphonated acid, practically insoluble in cold water, crystallises in a mass of
greenish shot colour. This is placed on a filter for separating the soluble
constituents, and a simple recrystallisation in hot water of the part remaining on
the filter is sufficient to give the mono sulpho anthracene-soda salt in a very pure
state, only mixed with a small quantity of anthracene not acted upon.
The characteristics of the salts of the mono-sulpho-anthracene-acid thus obtained
by direct sulphonation are identical with those of the acid described by Liebermann
and derived by reduction of mono-sulpho-anthraquinone salt of soda.
My correspondents have also found that by oxidation, either by means of
chromic acid, or by nitric acid the said mono-sulpho-anthracene-acid is trans-
formed into mono-sulphonated anthraquinone, and eventually produces alizarine,
with almost quantitative yields.
After separating the monosulphonated anthracene acid a mixture is readily
obtained of two disulphonated anthracene acids giving by oxidation the two known
disulphonated anthraquinone acids a and B. From this mixture by taking
advantage of the difference in solubility of the baryta salts, there can be obtained
in a pure state a disulphonated anthracene acid not hitherto described which, by
oxidation gives the 3 disulpho anthraquinone and ultimately by fusion anthra-
purpurine. The first separation can be effected in either of two ways.
1. The mother liquor which results from the sulpho conjugation of the anthracene
and from which the monosulphonated derivative has been precipitated by salt, has
added to it 15 per cent. of hydrochloric acid and the mixture is heated for 5 hours
in a closed vessel at a temperature of 210° to 215° C. under a pressure of 12 to
15 kilos. In these conditions, of the disulphonated acids formed in small quantity
during the sulphonation, the one set are restored to the state of mono sulpho-
anthracene or anthracene, while the other set retain the whole of their sulphuric
acid. At the end of the operation there remain only the two disulphonated acids
above mentioned. After treatment of the mother liquor in the closed vessel there
are found as a precipitate anthracene crystallised in spangles, and monosulpho-
anthracene scarcely soluble. After filtering and adding 30 per cent. of salt to the
filtered and concentrated liquor there is precipitated the mixture of the two
disulphonated acids corresponding to the disulphoanthraquinone acids a and B.
The precipitate crystallised again from the water is treated with barium chloride.
The two baryta salts are insoluble when cold, whilst the salt of the new acid is
alone soluble when heated; it can be got quite pure by a second crystallisation.
It is soluble in water at 100° C. from which it crystallises in long needles of
composition CH³ (SO³)³ Ba + 4 aq..
Cold, it is soluble to the extent of 9 gr. to a litre; it loses 2 aq. in a drying
apparatus; when heated to 110° to 120° C, it loses 4 aq, but the anhydrous salt

page_text: absorbs again 2 aq. when exposed to the air. The sodium, calcium and magnesium
salts dissolve easily, the lead salt less easily.
This new acid when oxidised by nitric or chromic acid produces B-disulpho-
anthraquinone which, fused with soda, gives pure anthrapurpurine, the triacetylated
derivative of which melts at 220° to 222° C.
The baryta salt, which is insoluble when hot, corresponds to a y-disulpho
anthracene acid, already described, which by oxidation and fusion gives flavo
purpurine. It is however produced in small quantity.
2. Instead of treating the mother liquor in a closed vessel, the mixture from the
sulphonation of the anthracene may be poured directly into boiling salt water and
filtered hot. The filtered mother liquor is bleached by lime, then evaporated till
the sea salt is crystallised. On cooling the product which collects is allowed to
dry in the air, and recrystallised in a small quantity of water.
The mixture of the disulpho anthracene acids thus obtained is converted into
baryta salts as set forth in 1, for effecting separation of the new anthra purpurine
acid.
The alizarine thus obtained possesses a high degree of purity.
This mono-sulpho-anthracene acid serves as primary matter, either for obtaining
alizarine or for the production of sulphonated acids of a higher degree of
sulphonation, which also serve for the preparation of corresponding anthracenic
coloring matters.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is:
The herein described manufacture of mono sulphonated anthracene acid by
treating anthracene heated above 100° C. with sulphuric acid of strength under
66° Bé.
ABEL & IMRAY,
Agents for the Applicant.