Improvements in and relating to the Manufacture of Paints, Sulphuric and Sulphurous Acid from Protosulphate of Iron.
Year: 1893

page_text: Date of Application, 28th Feb., 1893
Complete Specification Left, 28th Nov., 1893-Accepted, 30th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Manufacture of Paints,
Sulphuric and Sulphurous Acid from Protosulphate of Iron.
I MICHEL NICHOLAS D'ANDRIA of 6 Frogmore Terrace Chester Road
Stretford in the County of Lancaster, Manufacturing Chemist, do hereby declare
the nature of this invention to be as follows:-
My invention relates to the manufacture of red oxide paint from protosulphate
of iron by the well known process of dry distillation, utilising at the same time the
sulphuric and sulphurous acid evolved in the process in a more rational manner than
has been done heretofore.
In carrying out my invention, I connect the retorts in which the dry distillation
of the protosulphate of iron is carried out with a conduct pipe which is in direct
communication with an ordinary sulphuric acid chamber which at the same time is
employed for the manufacture of sulphuric acid by the ordinary process. In the
process of the dry distillation of the protosulphate, anhydrous sulphuric and
sulphurous acid are given off, which through the above mentioned pipes, escape
into the sulphuric acid chamber. The anhydrous sulphuric acid is at once absorbed
by the weak "chamber acid" which is thus concentrated and obtained of consider-
ably higher strength than usual, whereby the cost of the subsequent concentration
of the chamber acid is materially lessened.
The sulphurous acid, on the other hand is in due course oxidised in the chamber
into sulphuric acid by the nitrous acid gas present. Or I may arrange the pipes
which are conducting the sulphuric and sulphurous acid from the retorts to the
chamber, in such a manner, that the sulphuric acid is condensed or liquified before
entering the chamber, then the sulphurous acid can be separated from the sulphuric
acid, and is then most conveniently employed for the manufacture of liquid
sulphurous acid, anhydrous (liquified) sulphurous acid, also sulphites and
bisulphites.
In this manner, I completely recover and utilise the whole of the sulphuric acid
contained in protosulphate of iron.
3000
COMPLETE SPECIFICATION.
Improvements in and relating to the Manufacture of Paints,
Sulphuric and Sulphurous Acid from Protosulphate of Iron.
I MICHEL NICHOLAS D'ANDRIA of 6 Frogmore Terrace Chester Road
Stretford in the County of Lancaster Manufacturing Chemist, 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 :-
My invention relates to the manufacture of red oxide paint from protosulphate
of iron by the well known process of dry distillation, utilizing at the same time the
sulphuric and sulphurous acid evolved in the process, in a more rational manner
than has been done heretofore.
In carrying out my invention, I connect the retorts or the muffle furnace in
which the dry distillation of the proto-sulphate of iron is carried out with a
conduct pipe which is in direct communication, with an ordinary sulphuric acid
chamber which at the same time is employed for the manufacture of sulphuric acid
by the ordinary process.

page_text: In the process of the dry distillation of the proto-sulphate of iron, anhydrous
sulphuric and sulphurous acid are given off, which through the above mentioned
pipes escape into the sulphuric acid chamber. The anhydrous sulphuric acid is at
once absorbed by the "chamber acid" which is thus concentrated and obtained of
considerably higher strength than usual whereby the cost of the subsequent con-
centration of the "chamber acid" is proportionately lessened. The sulphurous
acid on the other hand, is in due course oxidised in the chamber into sulphuric acid,
by the nitrous acid gas present. Or I may arrange the pipes which are conducting
the sulphuric and sulphurous acid from the retorts or from the muffle furnace to
the chamber in such a manner, that the sulphuric acid is condensed or liquified
before and without entering the chamber. Then the sulphurous acid can be
separated from the sulphuric acid and is then most conveniently employed for the
manufacture of liquid sulphurous acid, anhydrous (liquified) sulphurous acid, also
sulphites and bisulphites, but instead of this, it may as above proposed, be sent
into the sulphuric acid chambers.
In this manner, I completely recover and utilize the whole of the sulphuric acid
contained in the proto-sulphate of iron.
Having now particularly described the nature of my invention and in what
manner the same is to be performed, I declare that what I claim is
1. The utilisation of sulphuric acid and sulphurous acid, which are obtained as
by-products in the manufacture of red oxide paints from ferrous sulphate, for the
manufacture of sulphuric acid, in the manner substantially set forth above.
2. The recovery as separate products of anhydrous or fuming sulphuric acid and
sulphurous acid as by-products of the manufacture of red oxide paint from
ferrous sulphate, by the use of a condensation arrangement essentially of the kind
set forth above.
Dated this 27th day of November 1892