Improvements in the Manufacture of Proto-sulphate and Per-sulphate of Iron.
Year: 1892

page_text: Date of Application, 13th Aug., 1892
Complete Specification Left, 13th May, 1893-Accepted, 17th June, 1893
Improvements in the Manufacture of Proto-sulphate and
Per-sulphate of Iron.
I, CHARLES DREYFUS of The Clayton Aniline Company Limited of Clayton
near Manchester in the County of Lancashire, Chemist do hereby declare the
nature of this invention to be as follows:-
In the purification of crude naphtha or light mineral oil or crude petroleum
sulphuric acid is used to take out impurities such as bases, tarry matters and the
like. This sulphuric acid so contaminated with organic and other impurities has
proved a bye-product difficult to dispose of.
The object of my invention is to utilize this acid product. According to my
invention I dilute the said product with water so as to form two distinct layers an
upper layer of a tarry nature and a lower layer which is a liquid of more or less
dark colour. This liquid contains besides a large proportion of free sulphuric
acid the sulphates of the bases and I use it for producing sulphate of iron or per-
sulphate of iron or basic per-sulphate of iron and I give this acid the naine of
diluted waste acid. For the purpose of producing the proto-sulphate of iron I
proceed as follows.-The quantities given I do not of course limit myself to but
they serve to indicate the proportions I consider advisable, about 2 cwt. of the
waste iron produced in the manufacture of aniline or other amido compounds are
put in a suitable vessel of a capacity of about 150 gallons and to this I add about
2 cwt. of the diluted waste acid above mentioned or a sufficient quantity to
neutralize the iron. The mass is then well stirred and after some time a violent
reaction takes place much heat being evolved and a dissolution of the iron takes place.
When the acid is properly neutralized the mass is allowed to settle, the upper
liquor is run into further settling tanks and the clear hot liquor is run into cooling
The residues of the settling
tanks where the sulphate of iron crystallizes out.
tanks can be used over again in the next operation.
To produce the per-sulphate of iron I proceed in a manner similar to that herein-
before described using along with the diluted waste acid above referred to, a
sulphuric acid resulting from the nitrification of organic substances such as
benzole toluole, carbolic acid, glycerine, cotton and the like, in fact in all operations
where a mixture of strong sulphuric and nitric acids is used for the purpose of
nitrifying organic substances. The bye-product being a weaker sulphuric acid than
the one originally used contaminated with more or less nitric and nitreous acids and
some organic matters. By the use of such waste acids containing nitric and
nitreous acids along with the diluted waste acid described above proto-sulphate of
iron is converted into a per-sulphate and should there not be enough oxidising
matters present for that purpose I add to the iron residue a sufficient quantity of
either nitrate of soda or any other nitrate or per-oxide of manganese or chlorate of
potash or any other suitable oxidising agent.
If it is required to produce the basic sulphate of iron in a solid state I take a
quantity (say 2 cwt.) of the iron residue from aniline works and about the same
quantity of a mixture of the dilute waste acid and waste acid from the nitrification
of organic substances as concentrated as possible and should it not contain sufficient
oxidising substances I add previously to the iron residue and sufficient proportion of
the oxidising substances mentioned above to convert the proto-sulphate into per-
sulphate of iron. If the acid has been of sufficient concentration the product of
the reaction is a solid per-sulphate of iron, and if there has been an excess of the
iron residue a solid basic per-sulphate of iron.

page_text: Should the iron residue not be dry enough or the sulphuric acid used. not con-
centrated enough the product obtained does not solidify after cooling but this
result can be obtained by evaporating.
Dated this 13th dar of August 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Proto-sulphate and
Per-sulphate of Iron.
I CHARLES DREYFUS of The Clayton Aniline Company Limited of Clayton
near Manchester in the County of Lancaster Chemist do hereby declare the
nature of my invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
In the purification of crude naphtha or light mineral oil or crude petroleum
sulphuric acid is used to take out impurities such as bases tarry matters and the
like.
This sulphuric acid so contaminated with organic and other impurities has proved
a bye product difficult to dispose of.
The object of my invention is to utilize this acid product. According to my
invention I dilute the said product with water (preferably for example in the
proportion of 25 to 50 parts by weight of water to 100 parts of the acid) so as to
form two distinct layers an upper layer of a tarry nature and a lower layer which
is a liquid of more or less dark colour and which is drawn off for use from the
bottom. This liquid contains besides a large proportion of free sulphuric acid the
sulphates of the bases and I use it for producing proto sulphate of iron or per-
sulphate of iron or basic per-sulphate of iron and I give this acid the name of
diluted waste acid. For the purpose of producing the proto-sulphate of iron I
proceed as follows. The quantities given I do not of course limit myself to but
they serve to indicate the proportions I consider advisable.
About 2 cwt. of the waste iron produced in the manufacture of aniline or other
amido compounds are put in a suitable vessel of a capacity of about 150 gallons and
to this I add about 2 cwt. of the diluted waste acid above mentioned or a sufficient
quantity to neutralize the iron. The mass is then well stirred and after some time
a violent reaction takes place much heat being evolved and a dissolution of the iron
takes place. When the acid is properly neutralized the mass is allowed to settle,
the upper liquor is run into further settling tanks and the settled hot liquor is run
into cooling tanks where the sulphate of iron crystallizes out. The residues of the
settling tanks can be used over again in the next operations.
To produce the per-sulphate of iron I proceed in a manner similar to that
hereinbefore described using along with the diluted waste acid above referred to
any proportion of a sulphuric acid resulting from the nitrification of organic
substances such as benzole, toluole carbolic acid, glycerine, cotton and the like in
fact in all operations where a mixture of strong sulphuric and nitric acids is used
for the purpose of nitrifying organic substances (the bye product being a weaker
sulphuric acid than the one originally used contaminated with more or less nitric
and nitrous acids and some organic matters). By the use of such waste acids con-
taining nitric and nitrous acids along with the diluted waste acid described above
proto-sulphate of iron is converted into a per-sulphate and should there not be
enough oxidising matters present to convert all the proto-sulphate of iron into per-
sulphate of iron I add to the iron residue a sufficient quantity of either nitrate of
soda or any other nitrate or per-oxide of manganese or chlorate of potash or any
other suitable oxidising agent, the quantity necessary being calculated by ordinary.
analytical methods.
If it is required to produce the basic per-sulphate of iron in a solid state I take a

page_text: quantity (say 2 cwt.) of the iron residue from aniline works and about the same
quantity (2 cwt.) of a mixture in any proportion of the dilute waste acid and waste
acid from the nitrification of organic substances as concentrated as possible and
should it not contain sufficient oxidising substances I add previously to the iron
residue a sufficient proportion determined by analysis of the oxidising substances
mentioned above to convert the proto-sulphate into per-sulphate of iron. If the
acid has been of sufficient concentration say at 120 Twaddle and upwards the
product of the reaction is a solid per-sulphate of iron and if there has been an
excess of the iron residue a solid basic per-sulphate of iron.
Should the iron residue not be dry enough or the sulphuric acid used not
concentrated enough the product obtained does not solidify after cooling but this
result can be obtained by evaporating.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In the manufacture of proto-sulphate of iron or per-sulphate of iron or basic
per-sulphate of iron treating waste iron produced in the making of aniline or other
amido compounds with what I have called diluted waste acid substantially as
hereinbefore described.
2. The utilization of sulphuric acid which has been used for removing impurities
from hydrocarbons, by diluting the said acid so as to obtain what I have termed
diluted waste acid and the employment of this acid in the manufacture of proto-
sulphate of iron or per-sulphate of iron or basic per-sulphate of iron substantially
as hereinbefore described.
3. The manufacture of per-sulphate of iron or basic per-sulphate of iron by the
treatment of waste iron produced in the manufactuae of aniline or other amido
compounds with what I have termed diluted waste acid and with waste acid
resulting from the nitrification of organic substances with or without the addition
of further oxidising materials substantially in the manner hereinbefore described.
Dated this 13th day of May 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.