A Process for the Application of Iron Residues which result from the Reduction of Organic Nitrocompounds.
Year: 1890

page_text: Date of Application, 9th June, 1890
Complete Specification Left. 9th Mar., 1891-Accepted, 11th Apr., 1891
PROVISIONAL SPECIFICATION.
A Process for the Application of Iron Residues which result from
the Reduction of Organic Nitrocompounds.
I, THEODOR PETERS, of Chemnitz, in the Kingdom of Saxony, Manufacturing
Chemist, do hereby declare the nature of this invention to be as follows:-
The iron mud residues are amongst the chief bye or waste products in the
manufacture of aniline, naphthylamine, phenylendiamine toluylendiamine and other
organic amido-compounds. They result from the reduction of nitro-compounds.
The mud contains about 80 per cent. of sesqui-oxide. On account of its weight,
and the large quantity in which it is produced, it is not easily transportable.
That no one has hitherto used this mud to much advantage is doubtless because of
the large proportion of carbonaceous matter which it contains and to a less degree
on account of its richness in chloride of calcium which interferes with the action of
sulphuric acid.
I have discovered a process in which the iron mud is so treated, that the oxygen
in the same is utilised and a product obtained, which is much used as a mordant in
dyeing and as a disinfectant.
This product is at present obtained in rather a costly manner by oxidising iron
vitriol with nitric acid. My invention includes the production of a product in a
solid form.
The best process for use in aniline works is as follows:-
The iron mud from the reduction apparatus is allowed to settle and a liquid
containing chloride of calcium separates out.
About 200 k. of the paste remaining, which preferably should not contain more
than 20 per cent. of moisture is put into a vessel of about 1200 litres capacity and
It is best to use 57° Beaume
100 k. of moderately dilute sulphuric acid is added.
waste acid from the apparatus from the nitration of the aromatic hydrocarbons,
and add an equal weight of water i.e. about 100 litres.
The mass is then stirred with wooden poles and after some time a quick reaction
is set up accompanied by foaming and much heat, sufficient to cause liquification of
the mud and also as the temperature rises considerably over 100° C. the destruction
of the greater part of the organic matter remaining in the mud.
After frequent stirring the mass is left some time to itself, it often rises nearly to
the top of the tank, but gradually recedes and the foam disappears.
After a few hours rest in the preparing tanks, the turbid brown liquor is removed
into settling tanks, and a clear dark liquid of about 40° Béaume separates out.
After evaporating the latter to about 50° Béaume and letting it cool it is ready
for use.
The residues of the settling tanks are collected and a further quantity of
liquor is obtained from them which is about 10° Béaume stronger than that before
obtained.
The residues are then stirred with water and a liquor of about 30° Béaume is
again obtained.
It is best not to concentrate this, but in charging the tanks to use it in place of
a corresponding amount of water. The residues still contain iron oxide besides
gypsum
be again treated.
and may
The iron solution obtained contains some proto-oxide, but a product quite free
from it may be obtained by adding either at the beginning in filling the tanks or
later in concentrating the liquor a suitable quantity of dilute nitric acid or other
like oxydising matter.

page_text: For this purpose the weak acid from the manufacture of nitric acid, which passes
over towards the end of the process may be advantageously used.
Working with the above given quantities, there is an excess of iron which
ensures a product as neutral as possible, and therefore fit for dye purposes.
If the iron mud containing 20 per cent. of moisture be used without the addition
of water, but otherwise using the same proportions, a liquor of 50° Béaume is
directly obtained. On account of its high specific gravity, the settling of suspended
particles is noticeably slower.
The production of the basic salt in a solid, but easily soluble state convenient
for transport, has heretofore been attempted by evaporating the iron mordant
solution, but hitherto with small success, as when concentrated decomposition of
the basic salt in the solution sets in.
By using the before mentioned iron mud the production of such a product is
possible. About 100 k. of the mud with the chloride of calcium liquor adhering
or of purified dry mud is taken, and about the same quantity of fairly concentrated
sulphuric acid is stirred with it; waste acid of aniline works may advantageously be
used. The mixture solidifies to a mass as hard as glass which can be easily
pulverised. If the same because of the mud being a little too moist, or the
sulphuric acid not being concentrated enough, does not solidify after cooling it may
be made to do so by heating on a hearth by stirring the pulverised product with
the necessary quantity of water a solution of 50° Beaume is easily obtained.
This is the state in which the mordant is now known in the market.
Thus I utilise both iron residues and waste sulphuric acid and nitric acid in the
production of a marketable product, and this I do at little cost.
Dated this 9th day of June 1890.
CARPMAEL & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION,
A Process for the Application of Iron Residues which result from
the Reduction of Organic Nitrocompounds.
I, THEODOR PETERS, of Chemnitz, in the Kingdom of Saxony, 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 :-
The iron mud residues are amongst the chief bye or waste products in the
manufacture of aniline, naphthylamine, phenylendiamine, toluylendiamine and
other organic amido compounds. They result from the reduction of nitro-
compounds. The mud contains about 80 per cent. of sesqui oxide. On account
of its weight, and the large quantity in which it is produced, it is not easily
transportable.
That no one has hitherto used this mud to much advantage is doubtless because
of the large proportion of carbonaceous matter which it contains and to a less
degree on account of its richness in chloride of calcium which interferes with the
action of sulphuric acid.
I have discovered a process in which the iron mud is so treated, that the oxygen
in the same is utilised and a product obtained, which is much used as a mordant
in dyeing and as a disinfectant.
This product is at present obtained in rather a costly manner by oxidising iron
vitriol with nitric acid. My invention includes the production of a product in a
solid form.
The best process for use in aniline works is as follows:-
The iron mud from the reduction apparatus is allowed to settle and a liquid
containing chloride of calcium separates out.”

page_text: than 20 per cent. of moisture is put into a vessel of about 1200 litres capacity and
100 k. of moderately dilute sulphuric acid is added. It is best to use 57° Béaume
waste acid from the apparatus from the nitration of the aromatic hydrocarbons, and
add an equal weight of water i.e. about 100 litres.
The mass is then stirred with wooden poles and after some time a quick reaction
is set up accompanied by foaming and much heat sufficient to cause liquification
of the mud and also as the temperature rises considerably over 100° C. the
destruction of the greater part of the organic matter remaining in the mud.
After frequent stirring the mass is left some time to itself, it often rises nearly
to the top of the tank, but gradually recedes and the foam disappears.
After a few hours rest in the preparing tanks, the turbid brown liquor is
removed into settling tanks, and a clear dark liquid of about 40° Béaume separates
out.
After evaporating the latter to about 50° Béaume and letting it cool it is ready
for use.
The residues of the settling tanks are collected and a further quantity of
liquor is obtained from them which is about 10° Béaume stronger than that before
obtained.
The residues are then stirred with water and a liquor of about 30° Béaume is
again obtained.
It is best not to concentrate this, but in charging the tanks to use it in place of
a corresponding amount of water. The residues still contain iron oxide besides
gypsum and may be again treated.
The iron solution obtained contains some proto-oxide, but a product quite free
from it may be obtained by adding either at the beginning in filling the tanks or
later in concentrating the liquor a suitable quantity of dilute nitric acid or other
like oxydising matter.
For this purpose the weak acid from the manufacture of nitric acid, which passes
over towards the end of the process may be advantageously used.
Working with the above given quantities, there is an excess of iron which ensures
a product as neutral as possible, and therefore fit for dye purposes.
If the iron mud containing 20 per cent. of moisture be used without the addition
of water, but otherwise using the same proportions, a liquor of 50° Béaume is
directly obtained. On account of its high specific gravity, the settling of suspended
particles is noticably slower.
The production of the basic salt in a solid, but easily soluble state convenient
for transport, has heretofore been attempted by evaporating the iron mordant
solution, but hitherto with small success, as when concentrated decomposition of the
basic salt in the solution sets in.
By using the before mentioned iron mud the production of such a product is
possible. About 100 k. of the mud with the chloride of calcium liquor adhering
or of purified dry mud is taken, and about the same quantity of fairly concentrated
sulphuric acid is stirred with it; waste acid of aniline works may advantageously
be used. The mixture solidifies to a mass as hard as glass which can be casily
pulverised. If the same because of the mud being a little too moist, or the
sulphuric acid not being concentrated enough, does not solidify after cooling, it
may be made to do so by heating on a hearth. By stirring the pulverised product
with the necessary quantity of water a solution of 50° Béaume is easily obtained.
This is the state in which the mordant is now known in the market.
Thus I utilise both iron residues and waste sulphurie acid and nitric acid in the
production of a marketable product, and this 1 do at little cost.
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 :-
The process consisting in the treatment substantially in the manner described of

page_text: the iron residues resulting from the reduction of organic nitro compounds; thereby
obtaining a solution or a solid product suitable for use as a mordant and also as a
disinfectant.
dated thin fth love of Manch 1901