AN IMPROVED PROCESS AND APPARATUS FOR THE PRODUCTION OF ANILINE AND TOLUIDINE, AND OF COLORING MATERIALS THEREFROM
Year: 1882

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"AN IMPROVED PROCESS AND APPARATUS FOR THE PRODUCTION OF ANILINE
AND TOLUIDINE, AND OF COLORING MATERIALS THEREFROM." A communi-
cation from abroad by Edward D. Kendall, of Brooklyn, New York, United
States of America.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 25th January 1882.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS AND APPARATUS
FOR THE PRODUCTION OF ANILINE AND TOLUIDINE, AND OF COLORING MATERIALS
THEREFROM." A communication from abroad by Edward D. Kendall, of Brooklyn,
New York, United States of America.
This Invention has for its objects the production of aniline and toluidine from
corresponding nitro-derivatives of coal tar hydro-carbons; also the production of
various colouring substances from the aniline and toluidine to be used as dyes for
various purposes.
The said Invention consists chiefly in the process of subjecting the substances to
be treated, and thereby converted, to the action of the current either from a battery
or a dynamo electric generator by placing nitro-benzine, or a mixture of nitro-
benzene and nitro-toluine, in a porous cup or cell, and in a mixture of water and
sulphuric acid or saline water, and connecting the same with the negative electrode
of the electric circuit in such a manner that the water will be decomposed, and
the nascent hydrogen will combine with the nitro-benzine to form aniline or
mixed aniline and toluidine, as hereinafter described.
The said Invention further consists in subjecting the aniline or a mixture of
aniline and toluidine to the action of the positive electrode of the battery or electric.

page_text: circuit in the presence of sulphuric acid and water, whereby a color yielding solid
product will be precipitated or deposited upon the positive electrodes or in the cell,
as hereinafter described.
In order to accomplish these improvements I employ the well known electrolytic
cells with certain modifications, which also form part of this Invention, and are
illustrated in the accompanying Drawing, in which,
Figure 1 represents a perspective view of a cell with a porous cup therein, and
the carbons in proper position.
Figure 2 is a side elevation of the said porous cup with a carbon plate suspended
therein, and adjacent mechanism; and
Figure 3 is a perspective view drawn to a reduced scale of three of these cells
with their carbons and connections as they would appear in an organized series of
many cells for conducting the work on a large scale.
Any form of cell may however be used without departing from the principle of
this Invention, which, as above stated, consists partly in placing a certain quantity
of the nitro-benzine or mixed nitro-benzine and nitro-toluino in a porous cup or
cell, as at A, wherein is suspended the carbon or negative electrode B, which cell
and carbon are placed in a cell C that contains the positive electrodes or carbons D
and E suspended on opposite sides of the porous cup or cell A, as shewn in Figure 1.
The said porous cup contains a mixture (by fluid measure) of, say, one part of the
nitro-benzine or mixture of nitro-benzine and nitro-tuluine, and two parts of
ordinary sulphuric acid with thirty parts of water, in which is suspended the
carbon plate B attached to the negative pole of a battery or its equivalent, while
the other carbons D and E are suspended in a solution of acidulated water without
any of the nitrated hydro-carbons in contact with them; the result is that the
water is decomposed and the oxygen is allowed to escape, while the nascent-
hydrogen effects the reduction of the nitro-benzene or mixed nitro-benzene and
nitro-toluine so as to produce the corresponding amido-compounds.
But, as is well known, if the hydrogen is once set free it will not act on the
said nitrated hydro-carbons, which being of greater specific gravity than the dilute
acid, and insoluble therein, will not under ordinary circumstances be brought in
contact with the nascent hydrogen over the surfaces of the carbon-plate B; con-
sequently I suspend the carbon plate B or negative electrode in a screw-clamp F;
this screw-clamp is attached to the end of a pendulous lever G, supported upon a
pivot H, and connected by a link L to a crank pin M on a wheel, to which motion
may be given in any convenient manner, so that the carbon plate B may be gently
vibrated in the solution in the porous cup, and thereby effect the commingling of
the elements therein, and thus further ensure the contact of the said nitrated
bydro-carbon with the hydrogen at the instant of its production or separation from
the oxygen of the water.
To further ensure the said combination the carbon plate B may be covered with
cloth or a similar fibrous substance, the lower end of which is immersed in the
liquid nitrated hydro-carbons, and lifts the elements to be converted along the
surfaces of the carbon plate, where the hydrogen is being produced under the action
of the voltaic current; thus a more intimate relation may be established. Holes
may be formed in the cloth covering of the carbon, as shewn at O, to permit a free
circulation of the liquid in the porous cup.
It has been found that other acids and saline bodies may be used instead of the
sulphuric acid, but with less advantage.
While the conversion is in progress in the porous cup it has been found that the
aniline, or toluidine, or both united, in a mixture of sulphuric acid and water may
be placed in the cell C in contact with the positive electrodes or carbons D and E,
whereon will be precipitated variously colored solids from the aniline, or toluidine,
or both, from which by different chemical processes coloring substances may be
obtained, as, for example, a rose red similar to "rosaniline," a dark blue and
emerald green, a "eap green," and several shades of these colors; and thus, simul-
taneously with the production of the aniline or toluidine, the color yielding

page_text: substances may be obtained from them, and by the same battery or voltaic current,
or in the case of a dynamo machine without any increase of power.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. The method or process of producing aniline or toluidine from the corre-
sponding nitro derivatives of coal tar hydro-carbons by placing nitro-benzine or a
mixture of nitro-benzine and nitro-toluine in a porous cup or cell and in a
mixture of water and sulphuric acid, and connecting the same with the negative
electrode of an electric circuit, whereby the required conversion is effected, as above
set forth.
Second. The method of producing a color-yielding product from aniline or a
mixture of aniline and toluidine by placing the aniline or a mixture of the same
with toluidine in contact with the positive electrode of an electric circuit, and in
the presence of water and sulphuric acid, as above set forth.
Third. The combination with a porous cell or cup of the pendulous carbon plate
and the vibrating connections or their equivalents, as above set forth and for the
purpose specified.
Fourth. The combination of the pendulous carbon and the textile covering for
commningling the elements in the process of making aniline or toluidine, as above
set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-fourth day of January, in the year of our Lord
One thousand eight hundred and eighty-two.