Production of Amorphous Carbon from Acetylene.
Year: 1898

page_text: Production of Amorphous Carbon from Acetylene.
I, LOUIS JOSEPH ERNEST HUBOC, of Le Raincy, department of Seine and Oise,
France, Engineer, do hereby declare the nature of this invention to be as
follows;
It is known that acetylene gas decomposes into its elements, carbon and
hydrogen, under a temperature which Mr. Lewes places at 780° centigrade.
The experiments of Messrs Barthelot and Vieille have shown that it decom-
poses, when compressed, by the exciting action of a percussion priming, by an
induction spark, or by simple ignition by means of a metallic wire made incan-
descent by an electric current.
It is also known that the combustion of acetylene gas can give a deposit of
amorphous carbon when the proper proportion of air is arranged for that com-
bustion, so as not to produce the complete oxidation of that gas.
In this latter case, the carbon obtained is always of a black more or less
reddish in consequence of the formation of polymeres of acetylene and of their
oxidation by the flame. On the other hand, the incomplete combustion of the
acetylene gas produces a loss of carbon and a decreased return which, on account
of the cost price of acetylene, is far from being unimportant.
On the contrary, the entire return from acetylene of pure carbon is say
the 923% by decomposing it out of the air by the action of electricity or of
heat or of chemical agents.
The carbon thus formed is pulverizable, voluminous and purer than any other
black hitherto known. The blacks of commerce: blacking, German black,
Spanish black, peach black, lamp black, petroleum black, etc. are not in fact
formed of pure carbon but of carbon mixed with resinous or bituminous sub-
stances, carburet of hydrogen and with salts, and they have to be refined generally
by calcination and washing
On the other hand, by quick or slow decomposition of acetylene gas compressed
or not, under the action of a sufficient source of energy such as electric or
calorific energy, a black is obtained which is characteristic and of special and
superior quality to the existing blacks.
This is what we have recognized in trying this black from a commercial point
of view; we have taken note that it possesses a new characteristic which we
wish to guarantee by the present application for a patent.
This new black we call
acetylene black" to indicate its origin and to distin-
guish it from other blacks. We are for the first time applying a product of an
industry in which it has not yet been used, by using materials for its production

page_text: different from those used for similar products and it is this priority of its applica-
tion to the manufacture of black that we claim for our acetylene black."
66
For example, by compressing acetylene gas under 2 or 3 atmospheres, and
exploding it by electricity, the final pressure of the hydrogen resulting from the
decomposition does not exceed 25 atmospheres. All the return of this acetylene
is immediately obtained in acetylene-black, and that without fear of explosion
by employing steel receivers, such as those constantly manufactured, capable of
resisting 200 atmospheres and more.
For this new black has the advantage of being manufactured at the first
touch and of being ready for use at once. It is one of the purest carbons in
existence; it possesses a tenuity and lightness which are peculiar, is oily, velvety,
and a fine free black; it is a special and quite peculiar black.
It mixes well with oils, essences, albumen, glue, dextrine, glucose, water, etc.
Ground with oil, for instance, it leaves no lumps and spreads very evenly.
Black paint thus produced and exposed to the air dries without change of tone
or cracking.
We have tried it for making inks. Using it, for instance, for engraving, we
have obtained very clear proofs: this "acetylene black" preserves all the details
and half tints, while the other blacks give heavier tints which often require
softening.
Mixed with water and glue, it gives a deep black, velvety and luminous, so
to speak, and with an incomparable richness of tone.
Mixed with oil and essence, it gives a pigment which, when varnished, is
capable of replacing Japan varnish.
Our researches have demonstrated to us that this acetylene black is destined
to be advantageously employed for superior inks, and in particular, Chinese ink
(Indian ink), for printing, lithographic and autographic inks, for etchings, helio-
graphs, carbon photography for oil colours, essence colours and water colours,
for varnishes and lacquers, for printing on cloth, and generally for all applica-
tions of blacks already known.
The industrial advantages of our application of it rest on the fact that acety-
lene gas is the gas which is richest in carbon, that it is, in fact, in a measure,
pure carbon, and that we obtain its full return in marketable black.
Dated this 23rd day of March 1898.
L. DUVINAGE,
Patent Agent,
8. Rue des Princes, Brussels, Belgium.
COMPLETE SPECIFICATION.
Production of Amorphous Carbon from Acetylene.
I, LOUIS JOSEPH ERNEST HIBOU, of Le Rainey, department of Seine and Oise,
France, Engineer, 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 production of amorphous carbon from acetylene.
I manufacture commercial black or amorphous carbon, I term "acetylene
black by decomposing acetylene in closed vessels and sheltered from the influence
of air, by means of a sufficient source of energy, in taking advantage of the fact
that acetylene is endothermic.
The method of producing amorphous carbon, as hereinafter pointed out, is
entirely different from those hitherto employed or proposed for producing indus-

page_text: rial black and which consist in incompletely burning hydrocarbons containing
suitable proportion of carbon. Compared to these methods, my improved
method is found of the following advantages:
Indeed the incomplete combustion of hydrocarbons being of course effected
with the action of air, produces condensated compounds and at the same time
the oxidation of the precipitated excess of carbon. Thus lamp black or soot is
obtained which is not uniformly black and has a fawn-coloured tone due to
yellow bodies produced. Besides, a considerable part of said hydrocarbons are
burnt, that is, converted to gaseous products (carbonic gas or the like), whereby
the production of carbon will be correspondingly lessened. This is a disadvan-
tage which, for industrial purposes, constitutes a considerable. loss of produce:
by reason of this loss the method of burning with the action of air may even
become inapplicable if acetylene, that is, a comparatively expensive gas, be in
question as in this case.
Instead of burning acetylene and obtaining a useless flame and lamp black or
soot by the action of air, it is always preferable to take advantage of the fact
that acetylene is endothermic and easily decomposed, when sheltered from air, by
the action of a suitable energy.
By this method the industrial application of which I claim, I obtain a com-
plete produce of black that is, the whole of 92.3% of carbon, with acetylene in
a pure state.
The carbon will be free from any secondary products and instantaneously
obtained in a pure state, without it being necessary to purify the same by
calcination or washing.
There is no lamp-black or soot but carbon in a pure state the composition of
This is an essential feature on which I must
which will always be the same.
insist, for it allows of manufacturing commercial products and particularly inks,
the quality of which will always remain constant, which is not possible with
ordinary blacks produced by the incomplete combustion of hydrocarbons, when
the same have not undergone a sufficient purification.
My improved method is as follows: I introduce, into a hermetically closed
vessel containing no air, acetylene which is compressed to a pressure beyond two
atmospheric pressures and capable of being raised to ten and more atmospheric
pressures with a sufficiently strong vessel. Now I produce the explosion of this
gas, sheltered from the action of air, by means of an incandescent tube or wire or
by electricity, and in general, by means of a source of electric or calorific energy
capable of decomposing acetylene gas. The latter will be instantaneously decom-
posed and converted to: 1, amorphous carbon settling in bulk within the vessel
and constituting what I term "acetylene black," and 2, hydrogen I collect as
subproduct to be utilized as presently described. One part of the hydrogen may
be left within the vessel, for the purpose of preventing air from entering said
vessel and diminishing the energy of the next reaction.
a
If, in fact, after a preceding operation, hydrogen at the atmospheric pressure
be left within the vessel and fresh acetylene gas compressed to four atmospheric
pressures introduced for the next operation, the closed vessel will contain a
mixture of hydrogen and % acetylene gas, the latter being decomposed by
less vehement energy than if acetylene only be employed. The remaining of
the collected hydrogen is utilized for the motor of the compression pump or for
any other purpose.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The novel utilization of "acetylene black" produced in closed vessels without
the action of air, as a marketable black capable of being used in the same ways
as the blacks already known.
manufacture (with a view to this utilization) of " acetylene

page_text: black" instantaneously produced by decomposing acetylene gas in closed vessels
and sheltered from air, by the action of a suitable source of electric or calorific
energy.
3. The utilization of hydrogen produced by said manufacture, for preventing
air from entering the vessel and diminishing the energy of the next reaction, the
excess of hydrogen remaining as subproduct to be employed for any purposes to
which hydrogen is destined.