Improvements in or relating to the Treatment of the Acid Residuums or Tars Resulting from the Refining of Mineral Oils by Concentrated Acids.
Year: 1888

page_text: Date of Application, 14th Jan., 1888
Complete Specification Left, 14th Nov., 1888
Complete Specification Accepted, 21st Dec., 1888
Improvements in or relating to the Treatment of the Acid
Residuums or Tars Resulting from the Refining of Mineral
Oils by Concentrated Acids.
I, CHARLES RAVE of Malines, in the Kingdom of Belgium, Chemist, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the treatment of the residuum of mineral oils and has for
its object the conversion into new products of the acid residues or tars derived from
the refining of the said mineral oils, especially petroleum by concentrated sulphuric
acid and the various applications of the products so obtained.
In the treatment which mineral oils undergo there is besides the well known
distillation, an indispensable operation common to almost all fatty substances, this is
the refining or purification which consists in the beating of the oils with concen-
trated sulphuric acid. This operation has for its object to carbonize or carry away
the organic materials in suspension or in solution in the oils, so as to separate them
in the form of a black residue or tar strongly charged with acid hence its name
"acid tar." Without inquiring into the composition of this body which chemistry
has not yet determined, I have made it a study with a view to its application to
industrial purposes. This question is the more important because the said residue is
cumbersome, of little value, and amounts to as much as a quarter of the total production
of the petroleum.
In many petroleum works or refineries, acid tar is burnt, being mixed with
neutralizing materials and coal; but in this case the value which it acquires does not
exceed that of bad coal.
The regeneration of sulphuric acid has been tried but this operation does not result
in any profit by reason of the low price of sulphuric acid.
According to the said invention the acid tar such as results from refining as above
described is kneaded with waste metal such as iron, copper, zinc or other bases which
are divided as much as possible but preferably with iron, by reason of the valuable
products that are derived therefrom.
.

page_text: After a more or less prolonged contact, the mass formed by the decomposition of
the iron or other metal and of the sulphuric acid is introduced into heated receptacles,
water is added thereto, and the salts which are formed by this double decomposition
dissolve and separate from a black mass that comes to the surface. This black mass is
composed of organic materials separated from their acid compound and which are
transformed into a neutral product having the appearance and all the properties of the
best purified bitumens.
The lixiviating water containing the salts, such as sulphate of iron or other salts in
solution is decanted into reservoirs where the salts crystallize. Thus all the acid
employed in the purification of the oil is transformed to advantage.
The separated bitumen is washed in order to remove all traces of salts, and is then
put into boilers in which it is concentrated to the desired consistency. The bitumen
thus'obtained is purer than the refined bitumens of ordinary manufacture. It is free
from foreign substances, and may be used for any purpose to which natural bitumens
are applicable. I give this bitumen the name of "Mineral Caoutchouc Bitumen " by
reason of its analogy with natural caoutchouc and its malleable and elastic
properties.
The body obtained under the conditions hereinbefore specified possesses other
properties than the bitumen of ordinary manufacture. Being the result of a com-
bustion, of the carrying away or of a sulphuric combination, treated under special
conditions of decomposition in contact with metallic bodies, the mineral caoutchouc
bitumen is a new body possessing special properties. This has been determined after
numerous trials that have shown the nature and qualities of this product the principal
applications and the transformations, beyond its employment of bitumen that I have
set forth and reserved. The mineral caoutchouc bitumen melted in iron boilers is
mixed with limestone, lime or chalk, and with oxygenated organic materials preferably
sawdust, the proportions of this mixture may vary but as an average proportion 10 to
20 per cent. of limestone and 30 to 40 per cent. of sawdust may be mentioned.
After having been intimately mixed and well heated, a pasty mass is obtained
which solidifies by cooling; the said mass can then be put into suitably shaped moulds
as desired.
The above mixture constitutes a fuel of the very best quality, rich in gas, and
caloric. This fuel or petroleum coal burns in any fire place. Moreover it does not
melt when burning, and produces only a small quantity of ashes. The said fuel or
petroleum coal is especially adapted for industrial and domestic heating purposes, for
the manufacture of rich gas, and the like. The said petroleum coal will moreover be
of great commercial value in countries where petroleum is found and worked, and
where solid fuel is not found or is imported at great expense.
The mineral caoutchouc bitumen dissolves in light oils-naphtha from petroleum
being its natural solvent-forms an excellent varnish or coating material that is
absolutely waterproof, unaffected by air, humidity or the like. This coating does
not crack, it has a remarkable adhesive power upon any bodies to which it is applied
as a coating to preserve them, such as metals, wood, paper and the like. The said
mineral caoutchouc bitumen combines in any proportions with rosin, wax, pitch and
the like, and forms different compounds.
Employed alone or combined with sulphur as vulcanized caoutchone, mineral
caoutchouc bitumen in the solid or fluid state is a body that is unaffected by acid
or alkaline baths whatever be the duration of the contact and the strength of the
bath. This property, which will be understood by taking into consideration the
origin of the mineral caoutchouc bitumen renders it fit to be used for the preservation
of acid and alkaline baths such for instance as electric accumulators and piles and for
other industrial applications. I give the mineral caoutchouc bitumen prepared for
this purpose the name of "Ebonic Coating."
By means similar to those employed in the manufacture of papier maché, statuary,
pasteboard and leather, I form very solid plates of mineral caoutchouc bitumen,
adapted to the manufacture of primary and secondary piles and the like, for replacing
the ebonite employed for this purpose.

page_text: The mineral caoutchouc bitumen is especially adapted for application to electrical
purposes, it being a perfect insulator, superior by reason of its unchangeableness, to
caoutchouc or guttapercha. The importance of this quality will be readily understood
as affecting its employment for electric accumulators and piles as well as for insulating
plates, electric wires, cables, connections for joints and the like.
Subjected to distillation, the mineral caoutchouc bitumen is divided into various
liquid hydrocarburets approaching the mother product from which they have been
derived. First are obtained methylic or ethylic alcohols, then naphtha, after this a
heavier oil adapted to be used for lighting and finally paraffin oils. The proportion
of the liquid products obtained is on the average 50 per cent. of the distilled mineral
caoutchouc bitumen. These oils are capable of being transformed into colouring
matters, and are adapted for lighting and for the manufacture of rich gas.
After the distillation of the mineral caoutchouc bitumen at a high temperature there
remains in the retort a product having the appearance and lustre of a grey metal very
hard and capable of scratching glass. This product to which I give the name of
of "Metallic Carbon" constitutes an excellent charcoal for piles, crayons, microphones
and the like; and is also a very good conductor.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Filing Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to the Treatment of the Acid
Residuums or Tars Resulting from the Refining of Mineral
Oils by Concentrated Acids.
I, CHARLES RAVE of Malines in the Kingdom of Belgium, 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 tars are generally sub-products of various manufactures among others, the following.
Tars which are formed in the manufacture of coal gas, gas or oil from schists, boghead,
cannel coal, gas from mineral oils and various animal and mineral matters, the acid
tars formed from the purification of mineral oils and others, the tars produced direct
from the distillation of coals, schists, boghead and other products giving tars in the
course of their distillation.
Treatment: The purification of the fatty bodies is generally made by concentrated
sulphuric acid which brings down in tarry form the organic matters. The mineral
oils, petroleum and schist oil for lighting and lubrication, are above all submitted to
an energetic treatment with concentrated sulphuric acid. This is an abundant source
of sub-products to utilize. These acid tars are of little value and are produced in
considerable quantity at the places of extraction and treatment of petroleum. Besides
the resource of acid tars that I have already indicated there is that of neutral tars
which are formed in abundance and which will be described generally further on.
I treat the neutral tars by concentrated sulphuric acid as if they had been formed
by the purification of oil. By this treatment the fatty matters separate themselves
intact from the organic (attacked and preciptated by the sulphuric acid).
In describing the various qualities and sources of the tars utilized by this process it
should be understood that the treatment cannot be uniform and it must vary according
to the nature of the tar treated but the principie of treatment remains the same.
Take
the acid tars such as present themselves as the residue of purification by concentrated
sulphuric acid, or by treating the neutral tars by the same acid; or the acid tars from
the purification of light or heavy mineral or petroleum oils. I treat these residues by
mixing them with iron turnings or filings with the addition of water. The acid of the
tars combines with the iron to form a sulphate. When the neutralization of tar is
complete the mixture is washed with water in steaming apparatus or by naked fire
heat. The sulphate formed dissolves entirely, the solution is caused to run out hot into
reservoirs where the sulphate crystallizes. The mass of bituminous matter obtained is
washed one or several times to take away the traces of sulphate which would otherwise
remain combined with it, and it is then introduced into kettles heated by naked fire
heat where the water which remains in the mass is evaporated and it is concentrated to
any desired consistence according to what it is to be applied for. If the kettles be
closed vessels the matters distilled off can be condensed and utilized. The acid tar is
thus transformed into a neutral bitumen having all the properties of natural bitumens

page_text: of the best kinds and having also properties which these latter do not possess as will
be indicated further on. In the purification of naphtha and of illuminating oil by
sulphuric acid there is formed generally a very fluid acid tar which it is impossible or
at all events very difficult to bring to the desired consistency by the treatment which
has just been indicated. For these tars the treatment is modified and is replaced by
the following: The tarry precipitate which is formed by the acid purification is a
carburetted body which reduces the sulphuric acid. In heating it, it disengages the
sulphuric acid in abundance.
In introducing this acid tar into a retort and directing the gaseous disengagement
upon a base or a solution of a base, such as 'soda or potash one forms a sulphite
or bisulphite of the base employed. This treatment puts a notable value upon all
the sulphuric acid contained in these liquid tars of which the petroleum refineries
in Belgium have great trouble to get rid of for nothing. The solid part of the tar.
remains behind in the retort.
Treatment of neutral tars: These tars are introduced into the receptacles where they
are heated at will. Concentrated sulphuric acid is now mixed little by little, care
be taken to render the mixture intimate by rapid kneading; any well-known
mechanical kneaders or mixers can be employed for this purpose. The proportions of
acid vary according to the nature of the tars to be treated, the conditions of tempera-
ture varying equally. If the tar be thick it can be heated to liquefy it sufficiently to
be able to treat it. If on the contrary it be fluid, heating is useless. In proportion
as the mixture of tar and acid is made the parts attackable by the sulphuric acid
separate themselves from the parts not capable of being acted upon by acid. These
latter are the oils containing hydrocarbons of different densities that are separated by
fractional distillation. If the tars thus treated are obtained from gas-coal there is
obtained directly without distillation, light and heavy oils without having to distil all
the matters of tar as ordinarily practised for to obtain six to ten per cent. of benzine
which they contain. This result is important to notice. It opens a new way for the
economical separation of the hydrocarbon oils which give birth to artificial coloring
matters. The matter separated by the acid is treated by the iron and the water as I
have already indicated for the treatment of acid tars. The sulphate of iron formed is
crystallized, the mass is washed and evaporated until it is deprived of water. A very
dense and brilliant bitumen is thus obtained to which the name of "vulcanized
bitumen" has been given. This bitumen follows the nature of the tar from which it
has been extracted. It is sometimes very dry and very tough. In this case it
redissolves in the heavy oil which has been withdrawn from it by the acid treatment.
This is the best, if not the only solvent of this vulcanized bitumen. By this treatment
there is given to the bitumen the malleability which is desired without it losing its
other good qualities.
In a preceding paragraph it is mentioned that the oils separated by the acid ought
to be treated by fractional distillation in order to divide them into light and heavy oils.
The light oils having a density of 870 as a mean-besides the benzine which they
contain when the tars treated contain it-find important applications principally the
manufacture of mineral oils for painting. This application is of great importance the
paint surfaces obtained by the employment of these oils are economical and resisting,
and their employment is assured upon a great scale. The heavy oils separated from
the light oils have a density between 950 and 970. These oils are useful for
mechanical lubrication and serve for the solution of vulcanized bitumen as has already
been indicated above.
It may be remarked that the bitumen extracted from mineral petroleum oils does
not mix with the bitumen obtained. from gas and other tars. The bitumen of
petroleum is soluble in the naphtha of petroleum, in bisulphide of carbon, and in
turpentine. The so-called vulcanized bitumen is insoluble in these solvents and soluble
only in the light or heavy oils with which it was combined before its separation. The
bitumen of petroleum and the vulcanized bitumen are unalterable by all atmospheric
agents. Acids are without action upon these bodies. Neither water, air nor humidity
attack them. They are very good insulators of electricity.

page_text: Applications Petroleum Bitumen. The properties and the nature of petroleum
bitumen are analogous to those of natural bitumien of Trinity, of Seyssel, of Val de
Travers etc. It results from this that petroleum bitumen serves the same applications
that the natural bitumen does. It may be cited:
Asphalte and Unalterable Bitumen. This application is one of the most important
above all in the conditions where asphalte is produced by this process. It is known
that natural asphaltes where made are mixtures of bitumen with calcareous and other
inert matters, generally little resisting. The natural bitumens even though purified
retain all these calcareous matters with which they were combined; also there does
not exist an asphalte capable of resisting chemical agents such as the acids or other
destructive products. Air and humidity combined attack rapidly the ordinary
asphaltes.
employ for the manufacture of the unalterable asphalte the burnt pyrites residue
in the manufacture of sulphuric acid. I mix in the ordinary conditions of the
manufacture of asphalte the petroleum bitumen and the burnt pyrites in the pro-
portions of one part of petroleum bitumen to two, three or sometimes four parts of
burnt pyrites. I obtain thus an asphalte of extreme hardness and apparently
unalterable to all the chemical agents. These qualities permit me to extend the
employment of the pyrites asphalte and of the petroleum bitumen to works for the
manufacture of chemical products or other industries where the ground is constantly
deteriorating by acid waters or other liquid destructive agents. Further theso
qualities make it more preferable in the applications where ordinary asphalte is
employed.
Asphaltic Cement: The petroleum bitumen is rendered malleable by a solvent of
petroleum naphtha and forms a paste that can be applied like cement, but asphaltic
cement has beyond the ordinary cement the advantage of being unalterable and of not
being cracked or bruised like ordinary cement.
Petroleum Bitumen Varnish. Petroleum bitumen is rendered completely liquid in
petroleum naphtha. In this state it forms an excellent waterproof coating or varnish
susceptible of numerous applications. The petroleum bitumen dissolved hot can also
be applied to cloth, cardboard, paper, etc. for awnings and other impermeable
products.
Petroleum Bitumen Coal. Mixed by dissolving hot with organic vegetable matters
such as sawdust, tan, fragments of linen, of cotton, of logwood, etc. it forms solid
combustibles, rich in gas and heating power. This product interests above all the
manufacturers and refiners who are at the places where the petroleum is extracted and
where the residues can be treated on the spot.
Distillation of Petroleumn Bitumen. If petroleum bitumen be submitted to
distillation it is surprising the series of hydrocarbon liquids which can be obtained
from it-naphtha, light and heavy oils in notable quantity up to 50%. The formation
of these hydrocarbons must be attributed to the purification treatment which indicates
that a bydrogenization of the material takes place. If the distillation be carried to
the end there remains in the retort a carbon of metallic appearance which after
If it
experiments that I have made ought to be largely employed for electrical use.
be found advantageous to distil the bitumen right on to the end.
Vulcanized Bitumen. The properties of this so called vulcanized bitumen are the
same as those of petroleum bitumen. Rendered malleable by its solution in the oils
which have been separated it can be made into unalterable asphaltes combining it with
burnt pyrites as I have already described in the case of petroleum bitumen. By the
same treatment is made an unalterable asphaltic cement and in complete solution it
forms a varnish of great solidity unalterable by chemical agents, replacing shellac and
susceptible in a great number of applications. It is an excellent varnish for the pre-
servation of receptacles for acid baths such as electric batteries, accumulators etc.
The vulcanized bitumen is an insulator of the first order and in electrical employment
it replaces advantageously the bitumen of Judea. Employed in the painting of
awnings and impermeable tissues the vulcanized bitumen under the form of varnish
gives excellent results.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, I declare that in the foregoing, I have given the fullest particulars of my
invention as perfected at the present time, but some parts are new since the date
of my provisional and these I intend to protect under another application by myself
or my patent agent, but that what I claim under the present application is:-
:-
.
1. The method of utilising acid residuums or tars resulting from the refining of
mineral oils, which consists in adding comminuted metal that will combine with the
acid of the tar, and washing out the resulting salts, substantially as described.
2. The method of obtaining metallic sulphates by the use of acid tar, substantially
as described.
3. The manufacture of the various products from acid residuums or tars resulting
from the refining of mineral oils above enumerated, substantially as described.
101
1000
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.