MEANS OF TREATING AND PREPARING CERTAIN TAR OR NAPHTHA, AND APPLYING PRODUCTS
Year: 1853

page_text: LETTERS PATENT to Warren De la Rue, of Bunhill Row, in the
County of Middlesex, for the Invention of "MEANS OF TREATING
AND PREPARING CERTAIN TAR OR NAPHTHA, AND APPLYING PRODUCTS
Sealed the 6th October 1858, and dated the 25th July 1853.
PROVISIONAL SPECIFICATION left by the said Warren De
la Rue at the Office of the Commissioners of Patents, with his
Petition, on the 25th July 1853.
I, WARREN DE LA RUE, of Bunhill Row, in the County of Mid-
dlesex, do hereby declare the nature of the said Invention for
"MEANS OF TREATING AND PREPARING CERTAIN TAR OR NAPTHA, AND
APPLYING PRODUCTS THEREOF" to be as follows:-
The object of this Invention is the treatment of that description of
mineral substance known as Burmese naptha or Rangoon tar in order
to procure therefrom fluid and solid substances, and applying the same
as lubricators, as fuel for lighting purposes, and as solvents.
In order to effect this the mineral substance is submitted to a process
of distillation, which is effected, in the first instance, at as low a tem-
perature as possible, and with the aid of steam of 212° Fahrenheit
passed through the tar, which is kept heated to the temperature of the

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Warren De la Rue in the Great Seal Patent
Office, on the 18th January 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, ],
WARREN DE LA RUE, of Bunhill Row, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Hor
Letters Patent, bearing date the Twenty-fifth day of July, in the year
of our Lord One thousand eight hundred and fifty-three, in the seven-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Warren De la Rue, Her special
licence that I, the said Warren De la Ruc, my executors, admi-
nistrators, and assigns, or such others as I, the said Warren De la
Rue, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great

page_text: ,
Britain and Ireland, the Channel Islands, and Isle of Man, an inven-
on for MEANS OF TREATING AND PREPARING CERTAIN TAR OR NAPTHA AND
PPLYING PRODUCTS THEREOF," upon the condition (amongst others) that
the said Warren De la Rue, by an instrument in writing under my
and and scal, should particularly describe and ascertain the nature of
he said Invention, and in what manner the same was to be performed,
nd cause the same to be filed in the Great Seal Patent Office within
ix calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that T, the said Warren De la Rue, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement thereof (that is to say):
It is well known that the native petroleum napthas or tars are comi-
posed of various fluid and solid hydrocarbons, which boil at varying
temperatures, and can therefore be separated by processes of distilla-
tion, and the object of my Invention is to effect the separation econo-
mically, so as to render these products available for useful purposes,
such as varnish making, combustion and illumination, lubrication of
machinery or wheel work, and the solid product for the manufacture
of candles and other uses. I will now proceed to describe the means
I employ.
First, in order to prevent the loss as much as possible of the more
volatile constituents of the native petroleum, which in the case of
Rangoon tar I have found to occur when it is imported in wooden
barrels, I cause it, when collected at the natural sources, to be at once
placed in metallic casks or tanks having an aperture of convenient
size for the introduction of the liquid or pasty material, as the case may
be, and which aperture is to be closed hermetically as soon as possible;
as a precaution, I prefer to have a tin plate soldered over the opening.
In order to exclude the solid constituent as much as possible from
the first products of distillation, and also to prevent the natur
being altered by the long continuance of a high temperature, I effect
its partial distillation by blowing low pressure steam through it. To
5 effect this I introduce the petroleum into a metallic or other still which

page_text: is connected with a refrigerator cooled by a continuous current of cold
water. This still should be capable of holding twice the bulk of the ta
employed, but its form is not material (a plain cylinder answering as
well as any other), nor is it essential that it should be heated exter-
nally. To prevent loss of steam it is, however, desirable to surround the
still with a wood or other non-conducting casing. A. steam pipe con-
nected with a boiler producing steam of sufficient pressure to over-
come the weight of the column of petroleum through which it has to
pas enters the still through a steam-tight joint, and proceeds to within
an inch or two of the bottom of the still; here the open end of the
steam pipe either terminates or ends in a perforated coil pipe sup-
ported parallel with the bottom of the still. The still is provided with
several guage cocks for the purpose of ascertaining the height of the
fluid from time to time as it increases with the gradual condensation
of a part of the steam, and it should also be provided with a draw off'
cock or valve for the abstraction of this condensed water; this must
not be allowed to run to waste until the small quantity of petroleum,
which comes away with it frequently as a fine powder diffused through
it, has risen to the top. The first action of the steam is the heating
of the fluid, which gives off vapours of volatile hydrocarbons before
the tar has attained the temperature of 212° Fahrenheit, so that the
first distillate contains little or no water, but this gradually increases in
quantity, the steam serving as a vehicle for conveying the oily vapour
to the refrigerator until at last the oil comes over very slowly. It is.
better to stop this first part of the distillation so soon as the oils have.
diminished' to one sixth part of the distillate which runs into the
receiver. As the oils which distil over are lighter than water, the dis-
tillate. is allowed to flow into a separating vessel which allows of the
water running from the bottom, thence into a second and third, so as to
prevent loss of the oily products. These oils are collected fractionally, 3
or according to their respective volatility, the operator judging of this
by the speed at which the distillation takes place under like circum-
stances; the first portions are nearly colorless when the operation is
conducted carefully.
S
In order to purify the various distillates thus obtained they are 3

page_text: subjected two or more times to fractional distillation with the aid of
steam, collecting the distillate of each distillation in separate portions,
which are each distilled separately and the products collected frac-
tionally... The last distillates thus obtained should have their respective
boiling limits ascertained, and those of like boiling points may now be
mixed together.
The residue of the petroleum, after having been subjected to the
action of low pressure steam, is transferred into an iron still set in
brickwork, which should cover the still up to the point of juncture with
the refrigerator. The still is heated by means of an ordinary furnace,
and is furnished also with a steam pipe, which passes into it, and pro-
ceeds to within a few inches of the bottom. This steam pipe is in
connexion with a coil of pipes heated in a furnace, and communicating
with a steam boiler producing steam of sufficient pressure to overcome
that of the column of fluid in the still. The still and coil of pipes
towards the last part of the operation will have to be heated to between
600° and 700° Fahrenheit, but the distillation is conducted at as low
a temperature as possible, commencing at about 230° Fahrenheit, and
the heat of the coil of pipes and the still only gradually increased as
may be found necessary. By means of the supersaturated steam, that
is, steam heated by. means of the coil of pipes passing through the
furnace above the temperature it would acquire in contact with the
water in the boiler, the distillation of the naptha is effected at a much
lower température, and with less decomposition than could be done if
distilled without the aid of the supersaturated steam. The same result,
namely, subjecting the tar to the action of supersaturated steam, would
be obtained by either heating the boiler of the still only, or only the coil
of pipes, but the arrangement described is preferable. The vapors
which distil over are first made to pass into a refrigerator cooled by the
surrounding air, and in which the chief products condensed are oils,
and, lastly, into a refrigerator cooled by a current of cold water in which
some oil and all the water is condensed, which are separated by a suit-
able apparatus.
Most of the products of this second part of the operation, which are
collected fractionally, contain a solid crystallizable hydrocarbon, which
crystallises from them, particularly in cold weather, and may be sepa

page_text: rated by filtration. The more volatile products, however, contain little
or no solid hydrocarbon.
The various products obtained by the use of supersaturated steam
are first separately redistilled by means of steam at or about 212°,
which will carry over from the first portions especially a large portion
of oil, and then finally by means of supersaturated steam. By careful
rectification in this way the chief part of the solid hydrocarbon is retained
in the still, and comes over with the last products, and may be separated
by filtration. The solid substance thus obtained is first subjected to cold
pressure, and then to hot pressure, between layers of horse hair cloth, as
is practised with the fatty acids used in candle making, then heated to
212° Fahrenheit, with a fourth of its weight of oil of vitriol; it is now
washed with water, then with alkali, and again distilled and pressed.
Thus purified, it is white and diaphanous, and is fit for the manufacture
of candles, or as an unguent to replace tallow in lubricating.
The principal part of the oils are obtained colorless, except the latter
products, which have a pale yellow tint. As some of the oils obtained
have very high boiling points, they cannot on this account be burned
without a wick, but are very valuable for the fuel of such lamps as are
used for camphine, and their difficult ignitibility prevents the danger
in use which attends such inflammable compounds as turpentine or
camphine. From the high boiling point and consequent fixity of these
products they are extremely valuable as lubricators of machinery.
When the object is not to prevent the partial decomposition of the
solid hydrocarbon, instead of proceeding as above described, I sometimes,
after partial distillation of the naptha by means of low pressure steam,
place the residue in a shallow still heated by means of a naked fire,
which should play as much over the still as possible; this still must be
furnished with an 'alembic head, and protected by brickwork up to
the point where it cuters this head. This arrangement is necessary on
account of the facility with which the distillate condenses and runs back
again into the still, but the gutter channel within the alembic head
prevents this, the condensed fluid flowing into the neck and thence to
the refrigerator. To effect the entire distillation by this apparatus it
has at last to be raised to a temperature approaching a red heat, and
there is left a small residue of carbonaceous matter. In this mode of

page_text: procedure some of the solid hydrocarbon becomes converted into oily
fluids of very high boiling points. All the products obtained by distil-
lation with a naked fire I subsequently purify by distillation with the
aid of steam, as previously described.
By proceeding as before described a series of oils are obtained which
have boiling points progressively rising from a temperature below 200°
Fahrenheit to above 600° Fahrenheit, and even approaching a low red
heat. The complete separation of the constituent hydrocarbons or oils
is attended with much difficulty, as one volatilizes in the vapour of the
other, and for commercial purposes it is not necessary to effect a perfect
separation; I therefore confine myself usually to grouping the distillates
by the range of temperatures between which they boil. By distilling
with the aid of a thermometer, and stopping the distillation at certain
points, I sometimes effect a further purification, and by agitating the
more volatile oils with a fourth part of their weight of oil of vitriol, and
then washing, first with water, and afterwards with an alkaline solution,
I obtain on redistillation a still further purification.
What I claim is, the preparation of various solid and fluid hydro-
carbons from Burmese or other natural naptha, petroleum, or tars, in
the mamer described, and their application, when so prepared, to the
purposes of illumination, manufactures, and lubrication; also for the
employment of low pressure steam, and afterwards supersaturated
steam, to the distillation of similar native compounds.
In witness whereof, I, the said Warren De la Rue, have here-
unto set my hand and scal, this Fourteenth day of January, in
the year of our Lord One thousand eight hundred and fifty-
Witness,
ROBERT WARINGTON,
Apothecaries Hall,
London.
WARREN DE LA RUE. (L.S.)