Improvements in Refining Oils.
Year: 1896

page_text: Date of Application, 21st Apr., 1896-Accepted, 30th May, 1898
COMPLETE SPECIFICATION.
Improvements in Refining Oils.
I, JAMES YATE JOHNSON, of 47 Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been
communicated to me from abroad by The Ohio Oil Improvement Company of
Cleveland, in the State of Ohio, United States of America) and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:
This invention has reference more particularly to the refining of a certain class
of mineral oils known as "Lima" or "Ohio" oils, which are heavily charged' with
sulphurous imparities of an obscure character, the composition of which has not
been determined. Oils of a similar character are. found in Canada and elsewhere
and are designated under the general name "sulphur-petroleums." and it is to be
understood that this invention is applicable generally to the treatment of oils
containing the sulphurous.compounds referred to, of which the Lima or Ohio oil
is an example. On account of these impurities, and of the great difficulty and
expense attending the removal of them, by hitherto known methods, the oils
referred to are of little commercial value. They are distinguished by a strong
and offensive sulphurous odour, and when burned give off disagreeable fumes and
produce a dark deposit on lamp chimnoys or other exposed surfaces.
My foreign correspondents have found that these oils can be refined in a simple,
expeditious and economical manner by a mode of treatment hereinafter set forth,
and which constitutes the present invention. This process consists in bringing the
crude distillate of an oil of the class referred to, into contact with an active element
or agent, such as lead, and an inactive element or agent, such as carbon. Lead
and carbon are the substances with. which. the best results have been obtained.
These materiale may be arranged in various ways;. but the simplest and best mode
of procedure with which my foreign correspondents are at present acquainted' is to
cause the oil to flow slowly between plates arranged. in close proximity but not
touching, thus obtaining effective exposure of the oil to the surfaces of the said
plates, and also rendering the operation continuous; since the dimension of the
plates, and the speed of flow of the oil. can he determined so as to secure the
desired period of exposure.
The invention may also be carried out. by agitating in a vessel, containing
pieces of lead and. carbon, the shape and size of. the pieces being subject to
variation..
It is not possible to state with certainty the nature of the action which occurs
in the oil when treated. in the manner stated above.. All. attempts heretofore"
made to determine. by analysis, the character of the impurities contained in oils
of the class referred to; have met.with no success. In order, therefore; that the
explanation may be made as clear as possible, and that those skilled in the art to
which this invention relates. may be able to understand the process fully and to
practice it with certainty; 1 will state the principal discernible effects' that occur
at various stages of the treatment..
After exposure; say from half an hour: to an hour, to the action of the plates,
the distillate (which originally is clear: and colourless) acquires a dark red' or
mahogany colour and becomes nearly opaque. When then treated with an acid
(such as sulphuric acid for. example) a liquid mass settlos to the bottom, out of
which a whitish powder. is precipitated. The clear product can be separated by

page_text: decantation. The said precipitate, which does not yield readily to analysis,
manifestly contains the source of the offensive odours characteristic of the
aforesaid oils, which distillation and the ordinary refining operations do not
remove.
In this treatment lead appears to be the principal or active agent in bringing
the oils to such a condition that the subsequent action of acid and alkali effectually
purifies and refines the oil. When lead alone is used the oil instead of turuing a
dark red, or mahogany, colour, as above stated, simply becomes cloudy, and that
the resulting product, while commercially useful, is not so good as when load and
carbon both are employed.
There is reason to believe that the result produced is not due to the corrosive
action of the lead, since by weighing the lead before and after an operation
resulting in the removal of four ounces of sulphurous impurities, no appreciable
loss of lead was detected. The change is therefore believed to be the result of
oxidation; but whatever be the nature of the change, or of the force producing
it, the fact remains that, by exposing the oil in thin strata to the influence of
surfaces, such as lead and carbon, a change in the oil is effected, of such
character that, upon addition of acid a precipitate is formed, as already described.
The carbon appears to be, and is herein termed, the inactive element, its presence,
or the presence of an equivalent, being necessary to bring about the action of the
active agent, or element, upon the impurities in the oil. The object of the
process is to convert the sulphur compounds in the oils into such a form that
the acid, afterwards applied, can act upon them. It is thereforo to be understood
that, in specifying lead and carbon as the active and inactive elemonts respectively
with which the hest results have been produced in practice, it is not intended to
limit the invention to those materials, to the exclusion of other equivalent bodies
whereby the same, or substantially the same, results may be obtained.
It is preferred in carrying out this invention, to discharge the oil from the
vessel in which it receives the described proliminary treatment, into a vessel
provided with a water bottom. The oil rising through the water deposits therein
Bome of the impurities that have been disengaged in the previous treatment.
some of the oils referred to a quantity of whitish substance is deposited in the
water of the receiving vessel.
With
Iron plates can be used in place of lead with results that are good, but not equal
to those obtained when lead is used.
In the accompanying drawings,
Figure 1 represents in sectional side elevation a simple form of apparatus that
may be used in practising this invention; aud
Figure 2 is a horizontal section of the tank or vessel.
A represents a tank having a lining a of lead, and B represents a carbon plate,
a little smaller than the interior of the tank A so as to leave thin spaces for the
flow of oil between the adjacent walls of lead and carbon, the carbon plate being
huug by supports 6 from the top of the tank and not allowed to touch the latter.
The oil after distillation is fed into the tank A through the pipe C, which, as
shewn, is connected to the bottom of the tank through which the oil rises and
finally overflows through the spout D. E represents the receiving vessel containing
water at e constituting a water-bottom. Preferably a pipe F is provided to conduct
the inflowing oil beneath the surface of the water, through which it rises lying ou
the top as indicated at f.
The oil should be fed slowly into the tauk A so as to iusure a sufficiently long
exposure to the influence of the lead and carbon plates. Of course, the flow may
be made faster when the size of the plates is increased. Observation will furnish
a guide to regulate the flow, since, if the oil issuing from the outlet does not show
a decided change of colour, the flow is too rapid. The colour of the oil, however,
issuing at the outlet is not the deep red or mahogany referred to, but a lighter
shade, which intensifies after the lapse of an hour or two.
It should further bo noted that the carbon plates should have clean surfaces, and

page_text: even when perfectly clean plates are used the first run of oil, sometimes for half an
hour, does not exhibit the characteristic change of colour. Longer contact there--
fore is desired in beginning an operation, but after the change of colour is observed
the operation may be carried on continuously.
The length of exposure to the action of the plates should also be governed by
the quantity of sulphur in the oil. In treating Lima distillate half an hour's
exposure bas ordinarily been found sufficient, but a longer exposure increases the-
amount of sulphur removed. The best indication by which to regulate the
length of exposure is that afforded by observation of the change of colour of the oil,.
as already stated.
In the subsequent treatment of the oil, the ordinary cominercial method is
followed. Sulphuric acid is used, of commercial strength, and it is removed by
washing with water and caustic soda, as usual.
The treatment of the oil is then continued according to the usual methods, which
require no explanation.
It will be observed that the described treatment is very simple, consumes but
little time, and involves no expense for chemicals.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The process of refining "sulphur-petroleums" by exposing the crude distillate
thereof to the influence of an active plate or element, such as lead, and an inactive
plate or element, such as carbon, and then treating with an acid, substantially as.
hereinbefore described.
2. In the process of refining oils containing sulphurous impurities, first distilling
the oil, then bringing the distillate into contact with metallic lead and carbon, and
then treating with an acid, substantially as hereinbefore described.
3. The process of refining oils such as are herein before specified consisting in.
distilling the oil, then causing it to flow slowly over carbon and lead surfaces and
subsequently treating with an acid, substantially as hereinbefore described.
4. The process of refining oils containing sulphorous impurities, consisting in.
exposing the crude distillate thereof in thin strata to the influence of carbon and
lead plates, until it changes colour, as hereinbefore explained, and then treating-
with an acid, substantially as herein before described.
5. The process of refining oils of the character hereinbefore specified by causing
the distillate thereof to flow over carbon and lead surfaces and discharging it into
a receiver containing a water bottoin, aubstantially as herein before described.
Dated this 21st day of April 1890.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.