US99975A - Improvement in the manufacture of paraffine a - Google Patents

Description

UNrTEn STATES HERBERT W. o. 'TWEDDLE, or PITTSBURG, PENNSYLVANIA.

lMPROVEMENTlN THE MANUFACTURE OF PARAFFINE AllD PARAFFINE OILS.

Specification forming part of Letters Patent No. 99,97'5 dated February 15, 1870.

To all whom it may concern Be it known that I, HERBERT W. O. Twan- DLE, of the city of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in the Manufacture of Paratfine and .Paraffine Oils; and I do hereby declare the following to be a full, clear, and exact description thereof. i

My invention relates tothe distillationof petroleum or other hydrocarbon oils, which can be made to yield a considerable percentage of parat'fine; and consists in so carrying on the process of distillation that little or none of the paraffine will be decomposed, but most or all of it will pass over as vapor, and condense'in the distillate, from which it may then be separated by cold and pressure. Previous to the date of my invention, the efforts of oil-manufacturers were chiefly directed to securing from the crude oil the largest possible percentage of illuminating-oil, in which oil the presence of paraffine was objectionable.

Since the early history of oil distillation, a fire-heat of high temperature has been commonly applied to the outside of the still. When from forty-five to sixty per centum of the oil'was thus distilled over, the distillate marked 43 'or 44: Bauni hydrometer, and

was yellow in color and objectionablein odor.

In order to obviate these objections, various devices were adopted, such as high domes,-

goose-necks, &c., the immediate object being to decompose the heavier oils, which contained the parraffine, and prevent them from passing over into the condenser, as a result of which change the product was made lighter, both in gravity and color. By the use of such appliances, the vapors of the heavier oils, which contain the paraffine, are condensed in the dome or goose-neck and fall back into the still, Where they are decomposed by the high and destructive temperature of the fire, a part going over and being condensed into light illulninatin g oil, almost colorless, and a partforming carbides of hydrogen or other non-condensable gases and water, and another portion being precipitated or adhering to the sides or top of the still as solid carbonaceous matter.

The residuum left in the stills as the result of such process of distillation (of which residuum the carbonaceous matter last referred to formsa largepart) amounts to from three to ten per cent. of the oil distilled, and which sometimes existsin a tarry mass, or may be reduced to. a coke. If this residuum be distilled rapidly by fire-heat in large quantities, it will produce oils from 43 gravity down to 24 or 200 Baum, which oils,'when chilled and submitted to pressure, yield from eight and one-half to twelve pounds of pure paraffine per barrel of residuum, or from forty to sixty pounds per one hundred barrels of crudepetroleum. Such parafline so produced is at first ofa-dark olive green color, and the oil pressed out is 'heavy,' of ofl'ensive odor, and has a characteristic blue I orgreen color. Then a subsequent'seve're and expensive chemical treatment is required todecolorize both the paratfine and oil, and'to' somewhat deodorize the oil. p

4 At'ter being thus purified sdch oils are use as lubricants; but they are very deficient in body, and contain animal or vegetable oils, which compounds assume, to a great extent, the blue and green tint above referred to, which, in commerce, is objectionable, and pal-affine oils thus made do not command a ready sale for the above reasons. 9

My improved mode of producing paraffine and lubricating oil is, as a process, directly the reverse of that abovedescribed. Instead of decomposing the. paraffine, I so carry on the distillation as to prevent such decomposition as far as possible. In this process I distil with a comparatively low heat produced by free steam superheated or not at pleasure in a vacuum, or a partial vacuum, with or without a tire on the outside of the still, by which means I-am enabled to'produce paraffine in large quantity, and a superior quality of Inbricating-oil, both of which are of marketable quality, and in fit condition for use, requiring but little further chemical treatment.

To enable others skilled in the art to make use of my invention, I will proceed to describe the same.

The crude petroleum or other hydrocarbon,

having first been deprived of its lighter ingredients, such as gasoline, benzine, &c., by steam distillation or otherwise, is admitted intc a vacuum-still of such constructlon as to permi-t=the vapors of distillation to flow over freely ,,or, be drawn over, so that they, shall not condense before leaving the still.

By a perforated pipe, or in other suitable manner, I admit steam, common or superheated, into the body of thestill, keeping up at the sametime, by suitable appliances,- a partial or nearly complete vacuum. In connection with the steam-heat a'moderate fire V heat may be applied to the outside of the still in any of the Ways known to the art.

The process of distillation is carried on till'from thirty-eight to forty-eight per cent."of the crude material is driven off, which being condensed gives illuminating-oil as a product, at which point the distillation shows a gravity of about becomes richer and richer in parafiine as the distillation goes on, The condenser must H be kept warm while this is going on, or the parafline will solidify andclog the apparatus. After thel'distillation is finished, andparaffine ceases to come over, the residuum will be found to contain very little paraffine. The

distillation is then chilled and pressed. The

oil being expressed there remains paraffineof a good color, requiring very little further treatmentprevious to use. Com monl y remelting, rechilling, and repressing will sufiice to remove all deleterious or objectionable impurities, and produce a pure article of paraffine. In this way [obtain from eight tosixteen pounds of almost chemically pure paraffine per barrel of crude petroleum, the chief reasonot' this larger yield being that in this pro cess the paraffine vapors are formed by a comparatively low temperature, carried over freely, and condensed without being decomposed in y the still.

The oils which, in the process described, are expressed from the paraffine product are for lubricating purposes vastly superior to the lubricating oils produced by the tarry raiduum of the old process, or if made direct from petroleum by direct fire. Though of less gravity, averaging 30 to 35 Baum, they have a much better body. They have but a slight pungent odor, which is easily and al most wholly removed by a slight subsequent chemical treatment, and have hardly a trace of the blue or green tint which is a distinctive characteristic and an objectionable feature of lubricating-oils made by the ordinary process. The almost entire absence of the blue and yellow tint and offensive odor renders this oil, which I have introduced in commerce as neutral topaz oil, much more valuable than is a specific productof this mode or process of manufacture, and cannot be made 1n any other way. By the qualities specified it is readily distinguishable, by any one skilled in the art, from'all other lubricating oils heretofore known to the trade.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The process of producing paraffine, hereinbefore described, by an exhaustivedistillation of the heavy oil at a comparatively low temperature, by the use of steam in avac'uumstill, with or without a fire-heat, so as to drive over the parafline vapors undecomposed, substantially as described.

2. The production, by the process hereinbe fore described, of a lubricating-oil as a new article of manufacture, possessingthe distinctive and distinguishing features above set forth, viz., almost. entire freedom from the blue and green tints which characterize the paraffine oils of commerce.

3. The use, in the distillation of oil, of a vacuum or partial vacuum, in connection with steam, common or superheated, inside the still,

and an'auxiliary fire outside, substantially as described. a In testimony whereof I, the said HERBERT W. (J. TWEDDLE, have hereunto set my hand.

HERBERT W. O. TWEDDLE.

Witnesses:

W. BAKE ELL, A. S NIoHoLsoN.