US2039894A - Process of improving motor fuels - Google Patents

Description

J. c. GIENIESSE ET AL 2,039,894

PROCESS OF IMPROVING MOTOR FUELS May 5, 1936.

Fild March 9, 1928 zn l Patented May 5, 1936 UNITED STATES PATENT OFFICE I 2,039,894 rnooass F nurnovmo MOTOR FUELS Application March 9. 1928, Serial No. 60,342 17 Claims. (01. 196-50) The present invention relates to the improvement of fuels from the standpoint of anti-detonation, for general use in internal combustion motors, and especially in those having high compression; and more particularly our invention relates to a method for producing a fuel of increased anti-detonating qualities from a hydrocarbon oil with properties comparable with those of ordinary commercial gasoline.

l0 Heretofore various methods have been proposed for decreasing the detonation efiect, or what is ordinarily termed knocking, in the use of the ordinary motor fuels in internal combustion engines. Methods commonly known for in- 15 creasing the anti-detonation value of the com mon motor fuels include those in which various compounds, as, for instance, tetraethyl lead, aniline, benzol, or alcohol are added to the fuels, said fuels having been obtained as the result of one 20 of the recognized methods of distillation of crude petroleum. Likewise, such compounds as mentioned above have been added to the products obtained by cracking various cuts of crude petroleum, for the purpose of increasing their antidetonation value.- In other words, it has been heretofore recognized that fuels having a high anti-detonation value may be produced by the addition of certain substances to the commonly known motor fuels.

39 Inaccordance with our invention, petroleum distillates of approximately the distillation range of gasoline are subjected to a heat treatment at a relatively high temperature for a comparatively short length of time, for materially increasing 35 the anti-detonation value of the distillate. For

example, a straight run gasoline from a Mid- Continent crude oil may by such treatment have its anti-detonation characteristic increased an amount at least equivalent to that obtainable by the addition of 15 parts by volume of benzol to 85 parts of the gasoline. Among the oils whose properties are such as to adapt them for the treatment as hereinafter described is one which,

upon condensation immediately after heat treatment by ourmethod yields a condensate, at least 95% of wh ch will distilbelow 437 F., when subjected to the A. S. T. M. distillation test (D86-2'7) A further example of an oil or distillate with properties suitable for treatment by our process 59 is one of which, when subjected to the aforesaid distillation test, more than 50% or preferably at least 75% thereof will distil below 437 F.

The petroleum distillate to be treated in accordance with our invention is obtained from a 55 hydrocarbon oil by separating the particular diatillate from the components of the 011 not within the desired boiling range, by any of the usual distillation methods, or the petroleum distillate to I be treated may be obtained by cracking or breaking down a fraction of the crude oil resulting from a primary distillation to which the crude oil has been previously subjected.

The distillate or fraction of either of the characters just referred to is passed into a. heating system of any suitable construction which will cause the fraction or distillate to be brought quickly to a'high temperature and will maintain it at such high temperature for a period of time ranging from a few seconds to several minutes, for example for a period of from two seconds to one minute; the particular high temperature as well as the particular length of time depending upon the nature of the oil to be treated.

After the oil has been subjected to the intensive heat treatment it is passed into a condensing apparatus of any suitable type wherein it is liquefied. In particular instances it may be .desirable to subject the heat treated oil to a fractionating operation before it is liquefied, the

necessity of this step depending largely upon the particular properties of the oil being treated. In most cases it has been found that the change in the boiling range of the oil after it has been subjected to the heat treatment is not appreciable and therefore the step of fractionation is not required. The liquefied product obtained as condensate is then disposed of, as for instance by placing it in storage or by conducting it to a chemical treating plant.

The duration of heat treatment and the temperature at which it is carried out will vary with the oil to be treated and with the increase in anti-detonating value that is to be effected. The lowest temperature limit at which we find it practical to carry out the process herein disclosed is 850 F., and the maximum duration of the heat treatment is minutes. A temperature of from about 1000 F. to 1200" F. may be used.

Ari-example of the results attainable by our invention is the following. A straight run fraction from mixed base crude which by A. S. T. M.

assay distillation test (D86-2'7) showed. an over point of 144 F., 50% off at 288 F., and 97% off at 437 F., and a dry point of 460 F. has its antidetonation value increased to an extent equivalent to that obtainable by the addition of 26 parts by volume of benzol to '74 parts of the fraction,

by subjecting it to a temperature of 1076" F. for v a period of 5.6 seconds. This heat treatment has substantially no effect upon the boiling range. an

1 volume of the petroleum distillate and then sub- .iect the remaining 20%, which constitutes the higher boiling portion and of which more than 50% or preferably at least 75% will distil over below 437 F., to the heat treatment described, thereafter blending at least some of the treated portion with the portion distilled over, to produce a fuel of high anti-detonation value.

The distillate operated upon in accordance with our method, and which may be either a straight run or cracked distillate, or a mixture of them or a mixture of easing head gasoline with one or both of them, may be introduced into our heat. treating system either in liquid or vapor phase. Furthermore, our process may be practiced as a stage of a multi-stage system or process in which in an earlier stage the distillate to be operated upon in accordance with our method is produced. Our process maybe operated in combination or in continuity with a prior stage in which the distillate to be operated upon is produced. This distillate may be introduced into our treating system in the vapor phase, 1. e. without intermediate cooling or condensation.

For an understanding of our invention and for an illustration of one of the various forms our system may take reference is to be had to the accompanying drawing, in which:

Fig. 1 is a diagrammatic illustration of a system for heat treating a distillate in accordance with our invention.

Fig. .2 is a diagrammatic illustration of a system for producing or deriving the distillate to be operated upon in combination and continuity with which the system of Fig. 1 may be utilized.

Referring to Fig. 1, H is a heater of. any

suitable type, in which the distillate to be operated upon in accordance with our' invention is subjected to high temperature for a suitable period of time. In the example illustrated the heater comprises a series of tubes or pipes T disposed in the tube chamber A, whose lower end communicates with a flue a delivering waste gases or'products of combustion to a stack, not shown. Into the upper end of-the chamber A are discharged from the combustion chamber 13 the hot gases and products of combustion resulting from burning any suitable fuel, as, for exampie,.oil or gas delivered to the burner b. The oil or distillate to be treated is delivered either in liquid or vapor phase, under any suitable pressure, through the pipe to the inlet of the tube system T through which it rises, at suitable velocity to procure the desired duration of heat treatment, counter-current to the descending hot gases, and the vapors of the treated oil are discharged through the pipe d controlled by the valve 0, into the chamber 0 which, in the example illustrated, is a vertical fractionatingcolumn or tower in which are disposed the vertically spaced fractionating members D of any suitable type, such, for example, as bubbler plates, sieve plates, or equivalent. By suitably adjusting the valve 0 with respect to the pressure of the distillate entering through the pipe 0, the rate of flow through the heating none is controllable to eihct the aforesaid desirable duration of heat treatment. The distillate while in the tube system T is heated to a temperature of the desiredqrder hereinbefore indicated.

The vapors of the treated distillate pass upwardly through the column C, undergoing fractionation as well understood in the art, and pass oil from the top of the column through the pipe 1 controllable by valve vi to the condenser G cooled by any suitable medium, as water, introduced at i and discharging at k. The condensate, comprising the desired product, a motor fuel of increased anti-detonating characteristic, is delivered through the pipe 1,! controlled by the valve 125 to the flow box J where the stream is divided into any suitable proportions, part flowing through the pipe m to the separator S and the other portion flowing through the trapped pipe 2 into the top of the fractionating column C through which it descends, counter-current to the rising vapors, as reflux oil. In separator S gases and uncondensed components are drawn off through pipe controlled by valve 173, and

- the condensate or desired product is drawnoif through pipe .1: controlled by valve vi to storage, chemical treating plant or other desired destination.

At the bottom of the column C is provided a pipe 1, controlled by valve 120 through which is drawn of! the residual oil.

A pipe 1;, controlled by valve 01 connects with the pipe at and with the condenser (3 whereby;

all the vaporsffrom the heater tube system T or any desired portion thereof .may be passed directly to the condenser G and the condensate then passed to the pipe m, leading to the separating chamber 8, through the pipe m controlled by valve 02. This permits cutting out or omission of use of the. fractionatingcolumn C and flow ,box J, and. for this purpose the valves 0 and vi are closed, valve 111 opened, 0! opened, and v8 closed.

Delivering into the condenser G is a pipe 0, controlled by valve 08 for purposes hereinafter described; and with the pipe c communicate a pipe q controlled by valve 08 and a pipe 1 controlled by valve vll for purposes hereinafter described.

Referring to Fig. 2, there is represented generically a preceding stage in combination or in continuity with which the system or stage of 'Fig.

1 may be utilized. K is a fractionating column having vertically spaced fractionating plates D of any suitable character for fractionating vapors. introduced through the pipe e controlled by valve.

will, from any type of still or oil heating apparatus. The vapor introduced through the pipe e may be that resulting from a cracking operation, or from a simple fractionating or vaporizing still. The vapors ascend through the column K and pass of! through the pipe h controlled by 1 the valve oil to the partial condenser 1' in which aportion of the vapor is liquefied. The conden- .sate is returned to the top of the column K as reflux liquid through the pipe 1: controlled by the valve vii. The reflux liquid descends through the column counter-current to the rising vapors, effecting fractionation, and from the side of the column may be taken off several side streams or are passed through the pipe 1 controlled by the valve M3 to the pipe 0 of the system of Fig. 1 in whose tube system T they are raised to the desired temperature and for a period of the orders hereinbefore referred to. The vapors from the system of Fig. 2, constituting the distillate whose anti-detonation characteristic is to be enhanced, are accordingly operated upon in combination or in continuity therewith in the system of Fig. 1, yielding through the pipe at a distillate of improved anti-detonation property.

Or, through the pipe q there may be removed from a point adjacent the top of the column K a liquid fraction passed through the valve 129 to the pipe 0 and thence into the system of Fi 1 where that fraction receives the heat treatment characteristic of our invention. The heat treated vapors of this fraction pass into the condenser G of Fig. 1 into which are a so delivered through pipe 0 from the condenser F of Fig. 2 vapors of the lightest fraction from column K and these are mixed or blended with the vapors of the treated fraction drawn off through the pipe q and after treatment in system T delivered into the. condenser G. These blended vapors are condensed in condenser G and drawn off through the pipe :1: as a liquid condensate of improved anti-detonation characteristic. 0f the total distillate drawn off through the pipes h and q, that passing off through h may be of the order of and that through the pipe q of the order of 20%, the smaller proportion being heat treated in accordance with our invention in Fig. l and then again blended with the larger portion represented by the vapors passing off through the pipe 71.. For this operation the valve M3 is closed and the vapors from the partial condenser F are passed to the condenser G through the pipe 0 controlled by the valve 118.

The pressure upon the, oil while in the tubular system T of Fig. 1 may be anything suitable or desirable. It may be sub-atmospheric, substantially atmospheric, or super-atmospheric, for control of the velocity of the oil through the heatin zone for determining the desired duration of application of high temperature.

While our system and method as. described in connection with Fig. 1 is an important or essentia part'of our invention .it shall be understood that our invention comprehends also the use of the system and method of the character illustrated by Fig. 1 in combination or in continuity with a method or system of the character illus trated by Fig. 2.

It shall further be understood that our invention is not limited to the particular material, product, temperatures or time periods hereinbefore described both generally, and specificaly by way of example, but comprehends also other materials operated upon, products, temperatures,

time periods etc. falling within the scope of our appended claims which shall be construed as broadly as possible consistent with the state of the prior art.

By the term gasoline in the specification and appended claims. we mean a petroleum distillate having in general the boiling range of U. 8. motor gasoline defined in Technical Paper 323-13 of the Bureau of Mines. p. 3, and in particular any petroleum distillate having a dry point of 437 F. as defined in the aforesaid paper.

What we claim is:

1. A process for increasing the anti-detonation characteristic of gasoline, which comprises separating a portion thereof having a lower boiling range, and subjecting the remaining portion of higher boiling range to atemperature in excess of 850 F., whereby the anti-detonation characteristics of said portion are increased solely by thermal conversion.

2. A process of producing gasoline stock possessing anti-detonating characteristics, comprising, cracking a petroleum oil heavier than gaso-.

line under super-atmospheric pressure, releasing the pressure and primarily separating the naphtha stock produced, secondarily separating, by fractionation, the higher boiling portions of said naphtha stocii consisting mainly of hydrocarbons in the gasoline range from the lower boiling portion thereof passing the said separated higher boiling gasoline hydrocarbons through a cracking coil in a vapor phase at temperatures of 900 F. or above, separating the gasoline stock produced containing a high percentage of hydrocarbons possessing anti-detonating characteristics from the products of the last mentioned cracking reaction,'and commingling the said separated gasoline stock with the lower boiling hydrocarbons primarily separated from the said naphtha stock tov produce an anti-detonating motor fuel.

3. A process for increasing the anti-detonation characteristics of a gasoline which comprises subjecting the gasoline to fractionation to separate it into fractions of higher and lower boiling points, subjecting a higher boiling fraction to a temperature of the order of about 850 F. to 1000 F. whereby the anti-detonating characteristics of said fraction are increased solelyby thermal conversion and blending the gasoline fraction thus treated with the untreated porticz. of the gasoline.

4. A process for increasing the anti-detonation value of a motor fuel which comprises distilling off a portion of the motor fuel, subjecting the remaining portion, whereof more than 50% by volume will distil below 437 F. to heat treatment at a temperature in excess of 850 F. for a period of less than ten minutes, whereby the anti-detonation characteristics of said portion are increased solely by thermal conversion and blending at least some of the heat treated portion with the portion distilled off.

5. A process for increasing the anti-detonation characteristic of a gasoline which comprises separating a portion thereof having a lower boiling range, subjecting the remaining portion of higher boiling range to a temperature in excess of 850 F., whereby the anti-detonating characteristics of said portion are increased solely by thermal conversion and blending the untreated and heat treated portions.

6. A process for increasing the anti-detonation characteristic of a gasoline which comprises separating the larger portion thereof having low boiling range,.subjecting the lesser portion of higher boiling range to a temperature in excess of 850 F., whereby the anti-detonation characterislics of said portion are increased solely by thermal conversion and blending the untreated and heat treated portions.

'7. A method of producing motor fuel which comprises continuously fractionating vapors derived from petroleum to produce gasoline frac tions of different boiling ranges, and continuously passing that of said last named fractions having the higher boiling range through a heating zone for such period to raise it to a temperature of upwards of 850 F. to thereby materially increase the anti-detonation characteristic thereof solely by thermal conversion and thereafter blending the fraction so treated with the other of said motor fuel fractions.

8. A process for producing a motor fuel having high anti-detonating qualities which comprises separating gasoline into lighter and heavier fractions, subjecting at least one of said heavier fractions to heat treatment at a temperature in excess of 850 F. whereby the anti-detonation characteristics of said fraction are increased solely by thermal conversion and blending the fraction so treated with gasoline.

9. A process for producing a motor fuel having high anti-detonating qualities which comprises separating gasoline into lighter and heavier fractions, subjecting at least one of said heavier fractions to heat treatment at a temperature in excess of 850 F. for a period of less than ten min-= utes, whereby the anti-detonation characteristics of said fraction are increased solely by thermal conversion and blending the fraction so treated with gasoline.

' 10. A process for producing a motor fuel having high anti-detonating qualities which comprises separating gasoline into lighter and heavier fractions, subjecting at least one of said heavier fractions to heat treatment at a temperature of ing high anti-detonating qualities which comexcess of 850 F. for a period of less than ten minutes whereby the anti-detonation characteristics of said fraction are increased solely by thermal conversion, and blending the fraction so treated with a gasoline fraction to form gasoline.

12. A process for producing a motor fuel havprises separatinggasoline into lighter and heavier fractions, subjecting at least one of said heavier fractions to heat treatment at a temperature from 1000 F. to 1200 F. for a period of from tworseconds to one minute whereby the antidetonation characteristics of said fraction are increased solely by thermal conversion and blending the fraction so treated with a gasoline fraction to form gasoline.

13. The process of producing gasoline possessing superior anti-detonating characteristics as a motor fuel that comprises cracking a'petroleum oil heavier than gasoline, primarily separating the resultant naphtha stock from higher boiling materials, secondarily separating by fractionation the higher boiling portionsof 'said naphtha stock consisting mainly of hydrocarbons in the gasoline boiling range .from the lower boiling portion thereof, passing the said separated higher boiling gasoline hydrocarbons through a heating coil wherein the gasoline constituents are sub jected to a temperature of upwards of 850 F., separating the gasoline stock so produced from the other products of the last mentioned cracking reaction and commingling the said separated gasoline stock with the lower boiling hydrocara bons primarily separated from the said naphthastock to produce an anti-detonating gasoline.

14. The process of producing gasoline ins uperior anti-detonating characteristics as a motor fuel that comprises cracking as petroleum oil heavier than gasoline, primarily separating the resultant naphtha stock from higher boiling materials, secondarily separating "by fractionation the higher boiling portions of said naphtha stock consisting mainly of hydrocarbons in the gasoline boiling range from the lower boiling portion thereof, subjecting the said separated higher boiling gasoline hydrocarbons to heating at a temperature of upwards of 850 F. to eifect a transformation of hydrocarbon constituents into products of increased anti-detonating value and separating from the resultant products. of reaction a gasoline of high anti-detonating value.

15. The process of producing gasoline possessing superior anti-detonating characteristics as a motor fuel that comprises cracking a petroleum oil heavier than gasoline, primarily separating the resultant naphtha stock from higher boiling materials, secondarily separating by fractionation the higher boiling portions of said naphtha stock consisting mainly of hydrocarbons in the a gasoline boiling range from the lowerboling portion thereof, subjecting the said separated higher boiling gasoline hydrocarbons to heating at a temperature of upwards of 850 F. to effect a transformation of hydrocarbon constituents into products of increased anti-detonating value, separating a gasoline stock from the resultant products of reaction and commingling the said separated gasoline stock with a gasoline fractionto produce and anti-detonating a oline.

16. A process for increasing the anti-detonation characteristics of gasoline which'comprises subjecting the gasoline to fractionation to separate it into fractions of higher and lower boiling points, subjecting a higher boiling fraction to heatingat a temperature within the range of 850 F.-1200 'F. for a period of time upwards of two seconds and not exceeding ten minutes to thereby effect solely by thermal conversion a transformation of hydrocarbon constituents into products of increased anti-knock value and separating from the resultant products of reaction a gasoline having a high anti-knock value.

17. The process of producing gasoline possessing superior anti-detonating characteristics as a motor fuel that comprises heating crude petroleum to eifect vaporimtion of a naphtha stock and primarily separating the vaporized naphtha stock from the unvaporizedportion of the crude petroleum, secondarily separating by fractionation a higher boiling portion of said naphtha stock consisting mainly of hydrocarbons in the gasoline boiling range from a lower boiling portion'thereof, subjecting the said separated higher boiling gasoline hydrocarbons to heating at a temperature of upwards of 850 F. to effect a transformation solely by thermal conversion of CERTIFICATE OF CORRECTION.

Patent No. 2,039,894; May 5, 1936.

JOHN -C. GENIESSE, AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 4, first column, line 8, claim 8, after, "F." insert a comma; line 36, claim 11, forthe word "of" read in; line 46, claim 12, after "temperature" insert of; and second column, line 2'7, claim 15, for "boling" read boiling; line 56, same read an; and that the said Letters Patent should be read claim, for. "and" form to the record of with these corrections therein that the same may con the case in the Patent Office. I

Signed and sealed this 25th day of August, A. D. 1936 Leslie Frazer (Seal) Acting Commissioner ofPatents.

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