US2276103A

US2276103A - Hydrocarbon conversion

Info

Publication number: US2276103A
Application number: US294618A
Authority: US
Inventors: Seguy Jean Delattre
Original assignee: Universal Oil Products Co
Current assignee: Universal Oil Products Co
Priority date: 1939-09-13
Filing date: 1939-09-13
Publication date: 1942-03-10
Anticipated expiration: 1959-03-10

Description

arch 10, 1942.

` J. D. sEGUY HYDROCARBON CONVERSION Filed Sept. l5, 1939 Patented Mar. i0, i942 i Application securiteA 13,1939, semi No. :sans

This invention relates-.to a process `foi-.prrniucing both motor and aviation-gasolina'. More.

I phase, concurrently therewith subjecting. nor

specifically, it is concerned with a process which involves a series of interdependent steps combined in a novel and advantageous manner so that the hydrocarbons are treated under loptivaluable products.

- mum'conditlons'for their vconversion intomore The invention broadly covers thermal 4 of hydrocarbon. oils in substantially thevapor phase to produce motor gasoline,lpyr o1ytic treatment of Cz and C: gaseous hydrocarbons, together with essentially only C4 parafllnick hydrocarbons, all ofwhich are formed in the process, to produce'pyrolytic polymer gasoline,vselectilve polymerization treatment of the C4 fraction formed in the process, and hydrogenation ofj the iso-octenes from said selective-polymerization treatment with the hydrogen contained in the light gas fraction formed in the process to produce iso-octane.

In the vapor phase cracking of normally liquid hydrocarbons relatively large quantities of normally gaseous hydrocarbons are produced, a high reaction chamber.

-mally gaseous hydrocarbons formed in the procl ess to pyrolytic treatment in a separate heating v coil and thereafter supplying the conversion products from said separate heating coil to said reaction chamber, cooling the v conversion '.prod.- I'

ucts from said reaction chamber by coinininglirlg therewith a relatively heavy hydrocarbon oil in- 4 troduced from an outside source, separating the mixture'of conversion products andcooling oil into-a non-vaporous liquid residue and vapors which include the vaporous conversion products', fractionating said vapors to form reflux conden'- sate and to separate fractionated vapors 4 in the range of gasoline, supplying at leasta i" portion of said reflui: condensate to said thermal,. cracking treatment, as aforesaid, cooling condensing said fractionated vapors and 'rec ering the resultingdistillate and gas, separating said distillate and said" g'as into` a methane-liyv drogen fraction, a Ca andCi fraction, a C4 fracv tion, and a gasoline fraction. recovering said gasoline fraction, said Ciand Ca fracpercentage of which are C4 hydrocarbons and 25 tion with the residual C43 fraction, separated' as particularly the olenic hydrocarbons of the C4 fraction. The C4 olenic hydrocarbons maybe polymerized in the presence of suitable catalysts hereinafter set forth, and 4subjecting the mixture tothe pyrolytic gas treatment, as previously set '.forth, subjecting said C4, fraction tov selective and under selected conditions to yield iso-octenes.

The iso-octenes upon hydrogenation are convert-"g ed to. iso-octane which is valuable as an aviation gasoline because bf its relatively high octane rating and low acid heat test. i

In the pyrolytic treatment of theCa and C: hydrocarbons, together with the residual C4 hydrocarbons from the catalytic polymerization polymerization' treatment to convert the oleilns to iso-octenes, fractionating the'conversion products from said selective polymerization ytreatment to separate aheavy polymer fraction, an iso-octene fraction, anda residual C4 fraction, commingling said residual-C4 fraction with said Cz and Ca fraction, as previously described, re-l y covering saidheavy Polymer fraction, subjecting treatment, a pyrolytic polymer is obtained which is valuable as a blending agent for ordinary moto dehydrogenation of the C4 paraillnic hydrocarbons subjected to treatment therein. The unsaturated C4 hydrocarbons formed in the pythe lighter normally gaseous hydrocarbons and said iso-octene'fraction to hydrogenation treatment in coinrningled state with said methanehydrogen fraction, and recovering the resultingv hydrocarbons comprisingy a relatively light hy- 'A drocarbon oil, such asfgas-oil and reflux con'- rolytic gas treatment after separation from the lighter gases and from the normally liquid hydrocarbons may be supplied to the polymerization treatment for conversion into iso-octenes.

One speciiic embodiment of the invention comprises subjecting combned feed comprising a relatively light hydrocarbon oil boiling above the range of gasoline and reilux condensate, lformed as hereinafter described, to thermal cracking treatment in a heating coil andcommunicating 55. version products, conslstingof hydrocarbons boildensate'formed` :in the process, 90% of which preferably boils lbelovv '100,` F., are 'subjected to cracking treatment infsubstantially the vapor phase to forml conversion products which con'-` tain both 'gasoline boiling range hydrocarbons and normally gaseous hydrocarbons in addition tothe heavy hydrocarbon components. The conl 4separated into selected fractions,

ing above gasoline, are returned to the cracking step, however, when heavy components are present, it is preferred that selected portions only.

such as those which have 90% boiling below 700 F. in an Engler distillation, be returned to the cracking system. The gases are preferably such as a methane-hydrogen fraction, a Cs-C: fraction, and a C4 fraction. The C i fraction is subjected to a catalytic polymerization treatment to convert the oleiins contained therein under selected conditions of temperature and pressure into isooctenes, which upon hydrogenation with hydrogen obtained from the methane-hydrogen fraction are converted to iso-octane. The Ca-C: fraction, together with the residual Cs fraction from the polymerization treatment, is subjected to pyrolytic treatment to form pyrolytic polymer gasoline and more C4 oleilnic gases.

Heavy oils, such as, for example, topped or reduced crude, which under vapor phase conditions have a strong tendency to form coke, may be utilized in the process, when desired, as a cooling oil and the lighter components thereof subjected to cracking treatment. This may be accomplished by commingling the heavy dil with the conversion products from the vapor phase cracking system and the pyrolytic gas treatment and thereafter separating and removing the non-vaporous portion in commingled state with the non-vaporous liquid residue formed in the cracking treatment and separating the vaporous portion thereof in commingled state with the vaporous conversion products.

The accompanying diagrammatic drawing illustrates in conventional side elevation one speciflc form of the apparatus in which the process of the invention may be conducted. It is not drawn to any exact or relative scale and furthermore it is not intended that the invention should be limited to the specific form of apparatus herein disclosed. I may, for example, employ other means for separating the hydrocarbon gases, all of which are included within the broad scope of the invention. The invention is limited only with respect to the material described and that disclosed in the prior art.

Referring now to the drawing, a hydrocarbon oil suitable for crackingin the vapor phase, such as, for example, a wide boiling range mixture of relatively low boiling range hydrocarbons, or any fraction thereof, such as gas-oil, is introduced through line i and valve 2 to pump 3, which discharges through line I and valve 5. The hydrocarbon oil in line 4 is commingled with reflux condensate, formed as hereinafter described, and the mixture introduced to heating coil I. The mixture introduced to heating coil 6 is substantially completely vaporized therein and raised to the desired cracking temperature which may range, for example, from 975to 1150 F. The heated vapors are maintained at a cracking temperature for a sumcient period of time to effect substantial conversion thereof, the heat of vaporization and cracking being supplied by furnace 1. The conversion products leaving heating coil I at a pressure ranging, for example, from 5 to 150 pounds or more per square inch are directed through line I and valve l into reaction chamber I0 where they are subjected to substantial further conversion by means of their contained heat. Reaction chamber il is operated at substantially the same or at a reduced pressure relative to that employed on the outlet of the heating coil and is also preferably insulated to reduce radiation losses therefrom, although' no insulation is shown in this drawing.

In another step of the process, concurrently with the vapor phase cracking treatment in heating coil I and reaction chamber Il, normally gaseous hydrocarbons. separated as' hereinafter described, are introduced t9 heating coil Il where they are subjected to pyrolytic treatment at temperatures ranging, for example. from 900 to 1400" F. and under a superatmospheric pressure of from 500 to 3000 pounds or more per square inch. The conversion products from heating coil il aredirected through line Il and valve Il into line 0 where they commingle with the conversion products from heating coil l prior to their introduction into reaction chamber Il. The conversion products from reaction chamber Il are directed through line Il and a valve Il, preferably cooled to arrest thecracking reaction by commingling therewith a hydrocarbon oil, and the mixture thereafter introduced to a vaporizing and separating chamber I1.

The cooling oil, which may comprise, for example, topped or reduced crude or any fraction thereof, or, when desired lighter hydrocarbon oils, is introduced through line il and valve It to Vpump 2l, which discharges through line 2i and valve 2l into line il where the cooling oil commingles with the conversion products, as previously described. f

Vaporizing and separating chamber I'I is preferably operated at substantially the same or at a reduced pressure relative to that maintained in reaction chamber Il and may range, for example, from 5 to 150 pounds per square inch. The mixture of cooling oil and conversion prodducts, due to its contained heat and the reduction in pressure in chamber I1, when the latter is employed, undergoes substantial vaporization to form a non-vaporous liquid residue which contains the heavy components of both the cooling oil and conversion products and hydrocarbon vapors which contain the lighter components of both the cooling oil and conversion products. The non-vaporous liquid residue separated vin chamber I1 is directed from the lower portion thereof through line 23 and valve 24 to cooling and storage or to any desired further treatment.

The hydrocarbon vapors separated in chamber I 1 are directed from the upper portion thereof through line 25 and valve Il into fractionator 21 which is preferably operated at substantially the same pressure or at a slightly reduced pressure relative to that employed in chamber i1. 'I'he hydrocarbon vapors introduced to fractionator 21 are fractionated therein to form reux condensate and to separate fractionated vapors boiling in the range of gasoline. When heavy hydrocarbons are present in the vapors in chamber I1, the reflux condensate formed in fractionator 21 may be divided into plurality of fractions and only selected light oils returned to the cracking treatment. For example, when the Engler distillation temperature of the reflux condensate i collected in the lower portion of fractionator 21 is substantially higher than 700 F., all of this reflux condensate may be recovered as a product of the process or supplied tot a separate mixed phase cracking system, if desired, in which case reflux condensate obtained as a side-stream from fractionator 21 may be supplied to vapor phase cracking treatment.

When all of the reilux condensate in fractionator 21 is supplied to the vapor phase cracking treatment, it maybe accomplished by directing said reiiux condensate from the lower portion of fractionator 21 through line Il.`valve Il. and line ll to pump 8|, which discharges through line 32 and valve It into line l, for'treatment as previously described. On the other hand, when the reflux condensate, removed'from the lower portion of fractionator 21, contains heavy -endswhich render the stock unsuitable for vapor phase cracking.- all of it may be recovered as a product of the process by `way of line 8l and valve 3i or supplied to any desired further treatment. In this case, a lighter remix condensate obtained as a side-stream from fraetionator 21may be supplied to the cracking treatment by way of line 36, line 3l, valve 31, pump 3|, line 82 and valve 33. When desired, a portion or all of the light reiiux condensate removed from fractionator 21 by way of line 3l may be recovered as a product of the process by withdrawing the same through valve 38. v

Fractionated vapors separated in fractionator 21 are directed through line 8l and valve Il to cooling and condensation in condenser Il. Distillate, together with undissolved and uncondensed gases, is directed from condenser 4| through line 42 and valve into receiver u where the distillate and undissolved and uncondensed gases are collected and separated. A portion of the distillate collected and separated in receiver Il may be returned to the upper portion of fractionator 21, by well known means not shown, as a reuxing-and cooling medium.

The remaining distillate in receiver I4 is directed from the lower portion thereof through line 45 and valve 46 to pump 41, which discharges through line Il and valve Il into absorber Il, while the undissolved and uncondensed gases collected in receiver Il are directed from the upper portion thereof through line |43 and valve I' to compressor I, which discharges through line |46 and valve H1 likewise into absorber Il. Absorber 5I is operated at a superatmospheric pressure on the order of 100 to 300 pounds or more per square inch and is preferably provided with a means for reboiling the liquid collected in the lower portion thereof. Reboiling, in the case here illustrated, may be accomplished by passing a suitable heating medium through closed coil 5I in indirect heat exchange relationship with the liquid within absorber Il. Gases and vapors rising in absorber il are contacted with a suitable absorption medium, introduced as` hereinafter described, to separate a methane-hydrogen fraction and to dissolve and condense the heavier components of the gases and vapors. The methane-,hydrogen fraction separated in absorber 5l is directed from the upper portion thereof through line 52 .and valve i3 into line III, for use as hereinafter described.

The liquid from absorber Il, comprising the distillate introduced thereto and an absorber oil containing dissolved and condensed gases-is directed through line il and valve l! to pump Il, which discharges through'line l1 and valve Il into depropanizer Il. Depropanizer II is oper-V ated at a superatmospheric pressure on the order of o to 400 pounds or more per square inch and is provided with a closed coil Il through which a suitable reboiling medium may be circulated. A normally gaseous hydrocarbon fraction containing substantially only Cz and C: hydrocarbons is separated from the heavier normally gaseous hydrocarbons and the liquid hydrocarbons in depropanizer It. The C: and C: fraction is directed from the upper portion of depropanizer 3 u aucun une tl and valve tja to pump' n. which dischargesthroughline and valve Il.

the Ca-Ca fraction commingled with a residual- C4 fraction, separated as hereinafter described.

, and the mixture subjected to pyrolytic treatment in heating coil Il. as previously i liquid, together with dissolved and condensed gases removed from the lower portion'ofdepropaniser it, is directed throughline and valve i1 to pump il, which discharges through line I and Valve 'IU into deblltltnlzer '|l. De-

rected through valve I4 into cooler l! where it ture is essentially gasoline boiling range hydrocarbons and C4 gaseous hydrocarbons it may be operated so that distillate collected in the lower portion thereof contains sufficient C4 hydrocarbons for the vapor pressure requirements ofthe distillate recovered in a subsequent separating stage of the process. The distillate collected in the lower portion Vof debutanizer 1|, either substantially free of C4 gaseous hydrocarbons or containing a suillcient amount for vapor pressure requirements, is directed through line 13 and valve 14 to pump 15, which discharges through line 16 and valve 11 into fractionator 1I.

Fractionator 18 is operated at a pressure ranging, for example, from substantially atmospheric to pounds or more per square inch and is provided with a suitable means for reboillng the lower portion thereof, such as closed coil '19. The material introduced to fractionator 1l is separated by fractionation into a light gasoline and a heavy gasoline, the former being removed as vapors and the latter as reflux condensate. Vapors separated in fractionator 1I are directed from the upper portion thereof through line ll and valve Il to cooling and condensation in condenser 82. Distillate, together with whatever undissolved and uncondensed gases that may be present, is directed from condenser I2 'through line Il and valve Il into receiver 85.l When undissolved and uncondensed gases are present. the same may be removed from the upper portion of receiver l! through line It and valve 81. light gasoline collected in the lower portion of receiver Il is removed therefrom by way d lne Il -Heavy gasoline collected in the lower portion yof fractionator 18 is directed through line Il and 'valve Il to pump 92. Pump l2 discharges through line I3 and a portion of the heavy gasoline is dl- .directed from the upper portion thereof through line III and valve N2 to compressor |03, which discharges through line Ill and valve il! into heating coil |03. The C; hydrocarbons in passing through heating coil |33 are raised to the desired polymerizing temperature by means of heat supplied from furnace |01 and are discharged therefrom through line |03 and valve |03 into reactor where they are subjected to contact with a -polymerizing catalyst selected to enect substantial polymerization of the isc and normal butenes introduced thereto into iso-octenes.

Sulfuric acid and phosphoric acid-containing catalysts are the preferred catalysts in the polymerization treatment, however, since sulfuric acid is more selective to the polymerization of iso-butenes and since temperatures and pressures when using phosphoric acid-containing catalysts may be selected to effect substantial conversion of both iso and normal butenes, the phosphoric acid-containing catalyst is therefore the preferred catalyst. The phosphoric acid-containing catalyst consists in general of a mixture of a relatively inert carrier such as kieselguhr impregnaied with the ortho or pyrophosphoric acid and is preferably precalcined before using. Polymerizing temperatures in the approximate range of 150 to 450 F. and superatmospheric pressures ranging, for example, from 800 to 1300 pounds per square inch may be employed when using the phosphoric acid-containing catalyst.

Reactor ||0 is preferably of the type which employs a plurality of relatively small diameter tubes containing the polymerizingcatalyst, the tubes being surrounded by a suitable cooling medium. The invention, however, is not limited to any specific type of reactor but may employ various other types, known to those skilled in the art, within its broad scope. Preferably and in order to obtain best results, a plurality of reactors is employed, connected in series with provisionsfor segregating one or more reactors from the group for the renewal of catalysts while the polymerizing treatment is being accomplished in the other or others, although only one is shown in the accompanying drawing.

The reaction products from reactor ||0 are directed through line and valve ||2 into fractioner ||3, operated at a superatmospheric pressure on the order of substantially atmospheric to 100 pounds or more per square inch, while the normally gaseous hydrocarbons are separated by fractionation from the normally liquid hydrocarbons and the latter further separated into an isooctene fraction and a heavy polymer fraction. When desired, a portion or all of the normally gaseous hydrocarbons separated in fractionator ||3 may be directed through line Ill and valve ||5 and into line 64, commingling therein with the Ce-Cz fraction, as previously described, or, when desired, a portion or all may be recovered by way of lines ||3 and H3 and valve |l1 and used for raising the vapor pressure of the distillate recovered from receiver. 85, and the iso-octane recovered as hereinafter described Preferably, however, only the amount required for raising the vapor/pressure of the distillates is removed from fractionator I|3 and the residual portion subjected to pyrolytic treatment, as previously described. Heavy polymers, comprising principally trimers and heavier of the butenes, are removed from the lower portion of fractionator ||3 by way of line ||3 and valve H3, cooled and recovered as a product of the process or, when desired, this material may be supplied to the thermal cracking treatment for conversion to lower boiling hydrocarbons.

. 'I'he iso-octenes separated as an intermediate changer ll by way of line |23 and valve |21 and.v withdrawn therefrom by way of line |28 and valve |29. The iso-octene fraction at the desired temperature is directed from heat exchanger |25 through line |30 and valve |3|, commingled with the methane-hydrogen fraction, as previously described, and the mixture supplied to reactor i |32. Reactor |32' may be of substantially the same design as reactor H0, however, as was previously mentioned, various other types of reactors may be employed.

Hydrogenation in reactor 32 may be accomplished in the presence of a catalyst whichin the preferred embodiment of the invention consists of nickel on relatively porous particles of a relatively inert siliceous carrier, such as kieselguhr. The catalysts may be produced by precipitating nickel carbonate on kieselguhr, pressing into pills, drying and reducing directly with hydrogen at a temperature of '150 F. However, other hydrogenating catalysts, well known in the art, such as, for example, the oxides of chromium, molybdenum, and tungsten may be employed, when desired. Temperatures ranging, for example, from 250 to 450 F. and superatmospheric pressures in the approximate range of 15 to 200 pounds or more per square inch may be employed when using a nickel catalyst.

The hydrogenated products, together with the unused excess hydrogen, are directed from reactor |32 through line |33 and valve |34 to cooling and condensation in condenser |33. Distillate comprising substantially iso-octane, together with the undissolved and uncondensed `gases from condenser |33, ls directed through line |33 and valve |31 into receiver |33 for collection and separation. Unused hydrogen, together with any normally gaseous hydrocarbons collected and separated in receiver |33, is removed from the upper portion thereof by way of line |33 and valve |33 and returned to reactor |32, by well known means not shown, for reuse or recovered as a product of the process. The iso-octane co1- lected in the lower portion of receiver |33 is re' moved therefrom by way of line MI and valve |32 and recovered as a product of the process.

An example of one specific operation as it may be accomplished in an apparatus such as illustrated and above described is approximately as follows:

Combined feed, comprising a 33 A. P. I. gravity Mid-Continent gas-oil and reflux condensate, formed as hereinafter described, was subjected to vapor phase cracking treatment in a heating coil at a temperature of 1025 F. and at an outlet pressure of approximately 75 pounds per square inch. Concurrently therewith, a gas fraction, comprising essentially Cz, Cr, and substantially paramnic C4 hydrocarbons formed in the process, was subjected to pyrolytic treatment in a separate heating coil at a temperature of i075 F. and at a pressure of approximately 800 pounds per square inch. The conversion products from both heating coils were commingled and the mixture'subjected to prolonged conversion treatment in a reaction chamber operated at a superatmospheric pressure substantially. the same as that Gmilyed on the outlet of the vapor phase crack- -v The conversion products from the reaction chamber were cooled to arrest the cracking r'eaction by commingling therewith a 25A. P. I. 5

gravity Mid-Continent reduced crude oil and the mixture supplied to a vaporizing and separating zone operated at a superatmospheric pressure of approximately 50 pounds per square inch. Nonvaporous liquid residue was separated from the vaporous components and the mixture supplied to the vaporizing and separating zone and the former recovered as a product of the process. The vaporous components were subjected to fractionation at a superatmospheric pressure substantially the same as that maintained in fthe vaporizing and separating zone to form light and A heavy reux condensates and to separate fractionated vapors boiling in the range of gasoline.

The heavy reiiux condensate was subjected to g5 mixed phase thermal cracking treatment in a separate system. The light combined feed was commingled with the gas-oil charging stock and subjected to vapor phase cracking treatment, as previously described. Fractionated vapors were separated into a noncondensible gas fraction comprising essentially hydrogen and methane, a Cz-Ca fraction. a C4 fraction, and a gasoline fraction, the latter being recovered as a product of the process. The

Cz-Ca fraction was subjected to pyrolytic treatment, as previously described.

The C4 fraction was subjected to selectivepolymerization treatment in the presence of a phosphoric acid-containing catalyst at a temperature a5 of 250 F. and at a superatmospheric pressure of 1000 pounds per square inch to form iso-octenes and isoand normal butenes. Products from the polymerization treatment were fractionated at a superatmospheric pressure of approximately 5 s0 fraction was subjected to hydrogenation treat- 5o ment in the presence of a nickel catalyst at a temperature of 275 F. and at a superatmospheric pressure of approximately 25'pounds per square inch, the hydrogen contained in the hydrogenmethane fraction being used in the hydrogenation treatment. The products from the hydrogenation treatment were subjected to cooling and condensation, and the resulting gas and liquid collected and separated.

'I'his operation yielded approximately 46.5% of 60 'i5 octane gasoline, 3.1% of iso-octane having an octane rating of approximately 96, 18.0% of heavy reflux condensate, and 21.3% of nonvaporous liquid residue.

'Ihe yields above stated correspond to volume 65 1. A process for the production of motor and v aviation gasolines, which comprises subjecting a' hydrocarbon oil to thermal cracking treatment in substantially thevapor phase toeffect sub stantial conversion thereof into gas, gasoline,

and intermediate conversion products, vreturning l'if' .the intermediate conversionlproducts to thermal cracking treatment, recovering saidgasoline. separating said gas into a hydrogen-methane fraction, a two and three carbon atom` fraction. and a four carbon yatom fractionr subjecting said two and three carbon atom fraction, to-

gether with residual four carbon atom hydrocarbons separated in a subsequent stage to pyrolyti'c treatment and combining the pyrolytic polymers' and gases produced therein with the products of of said cracking treatment, subjectingsaid four carbon atom fraction to polymerization treatment to effect substantial polymerization ofthe `olefins to iso-octenes. commingling the residual four carbon atom fraction from said polymerization treatment with said two and three carbon atom fraction, as aforesaid, subjecting the isooctenes from said. polymerization treatment to` hydrogenation treatment with hydrogen of said hydrogen-methane fraction and recovering therefrom. iso-octane. v

'2. A process for the production of motor and aviation gasolines, which comprises subjecting combined feed comprising charging oil and renux condensate, formed as hereinafter set forth, to thermal cracking treatment in substantially the vapor phase, concurrently therewith subjecting two and three carbon atom and four carbon atom hydrocarbons formed inthe process to pyrolytic treatment, commingling the conversion products from both treatments and separating non-vaporous liquid residue from the vaporous components of the mixture of conversion products, recovering said non-vaporous liquid residue.' fractionating said vaporous Vcomponents to form reflux lcondensate and to separate fractionated vapors, commingiing at least a portion of said reux condensate with said charging' oil to form combined feed, as aforesaid, separating said fractionated vapors into a non-condensible gas fraction comprising essentially hydrogen and methane, a two and three .carbon atom fraction, a four carbon atom fraction, and a gasoline fraction, recovering the latter, supplyas ing said two and three carbon atom fraction in commingled state with the residual four carb'on atom fraction, separated as hereinafter set forth to said pyrolytic treatment, subjecting said four carbon atom fraction to polymerization treatment to effect polymerization of the oleiins contained therein to iso-octenes, separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a heavy polymer fraction, recovering the latter, commingling said residual four carbon atom -fraction with the two and three carbon atom fraction, as aforesaid, subjecting said iso-octene fraction to hydrogenation treatment in commingled state with said non-condensible gas fraction and recovering therefrom iso-octane.

3. The process claimed in claim 2 wherein the heavier portion of the reflux condensate formed in fractionating the vaporous components is recovered and only the light reflux condensate is subjected to the thermal cracking treatment.

4. A process for the production of motor and aviation gasolines, which comprises subjecting combined feed comprising charging oil and reflux condensate, formed as hereinafter set forth. to thermal cracking treatment in substantially the vapor phase, concurrently therewith subjecting two carbon atom, three carbon atom, and four carbon atom hydrocarbons formed in the process to pyrolytic treatment, comminglingthe conversion products from said thermal cracking and said pyroiytic treatments and subjecting the mixture to prolonged conversion treatment in a reaction chamber, cooling the conversion productsfrom said reaction chamber by commingling therewitha suitable cooling oil, separating nonvaporous liquid residue fromthe vaporous components of the-mixture of conversion products and cooling oil, recovering said non-vaporous liquid residue, fractionating said vaporous components to form redux condensate and to separate fractionated vapors, commingling at least a portion of said redux'condensate with said charging oil to form combined feed, as aforesaid, separating said fractionated vapors into a noncondensible gas fraction comprising essentially hydrogen and methane, a two and three carbon atom fractionI a four carbon atom fraction, and a gasoline fraction, recovering thelatter, supplying said-two and three carbon atom fraction in commingled state with the residual four carbon atom fraction, separated as hereinafter set forth, to said pyrolytic treatment, subjecting said four carbon atom fraction to polymerization treatment to eii'ect polymerization oi' the oledns contained therein to iso-octenes. separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a heavy polymer fraction, recovering the latter, commingling said residual four carbon atom fraction with the two and three carbon atom fraction, as aforesaid, subjecting said iso-octene fraction to hwdrosenation treatment in commingled state with said non-condensible gas fraction and recovering therefrom iso-octane.

5. A process for the production of motor. and aviation gasolinas, which comprises subjecting combined feed comprising charging oil and redux condensate, formed as hereinafter s'et forth.

to thermal cracking treatment in substantially the vapor phase, concurrently therewith subjecting two carbon atom, three carbon atom and four carbon atom hydrocarbons formed in the process to pyrolytic treatment, commingling the conversion products from said thermal cracking and said pyrolytic treatments and subjecting the mixture to prolonged conversion treatment in a reaction chamber, cooling the conversion products from said reaction chamber by commingling therewith a suitable cooling oil, separating nonvaporous liquid residue from the vaporous components of the mixture of conversion products and cooling oil, recovering said non-vaporous liquid residue, fractionating said vaporous components to form redux condensate and to Beparate fractionated vapors, commingling atleast a portion of said redux condensate with said charsins oil to form combined feed, as aforesaid, cooling and condensing said fractionated vapors to form distillate and gas and subjecting the resulting distillate and gas to absorption and successive fractionations to separate a non-condensible gas fraction, consisting essentially of hydrogen and methane, a two and three carbon atom fraction, a four carbon atom fraction, and a gasoline fraction, recovering the latter, supplying said two and three carbon atom fraction in commingled state with the residual four carbon atom fraction, separated as hereinafter set forth, to said pyrolytic treatment, subjecting said four carbon atom fraction to polymerization treatment to edect polymerization of the oledns contained therein to iso-octenes. separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a commingling said residual four carbon atom fraction with the two and three carbon atom fraction, asA aforesaid, subjecting said iso-octene fraction to hydrogenation treatment in commingled state with said non-condensible gas fraction and recovering therefrom iso-octane.`

8. A process for the production of motor and aviation gasolines, which comprises subjecting combined feed comprising charging oil andl redux condensate, formed as hereinafter set forth, to thermal cracking treatment in substantially the vapor phase, concurrently therewith subjecting two, three, and four carbon atom hydrocarbons formed in the processto pyrolytlc treatment, commingling the conversion products from said thermal cracking and said pyrolytic treatments and subjecting the mixture to prolonged conversion treatment in a reaction chamber, cooling the conversion products from said reaction chamber by therewith a suitable cooling l oil, separating non-vaporous liquid residue from the vaporous components of the mixture of conversion products and cooling oil, recovering said non-vaporous liquid residue, fractionating said vaporous components to' form redux condensate and to separate fractionated vapors, commingling at least a portion of said redux condensate with said charging oil'to form combined feed, as aforesaid.- cooling and condensing said fractionated vapors to form distillate and gas and subjecting the resulting distillate and gas to absorption and successive fractionations to separate a non-condensible gas fraction consisting essentially of hydrogen and methane, a twoand three carbon atom fraction, a four carbon atom fraction, and a gasoline fraction, recovering the latter, supplying -said two and three carbon atom fraction in ment in the presence of a phosphoric acid-conheavy Polymer fraction, recovering the latter,

taining catalyst to eifect polymerization of the olefins contained therein to iso-octenes, separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a heavy polymer fraction, recovering the latter, commingling said four carbon atom fraction with the two and three carbon atom fraction, as aforesaid, subjecting said iso-octene fraction to hydrogenation treatment in commingled state with said non-condensible gas fraction in the presence of a nickel-containing catalyst and recovering therefrom iso-octane.

'1. A process for the production of motor and aviation gasolinas, which comprises subjecting combined feed comprising charging oil and redux condensate, formed as hereinafter set forth, to thermal cracking treatment in substantially the vapor phase, concurrently therewith subjecting two, three, and four carbon atom hydrocarbons formed in the process to pyrolytic treatment, commingling the conversion products from said thermal cracking and said pyrolytic treatments and subjecting the mixture to .prolonged converleast a portion of said redux condensate with said charging oil to form combined feed, as aforesaid, cooling and condensing said fractionated vapors to form distillate and gas and subjecting the resulting distillate and gas to absorption and successive fractionation to separate a non-condensible gas fraction consisting essentially of hydrogen and methane, a two and three carbon atom fraction, a four carbon atom fraction, and a gasoline fraction, recovering the latter, supplying said two and three carbon atom fraction in commingled state with the residual four carbon atom fraction, separated as hereinafter set forth, to said pyrolytic treatment, subjecting said four carbon atom fraction to polymerization treatment in the presence of a phosphoric acid-containing catalyst at a temperature of from 150 to 450 F. and at a superatmospheric pressure of from 800 to 1300 pounds per square inch to effect polymerization of the olefins contained therein to iso-octenes, separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a heavy polymer fraction, recovering the latter, commingling said residual four carbon atom fraction with the two .and three carbon atom fraction, as aforesaid, subjecting said iso-octene fraction to hydrogenation .treatment in commingled state with said non-condensible gas fraction in the presence of a nickelcontaining catalyst at a temperature of from 250 to 450 F. and at a superatmospheric pressure of from 15 to 200 pounds per square inch and recovering therefrom iso-octane.

8. A process for the production of motor and aviation gasolines, which comprises subjecting combined feed comprising charging oil and reflux condensate, formed as hereinafter set forth, to thermal cracking treatment in substantially the vapor phase at a temperature of from 975 to 1150 F. and at a superatmospheric pressure of from to 150 pounds per square inch, concurrently therewith subjecting two, three and four t carbon atom hydrocarbons formed in the process to pyrolytic treatment at a temperature of from 900 to 1400 F. and at a superatmospheric pressure of from 500 to 3000 pounds per square inch, commingling the conversion products from said thermal cracking and said pyrolytic treatments and subjecting the mixture to prolonged conversion treatment in a reaction chamber, cooling the conversion products from said reaction chamber by commingling therewith a suitable cooling oil,

separating non-vaporous liquid residue from the vaporous components of the mixture of conversion products and cooling oil, recovering said non-vaporous liquid residue, fractionating said vaporous components to form reux condensate and to separate fractionated vapors, commingling at least a portion of said reflux condensate with said charging oil to form combined feed, as aforesaid, cooling and condensing said fractionated vapors to form distillate and gas and subjecting the resulting distillate and gas to absorption and successive fractionation to separate a non-condensible gas fraction consisting essentially of hydrogen and methane, a two and three carbon atom fraction, a four carbon atom fraction, and a gasoline fraction, recovering the latter, supplying said two and three carbon atom fraction in commingled state with the residual four carbon atom fraction, separated as hereinafter set forth, to said pyrolytic treatment, subjecting said four carbon atom fraction to polymerization treatment in the presence of a phosphoric acid-containing catalyst at a temperature of from to 450 F. and at a superatmospheric pressure of from 800 to 1300 pounds per square inch to effect-polymerization of the olefins contained therein to iso-octenes, separating the polymerization products into a residual four carbon atom fraction, an iso-octene fraction, and a heavy polymer fraction, recovering the latter, commingling said residual four carbon atom fraction with the two and three carbon atom fraction, as aforesaid, subjecting said isooctene fraction to hydrogenation treatment in commingled state with said non-condensible gas fraction in the presence of a nickel-containing 'catalyst at a temperature of from 250 to 450 F. and at a superatmospheric pressure of from 15 to 200 pounds per square inch and recovering therefrom iso-octane.

9. The process claimed in claim 8 wherein cooling oil comprises essentially a high-boiling hydrocarbon oil.

10. The process claimed in claim 8 wherein the heavy portion of the reflux condensate formed in fractionating the vaporous components is recovered and only the light reux condensate subjected to' thermal .cracking treat-l ment.

JEAN pmi-ran sEGUY.