US2375675A - Process of treating hydrocarbon materials - Google Patents

Description

May 8, 1945. M. P. MATUSZAK. 2,375,675.

PROCESS OF TREATING HYDROCARBON MATERIALS Filed March 10, 1942 ISOBUTANE ISOBUTANE moEmEmw ISOBUTAN E TREATER KOPUEZOU 3 RESIDUE PURIFIED MATERIAL 'HYDROCARBON MATERIAL INVENTOR MARYAN MATUSZAK M ATTZM?7M Patented May 8, 1945.

- rnocEssoF TREATING HYDROCARBON MATERIALS Maryan P. Matuszak, Bartlesville. kla., assignor to Phillips Petroleum Company, a corporation of Delaware Application March'10, 1942, Serial No. 434,120 (c1. 196-31) 4 Claims.

. This invention relates to the treatment of hydrocarbon materials, and more particularly to hydrofluoric acid treatment/of hydrocarbon materi-als containing gums, resins, sulfur compounds, orother undesirable constituents. under such conditions as to remove substantially-all of these constituents. It relates still more particularly to the refining of hydrocarbon materials with used or spent hydrofluoric acid-containing catalyst obtained from the alkylation of alkylat-- able hydrocarbons. This application is a continuation in-part of my copending application,

Serial No. 395,2 80,'fl1ed May 26, 1941.

Heretofore, hydrocarbon materials containing unsaturated hydrocarbons, sulfur compounds, gum-forming compounds, and/or other undesirable constituents have been generally treated with stituents. For e xample, ithas been a common practice to refine hydrocarbonoils by sulfuric Further objects and advantages ofthis invention will be-apparent from the following description, the accompanying drawing, and the appended claims.

During the treatment in accordance with the present invention, the hydrocarbon material and the hydrofluoric acid are preferably in the liquid phase, although application of the invention is a not to be limited to treating only in liquid phase; in some instances, as in the treatment of a fourcarbon hydrocarbon fraction or similar low-boiling fraction, the hydrocarbon material may be at least partly in the vapor phase. Usually, how- I ever, the hydrocarbon material to be treated according to the invention will be one'or more hydrocarbon oils ordinarily susceptible to refining by acid treatment, such as petroleum oils,- distilsuli'uric acid '-to remove such undesirable conacid treatment. In many cases, this treatment is only partly successful, apparently because of the oxidizing action of the acid, which may be especially pronounced when highly concentrated sulfuric acid is used. This oxidizing action isof such a nature that substances are produced in.

the main body of the hydrocarbon material which bring .about'an unstable condition in the material with respect to color and odor.

In accordance with this invention, hydrocarbon materialscan be advantageously freed of substantiallyall unsaturated hydrocarbons, resins, sulfur compounds, colorand/or gum-forming compounds, and the like by treating these hydrocarbon materials with substantial amounts of hydrofluoric acid, which is free from the 'oxi'- dizing action of sulfuric acid, and which has become spent and comparatively ineffective for further use as a catalyst in the alkylation of alkylatable hydrocarbons with olefin hydrocarbons.

One object of this invention is to remove undesirable constituents of the nature of sulfur compounds, colorand gum-forming; compounds, andthe like from hydrocarbon materials.

Another object is to provide an improved process for removing such constituents.

Another object'of this invention is the gainful use of hydrofluoric acid which has become spent as an alkylation catalyst, before'it is subjected to treatment restoring it for reuseas an alkylation catalyst.

Another object is to combine advantageously an acid treatment of hydrocarbon materials with taining catalyst.

lates, lubricating oil, akerosine, naphtha, gasoline,-

hydrocarbons, preferably isoparaflins, with alkylating agents, preferably oleflns, without any intermediatetreatrnent. However, an intermediate treatment with an alkylatable hydrocarbon, preferably the same alkylatable hydrocarbon as 1 that being alkylated in the alkylation step, is ad- .vantageous, as thereby the spent hydrofluoric acid loses part of its content of acid-soluble organic compounds, and the alkylatable hydrocarbon becomes saturated with hydrofluoric acid. Such intermediate treatment is further described hereinafter.

The amount of spent hydrofluoric. acid should be sufllcientto form a distinct and appreciable liquid phase containing the major proportion of the acid under the conditionsof the treatment; it is preferably several times this amount. The exact amount that is necessary to effect a given extent of refining will vary with the nature of the hydrocarbon material being treated, especially with the content of constituents that are to be removed. Generally, it should not be less than that required to produce a substantially completely saturated hydrocarbon product. An amount of hydrofluoric acid equal to or perhaps several timesthe volume of the hydrocarbon material to be treated may be set as about the maximum that mayneed to be used. However, an amount between 10 and 50 per cent by volume of the hydrocarbon material usually will be found phase.

.rmally liquid hydrocarbon phase without the loss of this material that would occurif the removal invention. Furthermore, when acid-soluble compounds are the predominant constituents in a mixture containing also non-hydrocarbon constituents substantially inert to and insoluble in hydrofluoric acid under the prevailing conditions, the invention will find particular application for removing substantially all of the acid-soluble compounds therefrom.

The mutual solubility of liquid or liquefied hydrocarbons and of liquid hydrofluoric acid increases appreciably with increase in temperature, and this effect of temperature should be taken into consideration in establishing the treating conditions in any particular case. Usually, how-' ever, the treatment .may be satisfactorily conducted at temperaturesiin the range from about l to about 300 F., although in most cases a range between about 0 and about 150 F. is preferable. The pressure should be sufficient to insure proper flow through the apparatus; when 1 liquid-phase operation is desired, it should be sufllcient to insure the liquid phase at the tem; perature of operation.

' In th treatment of normally liquid hydrocarbon materials, such as motorfuels, kerosines, fuel oils, lubricating oils, and the like, a relatively low-boilingliquef-led paramn, such as propane or .a butane, preferably normal butane, or a mixture of relatively low-boiling liquefied parafllns, "can be added to the normally liquid h'ydrocar-. bon material before, during, or after contacting f with the hydrofluoric acid. This low-boiling hydrocarbon material aids in subsequent removal of residual hydrogen fluoride dissolved in the hydrocarbon phase after physical separation of the hydrocarbon phase from the hydrofluoric acid phase. Thus in a preferred manner of opcratin a normally liquid hydrocarbon material is treated with spent alkylation hydrofluoric acid; an acid phase is separated from a hydrocarbon phase containing the normally liquid hydrocarbons and dissolved hydrofluoric acid; and then a low-boiling liquefied paraflln or mixture of such parafllns is added to the hydrocarbon Such addition is often preferable to having a low-boiling paraflln hydrocarbon present while an acid phase is also present, as during the acid treatment of the normally liquid hydrocarbons. Regardless of whether the low-boiling paraflln is present during the treatment vor is subsequently.added, the hydrocarbon phase ---is fractionally distilled to remove a low-boiling fraction in which: the distilled low-boiling par-- aflin hydrocarbon carries with it the hydro.

' fluoric acid that had been dissolvedinthe hy- Such low-boiling hydrocarbons form minimum-boiling azeotropic mixtures drocarbon phase.

with hydrofluoric acid. Under the proper con-.

' ditions, the low-boiling fraction will be such an azeotropic mixture; however, in actual plantoperation's, the. control of conditions need notbe 'so close that the low-boiling fraction is ne'ces- 1 'sarily solely an azeotropic mixture? Such treat v r -'liquid state. Intimate contactingpf'the reactants with the acid is desirable and may be ef+ ment' removes hydrofluoricacid. from the norwere-made by water-washing, alkali-washing," or

35 asthrough inlet l5 and/or. through for/removal or the acid by simple fractional distillation. In

new: in temperature is'undesiral le because it promotes atendency ofhydrofluoric acid to react with. liquid hydrocarbons toform fluorine- 5 containing compounds. Nevertheless, if desired,

simple fractional distillation of the dissolved hydrofluoric acid from the treated liquid hydroca'r bon material, without prior addition {of a relatively low-boiling paraflln, may be practiced.

10 The acid removed by either type of fractional distillation is suitable for re-use in the treatment of additional hydrocarbon? material or in the alkylation of an alkylatable hydrocarbon.

' One embodiment of the invention will now be is described with reference to the accompanying exemplify some of the many'aspects of the invention.

d An alkylatable hydrocarbon, usually anisoparaflln of four. to five carbon atoms per molecule, such as isobutanefwhich is preferred, is

admitted 'to alkylator vl'l, as through inlet l|;

preferably, it is brought to the alkylator I! by I conduitTI as will be indicated hereinaften- Simultaneously, an alkylating agent, such as one or more oleilns having three to flve carbon atoms per molecule, is admitted to alkylator I! through one or more inlets, such as inlet I3. Hydrofluoric acid, which catalytically promotes the alkylation of the-allwlatable hydrocarbon by the al-.

alkylator l1," conduit 58;

kylating agent, is also admitted to the acid is advantageously as concentrated-as" possible, being preferably anhydrous, although. it

- is known to promote alkylation. even when it contains up to about 20 per cent of water.

The conditions in the alkylator may be varied widely, but they are preferably so selected as to favor alkylation and to minimize side reactions such as. reactions that consume thealkylating agent to produce relatively heavy u saturated hydrocarbons or polymers and/or fluorine-con taining compounds. To thisend, the instantaneous concentration of alkylatlng agent in the reaction mixture should'be low, so that the.'iS0-" o paratlln is always in great excess;,accordingly...-,

multipolnt addition of the alkylatinfasent to the reaction zone is advantageous. 'l'hefratio of .j

' hydrofluoric acid to hydrocarbons should be high I enough for easy maintenance of a large. acid surface: a ratio between about 1:1 and 1:10 by 5 liquid volume is generally satisfactory, but at times this ratio may be exceeded in either dire'ction. The temperature may vary widely; a temperature in thera'nge. of from about to about F. is preferred, but it may bezfar out of this range in either direction without making ;the

alkylation inoperative. The reaction period or time of contact of the'reactants with the hydrofluoric acid may vary from one minute or less to one hour or more, depending somewhat on the temperaturey atim of contact offrom about 1 to about) minutes is usually satisfactory in the preferred temperature range. A high pressure may be used, but

that necessary. to maintain. the reactants in the fected' by.'any suitdblurhedns, for example, by

mechanical agitation, such a'sagita'tion of the turbo-mixer tim which is preferred:

After 'a-suitable reaction period, .or time of the pressure-need not exceed contact, the reaction mixture'is. passed from alk-ylator ll through conduit l8 to separator 20, wherein it is separated, as by gravity and/or centriiugation, into a hydrocarbon-phase-and a relatively dense acid phase.v During'the separation, elevated temperatures preferably should be avoided, since the mutual solubility of liquid" hydrofluoric acid and hydrocarbons increases with increase in temperature; for example, in the range of 32 to 140 R, the solubility of hydrofluoric acid in isobutane increases practically linearly from 0.3 to 0.9 per cent by weight, and the solubility of isobutane in hydrofluoric acid increases from 1.8 to 4.0 per cent. For improved separation of the two phases, the temperature may be advantageously lowered somewhat below the temperature preferred for alkylator ll,

preferably to a temperature in the range or from about 10 to about 50 F., more or less.

The hydrocarbon phase separated from the alkylation mixture in separator 20 is --passed' 3' ent in the -acid} whereby this material becomes relativelmresistant, to reaction with the isobutane through conduit 29 intoi'ractionating means 23.

In this fractionating means, it is iractionally distilled into the desired alkylation products, by-

products, and recycle fractions. For example, I a low-boiling fraction comprising relatively inert gases such as propane, lighter hydrocarbons, and

some hydrogen fluoridev may ,be .withdrawn through outlet 24: if desired, this material may betreated, as in a cooler and separator; (not shown in the drawing), to condense and recover the hydrogen fluoride which then'may be re- .cycled to any appropriate step in the process. A fraction consisting predominantly of isobutime may be recycled directly to alkylator ll, as

through conduit 27, but preferably it is passed through-line 28 to isobutane treater ti; A fraction comprising chiefly any normal butane may be withdrawn from the system, as through outlet 29. A fraction comprising highly branched normally liquid hydrocarbons, which were formed by the alklationand which are suitable for use in-aviation gasoline, ay be withdrawn through outlet iii. A relative y small high-boiling fraction comprising-heavy Icy-products may be withdrawn through outlet t3.

The-acid layer separated from the alkylation mixture in separator 20 may be recycled-to al-' kylator H, as through conduits Wand F58. When it is spent to a desired degree, it may be passed through conduit 36, directly to contacting chamber 5i. Preferably, however, .it is first given a treatment with isobutane in isobutane treater M,

whereto it is brought through conduit 33. Isobutane is'adrnitted through inlet 39; ordinarily and preferably, such isobutane constitutes the major isobutane feed to the process: it is usually augmented by isobutane passing from fractionating means 2t through line 28. The isobutane and the hydrofluoric ac d in treaterjtl are in-' .timately contacted together, wherebythe isobuand produces heavy nonreactive carbonaceous compounds, some or which appear to be exceptionally high in iluorine content; consequently contacting: .within 5 minutes or-less after the separation is-preferred. p r i Treater ti may comprise any suitable means for. effecting intimate; mixing and/or emulsiflcation of the isobutane with the used hydrofluoric acid it maybe a standardniixer having a mechanical stirrer, or it may be an arrangement or piping-and/or lets wherewith turbulence is maintained byhigh fluidwelocity. 1 Alternatively, it may bedesigned for shooting a counterecurrent contacting oi the acid and the isobutane, as, for example, in a tower in whichthe isobutane' rises through the down fiowing acid but such countercurrent contacting is relatively less; satisfactory because intimate contacting oi the two liquid phases is not favoredasmuch as it is by the fine subdivision and emulsification produced by a mechanical mixer of th -concurrenttype, which accordingly is preferred. The treater ti is preferablyoperated at atmospheric temperature, i thoughaat times some heating or cooling may be advantageous and may be used. The pressure should be sumcient to maintain the mixturein the liquid phase. The treating time isnot highly critical; usually a-ti-xne in the range oifrom about 5 minutes to about 2 hours is suitable the time required usually decre'ases'with increase in temperature, andstheoptimumtime for-a selected s set of conditions may bereadily foundby trial. For best results. the treating time generally must be longer than the time 01 contact in the aikylation step, since the reactivation reaction is con siderably' slowerthan the alkylation reaction;

for this reason, the treating time preferably may lib be at least twice as long'as the time of contact in the alkylation step. However, in the present process, the best possible results usually are not necessary, so that a relatively short time shorter than the time required, for example, if the. isobutane-treated acid. were to be recycled directly to the alkylation step-is generally sats factory.

The resulting mixture is'passed from treater 81- through conduit ll to separator M, wherein it is separated, as by gravity and/or centrifui'ation,

into an isobutane phase and a relatively densev hytane becomes saturated withthe acid, some additional elm/late is formed and/or extracted by I the iscbutane and the used acid becomes partly purified or reactivated, so that it becomes some- -bon materials.

Passing oi the used acid to treater iii is prefer:

ably made as soon aspossible. i. e; substantially the hydrocarbon efliuent from the alkylat'ionstep.

a Undue-delay'in eiiecting the contacting'with iso-. butane.appears to produce undesirablechemical changes in the acid-soluble organic material presdrofluoric-acid phase. 'l'heisobutane phase is passed through conduits t5 and 21 to alkyiator i I. The hydrofluoric acid phase is passed through conduits'flh and-"W to contacting chamber st if desired, part of it may be recycled tostreater ll, 1 for: additional treatment, with isobutane, as

through conduit fit.

In .contacting chamber hi, the used hydrofluoric acid, passed thereto either from separator so through line it or, after treatment with isobutune in treater ti; from separator through line 48, is utilized for the refining of hydrocarbon material conta ning gums, resins, sulfur compounds.

oasimiiaryundesired ac d-soluble constituents. This hydrocarbon material enters treater ti.

.throughinlet or. 0rdinarily. it ls a normally liquid or a-liqu ei'l'ed hydrocarbon material, but. on,

1 occasion a low-boil ng hydrocarbon mate ial in iimmediatelyfaiter separation or the acid from 1thew atria phasemay be treated with th acid n the liquid phase. The hydrocarbon. mat r al and. the acid are intimately contact-e'd inhatch or continuous manner. If continuous, the contasting maybe concurrent, but-usually it ispreferably counter-current, so -that fifesh acidcomes acid-soluble constituents, in a manner known to the art. -Suflicient hydrofluoric acid is admitted to treater, so that under preferred conditions "of operationa liquid phase containing a major I proportion of hydrofluoric acid and a minor proportion of hydrocarbon and another liquid phase 1 containing a-major proportion oi-hydrocarbons and'a minor" proportion ofhydrofluoricacid are present. The time of contacting in treater 5| is not critical, provided that sufliciently intimate contacting is obtained to effect substantial exin contact with hydrocarbon material that has already lost-most of its content of undesirable traction of acid-soluble compounds by the acid. I

. The resulting hydrofluoric acid extract, containing acid-soluble, compounds removed from v the hydrocarbon material charged throughinlet 52, is passedfrom contacting chamber 5| through conduit to separating ineans58, wherein the hydrofluoric acid is processed to free it from the acid-soiublematerial contained in it. Ordinarily and preferably, separating means 56 consists of a fractionating column 'wherefrom purified hydrofluoricacid is distilled overhead. Although ordinarily this purified hydrofluoric acid is recycled to alkylator H, as through conduit 58, under some conditions of operation it preferably isused to fortify the acid in contacting chamber 5| by being passed, at least input, to this chamber through conduits 68 and35;-if desired, part or all of this purified acid may be withdrawn from the system through outlet-BI, From the kettle of such a fractionating column 55 is withdrawn,- as through outlet 53, a residue comprising chiefly the acidsoluble material removed from the hydrocarbon material treated in contacting chamber 5| and some heavy acid-"soluble by-products produced in the alkylation step. By maintaining the kettle temperature sufliciently high, usually not above about 380 any fluorine containingcompounds are decomposed, liberating hydrofluoric acid, so that the residuev contains little or no fluorine; the resulting residue may be burned as fuel.

The treated or extracted hydrocarbon material is passed. from contacting chamber 5| through conduit 85 and is usually passed directly through portion of dissolved hydrofluoric acid. The resuiting purified and acid-free hydrocarbon ma-' terial is recovered as a product of the process through outlet 88. A low-boiling fraction comprising the dissolved hydrofluoric acid may be withdrawn through outlet 1 I, but it preferably is recycled to 'alkylator II, as throughconduit I3 and through conduit 58, especially when it is relatively free from low-boiling paraflins other than isobutane'. I

when the hydrocarbon material treated contacting chamber 5| is normally liquid and contains substantially no low-boilin parafiins such as propane, butane, or pentane, it is'found desirable to conduct the distillationin fractionatingmeans 88 in the presence of such a low-boiling hydrocarbon as will form' a, low-boiling azeotropic mixture with the hydrofluoric acid and thereby promote separation of the acid from the purified hydrocarbon product. An amount of low-boiling hydrocarbon sufllcientto have this effect, preferably a slight excess, accordingly mal beintroduced into the system through inlet 15; it may be passe directly to conduit 81, or it may be introduced into fractionating means 88 at an intermediate point, as through conduit 18. The resulting low-boiling fraction comprising hydrofluoric acidpreferably may be recycled to alkylator I1 as already described, if the added low-boiling hydrocarbon is isobutane; otherwise,

through conduit 81; this fraction may be re-' cycled, through conduits l8 and 88 and/or through conduits I3 and 58, to contacting chamber 5| and/or alkylator' H, in proportions controlled by the valves in lines 81 and/or 88, respectively; if desired, any part of this fraction may be removed, from the system through outlet 98. A suitable low-boiling paraflln fraction may be removed from separating means 88 and may be returned to the process through conduit 82, leading to inlet conduit 15. At times it may be found that the presence of a. low-boiling paraifln in contacting chamber 5| will aid the separation of hydrofluoric acid and hydrocarbon phases in this contacting chamber 5|, whereupon a part of the low-boiling paramn in conduit 15 may be passed throughiconduit 84 to conduit 83 and contacting chamber 5|.

In some instances the purification carried out in contacting chamber 5| will be at a. tempera- J ture more or less elevated, and a preliminary separation of hydrofluoric acid dissolved in the hydrocarbon stream from this chamber may be advantageously effected by cooling this stream to atmospheric or subatmospheric temperature. Accordingly, any desired portion of this stream is passed from conduit through conduit 96;

is cooled in cooler 98 to a desired separation temperature, preferably between about 10 and about 50- F.; and is passed through conduit 89 'to separator I88, in which separation occurs into two liquid phases. The relatively dense or hydrofiuoric acid phase is passed-from separator I88 lines 68 and 61 to fractionating means 88,wherein it is freed by distillation from a; minor prothrough'conduit IM to conduit for subsequent treatment in separating means 56 as already described; if desired, any part or all of this phase may be discharged from the system through outlet I83. The hydrocarbonphase is passed from separator I88 through conduit I85 back to conduit 66 for subsequent treatment in the system as hereinbefore described. Separator I88 will also be used when the contacting in chamber 5| 7 is made in a concurrent manner instead of in the countercurrent manner specifically indicated, or

when the contacting iS. made in a batch-wise manner. I r

Although the separation by fractional distillation in the presence of a low-boiling parafiln forms a distinctaspect or feature of the invention, the process should not be restricted to such [separationin all cases; it is possible that other separation of dissolved hydrofluoric acid from the hydrocarbon stream passing in conduit may be effected in any way that is convenient or that is known to the art, as by washing with water, an alkaline solution, or the like. Such other separation may be effected in means such as separating means 88; that is, the purifiedhy-jdrocarbon material may be passed from conduit 66 through conduit I81 to separating means 86, and the purified hydrocarbon product is recovered through outlet I89, r

fur and gum-forming compounds.

Relative to the purification of a liquid hydrocarbon stock and to the separation of dissolved hydrofluoric acid from the purified material in iractionating means 68, an initial proportion of Iowa-boiling paraflin suchas normal butane may be added throughinlet at the start of the process, and thereafter this low-boiling paraflin may be recycled within the purification system as hereinbefore described. further additions of lowboiling paraffin being made only to compensate for unavoidable losses. When the hydrocarbon material fed through inlet 52 contains such lowboiling parafiin, it may be unnecessary to add additional paraflin through inlet 15; after a steady state of operation has been reached with suitable'recycle of the low-boiling paraflin, the purified hydrocarbon material recovered through outlet 89 will contain substantially the same proiectionable constituents of the nature of sulfur compounds and colorand gum-forming compounds, which comprises; mixing in 'a contacting.

chamber-such hydrocarbon material with a used catalyst, obtained from the alkylation of .at least one lowboiling isoparafiin with at least one olefin cule in the presence of a concentrated hydrofluoric acid catalyst under alkylating conditions; passing the resulting hydrocarbon-containing mixture to portion of this paraifin as that present in the material introduced through inlet '52.

Example 1 The following example illustrates some of the many aspects of the invention without necescontaining three to five carbon atoms per molea separating means; removing from said separating means a liquid phase containing normally liquid hydrocarbons substantially free from said objectionable constituents and containing dissolved hydrofluoric acid in an amount at least sufficient to form an azeotropic mixture with said dissolved hydrofluoric acid; admixing with said liquid phase a relatively low-boiling paraflinic material; passing the liquid phase and relatively lowboiling paraifinic material to a fractional distillation means; separating from said distillation means a low-boiling fraction containing at least a portion of the low-boiling parafiinic material and substantially all of the dissolved hydrofluoric acid; passing said fraction to a treating means from which hydrofluoric acid is removedtsepalayer; a relatively small proportion of isobutane is added tothe hydrocarbon layer; and the resulting mixture is freed from the dissolved acid tically negligible or undetectable content of sultilled to. purify the hydrofluoric acid, which is also passed to the alkylationstep.

Although, for the sake of simplicity and by way The distilled of example, the description herein hastbeen devoted primarily to hydrofluoric acid used as an]. alkylation catalyst,it will be understood that other hydrofluoric acid-containing alkylation catalysts, such as mixtures of hydrofluoric acid with sulfuric acid, with boron fluoride; with metalloid halides of the type of phosphorus pentafiuoride, or with other promoters or moth-- here, may be used in substantially the manner be obvious to those skilled in the art. The drawtionable constituents and containing dissolved ing is diagrammatic and does not show in detail many pieces of equipment, such as pumps ir'actionating columns, and the like, that may be desirable or necessary for obtaining the rerating also from the fractional distillation means a higher-boiling fraction containing saturated normally liquid hydrocarbons substantially tree from said objectionable constituents and from hydrofluoric acid; and removing said higherboiling fraction from the process.

2. A process of treating a hydrocarbon material A containing normally liquid hydrocarbons and ob-' jectionable constituents of the nature of sulfur compounds and colorand gum-forming compounds, which comprises contacting such hydrocarbon material with a used catalyst, obtained from the alkylation of at least one low-boiling isoparaflin with at least one olefin containing three to live carbon atoms per molecule in the presence of a concentrated hydrofluoric acid catalyst under alkylating conditions, in a contactr ing chamber and in sumcient amount to produce a liquid phase containinga major portion of the used hydrofluoric acid catalyst, passing'a mixture of hydrocarbon material and used hydrofluoric acid catalyst to a first separating means and f separating therein said liquid phase from a phase containing normallyiiquid substantially saturated hydrocarbons substantially free from said objecydrofluoric acid, passing at least a portion of the liquid phase containing a major portion of the used hydrofluoric acid catalystto a second separating means, recovering hydrofluoric acid from said second separating means and returning at least a part of. said acid to the contacting chamsuits indicated. As such pieces of equipment are well-known in principle and use, they may be readily supplied by those skilled in the art. Suitable equipment and operating conditions for any particular application of the invention maybe readily'ascertained by one skilled in the art in the light of the foregoing description and discus ents and containing dissolved hydrofluoric acid ber, admixing with the phase containing normally liquid substantially saturated hydrocarbons substantially tree from said'obiectionabie constitu- Y a'relativeiy'low-boiling paraflinic material, passsion. Because of the many modifications and a hydrocarbon material containing normally liquid hydrocarbons and obing this admixture to a fractional distillation.

also a fraction containing saturated normally liquid hydrocarbon material substantially free from saidobiectionable constituents and hydrofluoric acid and removing the saturated normally liquid hydrocarbon material substantially free catalyst being spent with respect to said alkylation reaction, in a contacting chamber, passing a resulting hydrocarbon-containing mixture to a separating means, removing therefrom a liquid phase containing normally liquid substantially saturated hydrocarbons substantially free from said objectionable constituents and containing dissolved hydrofluoric acid, admixing with the liquid phase a relatively low-boiling parafiinic 2,s7c,o7c i "centrated hydrofluoric acid catalyst, in a contacting chamber and-in suiflcient amount to form a liquid phase containing a major portion of the spent catalyst and a liquid phasecontaining a mixture of the hydrocarbonfmaterial and the remaining spent catalyst, passing said mixture I of hydrocarbon material and remaining spent catalyst to a first separating means, removin therefrom a liquidphase containing hydrofluoric acid and passing said phase along with the liquid phase containing a major portion of the spent catalyst to a second separating means wherein hydrofluoric acid suitable for reuse in the treatmaterial, passing the liquid phase and relatively low-boiling paramnic material to a fractional distillation means, separating from said distillation means a low-boiling fraction containing atleast a portion of the low-boiling parafiinic material, I and substantially all of the dissolved hydrofluoric acid, passing said fraction to a' treatin means from which hydrofluoric acid is removed, circulating said hydrofluoric acid to the contacting chamber, separating also from the fractional distillation means a higher boiling fraction containing saturated normally liquid'hydrocarbons substantially free from said objectionable constituents and hydrofluoric acid, and removing said higher boiling fraction from the process. j

4. A process of treating-a hydrocarbon material containing at least some objectionable constitumaterial and substantially. all of the dissolved.

ents of the nature of. colorand gum-forming compounds, which-comprises contacting the hydrocarbon material with a spent catalyst obtained from the alkylation of at least one low-boiling isoparamn with at least one olefin containing three to five carbon atoms in the'presence of a conment of additional hydrocarbon material is separated and returned to the'contacting chamber; removing-also from the first separating means asecond phase containing substantially saturated I hydrocarbons and dissolved hydrofluoric acid, ad-

mixing with this second phase a relatively low boiling paraffinic material in an amount at least sufficient to form an azeotropic mixture with said dissolved hydrofluoric. acid,'passing this second phase with admixed low-boiling parafllnic material to a fractional distillation means, separating therefrom a low-boiling fraction containing at least .aportion of-the low-boilingparafllnic hydrofluoric acid, passing said fraction to a' treating means from which hydrofluoric acid is re moved and circulating said hydrofluoric acid to the contact chamber, and separating from the treating means the low-boiling parafllnic material and recirculating this material to thefractional distillation means; and separating also from the treating means and from the fractional distillation means higher boiling fractions containing saturated normally liquid hydrocarbons substantially free from said objectionable constituents and substantially free of'hydrofluoric acid, and removing said saturated hydrocarbons from the process.

MARYAN P. MA'I'USZAK.

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