Патент USA US2285727код для вставки
June 9, 1942. v_ |_ KOMAREWSKY v2,285,727 TREATMENT 0F GASOLINE Filed Jan. .'50,> 1959 / 2/ , s @ASE OUS PROD'UC 71s ¿SEPARA TION“ Z ONEJYJ. f_. _ 5 ' n 6 ¿22% ' 2,285,721 estema June 9, 1942 UNITED STATES PATENT oFFlcE TREATMENT 0F GAS OLINE .Y ‘ Vasili I. Komarewsky,` Chicago, Ill., assignor to Universal Oil Products Company, Chlcago,'lll., a corporation of Delaware , , Y Application January 30, 1939, Serial No. 253,603 (C1. 196-49) 17 Claims. This invention relates particularly to the treat ment of gasolines of inferior knock-rating to im ' step to further treatment with catalysts effective in dehydrogenating and producingfcyclic com pounds from the parailln hydrocarbons. prove them in this respect and is specially con- 1 cerned with a catalytic treating process for ac complishing this object. ' It is within the scope of the invention to em 5 ploy different catalysts in the two stages or to employ the same catalyst with the temperature and other conditions so that the dehydrogena tion 'of the naphthenes is brought about in the primary stage withv substantially no eñect ¿on While the'proces's to be disclosed is primarilyl adapted to the treatment of straight-run gaso line's produced by the simple distillation of crude oils, it may be also applied under suitably modi ñed conditions of operation to cracked gasolines 10 aliphatic hydrocarbonswhile the -said aliphatic hydrocarbons are dehydrogenated and cyclicized in conjunction with the cracking process to in in the second stage under moreïsevere conditions crease the overall e?ñciency thereof. ’ "i of operation in regard to temperature and time‘of Apart from the small amounts of contami contact. This point will be developedfin later nating compounds containingV sulfur, nitrogen, and oxygen which are present in varying amounts 15 in straight-run gasolines, extensive analyses for The process of the present invention -is to some extent based on thefact that the conditions and hydrocarbon groups have shown that straight catalysts best » employed for dehydrogenating run gasolines consist essentially of mixtures of 6-carbon atom naphthene hydrocarbons and var_i naphthenes are sharply differentiated from those ous parañin hydrocarbons in varying proportions. 20 which are best for dehydrogenating and cycliciz ‘ ing straight chain hydrocarbons. Whereas cata-ï 'I'he group analyses thus far madel do not gom pletely distinguish between naphthenes of 5, 6, ~ lytic reforming processes are known for improv ing the antiknock value of gasolines inferior in and 'l carbon atoms inthe ring orbetween par this respect, substantially all of‘these processes amn hydrocarbons of normal or branched chain structure, _but for the purpose of the present de 25 operate in a single stage with a‘selected catalyst under average conditions which are foundgby scription of a 'process applicable to improving the knock rating of these gasolines, they may be ~ trial to produce the best overall results but usually considered as consisting of varying proportions not the 'optimum for the treatment of the vdii examples. v of cyclo-hexane and its alkylated derivatives on ' f Y ' ferent hydrocarbon groups separately. . For ex the one hand and the various normal paraiiln 30 ample, cyclo-hexane and other naphthenes are hydrocarbons ranging from approximately 5 to readily- dehydrogenated to benzol and its al 12 carbon atoms to the molecule on the other kylated derivativesy by contacting >their vapors with nickel or other members of the iron group It is a known fact that in general the more at temperatures of the order of 250-300’ C. 'I'hese 35 highly unsaturated compounds of a given mo conditons, however, are usually without material lecular structure have a higher antiknockyalue efl’ect upon paraiiin hydrocarbons of gasoline boil hand. . ' ' than the saturated compounds. VIt is further ing range and if conditions oi' increasing severity are employed'with the same catalysts, the par generally higher antiknock value than straight aiilns show a greater tendency to -sui’ñer carbon chain compounds of asimilar >number of `carbon 40 to-carbon splitting and the formation of unde known in general that cyclic compounds have a atoms unless the latter are of a branchedchain or isomeric structure. 'I'he process of the pres ent invention utilizes both of these facts in con verting in the most selective and generally ad vantageous manner substantial proportions of the naphthene content of gasolines into aromatics and substantial proportions of the paraffin con tent into oleflns and aromatics as will be herein after more fully disclosed. In one speciiic 'embodiment the present in vention comprises a process for improving the sirably‘large amounts of gases and heavy liquid v byproducts. 45 As previously intimated, it is within the scope of the invention to use other catalysts than nickel or the other members of‘V the iron group in the first stage and these catalysts may be of'a mixed character such as, for example, alumina support ing both nickel and chromium sesquioxide. In the manipulation of the process with such cata lysts it is possible to regulate conditions so‘that substantially only naphthenes are dehydrogenate'd in the 'primary stage, the temperatures usually first subjecting the gasoline to contact with cata employed for thîsbelng of the orderoi 35o-450° lysts eiïective in dehydrogenating the naphthenesl and then subjecting the gasoline from the first 55 C. depending upon the percentage of naphthenes anti-knock value of gasolines which comprises 2 . 2,285,727 , hydroxides or carbonates furnish suitable sup present and the activity of the particular cata lyst employed. ports for the catalytic oxides and a catalyst Ifv catalysts are employed which are primarily which has given excellent-service consists of effective in dehydrogenating and cyclicizing the granular activated alumina supporting minor parañin and other straight-chain hydrocarbon compounds present in admixture with naphthenes proportions (usually 15-20% by weight) of chro mium sesquioxide. The temperatures employed in a given gasoline, the conditions employed are in the second step are preferably somewhat higher thvan'thos’e employed in' therprimary stage usually too severe for the simple dehydrogenation of naphthenes and the catalysts furthering the of the process and are usually 450° C. or higher, reactions cf the parafiins are not as speciñc in 10 this combination of temperature and catalyst being substantially without effect on the aro their dehydrogenating effect upon naphthenes as matic hydrocarbons produced from the first the nickel and other materials mentioned. vThe present invention comprises therefore the step stage.V binations ofcatalysts and conditions specific to the dehydrogenation of naphthenes and secondly those catalysts and conditions which tend to cause dehydrogenation and dehydrocyclization of par afñns. ' ~ ~ For-the dehydrogenation of naphthenes, nickel, ’ ' The accompanyingv drawing is a flow diagram of the process of vmy invention. The naphtha wise aromatization of gasolines using first com- ' ` charging VVstock'isV supplied to tne vsystem by way of line l from which it is Ydirected to the first dehydrogenating zone indicated by 2 in the draw » ing.t In this zone the hydrocarbonsare sub 20 jected to> contact with a dehydrogenating cata cobalt and iron have already been mentioned, but it is within the scope of the invention toV lyst under conditions effectivefin the dehydro employ if desired more expensive materials such hereinbefore set forth, >the temperature' of the as the members of the platinum group, including catalyst in this stage is of the order of 25o-450° C. genation of naphthenes to form aromatics. . As platinum, palladium, iridium, osmiurn, etc. In 25 while utilizing suchcatalysts as 'nickel on` sup porting materials such as kieselguhr or other the operation of the process, best results“ are substances ofsiliceous’ ' or alumin'ous character. usually obtained when these metals are used on relatively inert granular supports to present a _ The products of this `dehydrogena‘tion’'zone are removed byway of line 3 and,_if desired, may larger `catalytic surface due to their extensive distribution. Various types of supporting mate 30 be directed to a separation zoneY No. 1, ,indicated by 5 in the drawing.V Inthis separation zone, rials of a siliceous or alurnîrifous character may hydrogen together with smaller quantities' of be kieselguhr employed andasother carrierssuch forms of silica, as, forclays, example, and' s normally gaseous hydrocarbons is removed from other silicates, alumina, either naturalbr‘pre pared and other inert materials. In the treat 35 ment of most gasolines with such catalysts, tem peratures of approximately300° C. are employed in the first stage, thegasoline being vaporized the 'system' by wayfofI line 6." If 1desi'red, this separation vstep may be omittedand the reaction products from the first dehydrogenation zone in .this case are directed from line 3 to'iline I which connects with line l, rsi'ipplying the second dehy drogenation zoneindicated by B in the drawing. andpas'sed over a selected and active dehydro genating metal catalyst at a rate commensurate 40 y In'the second dehydrogenation‘zone the'v par aillns are Yldehydrocyclici‘z'ed to form aromatic with obtaining best results in converting the naphthene ~content into aromatics.v Obviously hydrocarbons. The temperature in the second the exact conditions of‘operation will be deter zone lies within the approximate rlimits of 450 mined by the amount and’character of the naph l750" C. Effective catalysts in the' second zone treated. 'supported >on refractory materials-such’as alu thenes present in whatever gas mixture is being 45 comprise particularly group 5 and group 6 oxides ' „ ’ ` After the aromatization of 'the naphthene con ‘ mina.` GroupV 4 oxides `have'also been used> but tent, the type of catalyst is changed and the in general are regarded as less electiveA than vapors with or without separation of hydrogen such oxides as those'of vanadium, chromium and and other reaction products are contacted with 50 molybdenum. The products 4from the second catalysts which have a dehydrogenating and dehydrogenation zone"v are directed by way of line 9 to a`second separation zone indicated by cyclicizing activity with respect to residual par añin hydrocarbons. Catalysts of this character l0 in the drawing. Inthis second separation zone, hydrogen and normally gaseous. hydro include generally compounds and particularly oxides of the elements in the left-hand columns 55 carbons are separated from -,the stabilized gaso .line which constitutes the product ofthe process. of groups 4, 5, and 6 of the periodic table, includ ing titanium, zirconium, cerium, hafniurn,'tho- It is usually found desirableto rerun the stabi lized gasoline in order toreduce the "quantityof rium, vanadium, columbium, tantalum,- chro mium, molybdenum, tungsten, and uranium. Such catalysts are readily prepared by deposit gum formingconstituents present therein. '. ` ing nitrates or other salts or hydroxides of the elements on miscellaneous supports and’calcin ing and reducing with hydrogen or‘hydrocarbons to produce the lower oxides. The optimum percentages of these oxides which are suitable for . Thejfollowing example- is given to ¿indicate the advantages of. thejpresent type fofprocess in .im proving the antiknock value of vstraight run gaso lines, although it will be'understood 'that cata lysts and conditions willbe considerablyV niodiñed in thecase ofl other gasolineslso that the exam effecting the desired dehydrogenation and cycli cizing~of mixtures of paraffin hydrocarbons will ple `is not intended to4 place'undue limitations y obviously vary with the amount and character A Pennsylvania straight run gasoline fraction boiling between 100 ,and 150° Cfa'ndhavingan of the paraffin hydrocarbons and the lactivity of the particular oxide promoter. However, a on the scope ofthe invention. . , l octanenumber by the motor method of 43' .was few trials will determine which is the most effec tive in a given instance. Granular activated treated by three'different procedures as follows: V.aluminas prepared from precipitated aluminum sistingof reduced nickelon alumina'at atem (l) vVapors were passed noverjacatalyst con ' perature of 300‘7 C. .and substantially atmospheric hydroxide by calcination methods or by similar treatment of some'naturally occurring aluminum 75 pressure. After this treatment, >it was found by 2,285,727 analysis that the percentage of aromatic hydro carbons was 36.5 and that the octane number 4. A process for the treatment of >gasoline to „increase the antiknock value thereof which corr prises subjecting- vapors of said gasoline in a first stage to contact `with a catalyst containing has been raised to 51. The gas evolved consisted of 95% hydrogen. ' 3 - a metal 'effective in dehydrogenating naph thenes, and in a second stage to contact with a After separation of hydrogen the product of the first stage was passed over an alumina chromia catalyst at va temperature of 45,09 C. catalyst containing a metal oxide effective in n and analyses indicatedrthat the percentage of dehydrogenating and cyclicizing parafl‘lns. y 5. A process for the treatment of'straight run aromatics had been increased to 55 and the octane number raised to '15.L The gas evolved in the second stage was 92% hydrogen. gasoline to increase the antiknock value thereof (2) A catalyst was prepared which contained both nickel and chromium oxide on alumina and thevapors of the gasoline fraction were passed 15' over this catalyst vat a temperaturer of 450° C. to simulate a one-stage reforming operation.~ This treatment produced an aromatic vcontent of 45% which comprises subjecting vapors of said gaso line in a first stage to contact with la catalyst containing a metal effective indehydrogenating naphthenes,4 and in a second stage to contact with a catalyst containing a metal oxide `effec _tive in dehydrogenating and cyclicizing paraflins. evolved contained 85% hydrogen. rIt will be seen 6. A process for the treatment of cracked gas 'oline to increase the antiknock value thereof which comprises subjecting the vapors of said by this test that poorer results were obtainedbyg combining the catalyst and using a single se lyst containing a metal effective in dehydrogen lected temperature for _the reforming operation. ating naphthenes, and in a second stage to con and raised the octane number to 65. The gas gasoline in a first stage to contact with a cata tact with a catalyst containing a metal oxide (3) Using `an .alumina-chromia-nickel cata effective in dehydrogenating and cyclicizing lyst, the vaporized gasoline fraction was treated at 405° C. to increase the aromatic contentl to parafìlns. _ - 7. A process for'the treatment of ' gasoline to increase the antiknocky value thereof which com prises subjecting vapors of said gasoline in a first stage to contact at a temperature of the 45% and raise the octane number to 57, the gas evolved consisting of 94% hydrogen. In the sec ond stage the products were passed over the same catalyst at 450° C., the yield of products consist ing of 60% aromatics and having a 75 octane 30 order of Z50-350° C. with a catalyst containing a metal eiîective'in dehydrogenating naphthenes, Vnumber, and the gas evolved consisting of 91% and in a second stageto contact at a tempera hydrogen. ture of the order of 45o-750° C. with a catalyst It will _be seen from the immediately preceding containing a metal oxide effective-in dehydro data that better results were obtained with an "alumina-chromia-nickel catalyst when the aro- ' matization of the gasoline was conducted in two stages as in section (3) since the octane number obtained was 75 whereas that obtained in the single-stage treatment under section (2) was only 65. genating and cyclicizing paramns.l ` 8. A process for the treatment of straight run gasoline tó> increase the antiknock value thereof which comprises subjecting vapors of .said gaso line vin a first stage to contactA at a temperature 40 of the order of 25o-350° C. with a catalyst con taining naphthenic and aliphatic hydrocarbons taining a metal effective in dehydrogenating naphthenes, and in a second stage to contact at a temperature ofthe order of 45o-750° C. with to increase the antiknock value thereof which a catalyst containing a metal oxide eñective in I claim as my. invention: 1. A process for the treatment of gasoline con-- comprises subjecting vapors of said gasoline in 45 dehydrogenating and cyclicizing parafllns. 9. A process for the treatment of cracked a first stage to contact at a temperature of the gasoline to increase the antiknock value thereof order of 250-450° C. with a catalyst effective in which comprises subjecting the >vapors 4of said dehydrogenating naphthenic A hydrocarbons and cracked gasoline in a first stage to contact at a in a second stage to contact at a temperature within the range of 45m-750° C. with a catalyst 50 temperature of- the order of 25o-350° C. with a effective in dehydrogenating and cyclicizing ali phatic hydrocarbons. ‘ ' 2. A process for the treatment of straight run Agasoline containing naphthenic and aliphatic catalyst containing a metal effective in dehydro genating naphthenes, and in a second stage to contact at a temperature of the order of 450-750" C.' with a catalyst containing a metal oxide effective in dehydrogenating >and cyclicizing hydrocarbons to increase the antiknock value 55 _ parafllns. thereof which comprises subjecting vapors of 10. A process for the treatment of gasoline to increase the antiknock value thereof which com prises subjecting the vapors of said gasoline in a lyst efïectivé- Ain dehydrogenating naphthenic first stage to contact at-“a temperature of the 60 hydrocarbons and in a second stage to contact said gasoline in a first stage to contact at a tem perature of the order of Z50-450° C. with a cata at a temperature within the range of 45,0-'750° C. with a catalyst effective in dehydrogenating and cyclicizing aliphatic hydrocarbons. -order of Z50-350° C. with a reduced nickel cata lyst effective 'in dehydrogenating naphthenes, and in a second stage to contact at a tempera ture of the order of 450~750° C. with a catalyst 3. A process for vthe treatment of cracked gas containing a metal oxide effective in dehydro oline containing naphthenic and aliphatic hy 65 genating and cyclicizing parai‘llns. drocarbons to increase the antiknock value thereof which comprises subjecting vapors of 11.- A‘process for the treatment of gasoline to increase the antiknock value thereof which com prises subjecting the vapors of said gasoline in 70 a first stage to contact at a temperature of the catalyst effective in dehydrogenating naphthenic order of 25o-350° C. with a reduced nickel ca* hydrocarbons and in a second stage to contact lyst eñective- in dehydrogenating naphthenes,v at a temperature within the range of 45o-'750° and ln a second stage to contact at a tempera C. with a catalyst effective in dehydrogenating ture of the order of 450-750°7C. with a catalyst said gasoline in a first stage to contact at a temperature of the order of 250-450° C. with a and cyclicizing aliphaticl hydrocarbons. . consisting essentially of granular activated alu , 2,285,787 15. A process for »increasing the anti-knockl mina- supporting chromium sesquioxide effec 4 value of gasoline distillate: containing naph tive in dehydrogenating and cycliciaing paraiiins. thenic and aliphatic hydrocarbons which com-i prises contacting the distillate with a dehydroà. 12. A process for the treatment of gasoline `to n increase the antiknock value thereof which com- » prises subjecting the vapors of said gasoline in a ñrst stage to contact at a'tcmperature of the order of 250-350 C. with a reduced nickel cata genating catalyst under dehydrogenating oon mina' supporting vanadium sesquioxide effective in dehydrogenating and cyclicizing paramns. value of gasoline distillates containing naph ditions'selective for the conversion'of naphthenes` to aromatics, and thereafter subjecting the thus partially aromaticized distillate to catalytic de lyst eiïective in dehvdrogenatingl , naphthenes, hydrocyclization to produce further quantities and in a second stage to contact at a tempera ture of the order of 450-750° C. with a catalyst 10 of aroinatics- from the aliphatic hydrocarbons. 16. A process for increasing the anti-knock consisting essentially of granular activated alu thenic and aliphatic hydrocarbons which com prises contacting the distillate with a dehydro genating `cataLvst under dehydrogenating condi tions .selective for the conversion of naphthenes to aromatica, and thereafter subjecting the thus partially aromaticized distillate to further con tact with dehydrogenatingcatalyst under con lyst effective in dehydrogenating naphthenes, andA in a second stage to contact at a tempera 20 dltions selective for the dehydrocyclization of 13. A process for .the treatment of gasoline to increase the antiknock value thereof which com -15 prises subjecting the vapors of saidgasoline in a ñrst stage to contact at a temperature of the order of 25o-350° C. with a reduced nickel cata-V ture of the order of 450-'150’ C. with a catalyst ' . aliphatics into aromatica. 1'7. A process for increasing the anti-knock consisting essentially of granular activated alu mina supporting molybdenum sesquioxide effec tive in dehydrogenating and cyclicizing paraiiins. value of~ gasoline distillates containing naph increase the antiknock value thereof which com genating catalyst under dehydrogenating condi tions selective for the conversion of naphthenes thenic and aliphatic hydrocarbons which com 14. A process for thertreatment of gasoline to 25 prises contacting the distillate with a dehydro prises ‘subjecting the vapors of said gasoline in a _first stage to contact at a temperaturel of the order of 35o-450° C. with a composite catalyst comprising essentially arelatively inert mate v rial supporting chromium sesquioxide and re duced nickel to dehydrogenate naphthenes and. to aromatica, and thereafter subjecting the thus partially aromaticized distillate to further con 30 tact with an additional quantity of said dehy drogenating catalyst under conditions selective for the dehydrocyclization of aliphatics .into aromatica. in a second stage to contact with a separate por tion of the same catalyst at a temperature of the order of 45o-'7509 C. t0 dehydrogenßte and 35 _ cyclicize aliphatic hydrocarbons, VASILI I. KOMAREWSKY.