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Dec. 3, 1946. _ L. s. KASSEL l 2,411,996 ME‘II’HOD FOR CATALYTIC CONVERSION _ Filed April I12, 1944 , fr?" Z6 Z5 /27 by j@ j. Patented Dec. 3, 1946 'Y UNITED -STATES PATENT OFFICE METH'OD FOR CATALYTIC CGNVERSION Louis S. Kassel, Riverside. Ill.,v assignor toUni versal Oil Products Company, Chicago, Ill., a corporation of Delaware ' Application .4pm 12, 1944, serai No. 530,643 2 claims. (cl. 19e-_52) l ` This invention relates to a method for conduct ing catalytic conversions and more particularly to a method for converting hydrocarbons by con tact with suitable conversion catalysts. The invention is concerned with a method of 5 conducting conversion reactions which may advantageously be employed in various processes ior the conversion of hydrocarbons. Among the. several processes to which the invention may be applied are catalytic cracking of hydrocarbon oil, 10 catalytic reforming of gasoline boiling range ma:v ` _ 2 . . generated catalyst from the lower end oi said regeneration zone, introducing oxygen containing gas under pressure to said regeneration zone and contacting it therein with a moving bed oil cata lyst to remove the contamination therefrom by vcombustion andv employing the resultant flue gas with no increase in pressure to transfer the re generated catalyst from a point below said re generation zone to a point above said conversion zone, and to transfer the contaminated catalyst from a~ point below said conversion zone to a terials, catalytic aromatization of hydrocarbons, point above said regeneration zone. dehydrogenation of dehydrogenatable hydrocarbons,v and similar reactions for the conversion of In a more limited embodiment the transfer o catalyst by the Aflue gas from a point below the hydrocarbons. . ‘ . 15 regeneration zone to a point above the conversion The invention although adaptable for use in the above and similar reactions is especially suit- zone and from a point below the- conversion zone to a point above the regeneration’ zone is con' able for use in the process for catalytically cracking higher boiling hydrocarbon oils to form ducted in substantially straight lines. Suitable catalysts andlconditions for the vari motor fuels of high antiknock rating. . 20 ous conversion reactions which come within the One object of the present invention is to provide a method of conducting catalytic conversions scope of the invention are well-known in the art ~ and .will not be described in detail herein. How in which catalyst, in the form of solid particles is ever, to more clearly illustrate the advantages passed successively through the conversion zone which may be obtained from the use of the pres and regeneration zone in continuously moving L5 ent invention the accompanying diagrammatic beds. . ` - drawing will be explained in connection with a Another object of the invention is to provide a catalytic cracking process. , I catalytic conversion system, employing a moving Referring to the drawing, numeral I denotes catalyst bed in which the attrition of the catalyst the reactor to which vaporous hydrocarbons are and the erosion of processing equipment is held 3" charged through conduit 2 and valve 3. Reactor to a minimum. ' I when employed in a process for the cracking of Another object of the invention is to provide a method of conducting catalytic conversions by a heavy Mid-Continent gas oil will be operated at temperatures Within the range 0f about `’750 t0 means of which equipment of a given size may be 1050"- F. and at pressures of from about atmos made to process a large Yquantity of charging 35 pheric to slightly superatmospheric.' The catalyst material without sacrificing product yields or employed may be formed of granular particles quality. . - and may be composed of various natural occur Another object of the invention is to provide a ring clays or synthetic silica-alumina composites catalytic conversion system in which the heat of made, for example, by the process described in regeneration supplies a substantial portion ofthe 40 U. S. Patent No. 2,229,353- BeSides Silica-alu heat of reaction. ` -` mina, the catalyst may also include other oxides, Another object of the invention is to provide for example, oxides of magnesium, zirconium,fand a system for the conversion of hydrocarbons wherein the utility requirements are held to a titanium. Very excellent results yhave been ob tained employing a spherical shaped catalyst minimum. ' ' 45 made' by precipitating spheres of hydrated silica In one embodiment the invention concerns a method of converting hydrocarbons which comprises contacting said hydrocarbons in a zone maintained at conversion conditions with a mov.. . and impregnatlng them with alumina by soak~ ing them successively in an aqueous solution of ‘aluminum sulfate and in an alkaline precipitant. The _spheres are then `washed, aged and dried. ing bed oi catalyst, continuously introducing cat- 50 Although the preferred range of catalyst par alyst to the upper end of said zone and _continuticle size is between about 11s to ?‘g inch average ously removing contaminated catalyst from vthe diameter the invention includes within its scope lower end of said zone. continuously introducing the use of larger and smaller size catalyst par said contaminated catalyst to the upper end of ticles. The main considerations in-the selection a regeneration zone, continuously removing re- 55 of‘size are the allowable pressure drop through 2,41 1,996 - 3 the catalyst beds in the various contacting vessels and the ability of the carrying gases -to transport the catalyst between the diñerent vessels. The reaction products from reactor I are con 4 - . from the system through valve 28 or it may be directed by means of conduit 4I' and valve 42 to conduit I8 to transport contaminated catalyst withdrawn from the reactor to disengaging chamber _I1 as has already been described. In ducted through conduit 4 and valve 5 to suit chamber 30 the catalyst particles fall by gravity able separating and recovery equipment not to hopper sectionßl wherefrom they pass by shown. Catalyst is introduced to reactor I by means of conduit 8 into reactor I,_thus complet means of conduit G and withdrawn therefrom by , ing the- cycle. `Chamber 30 like chamber I1 may conduit- 1. Within the lower portion'of the re actor is placed a cone-shaped member 8 which 10 be provided with a baille 32 which functions to may consist oi" a perforated plate or screen ' which serves as a distribution means for the'in substantially prevent catalyst parties from be ing withdrawn from the chamber by means of conduit 35. ' coming reactant stream. _Inlet condut 8 for sup The pressure in reactor I is ‘normally higher plying the regenerated catalyst to the reactor ex tends some distance below the upper head of the 15 than in disengaging chamber 30. In order to prevent reaction products from iiowing up reactor to provide a separation space for the re through conduit 8 into chamber 30 and ultimately action products leaving the' catalyst bed. being lost with the spent regenerating- gas, a Below reactor I and connected thereto by con stream of splitting iluid is provided. This stream. ' duit 1 is stripper .9 through which the catalyst particles are passed in contact with a suitable 20 enters conduit 6 by valve 3_4 and line 33. The quantity of the> splitting stream is regulated so stripping iluid, such as steam, ilue gases, or that the pressure at the junction of line 33 and other inert material -to remove vaporizable con conduit 8 is higher than that in reactor I. The taminating materials‘from the catalyst to pre splitting stream therefore fiows'away from the vent their loss by combustion in the regeneration zone. Stripper 9 is similar in constructionto 25 junction in both directions, and provides a pos itive seal against mixing of reaction products and reactor I and is supplied with a stripping iluid regeneration gas. This splitting stream may be introduced by means of conduit _ I0 and valve Il. 'I‘he stripping fluid plus any materials ,re any inert gas or vapor, such as nitrogen, helium _ or steam. As a practical matter, steam is pre moved from the catalyst'is withdrawn through conduit. I2 and valve I3 and directed to suitable 30 ferred on economic grounds. The following discussion of pressure gradients recovery equipment not shown. The“ stripped is supplied in order to clarify the method of op-catalyst is withdrawn from the bottom of strip per! by means of conduit I4 controlled by valve eration. The air which enters the process by -or adjustable orifice I5. The catalyst passing conduit 25 and ultimately leaves as regenerating through valve I5 is commingled in conduit I8 35 gas by conduit I8 can take any one 0f three paths through the plant. It can flow up through re with a carrying gas produced as> will hereinafter _generator 22 and conduit 2'I into chamber I1 and be described, and passes therewith into disengag . thence 'out' through line I8. It can ilow through ing chamber I1. The catalyst particlesare sepa the lower conical section of regenerator 22 and ' rated from the carrying gas in chamber I1, the gas leaving the system through conduit I8- and 40 the distribution section 23 into conduit 28 and the catalyst particles falling to the bottom or thence by, valve 29, conduit 39, chamber 30, con- ‘ ' hopper section I9 of the disengaging chamber. duits 35,- 4I and I8 and chamber I'I to line I8. Or it can take the desired path through regenerator A baille plate 20 is provided in disengaging cham ber I1 to prevent catalyst particles from entering 22, conduit 21, conduits 31 and 39, chamber 30, ~ conduit I8 and being removed thereby from the conduits 35, 4I and I5 and chamber I1 to line I8. system. 'I'he contaminated catalyst flows from The amount of air which takes the ilrst undesired path is made small by making conduit 2I of chamber I1 by means of conduit 2| into regener . great enough height and small enough diameter ator22. Regenerator 22 is similar in construc ' so that the frictional pressure drop of gas flow` . tion to the reactor and stripper vessels being pro vided with a distribution member 23 and a sepa 50 through the catalyst mass in this conduit pro ration space 24 for emuent gases. Air is sup- ’ ' vides an effective ilow resistance. 'I'he quantity of air which takes the second undesired path is ' plied to the regenerator by means of conduit 25 likewise made small by provision of suilicient ' controlled by valve 28. resistance infconduit 28. The' major part 0f the The temperature maintained~ >in regenerator 22 will be higher than the temperature maintained 55 air stream 4is therefore constrained to take the in reactor I. The magnitude of this difference A portion of the stripping fluid will likewise will vary with the charging stock to be convert- v flow down through conduit I4, and here again ed and the particular product which may bede this undesirable tlow is minimized by proper de sirable. In general, however, this differential ' will vary from about 50 to 150° F. The air sup 60 sign of conduit- I4. Any of these undesired ñows could be com plied to regenerator 22- removesthe contamina pletely prevented by the use of a splitting stream tion from the catalyst by combustion and the resultant flue gas is withdrawn from the regen such as is shown in conduit 8. In most cases, erator by means of conduit 21 and maybe di however,- _this would not be particularly advan verted to conduits I 8 and 39 respectively by 65 tageous. From the drawingit can readily be ~'seen that f means of valve 40 and conduit 31 and valve 38. the only conduits carryin'g‘high velocity catalyst The regenerated catalyst is removed from the regenerator by means .of conduit 28 controlledparticles conduct them in a' substantially straight by valve or adjustable orifice 29.l The catalyst line flow which, of course, will limit erosion of passing through valve 29 is commingled with ilue 70 the line and attrition of the catalyst particles to Vgas passing through' conduit 39 and is transport ed thereby to catalyst disengaging chamber 35 , In order to further illustrate the utility of the wherein the catalyst is separated from the ñue -process the following example is included in this specification: . gas. The ñue gas is withdrawn from chamber 88 by means of conduit 35 and maybe removed 75 ^ A 31.2° API heavy Mid-Continent gas oil is desired path. a minimum. _ ' _ ' y _ _ t 2,411,996 . 5 j vaporized and introduced to reactor I which is zone maintained at combustion temperature to maintained at an average temperature of 975° F. burn contaminants from the catalyst particles, The catalyst used is a spherical shaped silicasupplying regenerated catalyst particles by grav~ alumina composite having a particle size oi' about ity to the upper portion of the reaction zone from 11g inch diameter. `The oil is charged at a rate 5 a separating zone disposed lat a higher elevation equivalent to a weight hourly space velocity of than the reaction and regenerating zones, sup ` 8.5 (8.5 pounds of oil per pound of catalyst in . plying contaminated catalyst particles by gravity the reaction zone) and the catalyst is circulated to the upper portion of the regenerating zone at a catalyst to oil weight ratio ‘of 3.2 (3.2 pounds of catalyst entering the reaction zone to each pound of'oil). from a second separating zone disposed at a The resultant product contains a higher elevation than the reaction and regener ating zones, removing contaminated catalyst motor fuel having a clear ASTM octane num ber by the motor method of 82.5. The yield of ' this gasoline on a once through basis is 38.8 vol urne per cent of the gas oil charged. The con 15 with‘drawn regenerated catalyst particles up version obtained based on the per cent of dis appearance of the gas oil charged is 54.7. wardly to the vfirst-'named separating zone in sus pension in combustion gases formed in the re from the lower portion of the reaction zone, re moving regenerated catalyst from the lower por tion of the regenerating zone, transporting the From this example it can readily be seen that generating zone, separating the regenerated par the present invention oiïers a process by which ticles ‘from the combustion gases in said iìrstu large quantities of charging material may be conf 20 named separating zone, suspending in at least verted to a highly desirable product in relatively `a portion of the thus separated combustion gases small and inexpensive equipment. . \ the contaminated catalyst removed from the lower portion, of' the reaction zone, passing the resultant suspension upwardly into saidv second separating zone and therein separating the con taminated catalyst from the combustion gases. 2. The process as deñned in claim 1 further characterized in that the regenerating zone is maintained under a pressure such that the pres Also by employing the present invention veryv e?cient and economical transfer of catalyst be» tween the various processing' zones is accom plished, the incoming regenerating air under moderate pressure supplying all the necessary lifting power. ‘ l ' I claim as my invention: 1. A conversion process which comprises con tacting hydrocarbons with subdivided solid cata-= 30 sure of the combustion gases'kiischarging there viyst in a reaction zone maintained under con version conditions, simultaneously passing an' oxygen-»containing gas through a mass oi' con taminated catalyst particles in a regenerating 35 from is sumcient to overcome the flow resistance in_said‘ transportation „of the catalyst, the latter being transported as aforesaid under the pres sure of the regenerating zone. . LOUIS S. KASSEL.