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Nov. 26, 1946. _ I E, D, REEVES v 2,411,592 FLUID CATALYST REACTOR Filed Oct. 31, 1942 ‘ 2 Shasta-Sheet 1 ' - co TTR£LL "AC/791754702 alséwcaa'lua ‘ c/mmz/ . 4 | éa NYlRS/t)” ZONE “I D TLATE RIGINIKATION ' CHAMBER ’ Qx Nov. 26,_ 1946. E, D; REEVES 2,411,592 ' mm) CATALYST REACTOR Filed Oct. 31, .1942 2 Sheets-Sheet 2 STANDPIPE 2I M IML‘T Patented Nov. 26, 1946 * 2,411,592 _ UNITED STATES PATENT OFFICE, 2,411,592 _ FLUID CATALYST REACTOR Edward D. Reeves, Cranford, N. J.,_assigno'r to Standard Oil Development Company, a corpor ration of Delaware Application October 31, 1942, Serial No. 464,085 ‘ 7 Claims. (01. 260—-680) 2 1 therefrom, regenerating the catalyst in a sepa rate regeneration zone, and returning the re generated catalyst to the reaction zone for fur The present invention relates to improvements , in a process of and apparatus suitable for carry ing out reactions involving solids and gases and, ther use in the process. A great deal of research more particularly, it relates to an apparatus in which a gas and a solid in powder form may be 5 has been directed toward improving the latter type of process which has come to be known as contacted under reaction conditions where said the ?uid catalyst type of operation. reaction causes deposition of contaminants on My present process relates to improvements in the catalyst, the apparatus being adapted to pro apparatus suitable for carrying out the ?uid cat place in one portion of the apparatus while the 10 alyst type of operation, and in its essence it in volves an elongated vertical chamber of vre regeneration of fouled catalyst takes place in stricted cross sectional area, disposed and divided another portion of said apparatus and is further into two contiguous compartments, in the upper provided with means for returning regenerated of which the conversion reaction takes place, catalyst to the reaction zone so that the operation ,vide means for causing the main reaction to take 15 while in the lower compartment the catalyst is ' may be performed continuously. In a great many chemical reactions, the pres ence of a solid catalyst in contact with reactants regenerated and returned to the upper compart ment. Certain necessary apparatus and com ponent parts are aililiated with the compartments in vapor or vapor-liquid phase greatly improves just mentioned in order to provide maximum eili- ' the operation, particularly from the standpoint of quality of the product. For example,‘ in gas 20 ‘ciency, all of which will more fully appear herein after from the ensuing claims which are to be oil cracking, the presence of a catalyst such as read in connection with the accompanying draw an acid treated clay of the bentonite or mont ings. _ morillonite type in the gas oil vapors undergoing The main object of my present invention is to cracking greatly improves the octane number of ‘ the gasoline produced by cracking. In certain 25 ‘provide a compact and e?icient apparatus in other reactions'such as the dehydrogenation of ole?ns to form diole?ns, the presence of a suitable catalyst such as that disclosed in the application of Kenneth K. Kearby, Serial No. 430,873, ?ied February 14, 1942, now U. S. Patent 2,395,875, 30 dated March 5, 1946, makes possible the produc tion of certain desired ole?ns and diole?nsin good yields. . In the early stages of solid catalytic treatment which catalytic reactions involving powdered catalyst may be carried out continuously with a minimum amount of equipment and utilities. A more speci?c object of my invention is to af ford facilities for the proper regeneration of cat alyst fouled during contact with the reactant va por in a regeneration zone which is contiguously disposed below the reaction zone and permits the flow of fouled catalyst by gravity from the con of hydrocarbons 'for one purpose or another, the 35 version'zone into the regeneration zone. I- attain these objects by means illustrated in catalyst was disposed in the form of a stationary the accompanying drawings in which bed in a reactor and the hydrocarbon oil was Fig. I is a vertical diagrammatic showing, part vaporized and forced through the bed of catalyst ly in section of my improved reactor and its im at reaction temperatures, whereupon the desired conversion took place. However, in this type of 40 mediate accessory apparatus; Fig. 11 is a modi ?cation of Fig. I, in which I show a standpipe to operation deposits were formed on the catalyst cause circulation of catalyst. which eventually necessitated discontinuing the Similar reference characters refer to similar productive phase of the operation and treating parts throughout the views. the catalyst with a substance adapted to remove the contaminants and restore the catalyst activ 45 Referring in detail to Fig. I, I represents a conversion chamber and .2 a regeneration cham ity, because when the catalyst had acquired a ber integral therewith and together forming a maximum amount of the contaminating sub vertical cylindrical pipe or shaft separated, how stance deposited as a result of the reaction, its activity was impaired.‘ Later in the development‘ ' ever, into the two chambers or compartments by of these catalytic processes of the type indicated, I 50 a grid plate 3 disposed as shown about the mid vertical point of the said cylindrical shaft. Dis it was found that they could be operated con posed at the upper end of the vertical shaft and tinuously by suspending a powdered catalyst in integral therewith is a disengaging chamber 4 of ‘. the vapors, forcing the suspension through a re greater internal diameter than the conversion action zone, withdrawing the reaction products from the reaction zone, separating the catalyst 55 chamber immediately below. There is also dis 3 9,411,009 posed in an upper portion of disengaging cham ber 4 a suitable ‘dust separator such as a Cottrell precipitator l0 shown diagrammatically. At the ' bottom end of regeneration‘zone 2, I provide a out oi’ powdered catalyst occurs to the extent that when the vapors reach the Cottrell precipi tator [0 they contain only about 0.0025 pound of catalyst per cubic foot of vapor or less. The va suitable feeding mechanism for the ?owing pow 5 pors still containing, however, a small amount dered material in the bottom of the chamber. of catalyst pass through the Cottrell precipita In the illustration, 1 have shown'a screw con veyor IS. The screw conveyor discharges pow tor and are withdrawn through line 50. The re action product in line 80 may be processed by distillation and solvent treatment to recover the butadiene and to recycle unreacted ole?ns in equipment not shown. The puri?cation and re covery of butadiene does not form an integral part of this invention and it may be accomplished in apparatus not shown. The catalyst which descends through the grid plate 3 into regeneration compartment 2 is dered material into a suitable mixing device such as an ordinary injector where it is intermixed with steam discharged into said injector through a pipe 2| where it forms a suspension of the pow ‘der in the steam, and this suspension is then carried by a pipe 25 into the upper part of con version chamber I. The reactant is discharged into the lower portion of the conversion com partment through a pipe 21, and a diluent if used may be discharged into reaction compartment through line 28. The inlet pipe 21 and line 28 treated by steam entering through lines 40 and ' 4|, and in the case or butene dehydrogenation employing the catalyst mentioned above, the may be made mutually intercommunicating by 20 tarry and cokey contaminants undergo water-gas a valve 30. I have also provided means for in troducing steam or some other stripping gas into the bottom of the regeneration chamber 2 as through lines 40 and 4|. If desired, air may be reaction to form C0 and CO2, thus consuming the contaminants on the catalyst and purifying the same. These gaseous products of regenera tion, together with steam, pass upwardly into the introduced into the bottom 01' the regeneration 25 conversion zone, but in the case of butene de chamber through lines 40 or ll. hydrogenation they in nowise interfere with the Having generally described the essential ele reaction and, moreover, when they are with ments of my improved apparatus, I shall now set drawn with the reaction products through line forth an example illustrating the method in which 50 they may be readily separated from the reac 30 tion products, for example, by caustic soda or poses of illustration that reactant material intro sodium carbonate, or a combination of these, or duced into the reactor through line 21 is a C4 otherwise removed in known‘manner. It is not it may be employed. It can be assumed for pur hydrocarbon fraction containing butylenewhich satisfactory, according to best practice, to regen I desire to be dehydrogenated to butadiene'. The erate the catalyst in regeneration chamber 2 with feed stock entering through line 21 is at a tem 35 air because of the introduction of nitrogen which perature of MOO-1200" F. and by using a proper is a di?icult substance to remove. However, it it catalyst such as that disclosed in the Kearby ap is desired to supply oxygen to aid in the regen plication previously mentioned, 1. e., a catalyst eration in chamber 2, same is preferably supplied containing about 79 parts by weight of'mag in relatively pure form or intermixed with a nesium oxide, about 20 parts by weight of F6203, 40 minimum amount of nitrogen. . about 5 parts by weight of C110, and about 1% In Fig. 11, I have shown a modi?cation in which parts by weight of K20 present in the conversion catalyst may be withdrawn by gravity through chamber in the form of a powder having a parti a standpipe 29, mixed with steam in an injector cle size of from 200-400 mesh to form within _22 to form a suspension disposed in the bottom the said chamber a dense phase suspension hav 45 of the standpipe 29, the steam entering through ing a weight of about 10—20 lbs. per cu. ft., the pipe 2|, and the suspension then discharged into butenes present in the feed stock, particularly the bottom of regenerator 2. The rate of ?ow of the butene-2, undergo dehydrogenation to form catalyst in standpipe 29 is controlled by a slide butadiene. The reactant. is added by dilution valve 23 or any other suitable means. Supple with steam and consequently the entering gas mental steam may be discharged through the preferably contains 4-20 volumes of steam per bottom of regenerator through line '32. The hy volume of hydrocarbon, and this mixture of drocarbon feed stock may be introduced as in the steam and catalyst forms the suspension having previous modi?cation through line 21, together the density indicated previously under best op with steam added through line ,28. Gas such erating conditions. The linear velocity oi! the as steam is discharged through pipes 3| into pipe gases in the'converslon chamber is such that the 29 to ?uidize the catalyst therein. The manner catalyst tends to gravitate slowly downward of operating the modi?cation shown inFig. II through the foraminous member 3 into the re generation chamber 2, while the‘ gaseous. reactant product proceeds upwardly into ‘disengaging chamber 4. It the linear velocities of the gas within the chamber I are from 1/2-3 ft. per sec ond, catalyst will settle out by gravity as indi cated but, nevertheless, it will be in a highly is otherwise the same as that shown in the 'modi ?cation of Fig. I. 60 ' ‘ In butene dehydrogenation there is or course an absorption of heat due‘ to the nature of the reaction. In order to compensate for the heat of reaction, preheated steam at a temperature of approximately 1300° F. is employed, or the ?uidized state, that is to say, it will not be com 65 catalyst may be heated by heat exchange while pacted but rather it will be in an ebullient state passing through line 29 in communication with of motion resembling somewhat a boiling liquid, a heating device 2, diagrammatically shown. and although the general direction of the cata (See Fig. I)._ When oxygen is introduced into lyst will be downwardly there will be a multi the regeneration chamber, the heat lost in con plicity of cross currents and upwardly directed 70 1/ version chamber 1 may be compensated for by currents having a dense phase level in about the means of the heat generated in the regeneration region of L. Above L, however, due to the ex chamber. 2 at least in a large degree, and there- panded cross-sectional ‘area 0! disengaging fore the hot regenerated catalyst is withdrawn chamber 4, the velocity of the up?owing vapors from regeneration chamber 2 and without op will be greatly reduced so that further settling 75 portunity substantially to cool, it is returned to K 2,411,592 pose more than one heat exchanger or other heating means for heating the regenerated cat alyst to higher temperatures. This has the ad vantage that the feed stock entering through line 21 need not be heated to as high a temperature the conversion chamber, thus transferring heat from the regeneration chamber to the conversion . chamber. While I have described my invention in detail with reference to butene dehydrogenation, it is to as would be necessary where the catalyst is not , be understood that the process and apparatus are equally applicable to the cracking of a gas oil, to externally heated in the manner indicated. A further modi?cation of my invention falls within the reforming of naphthaa-to the polymeriza the scope of cooling a portion of the regenerated tion of ole?ns and to numerous other hydrocar bon reactions ‘wherein hydrocarbon vapors are 10 catalyst‘ and discharging it into the region of the conversion chamber just above L or in the dis treated with a catalyst in powdered form under engaging chamber 4 where it serves to quench conditions such that the conversion results in the reaction products to temperatures below that the deposition of combustible material on the cat at which decomposition may occur. Thus the alyst. , ' I consider one of the main advantages of my 16 catalyst may be cooled to a temperature of say 300-500° F. and discharged in quantityinto the invention to be that in the case of butene de reaction products from which the catalyst ab hydrogenation which is carried out at tempera stracts heat and insures against losses by decom tures around 1200"’ F., that preheating above position or the butadiene, if that isthe product this temperature before discharge into the re ‘ action zone is avoided since heat is available in 20 being manufactured. I am aware that prior to my invention ?uid the conversion zone from the reaction taking catalyst processes were known and used by others, place ‘in the regeneration chamber. When a and I do not claim such operation of any appa~ butene is preheated above 1200° F. there is danger ratus therefor broadly. of thermal degradation with consequent loss in What I claim is: yields. In the normal operation, due to the endo 25 1. The combination in a ?uid catalyst appa thermic nature of the reaction, the feed stock is usually heated above reaction temperatures to . ratus comprising a conversion chamber and a re generation chamber contiguously and*~vertically compensate for the heat lost during the endo disposed, a foraminous member interposed be thermic reaction of dehydrogenation. As indi cated, this dangerous heating above reaction tem-' 30 tween said chambers, a disengaging chamber dis posed immediately above said conversion cham peratures is obviated in my process. Another ad ber, the disengaging chamber being of, an inter vantage of my invention is that because it is un nal diameter greater than the said’ conversion necessary to preheat above reaction tempera chamber, feeding means for withdrawing pow tures, it is not necessary to use expensive alloys which must be used'when very high temperatures 35 dered material from the bottom'of the regenera tion chamber, and conduit means adapted to'con are employed. In the dehydrogenation of butene, vey powdered material in the form of a suspen according to my process, for the reasons given, the sion to the conversion chamber, all substantially _ feed stock entering at 21 will not be heated above as set forth. , reaction temperatures. or course, among the 2. In combination, a vertical elongated zone of advantages of my improved apparatus is the 40 restricted cross-sectional area, a foraminous maintenance of continuity of operation in a, single member disposed in the said‘ elongated zone unit or reactor, whereas in the ?xed bed type or forming two chambers within said zone, a dis operation it will obviously be necessary to use a. engaging chamber superimposed on the upper plurality of reactors to maintain overall con tinuity of operation since in that type of opera 45 end of said elongated zone, said disengaging chamber being of greater cross-sectional area tion it is necessary to discontinue the reaction to regenerate the catalyst. This plurality of re than the ?rst-named zone, a standpipe in com actors greatly complicates and increases the nec munication with the uppermost of ‘said chambers, adapted to withdraw powdered material by grav essary equipment, requiring among other things complicated manifolding systems and automatic valves, both of which are apt at any time to get out of working order. '7 60 ity therefrom, a gas-solid mixing means disposed at the lower end of said standpipe, conduit means ‘ extending into said mixing means adapted to convey a gas into said last-named means where; Another advantage ‘of my processis that in a ?xed bed type of operation a large part of the by solid material therein may be dispersed in said cost of catalyst preparation lies in forming the 55 gas, and conduit means connecting the said mix catalyst into pills. In my operation, the catalyst ing means with the bottom of the lowermost said chambers , whereby a suspension may be dis is simply a powder and does not have to be pilled. A further advantage of my invention is that in _ charged, into said bottom of said lowermost chamber. ?xed bed units the contact time between gas and 3. The combination of a ?uid catalyst appa catalyst in'the reaction zone must be very short, 60 ratus comprising a vertical, elongated, substan , say of the order of 0.3 second, in order to prevent tially cylindrical shell type vessel, a foraminous degradation of the butadiene formed. This member interposed at substantially the mid short contact time requires high temperatures in vertical point of said vessel, the foraminous order to get the desired conversion, and of course it is the high temperature which causes the degra 65 member forming a demarcation between an up per conversion chamber and a lower regeneration dation of the product. In my apparatus I may chamber, a disengaging chamber superimposed operate at considerably lower temperatures and on said conversion chamber, the said disengag may therefore extend the contact time to '10 sec ing chamber being of greater cross-sectional area onds, which means that I may operate at around 1000° F. as compared with the 1200° F. tempera 70 than said cylindrical vessel, means for causing ture commonly employed in the ?xed bed type of outside circulation of powdered material contin- , operation. uously between said conversion and regeneration _ ' Numerous modi?cations of my invention may chambers, means for supplying a reactant to a be made without departing from the spirit there point at the lower end of the conversion cham of. For example, in line 25 (Fig. I), I may dis 76 ber, conduit means for supplying regeneration 9,411,893 > gas to the lowermost point at the bottom of said regeneration chamber, and means disposed at the ' upper portion of said disengaging chamber for withdrawing gaseous material. 4. The apparatus set forth in claim 3,-in which ber a ?uidized powdered catalyst material, caus ing the powdered material to gravitate through the means for circulating powdered material be the gas in the conversion chamber to permit said a foraminous member into a regeneration cham ber contiguously disposed immediately below said conversion chamber by regulating the velocity of tween the said chambers comprises a solid feed ing means disposed at the lower end of said re gravitation, contacting the catalyst in the re generation chamber with steam whereby con-' generation chamber adapted to withdraw pow taminants thereon are consumed and catalyst is dered material therefrom, an injection means l0 revivi?ed, withdrawing revivitied catalyst from adapted to form a suspension of said powdered the bottom'of said regeneration zone, and recy material and a gasiform material, and conduit means adapted to convey the suspension formed in the injection means to the conversion cham cling it substantially uncooled to a point near the top of said conversion zone. her. 5. 'Ihe apparatus set forth in claim 3, in which the means for causing circulation of powdered material between the conversion chamber and the regeneration chamber comprises a standplpe preheated oleflns into a vertically disposed con version chamber of restricted cross-sectional area, simultaneously discharging into said cham 7. In the catalytic dehydrogenation of olefins, the improvement which comprises discharging ' ber a ?uidized powdered catalyst material, caus whose upper end is in communication with the 20 mg the/powdered material to gravitate through upper portion of the conversion chamber and a foraminous member into a regeneration cham whose lower end is in communication with an in ber contiguously disposed immediately below- said Jection means, means for injecting a gaseous me conversion chamber by regulating the velocity of dium into said injection means to form ‘a sus the gas in the conversion chamber to permit said pension, and conduit means -for conducting the 25 gravitation, contacting the catalyst in the re suspension formed ‘in the injection means into generation chamber, with steam whereby contam the lower portion of the regeneration chamber; inants thereon are consumed and catalyst is re 6. In the catalytic dehydrogenation of butenes, the improvement which comprises discharging preheated butenes into a vertically disposed con version chamber of restricted cross-sectional area, simultaneously discharging into said cham vivi?ed, withdrawing revivi?ed catalyst from the bottom of said regeneration zone, and recycling 30 it substantially uncooled to a point near the top of said conversion zone. ' EDWARD D. REEVES.