US2913403A - Non-regenerative fluid hydroforming with a platinum containing catalyst - Google Patents

Description

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Nov. 17, 1959 w. A. REX ETAL 2,913,403

NON-REGENERATIVE FLUID HYDROFORMING WITH A PLATINUM CONTAINING CATALYST Filed Aug. 25, 1955 2 Sheets-Sheet 1 2I CATALYST SUPPLY 2OG v I 40 f4I -40 x I 1 L :-I9a COOLER XZZQ... f 22 REACTOR-- I-- SEFLAEATORZ I8 6 -D T g I TO T PURIFICATION FEED OIL FIG.-l

B 9,. I M Attorney Fev. 17, 1959 w. A. REX ETAL 2,913,403

NON-REGENERATIVE FLUID HYDROF'ORMING WITH A PLATINUM CONTAINING CATALYST Filed Aug. 25, 1955 2 Sheets-Sheet 2 FIG.'2

Virginia C. Rex, Adminisfrafrix for estate of Walter A. Rex, Deceased CharlgE. Hem Inger By Attorney rgroup metal is an example. cerned with the isomerization and dehydrogenation of cyclo-pentane types of naphthenes to aromatics and the dehydrogenation of hexane types of naphthenes to arolytic dehydrogenation of naphthene-containing naphtha to high octane number motor fuels using a fluidized catalyst adapted to reform naphthas, of which a platinum The invention also is con matics without substantial conversion (i.e. cracking) of (the non-naphthenic constituents of the naphtha.

The type of process herein described and claimed is generally called hydroforming and is defined as a process in which naphthene-containing naphthas are contacted :at elevated temperatures and pressures with a solid catalyst in the presence of added hydrogen, and 1s further characterized in that there is no net consumption of hydrogen. Usually there is a net production of hydrogen. The process is usually applied to virgin naphthas containing substantial amounts of cycloparaffins, such as methyl cyclohexane to yield the corresponding aromatic hydrocarbon by dehydrogenation. Extensive isomerization usually occurs involving a rearrangement of the car: bon atoms in a ring and/or straight chain compound.

Heretofore and prior to the present invention it was old to carry out the dehydrogenation of naphthenic naphthas in the presence of added hydrogen-containing gas over a platinum-containing catalyst in fixed catalyst bed reactors, the hydrogen serving the purpose of preventing or retarding the deactivation of the catalyst by carbon or coke deposition thereon. It has been necessary to prevent such deactivation to operate at pressures in the order of 750 psi. and to employ recycle rates of hydrogencontaining gas upwardly of 5,000 standard cubic feet per barrel of feed. The high pressure employed in this type of operation has caused undesirable cracking of the paraf fins present in the feed stock, resulting in the production of low quality hydrocarbons. In addition, the highly endothermic nature of the dehydrogenation reaction causes substantial temperature drops in the adiabatic fixed catalyst bed reactors. To counteract the decreased activity of the catalyst at the low temperatures prevailing at points removed from the inlet to the adiabatic reactors, the practice has been to use a multiplicity of reactors operating in series with reheating by means of furnaces of the eflluent from a reactor before charging the effluent to the next reactor in the series.

The main object of the present invention is to provide a process wherein the desired dehydrogenation reactions (e.g. hydroforming and other reactions mentioned previously) are carried out in a single isothermic reactor, that is one in which the temperature in all parts of the reactor is substantially the same.

A second object of this invention is to obtain the desired dehydrogenation reactions in the presence of recycled hydrogen-containing gas, at pressures below those currently used.

A third object of this invention is to process typical virgin naphthas under conditions which will give high yields of products having clear research octane numbers United States Patent estates Patented Nov. 17 1959 ice above 85 C.F.R.R. in a continuous process, without undue formation of butane and lighter hydrocarbons.

A further object of this invention is to obtain a maximum yield of benzene from cyclohexane and methyl cyclopentane, or toluene from ethyl cyclope'ntane or methyl cyclohexane.

Another object of this invention is to provide a means of adding heat directly to the reactor Without the use of large extraneous naphtha and hydrogen-containing gas heating furnaces.

Other and further objects of the invention will be ap* parent in the more detailed description and claims which follow.

To the accomplishment of the foregoing and related ends, the present invention provides a process characterized in that in a single vessel, a fluidized bed of finely divided catalyst containing a platinum group metal or equivalent is formed, and the process is so operated that the amount of carbon normally laid down on the catalyst is greatly reduced and in practical eifect is virtually avoided. This is true even though the hydroforming operation is conducted at pressures very substantially below those employed in current conventional processes at similar levels of treating severity. To obtain high yields of high octane product, the conventional hydroforming operation carried out in fixed beds using catalyst in the form of pills or the like resulted in inordinately large deposits of carbon on the catalyst unless the pressures in the reaction zone were of the order of 750 psi. or higher. Due to the fact, however, that the catalyst employed in the present process is finely divided, carbonaceous deposits on the catalyst is at least retarded or even completely eliminated due to the fact that the small size of each individual particle of catalyst provides a large surface area which is available for contact with the hydrogen, which hydrogen prevents carbon formation or removes it if formed.

Another important feature of the present process is that the thorough mixing of the catalyst due to its state of being in a dense turbulent fluidized bed serves to equalize temperature conditions throughout the bed thus preventing local hot spots, concomitant with cracking of the feed, particularly,the cycloparaffins contained therein, thus avoiding or at least greatly retarding carbon deposition on the catalyst.

Another accomplishment of the present invention relates to the method of supplying at least a portion of the heat required to support the endothermic reaction of hydroforming naphthenic naphthas and the like. This involves withdrawing catalyst from the reactor in the form of fluidized stream and conducting it into a suitable heating zone such as a furnace in the form of an aerated column where it is heated by heat exchange with a hot gaseous fuel or the like. In this reheating of the catalyst the same is withdrawn from the reactor at a temperature of, say, 900 F. and heated in the said heating means to a temperature of around 1000 F. and then returned to the reactor. This feature of the invention eifects important economies, for in the prior practice the heat was carried into the reactor by the heated recycled hydrogencontaining gas and the preheated oil feed. Since these recycled gases, as recovered from the purification system are ordinarily at a relatively low temperature, reheating these gases from a temperature of around F. to 1000? F. requires much more heat energy to introduce a given quantity into the reactor than is required when heating the withdrawn catalyst from 900 F. to 1000 F. for the same purpose.

Another important feature of the present invention resides inthe manner in which the oil feed and the recycled hydrogen gas are heated and thereafter introduced intothe reaction zone. The oil and the said hydrogencontaining gas are separately preheated outside the reactor and are not mixed prior to introduction into the reactor. This latter feature has the important advantage that since the hydrogen-containing gas is at a much higher temperature than the preheated oil as these substances enter the reactor, the preheated oil is not subjected to thermal cracking temperatures outside the reactor. Inside the reactor the superheat content of the hydrogen is utilized to support the endothermic reactions therein occurring.

In the accompanying drawings there are depicted in Fig. I a simplified flow plan showing apparatus in which a preferred modification of the present invention may be carried into effect; and in Fig. II, there is shown a modification which includes means for adding additional heat to the hydroforming reactor.

Similar reference characters refer to similar parts throughout the views.

Referring to Fig. I in detail, 1 represents a reactor containing a bed C of dense fluidized turbulent powdered catalyst, the active component of which catalyst is a platinum group metal, such as platinum itself, carried on a suitable support such as active alumina. A typical catalyst composition would be as follows, 99.0 wt. percent Al O 0.5 wt. percent platinum, and 0.5 wt. percent of hydrogen fluoride. The catalyst may contain silica in a minor amount. The support may or may not possess high surface area. It will be understood that these proportions may be varied so that the platinum content of the catalyst may be from 0.051.0 wt. percent of the total catalyst. In case where palladium is used in place of platinum, a substantially larger amount of this material is usually required, say, from 0.5-3.0 wt. percent of total catalyst. The presence of hydrogen fluoride in the catalyst is optional.

Other catalysts which may be used include V Group metal oxides such as, for example, V A good catalyst in this latter category would be one containing the following ingredients in percentages by weight: V 0 340%, K as K 0 1%, and A1 0 balance. The A1 0 may be mixed with SiO and may form a carrier of diminished cracking activity when the carrier has a low surface area.

Referring again to the fluidized bed of catalyst as shown in the drawing, the same extends in the form of a bed from a grid G to an upper dense phase L, and above L there is a light dispersion or phase of catalyst in gasiform material. In operation, recycle hydrogen-containing gas recovered from the crude product is withdrawn from a separator S via line 10, then passed through compressor 11 into line 12 from which it is charged to a furnace 13, heated in coil 14, withdrawn and charged via 15 into the bottom of the reactor 1. As indicated in the drawing the reactor itself is in the general form of a vertical cylinder with a convex crown and a conical bottom section. The hydrogen gas enters the bottom of the reactor, passes upwardly through grid G and into the fluidized bed C of catalyst. It is, of course, the superficial velocity of the gas and/or vapors and the particle size of the catalyst which maintains the bed of catalyst in the mentioned fluidized state. This is accomplished by regulating the superficial velocity of these gasiform materials so that they lie within the range of about 0.1-1 ft. per second measured at operating conditions, preferably, in the range of 0.2-0.5 ft. per second when the catalyst has an average particle size of from about 200-400 mesh 0 finer.

The oil to be treated which would ordinarily be a virgin naphtha containing from 30-45% of naphthenes is introduced in the present system through line 16, is thereafter heated in coil 17 in furnace 13 to a temperature of around 950 F. thereafter withdrawn from the furnace 13 through line 18 and charged into the bed of catalyst above the grid G, but in relatively close proximity thereto.

Under conditions more fully set forth hereinafter, the

desired conversion takes place, the principal chemical reaction being one in which naphthenes are dehydrogenated to the corresponding aromatic as where methyl cyclohexane is dehydrogenated to form toluene. It will be understood, of course, that secondary reactions may take place, as where ethyl cyclopentane is first isomerized to form methyl cyclohexane which latter component then undergoes dehydrogenation to form toluene. Any olefins that are formed are hydrogenated so that the product finally withdrawn from the reactor consists almost entirely of aromatics and paraflins. The crude product emerges from a dense phase, passes through a light phase above L in reactor 1, and in this region entrained catalyst tends to separate by gravity from the gasiform material and gravitate toward the dense phase bed. However, some catalyst fines persist in the gasiform material and to remove these fines, the gasiform product is forced through two or more filters 19 and 19a in which the last trace of catalyst is substantially completely removed from the vapors. The vapors and gases emerge from the reactor through either branch line 20a or 20b, and after passing through a 4-way valve V, thence pass via line 21, to a cooler 22 wherein the normally liquid constituents are condensed and thereafter charged via line 23 into a separator S. The crude product is withdrawn from separator S via line 24 and delivered to product purification in equipment not shown while the hydrogencontaining gas is recovered via line 10, as indicated above.

Referring to the filters 19 and 19a disposed as shown in the upper part of reactor 1, these are conventional devices and constructed from a material having adequate mechanical strength, and at the same time possessing the capability of gas permeability. For increased surface for a given weight, they are often shaped, as indicated in the drawing, in the form of thimbles.

In Fig. I, these filters which are removably integral with a header 40, are disposed in the top of reactor 1, as shown. In operation, the efliuent hydrocarbon vapors pass through, say, the filter 19 and catalyst fines are removed. These vapors pass from the filter 19 to the left of a vertical dividing plate or baffle 41, and flow from the reactor through line 20a, 4-way valve V and thence to purification in the manner previously indicated.

Meanwhile, filter 19a is blown with recycle gas from line 120 in communication with 4-way valve V, which is manipulated to permit flow of this gas through line 20b into the reactor and downwardly therein through the filter 19a to blow out catalyst acquired during a previously filtering period.

Filter 19 may then be taken ofi the on-stream phase and by manipulation of valve V, recycled hydrogen gas from line 20a passed through it to clean the said filter. Meanwhile, of course, filter 19a is returned to the onstream phase.

The drawing shows only two filters, but more than two may be employed so that, say, three could be always on-stream while a fourth is undergoing catalyst removal.

Although less preferred, cyclone separators may be employed in lieu of the filters 19 and 1911. In the case where cyclone separators are employed, the separation of solids from the efliuent vapors may not be complete, and therefore, it is necessary to scrub the vapors issuing from the reactor with, say, an oil to form a slurry which is returned to the reactor.

In Fig. II there is shown a modification of the reactor 1 depicted in Fig. I. In the lower section separated from the reactor section by a plate 50 of an enlarged reactor 1, there is disposed a fluidized bed of solids C and imbedded in this fluidized bed of solids is a plurality of hairpin tubes 1 Whose upper open ends are in communication with the fluidized bed of catalyst C in the upper section of the reactor. The fluidized bed of solids C which may be finely ground inert material, such as powdered rock, slate, finely ground sand, etc., is heated by hot gases which enter the bottom section. These hot fumes or gases may be formed in afurnace F to which air is fed from line 31-and a gaseous fuel from line 32. The gaseous fuel is burned in F and withdrawn through line 33, and introduced into the bottom section of reactor 1. The fumes pass upwardly through a supporting grid of screen G into contact with the fluidized bed of inert solids C and the superficial velocity is controlled as usual so as to form the fluidized bed of powdered solids into a dense fluidized mass. The fumes are withdrawn through a pipe 51. Catalyst from bed C descends in one leg of the hairpin tubes f, passes in heat exchange relationship with the hot bed of fluidized inert powdered material C which may acquire a temperature of 1200- 1500 F., and then passes upwardly through the other leg of hairpin tubes f. To aid the flow of catalyst in the manner indicated, a portion of the recycled hydrogen gas in line 12 is passed from line 12 into branched line 12a, 12b, etc. into the return leg of the hairpin tubes f at a point above their lower ends. Thus, in the case where it is necessary to supply additional heat to the bed of catalyst C and to the reaction zone in which it is contained over and above that supplied by the preheat furnace 13, the catalyst may be heated in a manner which is now described in the arrangement of apparatus shown in Fig. II.

To summarize at this point briefly, the present invention is based on the principle that naphthas may successfully be reformed in a fluidized catalyst system in a continuous manner. The process normally operates so as not to require catalyst regeneration, because the finely divided state of the catalyst and the thorough mixing of hydrogen gas and catalyst tends to prevent build-up of carbonaceous deposits on the catalyst. Also, the fluidized state of the bed creates isothermal conditions, thus avoidinglo'cal hot spots which latter cause cracking and coke formation. However, say, after operation of a week or two, the octane rating of the product may decline, whereupon catalyst regeneration with hydrogen or air may be indicated. In order further to explain the present invention, there is set forth below a specific example illustrating a preferred modification of the invention with the understanding that the conditions set forth as well as the results are merely illustrative of the invention and to not impose any limitation thereon.

EXAMPLE An East Texas naphtha may be processed in the presence of a catalyst containing 0.4 wt. percent platinum, 0.6 wt. percent HF and 99 wt. percent A1 in the manner hereinafter set forth. The feed stock had the following inspection:

This feed may be subjected to the following operating conditions:

Operating Conditions Preferred Range Pressures, p.s.i 400 200-500 Temperature, F 910 850-960 Space Velocity, w./hr./w 2.0 0. 7-4. 0 Recycle gas, c.f./bbl. feed (standard conditrons) 3, 500 2, 000-7, 500 Purityoi recycled hydrogen 85-90 60-90 Naphtha feed temperature, 975 950-1, 025 Recycle gas temperature, F 1,100 1, 000-1, 300 Reheated catalyst temp, Fr 1, 000 950-1, 000

Typical results of the foregoing process on the illustrative feed mentioned in this example are as follows:

The amount of platinum suitable for use as a catalyst in the present invention may vary from a relatively low value, such as 0.05 to an upper limit of about 1%. Instead of platinum, palladium may be used in the catalyst composition, but the amount of palladium required is usually about three times the platinum requirement. Similarly, the amount of HF may vary from 0.1. to 1% of the total catalyst composition. The use of hydrogen fluoride is, as stated, optional. Furthermore, in orderto stabilize the catalyst, the alumina may be mixed or compounded with a relatively minor amount of SiO say, so as to provide 10-15% SiO of the total catalyst composition.

To recapitulate briefly, the present invention relates to a method of carrying out a hydrocarbon synthesis operation under substantially isothermal conditions, relatively loW pressures in a continuous operation, and last but not least, providing means for adding heat to the reaction zone under conditions such that the use of large naphtha and recycle gas furnaces are avoided. In this latter connection, it is pointed out that the present method of heating the catalyst in which the catalyst contacts hydrogen at temperatures substantially higher than those prevailing in the reaction zone atfer a relatively short residence time in said reaction zone tends to purify the catalyst, as well as to heat it by hydrogenating to volatile material on the carbonaceous deposits which are formed on the catalyst during the hydroforming phase. According to the present invention, the catalyst at no time contacts or is associated with the oxides of carbon at any time, including residence time of the catalyst during hydroforming in the reaction zone, for it has been found that the presence of the oxides of carbon in the reaction zone during hydroforming adversely affects the catalyst to a serious degree as is evidenced by the below experiments.

Experiment I A reforming operation was conducted in an isothermal reactor containing a catalyst comprising 0.6 weight percent of platinum supported on alumina employing a 200 to 300 F. boiling range virgin naphtha of 51 research octane number. The naphtha feed stock was charged to the reactor together with 2500 cubic feet of pure hydrogen per barrel of feed stock under reaction conditions including a temperature of 900 F., a pressure of 225 p.s.i.g. and a space velocity of 2 volumes of feed per volume of catalyst per hour. Reforming operations were conducted for a period of about 130 hours during which time a product was obtained having about an 85 to 87 research octane number.

At the end of ths time carbonaceous deposits were removed from the catalyst by burning. The catalyst was then purged with nitrogen and cooled to 300 F. After the nitrogen purge the catalyst was heated preparatory to reforming operations to a temperature of about 800 F. while passing therethrough a gas containing 73 volume percent hydrogen, 8 volume percent carbon dioxide, 1 'volume percent nitrogen and 1 volume percent carbon 7 monoxide, and 17 volume percent light olefins and paraffins.

After the temperature reached 800 F. the feed stock was again brought into contact with the catalyst at a pressure of 225 p.s.i. g. at a velocity of 2 v./ v./ hr. together with the gas containing 8 volume percent of carbon dioxide and 73 volume percent of hydrogen and the catalyst was brought to a temperature of 900 F. The research octane number of the product was initially 69 and after 20 hours of operation had declined to 65. Pure hydrogen was then substituted for the said gas which contained both hydrogen and carbon dioxide but the octane number of the product continued to decline until a product having a research octane number of about 60 was obtained after about 10 hours.

At this point reforming operations were discontinued and carbonaceous deposits were removed from the catalyst by burning to reactivate the catalyst. At the end of this time the catalyst was cooled and purged with nitrogen. Reiorming operations were recommended under the first stated reaction conditions. The product had a research octane number of about 85 to 87.

The gas containing 8 volume percent of carbon dioxide and 73 volume percent of hydrogen was substituted for the pure hydrogen while maintaining other conditions constant. The research octane number of the product again declined to a value of less than 60 within 6 hours.

Experiment II A reforming operation was conducted in an isothermal reactor containing a catalyst comprising 0.6 weight percent of platinum supported on alumina employing a 200 to 300 boiling range virgin naphtha of 51 research octane number. The naphtha was charged to the reactor together with 2500 cubic feet of hydrogen per barrel of feed stock under reaction conditions including a temperature of 900 F., pressure of 225 p.s.i.g. and a space velocity of 2 volumes of feed per volume of catalyst per hour. Reforming operations were conducted for a period of about 80 hours during which time a product was obtained having about an 85 to 87 research octane number.

At the end of this time the flow of feed stock to the catalyst was discontinued while continuing the charge of hydrogen at the indicated temperature and pressure. The hydrogen was replaced with flowing nitrogen while still maintaining the indicated temperature and pressure. Next, a gaseous mixture consisting of about 10 volume percent of carbon dioxide, 10 volume percent of hydrogen and 80 volume percent of nitrogen was charged to the catalyst for about 3 hours. The exist gas was analyzed and found to contain about 4 to 5 volume percent of carbon monoxide. At the end of this time reforming operations were resumed under the above described operating conditions. A product was obtained having a research octane number of about 73 to 74.

Numerous modifications of the present invention may be made by those who are skilled in the present art with out departing from the spirit thereof.

What is claimed is:

l. The method of hydroforming a hydrocarbon oil containing naphthenes which comprises providing a dense, turbulent fluidized bed of a platinum-containing catalyst by upward streams of hydrogen gas in a hydroforming zone, charging said oil to said zone in a preheated state, maintaining a pressure of from 100500 p.s.i. and a temperature of from about 850-950 F. in said hydroforming zone, simultaneously charging to said zone but unmixed with said oil prior to introduction into the hydroforming zone, from LOCO-7,000 standard cubic feet of hydrogen-containing gas per barrel of oil fed to said hydroforming zone, said hydrogen-containing gas being at an inlet temperature of from about l0001300 F., passing said oil and vapors upwardly through said fluidized bed at a velocity of. from about 0.1 to 1 foot per sec- 0nd, thereby-maintaining the catalyst in the bed in a highly turbulent state to minimize local overheating and carbon formation, withdrawing a portion of said fluidized catalyst continuously from said zone in the form of a plurality of confined streams, heating said withdrawn catalyst out of contact with the oxides of carbon by indirect heat exchange with a separate fluidized bed of hot solids having a temperature substantially higher than about 1000 F., said hot solids being disposed in a heating zone directly below said hydroforming zone and both zones being disposed within the same generally confined space, returning said heated catalyst directly to said hydroforming zone to supply heat to the hydroforming reaction, permitting the said hydrocarbon oil to remain resident in contact with the catalyst in the hydroforming zone for a sufficient period of time to effect the desired conversion, and recovering from said hydroforming zone a. hydroformed product.

2. The method according to claim 1 in which a stream of catalyst undergoing said heating by indirect heat exchange is withdrawn downwardly by gravity from the fluid bed in the hydroforming zone and is then, after said heating, returned upwardly into said fluid bed with the aid of recycled hydrogen.

3. In a process of hydroforming a hydrocarbon naphtha containing naphthenes supplied to a dense fluidized bedof platinum-containing catalyst at a pressure of 100 to .500 p.s.i. and a temperature of from about 0-9S0 F. with hydrogen in a hydroforming zone, the improvement which comprises withdrawing a portion of said catalyst continuously downwardly from said hydroforrning zone in the form of a plurality of confined vertical streams, heating the streams of withdrawn catalyst out of contact with oxides of carbon by indirect heat exchange with a separate fluidized bed of hot solids having a temperature substantially higher than about -3 F., said hot solids being in a separate heating zone directly below said bydroforming zone, said zones and streams being confined within the same general enclosed space, returning the heated catalyst in a plurality of confined vertical streams aided by the upward flow of hydrogen gas to supply heat to the hydroforrning zone where said gas becomes admixed with the naphtha, said confined downward streams and confined upward streams having a hairpin shape, including a U-bend at their lower ends within said fluidized bed of hot solids.

4. In a process of hydroforming a naphthene-containing naphtha hydrocarbon oil passed as vapor at 850-95 0 F. up through a bed of fluidized platinum-containing catalyst in a hydroforming zone, the improvement which comprises continuously withdrawing a portion of the catalyst from the said bed in a stream confined in a heat exchange tube that descends into a fluidized bed of hot solids in a heating zone directly below a bottom entrance of the naphtha vapor to said hydroforming zone then returns the stream of catalyst upwardly in its return circuit into the fluidized bed contained in the hydroforming zone, said zones and tube having a common heat enclosure, heating the stream of withdrawn and returned catalyst by indirect heat exchange with fluidized hot solids in the heating zone surrounding a lower part of the heat exchange tube, and aiding the flow of the stream of catalyst being returned upwardly by passing hydrogen gas into the heat exchange tube at a point above its lower end.

References Cited in the file of this patent UNITED STATES PATENTS 2,459,836 Murphree Jan. 25, 1949 2,643,214 Hartwig June 23, 1953 2,656,304 McPherson et al Oct. 20, 1953 2,692,847 Rex Oct. 26, 1954 2,694,672 MacLaren Nov. 16, 1954 M ve.

Claims (1)

1. ATHE METHOD OF HYDROFORMING A HYDROCARBON OIL CONTAINING NAPHTHENESE WHICH COMPRISES PROVIDING A DENSE, TURBULENT FLUIDIZED BED OF A PLANTINUM-CONTAINING CATALYST BY UPWARD STREAMS OF HYDROGEN GAS IN A HYDROFORMING ZONE, CHARGING SAID OIL TO SAID ZONE IN A PREHEATED STATE, MAINTAINING A PRESSURE OF FROM 100-500 P.S.I. AND A TEMPERATURE OF FROM ABOUT 750*-950*F. IN SAID HYDROFORMING ZONE, SIMULTANEOUSLY CHARGING TO SAID ZONE BUT UNMIXED WITH SAID OIL PRIOR TO INTRODUCTION INTO THE HYDROFORMING ZONE, FROM 2,000-7000 STANDARD CUBIC FEET OF HYDROGEN-CONTAINING GAS PER BARREL OF OIL FED TO SAID HYDROFORMING ZONE, SAID HYDROGEN-CONTAINING GAS BEING AT AN INLET TEMPERATURE OF FROM ABOUT 1000-*1300*F., PASSING SAID OIL AND VAPORS UPWARDLY THROUGH SAID FLUIDIZED BED AT A VELOCITY OF FROM ABOUT 0.1 TO 1 FOOT PER SECOND, THEREBY MAINTAINING THE CATALYST IN THE BED IN A HIGHLY TURBULENT STATE TO MINIMIZE LOCAL OVERHEATING AND CARBON FORMATION, WITHDRAWING A PORTION OF SAID FLUIDIZED CATALYST CONTINUOUSLY FROM SAID ZONE IN THE FORM OF A PLURALITY OF CONTACT STREAMS, HEATING SAID WITHWRAWN CATALYST OUT OF CONTACT WITH THE OXIDES OF CARBON BU INDIRECT HEAT EXCHANGE WITH SEPARATE FLUIDIZED BED OF HOT SOLIDS HAVING A TEMPERATURE SUBSTANTIALLY HIGHER THAN ABOUT 1000*F., SAID HOT SOLIDS BEING DISPOSED IN A HEATING ZONE DIRECTLY BELOW SAID HYDROFORMING ZONE AND BOTH ZONES BEING DISPOSED WITHIN THE SAME GENERALLY CONFINED SPACE, RETURNING SAID WITHIN THE SAME GENERALLY CONFINED SPACE, RETURING SAID PLY HEAT TO THE HYDROFORMING REACTION, PERMITTING THE SAID HYDROCARBON OIL TO REMAIN RESIDENT IN CONTACT WITH THE CATALYST IN THE HYDROFORMING ZONE FOR A SUFFICIENT PERIOD OF TIME TO EFFECT THE DESIRED CONVERSION, AND RECOVERING FROM SAID HYDROFORMING ZONE A HYDROFORMED PRODUCT.

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