US3235485A - Hydrocracking-reforming process combination - Google Patents

Description

Feb. 15, 1966 N. KAY ETAL 3,235,485

HYDROCRACKING-REFORMING PROCESS COMBINATION 4 Sheets-Sheet 1 Filed June 25 NNR Feb. 15, 1966 N. KAY ETAL 3,235,485

HYDROCRACKING-REFORMING PROCESS COMBINATION Filed June 25, 1963 4 Sheets-Sheet 2 INVENTOR. Avn/0445 L 44)/ Feb. 15, 1966 N. L.. KAY ETAL 3,235,485

HYDROCRAGKING-REFORMING PROCESS COMBINATION Filed June 25, 1963 4 Sheets-Sheet 5 I NVENTORS Feb. l5, 1966 N. KAY ETAL 3,235,485

HYDROCRACKING-REFORMING PROCESS COMBINATION Filed June 25, 1965 4 Sheets-Sheet 4 FIG- 5 o 5505 4, +42 h o F5505 ,5; ,L52 /05 INVENTOR. /1//c//045 AMY may@ R556 United States Patent O 3,235,455 HYDROCRACKENG-REFRMHNG PROCESS CUMBINATIN Nicholas L. Kay, Fullerton, and Cloyd I. Reeg, Orange, Calif., assignors to Union @il Company of California,

Los Angeles, Calif., a corporation of California Filed lune 25, 1963, Ser. No. 290,366

4 Claims. (Cl. 20S- 60) This invention relates to catalytic hydrocracking, and more particularly is concerned with the manufacture of high-octane gasoline in maximum yields by the combination of hydrocracking followed by reforming of the hydrocrackate gasoline. The invention is concerned specifically with the provision of optimum hydrocracking conditions in Ithe hydrocracking-reforming combination, whereby maximum overall yields of gasoline at a given octane level are obtained, based upon fresh feed to the hydrocracker. Brieiiy, the principal novel features of the process comprise carrying out the hydrocracking operation at very low tempertaures of, e.g., 400-625 F., while maintaining in the hydrocracking zone certain minimum concentrations of hydrogen sulfide. It has been found that by hydrocracking at low temperatures in the presence of hydrogen sulfide, and then reforming the C7-I- hydrocrackate gasoline, significantly higher overall yields of C5| reformate gasoline plus C5-C5 hydrocrackate gasoline are obtained than can be obtained by reforming to the same octane level a C7-lhydrocrackate produced in the absence of hydrogen sulfide, or in `the presence of hydrogen sulfide at high hydrocracking temperatures.

ln a preferred aspect of the invention, two separate hydrocracking stages are employed, the first operating at relatively high temperatures in the presence of hydrogen sulfide and nitrogen compounds, and the second at relatively low temperatures in the absence of nitrogen compound but in the presence of hydrogen sulfide to complete the hydrocracking of unconverted oil from the first stage. The gasoline produced in each hydrocracking stage is then fractionated to recover a C7-400" F. hydrocrackate gasoline fraction which serves as feed to the reformer, and a C5-C6 light hydrocrackate gasoline fraction which is not reformed but is subsequently blended back with the reformate gasoline. ln a still further preferred aspect of the invention, the C7-400 F. hydrocrackate gasoline product is further fractionated into a relatively light fraction and a relatively heavy fraction, the former being reformed at relatively low temperatures and pressures, and the latter at relatively higher temperatures and pressures.

The principal object of `the invention is to increase gasoline yields at a given octane level over the yields which have previously been obtainable by the hydrocracking-reforming series combination. A more specific object is to provide novel hydrocracking conditions tailored to minimize hydrogen consumption, light gas production and coke formation, and to maximize C5-}- gasoline yields in the overall hydrocracking-reforming process combination. Other objects will be apparent from the more detailed description which follows.

The yield-octane values obtained in the hydrocrackingreforming combination are a resultant of a great many complex variables in each of `the two process steps. Ultimate liquid yields of gasoline generally depend upon the aromaticity of the final gasoline product, the proportion of feed which was hydrogenated and cracked to light gases in either the hydrocracker or the reformer, and the proportion of feed which was polymerized to high-boiling polymer in the reformer. Octane values depend primarily upon the proportion of aromatic hydrocarbons and branched-chain parafiin hydrocarbons in the final product, as well as upon the total content of cyclic hydrocarbons versus parafiins. The ratio of high-boiling to low-boiling components also has an effect upon octane values. The complex interrelation of these variables renders it very difficult to predict optimum process conditions in the hydrocracking-reforming combination.

We have now discovered that when the hydrocracking operation, or at least a portion thereof, is conducted at very low temperatures in the presence of hydrogen sulfide, a considerably improved yield-octane relationship is obtained from the overall combination, as compared to the results obtainable when the hydrocracking operation is carried out in the absence of hydrogen sulfide, or in the presence of hydrogen sulfide at high temperatures. This improvement is most apparent in the preferred mode of operation wherein only the Cq-lfraction of hydrocrackate gasoline is subjected to reforming, and the resultant C5-lreformate gasoline is then blended back with all or a portion of the C5-C6 fraction of hydrocrackate gasoline. In view of the complexities involved, we are unable to explain these results on completely satisfactory theoretical grounds. It would appear on its face however that low-temperature hydrocracking is probably conducive to minimizing the production of light gases, and the hydrogen sulfide appears to inhibit selectively the hydrogenation activity of the catalyst, thus avoiding complete hydrogenation of aromatics and minimizing the isomerization of isoparafiins to normal parafiins. It is almost certain however that other factors are operative in the process.

The improvements in liquid yield at a given octane level obtained by the process of this invention generally amount to between about 2% and 5%, as compared to either the sulfur-free hydrocracking system, or the high temperature system wherein hydrogen sulfide is present. Operative hydrocracking temperatures for obtaining these results generally lie between about 400 and 625 F., preferably between about 500 and 600 F. Effective hydrogen sulfide concentrations lie in the range above about 0.01 millimole thereof, and preferably above about 1 millimole, per mole of hydrogen in the hydrocracking zone. The hydrogen sulfide may be added as such to the recycle gas, or it may be produced in the hydrocracker by the decomposition of indigenous sulfur compounds in the feed, or added sulfur compounds. In a hydrocracking operation utilizing 10,000 s.c.f./b. of hydrogen, l millimole of hydrogen sulfide per mole of hydrogen corresponds to about 0.25 weight-percent of sulfur in a feedstock weighing 350 pounds per barrel.

To operate a hydrocracking process at the low temperatures required herein, and at practical conversion levels of about 40-80 volume percent conversion to C4-lgasoline per pass, and at reasonable space velocities of about 0.5 to 3, very active hydrocracking catalysts are required. It is also required that the feed to this low temperature hydrocracking step be essentially free of nitrogen, i.e., it must contain less than about 50 parts per million, and preferably less than about 2O parts per million of total nitrogen. Suitable hydrocracking catalysts comprise a minor proportion of a Group VIII metal hydrogenating component supported upon a highly acidic, high-surface-area cracking base having a Cat-A activity index of at least about 35. The preferred hydrogenating metals are the Group VIII noble metals, and particularly palladium, platinum or rhodium. The iron group metals, particularly nickel, may be used, but to less advantage. Suitable cracking bases may comprise coprecipitated silica-alumina, silica-magnesia, aluminaboria, silica-zirconia, silica-titania, silica-zirconia-titania, etc. Acidic metal phosphates such as aluminum phosphate may be employed. Any of the foregong cracking bases may be further promoted by the addition of a suitable halide such as HF, BF3 or SiF4. The preferred cracking bases comprise partially dehydrated, zeolitic, crystalline molecular sieves, eg., of the X or Y crystal types, having relatively uniform pore diameters of about 8-14 A., and comprising silica, alumina and one or more exchangeable cations.

A particularly active and useful class of molecular sieve cracking bases are those having a relatively high SiO2/Al203 ratio, eg., between about 2.5 and 10. The most active forms are those wherein the exchangeable zeolitic cations are hydrogen and/ or a divalent metal such as magnesium, calcium or zinc. In particular, the Y molecular sieves, wherein the SiO2/Al203 ratio is between about 4/1 and 6/ 1, are preferred, either in their hydrogen form, a divalent metal form, or a mixed divalent metal-hydrogen form. Normally, such molecular sieves are prepared first in the sodium or potassium form, and the monovalent metal is ion-exchanged out with a divalent metal, or where the hydrogen form is desired, with an ammonium salt followed by heating to decompose the zeolitic ammonium ion and leave a hydrogen ion. Molecular sieves of this nature are described more particularly in Belgian Patents Nos. 577,642, 598,- 582, 598,683 and 598,682.

As in the case of the X molecular sieves, the Y sieves also contain pores of relatively uniform diameter in the individual crystals. In the case of X sieves, the pore diameters may range between about 6 and 14 A., depending upon the metal ions present, and this is likewise the case in the Y sieves, although the latter usually are found to have crystal pores of about 9 to 10 A. in diameter.

In the case of zeolitic type cracking bases, it is desirable to deposit the hydrogenating metal thereon by ion eX- change. This can be accomplished by digesting the zeolite with an aqueous solution of a suitable compound of the desired metal, wherein the metal is present in a cationic form, and then reducing to form the free metal, as described for example in Belgian Patent No. 598,686.

Utilizing molecular sieve catalysts of the above description, containing a Group VIII noble metal hydrogenating component, suitable low-temperature hydrocracking conditions for use herein are summarized as follows:

Low-temperature hydrocracking conditions Reforming of the hydrocrackate gasolines produced herein may if desired be carried out under substantially conventional reforming conditions. Such conditions comprise: Temperatures of about 800l,000 F., space velocities between about 0.5 and 5.0, pressures between about and 800 p.s.i.g., and hydrogen rates between about 3,000 and 12,000 s.c.f/b. of feed. Suitable reforming catalysts comprise a minor proportion of Group VIII noble metal, e.g., platinum or palladium, supported upon a relatively non-cracking adsorbent carrier such as activated alumina. If desired such catalyst may be further activated by impregnation with minor amounts of acidic halides such as HF.

Reference is now made to the accompanying FIGURE l which is a owsheet illustrating a preferred modification of the invention embracing two stages of hydrocracking with separate reforming of the light and heavy hydrocrackate gasoline fractions. The initial feedstock, comprising a sulfurand nitrogen-contaminated gas oil, is brought in via line 2, mixed with recycle and fresh hydrogen from line 4, preheated to hydroiining temperatures in heater 6, and passed into catalytic hydroner 8, containing for example a bed of cobalt molybdate-alumina catalyst. Hydrofining in hydroiiner 8 is carried out under substantially conventional conditions, e.g., temperatures, 600-850 F.; pressures, SOO-3,000 p.s.i.g., space velocities, 0.3 to 5; and hydrogen rates of about 500 to 15,000 s.c.f./b. of feed. It is desirable to correlate hydroning conditions so that the liquid product from the hydrofiner will contain less than about 50 parts per million of organic nitrogen. The resulting ammoniaand hydrogen sulfide-containing effluent from hydrofiner 8 is withdrawn via line 10, and transferred without intervening treatment to first-stage hydrocracker 12, wherein hydrocracking is carried out at relatively high temperatures to compensate for the presence of ammonia in the hydrofmer efHuent. Suitable temperatures may range between about 675 and 850 F., under conditions otherwise similar to those described above for the low-temperature hydrocracking. Eflluent from hydrocracker 12 is withdrawn via line 14, washed with water injected via line 16, condensed in cooler 18 and passed into high-pressure separator 20, wherein a three-phase separation takes place. Spent wash water containing dissolved ammonium sulfide is withdrawn via line 22, and hydrogen-rich recycle gas via line 24. This recycle gas is substantially free of ammonia, 'but still contains substantial amounts of hydrogen sulfide, due to its relative insolubility in water.

High-pressure condensate from separator 20 is Withdrawn via line 26, blended via line 49 with high-pressure condensate from low-temperature hydrocracker 36, and the mixture is then flashed into low-pressure separator 28, from which light hydrocarbon flash gases are exhausted via line 30. Low-pressure condensate from separator 28 is then transferred via line 32 to one or more fractionating columns, illustrated as a single unit 34, which serves the purpose of separating the combined hydrocracker efiiuents into alight C4-C6 gasoline fraction which is withdrawn via line 52, appropriate intermediate-boilingrange hydrocrackate gasoline fractions for reforming, and unconverted oil boiling above the gasoline range which serves as feedstock to low-temperature hydrocracker 36. The latter fraction is withdrawn as bottoms via line 38, mixed with a bleed stream of hydrogen sulfide-containing recycle `gas from line 40, and with second-stage recycle gas from line 42. This mixture is then passed into lowtemperature hydrocracker 36 via preheater 44, where hydrocracking proceeds under the low-temperature conditions described above. Effluent from hydrocracker 36 is withdrawn via line 46 and passed into high-pressure separator 48 via condenser S0. High-pressure condensate in separator 48 is then withdrawn via line 49 and blended with condensate from separator 20 as previously described.

Returning to fractionating column 34, a light side-cut fraction (C7 to about 290 F. `boiling range) is withdrawn via line 54, mixed with hydrogen-rich recycle gas from line 56, preheated to reforming temperatures in heater 58, and passed into low-:pressure reformer 60 which preferably contains a non-halided platinum-alurnina reforming catalyst. Reforming is carried out in reformer 60 at low pressures of about 20G-400 psig., and at relatively low temperatures of about S-890 F.

A heavy side-cut gasoline fraction boiling between about 290 and 400 F. is withdrawn from fractionator 34 lvia line 62, mixed with recycle hydrogen from line 64, preheated -in heater 66, and passed into highapressure reformed 68 which .preferably contains a halided platinum-alumina c-atalyst, and wherein relatively severe conditions `of about 900-950 F. and pressures of about 400-600 p.s.'i.g. are employed. Effluent from reformer 68 is withdrawn via line 70 and passed into high-pressure separat-or 72 via condenser 74, from which recycle hydrogen is withdrawn via line `64. High-pressure reform'ate in separator 72 is then withdrawn and depressured into line 76 where it mingles with relatively low-pressure reformate `from line 78 (comprising the liquid product from reformer 60 which was condensed in cooler 80 and transferred to high-pressure separator 82).

6 oils wa-s subjected to two-stage hydrocracking with integral pre-hydroflning as illustrated in FIGURE l. The feed blend had the following characteristics:

Boiling range F. 400-870 Gravity, API 22.8 Sulfur, weight percent 1.27 Nitrogen, weight percent 0.214

1 SiOz/AlzOs mole-ratio=4.7; MgO/Al203=0.5.

The low-pressure combined reformates in line 76 is then flashed into lowdpressure separator 80, from which light flash gases are withdrawn via line 82. Full range O44- reformate is then withdrawn via line 84 and blended with the C4-C6 light hydroerackate gasoline in line 52. The resulting [blend may then be passed into conventional fractionating equipment not shown to separate out butanes and rec-over the final gasoline product or products of desired volatility characteristics.

Reference is now made to the attached FIGURE 5, which is a graph depicting the results obtainable in a com- -bined processing scheme substantially as described in connection with FIGURE l. lFrom this graph, it will be noted that at any total product C54- octane level between about 96 and 104, an yoverall 3-4% increase n liquid yield is obtainable when hydrocracker 36 is operated at 553 F. in the presence of hydrogen sulfide, as compared to operations wherein said hydrocracker is operated at 639 F. in the presence of hydrogen sulfide, or at 526 F. in the absence of hydrogen sulfide. The data on which the relationship shown in FIGURE 5 is based was obtained in experimental hydrocracking-re forming runs as described in the following example:

EXAMPLE I. Hydrocrackng.-A gas oil feed blend of catalytic cracking cycle oil, straight-run and coker distillate gas The combined firstand second-stage products from each of the three runs were separately fractionated to give the following hydrocrackate product fractions:

II. Reforming-Each of the C7-290 F. and 290- 400 F hydrocrackate fractions was then subjected to reforming under a Variety of conditions to give a range of product octane values. In the case of the C7-290 F. fractions, a non-halogenated 0.35 weight percent Pt- A1203 catalyst was employed, while for the 290 400 F. fractions a halided (Cl) 0.35% Pt-Al203 catalyst was used. The significant conditons and results of the reforming runs were as follows:

Results substantially similar to those described in the above example are obtained when other hydrocracking Table 3 Reforming Conditions 1 C5-I-Yield,

Vol. percent Cri-Octane, Reforming Feed IICr Fr F-1-I-3 ml.

Temp., F. Pr., p.s.i.g. LHSV Feed TEL A1-C7-290 F. ex-Sweet Hydroeracking 870 225 1. 0 29. 2 101. 0 ai; 526 F. 900 225 1. 0 26. 3 102. 8 915 225 1.0 25. 9 104. 8

B 1-C1-o290" F. eX-Sour I-Iydrocracking g at 553 F' 900 225 1. 0 31. 0 104. s 915 225 1. 0 30. 0 105. 6

C1Q1290 F. ex-Sour Hydrocraeking at g (8) g 639 F' 885 225 1. 0 29. 2 103. 3 900 225 1. 0 26. 1 104. 6

.[12--290-400D F. err-Sweet Hydroeraeking 900 425 2.0 41.0 98.6 at 526 F. 930 425 2. 0 37. 3 101. 945 425 2. 0 36. 2 102. 8

Iig-2903400" F. ex-Sour Hydrocracking zg 2 i at 553 F' 930 425 2. 0 32. 0 101. 7 945 425 2. 0 31. 4 102. 9

02-2903400" F. ex-Sour Hydroeraeking g (55 at G39 F 930 425 2. 0 29. s 101. 0 945 425 2. 0 28. 3 103. 2

1 H2 oil ratio, 7.5 Ms.c.f./b. throughout.

The yield-octane data from Table 3 is plotted in graph form in the attached FIGURES 2 and 3. No significant overall conclusions can be drawn from this data however, because it does not include the contributing yield-octane values 4of the corresponding C5-CG hydrocrakate fractions which were not subjected to reforming.

To arrive at an overall comparison of the three hydrocracking alternates, reference is made to the attached FIGURES 4 and 5. The graph in FIGURE 4 was constructed by simply adding the reformate yield gures for feeds A1 and A2, B1 and B2, C1 and C2 of FIGURES 2 and 3, vertically, at two or more octane levels, in order to obtain the proper slope for the total reformate yield-octane curves of FIGURE 4.

To `obtain the final overall yield-octane values depicted in FIGURE 5, several points on each of the three curves of FIGURE 4 were arithmetically averaged with the respective C5-C6 hydrocrackate yield-octane values from hydrocracking runs A, B and C, according to the equation:

where V1 and V2 are the respective volumes, ON1 and ONZ the respective octane numbers, and ONav the resultant average octane number. From this data, it is clear that, when the second stage of the hydrocracking operation is carried out at low temperatures in the presence of hydrogen sulfide, there is a 3-4% yield advantage at various octane levels, as compared to the other depicted hydrocracking alternates.

It should be kept in mind also that the foregoing data is based on a hydrocracking operation wherein only about half of the hydrocrackate gasoline is produced in the second stage, the remainder being produced in the rst stage where conditions are not optimum for maximum yield-octane advantage. When all of the hydrocracking is carried out under the optimum conditions shown for the second stage, the resultant yield-octane advantage is even more pronounced.

conditions and catalysts, and other reforming catalysts and conditions within the purview of this invention are employed in lieu of those illustrated. It is therefore not intended that the invention be limited to any of the details described above, but only broadly as defined in the following claims:

We claim:

1. A multi-stage hydrocracking-reforming process for converting a gas oil feedstock containing sulfur and nitrogen compounds to high-octane gasoline in maximum liquid o yields, which comprises:

(A) subjecting said feedstock plus added hydrogen to catalytic hydrofining without substantial cracking of hydrocarbons;

(B) subjecting total hydrogen sulfideand ammoniacontaining efuent from said hydrofining to a first stage of catalytic hydrocracking at a temperature between about 675 and 850 F.;

(C) separating the efhuent from said first-stage hydrocracking into a iirst-stage C5-C6 hydrocrackate gasoline fraction, an intermediate-boiling-range rststage hydrocrackate gasoline boiling predominantly below 290 F., a heavy first-stage hydrocrackate gasoline boiling predominantly above 290 F., and a substantially sulfurand nitrogen-free unconverted gas oil;

(D) subjecting said unconverted gas oil plus added hydrogen to a second stage of catalytic hydrocracking in the presence of a Group VIII noble metal hydrocracking catalyst at a temperature between about 400 and 625 F., a pressure between about 500 and 2,500 p.s.i.g., and in the presence of suflicient sulfur to provide a hydrogen sulfide concentration greater than about 0.01 millimole per mole of hydrogen therein;

(E) separating the eiuent from said second-stage hydrocracking into a second-stage C5-C6 hydrocrackate gasoline, an intermediate-boiling-range second-stage hydrocrackate gasoline boiling predominantly below 290 F., a heavy second-stage hydrocrackate gasoline boiling predominantly above 290 F., and a 9 10 recycle gas Oil which is recycled to said second hymaintain a hydrogen sulfide concentration above about 1 drocracking stage; millimole thereof per mole of hydrogen.

(F) subjecting said rstand second-stage intermediate- 3. A process as dened in claim 1 wherein said hydroboiling-range hydrocrackate gasolines in admixture cracking catalyst comprises a minor proportion of a Group to catalytic reforming in the presence of a Group 5 VIII noble metal hydrogenation component deposited up- VIII noble metal reforming catalyst at a pressure on a crystalline zeolitic molecular sieve cracking base havbetween about 200 and 400 p.s.i.g., and a temperaing a SiO2/Al203 mole-ratio between about 2.5 and 10, ture between about 825 and 925 F., and recoverand comprising zeolitic cations selected from the class ing therefrom a C5| light reformate gasoline prodconsisting of hydrogen ions and divalent metal ions. uct; lo 4. A process as defined in claim 3 wherein said zeolitic (G) subjecting said rstand second-stage heavy hydrocrackate gasolines in admixture to a separate catmolecular sieve cracking base is a Y molecular sieve.

alytic reforming operation in the presence of a Group References Cited by the Examiner VIII noble metal reforming catalyst at temperatures UNITED STATES PATENTS and pressures relatively higher than those employed 15 2,945,806 7 /1960 Ciapetta 208 110 for reforming said interrnediate-boiling-range gaso- 2,983,670 5 /1961 Seubold 208 110 lines in step (F), and recovering therefrom a C5-l- 3,005,770 10/1961 Lutz 208 79 heavy reformat@ gasoline product; and 3,008,895 11/1961 Hansford et a1. 2o8-112 (H) blending said heavy reformate gasoline product, 3,047,490 7/ 1962 Myers 208-59 said light reformate gasoline product, and said rst- 20 3,099,617 7/ 1963 Tulleners 20S-110 and second-stage C-Cf,` hydrocrackate gasolines to 3,119,763 1/ 1964 Haas 20S- 109 produce a full-range C5| gasoline product. 3,132,090 5/1964 Helfrey et al. 20S- 110 2. A process as dened in claim 1 wherein suicient sulfur is added in said second hydrocracking stage to DELBERT EGANTZPnmmy Examiner' ALPHONSO D. SULLIVAN, Examiner.

Claims (1)

1. A MULTI-STAGE HYDROCRACKING-REFORMING PROCESS FOR CONVERTING A GAS OIL FEEDSTOCK CONTAINING SULFUR AND NITROGEN COMPOUNDS TO HIGH-OCTANE GASOLINE IN MAXIMUM LIQUID YIELDS, WHICH COMPRISES: (A) SUBJECTING SAID FEEDSTOCK PLUS ADDED HYDROGEN TO CATALYTIC HYDROFINING WITHOUT SUBSTANTIAL CRACKING OF HYDROCARBONS; (B) SUBJECTING TOTAL HYDROGEN SULFIDE- AND AMMONACONTAINING EFFLUENT FROM SAID HYDROFINING TO A FIRST STAGE OF CATALYTIC HYDROCRACKING AT A TEMPERATURE BETWEEN ABOUT 675* AND 850*F; (C) SEPARATING THE EFFLUENT FROM SAID FIRST-STAGE HYDROCRACKING INTO A FIRST-STAGE C5-C6 HYDROCRACKATE GASOLINE FRACTION, AN INTERMEDIATE-BOILING-RANGE FIRSTSTAGE HYDROCRACKATE GASOLINE BOILING PREDOMINANTLY BELOW 290*F., A HEAVY FIRST-STAGE HYDROCRACKATE GASOLINE BOILING PREDOMINANTLY ABOVE 290*F., AND A SUBSTANTIALLY SULFUR- AND NITROGEN-FREE UNCONVERTED GAS OIL; (D) SUBJECTING SAID UNCONVERTED GAS OIL PLUS ADDED HYDROGEN TO A SECOND STAGE OF CATALYTIC HYDROCRACKING IN THE PRESENCE OF A GROUP VIII NOBLE METAL HYDROCRACKING CATALYST AT A TEMPERATURE BETWEEN ABOUT 400* AND 625*F., A PRESSURE BETWEEN ABOUT 500 AND 2,500 P.S.I.G., AND IN THE PRESENCE OF SUFFICIENT SULFUR TO PROVIDE A HYDROGEN SULFIDE CONCENTRATION GREATER THAN ABOUT 0.01 MILLIMOLE PER MOLE OF HYDROGEN THEREIN; (E) SEPARATING THE EFFLUENT FROM SAID SECOND-STAGE HYDROCRACKING INTO A SECOND-STAGE C5-C6 HYDROCRACKATE GASOLINE, AN INTERMEDIATE-BOILING-RANGE SECOND-STAGE HYDROCRACKATE GASOLINE BOILING PREDOMINANTLY BELOW 290*F., A HEAVY SECOND-STAGE HYDROCRACKATE GASOLINE BOILING PREDOMINANTLY ABOVE 290*F., AND A RECYCLE GAS OIL WHICH IS RECYCLED TO SAID SECOND HYDROCRACKING STAGE; (F) SUBJECTING SAID FIRST- AND SECOND-STAGE INTERMEDIATEBOILING-RANGE HYDROCRACKATE GASOLINES IN ADMIXTURE TO CATALYTIC REFORMING IN THE PRESENCE OF A GROUP VIII NOBLE METAL REFORMING CATALYST AT A PRESSURE BETWEEN ABOUT 200 AND 400 P.S.I.G., AND A TEMPERATURE BETWEEN ABOUT 825* AND 925*F., AND RECOVERING THEREFROM A C5+LIGHT REFORMATE GASOLINE PRODUCT; (G) SUBJECTING SAID FIRST- AND SECOND-STAGE HEAVY HYDROCRACKATE GASOLINES IN ADMIXTURE TO A SERPARATE CATALYTIC REFORMING OPERATION IN THE PRESENCE OF A GROUP VIII NOBLE METAL REFORMING CATALYST AT TEMPERATURES AND PRESSURES RELATIVELY HIGHER THAN THOSE EMPLOYED FOR REFORMING SAID INTERMEDIATE-BOILING-RANGE GASOLINES IN STEP (F), AND RECOVERING THEREFROM A C5+ HEAVY REFORMATE GASOLINE PRODUCT; AND (H) BLENDING AID HEAVY REFORMATE GASOLINE PRODUCT, SAID LIGHT REFORMATE GASOLINE PRODUCT, AND SAID FIRSTAND SECOND-STAGE C5-C6 HYDROCRACKATE GASOLINES TO PRODUCE A FULL-RANGE C5+ GASOLINE PRODUCT.

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