MXPA00006015A - Dewaxing process - Google Patents

Abstract

The process of the invention for converting a hydrocarbon oil includes the following steps:(1) contacting a hydrocarbon oil feedstock in the presence of added hydrogen gas with a catalyst selected from the group consisting of a SAPO-11, SAPO-31 or SAPO-41 intermediate pore size silicoaluminophosphate molecular sieve and a hydrogenation component, and mixtures thereof, wherein at least a portion of the feedstock is converted;and (2) passing at least a portion of the converted feedstock to a fractionator, wherein at least a portion of the converted feedstock is fractionated, thereby producing at least one overhead fraction and one bottoms fraction;and (3) mixing at least a portion of the bottoms fraction with the hydrocarbon oil feedstock in step (1).

Description

PROCESS FOR DEPARAFINATION FIELD OF THE INVENTION The present invention relates to a process for catalytically dewaxing lubricating oils. More specifically, the invention relates to a process for dewaxing a hydrocarbon oil feedstock, wherein at least a portion of the bottoms of the fractionator is recirculated to the feedstock.

II. BACKGROUND OF THE INVENTION Certain processes for dewaxing petroleum distillates are well known. Deparation is required when highly paraffinic oils are to be used in products that must be mobile at low temperatures, e.g., lubricating oils, heating oils and fuel for combustion turbines. The normal paraffins of higher molecular weight linear chain, substituted and slightly branched present in such oils, are paraffins that cause points of high critical flow temperature and high turbidity points. If low critical flow temperature points are obtained, the paraffins should be completely or partially removed. In the past, various solvent removal techniques were employed to remove such paraffins, such as propane dewaxing and MEK deparaffinization; however, they have high operating costs, significant environmental impacts and produce oils that are inferior to catalytic dewaxed oils. Catalytic dewaxing processes are more economical and remove paraffins by selectively isomerizing and paraffinic components of the catalytic raceway to produce lower molecular weight products, some of which could be removed by distillation.

Due to their selectivity, known dewaxing catalysts generally comprise an aluminosilicate zeolite having a pore size that admits the straight chain n-paraffins either alone or with only slightly branched chain paraffins, but which excludes the materials more highly branched, cycloaliphatic and higher aromatics. Zeolites such as ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35 and ZSM-38 have been proposed for this purpose in dewaxing processes. Its use is described in Pat. U.S. Nos. 3,700,585; 3,894,938; 4,176,050; 4,181,598; 4,222,855; 4,229,282 and 4,247,388, the descriptions of which are incorporated herein by reference.

Since many dewaxing processes of this type work by means of catalytic reaction thermoforming reactions, a number of useful products have become degraded to higher molecular weight materials. For example, wax paraffins could be thermally catalyzed to butane, propane, ethane and methane, and in this way, lighter paraffins that do not contribute to the paraffinic nature of the oil. Because their lighter products are generally lower in value than higher molecular weight materials. It is desirable to limit the degree of catalytic curing termof which is carried out during a catalytic dewaxing process.

European Patent Application No. 225,053, describes a process for producing lubricating oils by partially dewaxing a lubricant base feed, by isomerization dewaxing followed by a selective dewaxing step. The dewaxing step by isomerization is carried out using a higher silica zeolite dewaxing catalyst such as silica Y or beta zeolite, which produces the isomerization of the paraffinic components of the base feed to fewer waxy branched chain isoparaffins. The selective deparaffinization step could be either a solvent, e.g., MEK dewaxing operation or a catalytic dewaxing, preferably using a highly formed zeolite such as ZSM-22 or ZSM-23.

Pat. U.S. No. 4,437,976 discloses a two stage hydrocarbon dewaxing hydrotreatment process wherein the critical fluidity point of a boiling hydrocarbon feedstock from 400 ° F to 1050 ° F., is reduced by the catalytic dewaxing of the charge feed in the presence of a zeolite catalyst and the subsequent subjection of at least the liquid portion thereof to hydrogenation in the presence of a hydrotreating catalyst comprising a hydrogenation component and a crystalline material porous siliceous of the zeolite class ZSM-5, ZSM-23 and ZSM-35.

Pat. U.S. No. 4,575,416 by Chester et al. describes a hydrodeparaffinization process with a first zeolite catalyst having a coercion index of not less than 1, a second catalyst component of specific characteristics and a hydrogenation component.

Pat. U.S. No. 5,149,421 shows a dewaxing catalyst that provides superior selectivity with respect to the nature of the products obtained in a dewaxing process. Using a molecular sieve catalyst of silicoaluminophosphate of intermediate pore size in the dewaxing process, the hydrocarbon feed streams are effectively deparaffinized and the products obtained are of higher molecular weight than those obtained using other aluminosilicate zeolites. The products obtained from the dewaxing process have better viscosities and viscosity indices at a given critical flow temperature point as compared to prior art processes described above using aluminosilicate zeolites.

However, it would be advantageous to have a process that provides increased performance in the known processes, or reduction of the point of the critical flow temperature to the same performance. The present invention provides such a process.

III. BRIEF DESCRIPTION OF THE INVENTION The present invention overcomes the problems and disadvantages of the prior art by providing a process for catalytically dewaxing a hydrocarbon feedstock that produces superior performance of lubricating oil.

The process of the invention for converting a hydrocarbon oil includes the following steps: (1) contacting a hydrocarbon stream feed in the presence of hydrogen gas added with a catalyst selected from the group consisting of a molecular sieve of silicoaluminophos of intermediate pore size SAPO-11, SAPO 31 or SAPO 41 and a hydrogenation component, and mixtures thereof, wherein at least a portion of the feedstock is converted; and (2) passing at least a portion of the converted feedstock to a fractionator, wherein at least a portion of the converted feedstock is fractioned, thereby producing at least a head fraction and a fraction of bottoms; and (3) mixing at least a portion of the bottom fraction with the hydrocarbon oil feedstock in step (1).

IV. BRIEF DESCRIPTION OF THE DRAWING Figure 1 represents a simplified schematic flow chart of one embodiment of the process of the invention.

V. DETAILED DESCRIPTION OF THE PREFERRED MODALITIES A. Stages of the Process The process of the invention for converting a hydrocarbon oil includes the following steps: (1) contacting a hydrocarbon stream feed in the presence of hydrogen gas added with a catalyst system that contacts the catalyst selected from the group consisting of a molecular sieve of si li coaluminofos fat or intermediate pore size SAPO-11, SAPO 31 or SAPO 41 and a hydrogenation component, and mixtures thereof, wherein at least a portion of the feedstock is converted; and (2) passing at least a portion of the converted feedstock to a fractionator, wherein at least a portion of the converted feedstock is fractioned, thereby producing at least a head fraction and a fraction of bottoms; and (3) mixing at least a portion of the bottom fraction with the hydrocarbon oil feedstock in step (1).

The catalyst system further optionally includes a catalyst selected from the group consisting of an intermediate pore size aluminosilicate zeolite catalyst, an amorphous catalyst, and mixtures thereof. For pre-ratios, the feed could be hydrotroped or extracted by solvent and hydrotreated. This type of process and typical hydrophobicization conditions are described in U.S. Pat. No. 4,921,594, filed May 1, 1990 by Miller, which is hereby incorporated by reference in its entirety. Post-treatments may include erroneous hydrot, discussed later.

Without being limited by theory, in one embodiment, the mechanism of deparaffinization is isomerization and / or thermodynamics of catalytic compounds of paraffinic compounds. Typically, cat-alitic dewaxing, e.g., Chevron's ISODE AXING catalytic dewaxing process, operates to improve the point of critical flow temperature and the viscosity index of a feedstock, compared to solvent dewaxing.

B. Feeding material The process of the invention could be used to dewax a variety of hydrocarbon oil feedstocks classified in general, such as any paraffin hydrocarbon feedstock, lubricating oil feedstock or intermediate distillate oil. Feeding materials include distilled fractions, e. g. , hydrotrophied hydrotheses, up to the materials of higher boiling points such as oils extracted by solvents and deasphalted. The feedstock will normally be a C10 + feedstock that generally boils above 350 ° F, since the lighter oils will usually be free of significant amounts of paraffinic components. However, the process is particularly useful with paraffinic distillate materials, such as intermediate distillate materials including gaseous oils, kerosenes and combustion turbine fuels, lubricating oil materials, heating oils and other distilled fractions whose temperature point of critical fluidity and viscosity need to be maintained within certain specified limits. Lubricating oil materials will generally boil above 230 ° C (450 ° C), more usually above 315 ° C (600 ° F).

Hydroprocessed materials are a convenient source of materials of this type and also, of other distilled fractions since they have a higher hydrogen content on materials processed by solvents and are usually relatively free of heteroatoms (eg, sulfur and nitrogen compounds) that they can impart the development of the dewaxing and hydro terminated catalysts. The feed material of the present process will normally be a C10 + feedstock containing paraffins, olefins, naphthenes, aromatic and heterocyclic compounds and a substantial proportion of higher molecular weight n-paraffins and slightly branched and substituted paraffins that contribute to the paraffinic nature of the feeding material.

During processing, the feed molecules undergo some thermo-catalytic or thermo-hydrophobic reaction to form the liquid-range materials that contribute to a low viscosity product. The degree of catalytic curing termof which occurs, however, is limited to preserve the performance of valuable liquids.

Typical feed materials include light gas oil, heavy gas oils and reduced crude oils that boil above 350 ° F. In one embodiment, the feedstock contains a major portion of a hydrocarbon oil feedstock that boils above about 350 ° F and contains straight chain and slightly branched chain hydrocarbons. The term "major portion" means more than 50 weight percent.

While the process of the invention can be practiced with utility when the feed contains organic nitrogen (impurities containing nitrogen), it is preferred that the organic nitrogen content of the feed be less than 50 pppm, more preferably less than 10 pppm. Particularly good results are experienced in terms of the activity and length of the catalyst cycle (period between successive regenerations or the beginning and first regeneration), when the feed contains less than 10 pppm of organic nitrogen.

C. Molecular Screen Catalyst Compositions of Sil i Coalumino Phosphate 1. Generalities Molecular screens of intermediate pore sizes (SAPOs) are catalysts used in the process of the invention. The SAPOs are any conventional intermediate pore SAPO. The SAPOs are used separately or in combination with zeolites and / or amorphous catalysts. Examples of molecular silicoaluminophosphate screens that can be used in this invention are described in Pats. U.S. Nos. 4,440,871 and 5,149,421, the descriptions of which are incorporated herein by reference.

The intermediate pore size silicoaluminophosphate molecular sieve catalyst is employed in the process of the invention to convert the paraffinic components to non-paraffinic components and reduce their point of critical flow temperature from about 30 ° F to about 60 ° F. The amount of catalyst used is dependent on the reaction conditions.

In a preferred embodiment, the final catalyst will be a compound and includes a molecular sieve of silylaluminophosphate fat or intermediate pore size, a metal component of platinum or palladium and an inorganic oxide matrix. The molecular sieves of siloaluminophos fat or pore size appropriate for use in the process of this invention include SAPO-11, SAPO-31 and SAPO-41. The most preferred silicoaluminophosphate is SAPO-11, the most preferred metal component is platinum and the most preferred binder is alumina. The descriptions of SAPO-11, SAPO-31 and SAPO-41 and methods for making them are given in the patents referenced above and in R. Szostak, Ha ndbook of Mol ecul ar Si eve s (Van Norstrand Reinhold 1992), pages 410-413, 415-416, 419-420, the descriptions of which are incorporated herein by reference. 2. Special Repairs: The molecular sieve can be composed of other materials resistant to temperatures and other conditions used in the dewaxing process. Such matrix materials include active and inactive materials and synthetic or naturally occurring zeolites, as well as inorganic materials such as clays, silica and metal oxides. The latter could occur naturally or in the form of gelatinous precipitates, colloidal suspensions or gels that include mixtures of silica and metal oxides. The inactive materials serve appropriately as binders or as diluents to control the amount of conversion in the dewaxing process, so that the products can be obtained economically without employing other means to control the rate of reaction.

The illicoaluminophos fatos could be combined with clays that occur naturally, e.g., ben'tonite and kaolin. These materials, i.e., clays, oxides, etc., function, in part, as binders for the catalyst. It is desirable to provide a catalyst that has good agglomeration resistance, because in the refining of the oil the catalyst is often subjected to harsh handling and large forces in the reactor. This tends to break the catalyst into fragments that can be connected in the reactor.

The naturally occurring clays that can be compounded with the SiOluminum fato include the montmorilloni tay kaolin families, these families include the sub-bent on t and the caolins commonly known as clays Dixie, McNamee, Georgia and Florida. and others, in which the main mineral constituent is halosite, kaolinite, nacrite or anauxite. Fibrous clays such as halosite, sepiolite and attapulgite can also be used as supports. Such clays can be used in the raw state as originally extracted from the mine or initially subjected to calcination, acid treatment or chemical modification.

In addition to the above materials, "s il and coaluminophos can be composed of porous matrix materials., eg, inorganic oxide matrix, and mixtures of matrix materials, such as silica, alumina, titania, magnesia, silica-alumina, silica-magnesia, yes lice-zirconia, yes lice-toria, silica-berilia, s 1 ice-tint, t-aniazirconia as well as ternary compositions, such as lice-alumina-toria, silica-alumina-titania, yes 1 ice-alumina -magne siay yes.lice-magnesia-zirconia. The matrix can be in the form of a co-gel or an intimate physical mixture.

The aluminum-aluminum-fat catalysts used in the process of this invention can also be composed of other zeolites, such as synthetic or natural faujasites (e.g., X and Y), erionites and mordenites. They can also be composed of purely synthetic zeolites such as those of the ZSM series. The combination of the zeolites can also be composed in a porous inorganic matrix.

D. Zeolites Examples of aluminosilicate zeolite catalysts suitable for use in the process of the invention include ZSM-22, ZSM-23 and ZSM-35. These are shown in R. Szostak, Ha n dbook of Mol e cul a r Si eves (Van Norstrand Reinhold 1992), on pages 538-542 and 545-546, which are incorporated herein by reference, and in U.S. Pat. Nos. 4,481,177; 4,076,842 and 4,016,245, the descriptions of which are incorporated herein by reference.

The molecular sieve catalyst of silai coaluminofos for the aluminosilicate zeolite catalyst are employed in the process of the invention in an effective weight ratio of the molecular sieve of 1-umlaluminofes fat or of pore-size intermediate to the sieve. molecular weight of aluminosilicate zeolite to increase the yield of the converted feed material. Preferred relationships are from about 1: 5 to about 20: 1. The zeolite used in the process preferably has a measured coercion index of about 400 ° C to about 454 ° C of about 4 to about 12.

In another embodiment of the process of the invention, SSZ-48, preferably predominantly in the hydrogen form, can be used in the dewaxing process of the invention. Without being limited by theory, SSZ-48 is thought to deparaffin by selectively removing the side chain paraffins. Typically, the viscosity index of the dewaxed product is improved (compared to the dewaxed solvent feed) when the paraffinic feed is contacted with SSZ-48 under the conditions of dewaxing by isomerization (also referred to as hydrodesparaffin).

In the preparation of SSZ-48 zeolites, a decahydroquinolinium cation is used as a crystallization matrix. The decahydroquinolinio cation could have the following structure: C cHUCHoCH2CH3 The anion (X ') associated with the cation could be any anion that is not detrimental to the formation of the zeolite. Representative anions include halogen, e.g., fluorine, chlorine, bromine and iodine, hydroxide, acetate, sulfate, tetrafluoroborate, carboxylate and the like. Hydroxide is the most preferred anion.

In general, SSZ-48 is prepared by contacting an active source of one or more oxides selected from the group consisting of monovalent elementary oxides, divalent elemental oxides, trivalent elemental oxides and elemental tetravalent oxides with the cation matrix agent of decahydroquinolinium.

SSZ-48 is prepared from a reaction mixture having the composition shown in the following Table 1.

TABLE 1 Reaction Mixture Typical preferred Y02 / WaOb 10-100 15-40 OH- / Y02 0.10-0.50 0.20-0.30 Q / Y02 0.05-0.50 0.10-0.20 M2 / n / Y02 0.01-0.10 0.03-0.07 H20 / Y02 20-80 30-45 wherein Y is silicon, germanium or a mixture thereof; it is aluminum, gallium, iron, boron, titanium, indium, vanadium or mixtures thereof; c is 1 or 2; d is 2 when c is 1 (i.e., is tetravalent) or d is 3 or 5 when c is 2 (i.e., d is 3 when W is trivalent or 5 when pent avalente); M is an alkali metal cation, alkaline earth metal cation or mixtures thereof; n is the valence of M (i.e., 1 or 2); and Q is at least one decahydroquinolinium cation, and a is 1 or 2 and b is 2 when a is 1 (i.e., is tetravalent) and b is 3 when a is 2 (i.e., W is trivalent).

In practice, SSZ-48 is prepared by a process that includes: preparing an aqueous solution containing sources of at least one oxide capable of forming a molecular crystalline screen and a decahydroquinolinium cation having an anionic counterion that is not detrimental to the formation of SSZ-48; (b) maintaining the aqueous solution under conditions sufficient to form SSZ-48 crystals; Y (c) recover the crystals of SSZ ' Therefore, SSZ-48 could comprise the crystalline material and the matrix agent in combination with the metallic and non-metallic oxides linked in tetrahedral coordination through the shared oxygen atoms to form a cross-linked three-dimensional crystal structure. The metal and non-metal oxides comprise one or a combination of oxides of a first tetravalent element, and one or a combination of a second tetravalent element different from the first tetravalent, element or trivalent, element or pentavalent element or mixtures thereof. The tetravalent element is preferably selected from the group consisting of silicon, germanium and combinations thereof. More preferably, the first tetravalent element is silicon. The second tetravalent element (which is different from the first tetravalent element), trivalent element and pentavalent element is preferably selected from the group consisting of aluminum, gallium, iron, boron, titanium, indium, vanadium and combinations thereof. More preferably, the second trivalent or tetravalent element is aluminum or boron.

Typical sources of aluminum oxide for the reaction mixture include aluminates, alumina, aluminum colloids, aluminum oxide coated in colloidal suspension, hydrated alumina gels such as Al (OH) 3, and aluminum compounds, such as A1C13 and A12. (S04) 3. Typical sources of silicon oxide include silicates, silica hydrogel, silicic acid, gaseous silica, colloidal silica, tetra-alkyl orthosilicates and silica hydroxides. Boron, as well as gallium, germanium, titanium, indium, vanadium and iron, can be added in the forms corresponding to their aluminum and silicon counterparts.

A source of zeolite reagent could provide a source of aluminum or boron. In most cases, the zeolite source also provides a source of silica. The source of zeolite in its aluminum-free or boron-free form could also be used as a silica source, with additional silica added, using, for example, the conventional sources listed above. The use of a zeolite source reagent as a source of alumina for the present process is more fully described in U.S. Pat. No. 5,187,132, filed on February 16, 1993 by 'Zones et al. entitled "Preparation of Borosilicate Zeolites", the description of which is incorporated herein by reference.

Typically, an alkali metal hydroxide and / or alkaline earth metal hydroxide, such as sodium, potassium, lithium, cesium, rubidium, calcium and magnesium hydroxide, is used in the reaction mixture; however, this component can be omitted provided the equivalent basicity is maintained. The matrix agent could be used to provide the hydroxide ion. In this way, the ion exchange, for example, the halide for the hydroxide ion, could be beneficial, whereby the required amount of the alkali metal hydroxide is reduced or eliminated. The alkali metal cation or alkaline earth cation could be part of the crystalline oxide material as it was synthesized, to balance the charges of the valence electrons.

The reaction mixture is maintained at an elevated temperature until the crystals of the SSZ-48 zeolite are formed. The hydrothermal crystallization is usually carried out under the autogenous pressure, at a temperature between 100 ° C and 200 ° C, preferably between 135 ° C and 160 ° C. The crystallization period is typically 'greater than 1 day and preferably from about 3 days to about 20 days.

Preferably, the zeolite is prepared using moderate agitation.

During the hydrothermal crystallization step, the SSZ-48 crystals can be left to spontaneously nucleate out of the reaction mixture. The use of SSZ-48 crystals as the seeding material may be advantageous in decreasing the time necessary to complete the crystallization to occur. In addition, seeding can lead to an increased purity of the product obtained by the promotion of nucleation and / or formation of SSZ-48 on the unwanted phases. When used as seeds, SSZ-48 crystals are added in an amount between 0.1 and 10% of the weight of the silica used in the reaction mixture. í Once the zeolite has been formed, the solid product is separated from the reaction mixture by standard mechanical separation techniques, such as filtration. The crystals are washed with water and then dried, e.g., from 90 ° C to 150 ° C for 8 to 24 hours, to obtain the SSZ-48 zeolite crystals as they were synthesized. The drying step can be carried out at atmospheric or vacuum pressure.

Ssz-48, as prepared, has a mole ratio of an oxide selected from silicon oxide, germanium oxide and mixtures thereof to an oxide selected from aluminum oxide, gallium oxide, iron oxide, boron oxide, titanium oxide, indium oxide, vanadium oxide and mixtures thereof, greater than about 40; and has the X-ray diffraction lines of Table 2 below.

TABLE 2 SSZ-48 as Synthesized 2 Theta (a) d Relative Intensity (b) 6. 55 13.5 8.0 11.0 VS 9.4 9.40 M 11.3 7.82 M-W 20.05 4.42 VS 22.7 3.91 VS 24.1 3.69 VS 26.5 3.36 S 27.9 3.20 S 35.85 2.50 M (a) ± 0.3 (bl The X-ray patterns provided are based on the relative intensity scale in which a stronger line is assigned in the X-ray pattern of a value of 100: W (weak) is less than 20 M (medium) is between 20 and 40, S (strong) is between 40 and 60, VS (very strong) is greater than 60.

SSZ-48 also has a composition, as synthesized and in the anhydrous state, in terms of molar ratios, shown in the following Table 3.

TABLE 3 SSZ-48 as synthesized M2 / n / Y02 0.01-0.03 Q / Y02 0.02-0.05 wherein Y is silicon, germanium or a mixture thereof; it is aluminum, gallium, iron, boron, titanium, indium, vanadium or mixtures thereof; c is 1 or 2; d is 2 when c is 1 (i.e., W is tetravalent) or d is 3 or 5 when c is 2 (i.e., d is 3 when W is trivalent or 5 when W is pent avalente); M is an alkali metal cation, alkaline earth metal cation or mixtures thereof; n is the valence of M (i.e., 1 or 2); and Q is at least one decahydroquinolinium cation.

One method to increase the molar ratio of silica to boron is by using standard acid leaching or chelation treatments. The ratios of lower silica to alumina could also be obtained using the methods that introduce aluminum into the crystal structure. For example, the aluminum insert could be presented by the thermal treatment of zeolite in combination with an alumina binder or dissolved alumina source. Such procedures are described in U.S. Pat. No. 4,559,315, filed December 17, 1985 by Chang et al, the disclosure of which is incorporated herein by reference.

The SSZ-48 zeolites, as they are synthesized, have a crystal structure whose X-ray fine crystal diffraction pattern exhibits the characteristic lines shown in Table 2 above 'and by which is distinguished from the other known zeolites.

After calcination, the SSZ-48 zeolites have a crystal structure whose fine crystal diffraction pattern includes the characteristic lines shown in Table 4: TABLE 4 SSZ-48 calcined 2 Theta (a) d Relative Intensity (b) 6. 55 13.5 VS 8.0 11.0 VS 9.4 9.40 S 11.3 7.82 M 20.05 4.42 M 22.7 3.91 M 24.1 3.69 M 26.5 3.36 M 27.9 3.20 W 35.85 2.50 W (a) ± 0.3 The diffraction diagrams of fine X-ray crystals were determined by standard techniques. The radiation was the K-alpha / copper doublet. The heights and the positions of the peaks, as a function of 2T where? is the Bragg angle, the relative intensities of the peaks were read, and d, the interplanar spacing in Angstroms corresponding to the registered lines can be calculated.

The variation in the scattering angle measurements (two teta), due to the instrument error and the differences between the individual samples, is estimated at ± 0.30 degrees.

The X-ray diffraction pattern of Table 2 above is representative of the SSZ-48 zeolites "as synthesized" or "as they were". Minor variations in the diffraction pattern may result from variations in the molar ratio of silica to alumina or silica to boron in the particular sample, due to changes in network constants. In addition, sufficiently small crystals will affect the shape and intensity of the peaks, leading to significant peak width.

The representative peaks of the calcined SSZ-48 X-ray diffraction pattern are shown in Table 4. Calcination can also result in changes in peak intensities as compared to the "as-done" material standards. , as well as minor changes in the diffraction pattern. The zeolite produced by the exchange of the metal or other cations present in the zeolite with several other cations (such as H + or NH4 +) produces essentially the same diffraction pattern, although again, there could be minor changes in the interplanar spacing and variations in the intensities relative of the peaks. Without resisting these minor perturbations, the basic crystal network remains unchanged by these treatments.

The crystalline SSZ-48 can be used as it was synthesized, but preferably it will be thermally treated (calcined). Usually, it is desirable to remove the alkali metal cation by ion exchange and replace it with hydrogen, ammonium or any desired metal ion. The zeolite can be leached with chelating agents, e.g., EDTA or dilute acid solutions, to increase the molar ratio of silica to alumina. The zeolite can also be treated with steam; Steam treatment helps stabilize the crystal lattice against acid attack.

The SSZ-48 and any other zeolite used in this process can be used in the intimate combination with the hydrogenation components, such as tungsten, vanadium, molybdenum, rhenium, nickel, cobalt, chromium, manganese or a noble metal, such as palladium. or platinum, for applications where a hydrogenation-dehydrogenation function is desired. Platinum and palladium are preferred.

Metals could also be introduced into the zeolites, replacing some of the cations in the zeolite with the metal cations via standard ion exchange techniques (see, for example, US Patent No. 3,140,249 filed July 7, 1964 by Plank et al. al .; 3,140,251 filed July 7, 1964 by Plank et al., and 3,140,253 filed July 7, 1964 by Plank et al., the descriptions of which are incorporated herein by reference). Typical replacement cations may include metal cations, e.g., rare earths, Group IA, Group IIA and Group VII metals, as well as mixtures thereof. Of the metal cations of replacement, cations of metals such as rare earths, Mn, Ca, Mg, Zn, Cd, Pt, Pd, Ni, Co, Ti, Al, Sn and Fe are particularly preferred.

Techniques for introducing catalytically active metals into a molecular sieve are described in the literature, and pre-existing metal incorporation techniques and treatment of the molecular sieve to form an active catalyst such as ion exchange, impregnation or occlusion during the preparation of the screen, are appropriate for use in the present process. Such techniques are described in the Pats. U.S. Nos. 3,236,761; 3,226,339; 3,236,762; 3,620,960; 3,373,109; 4,202,996; 4,440,781 and 4,710,485, the descriptions of the limes are incorporated herein by reference. The amount of the metal is in the range of about 0.01% to about 10% by weight of the zeolite, preferably from about 0.2% to about 5%.

The hydrogen, ammonium and metal components can be exchanged ionically in the zeolites. They can also be impregnated with the metals, or, the metals can be physically and intimately mixed with the zeolite using the standard methods known in the art.

Typical ion exchange techniques involve contacting the synthetic zeolite with a solution containing a salt of the desired cation or replacement cations. Although a wide variety of salts can be employed, chlorides and other halides, acetates, nitrates and sulfates are particularly preferred. The zeolite is usually calcined before the ion exchange process to remove the organic matter present in the channels and on the surface, since this results in a more effective ion exchange. Representative ion exchange techniques are described in a wide variety of patents including U.S. Pat. Nos. 3,140,249 filed July 7, 1964 by Plank et al.; 3,140,251 filed July 7, 1964 by Plank et al., And 3,140,253 filed July 7, 1964 by Plank et al., The descriptions of which are incorporated herein by reference.

After contact with the saline solution of the desired replacement cation, the zeolite is typically washed with water and dried at temperatures in the range of about 65 ° C to about 200 ° C. After washing, the zeolite can be calcined in air or inert gas at temperatures in the range of about 200 ° C to about 800 ° C for periods of time in the range of 1 to 48 hours, or longer, to produce a catalytically active product especially useful in hydrocarbon conversion processes.

With respect to the cations present in the synthesized form of SSZ-48, the spatial arrangement of the atoms which form the basic crystal lattice of the zeolite remains essentially unchanged.

The hydrogenation component is present in an appropriate amount to provide a hydrodespanation catalyst and effective hydroisomerization preferably in the range of about 0.05 to 5% by weight. The catalyst could be run in such a way, to increase the isodeparaffination at the expense of catalytic reaction of thermoforming reactions.

Any of two or more zeolites used in this process could be used as a dewaxing catalyst in the form of a catalyst in the form of layers. That is, the catalyst comprises a first layer comprising, eg, zeolite SSZ-48 and at least one Group VIII metal, and a second layer comprising another aluminosilicate zeolite, eg, one which, optionally, is more selective in form than the zeolite SSZ-48. The use of the layer catalysts is described in U.S. Pat. No. 5,149,421, filed September 22, 1992 by Miller, which is hereby incorporated by reference in its entirety. The layers could also include a bed of zeolite, e.g., SSZ-48, in layer with a zeolite component designed for the hydrotreating or hydrotreating hydrotreatment. Instead of the layers, the intimately mixed catalyst systems represent another useful variant of this concept.

Amorphous catalysts The amorphous catalysts useful in the invention are any of the amorphous catalysts that have hydrogenation and / or isomerization effects in the feedstock. Such amorphous catalysts are indicated, e.g., in U.S. Pat. No. 4,383,913, the description of which is incorporated herein by reference.

These include, eg, amorphous catalytic inorganic oxides, eg, catalytically active silica-aluminas, clays, synthetic or acid activated clays, silicas, aluminas, silica-aluminas, ss 1 ice-zi rconias, silica-magnesias, alumina- borias, alumina-titanias, cross-linking or support clays and the like and mixtures thereof.

Process Conditions The process is carried out under the conditions of catalytic dewaxing. Such conditions are known and shown for example in U.S. Pat. Nos. 5,591,322; 5,149,421 and 4,181,598, the descriptions of which are incorporated herein by reference. Catalytic dewaxing conditions are highly dependent on the feed used and the point of the desired critical melt temperature. The hydrogen is preferably present in the reaction zone during the catalytic dewaxing process. The hydrogen for the feed ratio, i.e., the hydrogen flow rate, is typically between about 500 and about 30,000 SCF / bbl (standard cubic feet per barrel), preferably about 1000 to about 20,000 SCF / bbl. In general, hydrogen will be separated from the product and recirculated to the reaction zone.

The percent of fractionator funds recirculated to the feed is an effective amount to improve overall yield. Preferably, the recirculation percent is from about 1 to about 100, or more preferably from about 10 to about 50. The ratio of the bottoms of the fractionator to the crude feed is an effective ratio to reduce the point of the flow temperature critical without loss in performance or to improve overall performance, while maintaining the point of critical flow temperature. Preferably, the ratio is from about 1: 100 to about 60: 100, or more preferably 1: 100 to about 40: 100.

An aluminosilicate zeolite catalyst of intermediate pore size and / or amorphous catalyst, optionally used in the same reactor as the molecular sieve catalyst of the ilicumuminofos fato, or could be used in a separate reactor. When two or more catalysts are used in the same reactor, they could be sequentially layered or mixed. When sequentially formed in layers, the SAPO is optionally the first layer or the second layer. When two or more catalysts are used in the same reactor, they could also be intimately mixed. Any conventional catalyst bed configuration can be used in the process of the invention.

The catalytic isomerization step of the invention could be carried out by contacting the feed to be depleted with a fixed stationary bed of catalyst, with a fixed fluidized bed or with a transport bed, as desired. A simple and therefore preferred configuration is an irregular bed operation in which the feed is allowed to drain through a stationary fixed bed, preferably in the presence of hydrogen.

The catalytic dewaxing conditions employed depend on the feed used and the point of the desired critical flow temperature. Some generalizations of the process conditions for various catalytic processes are shown in Table 5 below: Table 5 Process Temp. , ° C Pressure LHSV Hidrotejrmof raccionamlento 175-485 0.5-350 bar 0.1-30 Deparaffinization 200-475 15-3000 psig 0.1-20 (250-450) (200-3000) (0.2-10) Formation of 400-600 atm.-10 bar 0.1-15 aromatics (480-550) Fractionation 127-885 subatm. -1 0.5-50 catalytic (atm -5 atm) 01 igomeriz ation 232-6492 0.1-50 0.2-502 10-2324 atm.2 * 3 0.05-205 (27-204) (0.1-10) 5 Paraffins at 100-700 0-1000 psig 0.5-405 aromatics Condensation 260-538 0.5-1000 0.5-505 alcohols psig Isomerization 93-538 50-1000 psig 1-10 (204-315) (1-4) Isomerization of 260-5932 0.5-50 atm, 0.1-1005 xylene 315-566) (1-5 atm) 2 (0.5-50) 5 38-3714 1-200 atm.4 0.5-50 xVArios hundreds of atmospheres 2Phase reaction gaseous 3 Partial hydrocarbon reaction 'Liquid phase reaction 5 HSV In the process of this invention, in general, the temperature is about 200 ° C and about 475 ° C, preferably between about 250 ° C and about 450 ° C. The pressure is typically between 15 psig and approximately 3000 psig; preferably between about 200 psig and 3000 psig. The space velocity per hour of the liquid (LHSV) will preferably be from 0.1 to 20, preferably from approximately 0.2 to 10.

The hydrogen is preferably present in the reaction zone during the isomerization process. The hydrogen to feed ratio is typically between about 500 and about 30,000 SCF / bbl (standard cubic feet per barrel), preferably from about 1000 to about 20,000 SCF / bbl. In general, the hydrogen will be separated from the product and recycled to the reaction zone.

Post-treatment s Frequently it is desired to use moderate hydrogenation (sometimes referred to as an expired hydrot). The erroneous hydrot stage is beneficial in the preparation of an acceptably stable product (e.g., a lubricating oil) since the unsaturated products tend to be unstable to air and light and tend to degrade. The hydrofinishing step can be carried out after the isomerization step. Hydroterminate is typically carried out at temperatures in the range of about 190 ° C to about 340 ° C, at pressures of about 400 psig to about 3000 psig, at space speeds (LHSV) of about 0.1 to about 20, and speeds of hydrogen recirculation from about 400 to about 1500 SCF / bbl.

The hydrogenation catalyst employed must be sufficiently active not only to hydrogenate the olefins and diolefins within the lubricating oil fractions, but also to reduce the content of any aromatic present.

Suitable hydrogenation catalysts include conventional metal hydrogenation catalysts, particularly Group VIII metals such as cobalt, nickel, palladium and platinum. The metals are typically associated with vehicles such as bauxite, alumina, silica gel, silica-alumina compounds and crystalline aluminosilicate zeolites and other molecular sieves. Palladium is a particularly preferred hydrogenation metal. If desired, non-noble Group VIII metals can be used with molybdenum. Metal oxides or sulfides can be used. Suitable catalysts are described in Pats. U.S. Nos. 3,852,207; 4,157,294; 4,921,594; 3,904,513 and 4,673,487, the descriptions of which are incorporated herein by reference.

SAW. DETAILED DESCRIPTION OF THE DRAWING Figure 1 represents a simplified schematic flow chart of one embodiment of the process of the invention. The feed material stream of the lubricating oil 5 and the hydrogen stream 10 are passed to the catalytic dewaxing unit 15, e.g., an ISODEWAXING catalytic dewaxing unit. The effluent 20 from the catalytic dewaxing unit 15 is passed to the hydrofoil unit 25. The effluent 30 from the hydroterminate unit 25 is passed to the distillation column at atmospheric pressure for the initial fractionation. Various streams of products, eg, light gas streams 36, naphtha stream 37, fuel stream for combustion turbines 38 and bottom stream 40, are removed from the distillation column at atmospheric pressure 35. The bottoms stream 40 the atmospheric distillation column 35 is passed to the vacuum distillation column for further fractionation. Various streams of products, eg, the diesel fuel stream 50, the neutral oil stream 55, the neutral oil stream 100 and the bottom stream (or the neutral oil 300) 65, are removed from the distillation column to vacuum 45. A portion of the bottom stream 65 is removed as the neutral oil stream 70 and a portion is recirculated through the stream 75 to mix with the stream of the lubricating oil feed material 5.

VII. ILLUSTRATIVE MODALITIES The invention will be better clarified by the following examples, which are intended to be purely exemplary of the invention.

The benefits of the recirculation operation of the fractionator funds have been demonstrated in the large-scale pilot plant test. For the demonstration run, the reactor of s i n f i na t ion contained approximately 5,000 ce of a SAPO catalyst impregnated with precious metal and the hydroterminate reactor contained approximately 5,000 ce of a hydrocarbon catalyst from the Chevron property. In the distillation line produced 3 cuts of lubricant plus a cut of middle distillate. The pilot plant was configured to stimulate the flow scheme illustrated in Figure 1.

Two widely boiled hydrotherm-fractionated feed materials were tested. Inspections for these feedstocks are shown in Table 6. After isodesparaffinization and hydrofinishing, the fully liquid product was fractionated into 3 finished base oil cuts - a neutral oil 60, a neutral oil 100 and a neutral oil 300. Table 7 summarizes the improvements developed by recirculating a portion of the fractionator funds.

For tests 1, the fresh feed rate remained approximately constant, while the percent recirculation of the fractionator bottoms and the average heavy bed temperature of the buffer evaporator (WAT) were varied. The hydrotherminator was operated at approximately constant temperature during these runs.

Comparing Test 1 and Test 2 shows that when a large proportion of fractionator funds are recirculated, it is possible to reduce the WAT of isodesparaffin and, although, the severity of the dewaxing is not completely the same in both cases, it dramatically increases the total lubricant performance - from 70% to 80%. The recirculation also moves the points of the critical flow temperature of 100N and 300N much closer - the difference between the points of the critical flow temperature is 18 ° C in Test 2", but only 9 ° C in Test 1 This means that with the recirculation, 100N does not have to be over dewaxed enough to make a point of acceptable critical fluidity temperature in the 300N B. Test 3 was run at the same point of critical flow temperature 300N as Test 2. With recirculation (Test 3), we were able to increase the overall lubricant performance to 3%, and increase the performance of the temperature point of critical lower fluidity, high value, 100N by 4%. Again, with recirculation, the degree of over-deparaffination of the 100N is reduced.

C. Test 4 was run at the same temperature of the heavy average bed of the solvator as in Test 2, but in Test 4, the bottoms of fractionator 13 contained the isodesparaffinator feed (recirculation). Although the total lubricant performance is the same, in Test 4, there is 2% less 300N and 2% plus 60N. More importantly, in Test 4, the points of the critical flow temperature of the fractions of the finished lubricant are substantially lower. In this way, recirculation can improve the product properties of the finished lubricants without changing the overall performance.

For Tests 5 to 7, the fresh feed rate, as well as the percent of the fractionator were varied. Again, the hydrotherminator was operated at approximately constant temperature.

A. For Test 6, the fresh feed rate was increased to 23% without any recirculation. To maintain the same point of approximate flow temperature at 300N, the WAT of the isodesparaffinator had to be increased by 5 ° F, but in this case (without recirculation), the overall lubricant performance remained the same, while the points of the Fluid temperature of the lubricant fractions increased slightly (the worst obtained).

B. For Test 7, the fresh feed rate was essentially maintained and the fractionator bottoms contained 14% isodesparaffinator feed. In this case, we were able to slightly decrease the temperature of the isodesparaffinizer catalyst, while remaining close to the same points of the critical flow temperature, and it was observed that the total lubricant yield increased 2%. Perhaps more importantly, the 100N efficiency increased to 4% while the 100N critical fluidity point dropped slightly.

The above comparative examples show the unexpected improved development when a portion of the fractionator bottoms is recirculated. Due to the increase in the amount of recirculation of funds, the amount of the fresh feed that can be processed will eventually be limited, the economic limits will usually dictate the maximum amount of recirculation.

Table 6 PILOT PROOF FEEDING MATERIALS Food Feeding PROPERTIES PARAFINICAS gravity API 35.9 33.7 Nitrogen ppm 1.6 1.3 Sulfur, ppm 7.3 6.3 Aroma 6.0% 7.7 Viscosity, cSt @ 65C 9.110 11.766 100C 4.24 5.137 VI paraffinic 121 118 Pour point 39 39 critical, ° C Content of 22.96 18.09 paraffin,% weight Distillation, ° F 10% 640 678 50% 787 819 90% 960 970 DEPARAFINATED OIL WITH SOLVENT Viscosity, cSt @ 40C 21.418 30.327 100C 4,306 5,309 VI 107 108 pour point -18 -21 review, ° C Table 7 Summary of the Pilot Plant No. LHSV power of IDW% Point of yield point of the oil feed recirculation test W.A.T. Fluency Lubricant fluidity corrected, * total supply • r 100N, ° C 300N, ° C 60N 100N 300N Total to reactor 1 Power A 1.39 37 683 -18 -9 27 39 14 80 2 Power A 1.03 0 700 -31 -13 24 31 15 70 3 Feeding A 1.18 15 696 -28 -13 24 35 14 73 L? or 4 Power A 1.17 13 700 -33 -18 28 31 13 70 10 5 Power supply B 1.00 0 694 -27 -11 17 39 25 81 6 Power supply B 1.23 0 699 -25 -10 18 40 23 81 7 Power supply B 1.11 14 689 - 30 -9 19 44 20 83 fifteen It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following is claimed as property.

Claims (42)

1. A process for converting a hydrocarbon oil, characterized in that it comprises: (a) contacting a hydrocarbon oil feedstock in the presence of hydrogen gas added with a catalyst system comprising a molecular sieve of siloaluminophos fat or intermediate pore size and a hydrogenation component, wherein at least a portion of the feed material is converted; (b) passing at least a portion of the converted feedstock to a fractionator, wherein at least a portion of the feed material converted is fractionated, whereby at least a head fraction and a fraction of bottoms are produced; Y (c) mixing at least a portion of the bottom fraction with the hydrocarbon oil feedstock in step (a).

2. The process of claim 1, characterized in that the catalyst is selected from the group consisting of SAPO-11, SAPO-31 or SAPO-41.

3. The process of claim 1, characterized in that the catalyst further comprises a catalyst selected from the group consisting of an intermediate pore size aluminosilicate zeolite catalyst, an amorphous catalyst and mixtures thereof.

4. The process of claim 2, characterized in that the sieve of coaluminophosphthoate comprises SAPO-11 and the hydrogenation component comprises platinum.

5. The process of claim 4, characterized in that the catalyst system consists essentially of an SAPO-11.

6. The process of claim 1, characterized in that the component is present in an amount from about 0.01% to about 10% based on the weight of the molecular sieve.

7. The process of claim 2, characterized in that the catalyst system further comprises an aluminosilicate zeolite catalyst of intermediate pore size and is predominantly in the hydrogen form.

8. The process of claim 7, characterized in that the catalyst further comprises a hydrogenation component.

9. The process of re-indication 8, characterized in that the hydrogenation component comprises a Group VIII metal.

10. The process of claim 9, characterized in that the hydrogenation component is selected from platinum, palladium and mixtures thereof.

11. The process of claim 7, characterized in that the pore size aluminosilicate zeolite has a coaction index measured from about 400 ° C to about 454 ° C from about 4 to about 12.

12. The process of claim 7, characterized in that the intermediate pore size aluminosilicate zeolite is selected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM -48 and mixtures thereof.

13. The process of claim 7, characterized in that the intermediate pore size aluminosilicate zeolite catalyst further comprises a metal selected from Group VIII metals consisting of platinum, palladium and nickel and mixtures thereof or metals of Group VIB which It consists of molybdenum, chromium, tungsten and mixtures thereof.

14. The process of re-indication 7, characterized in that the weight ratio of the molecular sieve of silylaluminophos fat or pore size intermediate to the molecular sieve of intermediate pore size silanoaluminophosphate zeolite is from about 1: 5 to about 20: 1.

15. The process of claim 1, characterized in that the process is a dewaxing process and where it is brought into contact under dewaxing conditions.

16. The process of claim 15, characterized in that the contacting is carried out at a temperature of about 200 ° C to 475 ° C, a pressure of about 15 psig to about 3000 psig, a space velocity per hour of liquid of about 0.1 hr "1 to about 20 hr ** 1, and a hydrogen circulation rate of 500 to about 30,000 SCF / bbl.

17. The process of claim 15, characterized in that the amount of the bottoms of the fractionator mixed with the hydrocarbon oil feedstock is an effective amount to increase the yield of the converted feedstock or reduce the point of the critical flow temperature of the Converted feed material.

18. The process of claim 17, characterized in that from about 1 weight percent to about 80 weight percent of the bottoms of the fractionator is mixed with the hydrocarbon oil feed material.

19. The process of claim 15, characterized in that the weight ratio of the fractionator bottoms mixed with the hydrocarbon oil feed material to the hydrocarbon oil feed material is an effective ratio to increase the yield of the converted feed material. or reduce the point of the critical flow temperature of the converted feed material.

20. The process of claim 19, characterized in that the weight ratio of the fractionator bottoms mixed with the hydrocarbon oil feedstock to the hydrocarbon oil feedstock is from about 1: 100 to about 60: 100.

21. The process of claim 1, characterized in that the hydrocarbon oil feedstock is a medium distillate oil.

22. The process of claim 22, characterized in that the feedstock 'is a lubricating oil feedstock.

23. The process of claim 22, characterized in that the hydrocarbon oil feedstock contains less than 50 pppm of organic nitrogen.

24. The process of claim 23, characterized in that the hydrocarbon oil feedstock contains less than 10 pppm of organic nitrogen.

25. The process of claim 1, characterized in that the hydrocarbon oil feedstock is paraffinic gloss material.

26. The process of claim 1, characterized in that the hydrocarbon oil feedstock comprises a refining of the lubricating oil range and wherein the process is a process for hydrodesin to refine the raffinate, which comprises contacting the raffinate in the presence of hydrogen added under hydrodefinition conditions with the catalyst system.

27. The process of claim 1, characterized in that the hydrocarbon oil feedstock comprises a paraffinic hydrocarbon feed and wherein the process is a process to improve the viscosity index, relative to conventional solvent dewaxing, of a product dewatering of the paraffinic hydrocarbon feed comprising contacting the catalyst with the paraffinic hydrocarbon feed under dewaxing conditions by isomerization.

28. The process of claim 1, characterized in that at least a major portion of the hydrocarbon oil feedstock, boils above about 350 ° F and contains straight chain and slightly branched chain hydrocarbons, and wherein the process is a process for catalytically dewaxing the boiling hydrocarbon oil feed above about 350 ° F, and containing straight chain and slightly branched chain hydrocarbons comprising contacting the hydrocarbon oil feedstock in the presence of hydrogen gas added at a hydrogen pressure of about 15-3000 psi under dewaxing conditions with the catalyst system.

29. The process of claim 1, characterized in that the process is a process for preparing a lubricating oil: (a) wherein the hydrocarbon oil feedstock of the hydrotherm fractionation in a hydro-thermo-reaction zone, a hydrocarbon feedstock to obtain an effluent comprising a hydrotherm-fractionated oil; Y (b) wherein the step of contacting comprises catalytically dewaxing the effluent at a temperature of at least about 200 ° C and at a pressure of about 15 psig to about 3000 psig in the presence of hydrogen gas added with the catalyst.

30. A process for dewaxing a hydrocarbon oil, characterized in that it comprises: (a) contacting, under dewaxing conditions, a lubricating oil feedstock in the presence of hydrogen gas added with a catalyst system comprising a molecular sieve of silylaluminophos fat or intermediate pore size and a hydrogenation component, wherein the hydrogenation component is present in an amount from about 0.01% to about 10% d on the weight of the molecular sieve of silicoaluminophosphate, and comprising a catalyst selected from the group consisting of a zeolite, an amorphous catalyst and mixtures thereof, wherein at least a portion of the feedstock is dewaxed; (b) passing at least a portion of the feed material to a fractionator, wherein at least a portion of the dewatered feed material is fractionated, whereby at least a head fraction and a fraction of bottoms are produced; Y (c) mixing at least one effective amount to increase the yield or reduce the point of the critical flow temperature of the dewaxed feedstock of the bottom fraction with the hydrocarbon oil feedstock in step (a).

31. The process of claim 30, characterized in that the molecular sieve of silicoaluminophosphate comprises SAPO-11 and the hydrogenation component comprises platinum.

32. The process of claim 31, characterized in that the molecular sieve of silicoaluminof osf ato consists essentially of a SAPO-11.

33. The process of claim 30, characterized in that the aluminosilicate zeolite catalyst further comprises a Group VIII metal hydrogenation component.

34. The process of claim 33, characterized in that the intermediate pore size aluminosilicate zeolite is selected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM -48 and mixtures thereof.

35. The process of claim 30, characterized in that the weight ratio of the molecular sieve of si 1 i intermediate pore size coaluminophosphate to the molecular sieve of intermediate pore size silicoaluminophosphate zeolite is from about 1: 5 to about 20: 1.

36. The process of claim 30, characterized in that the process is a dewaxing process and where it is brought into contact under dewaxing conditions.

37. The process of claim 36, characterized in that the contacting is carried out at a temperature of about 200 ° C to 475 ° C, a pressure of about 15 psig to about 3000 psig, a space velocity per hour of liquid of about 0.1 hr "1 to about 20 hr" 1, and a hydrogen circulation rate of 500 to about 30,000 SCF / bbl.

38. The process of claim 30, characterized in that from about 1 weight percent to about 80 weight percent of the bottoms of the fractionator is mixed with the hydrocarbon oil feed material.

39. The process of claim 38, characterized in that the weight ratio of the bottoms of the fractionator mixed with the hydrocarbon oil feedstock to the hydrocarbon oil feedstock is from about 1: 100 to about 60: 100.

40. The re-indication process 30, characterized in that the hydrocarbon oil feedstock is a medium distillate oil.

41. The process of claim 30, characterized in that the hydrocarbon oil feedstock contains less than 50 pppm of organic nitrogen.

42. A process for dewaxing a hydrocarbon oil, characterized in that it comprises: (a) contacting, at a temperature of about 200 ° C to 475 ° C, a pressure of about 15 psig to about 3000 psig, a space velocity per hour of liquid of about 0.1 hr "1 to about 20 hr" 1 and a hydrogen circulation rate of 500 to about 30,000 SCF / bbl., a lubricating oil feedstock containing less than 500 pppm of organic nitrogen, in the presence of 10 hydrogen gas added, with catalysts consisting essentially of a molecular sieve of silicoaluminophosphate of intermediate pore size of SAPO-11 and a hydrogenation component, wherein the The hydrogenation component is present in an amount of about 0.01% to about 10% based on the weight of the molecular sieve of silicoaluminophos or fat, and a zeolitic catalyst of SSZ-32 which 20 contains a Group VIII metal hydrogenation component, wherein the weight ratio of SAPO-11 to SSZ-32 is from about 1: 5 to about 20: 1, wherein at least one The portion of the feed material is dewaxed; (b) passing at least a portion of the feed material to a fractionator, wherein at least a portion of the dewaxed feed material is fractionated, whereby at least a head fraction and a fraction of bottoms are produced; Y (c) mixing from about 1 weight percent to about 80 weight percent of the dewaxed feed material of the bottom fraction with the hydrocarbon oil feedstock in step (a).