JP4796508B2 - Hydroisomerization using sulfurized catalyst - Google Patents

Description

  This application is related to US patent application Ser. No. 10 / 747,152 (Docket No. 005950-826) filed under the title “Hydroisomerization Process Using Pre-Sulfided Catalysts”. Which is incorporated herein by reference in its entirety.

  The present invention relates generally to the production of a Fischer-Tropsch derived lubricating base oil. More specifically, the present invention uses a sulfurized shape-selective medium pore size noble metal-containing molecular sieve catalyst to produce a lubricating base oil having a high viscosity index and a low pour point in high yield. Is targeted.

  Refining operations that produce large quantities of high quality lubricating base oils are desirable. There is an increasing demand placed on refiners for the production of high-quality lubricating base oils in the operation of modern machines and automobiles. Many refining processes tend to produce light grade products in large quantities at the expense of producing lubricating base oil products.

  It is well known in the art to produce lubricating base oils using hydroisomerization processes. For example, US Pat. Nos. 5,135,638 and 5,082,986 disclose highly shape selective catalysts for hydroisomerizing waxy feedstocks. US Pat. No. 5,135,638 improves the isomerization selectivity by lowering the hydroisomerization dewaxing and reducing the liquid hourly space velocity, which results in more feedstock. It is disclosed that it will isomerize and decompose less, thereby improving yields. Thus, US Pat. No. 5,135,638 discloses that the yield of the resulting lubricating base oil product can be improved by lowering the pressure when carrying out the hydroisomerization process.

  It is also well known in the art to use base metal catalysts and noble metal catalysts for hydroisomerization processes. These catalysts can be used on molecular sieve supports. As an example, US Pat. No. 5,885,438 describes the catalytic dewaxing of waxy paraffins present in the feedstock by isomerization in the presence of hydrogen and in the presence of a low acidity large pore zeolite isomerization catalyst. A method of producing a high viscosity index lubricant from a waxy hydrocarbon feedstock is disclosed. The catalyst of US Pat. No. 5,885,438 includes a noble metal hydroisomerization catalyst such as Pt. US Pat. No. 5,885,438 further discloses that platinum or palladium catalysts have good hydrogenation activity, but only in the absence of sulfur.

  There remains a need for an effective and efficient process for producing high yields of high quality lubricating base oils from waxy hydrocarbon feedstocks.

  Embodiments of the present invention are directed to a method of producing a high yield of lubricating base oil from a waxy hydrocarbon feedstock. In one embodiment, the method includes sulfiding a shape selective medium pore size noble metal-containing molecular sieve catalyst during operation to provide a sulfided catalyst. To produce a lubricating base oil, the waxy hydrocarbon feedstock is hydroisomerized by contacting it with the sulfurized catalyst under hydroisomerization conditions. This sulfurized catalyst can optionally be resulfurized.

  In other embodiments, the method includes presulfiding a shape selective medium pore size noble metal-containing molecular sieve catalyst to provide a sulfurized catalyst. This waxy hydrocarbon feed is contacted with a sulfided catalyst at hydroisomerization conditions. This sulfurized catalyst is resulfurized. A lubricating base oil is isolated.

  According to the method of the present invention, surprisingly, the selectivity of hydroisomerization over hydrocracking is improved by sulfiding the shape selective medium pore noble metal containing molecular sieve catalyst, thereby producing It has been found that the yield of lubricating base oil is increased. Thus, contacting a waxy hydrocarbon feedstock with a sulfurized shape selective medium pore noble metal-containing molecular sieve catalyst provides a high yield of high quality lubricating base oil.

Catalyst sulfidation When the catalyst was sulfidized, it was found that the hydroselectivity of the shape-selective mesoporous noble metal-containing molecular sieve catalyst was improved (the isomerization reaction has priority over the decomposition reaction). . According to the present invention, the catalyst can be sulfided prior to or during the hydroisomerization reaction. A noble metal is any metal that is resistant to corrosion or oxidation. A catalyst containing a noble metal is any catalyst containing a noble metal. Precious metal catalysts include platinum, palladium, and mixtures thereof.

  According to the present invention, this shape selective medium pore noble metal-containing molecular sieve catalyst for carrying out the hydroisomerization process is sulfurized. This catalyst can be sulfided at various stages during the hydroisomerization process. This catalyst may be sulfided prior to the hydroisomerization reaction. According to the present invention, the sulfiding process is referred to as “pre-sulfiding” of the catalyst if it is carried out before introducing the waxy feed into the reactor in which the hydroisomerization process is carried out. If performed after the hydroisomerization reaction has been initiated, the sulfidation process is referred to as “operational sulfidation”. This in-operation sulfidation process can be carried out simultaneously with the hydroisomerization process using a feedstock for the hydroisomerization process that contains sulfur required for sulfidation. Alternatively, this in-service sulfidation process may be carried out by pausing the hydroisomerization reaction step, sulfiding the catalyst, and then restarting the hydroisomerization reaction step. When the hydroisomerization process is halted, the sulfidation of the catalyst can be performed by the same technique used for presulfiding the catalyst. If a catalyst that was first pre-sulfided or previously sulfided in the step of sulfiding during operation is then subjected again to the sulfidation process, the sulfidation process is referred to as “resulfurization”. This resulfurization can be carried out simultaneously with the hydroisomerization process or by suspending the hydroisomerization process as described above for in-service sulfidation. According to the invention, the catalyst is preferably presulfided.

  According to the present invention, the sulfiding of the shape selective medium pore size noble metal-containing molecular sieve catalyst can be carried out by techniques for sulfiding catalysts known to those skilled in the art. As an example, the catalyst can be sulfided by contacting the catalyst with a sulfur-containing species, usually in the presence of hydrogen. Mixtures of hydrogen and mercaptans such as hydrogen sulfide, carbon disulfide or butyl mercaptan are usually used for sulfiding. Sulfurization can be performed by contacting the catalyst with hydrogen and a sulfur-containing hydrocarbon oil such as acid kerosene or gas oil (referred to as non-reinforced feedstock) or by adding active sulfur to the waxy hydrocarbon feedstock. (Referred to as sulfur-enriched feedstock).

Specifically, presulfiding can be performed by techniques well known to those skilled in the art. Procedures have been developed by those skilled in the art to presulfide new catalyst charges for a fixed bed reactor system at each start of operation in situ. These procedures usually involve wetting / immersing the catalyst in the starter oil, followed by a gas heating step and a catalyst drying step, followed by a non-spiked feedstock (natural origin). Sulfurization in a step using a sulfur-containing feedstock), or a sulfur-enriched feedstock (a feedstock to which an active sulfur compound has been added). Alternatively, this sulfidation step can use H ₂ / H ₂ S to sulfidize the catalyst in the gas phase. Exemplary sulfidation techniques known in the art were discussed by Harman Hallie at the Amsterdam catalyst symposium in May 1982 and published in the publication of Oil and Gas Journal on December 20, 1982. . Other descriptions are described in William J .; It can be found in the paper entitled “Properties and Applications of Commercial Presulding Agents” published by Tuzynski at the 1989 NPRA conference.

  According to an embodiment of the present invention, the sulfiding of the catalyst includes adding at least 1 mole of sulfur per mole of noble metal, preferably platinum and / or palladium, contained in the catalyst. This noble metal is dispersed in a shape selective medium pore size noble metal-containing molecular sieve catalyst. Those skilled in the art will appreciate that the number of moles of metal in the catalyst is calculated by calculating the number of grams of catalyst multiplied by the metal weight percent divided by the molecular weight of the metal. In a preferred embodiment, the molar ratio of sulfur to noble metal is at least 3: 1. In one example of this embodiment, sufficient sulfur addition in the presulfidation step results in a sulfur to noble metal molar ratio of at least 2: 1. During the course of the hydroisomerization process, the addition of additional sulfur to the catalyst results in a sulfur to noble metal molar ratio of at least 3: 1. In other embodiments, the ratio is 5: 1.

In general, presulfidation techniques using unreinforced feedstocks involve the decomposition of sulfur compounds to H ₂ S, where the sulfur compounds are naturally present in the selected starting hydrocarbon feed. The reactor temperature for these techniques is generally in the range of about 300-350 ° C (572-662 ° F). In contrast, presulfidation techniques using fortified feeds can be performed by injecting active sulfur-containing organic compounds into selected starting hydrocarbon feeds, where the injected compounds are natural Decomposes to H ₂ S at a temperature below that required to decompose the originating sulfur compound (if present). Preferred tougheners are dimethyl sulfide and dimethyl disulfide because these compounds allow the sulfurization procedure to be performed at temperatures in the range of about 250-275 ° C.

  The presulfidation and start-up approach maintains the reactor quality conditions so that the original quality of the waxy hydrocarbon feedstock and the sulfurization and hydrogenation reactions do not create deleterious temperature conditions inside the catalyst pellets. To be adjusted. These deleterious temperature conditions can result in carbon deposition or metal sintering, both of which reduce catalyst activity and are therefore undesirable. The intensity of the hydrogenation reaction that occurs during the initial catalyst conditioning and sulfidation period is limited by the quality of the initial waxy hydrocarbon feed (eg, sulfur content) and reactor temperature, which attenuates the sulfidation reaction. Or until it essentially stops. State-of-the-art technology allows in-situ presulfidation to be initiated at temperatures below about 200 ° C. (392 ° F.) and completed before the temperature exceeds about 300 ° C. (572 ° F.).

  Techniques are known for pretreating a catalyst by impregnating it with a sulfur compound (eg, a polysulfide as described in US Pat. No. 5,786,293) prior to charging the catalyst into the reactor. This is called ex situ presulfidation. When using ex-situ presulfidation, the catalyst may need to undergo further drying, wetting and conversion to metal sulfides in situ in the reactor during the startup procedure. An economical method for presulfiding a new batch of catalyst added to an operating reactor operated at high temperature and hydrogen pressure ex situ is disclosed in US Patent Application No. 2002/0043483, which The entirety of which is incorporated herein by reference.

Waxy hydrocarbon feedstocks Useful feedstocks for the hydroisomerization process according to the present invention include gas oils, lubricating oil feedstocks, synthetic oils, Fischer-Tropsch derived olefins, oligomerized Fischer-Tropsch derived olefins, waxy bottom oil Waxy hydrocarbons, including crude waxes, deoiled waxes, linear alpha-olefin waxes, microcrystalline waxes, and mixtures thereof. Preferred feedstocks are Fischer-Tropsch derived wax, crude wax, deoiled wax, linear alpha-olefin wax, and oligomerized Fischer-Tropsch derived olefin. A particularly preferred feedstock is a Fischer-Tropsch derived wax.

  In some embodiments of the present invention, it is desirable to use a waxy hydrocarbon feed containing less than 10 ppm sulfur. Thus, a waxy hydrocarbon feed containing high concentrations of sulfur (greater than 10 ppm) is preferably hydrotreated prior to the hydroisomerization reaction to remove sulfur. Accordingly, a waxy hydrocarbon feedstock having a low content of sulfur, preferably less than 10 ppm sulfur, is preferred. These low sulfur feedstocks include Fischer-Tropsch derived waxes, oligomerized Fischer-Tropsch derived olefins, linear alpha-olefin waxes, and hydrotreated crude waxes derived from feedstocks.

  The waxy hydrocarbon feedstock contains at least 10% by weight wax, often more than 50% by weight wax, often more than 80% by weight.

Fischer-Tropsch Synthesis The waxy hydrocarbon feedstock of the present invention is preferably derived from a Fischer-Tropsch waxy feedstock.

  In a Fischer-Tropsch chemical reaction, synthesis gas is converted to a liquid hydrocarbon by contacting it with a Fischer-Tropsch catalyst under highly reactive conditions. Typically, methane and optionally heavier hydrocarbons (ethane and heavier) can be sent by a conventional syngas generator to supply synthesis gas. In general, synthesis gas contains hydrogen and carbon monoxide and may contain small amounts of carbon dioxide and / or water. The presence of sulfur, nitrogen, halogen, selenium, phosphorus and arsenic contaminants in the synthesis gas is undesirable. For these reasons, depending on the quality of the synthesis gas, it is preferable to remove sulfur and other contaminants before performing the Fischer-Tropsch chemistry. Means for removing these contaminants are well known to those skilled in the art. For example, a ZnO guard bed is preferred for removing sulfur impurities. Means for removing other contaminants are well known to those skilled in the art. It is also desirable to purify the synthesis gas prior to the Fischer-Tropsch reactor to remove the carbon dioxide produced during the synthesis gas reaction and any additional sulfur compounds that were not previously removed. This can be done, for example, by contacting the synthesis gas with a mild alkaline solution (eg, aqueous potassium carbonate) in a packed column.

In the Fischer-Tropsch process, liquid and gaseous hydrocarbons are obtained by contacting a synthesis gas containing a mixture of H ₂ and CO with a Fischer-Tropsch catalyst under conditions of high reactivity at an appropriate temperature and pressure. It is formed. Fischer-Tropsch reactions are typically at temperatures of about 300-700 ° F (149-371 ° C), preferably about 400-550 ° F (204-228 ° C); about 10-600 pounds per square inch. Absolute (0.7-41 bar), preferably about 30-300 pounds per square inch absolute (2-21 bar) pressure; about 100-10000 cc / g / hour, preferably about 300-3000 cc / g / hour Of the catalyst space velocity. Examples of conditions for carrying out a Fischer-Tropsch type reaction are well known to those skilled in the art.

Fischer-Tropsch synthesis products are in the C ₁ -C ₂₀₀₊ range, most of which are in the C ₅ -C ₁₀₀₊ range. This reaction can be carried out in various reactor types, such as a fixed bed reactor with one or more catalyst beds, a slurry reactor, a fluidized bed reactor, or a combination of different types of reactors. Such reaction methods and reactors are well known and documented in the literature.

  The preferred slurry Fischer-Tropsch process for the practice of the present invention utilizes excellent heat (and mass) transfer characteristics for a strongly exothermic synthesis reaction and, when a cobalt catalyst is used, a relatively high molecular weight paraffinic system. Hydrocarbons can be produced. In the slurry process, synthesis gas containing a mixture of hydrogen and carbon monoxide is dispersed and suspended as a third phase in a slurry liquid containing a hydrocarbon product of the synthesis reaction that is liquid under the reaction conditions. Up through a slurry containing a granular Fischer-Tropsch type hydrocarbon synthesis catalyst. The molar ratio of hydrogen to carbon monoxide ranges from about 0.5 to about 4, but more typically from about 0.7 to about 2.75, preferably from about 0.7 to about 2. Within the range of 5. A particularly preferred Fischer-Tropsch process is taught in EP0609079, which is hereby fully incorporated by reference for all purposes.

In general, Fischer-Tropsch catalysts contain a Group VIII transition metal supported on a metal oxide support. The catalyst can also include noble metal promoter (s) and / or crystalline molecular sieves. Suitable Fischer-Tropsch catalysts include one or more of Fe, Ni, Co, Ru and Re, with cobalt being preferred. Preferred Fischer-Tropsch catalysts are effective amounts of cobalt and one or more Re, Ru, Pt supported on a suitable inorganic support material, preferably one comprising one or more refractory metal oxides. Fe, Ni, Th, Zr, Hf, U, Mg, and La. Generally, the amount of cobalt present in the catalyst is between about 1 and about 50 weight percent of the total catalyst composition. This catalyst also includes basic oxide promoters such as ThO ₂ , La ₂ O ₃ , MgO, and TiO ₂ , promoters such as ZrO ₂ , noble metals (Pt, Pd, Ru, Rh, Os, Ir), coins It can contain metals (Cu, Ag, Au) and other transition metals such as Fe, Mn, Ni, and Re. Suitable carrier materials include alumina, silica, magnesia and titania or mixtures thereof. A preferred support for the cobalt containing catalyst comprises titania. Useful catalysts and their preparations are known and illustrated in US Pat. No. 4,568,663, which is illustrative and non-limiting in connection with catalyst selection. .

Certain catalysts provide a relatively low to moderate chain growth probability, and the reaction product has a relatively high proportion of low molecular weight (C _2-8 ) olefins and a relatively low proportion of high molecular weight ( C ₃₀₊ ) wax is known to contain. Certain other catalysts provide a relatively high chain growth probability, and the reaction product has a relatively low proportion of low molecular weight (C _2-8 ) olefins and a relatively high proportion of high molecular weight (C ₃₀₊ ). It is known to contain wax. Such catalysts are well known to those skilled in the art and can be readily obtained and / or prepared.

The product from the Fischer-Tropsch process contains mainly paraffin. The products from the Fischer-Tropsch reaction generally include light and waxy reaction products. This light reaction product (ie, the condensate fraction) boils below about 700 ° F. (eg, from tail gas to middle distillate fuel) and includes an amount that gradually decreases until about C ₃₀ is reached. mainly comprising hydrocarbons ranging from _C 5 _{-C 20.} This waxy reaction product will boil above about 600 ° F. (eg, from vacuum gas oil to heavy paraffin), and will contain decreasing amounts until it reaches C ₁₀ , mainly C ₂₀₊ . Includes a range of hydrocarbons.

  Both the light reaction product and the waxy product are substantially paraffinic. The waxy product generally contains more than 70 weight percent linear paraffins, often more than 80 weight percent linear paraffins. This light reaction product comprises a paraffinic product containing a significant proportion of alcohol and olefin. In some cases, the light reaction product may contain 50 weight percent, and even more alcohol and olefin. The waxy reaction product (ie, wax fraction) is used as the feedstock for the process of the present invention.

  According to the present invention, a lubricating base oil can be prepared by hydroisomerizing a waxy Fischer-Tropsch reaction product. Other methods that can be used to prepare lubricating base oils from waxy Fischer-Tropsch reaction products include hydrotreating, oligomerization, solvent dewaxing, atmospheric and vacuum distillation, hydrocracking, hydrofinishing, and others There is a hydroprocessing method of the form.

Hydroisomerization According to the present invention, the waxy hydrocarbon feedstock is subjected to a hydroisomerization process using a sulfurized shape selective medium pore noble metal-containing molecular sieve catalyst. Hydroisomerization is intended to improve the low temperature fluidity of lubricating base oils by the selective addition of branches to the molecular structure. Hydroisomerization ideally achieves high conversion of waxy hydrocarbon feed to non-wax-like iso-paraffins with minimal conversion by cracking.

  According to the present invention, hydroisomerization is carried out using a shape selective medium pore noble metal-containing molecular sieve catalyst. As used herein, the phrase “medium pore size” means an effective pore size in the range of about 4.0 to 7.1 inches when the porous inorganic oxide is calcined. The shape selective medium pore size molecular sieves used in the practice of this invention are generally 1-D 10, 11 or 12 membered molecular sieves. The preferred molecular sieve of the present invention is a 1-D 10-membered ring variety, provided that the 10 (or 11 or 12) membered molecular sieve is 10 (or 11 or 12) tetrahedral bonded by oxygen. It has a body coordination atom (T atom). In 1-D molecular sieves, 10-membered ring (or larger) pores are parallel to each other and do not connect to each other. The classification of intra-zeolite channels as 1-D, 2-D and 3-D is described in R.A. M.M. Barrer, Zeolite, Science and Technology, F.M. R. Rodrigues, L. D. Rollman and C.I. Edited by Naccache, NATO ASI Series, 1984, this classification is incorporated by reference in its entirety (see especially page 75).

  The shape-selective medium pore noble metal-containing molecular sieve catalyst according to the present invention may be a zeolitic molecular sieve, a non-zeolitic molecular sieve, or a mixture thereof. Preferably, the shape selective medium pore noble metal-containing molecular sieve catalyst is non-zeolitic.

As used herein, a non-zeolitic molecular sieve is a crystal of one or more metals in tetrahedral coordination with tetrahedrally bound A1O ₂ and PO ₂ oxide units and, optionally, oxygen atoms. This means a molecular sieve containing a three-dimensional microporous skeleton structure. Preferably, the non-zeolitic molecular sieve is an anhydrous basis unit empirical formula
(M _x A _y P _z ) O ₂
[Wherein “M” represents at least one element other than aluminum and phosphorus, which forms a tetrahedrally coordinated oxide with AlO ₂ and PO ₂ oxide structural units in a crystalline molecular sieve. Is possible;
“X”, “y”, and “z” represent the molar fractions of the elements “M”, aluminum, and phosphorus, respectively, where “x” is greater than or equal to zero (0), “y”, and “z”. Are each characterized by a three-dimensional microporous network of AlO ₂ having a value of at least 0.01 and PO ₂ tetrahedral oxide units.

  In a preferred embodiment, the metal element “M” is selected from the group consisting of arsenic, beryllium, boron, chromium, cobalt, gallium, germanium, iron, lithium, magnesium, manganese, silicon, titanium, vanadium, nickel, and zinc; More preferably selected from the group consisting of silicon, magnesium, manganese, zinc, and cobalt; even more preferably selected from silicon. In this specification, the element “M” is regarded as a component of the non-zeolitic molecular sieve.

  According to the present invention, the preferred shape selective medium pore size molecular sieve used for hydroisomerization is a non-zeolitic molecular sieve. Preferred shape selective medium pore size non-zeolitic molecular sieves are based on aluminum phosphates (ie, SAPO catalysts) such as SAPO-11, SAPO-31, and SAPO-41, with SAPO-11 and SAPO-31 being more preferred. SAPO-11 is more preferable. SM-3 is a preferred shape-selective medium pore size SAPO, which corresponds to the crystal structure of SAPO-11 molecular sieve. The preparation of SM-3 and its unique properties are described in US Pat. Nos. 4,943,424 and 5,158,665.

  In other embodiments of the invention, zeolitic molecular sieves can be used. These include ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, SSZ-32, orthopyroxene, and ferrierite, with SSZ-32 and ZSM-23 being preferred.

  Preferred mesopore molecular sieves are characterized by the crystallographic free diameter of the selected channel, the selected crystallite size (corresponding to the selected channel length), and the selected acidity. The desired crystallographic free diameter of the molecular sieve channel is about 4.0 to 7.1 mm with a maximum crystallographic free diameter of 7.1 or less and a minimum crystallographic free diameter of 3.9 mm or more. Is in range. Preferably, the maximum crystallographic free diameter is 7.1 or less and the minimum crystallographic free diameter is 4.0 or more. Most preferably, the maximum crystallographic free diameter is not more than 6.5 and the minimum crystallographic free diameter is not less than 4.0 mm. The crystallographic free diameter of the channels of molecular sieves is described in “Atlas of Zeolite Framework Types”, 5th revised edition, 2001, Ch. Baerlocher, W.M. M.M. Meier, and D.C. H. Olson, Elsevier, pp. 10-15, which is hereby incorporated by reference.

Particularly preferred medium pore molecular sieves useful in the present method are described, for example, in US Pat. Nos. 5,135,638 and 5,282,958, the entire contents of which are hereby incorporated by reference. In US Pat. No. 5,282,958, such medium pore size molecular sieves have fine crystallite sizes of about 0.5 microns or less, and pores having a minimum diameter of at least about 4.8 mm and a maximum diameter of about 7.1 mm. The catalyst, when 0.5 gram of it is placed in a tube reactor, at 370 ° C., 1200 pounds per square inch gauge pressure, 160 ml / min hydrogen flow rate, and 1 ml / hour feed rate of hexadecane. Has sufficient acidity to convert at least 50%. This catalyst also exhibits an isomerization selectivity of 40 percent or more when used under conditions that result in 96% conversion of linear hexadecane (n-C ₁₆ ) to other species (isomerization selectivity is Determined as follows: 100 × (weight percent of branch C ₁₆ in product) / (weight percent of branch C ₁₆ in product + weight percent of C _{13− in} product)).

  Such particularly preferred molecular sieves are further characterized by pores or channels having a crystallographic free diameter in the range of about 4.0 to 7.1 inches, preferably in the range of 4.0 to 6.5 inches. The crystallographic free diameter of the channels of molecular sieves is described in “Atlas of Zeolite Framework Types”, 5th revised edition, 2001, Ch. Baerlocher, W.M. M.M. Meier, and D.C. H. Olson, Elsevier, pp. 10-15, which is hereby incorporated by reference.

  If the crystallographic free diameter of the molecular sieve channel is not known, the effective pore size of the molecular sieve can be measured using standard adsorption techniques and hydrocarbon compounds with known minimum motion diameters. . Breck, “Zeolite Molecular Sieves”, 1974 (especially Chapter 8); Anderson et al., J. Biol. See Catalysis 58, 114 (1979); and U.S. Pat. No. 4,440,871. These directly related parts are incorporated herein by reference. Standard techniques are used to perform adsorption measurements to determine pore size. If at least 95% of the equilibrium adsorption value on this molecular sieve is not reached in less than about 10 minutes, it is convenient to consider it as a specific molecule to be excluded (p / po = 0.5; 25 ° C.). Medium pore molecular sieves typically accept molecules having a kinematic diameter of 5.3 to 6.5 mm with little interference.

  The hydroisomerization catalyst useful in the present invention comprises a noble metal active as a catalyst. The presence of a catalytically active noble metal results in improved products, in particular viscosity index and stability. Typical catalytically active noble metals include platinum and palladium and mixtures thereof, with platinum being preferred. When platinum and / or palladium are used, the total amount of active noble metal is typically in the range of 0.1 to 5 weight percent of the total catalyst, usually 0.1 to 2 weight percent, and 10 weight percent. Never exceed.

  This refractory oxide support can be selected from the oxide supports conventionally used in catalysts, including silica, alumina, silica / alumina, magnesia, titania and combinations thereof.

  The hydroisomerization conditions are adjusted as described above to obtain a lubricating base oil having specific branching characteristics, and thus depend on the characteristics of the feedstock used. In general, the hydroisomerization conditions of the present invention maintain the conversion of wax to a material boiling between about 650 and 1400 ° F. between 40 and 95 weight percent in the production of lubricating base oils. It is such a moderate thing.

Mild hydroisomerization conditions are achieved by operating at lower temperatures, liquid hourly space velocity (LHSV), generally between about 390 and 650 ° F. and generally between about 0.5 and 20 hours ^−1. The This pressure is typically about 15 to 2500 pounds per square inch gauge, preferably about 50 to 2000 pounds per square inch gauge, more preferably about 100 to 1500 pounds per square inch gauge, and more preferably about 150 to 1000. A pound per square inch gauge, more preferably about 250 to 600 pounds per square inch gauge. Using sulfurized shape-selective medium pore noble metal-containing molecular sieve catalyst, enhanced isomerization selectivity is provided by low pressure, which results in improved isomerization and less decomposition of the feedstock Yield. Exemplary methods are described in US Pat. Nos. 5,135,638, 5,246,566, and 6,337,010, the entire contents of which are hereby incorporated by reference.

  Furthermore, using the sulfurized shape-selective medium pore noble metal-containing molecular sieve catalyst according to the present invention, this hydroisomerization process can be performed at higher pressures while maintaining acceptable yield and quality of the lubricating base oil product. Can also be implemented. Indeed, the present invention provides a hydroisomerization process that can be carried out at relatively higher pressures to achieve an acceptable yield of a high quality lubricating base oil product. By carrying out the hydroisomerization process using a sulfurized shape-selective medium pore noble metal-containing molecular sieve catalyst, an acceptable yield of high quality lubricating base oil is provided even at relatively high pressures. By sulfiding the catalyst, the yield of the lubricating base oil produced is improved when the hydroisomerization reaction is carried out at both a relatively high pressure and a relatively low pressure, but the hydroisomerization is carried out at a high pressure. If so, the effect on the yield of the lubricating base oil product produced is more pronounced. Since it may be difficult to operate this hydroisomerization process at relatively low pressures, the sulfurized catalyst according to the present invention surprisingly achieves an acceptable yield of high quality lubricating base oil. A process is provided in which hydroisomerization can be operated at relatively higher pressures. Thus, in one embodiment, it is preferred to carry out the hydroisomerization process at a relatively higher pressure (ie, between about 500 and 1000 pounds per square inch gauge).

  During the hydroisomerization process, typically at a hydrogen to feed ratio of about 0.5-30 MSCF / bbl (1000 standard cubic feet per barrel), preferably about 1-10 thousand standard cubic feet / barrel. , Hydrogen is present in the reaction zone. Hydrogen can be separated from the product and recycled to the reaction zone.

Solvent Dewaxing According to the present invention, at least a portion of the lubricating base oil produced by the hydroisomerization method can be solvent dewaxed. Solvent dewaxing techniques are known in the art. Solvent dewaxing involves residual waxy molecules by dissolving the waxy component in a solvent such as methyl ethyl ketone, methyl isobutyl ketone, or toluene; precipitating the waxy component and then removing the waxy component by filtration. Can also be used to remove. Solvent dewaxing is discussed in “Chemical Technology of Petroleum”, 3rd edition, by William Gruse and Donald Stevens (McGraw Hill, New York, 1960), pp. 566-570. See also U.S. Pat. Nos. 4,477,333, 3,773,650, and 3,775,288.

  In accordance with the present invention, solvent dewaxing is performed at least of the product from the hydroisomerization process to remove any remaining unconverted waxy components following the isomerization step (s). It is advantageous to use it for dewaxing a part. Wax extracted from the solvent dewaxing process (referred to as “crude wax”) may be recycled to the hydroisomerization process of the present invention to obtain higher yields of lubricating base oil.

Hydrotreating and hydrofinishing Hydrotreating and hydrofinishing are optional processing steps that can also be included in the method of the present invention. Hydrotreating can be performed on the waxy hydrocarbon feed prior to hydroisomerization. Hydrotreating means a catalytic process usually carried out in the presence of free hydrogen, whose main purpose is from the feedstock to various metal contaminants such as arsenic, heteroatoms such as sulfur and nitrogen, and It is to remove aromatic compounds. In general, in the hydrotreating step, it is desirable to minimize the amount that the hydrocarbon molecules break down (ie, larger molecules are broken into smaller ones). During hydrotreating, unsaturated hydrocarbons are fully or partially hydrogenated. The waxy hydrocarbon feed to the process of the present invention may be hydrotreated prior to hydroisomerization.

  Catalysts used to perform hydrotreating operations are well known in the art. For a general description of hydrotreating and typical catalysts used in this process, see, for example, US Pat. Nos. 4,347,121 and 4,810,357, the entire contents of which are hereby incorporated by reference. Please refer to the issue. Suitable catalysts include noble metals of Group VIIIA (in accordance with the International Union of Pure and Applied Chemistry 1975 rules) such as platinum or palladium supported on an alumina or silica matrix, and nickel supported on an alumina or silica matrix. -There are Groups VIII and VIB such as molybdenum or nickel-tin. U.S. Pat. No. 3,852,207 describes suitable noble metal catalysts and mild conditions for carrying out this reaction. Other suitable catalysts are described, for example, in US Pat. Nos. 4,157,294 and 3,904,513. Non-noble metal hydrides such as nickel-molybdenum are usually present as oxides in the final catalyst composition, but can also be used in their reduced or sulfided form.

  Preferred non-noble metal catalyst compositions are greater than about 5 weight percent, preferably about 5 to 40 weight percent molybdenum and / or tungsten, and at least about 0.5 weight percent, generally calculated as the corresponding oxide. About 1 to 15 weight percent nickel and / or cobalt. Catalysts containing noble metals such as platinum include greater than 0.01 percent metal; in some embodiments, between about 0.1 and 1.0 weight percent metal. Combinations of noble metals such as a mixture of platinum and palladium can also be used.

Typical hydrotreating conditions vary over a wide range. Generally, the overall LHSV is about 0.25 to 2.0 hours ⁻¹ , preferably about 0.5 to 1.0 hours ⁻¹ . The hydrotreating hydrogen partial pressure may exceed about 200 pounds per square inch absolute, and is preferably in the range of about 500 to 2000 pounds per square inch absolute. The hydrogen recycle rate is typically greater than about 50 standard cubic feet / barrel, preferably between 1000 and 5000 standard cubic feet / barrel. The temperature in the hydrotreating reactor may be in the range of about 300-750 ° F. (150-400 ° C.), preferably in the range of about 450-600 ° F. (230-315 ° C.).

  Hydrofinishing is a hydrotreating process that can be performed as a final step on a lubricating base oil product in a lubricating base oil production process. This final step is intended to improve the UV stability and appearance of the product by removing traces of aromatics, olefins, color bodies, and solvents. As used in this disclosure, the term UV stability refers to the stability of a lubricating base oil or finished lubricant when exposed to UV light and oxygen. Instability represents the dark color that occurs when it forms a discernable precipitate, usually seen as floc or cloudy, or when exposed to ultraviolet light and air. A general description of hydrofinishing can be found in US Pat. Nos. 3,852,207 and 4,673,487. Clay treatment to remove these impurities is an alternative final process step.

Oligomerization The waxy hydrocarbon feed used in the process of the present invention may comprise an oligomerized Fischer-Tropsch derived olefin. Depending on the conditions under which the Fischer-Tropsch synthesis is carried out, the Fischer-Tropsch condensate contains different amounts of olefins. In addition, most Fischer-Tropsch condensates contain some alcohol that can be readily converted to olefins by dehydration. As already mentioned, this condensate is also rich in olefins via a cracking operation, preferably by pyrolysis. In one embodiment of the invention, these olefins can be oligomerized to yield Fischer-Tropsch derived olefins. During oligomerization, not only is the lighter olefin converted to a heavier molecule, but the oligomer's carbon skeleton is branched where the molecule is added. The introduction of branching into the molecule reduces the pour point of the product.

  Olefin oligomerization has been reported in the literature and various commercial methods are available. See, for example, U.S. Pat. Nos. 4417088, 4434308, 4827064, 4827073, and 4990709. Although various types of reactor arrangements can be used, fixed catalyst bed reactors are commercially employed. Recently, methods have been proposed for performing oligomerization in ionic liquid media. Since the oligomerization catalyst is very active and the contact between the catalyst and the reactants is efficient, the separation of the catalyst from the oligomerization product is facilitated.

The oligomerization reaction takes place over a wide range of conditions. Typical temperatures for carrying out the reaction are in the range of about 32-800 ° F. (0-425 ° C.). Other conditions include a space velocity of 0.1-3 hours- ¹ and a pressure in the range of about 0-2000 pounds per square inch gauge. Examples of the oligomerization reaction catalyst include zeolite, clay, resin, BF ₃ complex, HF, H ₂ SO ₄ , AlCl ₃ , ionic liquid (preferably Bronsted acid or Lewis acid component, or Bronsted acid and Lewis An ionic liquid containing a combination of acid components), transition metal based catalysts (such as Cr / SiO ₂ ), superacids, etc., and can include virtually any acidic material. In addition, non-acidic oligomerization catalysts may be used, including certain organometallic or transition metal oligomerization catalysts such as zirconocene.

Lubricating base oil product and properties The lubricating base oil made by the method of the present invention is of high quality, characterized by the viscosity index and pour point of the lubricating base oil. That is, the lubricating base oil has a high viscosity, a low pour point, and an exceptionally high VI.

  A lubricating base oil having a high viscosity index is desirable. Viscosity index (VI) is an empirical unitless numerical value showing the effect of temperature change on the kinematic viscosity of oil. A liquid becomes low viscosity when heated and changes with temperature. The higher the VI of the oil, the lower the tendency of the viscosity to change with temperature. High VI lubricants are required when a relatively constant viscosity is required at any time over a wide range of temperature changes. For example, in an automobile, the engine oil must flow freely enough to allow cold start, but must be viscous enough to provide maximum lubrication after warm-up. VI is measured as described in ASTM D 2270-93. The lubricating base oil of the present invention has a high viscosity index in the range of about 140-190.

  The pour point is the temperature at which a sample of lubricating base oil begins to flow under carefully controlled conditions. As used herein, when pour points are indicated, unless otherwise indicated, this is determined by the standard analysis method ASTM D 5950-02. The lubricating base oil according to the present invention has an excellent pour point. The pour point of this lubricating base oil is between about -5 and -60 ° C. Preferably, the pour point of the lubricating base oil is less than −9 ° C., more preferably ≦ −15 ° C., and even more preferably less than −15 ° C.

  The cloud point is a complementary measurement of the pour point and is expressed as the temperature at which the lubricant base oil sample begins to develop haze under carefully defined conditions. The cloud point can be measured by, for example, ASTM D 5773-95. Lubricating base oils with branches optimized according to the present invention have cloud points below 0 ° C.

  Furthermore, the lubricating base oils of the present invention typically have high oxidative stability, high UV stability, low volatility and excellent low temperature properties. The lubricating base oil of the present invention has a kinematic viscosity at 100 ° C. of between about 2 and 40 centistokes. Preferably, the lubricating base oil of the present invention has a kinematic viscosity greater than 2.6 centistokes at 100 ° C., more preferably greater than 3 centistokes at 100 ° C.

  The American Petroleum Institute (API) classifies base oils according to their chemical composition. As defined by the API, Group III oils are very high viscosity index oils (> 120) with a total sulfur content of less than 300 ppm and a saturate content of 90% or more. API Group III oils have also been traditionally produced by vigorous hydrocracking and / or wax isomerization. The lubricating base oils of the present invention are generally classified as API Group III base oils. If they are produced from a low total sulfur content waxy feed, such as a Fischer-Tropsch feed, this lubricating base oil will also have a total sulfur content of less than 300 ppm.

  Lubricating base oils according to the present invention made from a Fischer-Tropsch waxy feedstock generally have a total sulfur content of less than about 5 ppm. Total sulfur is measured using ultraviolet fluorescence according to ASTM D 5453-00.

Blends The lubricating base oils of the present invention may be used alone or as a conventional Group I base oil, conventional Group II base oil, conventional Group III base oil, isomerized petroleum wax, poly alpha olefin (PAO). ), Poly internal olefins (PIO), diesters, polyol esters, phosphate esters, alkylated aromatic compounds, and mixtures thereof may be blended with an additional base oil.

  Because the lubricating base oils of the present invention have excellent low temperature fluidity, high VI, and high oxidative stability, they are ideal blending raw materials for improving conventional lubricating base oils.

  When the lubricating base oil of the present invention is blended with one or more additional lubricating base oils, the additional base oil may be present in an amount less than 95% by weight of the resulting base oil total composition. preferable.

Finished lubricants Lubricating base oils are the most important components of finished lubricants and generally constitute more than 70% of the finished lubricant. The finished lubricant contains a lubricating base oil and at least one additive. Finished lubricants can be used in automobiles, diesel engines, axles, transmissions, and industrial applications. The finished lubricant must meet the specifications specified by the relevant management organization for its intended use.

  The lubricating base oils of the present invention are useful in commercial finished lubricants. As a result of its excellent VI and low temperature properties, the lubricating base oil of the present invention is suitable for formulating finished lubricants intended for many of its applications. Furthermore, the excellent oxidative stability of the lubricating base oils of the present invention makes them useful in finished lubricants for many high temperature applications.

  The lubricating base oil of the present invention includes automobile engine oil, natural gas engine oil, automatic transmission oil, industrial gear oil, turbine oil, fabric oil, heat transfer oil, hydraulic fluid, paper machine oil, spindle oil, rock drill oil, Suitable for blending into various finished lubricants, including but not limited to pump oils, compressor oils, way oils, and metalworking oils. The lubricating base oils of the present invention may also be used as workover fluids, packer fluids, coring fluids, finishing fluids, and other oil field and well maintenance applications.

  Additives that can be blended with the lubricating base oil of the present invention to provide a finished lubricant composition include those intended to improve the selected properties of the finished lubricant. Typical additives include, for example, antiwear additives, EP agents, detergents, dispersants, antioxidants, pour point depressants, VI improvers, viscosity modifiers, friction modifiers, demulsifiers, antifoaming agents. , Corrosion inhibitors, rust inhibitors, seal swelling agents, emulsifiers, wetting agents, lubricity improvers, metal deactivators, gelling agents, adhesives, bactericides, fluid loss prevention additives, colorants, etc. is there.

Assuming the finished lubricant has the necessary pour point, kinematic viscosity, flash point, and toxicity, blend other hydrocarbons with the lubricating base oil, such as those described in US Pat. Nos. 5,096,883 and 5,189,0102. can do. These other hydrocarbons include base oils that are particularly useful in drilling fluids. As an example, U.S. Pat. No. 5,096,883 is a substantially non-toxic base oil consisting essentially of branched paraffins or branched chain paraffins substituted with ester functional groups, or mixtures thereof. The oil preferably relates to a base oil having between about 18 and about 40 carbon atoms per molecule, more preferably between about 18 and about 32 carbon atoms per molecule. US Pat. No. 5,189,012 is a branched-chain oligomer synthesized from one or more olefins containing a C _{2 to} C ₁₄ chain length, the oligomer consisting of oligomers having an average molecular weight of 120 to 1000 It relates to a synthetic hydrocarbon selected from

  Typically, the total amount of additives in the finished lubricant is approximately 1 to about 30 weight percent of the finished lubricant. However, since the lubricating base oil of the present invention has excellent properties including low pour point, high VI, and excellent oxidation stability, it can be made by other methods to meet the specifications for the finished lubricating oil. Smaller amounts of additives may be needed than is typically required for a base oil. The use of additives in finished lubricant formulations is documented in the literature and well known to those skilled in the art.

  The present invention is further illustrated by the following illustrative examples, but is not limited thereto.

Each of these examples was conducted in a continuous flow, high pressure pilot plant designed to hydrotreat a waxy hydrocarbon feedstock. The isomerization catalyst was SAPO-11 supported platinum prepared in the laboratory and contained 15 weight percent Catapal alumina binder. This catalyst was ground to 24-42 mesh before being charged into the reactor. The process conditions, it was possible to include LHSV of 1.0 h ^-1 on the isomerization catalyst, and 5300 a throughflow _{H 2} rate of standard cubic feet / barrel. A second reactor containing the pulverized Pt—Pd / SiO ₂ —Al ₂ O ₃ hydrofinishing catalyst and operating at 450 ° F. and 2 hours ⁻¹ LHSV with the entire effluent from the isomerization reactor Sent directly to. The feedstock used in these examples is hydrotreated Fischer-Tropsch derived wax, and the properties of this feedstock (hydrotreated Fischer-Tropsch wax) are as follows.

  In the following examples, the effectiveness of sulfiding hydroisomerization catalysts was evaluated by measuring 650 ° F. + yield (weight percent) and viscosity index of isomerized Fischer-Tropsch wax. 650 ° F. + yield (weight percent) is the weight percent of the total product boiling above 650 ° F. and is known in the art to be defined or calculated at a specific pour point.

(Example 1)
Hydroisomerization at 1000 pounds per square inch gauge using a sulfided SAPO catalyst This example illustrates the effect of sulfiding a SAPO-11 catalyst. In FIG. 1, the 650 ° F. + yield (weight percent) obtained when the Fischer-Tropsch derived wax is hydroisomerized is shown in three situations: 1) the SAPO11 catalyst prior to the hydroisomerization reaction. Plotted as a function of pour point (° C.) for the case when not sulfidized, 2) when the catalyst was presulfided, and 3) when the catalyst was resulfurized after 2040 hours of operation. Each of the three experiments was performed at a hydrogen partial pressure of 1000 pounds per square inch gauge.

  For comparison purposes, consider a data point at a pour point of about -15 ° C. The 650 ° F. + yield of the non-sulfurized catalyst was about 32 weight percent, indicating an increase of about 18 weight percent when the catalyst was presulfided, increasing to a yield of about 50 weight percent. After resulfiding the catalyst, the yield increased to about 65 weight percent with an additional 15 weight percent added.

  This viscosity index increased similarly by sulfiding as shown in FIG. At the pour point of −15 ° C., the viscosity index of the hydroisomerized wax is increased from about 155 to 162 by presulfiding the catalyst, and this viscosity index is further reduced by resulfiding after 2040 hours of operation. Increased to 172. This means an absolute increase of about 7 by presulfiding and about 10 by resulfiding.

(Example 2)
Hydroisomerization at various pressures using a sulfided SAPO catalyst The effect of sulfiding at two different pressures (and the effect of pressure without sulfiding) is shown in FIGS. The 1000 pound / square inch gauge curves of FIGS. 3 and 4 are the same as those of FIGS. 1 and 2, in other words, simply a replot of the 1000 pound / square inch gauge data. Reducing the hydrogen partial pressure during hydroisomerization from 1000 to 300 pounds per square inch gauge increases the 650 ° F. + yield from about 35 to 68 weight percent and increases the viscosity index of about 155 to 168. The result was. Thus, this example shows that reducing the hydroisomerization pressure improves both the hydroisomerization yield and the viscosity index.

  Further, comparing FIGS. 1 and 2 with FIGS. 3 and 4, the sulfidation of SAPO-11 is at a higher pressure (eg, 1000 lb / in 2 gauge) than at a lower pressure (eg, 300 lb / in 2 gauge). An example of having an advantageous effect is shown. At 300 pounds per square inch gauge, the sulfidation of the SAPO-11 catalyst has a slight effect on the 650 ° F. + yield and a slight effect on the viscosity index (an increase of about 5) within the range where the pour point is plotted. Gave. Again, the associated pressure refers to the hydrogen partial pressure in the hydroisomerization reactor, which is substantially the same (or nearly the same) as the total pressure.

(Example 3)
Hydroisomerization using a sulfurized zeolite catalyst This example was performed as described in Example 1, except that SSZ-32 was used as the catalyst. FIG. 5 shows the 650 ° F. + yield (weight percent) from Fischer-Tropsch wax hydroisomerized at 1000 pounds per square inch gauge for both sulfurized and non-sulfurized SSZ-32 catalysts. The yield was about 55 (at a pour point of -15 ° C). Similarly, this viscosity index was about 175.

Example 4
The influence of the iso-to-linear ratio of C ₄ sulfide hydroisomerization in operation using a SAPO catalyst sulfided during operation shown in FIG. In this embodiment, the SAPO-11 catalyst, sulfided during operation to 150 hours after the hydroisomerisation step was plotted the ratio of iso-to-linear C ₄ as a function of time. FIG. 7 illustrates that sulfiding during the operation of the catalyst resulted in an increase of about 0.2 to 0.8, with the ratio of iso to linear C ₄ increasing more than 4 times. . When the ratio of the iso-to-linear C ₄ is higher, showing catalytic, more improved selectivity of isomerization reactions than the decomposition reaction.

(Example 5)
Hydroisomerization Using Pre-Sulphided SAPO Catalyst FIG. 8 shows the effect of pre-sulfidation of SAPO-11 catalyst on the amount of light hydrocarbons produced by hydroisomerization. The total pressure in the reactor was 1000 pounds per square inch gauge and the temperature was 650 ° F. The amount of linear C ₄ and linear C ₅ is considerably reduced, reduction in the amount of iso C ₄ and iso C ₅ is much less than that.

(Example 6)
Various Temperature Hydroisomerization Using Pre-Sulphided SAPO Catalyst FIGS. 9A-C illustrate the relationship between several observed hydroisomerization temperatures and pressures. The graph in FIG. 9C shows hydroisomerism as a function of pour point for each of the four runs shown in FIGS. 9A and 9B (at 150, 300, 500, and 1000 pounds per square inch gauge total pressure). The former graph reports the result of 650 ° F. + yield (weight percent), and the latter graph reports the viscosity index result. In addition to the improved production yield and viscosity index with the sulfided SAPO catalyst according to the embodiments, the advantage of producing a lubricating base oil at low pressure was that the hydroisomerization process was otherwise. It can be carried out at operating temperatures that are significantly lower than those that would be.

  Lowering the hydroisomerization reaction temperature provides a wider temperature range for operating this reaction. Referring to FIG. 9C, for example, at a pour point of −15 ° C., if the operating pressure is reduced from 1000 to 500 pounds per square inch gauge, the temperature required for proper hydroisomerization with the catalyst is about Decrease by 22 ° C. If the operating pressure is reduced from 1000 to 300 pounds per square inch gauge under similar conditions, the required temperature is reduced by about 37 ° C. Finally, if the operating pressure is reduced from 1000 to 150 pounds per square inch gauge, the required temperature is reduced by about 47 ° C.

  All references, patents and patent applications cited in this application are as if each individual document, patent application or patent disclosure was specifically and individually indicated to be incorporated by reference in its entirety. The entirety of which is hereby incorporated by reference.

  Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. Other objects and advantages will become apparent to those skilled in the art upon review of the above description. Accordingly, the invention is to be construed as including all structure and methods that fall within the scope of the appended claims.

2 is a graph showing the impact on yield of using a sulfided SAPO-11 catalyst to hydroisomerize a Fischer-Tropsch waxy feedstock at 1000 pounds per square inch gauge. 2 is a graph showing the effect on viscosity index of using a sulfided SAPO-11 catalyst to hydroisomerize a Fischer-Tropsch waxy feed at 1000 pounds per square inch gauge. 2 is a graph showing the yield impact of using a sulfided SAPO-11 catalyst to hydroisomerize a Fischer-Tropsch waxy feed at different pressures. 2 is a graph showing the effect on viscosity index of using a sulfided SAPO-11 catalyst to hydroisomerize a Fischer-Tropsch waxy feed at different pressures. 2 is a graph showing the impact on yield of using a sulfurized zeolite catalyst to hydroisomerize a Fischer-Tropsch waxy feed at 1000 pounds per square inch gauge. 2 is a graph showing the effect on viscosity index of using a sulfurized zeolite catalyst to hydroisomerize a Fischer-Tropsch waxy feed at 1000 pounds per square inch gauge. Of using SAPO catalyst sulfided during operation, it is a graph showing the effect of the iso-to-linear C ₄ ratio. 2 is a graph showing the effect on the amount of light hydrocarbons produced using a presulfided SAPO catalyst. 2 is a graph showing the impact on yield of using a presulfided SAPO catalyst to hydroisomerize a Fischer-Tropsch waxy feed at various pressures. 2 is a graph showing the effect on viscosity index of using a presulfided SAPO catalyst to hydroisomerize a Fischer-Tropsch waxy feed at various pressures. 2 is a graph showing the temperature effect of using a presulfided SAPO catalyst to hydroisomerize a Fischer-Tropsch waxy feed at various pressures.

Claims (18)

A method for producing a lubricating base oil from a waxy hydrocarbon feedstock comprising:
a) sulfiding a shape selective, medium pore size, noble metal-containing molecular sieve catalyst to provide a sulfided catalyst, wherein the molar ratio of sulfur to noble metal in the sulfided catalyst is greater than 1;
b) hydrolytically isolating the waxy hydrocarbon feedstock by contacting the waxy hydrocarbon feedstock with a catalyst sulfided under hydroisomerization conditions to produce a lubricating base oil;
And the sulfidation step is an in-operation sulfidation step . The waxy hydrocarbon feedstock is gas oil, lubricating oil feedstock, synthetic oil, Fischer-Tropsch derived wax, oligomerized Fischer-Tropsch derived olefin, wax lower oil, crude wax, deoiled wax, linear α-olefin The method of claim 1, wherein the method is selected from the group consisting of waxes, microcrystalline waxes, and mixtures thereof. The process of claim 2 wherein the waxy hydrocarbon feedstock is a Fischer-Tropsch derived wax. The method according to any one of claims 1 to 3, wherein the molecular sieve has a channel diameter in the range of 4.0 to 7.1 mm. The method of claim 4, wherein the molecular sieve is non-zeolitic. 6. The method of claim 5, wherein the catalyst is a SAPO catalyst. 7. The method of claim 6, wherein the SAPO catalyst is selected from the group consisting of SAPO-11, SAPO-31, and SAPO-41. The method according to any one of the preceding claims, wherein the noble metal is selected from the group consisting of platinum, palladium, and mixtures thereof. 9. The method of any one of claims 1 to 8, wherein the hydroisomerization conditions comprise a total pressure between 150 and 1000 pounds per square inch gauge. The method of claim 9, wherein the hydroisomerization conditions comprise a total pressure between 150 and 500 pounds per square inch gauge. The method of claim 10, wherein the hydroisomerization conditions comprise a total pressure between 150 and 300 pounds per square inch gauge. The method of claim 9, wherein the hydroisomerization conditions comprise a total pressure between 500 and 1000 pounds per square inch gauge. 13. A method according to any one of the preceding claims, wherein between 40 and 95 weight percent of the lubricating base oil has a boiling point between 650 and 1400 ° F. 14. A method according to any one of the preceding claims, wherein the lubricating base oil has a viscosity index between 140 and 190. 15. A process according to any one of the preceding claims, wherein the lubricating base oil has a pour point between -5 and -60 ° C. 16. A method according to any one of the preceding claims, wherein the lubricating base oil has a viscosity at 100 ° C of greater than 3 centistokes. 17. A method according to any one of the preceding claims, further comprising the step of solvent dewaxing at least a portion of the lubricating base oil, thereby removing the crude wax. The method of claim 17, further comprising hydroisomerizing the crude wax with a waxy hydrocarbon feedstock.

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