KR20050070045A - Heavy hydrocarbon composition with utility as a heavy lubricant base stock - Google Patents

Abstract

A heavy hydrocarbon composition with utility as a heavy hydrocarbon base stock comprising at least 95 wt.% paraffin molecules, of which at least 90 wt.% are isoparaffin, containing hydrocarbon molecules having consecutive numbers of carbon atoms, is a liquid at 100 °C, at which temperature its kinematic viscosity, as measured by ASTM D-445, is above 8 cSt, has an initial boiling point of least 850 °F (454 °C) and an end boiling point of at least 1000 °F (538 °C), wherein the branching index (BI), as measured by the percentage of methyl hydrogens, and the branching proximity (CH2>4), as measured by the percentage of recurring methylene carbons which are four or more carbon atoms removed from an end group or branch, of said isoparaffinic hydrocarbon molecules, are such that: (a) BI-0.5(CH 2>4)4)<45; as measured over the heavy hydrocarbon composition as a whole.

Description

HEAVY HYDROCARBON COMPOSITION WITH UTILITY AS A HEAVY LUBRICANT BASE STOCK}

The present invention relates to heavy hydrocarbon compositions useful as heavy lubrication base stocks, heavy lubrication base stocks and heavy lubricants formed from the base stocks produced by isomerizing Fischer-Tropsch waxes.

Heavy lubricants have been used for high viscosity applications where light oil based lubricants do not provide sufficient lubricity between moving parts such as heavy machine oils, gear boxes, deep drawing oils and manual transmissions. Heavy lubricants are prepared by mixing a heavy lubricating base material, which is heavy oil with lubricating oil properties, with at least one lubricating additive. Most heavy lubricating base stocks are derived from natural petroleum and contain aromatic unsaturateds, including polynuclear aromatic compounds, along with sulfur and nitrogen containing compounds. These compounds tend to reduce the viscosity and stability of oils and heavy lubricants. Purifying the oil to remove these components results in a lower yield of the product oil. Heavy paraffins can be purified to low levels of unsaturated and heteroatomic compounds, but have unacceptably high pour and cloud points.

There is a need for a relatively pure or higher quality heavy hydrocarbon composition that is liquid at least at the temperature of use and has utility in or as a heavy lubricating base stock.

U.S. Pat.No. 6,090,989 (Trewella et al.) Has a branching degree (BI), which is measured by percent of methyl hydrogen, and a percentage of repeating methylene carbon, which is at least 4 carbons removed from end groups or branches. The branching proximity (CH ₂ > 4) is (a) BI-0.5 (CH ₂ >4)> 15 when measured on the liquid hydrocarbon composition as a whole and (b) BI + 0.85 (CH ₂ > 4) < A liquid hydrocarbon composition of a paraffinic hydrocarbon component of 45 is disclosed. The base stock of US Pat. No. 6,090,989 is characterized by a very low pour point (PP) of -18 ° C or below and a dynamic viscosity range of preferably about 4 to about 8 cSt at 100 ° C. Although the compositions according to US Pat. No. 6,090,989 have excellent utility as lubricating base stocks, certain applications call for the use of heavy lubricants having a kinematic viscosity higher than 8 cSt, especially at 100 ° C. This will generally require the presence of relatively long chain hydrocarbon molecules in the base stock. However, increasing the chain length of hydrocarbon molecules in the hydrocarbon mixture will generally result in an undesirable increase in pour point and cloud point. Alternatively, additives such as viscosity index improvers and pour point and cloud point depressants could be used to impart the desired properties to the lubricant. In addition to the high cost of the use of additives, the additives tend to be lowered in use. Accordingly, it is an object of the present invention to provide a composition having a relatively high viscosity, good lubricity and oxidative stability but low pour point and cloud point.

In addition, there is always a need for hydrocarbon compositions useful for pharmaceutical formulations, such as in chemical and pharmaceutical preparations, for example as heavy white oils, pharmaceutical oils, carriers or substrates. Such uses generally require pure and chemically inert substances that will not cause allergies, for example in medical applications. On the other hand, there is a need for hydrocarbon compositions with very low aromatic and heteroatom containing components.

The present invention provides a heavy hydrocarbon composition having both high viscosity and low pour point and cloud point.

Summary of the Invention

The present invention relates to a relatively pure high quality heavy hydrocarbon composition, a heavy lubricating base material, and a heavy lubricating agent prepared from a heavy lubricating base material and useful as a heavy lubricating base material.

Heavy hydrocarbon compositions are oily liquids consisting mostly of saturated paraffinic hydrocarbon molecules (e.g., at least 98% by weight) and having a kinematic viscosity higher than 8 cSt (centistoke) at 100 ° C. 5%) boiling point and terminal (95%) boiling point of at least 1000 ° F. (538 ° C.). The heavy hydrocarbon composition consists of at least 95% by weight of paraffin molecules, of which at least 90% by weight are isoparaffins. Isoparaffins constitute at least 90% by weight of the paraffinic molecules of the heavy hydrocarbon composition according to the invention. Heavy hydrocarbon compositions contain hydrocarbon molecules with consecutive carbon atoms. The degree of branching (BI) of the isoparaffinic hydrocarbon molecule (hereinafter referred to as the branching index (BI)), measured by the percentage of methyl hydrogen, and the percentage of repeating methylene carbon, which is at least 4 carbon atoms removed from the end group or branch. The branching proximity (or branching proximity) (CH ₂ > 4) as measured by (a) BI-0.5 (CH ₂ > 4) <15 when measured for the heavy hydrocarbon composition as a whole, (b) BI +0.85 (CH ₂ > 4) <45. Heavy hydrocarbon compositions have utility in heavy lubrication base stocks or as heavy lubrication base stocks.

Branching proximity (CH ₂ > 4) accounts for the n-paraffinic properties of paraffinic molecules in hydrocarbons. In general, in order to obtain good lubricity, the composition requires containing paraffin molecules with relatively high n-paraffinic properties, i.e. a small number of branches and / or short branches. However, paraffins with relatively high n-paraffinic properties are expected to exhibit undesired pour and clouding points, since n-paraffins tend to crystallize from the paraffin mixture at rather high temperatures.

The branching index, measured by percent of methyl hydrogen, is a measure of the number of branches attached to the backbone. If there are many branches and the branches are predominantly methyl groups, the branching index will be large.

For example, given a certain total number of carbon atoms, paraffin molecules with long branches and a large number of branches on a relatively short backbone, i.e., with somewhat less n-paraffinic properties, have relatively less branching proximity (CH ₂ > 4). Will have Paraffin molecules with the same total number of carbon atoms but with fewer branches and / or branches with greater distances to each other or to end groups and with relatively long backbones, ie paraffin molecules with more n-paraffinic properties, are relatively large branches It will have chemical proximity (CH ₂ > 4).

US Pat. No. 6,090,989 relates to liquid hydrocarbon compositions with BI-0.5 (CH ₂ >4)> 15. It has now been found that heavy hydrocarbon compositions with surprisingly high viscosity but low pour point and cloud point can be obtained if (a) BI-0.5 (CH ₂ > 4) <15. On the other hand, according to the present invention, the branching proximity (CH ₂ > 4) is rather large compared to the compositions exemplified in US Pat. No. 6,090,989. This finding was unexpected because the heavy hydrocarbon composition according to the invention contains paraffin molecules with more n-paraffinic properties exhibited by relatively large branching proximity and still has very low pour and cloud points. As a result, the findings contradict the conventional idea that low pour point and cloud point require less n-paraffins and relatively large isoparaffin properties.

BI is preferably less than 24 and branching proximity (CH ₂ > 4) is preferably greater than 17.

In another embodiment, the present invention relates to a heavy lubricant prepared by mixing the heavy lubricating substrate raw material of the present invention with at least one lubricating additive. The heavy hydrocarbon composition of the present invention is useful as a heavy lubricating base material, but will have other uses, such as, for example, heavy white oils, pharmaceutical oils, carriers or substrates, for pharmaceutical formulations in chemical and pharmaceutical preparations, and the like. As such, in another embodiment, the present invention provides a pharmaceutical formulation for use in or in the manufacture of heavy white oils, pharmaceutical oils, carriers or substrates, at least in part for use in or based on the heavy hydrocarbon composition of the present invention. It includes one or more.

In another embodiment, the present invention relates to a base stock comprising the heavy hydrocarbon composition according to the present invention. On the other hand, this embodiment relates to the use of a heavy hydrocarbon composition in or as a base material. Preferably, the base material according to the invention consists of a heavy hydrocarbon composition.

The figure is a graph depicting BI and% CH ₂ > 4 derived from NMR spectra of data of US Pat. No. 6,090,989 comprising the heavy hydrocarbon composition of the present invention, a comparative example herein, and other hydrocarbon compositions as described above. The disclosure of US Pat. No. 6,090,989 is incorporated herein by reference in its entirety. The dark areas on the drawing define the NMR parameter zones of the heavy hydrocarbon composition of the present invention. Only heavy hydrocarbon compositions and PAO based raw materials of the present invention, preferably derived from Fischer-Tropsch synthesized waxy hydrocarbons, fall into this region of the parameter zone. The molecular compositions of PAO raw materials are (i) they do not contain hydrocarbon molecules with consecutive carbon atoms, and (ii) the percentage of hydrogen atoms from CH ₃ groups on the molecule is less than 15, while in the case of the heavy hydrocarbon compositions of the present invention It is preferably greater than 20 and (iii) for the PAO feedstock the percentage of hydrogen atoms from the CH group is preferably greater than 3, while for the heavy hydrocarbon composition of the invention it is preferably less than 2 in that Different from the hydrocarbon composition.

The present invention comprises at least 90% by weight of paraffin molecules, wherein at least 90% by weight isoparaffin, contains hydrocarbon molecules having consecutive carbon atoms, is liquid at 100 ° C, and has a kinematic viscosity of 8 cSt (ASTM). D-445) and having an initial and terminal boiling point of at least 850 ° F. and 1000 ° F. (454 ° C. and 538 ° C.), respectively, and the branching index (BI) measured by the percent of methyl hydrogen of the isoparaffinic hydrocarbon molecule. And branching proximity (CH ₂ > 4), measured by percent of repeating methylene carbon, which is at least 4 carbons removed from terminal groups or branches, is determined for the heavy hydrocarbon composition as a whole (a) BI-0.5 ( CH ₂ > 4) <15 and (b) BI + 0.85 (CH ₂ > 4) <45.

Preferably, the heavy hydrocarbon composition of the present invention is produced from Fischer-Tropsch wax and is mostly (at least 98% by weight) saturated paraffinic hydrocarbons, of which at least 90% by weight is acyclic hydrocarbon and at most 10% by weight is cyclic hydrocarbon. It is composed of At least 90% by weight, preferably at least 95% by weight, more preferably at least 98% by weight and most preferably at least 99% by weight of the paraffinic hydrocarbon molecules are isoparaffins. Paraffinic cyclic hydrocarbons may be present in amounts up to 5% by weight, but more typically will not exceed 1% by weight if present.

The kinematic viscosity of the heavy hydrocarbon composition of the present invention at 100 ° C., measured according to ASTM D-445, is greater than 8 cSt. The heavy hydrocarbon composition of the present invention contains molecules having consecutive carbon atoms and preferably at least 95% by weight of C ₃₀₊ hydrocarbon molecules. The initial boiling point is at least 850 ° F. (454 ° C.), preferably at least 900 ° F. (482 ° C.), and the end boiling point is at least 1000 ° F. (538 ° C.). Heavy hydrocarbon compositions are typically liquid at service temperature and pressure conditions, typically, but not always, ambient conditions of 75 ° F. (24 ° C.) and 1 atmosphere (101 kPa) pressure. The initial and terminal boiling point values referred to herein are nominal and refer to the T5 and T95 interception points (boiling temperatures) obtained by gas chromatography simulated distillation (GCD) using the method described below.

Branching measured by the degree of branching or branching index (BI) of the isoparaffinic hydrocarbon component measured by percent of methyl (CH ₃ ) hydrogen and the percentage of repeating methylene carbon which is at least 4 carbons removed from the end groups or branches. Proximity (or branching proximity) (CH ₂ > 4) is (a) BI-0.5 (CH ₂ > 4) <15 as measured as a heavy hydrocarbon composition as a whole, and (b) BI + 0.85 (CH _2). > 4) <45. BI is preferably less than 24 (BI <24) and branching proximity is preferably greater than 17 ((CH ₂ >4)> 17). In addition, the heavy hydrocarbon composition preferably contains at least 75% by weight of C ₃₅₊ hydrocarbon molecules.

The heavy hydrocarbon compositions of the present invention obtained by isomerizing Fischer-Tropsch wax are different from those derived from petroleum, slack wax, PAO oil, and lubricating base stocks disclosed in US Pat. No. 6,090,989.

Sulfur, nitrogen, and metals in the form of hydrocarbon compounds containing them are present in amounts less than 50 wppm. Heavy hydrocarbon compositions of the present invention made from Fischer-Tropsch wax generally contain less than 1 wppm of sulfur, nitrogen and metals. They were not detected by X-ray or Antek nitrogen test.

The heavy hydrocarbon composition of the present invention is a mixture of paraffinic hydrocarbons of various molecular weights, but the residual n-paraffin content remaining after hydrodewaxing is less than 5% by weight, more typically less than 1% by weight, more than half 95% or more by weight of oil molecules containing at least one branch which is this methyl branch. At least half, more preferably at least 75%, of the remaining branches are ethyl and comprise 25%, preferably less than 15%, of the total number of branches having at least 3 carbon atoms. The total number of branched carbon atoms is less than 25%, preferably less than 20%, more preferably less than 15% of the total number of carbon atoms comprising hydrocarbon molecules.

PAO oil is an oligomerization product of linear alpha-olefins, typically 1-decene, numbered with even numbers. As a result, the PAO oil molecule consists of a mixture of even-numbered carbon numbered hydrocarbon molecules that differ in number of carbon atoms by a multiple of the number of carbon atoms in the linear alpha olefin starting monomer. Even if a mixture of linear alpha olefin monomers having an even number of carbon atoms (eg decene and dodecene) is oligomerized to form a heavy lubricating base stock oil, the number of carbon atoms in the resulting hydrocarbon molecules will still have an even number of carbon atoms. It is a heavy hydrocarbon of the present invention that constitutes a hydrocarbon molecule having both even and odd carbon atoms and differs from each other by successive carbon atoms (e.g., 1, 2, 3, 4, 5, 6, 7 and more carbon atoms). It is different from the mixture of serially numbered hydrocarbon molecules that make up the composition.

Hydrocarbon molecules of the heavy hydrocarbon composition of the present invention that differ from each other by successive carbon atoms are the result of a Fischer-Tropsch hydrocarbon synthesis reaction in which an isomerized wax feed can be produced to form the heavy hydrocarbon composition of the present invention. Preferred heavy hydrocarbon compositions are prepared from synthetic sources rather than mineral oil based sources, and may be referred to as synthetic heavy hydrocarbon compositions, but the heavy hydrocarbon compositions of the present invention are not limited to those based on synthetic sources. In a preferred embodiment, however, the heavy hydrocarbon composition is based on synthetic sources, more preferably based on Fischer-Tropsch products.

In the Fischer-Tropsch hydrocarbon synthesis reaction, the source of carbon atoms is CO, and the hydrocarbon molecules consist of one carbon atom at a time. In contrast to oils based on PAO, the hydrocarbon molecules of the heavy hydrocarbon composition of the present invention have a more linear structure comprising a relatively long backbone with short branches and few branches. The orthodox textbook on PAO is a star molecule, specifically tridecane, which is described as three decane molecules attached to a central point. Although ideal star molecules exist in theory, nevertheless, PAO molecules have fewer and longer branches than the hydrocarbon molecules that make up the base material of the present invention.

Thus, the molecules constituting the heavy hydrocarbon composition of the present invention are preferably composed of at least 95% by weight of isoparaffin (having less than 5% by weight of saturated cyclic) having a relatively linear molecular structure, with less than half of the branches being 2 With more than one carbon atom, less than 25% of the total number of carbon atoms are present in the branch. In contrast to the present invention, in the molecules constituting the PAO oil, at least half of the branches contain at least two carbon atoms and at least 25% of the total number of carbon atoms is present in the branch.

As will be appreciated by those skilled in the art, lubricating base stocks are often referred to as lubricating or lubricating oil based stocks, including heavy lubricating base stocks, and are oils that boil in the lubricating oil range with lubricating quality, and various lubricants such as lubricants and greases. Useful for preparing The heavy hydrocarbon composition in the present invention boils in the heavy lubricating oil range. Fully formulated heavy lubricants or heavy lubricating oils are prepared by adding an additive package containing an effective amount of at least one additive, or more preferably more than one additive, to the heavy lubricating substrate raw material. Non-limiting examples of such additives include one or more of detergents, dispersants, antioxidants, antiwear additives, extreme pressure additives, pour point lowering agents, VI improvers, friction modifiers, demulsifiers, antioxidants, antifoams, corrosion inhibitors and seal swelling control additives. Can be mentioned.

The heavy hydrocarbon composition of the present invention preferably comprises a dewaxed oil, has a low temperature characteristic that can satisfy the desired specifications and requirements, and will be a clear and clear oily liquid under the temperature and pressure conditions used. Typically, but not always, will be an oily liquid at room temperature and pressure conditions of 75 ° F. (24 ° C.) and 1 atmosphere (101 kPa), and an oily liquid at a temperature of 100 ° C. and above pressure. In some cases, the cloud point may be higher than 75 ° F. (24 ° C.). Heavy hydrocarbon compositions of the present invention having a cloud point and pour point of 1 ° C. and −31 ° C., respectively, and a terminal boiling point above 1250 ° F. (677 ° C.) were prepared according to the present invention. The low temperature property requirements for both heavy lubrication base stock and finished heavy lubricant will vary and may depend on both the geographic location to be used and the intended use. The heavy lubricating composition is prepared by forming a mixture of the heavy lubricating substrate raw material of the present invention and an additive package containing an effective amount of at least one additive or more typically at least one additive as described above. The heavy lubricating base stock of the present invention used to form the mixture will typically be moderately hydrofinish and / or defoamed after hydrodewaxing to improve color, appearance and stability.

As is known, haze means cloudy or lack of transparency and becomes an appearance factor. Defoaming is typically accomplished by a catalytic or absorbent process that removes clouding components. Hydrocarbon finishing to improve oxidation stability and color is a very moderate relatively low temperature hydrogenation process that utilizes catalyst, hydrogen and mild reaction conditions to remove traces of heteroatomic compounds, aromatics and olefins. The hydrofinishing reaction conditions include a temperature of 302 to 662 ° F. (150 to 350 ° C.), preferably a temperature of 302 to 482 ° F. (150 to 250 ° C.), a total pressure of 400 to 3000 psig (2859 to 20786 kPa), 0.1 to 5 LHSV. (hr ^-1), preferably it comprises a liquid hourly space velocity range of from 0.5 to 3hr ^-1. The hydrotreating gas velocity will range from 2550 to 10000 scf / B (44.5 to 1780 m ³ / m ³ ). The catalyst will comprise a support component and one or more catalytic metal components of metals (Mo, W, Cr) from the group VIB and / or iron groups (Ni, Co) and precious metals (Pt, Pd) of group VIII. Groups VIB and VIII referred to herein refer to Groups VIB and VIII found in the Sargent-Weltz Periodic Table, copyrighted in 1968 by Sargent-Welch Scientific Company. . The metal or metals may be present as low as 0.1 wt% for precious metals and as high as 30 wt% of catalyst composition for non-noble metals. Preferred support materials are weak in acid and amorphous, such as, for example, alumina, silica, silica alumina, and super macroporous crystalline materials known as mesoporous crystalline materials, of which MCM-41 is the preferred support component. Crystalline metal oxides. The preparation and use of MCM-41 is disclosed, for example, in US Pat. Nos. 5,098,684, 5,227,353 and 5,573,657.

Waxy feeds or Fischer-Tropsch waxes comprise waxy hydrocarbon fractions produced in the Fischer-Tropsch hydrocarbon synthesis reactor that are liquid at reaction conditions. This is referred to as wax because it is a solid at 75 ° F. (24 ° C.) and 1 atmosphere (101 kPa) pressure. It must contain sufficient waxy material boiling above 1000 ° F. (538 ° C.) to produce the heavy hydrocarbon composition of the present invention. The waxy feed is typically dewaxed in one or more catalytic dewaxing stages where the feed is contacted with hydrogen and the dewaxing catalyst under dewaxing conditions. The iso-paraffins to n-paraffins ratios perform GC-FID for compositions containing molecules with up to 20 carbon atoms, and ¹³ C-NMR and GC for compositions containing molecules with 20 or more carbon atoms. Measured by performing a combination of -FID. Aromatics are determined by X-ray fluorescence (XRF) as described in ASTM standard D-2622. Sulfur is measured by XRF according to ASTM standard D-2622 and nitrogen is measured by syringe / injected oxidative combustion with chemiluminescence detection according to ASTM standard D-4629.

Catalysts useful in the hydrodeswaxing step include solid acid components, hydrogenation components and binders. Non-limiting examples of suitable catalyst components useful for hydrodeswaxing include, for example, ZSM-23, ZSM-35, ZSM-48, ZSM-57, ZSM-22, and SAPO, also known as theta-one or TON. Silica aluminophosphates, SSZ-32, zeolite beta, mordenite and rare earth metal ions, known as (eg, SAPO-11, 31 and 41), may be mentioned. Alumina and amorphous silica alumina are also useful.

As in the case of many other zeolite catalysts, it may be desirable to introduce a solid acid component with matrix materials known as binders that are resistant to the temperatures and other conditions used in the dewaxing process herein. Such matrix materials include active and inert materials and synthetic or natural zeolites, as well as inorganic materials such as clay, silica and / or metal oxides such as alumina. The latter may be natural or in the form of gelatinous precipitates, sols or gels, including mixtures of silica and metal oxides. The use of materials with active solid acid components, ie combined with them, can improve the conversion and / or selectivity of the catalyst herein. The inert material suitably acts as a diluent to control the amount of conversion in a given process so that the product can be obtained economically in turn without using speed or other means of controlling the reaction. Often crystalline silicate materials have been introduced into natural clays such as bentonite and kaolin. These materials, namely clays, oxides and the like, function in part as binders for catalysts. It is desirable to provide a catalyst with good crush strength, because in petroleum refining equipment the catalyst is often subject to rough handling, which is susceptible to breakdown into powdery materials that cause problems during processing.

Natural clays that can be mixed with the solid acid component include the kaolin class, including the sub-bentonite and montmorillonite, and kaolin commonly known as Dixie and Florida clays from McNami, Georgia, or And other substances whose main mineral constituents are halosite, kaolinite, dickite, nacrite or anoxite. Such clays can be originally mined or used as raw materials which are initially subjected to calcination, acid treatment or chemical modification.

In addition to the above materials, the solid acid component is not only porous matrix materials such as silica-alumina, silica-magnesia, silica-zirconia, silica-toria, silica-berilia, silica-titania, but also silica-alumina-toria, silica-alumina-zirconia , Ternary compositions such as silica-alumina-magnesia and silica-magnesia-zirconia. The matrix may be in the form of a cogel. Mixtures of these components can also be used. The relative proportions of the finely divided solid acid component and the inorganic oxide gel matrix vary widely, and the crystalline silicate content is in the range of about 1 to about 90 weight percent of the composite, more typically in the range of about 2 to about 80 weight percent. ZSM-48 is preferably used.

The hydrogenation component will comprise at least one Group VIII metal component, preferably at least one Group VIII precious metal component such as Pt and Pd. The precious metal concentration will range from about 0.1 to 5%, more typically from about 0.2 to 1% by weight of the metal, based on the total catalyst weight, including the ZSM-48 zeolite component and any binder used in the catalyst composite. Group VIII as referred to herein refers to Group VIII found in the Sargent-Weltz Periodic Table, copyrighted in 1968 by Sargent-Weltz Scientific Company.

The preparation of ZSM-48 (ZSM-48 zeolites include structurally equivalent EU-2, EU-11 and ZBM-30) is well known and is described, for example, in US patents the disclosure of which is incorporated herein by reference in its entirety. 4,397,827, 4,585,747 and 5,075,269 and EP 0 142 317. Other hydrodewaxing catalysts useful in the practice of the present invention include any of the well-known catalysts that are mostly dewaxed by isomerization rather than by decomposition or hydrocracking. Zeolites comprising 10 and 12 membered ring structures are particularly useful as dewaxing catalysts when combined with catalytic metal hydrogenation components. The hydrodewaxing reaction conditions used to prepare the hydrocarbon or heavy lubricating compositions of the present invention range from 450 to 750 ° F. (232 to 399 ° C.), 10 to 2,000 psig (69 to 13790 kPa) and 0.1 to 5.0 LHSV, respectively. Temperature, hydrogen partial pressure and space velocity. These conditions will more generally range from 500 to 700 ° F. (260 to 371 ° C.), 100 to 1000 psig (690 to 6895 kPa) and 0.5 to 3.0 LHSV, with pressures of 200 to 700 psig (1379 to 4827 kPa) being more typical. .

Example 1

In this example, the wax feed consists of a total of 430 ° F. (221 ° C.) waxy hydrocarbon fractions produced in a slurry Fischer-Tropsch hydrocarbon synthesis reactor comprising a titania supported rhenium-promoted non-mobile cobalt hydrocarbon synthesis catalyst. It became. The wax consisted of at least 90% by weight of n-paraffinic hydrocarbons and 26.2% by weight of 1000 ° F. (538 ° C.) fraction. Hydrogenwaxed with hydrogen in the presence of the ZSM-48 hydrodewaxing catalyst together with the Pt precious metal component to form isomers. The isomers were fractionated to remove 700 ° F- (371 ° C) hydrocarbons and residual 700 ° F + (371 ° C +) fractions, and then fractionated to remove and recover the 950 ° F + (510 ° C +) heavy lubricated isomer fraction. . This heavy isomer fraction was then further hydrodewaxed with hydrogen through the same ZSM-48 hydrodewaxing catalyst in a separate reactor to form a heavy hydrocarbon composition or a heavy lubricating base stock of the present invention. The hydrodewaxing conditions of the first and second reactors include temperatures of 586 ° F. (308 ° C.) and 616 ° F. (324 ° C.) and low hydrogen pressures of 250 psi (1724 kPa), respectively. These compositions, the properties of which are shown in the table below, had a kinematic viscosity of 13 and 15 cSt at 100 ° C.

The ZSM-48 hydrodewaxing catalyst in both reactors comprises 0.6% by weight of Pt as the hydrogenation component on the hydrogen form composite of ZSM-48 zeolite and alumina binder. The hydrogen form of the ZSM-48 zeolite was prepared according to the method of US Pat. No. 5,075,269, the disclosure of which is incorporated herein by reference. The Pt component was added by impregnation, followed by calcination and reduction using known methods.

Gas chromatography distillation (GCD) was performed using a high temperature GCD method variant of ASTM D-5307. The column consisted of a thin liquid phase of less than 0.2 micron and a single capillary column. An external specification consisting of a boiling point calibrant in the range of 5 to 100 carbon atoms was used. Using a temperature programmed injector and prior to injecting, the sample was slowly warmed using hot water. The boiling range was determined using this method and T5 and T95 GCD results. In the case of Phase Two Tec Instruments under the lubrication process, the cloud point value was measured using ASTM D-5773. Pour point was measured according to ASTM D-5950 for ISL Auto pour point measurement. In the following table the cloud point and pour point are given in ° C. Viscosity and viscosity index were measured according to ASTM protocols D-445 and D-2270, respectively.

Example 2

In this example, the wax feed was Paraflint C-80, a commercially available hydrotreated Fischer-Tropsch wax produced by Sasol in a fixed bed Fischer-Tropsch reactor from a mobile iron catalyst. . Untreated raw waxes contain relatively high levels of aromatic and aliphatic unsaturations, and heteroatom compounds, which are hydrotreated to produce paraffinic C-80 waxes. This solid wax is a distillation fraction having a viscosity in the range of 6 to 10 cSt at 100 ° C. and a nominal T5 boiling point of about 850 ° F. (454 ° C.). This was hydrogenated by hydrogen in the presence of a Pt / ZSM-48 catalyst similar to that used above in a single reactor but which had been sulfided. The hydrodeswax reaction pressure was 1000 psi (6895 kPa). The hydrodeswaxed product was fractionated by distillation to produce a heavy hydrocarbon composition of the present invention having a viscosity of 11 cSt at 100 ° C., the properties of which are also shown in the table below.

Comparative Example A

The present run is a nominal 700 to 950 ° F. (371 to 510 ° C.) isomers which are then further hydrogenated with hydrogen through the same ZSM-48 hydrodewaxing catalyst roll in separate separators to have a viscosity of 4 cSt at 100 ° C. Similar to Example 1 except forming a composition of the invention. The hydrodewaxing conditions of the first and second reactors included respective temperatures of 586 ° F. (308 ° C.) and 597 ° F. (314 ° C.) and low hydrogen pressure of 250 psi (1724 kP). This comparative composition is shown in the following table.

Comparative Example B

This was similar to Example 2 for the feed, catalyst and single hydrodeswaxing reactor. Two compositions having viscosities of 6 and 8 cSt at 100 ° C. were prepared by fractionating the hydrodewaxed product by distillation. Neither of these compositions is a composition of the present invention and is included in the table below for comparative purposes.

The microstructure of the composition in the table was analyzed by carbon-13 NMR spectrum. Samples were prepared at w / w concentrations of 20-25% in chloroform d-doped with 7.5 mg / ml Cr (acac) ₃ . Chemical shifts were referenced using TMS set to 0.0 ppm. The spectra were captured on a Varian Unity Plus 500 at 125.7 MHz carbon lamore frequency and had 8000 co-average transients per spectrum. All spectra were captured using a 90 ° excitation pulse on carbon, WALTZ-16 decoupling (over 0.8 second capture time) gated on protons, and a 6 second recycle delay. Sample preparation and data capture were performed at 50 ° C. Data acquisition parameters (chrome doping, mitigation delay, reverse gated decoupling) were chosen to ensure accurate and quantitative integration. Data capture, calculation, and reference are also made in US Pat. No. 6,090,989 in connection with the NMR technique.

Proton NMR analysis of the samples was performed on a 5 mm switchable probe and approximately 80 mg of the sample was dissolved in 1 gm chloroform-d. Sample preparation and data capture were performed on a Varian Unity Plus 500 at 50 ° C. Using a 90 ° excitation pulse, a 8.4 second abatement delay, and a 3.2 second capture time, a 64 co-average transient free induction delay was captured. In proton NMR no retardant was used.

Different data indicate that the heavy hydrocarbon compositions of the present invention (those having a viscosity of 11, 13 and 15 cSt) are heavy hydrocarbons in terms of their branching index (BI), and the proximity or branching proximity (CH ₂ > 4) of branching as a whole. When measured for the composition it was shown that (a) BI-0.5 (CH ₂ > 4) <15 and (b) BI + 0.85 (CH ₂ > 4) <45. In addition, the data showed that BI was typically less than 25 and branching proximity (CH ₂ > 4) was typically greater than 17 for the heavy hydrocarbon composition of the present invention.

The figure is a graph depicting BI and% CH ₂ > 4 derived from the NMR spectrum of the heavy hydrocarbon composition of the present invention, a comparison herein, and data of US Pat. No. 6,090,989, which includes other hydrocarbon compositions. The disclosure of US Pat. No. 6,090,989 is incorporated herein by reference in its entirety. The dark areas on the drawing define the NMR parameter zones of the heavy hydrocarbon composition of the present invention. Only heavy hydrocarbon compositions and PAO based raw materials of the present invention, preferably derived from Fischer-Tropsch synthesized waxy hydrocarbons, enter the parameter zone. Molecular compositions of PAO raw materials are typically in the case of compositions of the present invention, while (i) they do not contain hydrocarbon molecules with consecutive carbon atoms, and (ii) the percentage of hydrogen atoms from CH ₃ groups on the molecule is less than 15 It differs from the heavy hydrocarbon composition of the present invention in that it is greater than 20 and (iii) the percentage of hydrogen atoms from the CH group in the case of PAO feedstock is greater than 3, while in the composition of the invention it is typically less than 2.

Claims (20)

Kinematic viscosity measured by ASTM D-445 at 100 ° C., containing at least 95% by weight paraffin molecules of at least 90% by weight isoparaffin, containing hydrocarbon molecules having consecutive carbon atoms, and liquid at 100 ° C. Is greater than 8 cSt and has an initial boiling point of at least 850 ° F. (454 ° C.) and a terminal boiling point of at least 1000 ° F. (538 ° C.), the branching index (BI) measured by the percent of methyl hydrogen of the isoparaffinic hydrocarbon molecule. And branching proximity (CH ₂ > 4), measured by percent of repeating methylene carbon, which is at least 4 carbons removed from terminal groups or branches, is determined for the heavy hydrocarbon composition as a whole (a) BI-0.5 ( Heavy hydrocarbon composition wherein CH ₂ > 4) <15 and (b) BI + 0.85 (CH ₂ > 4) <45. The method of claim 1, A composition having a branching index (BI) of less than 24 and containing at least 95% by weight of hydrocarbon molecules having at least 30 carbon atoms. The method according to claim 1 or 2, Compositions with branching proximity (CH ₂ > 4) greater than 17. The method according to any one of claims 1 to 3, Less than half of the branches of isoparaffinic hydrocarbon molecules comprise two or more carbon atoms. The method according to any one of claims 1 to 4, A composition wherein less than 25% of the total number of carbon atoms in the isoparaffinic hydrocarbon molecule is present in the branch. The method according to any one of claims 1 to 5, A composition comprising at least 98% by weight of saturated paraffinic hydrocarbons wherein at least 90% by weight is an acyclic hydrocarbon and less than 5% by weight is a cyclic hydrocarbon. The method according to any one of claims 1 to 6, Less than 25% of the total number of branches comprises at least three carbon atoms. The method according to any one of claims 1 to 7, Less than 15% of the total number of branches comprises at least three carbon atoms. The method according to any one of claims 1 to 8, A composition having a terminal boiling point above 1050 ° F. (566 ° C.). The method according to any one of claims 1 to 9, A composition comprising at least 95% by weight hydrocarbon having at least 30 carbon atoms. The method according to any one of claims 1 to 10, A composition having a T5 boiling point of at least 900 ° F. The method according to any one of claims 1 to 11, Wherein less than 25% of the total number of carbon atoms in the isoparaffinic hydrocarbon molecule is present in the branch. The method according to any one of claims 1 to 12, Hydrogenated and optionally dehaze composition. The method according to any one of claims 1 to 13, A composition that is liquid at 75 ° F. (24 ° C.) and 1 atmosphere (101 kPa) pressure. The method according to any one of claims 1 to 14, A composition having a cloud point and pour point greater than 75 ° F. (24 ° C.) at 1 atmosphere (101 kPa) pressure, measured in ASTM D-5773 and ASTM D-5950, respectively. The method according to any one of claims 1 to 15, A composition that is a synthetic composition. 17. The method according to any of claims 1 to 16, as one or more of or as one or more of a heavy lubricating base material, a heavy white oil, a pharmaceutical oil, a carrier or a substrate for pharmaceutical formulations and as a component of a chemical and pharmaceutical manufacturing process. Use of the composition according to. Use of a composition according to any of claims 1 to 16 for reducing the pour point and cloud point of a heavy lubricating substrate raw material. A heavy lubricating base material comprising the composition according to any one of claims 1 to 16. A heavy lubricant comprising the heavy lubricant base material of claim 18 and at least one lubricant additive.