NL1026460C2 - Stable, moderately unsaturated distillate fuel blending materials prepared by hydroprocessing Fischer-Tropsch products under low pressure. - Google Patents

Description

Stable, moderately unsaturated distillate fuel blending materials prepared by hydroprocessing Fischer-Tropsch products under low pressure

Related applications 5

The present application is a "continuation in part" of U.S. application 09/999667, "DistiUate Fuel Blends from Fischer Tropsch Products with, Improved Seal Swell Properties" filed on October 19, 2001, the contents of which are incorporated herein by reference. . The present application is also related to U.S. Patent Application 10/464546 (file number 005950-779) with the title "Highly Paraffinic, Moderately Aromatic Distillate Fuel Blend Stocks Prepared by Low Pressure Hydroprocessing or Fischer Tropsch Products", filed with it.

Field of the invention

The invention relates to low sulfur content distillate fuels comprising a Fischer-Tropsch distillate fuel blending material having excellent stability and a moderate content of unsaturated compounds.

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BACKGROUND OF THE INVENTION

Distillate fuel obtained from the Fischer-Tropsch process is highly paraffinic and has excellent combustion properties and a very low sulfur content. This makes Fischer-Tropsch products ideally suited for use as a fuel where environmental problems are important. Fuels with good or preferably excellent stabilities are always desired and stable fuels can be produced by hydrotreating or hydrocracking Fischer-Tropsch products. However, conventional hydrotreating and hydrocracking processes require the use of expensive hydrogen to saturate olefins and to convert oxygenation products to paraffins.

Stable diesel fuels with low sulfur levels and high cetane indices are desired because of their low emissions and good behavior in an engine. Similarly, stable jet engine fuels with low sulfur levels and high smoke points are desired. Fuels of this type can be prepared from Fischer-Tropsch products. The preparation of distillate fuels from Fischer-Tropsch processes is known.

Although highly paraffinic, Fischer-Tropsch products also contain olefins, alcohols, and trace amounts of other compounds that may cause stability problems. Typically, hydroprocessing is used to saturate essentially all olefins and remove oxygenation products. Hydro weathering, however, requires the use of expensive hydrogen gas and expensive installations that are designed to be operated under high pressure.

ASTM specifications for diesel fuel (D985) describe stability measurements for the respective fuels. For diesel fuel, ASTM D6468, "Standard Test Method for High Temperature Stability of Distillate Fuels", has been considered as a standard test method for a diesel fuel and this test can provide a good measure of fuel stability. Undiluted hydrotreated and hydrocracked Fischer-Tropsch products usually have excellent stabilities in this test. ASTM specifications for jet engine fuel A and A-1 (D1655) describe the application of the JFTOT test ASTM D3241 with strokes at 260 ° C. Larger stabilities are often desired. For example, the February 2003 guidelines of the Colonial Pipeline's Quality Assurance (section 3.19.1 on page 3B-33) require that fungible aviation kerosene has a JFTOT stability of 275 ° C or higher. This requirement of greater stability provides some compensation for the decrease in product stability during transport. The Coordinating Research Council's Handbook of Aviation Fuel Propers, third edition, May 1988, describes on page 102 (Table 25 10) that several military jet engine fuels require higher stability requirements than commercially available Jet A: JP-9 and JP-10 a stability of 300 ° C or higher, JP-7 and TS require a stability of 335 ° C or higher. Very stable jet engine fuels are generally desired

In addition to conventional stability measurements (thermal and storage), studies by Vardi et al (J. Vardi and BJ Kraus, "Peroxide Foimation in Low Sulfur Automotive Diesel Fuels", February 1992, SAE report 920826) describe how fuels are significant amounts of peroxide can develop during storage and how these peroxides can attack elastomers of the fuel system (O-rings, hoses, etc.) 1 026460-3. The formation of peroxides can be enjoyed by infrared spectroscopy, chemical methods or by the attack on elastomer samples. As described by Vardi et al., Fuels can become unstable with regard to the formation of peroxide if its sulfur content is lowered to low amounts by hydroprocessing. Vardi et al also describe how compounds such as tetralin can cause fuels to become unstable with respect to peroxide formation, while polycyclic aromatic compounds such as naphthalenes can improve stability. Vardi et al explain that aromatics are effective as natural antioxidants and note that natural peroxide inhibitors such as sulfur compounds and polycyclic aromatics can be removed.

In the wake of Vardi's weave, two recent Exxon patents describe how the peroxide stability of highly paraffinic Fischer-Tropsch. products is unacceptable but can be improved by adding sulfur compounds from other mixing components. However, since sulfur compounds increase the 1S sulfur emissions, this approach is undesirable

By way of example, U.S. Pat. No. 6162956 describes a Fischer-Tropsch distillate fraction mixed with either a crude distillate fraction of a gas field condensate or a condensate fraction subjected to moderate hydrotreatment to obtain a stable, inhibited fraction. distillate fuel. The fuel is described as a blending material useful as a distillate fuel or as a blending component for a distillate fuel, comprising: (a) a Fischer-Tropsch distillate comprising a Ce-700 ° F fraction and (b) a distillate of a gas field condensate comprising a Ce-700 ° F fraction, wherein the sulfur content of the blending material is ^ 1 wt-ppm. This patent describes that distillate fuels obtained via Fischer-Tropsch processes are hydrotreated to remove unsaturated materials, e.g. olefins, and most, if not all, oxygenation products. This patent further describes that the products contain less than or equal to 0.5% by weight of unsaturated compounds (olefins and aromatics).

Similarly, U.S. Patent No. 6180842 describes a Fischer-Tropsch distillate fraction mixed with either a crude fresh condensate fraction or a moderately hydrotreated fresh condensate to obtain a stable inhibited distillate fuel. The fuel is described as a blending material useful as a distillate fuel or as a blending component for a distillate fuel, comprising (a) a Fischer-Tropsch distillate comprising a Cs-700 ° F stream and a sulfur content of less than 1 % by weight and (b) 1-40% by weight of a fresh distillate comprising a Ce-700oF stream; wherein the sulfur content of the blending material is ^ 2 wt-ppm. It is noted in this patent that while there is no standard for the peroxide content of fuels, it is generally accepted that stable fuels have a peroxide number of less than about 5 ppm, preferably less than about 4 ppm and more preferably lower than about 1 ppm. This value has been tested after 4 weeks in an oven at 60 ° C. The patent shows that Fischer-Tropsch products with a peroxide number of 24.06 have unacceptable stability after 4 weeks.

It is described that the Fischer-Tropsch products in U.S. Patent No. 6180842 comprise> 80 wt%, preferably> 90 wt%, more preferably> 95 wt% paraffins, with an iso / normal ratio of 0, 1 to 10, preferably 0.3 to 3.0, more preferably 0.7 to 2.0; sulfur and nitrogen each in an amount less than 1 ppm, preferably less than 0.5, more preferably minda: than 0.1 ppm; ^ 0.5% by weight of unsaturated compounds (olefins and aromatics), preferably ^ 0.1% by weight; and less than 0.5 weight percent oxygen on an anhydrous basis, preferably less than about 0.3 weight percent oxygen, more preferably less than 0.1 weight percent oxygen, and most preferably no oxygen. U.S. Patent No. 6180842 discloses that the Fischer-Tropsch distillate is essentially free of acids.

U.S. Patent No. 5689031 demonstrates that low-sulfur diesel olefins contribute to the formation of peroxide. See fuels C and D in Example 7 and Figure 2. U.S. Patent No. 5,658,931 describes that the solution to the peroxide tendency is to limit the olefin content by hydrotreating the lightest olefin fraction. However, this solution requires the use of expensive hydrogen gas.

Accordingly, there is a need in the art for low sulfur distillate fuels and distillate fuel blends with a satisfactory stability that can be obtained from the products of a Fischer-Tropsch process, thereby reducing the use of expensive hydrogen. . This invention provides such distillate fuels and distillate fuel blending materials and the processes for their production.

1 026460-5

Summary of the invention

The present invention relates to a distillate fuel comprising a Fischer-Tropsch distillate fuel blending material. The Fischer-Tropsch distillate fuel blending material comprises unsaturated compounds in an amount between 2 and 20% by weight, paraffins in an amount of 80% by weight or more, sulfur in an amount less than 1 ppm and peroxide precursors in such an amount that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C, and the Fischer-Tropsch distillate fuel mixing material has a cetane index higher than 60 .

In another embodiment, the present invention relates to a Fischer-Tropsch diesel fuel blending material. The Fischer-Tropsch diesel fuel blending material comprises unsaturated compounds in an amount between 2 and 20% by weight, paraffins in an amount of 90% by weight or more, sulfur in an amount less than 1 ppm and peroxide precursors in such an amount that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C. The unsaturated compounds comprise less than 20% by weight of polycyclic aromatics, preferably less than 10% by weight of polycyclic aromatics and even more preferably less than 5% by weight of polycyclic aromatics. Preferably the unsaturated compounds include both olefins and aromatics and most preferably the olefins are present in amounts greater than or equal to 1% by weight. Features of the diesel fuel blending material include a cetane index higher than 60, a percentage of reflectance according to ASTM D6468 at 150 ° C greater than 65% when measured after 90 minutes.

In yet another embodiment, the present invention relates to a Fischer-Tropsch jet engine fuel blending material. The Fischer-Tropsch jet engine fuel mixing material comprises unsaturated compounds in an amount between 2 and 10% by weight, paraffins in an amount of 90% by weight or more, sulfur in an amount of less than 1 ppm and peroxide precursors in such an amount that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C. The unsaturated compounds comprise less than 20% by weight of polycyclic aromatics, preferably less than 10% by weight of polycyclic aromatics and even more preferably less than 5% by weight of polycyclic aromatics. Features of the jet fuel mixing material include a smoke point of 30 mm or higher and a pass assessment in ASTM D3241 (JFTOT method) at 260 ° C for 2.5 hours.

In a further embodiment, the present invention relates to a process for preparing a highly paraffinic, moderately saturated, distillate fuel blending material. The method comprises converting syngas into a feed obtained via Fischer-Tropsch by means of a Fischer-Tropsch process and hydroprocessing the feed obtained via Fischer-Tropsch. A highly paraffinic, moderately unsaturated distillate fuel blending material is recovered. The highly paraffinic, moderately unsaturated distillate fuel-blending material contains between 2 and 20% by weight of unsaturated compounds, less than 1 ppm sulfur and peroxide precursors in such an amount that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C. The hydroprocessing conditions include a temperature of 600-750 ° F, a pressure lower than 1000 psig and a liquid space velocity per hour higher than 0.25 hours.

In yet a further embodiment, the present invention relates to a distillate fuel comprising a Fischer-Tropsch distillate fuel blending material, wherein the Fischer-Tropsch distillate fuel blending material is prepared according to a method of converting syngas into a Fischer-Tropsch-obtained feed Fischer-Tropsch process; hydroprocessing the feed obtained via Fischer-20 Tropsch at a temperature of 525-775 ° F, a pressure lower than 1000 psig and a liquid space velocity per hour higher than 0.25 hours "1; recovering a Fischer Tropsch distillate fuel blending material includes The Fischer-Tropsch distillate fuel blending material comprised of between 2 and 20 wt.% Unsaturated compounds, less than 1 ppm sulfur and peroxide precursors in an amount such that less than 5 ppm peroxides are formed after store four weeks at 60 ° C.

In a further embodiment, the present invention relates to a method for operating a diesel engine, which comprises using a Fischer-Tropsch diesel fuel blending material as a diesel fuel wherein the Fischer-Tropsch diesel fuel blending material is unsaturated compounds in an amount between 2 and 20 % by weight, parafins in an amount of 90% by weight or more, sulfur in an amount less than 1 ppm and peroxide precursor in an amount such that less than 5 ppm peroxides are formed after four 1026460-7 'weeks of storage at 60 ° C. The unsaturated compounds comprise less than 20% by weight of polycyclic aromatics, preferably less than 10% by weight of polycyclic aromatics and even more preferably less than 5% by weight of polycyclic aromatics. Preferably the unsaturated compounds include both olefins and aromatics and most preferably the olefins are present in amounts greater than or equal to 1% by weight. The characteristics of the diesel fuel mixing material include a cetane index higher than 60, a percentage of reflectance according to ASTM D6468 at 150 ° C greater than 65% when measured after 90 minutes.

In yet another embodiment, the present invention relates to a method for operating a jet engine comprising the use of a Fischer-Tropsch jet engine fuel mixing material as jet engine fuel, wherein the Fischer-Tropsch jet engine fuel mix material is unsaturated compounds in an amount between 2 and 10 % by weight, paraffins in an amount of 90% by weight or more, sulfur in an amount less than 1 ppm and peroxide precursors in an amount such that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C C. The unsaturated compounds comprise less than 20% by weight of polycyclic aromatics, preferably less than 10% by weight of polycyclic aromatics and even more preferably less than 5% by weight of polycyclic aromatics. Characteristics of the jet notor fuel mixing material include a smoke point of 30 mm or higher and a pass assessment in ASTM D3241 (JFTOT method) at 260 ° C for 2.5 hours.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is an illustration of a process for preparing a distillate fuel blending material of the present invention.

Detailed description of the invention According to the present invention, it has been found that highly paraffinic, moderately unsaturated distillate fuel blending materials with a low sulfur content can be produced which have excellent stability. The distillate fuel blending materials can be prepared according to a process which is a Fischer-1 026460-8

Tropsch synthesis and hydroprocessing under conditions where a moderate amount of unsaturated compounds is formed or retained in the product. Therefore, the present invention relates to highly paraffinic, moderately unsaturated distillate fuel blending materials with a low sulfur content that have excellent stability and to distillate fuels comprising these blending materials. The highly paraffinic, moderately unsaturated Fischer-Tropsch distillate fuel blends with low sulfur content can be mixed with other blending materials to provide a distillate fuel or can be undiluted in the absence of other blending materials with optional addition of small amounts of additives such as fuel can be used in an engine

For the purposes of the present invention, the following definitions are used herein:

The term "unsaturated compounds" means a hydrocarbon containing one or more double or triple bonds, preferably, for example, an aromatic and / or olefinic functionality.

The term "olefins" means an unsaturated straight or branched hydrocarbon with at least one double bond (i.e., an olefin).

The term "aromatics" means an unsaturated, cyclic, and flat hydrocarbon with an uninterrupted cloud of electrons containing an odd number of B electron pairs.

A "distillate fuel mixing material" is a material that is mixed with other distillate fuel mixing materials to provide a distillate fuel, in particular a diesel or jet engine fuel, as defined herein. The mixing material itself does not necessarily meet the specifications for the fuel in question, but preferably the combination of mixing materials obtained satisfies. Jet engine fuel mixing materials are combined with other jet engine fuel mixing materials, and optionally additives, to provide jet engine fuel. Similarly, diesel fuel blending materials are combined with other diesel fuel blending materials, and optionally additives, to provide diesel fuel.

An "aromatic blending material" is a blending material that contains aromatics in an amount greater than or equal to 50% by weight, preferably greater than or equal to 75% by weight, and most preferably greater than or equal to 90% by weight % includes If a pure aromatic product is used as an aromatic mixing material, analysis of the aromatics content is not necessary. If the aromatic mixing material comprises aromatics and other hydrocarbons, a modified version of ASTM D6550 (Standard test method for determining the olefin content of gasolines by supercritical liquid chromatography (SFQ) can be used to determine the aromatics content. An aromatic mixing material can also be used. are mixed with a Fischer-Tropsch distillate fuel blending material to increase the aromatics content of the Fischer-Tropsch distillate fuel blending material Examples of aromatic blending materials include commercially available pure aromatics (e.g., benzene, alkyl benzenes and the like); aromatics those obtained from conventional petroleum products, aromatics obtained from reforming Fischer-Tropsch reformable products, and the like.

The cetane index was determined according to ASTM D4737-96a (2001) Standard test method for calculated cetane index according to the comparison with four variables.

Conventional petroleum products include products obtained from crude petroleum.

A "petroleum blending material" is a blending material comprising conventional petroleum products Petroleum blending materials may consist of the vapor overhead streams from distilling crude petroleum or refined products and the residual fuels which are the non-vaporizable residual portion.

Obtained via a Fischer-Tropsch process means that the relevant food, mixing material or product comes from or is produced at any stage with a Fischer-Tropsch process.

A "Fischer-Tropsch distillate fuel blending material" is a blending material that originates from or is produced at any stage by a Fischer-Tropsch process. A Fischer-Tropsch distillate fuel blending material can be blended with other distillate fuel blending materials to provide a distillate fuel, in particular a diesel or jet engine fuel. The mixing material itself 30 does not necessarily have to meet the specifications for the respective fuel, but the resulting combination of mixing materials does. Fischer-Tropsch distillate fuel blending materials include Fischer-Tropsch diesel fuel blending materials and Fischer-Tropsch jet fuel blending materials. As stated above, the Fischer-Tropsch distillate fuel blending materials can be mixed with other blending materials to provide a distillate fuel, or the Fischer-Tropsch distillate fuel blending materials can be diluted directly in the absence of other blending materials with only the optional addition of small 5 amounts of additives are used as fuel in an engine

A distillate fuel is a material that contains hydrocarbons with boiling points between approximately 60 ° F to 1100 ° F. Specific fuels such as naphtha, jet fuel, diesel fuel, kerosene, aviation gasoline, fuel oil and mixtures thereof fall within the broad category of distillate fuels.

10 A diesel fuel is a material that is suitable for use in diesel engines. Preferably a diesel fuel meets at least one of the following specifications: • ASTM D975 - "Standard Specification for Diesel Fuel Oils" • European Quality CEN 90 15 · Japanese Fuel Standards JIS K 2204 • The 1997 guidelines of The United States National Conference on Weights and Measures (NCWM) for first quality diesel fuel • The United States Engine Manufacturers Association's recommended guidelines for first quality diesel fuel (FQP-1A) 20 A diesel fuel can consist of a combination of mixing materials or a single mixing material in the absence of other mixing materials with only the possible addition of small amounts of additives.

A jet engine fuel is a material that is suitable for use in turbine engines in aircraft or other applications. Preferably a jet engine fuel meets at least one of the following specifications: • ASTMD1655, • DEF STAN 91-91 / 3 (THIRD 2494), TURBINE FUEL, AVIATION, • KEROSENE TYPE, JET A1, NATO CODE: F- 35, • International Air Transportation Association (IATA) Guidance Materials for 30 Aviation, fourth edition, mart 2000

A jet engine fuel can consist of a combination of mixing materials or a single mixing material in the absence of other mixing materials with only the possible addition of small amounts of additives.

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A Fischer-Tropsch diesel fuel mixing material is a mixing material that is suitable for use in a diesel engine. The Fischer-Tropsch diesel fuel mixing material can be mixed with other mixing materials to provide a diesel fuel or can be used in the absence of other mixing materials with only the optional use of small amounts of additives.

A Fischer-Tropsch jet engine fuel mixing material is a mixing material that is suitable for use in turbine engines in aircraft or other applications. The Fischer-Tropsch jet engine mixing material can be mixed with other mixing materials to provide a jet engine fuel or can be used in the absence of other mixing materials with only the optional addition of small amounts of additives.

A highly paraffinic, moderately unsaturated distillate fuel blending material is a distillate fuel blending material that contains more than 70% by weight of paraffins, preferably 80% by weight or more of paraffins and most preferably 90% by weight or 15% of paraffins and 2 to 20% by weight % unsaturated compounds, preferably 2 to 15% by weight unsaturated compounds and most preferably 5 to 10% by weight unsaturated compounds. Preferably, the unsaturated compounds include both olefins and aromatics, and most preferably, the olefins are present in an amount greater than or equal to 1% by weight. A highly paraffinic, moderately unsaturated distillate fuel blending material with a low sulfur content contains less than 1 ppm sulfur. Preferably, the highly paraffinic, moderately unsaturated distillate fuel blending material is a Fischer-Tropsch distillate fuel blending material.

A "Fischer-Tropsch-derived feed" or "Fischer-Tropsch feed" is a feed derived from or produced at any stage by a Fischer-Tropsch process. In the methods of the present invention, a feed obtained through Fischer-Tropsch can be mixed during processing with a petroleum blending material to provide a mixed stream.

Syngas is a mixture that includes both hydrogen and carbon monoxide. In addition to these species, water, carbon dioxide, unconverted light hydrocarbon feed, and various contaminants may also be present.

"Hydrocarbonaceous" or "hydrocarbon" means a compound or substance containing hydrogen and carbon atoms, but which may include heteroatoms such as oxygen, sulfur or nitrogen.

"Peroxide precursors" means those components in a hydrocarbon product or feed that form peroxides in the hydrocarbon product and / or cause the formation of peroxides in the hydrocarbon product. The peroxide precursors can be identified and the amount of the peroxide precursors can be measured by storing the hydrocarbon product in an oven for 4 weeks at 60 ° C. The peroxide precursors are identified by the formation of peroxides and the amount of the peroxide precursors can be measured based on the amount of peroxides formed.

According to the present methods, the peroxide content of samples is measured using a method for measuring the accumulation of peroxides as described in ASTM D3703. For example, a sample of 4 15 ounce is placed in a brown bottle and aerated for 3 minutes. After the test period, a small amount of the sample is then tested according to ASTM D3703, with the exception that iso-octane is used instead of freon. Tests confirmed that the replacement of solvents for environmental reasons had no significant effect on the measurement results. The formation of peroxides can also be measured by infrared spectroscopy, chemical methods or by the attack on elastomeric samples.

A modified version of ASTM D6550 (Standard Test Method for the Determination of the Olefin Content of Gasolines by Supercritical Fluid Chromatography (SFC)) was used to determine the type of groups in the feeds and products. The modified method uses a 3-point calibration standard to quantify the total amount of saturated compounds, aromatics, oxygenation products (polar) and olefins. Solutions of the calibration standard were prepared using the following compounds: undecane, toluene, n-octanol and dodecene. An external standard method was used for the quantification and the detection limit for aromatics and oxygenation products is 0.1% by weight and for olefins is 1.0% by weight. The instrument conditions are described in ASTM D6550.

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A small amount of the fuel sample was injected into a series of two chromatography columns connected in series and transported using supercritical carbon dioxide as the mobile phase. The first column was packed with large surface area silica particles. The second column 5 contained large surface area silica particles loaded with silver ion

Two switch valves were used to feed the different classes of components through the chromatographic system to the detector. In a forward-flow mode, saturated compounds (normal and branched alkanes and cyclic alkanes) were passed through both columns to the detector, while olefins were captured on the silver-laden column and the aromatics and oxygenation products remained on the silica column. Aromatic compounds and oxygenation products were then eluted from the silica column to the detector in a backwash manner. Finally, the olefins from the silver-laden column were backwashed to the detector.

A flame ionization detector (F1D) was used for quantification. The calibration was based on the surface of the chromatographic signal of the saturated compounds, aromatics, oxygenation products and olefins, relative to standard reference materials, which is a known mass percentage of total saturated compounds, aromatics, oxygenation products and olefins, corrected for density, contain. The total mass that was collected was 100% +/- 3% and was normalized to 100% for convenience.

The polycyclic aromatics (PNA) content of the products was determined according to ASTM D5186-99 Standard Test Method for Determinadone or Aromatic Content and Polynuclear Aromatic Content of Diesel Fuels and Aviation Turbine Fuels by Supercritical Fluid Chromatography.

The paraffin content of the product was determined by supercritical liquid chromatography (SFC) analysis, using the following algorithm. The SFC analysis provides assays of the aromatics, olefins, oxygenation products, and saturated compounds. Saturated compounds in this analysis are a combination of paraffmen and naphthenes (i.e. cycloparaffins).

Thus 1026460-14

Paraffins = Saturated compounds (SFC) - Naphthenes

However, it was found that naphthenes were not present in significant amounts (less than 10% of the saturated compounds) in the products of the present invention. Thus, saturated compounds from the SFC analysis can usually be taken as a good and suitable measure of the paraffin content of the products of the invention.

To verify that naphthenes are not present in significant amounts, the naphthen content was determined independently by GC-MS. GC-MS 10 mentions olefins and cycloparafins as a combined sum because they have the same ratio of hydrogen to carbon in their structures and the technique cannot distinguish between them. If GC-MS mentions the combined sum of the olefins and cycloparafins as insignificant, then it can be concluded that the naphthenes are present in only insignificant amounts. However, if GC-MS states that the sum is significant, the amount of naphthenes can be determined by subtracting the olefin content (as determined according to SFC) from the combined GC-MS sum to provide the naphthenes.

Naphthenes = (Sum of the naphthenes and olefins according to GC-MS) - (Alkenes according to SFC) 20

The naphthenes can then be subtracted from the content of saturated compounds (as determined according to SFC) to provide a good appropriate measure of the paraffin content according to the first comparison. If the naphthen content determined in this way is lower than zero, it is stated as zero and zero is used in the calculation of the paraffins. So in this case the paraffins are the same as the SFC-saturated compounds.

In the GC-MS test, deuterium-labeled standards were used to quantify alkanes, olefins, alcohols, and acids. Selected deuterium-labeled compounds were added as internal standards to the sample of interest. The mixture of sample and standards was treated with trimethylsilyl (TMS) reagent to form the TMS derivative, followed by GCMS analysis. The mass spectrometer is a Hewlett-Packard bench top mass spectrometer coupled to an HP GC with a non-polar column of 60 meters. The normal alkanes and branched alkanes were all quantified using deuterium-labeled normal alkanes. Alkenes, alcohols and acids were all quantified using the corresponding deuterium-labeled compounds.

The paraffin content of the highly paraffinic, moderately unsaturated blending materials of the present invention is at least 70% by weight, preferably 80% by weight or more and most preferably 90% by weight or more. Because of its high paraffin content, the highly paraffinic, moderately unsaturated distillate fuel blending materials of the present invention have excellent combustion properties. Typical combustion properties of the blending materials of the present invention include smoking points higher than 25 mm, preferably higher than 30 mm, and cetane indices higher than 60, preferably higher than 65. The paraffins consist of a mixture of normal and isoparaffin fins, wherein the ratio of iso / normal paraffins in the fuel is between 0.3 and 10. Higher levels of isoparaffins are preferred if the blending material is intended for use in cold climates (Jet Al or diesel for use in arctic regions).

The content of unsaturated compounds of the mixing materials according to the present invention is between 2 and 20% by weight, preferably between 2 and 15% by weight, and most preferably between 5 and 10% by weight. The unsaturated compounds of the blending materials include minimal amounts of polycyclic aromatics. Preferably, the unsaturated compounds comprise less than 25% by weight of polycyclic aromatics, preferably less than 20% by weight of polycyclic aromatics, more preferably less than 10% by weight of polycyclic aromatics and even more preferably less than 25% by weight of polycyclic aromatics aromatics. Preferably, the unsaturated compounds include both olefins and aromatics, and most preferably, the olefins are present in amounts greater than or equal to 1% by weight.

Fuels comprising the highly paraffinic, moderately unsaturated blending materials of the present invention preferably meet at least a specification for either diesel or jet engine fuel. The fuels may consist of a combination of blending materials or the highly paraffinic, moderately unsaturated blending material in the absence of other blending materials with only the optional addition of small amounts of additives. The highly paraffinic, moderately unsaturated blending materials and fuels comprising this blending material exhibit at least an acceptable, and usually excellent, stability. For example, the percent reflection of diesel fuels comprising the highly paraffinic, moderately unsaturated blending materials, such as Measured according to ASTM D6468 at 150 ° C, higher than 65% if measured after 90 minutes, preferably higher than 65% if measured after 180 minutes and more preferably higher than 99% if measured after 180 minutes. Jet engine fuels comprising the highly paraffinic, moderately unsaturated blending materials have a pass assessment in ASTM D3241 (JFTOT process) at 260 ° C for 2.5 hours, preferably a pass assessment in ASTM D3241 (JFTOT process) at 270 ° C for 2.5 hours and more preferably a pass assessment in ASTM D3241 (JFTOT method) at 300 ° C for 2.5 hours. A pass assessment corresponds to a pipe rating lower than 3 (code 3) and a pressure drop over a filter of less than 25 mm Hg.

The blending materials of the present invention, and fuels comprising the blending materials, exhibit acceptable stability according to conventional stability tests and acceptable peroxide resistance. The blending materials form less than 5 ppm peroxides after 4 weeks in an oven at 60 ° C, preferably less than 4 ppm peroxides after 4 weeks in an oven at 60 ° C and more preferably less than 1 ppm peroxides after 4 weeks store in an oven at 60 ° C. Accordingly, the blending materials comprise peroxide precursors in an amount such that the fuel forms less than 5 ppm peroxides after being stored for 4 weeks at 60 ° C in an oven, preferably less than 4 ppm peroxides forms after 4 weeks at 60 ° C in a oven and more preferably less than 1 ppm peroxides forms after 4 weeks in an oven at 60 ° C. The amount of peroxide-25 precursors is measured by storing in an oven for 4 weeks at 60 ° C. The amount of peroxide precursors can be determined based on the amount of peroxides that are formed. The formation of peroxides can be measured by infrared spectroscopy, chemical methods or by attack on elastomer samples.

The mixing materials of the present invention, and fuels comprising the mixing materials, usually have a low sulfur content (<1 ppm) and preferably a low nitrogen content (<1 ppm). Therefore, the emissions of oxides from heteroatoms into the environment are reduced. Accordingly, the mixing materials and fuels comprising the mixing materials are desired as environmentally friendly.

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Fischer-Tropsch

The blending materials of the present invention can be prepared from Fischer-Tropsch products and hydroprocessed under conditions in which a moderate amount of unsaturated compounds is formed. Preferably, the mixing materials of the present invention are prepared at least in part from Fischer-Tropsch products.

In Fischer-Tropsch chemistry, syngas is converted into liquid hydrocarbons by contact with a Fischer-Tropsch catalyst under reactive conditions. Typically, methane and optionally heavier hydrocarbons (ethane and heavier) can be passed through a conventional syngas generator to provide synthesis gas. Generally, synthesis gas contains hydrogen and carbon monoxide and it may include small amounts of carbon dioxide and / or water. The presence of sulfur, nitrogen, halogen, selenium, phosphorus and arsenic contaminants in the syngas is undesirable. Therefore, and depending on the quality of the syngas, it has the precursor to remove sulfur and other contaminants from the feed before the Fischer-Tropsch chemistry is performed. Means for removing these contaminants are known to those skilled in the art. For example, ZnO protection beds are preferred for removing sulfur contaminants. Means for removing other contaminants are known to those skilled in the art. It may also be desirable to purify the syngas for the Fischer-Tropsch reactor to remove carbon dioxide produced during the syngas reaction and additional sulfur compounds that have not yet been removed. This can be done, for example, by contacting the syngas with a moderately alkaline solution (e.g. aqueous potassium carbonate) in a packed column.

In the Fischer-Tropsch process, contacting a synthesis gas comprising a mixture of H 2 and CO with a Fischer-Tropsch catalyst produces liquid and gaseous hydrocarbons under suitable reaction conditions of temperature and pressure . In general, the Fischer-Tropsch reaction can be carried out at temperatures of about 149 to 371 ° C (300 to 700 ° F), preferably about 204 to 228 ° C (400 to 550 ° F); pressures of about 0.7 to 41 bar (10 to 600 psia), preferably 2 to 21 bar (30 to 300 psia); and catalyst space rates of about 100 to about 10,000 cm 3 / g / hour, preferably about 300 to 3,000 cm 3 / g / hour.

Fischer-Tropsch processes can be categorized as either a Fischer-Tropsch process at high temperature or a Fischer-Tropsch process at low temperature. The process conditions and the products that are mainly formed during the two processes are different.

A high temperature Fischer-Tropsch process is generally conducted at temperatures higher than 250 ° C, preferably at or higher than 350 ° C. Fischer-Tropsch processes at a high temperature provide substantially lower molecular weight olefinic products, generally in the range of C3 to Cs, preferably propylene to pentenes. High temperature Fischer-Tropsch products can also include significant amounts of aromatics. High temperature Fischer-Tropsch products can be subjected to aromatics saturation processes, including reforming processes. The olefinic products of the high temperature Fischer-Tropsch process are usually further processed by oligomerization and hydrogenation steps to produce a highly branched isoparaffinic product. The products of the Fischer-Tropsch process at high temperature can be processed in such a way that they meet the specifications for gasoline. The products of high temperature Fischer-Tropsch processes usually have cetane indices of about 55 as the products are highly branched. An example of a high temperature Fischer-Tropsch process is the Synthol process used by SASOL, as described in "High Yield High Quality Diesel from Fischer Tropsch Process, Dry, M.E., Chem. S.A., February 1984.

Jet engine fuels have also been produced according to Fischer-Tropsch processes at high temperature, olefin oligomerization and hydrogenation. A high temperature Fischer-Tropsch process for producing jet engine fuels is described in "Qualification of SASOL Semi-Synthetic Jet As Commercial Jet Fuel", SwRl-8531, November 1997. The jet engine fuels prepared according to a Fischer-Tropsch high temperature process, as described in the reference, do not contain aromatics or unsaturated compounds. The literature states that the thermal stability breakpoint, or JFTOT breakpoint, for blends of high-temperature jet engine fuel via Fischer-Tropsch with conventional petroleum jet engine fuel is higher than 300 ° C. Hence, the thermal stability, or JFTOT, breaking point of such semi-synthetic blends is significantly higher than the requirement of the 260 ° C specification. See "Qualification of SASOL Semi-Synthetic Jet A-1 Commercial Jet Fuel", Moses, Stavinoha and Roets, South West Research Institute Publication SwRI-8531, November 5, 1997.

Researchers working with high-temperature Fischer-Tropsch products and mixtures of high-temperature Fischer-Tropsch products and petroleum-derived products have not noticed any stability problems.

A low temperature Fischer-Tropsch process is operated at temperatures below 250 ° C and produces a heavier product. The heavier product of a Fischer-Tropsch process at low temperature usually contains essentially wax. The products of the Fischer-Tropsch process at low temperature are usually subjected to a hydrotreatment so that they have acceptable peroxide stability, as shown in U.S. Patent No. 6180842. Therefore, the products of Fischer-Tropsch processes are produced at low temperature. usually refined by hydroprocessing operations such as hydrotreating and hydrocracking to provide stable fuels that meet the desired specification. The products of low temperature Fischer-Tropsch processes are essentially linear and even after hydrocracking, these products contain fewer branches than products prepared by a high temperature Fischer-Tropsch process. Fewer branches in the products of Fischer-Tropsch processes at low temperature provide higher cetane indices for these products compared to the products of the high temperature processes, which have more branches. The low temperature Fischer-Tropsch products usually have cetane indices higher than 60 and preferably higher than 70.

The Fischer-Tropsch process for preparing the distillate fuel blending materials of the present invention is a low-temperature Fischer-Tropsch process. Examples of conditions for carrying out Fischer-Tropsch type reactions at low temperature are known to those skilled in the art.

The products can vary from Ci to C200S with the largest part in the range of C5-C100 +. The reaction can be carried out in a variety of reactor types, such as fixed bed reactors containing one or more catalyst beds, slurry reactors, fluidized bed reactors, or a combination of different types of reactors. Such reaction processes and reactors are known and documented in the literature. In Fischer-Tropsch suspension processes, which is a preferred process in the practice of the invention, superior heat (and mass) transfer characteristics are used for the highly exothermic synthesis reaction and paraffinic hydrocarbons with a relatively high molecular weight can be used. produced if a cobalt catalyst is used. In a slurry process, a syngas comprising a mixture of H 2 and CO is bubbled upwards as a third phase through a slurry in a reactor comprising a particulate hydrocarbon synthesis catalyst of the Fischer-Tropsch type that is dispersed and suspended in a suspending liquid comprising hydrocarbon products of the synthesis reaction which are liquid under the reaction conditions. The molar ratio of hydrogen to carbon monoxide can vary roughly from about 0.5 to 4, but is more usually in the range of about 0.7 to 2.75 and preferably from about 0.7 to 2.5.

Suitable Fischer-Tropsch catalysts include one or more Group Vm catalytic metals, such as Fe, Ni, Co, Ru, and Re. In addition, a suitable catalyst may contain a promoter. Thus, a preferred Fischer-Tropsch catalyst comprises effective amounts of cobalt and one or more of the elements Re, Ru, Pt, Fe, Ni, Th, Zr, Hf, U, Mg and La on a suitable inorganic support material, at for core a material comprising one or more refractory metal oxides. In general, the amount of cobalt present in the catalyst is between about 1 and about 50 percent by weight of the total catalyst composition. The catalysts may also contain basic oxide promoters, such as TiO2, La2O3, MgO and TiO2, promoters such as ZrO2, noble metals (Pt, Pd, Ru, Rh, Os, Ir), coin metals (Cu, Ag and Au) and other transition metals such as Fe, Mn, Ni and Re. Support materials, including alumina, silica, magnesium oxide, and titanium oxide, or mixtures thereof, may be used. Preferred supports for cobalt-containing catalysts include titanium dioxide. Useful catalysts and their preparation are known and illustrative, but non-limiting, examples can be found, for example, in U.S. Patent No. 4,566,863.

Certain catalysts are known to provide chain growth probabilities that are relatively low to moderate and the reaction products include a relatively high content of low molecular weight olefins (C2-8) and a relatively low content of waxes having a low molecular weight. high molecular weight (C304) Certain other catalysts are known to provide relatively high chain growth probabilities and the reaction products include a relatively low content of low molecular weight olefins (C2-8) and a relatively high content of high molecular weight waxes ( C304). Such catalysts are known to those skilled in the art and can easily be obtained and / or prepared.

The products of low temperature Fischer-Tropsch reactions generally include a light reaction product and a wax-like reaction product. The wax-like reaction product (ie, the wax fraction) comprises hydrocarbons boiling at a temperature higher than about 600 ° F. (e.g. vacuum gas oil up to heavy paraffins), largely in the range of C 4, with decreasing amounts up to C 10 · Both the light reaction product and the wax-like product are essentially paraffinic. The wax-like product generally comprises more than 70% by weight of normal paraffins and often more than 80% by weight of normal paraffins.

15

Hvdro processing

Hydro-processing is generally known to those skilled in the art and includes processes such as hydrotreating, hydrocracking, hydrogenating, catalytic dewaxing or combinations of these processes. Preferably, the hydroprocessing operation of the present invention accomplishes various purposes in one or more reactors, most preferably a single reactor. The aims of hydroprocessing include reducing, or preferably completely removing, heteroatoms such as nitrogen and sulfur. While in conventional hydroprocessing, unsaturated compounds are usually removed or their contents substantially reduced, in hydroprocessing according to this invention, at least a portion of the unsaturated compounds is retained or aromatics are formed; and yet a distillate product is obtained which has acceptable stability. Furthermore, hydroprocessing can increase the ratio of iso / normal paraffins in the distillate product. Hydroprocessing can also increase the production of distillate product by converting heavy species. Finally, the hydroprocessing can also be carried out under conditions where a moderate amount of unsaturated compounds is formed or maintained.

1026460-22

By hydroprocessing under conditions where unsaturated compounds are formed or retained, the net hydrogen consumption in the hydroprocessing process can be reduced or eliminated. Although the addition of hydrogen is necessary to begin the hydroprocessing process, if the formation of aromatics is large enough, the amount of hydrogen produced during the process may exceed the amount of hydrogen supplied to the process. Therefore, there may be a net production of hydrogen from the hydroprocessing of the present invention, i.e. the net hydrogen consumption is less than zero.

The produced hydrogen can be used for a variety of purposes in a gas-to-liquid (GTL) installation. These objectives include hydrotreating Fischer-Tropsch currents to reduce or eliminate olefins and / or hetero atoms. Furthermore, the produced hydrogen can be reacted with CO2 produced in the GTL process or extracted from a CO2-15 containing gas source to reduce CO2. The product of the CO2-H2 reaction can be CO or a Fischer-Tropsch product and the reaction can be carried out in the syngas generator. The produced hydrogen can also be used in fuel production, as a fuel component that does not form CO2 emissions. The produced fuel can be used for generating process heat, producing electrical energy and / or distilling / purifying water.

Typical temperatures for hydroprocessing Fischer-Tropsch products for retaining unsaturated compounds or generating aromatics are 525-775 ° F, preferably 575-725 ° F. Typical pressures for this operation are lower than 1000 psig, preferably lower than 600 psig, and most preferably between 200 and 500 psig. Typical liquid space velocities per hour (LHSV) for this operation are higher than 0.25 hours, preferably between 0.5 and 1.5 hours. Conventional hydroprocessing catalysts for this operation include catalysts for conventional hydroprocessing operations (described below) or catalysts for hydroisomerization dewaxing, preferably combinations of catalysts for hydroprocessing operations and hydroisomerization dewaxing are used since this combination is less expensive and also a simultaneous reduction of the pour point of makes the product possible.

1 026460-23

A conventional hydroprocessing catalyst can be used to generate aromatics and to preserve unsaturated compounds. Hydro-processing catalysts which are particularly suitable for generating aromatics are bifunctional catalysts which contain both a hydrogenation function and an acid S function. The aromatic-forming hydroprocessing catalyst, unlike, for example, a conventional hydrotreating catalyst, has an acidic function because hydrotreating catalysts typically comprise a non-acidic carrier such as alumina.

The acid function is preferably based on a mixture of at least two metal oxides with different valencies. The preferred mixture of metal oxides includes SiO 2 and Al 2 O 3; or Al 2 O 3, S 1 O 2 and P 2 O 5. The mixture of metal oxides can be prepared in such a way as to provide a high dispersion of at least a portion of the metal oxides between each other, for example a dispersion of S1O2 and Al2O3 on an atomic scale instead of separate phases of S1O2 and Al2O3 . The presence of individual phases of S1Q2 and Al2O3 can be determined by an XRD examination. When all oxides are present as separate phases, the performance of the catalyst decreases. Examples of the acid function consisting of mixed metal oxides are zeolites, crystalline SAPOs and co-precipitated S2O2 - Al2O3.

Although halogens, in particular fluoride in the form of a fluorinated aluminum oxide, can be used as an acidic function in a hydroprocessing catalyst, halogens are not preferred because they are slowly stripped from the catalyst and can lead to corrosion of the reactor vessel

The hydrogenation function in an aromatics-forming hydroprocessing catalyst comprises a metal. Suitable hydrogenation metal and include Group VI metals, such as Mo and / or W, and Group Vm metals, such as Ni or Co. These are present on the catalyst in sulfurized form. Preferably the hydrogenation metal is a noble metal and more preferably it is selected from the group of Pt, Pd and mixtures thereof. These may be sulfurized, but their use in non-sulfurized form is preferred.

Catalysts useful in hydroprocessing operations are known in the art. Suitable catalysts include noble metals from group VIIA (according to the rules of the International Union of Pure and Applied Chemistry from 1975), such as platinum or palladium on an aluminum oxide or silicon-containing matrix, and group νίΠΑ and group VIB, such as nickel molybdenum, cobalt-molybdenum, nickel-tungsten or nickel-tin on an aluminum oxide or silicon-containing matrix. The non-noble metal (such as nickel-molybdenum) hydrogenated metals are usually present in the final catalyst composition as oxides, or more preferably or possibly, as sulfides, if such compounds are simply formed from the metal in question. Preferred non-noble metal catalyst compositions contain more than about 5 weight percent, preferably about 5 to about 40 weight percent molybdenum and / or tungsten, and at least about 0.5, 10 and generally about 1 to about 15 weight percent nickel and / or cobalt, determined as the corresponding oxides. The noble metal (such as platinum) catalyst may contain more than 0.01 percent metal, preferably between 0.1 and 1.0 percent metal. Combinations of noble metals can also be used, such as mixtures of platinum and palladium.

The matrix components include some that have acid catalytic activity.

Those possessing activity include amorphous silica-alumina or may be a zeolietic or non-zeolietic crystalline molecular sieve. Examples of suitable matrix molecular sieves include zeolite Y, zeolite X and the so-called ultra-stable zeolite Y and zeolite Y with a high structural ratio of silica: alumina. Suitable matrix materials can also be synthetic or natural substances as well as inorganic materials such as clay, silica and / or metal oxides such as silica-alumina, silica-magnesium oxide, silica-zirconia, silica-thorium oxide, silica-berylium oxide, silica-titanium oxide as well as temary compositions such as silicon dioxide-alumina-thorium oxide, silica-alumina-zirconia, silica-alumina-magnesium oxide and silica-magnesium-oxide-zirconia. The latter may either occur naturally or be in the form of gelatinous precipitates or gels comprising mixtures of silica and metal oxides. Naturally occurring clays that can be formulated with the catalyst include those from the montmorillonite and kaolin families. These clays can be used in the crude state as they were originally mined or they can be initially subjected to calibration, acid treatment or chemical modification. More than one catalyst type can be used in the reactor.

As mentioned above, hydroprocessing is generally known to those skilled in the art and includes processes such as hydrotreating, hydrocracking, hydrogenating, catalytic dewaxing or combinations of these processes. By hydroprocessing according to the present invention, the feed obtained through Fischer-Tropsch is worked up by performing an operation selected from the group consisting of reducing the sulfur, nitrogen and oxygen content in the feed; reducing the content of olefins in the diet; increasing the ratio of iso / minimal paralfins in the product to between 0.3 and 10; increasing the production of distillate fuel product by converting heavy species into the feed; and combinations thereof.

Conventional hydrotreating conditions vary over a wide range. Typical pressures for this operation are lower than 1000 psig, preferably lower than 600 psig, and most preferably between 200 and 500 psig. Typical liquid space rates per hour (LHSV) for this operation are higher than 0.25 hours * 1, preferably between 0.5 and 2.0 hours * 1. Hydrogen recirculation rates are usually higher than 50 standard cubic feet per barrel of oil (SCF / Bbl) and are preferably between 1000 and 5000 SCF / Bbl. The temperatures range from about 300 ° F to about 750 ° C and preferably range from 450 ° F to 600 ° F.

Hydrocracking can be performed by conventional methods known to those skilled in the art. Hydrocracking is usually a process of breaking down larger carbon molecules into smaller ones. This can be accomplished by contacting the respective fraction or combination of fractions with hydrogen in the presence of a suitable hydrocracking catalyst at temperatures in the range of about 316 to 482 ° C (600 to 900 ° F), preferably 343 to 454 ° C (650 to 850 ° F) and pressures in the range of about 13 to 272 atm (200 to 4000 psia), preferably 34 to 204 atm (500 to 3000 psia), using space rates that are based on the hydrocarbon feed of about 0.1 to 10 hours * 1, preferably 0.25 to 5 hours * 1. Hydrocracking is generally used to reduce the size of the hydrocarbon inolecules, hydrogenate olefin bonds, hydrogenate aromatics, and remove trace amounts of hetero atoms. Suitable catalysts for hydrocracking operations are known in the art and include sulfurized catalysts. Sulphurized catalysts may include amorphous silica-alumina, alumina, tungsten, and nickel.

The hydrogenation conditions are known in the industry and include temperatures higher than ambient temperature and pressures higher than atmospheric pressure. Preferred conditions for the hydrogenation include a temperature between 300 and 800 ° F, most preferably between 400 and 600 ° F, a pressure between 50 and 2000 psig, most preferably between 100 and 500 psig, a flow dust space velocity per hour (LHSV) between 0.2 and 10 hours * 1, most preferably between 1.0 and 3.0 hours * 1 and a gas flow between 500 and 10,000 SCFB, most preferably between 1000 and 10 hours 5000 SCFB.

The catalysts used for hydrogenation are those commonly used in hydrotreating, but non-sulfurized catalysts containing Pt and / or Pd are preferred, and it is preferred to have the Pt and / or Pd on a support, such as aluminum oxide, silicon dioxide, silicon dioxide-aluminum-oxide or carbon. The preferred support is silica-alumina.

Catalytic dewaxing consists of two main classes - usually hydro dewaxing and hydroisomerization dewaxing; hydroisomerization dewaxing can be further subdivided into partial and complete hydroisomerization dewaxing. All classes include passing a mixture of a waxy hydrocarbon stream and hydrogen over a catalyst containing an acidic component to convert the normal and slightly branched isoparaffins in the feed into other non-waxy species and thereby forming of a lubricant base material product with an acceptable pour point (lower than about + 10 ° F or -12 ° C). Typical conditions for all classes include temperatures of about 400 to 800 ° F, pressures of about 200 to 3000 psig, and space rates of about 0.2 to 5 hours * 1. The method chosen for dewaxing a feed usually depends on the product quality and the wash content of the feed, with conventional hydro-dewaxing generally being preferred for low wash feed. The method of dewaxing can be accomplished by the choice of the catalyst. The general topic is discussed by Avilino Sequeira, in Lubricant Base Stock and Wax Processing, Marcel Dekker Ine., Pages 194-223.

1 026460-27

Determination of the class of the dewaxing catalyst from conventional hydro-dewaxing, partial hydroisomerization dewaxing and full hydroisomerization dewaxing can be done using the n-hexadecane isomerization test as described by Santilli et al. In U.S. Patent No. 5,228,958. When measured at a 96% n-hexadecane conversion under the conditions described by Santilli et al., Conventional hydro-dewaxing catalysts exhibit a selectivity for isomerized hexadecans of less than 10%, hydroisomerization dewaxing catalysts show a selectivity for isomerized hexadecans of more than or equal to 10%, partial hydroisomerization dewaxing catalysts have a selectivity for isomerized hexadecans of more than 10% to less than 40% and complete hydroisomerization dewaxing catalysts have a selectivity for isomerized hexadecans of more than or equal to 40% , preferably more than 60% and most preferably more than 80%.

Conventional hydro-dewaxing is defined for the purposes of this document as a catalytic dewaxing process using a conventional hydro-dewaxing catalyst. In conventional hydro-dewaxing, the pour point is lowered by selectively cracking the wax molecules, essentially to smaller paraffins boiling between propane and about octane. Because this technique converts the wax into less valuable by-products, it is essentially useful for dewaxing oils that do not contain a large amount of wax. Wax-like oils of this type are often found in petroleum distillate from moderately wax-like crude oils (Arabic, North Slope, etc.). Catalysts useful for conventional hydro-dewaxing are usually 12-ring zeolites and 10-ring zeolites. Zeolites of this class include ZSM-5, ZSM-11, ZSM-22, ZSM-23, ZSM-35, and Mordenite. Common hydrotassing catalysts are preferred for cracking as compared to another paraffin converting process. This is demonstrated by applying the n-hexadecane isomerization test according to Santilli et al., Where conventional hydrotassing catalysts exhibit a selectivity for isomerized hexadecane products of less than 10%. In addition to the zeolites, metals can be added to the catalyst, primarily for reducing fouling. Representative process conditions, yields, and product properties for conventional hydro-dewaxing are described, for example, in U.S. Patent Nos. 4176050 to Chen et al., 4181598 to Gillespie et al., 4,222,855 to 1,026,460-28

Pelrine et al., 4229282 to Peters et al., And 4211635 to Chen. These patents are to be regarded as incorporated herein for all purposes. Process conditions are further described and explained by Sequeira, in the section entitled "The Mobil Lube Dewaxing Process," pages 198-204 and references therein, J.D.

5 Hargrove, G.J. Elkes and A.H. Richardson, Oil and Gas J., p. 103.15 January 1979.

Hydroisomerization dewaxing is defined for the purposes of this document as a catalytic dewaxing process using a hydroisomerization dewaxing catalyst. In hydroisomerization dewaxing, at least a portion of the wax is converted by isomerization to non-wax-like isoparaffins, while at the same time the cracking conversion is reduced. When conventional hydro-dewaxing and hydromerization dewaxing are compared with respect to the same feed, the conversion of wax to non-wax-like isoparaffins during hydroisomerization dewaxing provides benefits of reducing the yield of less valuable by-products, increasing the yield to lubricating oil and forming an oil with a higher VI and a higher oxidation and thermal stability. Hydroisomerization dewaxing uses a dual functional catalyst consisting of an acid component and a metal component. Both components are required for carrying out the isomerization reaction. Common metal components are platinum or palladium, with platinum usually being used. The choice and amount of the metal in the catalyst is sufficient to achieve more than 10% isomerized hexadecane products in the test described by Santilli et al. As the selectivity for hexadecane isomers according to the Santilli 40 test %, the catalyst is a complete hydroisomerization dewaxing catalyst. Because hydroisomerization dewaxing converts the wax to isoparaffins boiling in the range of the lubricant base material, this is useful for dewaxing oils containing a large amount of wax. Wax-like oils of this type are obtained from slag washing of solvent dewaxing processes and distillates of highly wax-like crude oils (Minas, Altamont, etc.) and products from the Fischer-Tropsch process.

Partial hydroisomerization dewaxing is defined for the purposes of this document 30 'as a catalytic dewaxing process using a partial hydroisomerization dewaxing catalyst. In partial hydroisomerization dewaxing, a portion of the wax is isomerized to isoparaffins using catalysts that can selectively isomerize paraffins, but only if the conversion of the 1 026460-29 was at relatively low values (usually below 70%) is kept. At higher conversions, the conversion of the wax by cracking becomes significant and the loss of yield of the lubricant base material becomes uneconomical. The acid catalyst components useful for partial hydroisomerization dewaxing include amorphous silica-alumina, fluorinated alumina and 12-ring zeolites (such as Beta, Y-zeolite, L-zeolite). Because the conversion of the wax is incomplete, partial hydroisomerization dewaxing must be supplemented with an additional dewaxing technique, usually solvent dewaxing. The wax recovered from a solvent dewaxing operation after partial hydroisomerization dewaxing can be recycled to the partial hydroisomerization dewaxing step.

Representative process conditions, yields and product properties for partial hydroisomerization dewaxing are described, for example, in U.S. Patent Nos. 50,49536 to Belussi et al. And 49,43672 to Hamner et al. These patents should be contemplated for all purposes as incorporated herein. Process conditions are further described and explained in EP 0582347 from Perego et al., EP 0668342 from Eilers et al., PCT WO 96/26993 from Apelia et al., And PCT WO 96/13563 from Apelian et al.

Full hydroisomerization dewaxing is defined for the purposes of this document as a catalytic dewaxing process using a full hydroisomerization dewaxing catalyst. In full hydroisomerization dewaxing, full hydroisomerization dewaxing catalysts are used that can achieve a high level of conversion of wax while accepting acceptable selectivities for isomerization are preserved. The acid catalyst components useful for partial hydroisomerization dewaxing include 1-dimensional 10-ring molecular sieves (such as ZSM-23, SSZ-32, Theta-1, ZSM-22, SAPO-11 and SAPO-41). Because the conversion of the wax can be complete, or at least very high, this process usually does not need to be combined with additional dewaxing processes to produce a lubricant base material with an acceptable pour point. Representative process conditions, yields and product properties for fully hydroisomerization dewaxing. are described, for example, in U.S. Patent Nos. 5,113,538 to Miller, 5,224,666 to Miller, 5,228,958 to Santilli et al .; 5082986 from Miller, and 5723716 from Brandes et al .; wherein the contents of each of these as a whole are incorporated herein by reference.

1 026460-30

Catalytic dewaxing

Conventional Hydroisomerization dewaxing hydro dewaxing

Partial Complete hydroisomerization hydroisomerization dewaxing dewaxing

Temperature, ° F 400-800

Pressure, psig 200-3000 LHSV, hourly 0.2-5.0 n-C 16 selectivity for> 40, isomerized preferably> 60, products at a <10 10-40 with most conversion of 96% preferably> 80

Typical acid ZSM-5, ZSM-11, Silicon dioxide-ZSM-23, SSZ-32, components ZSM-22, ZSM alumina, Theta-1, ZSM-22, 35, Mordenite fluorinated SAPO-11 and alumina SAPO-41 Beta , Y and L zeolites

Conventional metal - Optionally, often Pt or Pd, with Pt or Pd, with components absent, preference Pt preferred Pt

People with petroleum oil materials The distillate fuel of the present invention may consist of a combination of blending materials or the distillate fuel may consist of a Fischer-Tropsch distillate fuel blending material in the absence of other blending materials with only the optional addition of small amounts of additives. Accordingly, the distillate fuels may comprise a Fischer-Tropsch distillate fuel blending material mixed with a petroleum blending material. In a mixture of blending materials, the distillate fuel preferably comprises 1 to 95% by weight of Fischer-Tropsch blending material and 5 to 99% by weight of petroleum blending material. More preferably, the distillate fuel comprises 5 to 75% by weight of Fischer-Tropsch blending material and 25 to 95% by weight of petroleum blending material. Even more preferably, the distillate fuel comprises 10 to 50% by weight of Fischer-Tropsch blending material and 90 to 50% by weight of petroleum blending material.

In addition, in the process for preparing a highly paraffinic, moderately unsaturated blending material, the Fischer-Tropsch feed can be mixed with a petroleum blending material at any stage of the process, as long as a highly paraffinic, moderately unsaturated Distillate fuel mixing material according to the present invention is provided. By way of example, a petroleum blending material can be mixed with a feed obtained via Fischer-Tropsch before hydroprocessing, after hydroprocessing but before removing polycyclic aromatics, or after removing polycyclic aromatics but for use as a distillate fuel Preferably, the petroleum blending material is mixed with the Fischer-Tropsch feed prior to hydroprocessing and the resulting mixed stream is hydroprocessed. When the Fischer-Tropsch feed is mixed with a petroleum blending material, the resulting mixture preferably comprises 1 to 95% by weight of Fischer-Tr storage feed and 99 to 5% by weight of petroleum blending material. More preferably, the mixture comprises 5 to 75% by weight of Fischer-Tropsch feed and 95 to 25% by weight of petroleum blending material. Even more preferably, the mixture comprises 10 to 50% by weight of Fischer-Tropsch feed and 50 to 90% by weight of petroleum blending material.

Removal of polycyclic aromatics

In order to satisfy the desired low polycyclic aromatics content in the highly paraffinic, moderately unsaturated blending material, the product stream from the hydroprocessing operation can be further treated to remove polycyclic aromatics. Options for selectively removing polycyclic aromatics from the product stream while leaving the desired mono-aromatics selectively include hydrotreating and adsorption.

The most preferred operation for removing polycyclic aromatics from the product stream is selective hydrotreating. The reaction conditions for selective hydrotreating do not vary much from the hydroprocessing reaction conditions described above. The reaction conditions for selective hydrotreating include low temperatures (lower than 750 ° F, preferably lower than 700 ° F, most preferably lower than 600 ° F), high pressures (higher than 250 psig, preferably higher than 350 psig, most preferably higher than 500 psig) and short contact times (LHSV less than 5 hours -1, preferably less than 5 hours 3, and most preferably less than 2 hours * 1). Preferred catalysts for this selective hydrotreating contain Pt, Pd and combinations thereof. By selective hydrotreating, the content of polycyclic aromatics becomes at least 50% by weight, preferably at least 75% by weight and most preferably at least 90% by weight, and the content of unsaturated compounds by 10 is less than 50% by weight %, preferably less than 35% by weight and most preferably less than 20% by weight.

The removal of polycyclic aromatics from the product stream can also be achieved by adsorption on an oxide support, preferably an oxide support with a moderate acidity (an acid clay such as montmorillonite or attapulgite). The temperatures for adsorption should be lower than 200 ° F, preferably lower than 150 ° F. Polycyclic aromatics can also be extracted with a solvent such as n-methyl pyrrolidone, phenol or furfural.

Additives 20

The distillate fuel and the distillate fuel blending material may include additives commonly used for diesel or jet engine fuels. A description of diesel fuel additives that can be used in the present invention is as described in the Chevron Corporation, Technical Review Diesel Fuels, pages 55-64 (2000) and a description of jet engine fuel additives that can be used in the present invention is as described in Chevron Corporation, Technical Review Aviation Fuels, pages 27-30 (2000). In particular, these additives may include, but are not limited to, antioxidants, lubricant additives, pour point lowering agents, and the like. The additives are added to the fuels and mixed materials in a small amount, preferably less than 1% by weight.

1 02 6460-33

Illustrative embodiment

The figure shows a method for preparing a highly paraffinic, moderately unsaturated distillate fuel blending material according to the present invention. In Figure 1, a feed (10) obtained via Fischer-Tropsch at low temperature is hydroprocessed in a hydroprocessing unit (100) to which hydrogen (20) is supplied. The hydroprocessing conditions include a temperature of 600-750 ° F, a pressure lower than 1000 psig and a liquid space velocity per hour higher than 0.25 hours. The hydroprocessing product (30) is a highly paraffinic, moderately unsaturated distillate fuel blending material containing between 2 and 20 weight percent of unsaturated compounds and peroxide precursors in such an amount that less than 5 ppm peroxides is formed after four weeks store at 60 ° C. The hydroprocessing can give hydrogen (60), which can be used in other processes such as hydrotreating, CO2 reduction, and fuel production. Optionally, the highly paraffinic, moderately unsaturated distillate fuel blending material (30) can be further treated to remove polycyclic aromatics (70) in a processing unit (200).

The following examples are provided to illustrate the invention and are not to be construed as limiting the scope of the invention.

20

Examples Example 1 A light Fischer-Tropsch wax at low temperature (Table I) was hydrocracked over a sulfurized nickel-tungsten / silica-alumina catalyst (a conventional hydroprocessing catalyst), LHSV 1 hour -1, 1000 psig, 685 ° F and 6.3 MSCF / bbl. At these conditions, the conversion at a temperature below 650 ° F was 80.4% by weight. The liquid product was fractionated at about 350 ° F and about 675 ° F to give a diesel blending material fraction. The yields and properties of the diesel mixing material are given in Table Π.

1 026460 - 34

Table I.

Diet inspections of light FT wax Specific gravity, API 42.5 Nitrogen ppm 3.2

Sim. Dist., LV%, ° F

ST / 5 728/771 1Ö / 3Ö 789/811 5Ö 839 70/90 858/885 95 / EP 898/943

Table Π

Hydrocracking of light FT wax over Ni-W-SiCVAkOa at LHSV for 1 hour 1.685 ° F, 1000 psig and 6.3 MSCF / Bbl Conversion <650 ° F, wt% 80.4

Yield,% by weight

C 1 -C 2 O 3) 3 0 5 5 6 6 C 5 180 0 17/77 180-350 ° F 20 * 85 350-650 ° F 37 ^ 51 650 ° F + 19/7 ~ 9M9 "350-675 ° F Properties

% By weight of food 52.9

Specific weight, API 50.7

Viscosity, 40 ° C, cSt 2.631

Cloud point, ° C -26 SFC analysis,% by weight

Aromatics 0.3

Olefins 0.8

Oxygenation products <0.1 1026460-35

Saturated compounds 98.9 PNA aromatics, wt% not detected

Cetane index 75.9

Refractive index @ 20 ° C 1.4342

Density, g / ml @ 20 ° C 0.7745

Molecular weight 253

Types of carbon according to ndM,% by weight P / N / A 100/0/0 D2887 Dist.,% By weight, eF

SI / 5 288/342 / 3 / 368/448 50 "523 7/9 0 594/673 95 / EP 697/743

The lower detection limit of PNA by supercritical liquid chromatography (SFC) was 0.5% by weight. Thus, undetected values are smaller than this amount. By operating under these conditions, only 0.35 percent aromatics were produced and 0.8 percent by weight olefins were retained as a result of the usual high-pressure operation. The paraffin content of this sample is equal to the content of saturated compounds (98.9). The ndM analysis, which is suitable for non-olefin-containing samples, indicates the absence of naphthenic carbon structures.

10

Example 2

The same feed as in Example 1 was hydrocracked over a sulfurized 3/1 layered bed of the same catalyst as in Example 1 over a Pt / SAPO-11 catalyst bound with 15% by weight alumina. The Pt / SAPO-11 catalyst is a complete hydroisomerization dewaxing catalyst. The conditions were the same as in Example 1, i.e. a total LHSV of 1.0 hour * 1.1000 psig, 685 ° F and 6.3 MSCF / bbl H 2. The conversion at a temperature below 650 ° F was 74.6% by weight. The product was fractionated at about 350 ° F and about 650 ° F to give a diesel blending material fraction. Yields and properties of the diesel mixing material are given in Table ΙΠ. As determined according to ASTM D6468, the diesel mixing material was very stable. The aromatic content in the diesel mixing material was 0.1% by weight and the olefin content was 0.3% by weight as a result of the usual high-pressure processing and the use of Pt as a catalytic metal. The paraffin content was 99.6 because wet toes are absent as determined by GC-MS, and supported by ndM analysis. The cetane index was very high (73.8) and the cloud point very low (-57 ° C).

Table ΙΠ

Hydrocracking of light FT wax over 3/1 Ni-W-SiOa-AbQj / Pt-SAPO-11 at LHSV 1 hour 1.685 ° F, 1000 psig and 6.3 MSCF / Bbl Conversion <650 ° F, wt. % 74.6

Yield, wt% C 1 -C 2 "δ [δ 8 C 3 -C 4 Ti6

Cs-180 ° F 13 ^) 2 180-350 ° F 15.7 350 350-650 ° F "40.97 650 ° F + 25.59" 95.36 350-650 ° F Properties

% By weight of food 43.1

Specific weight, API 51.3

Viscosity, 40 ° C, cSt 2.206

Cloud point, ° C -57

Alkenes + nattenes,% by weight (GC-MS) not detected PNA aromatics,% by weight not detected SFC analysis,% by weight

Aromatics 0.1

Olefins 0.3

Oxygenation products <0.1

Saturated compounds 99.6 1 026460-37

% reflection, ASTM D6468 @ 150 ° C

1.5 hours 99.7 3.0 hours 99 °

Cetane index 73.8

Refractive index @ 20 ° C 1.4318

Density, g / ml @ 20 ° C 0.7699

Molecular weight 239 D2g87 Dist>% by weight> SI75 314/352 IQ / 3Ö 370/433 5Ö ~ 496 70/90 549/606 95 / EP 629/676

Example 3

Example 2 was repeated, but with a total pressure in the reactor of 500 psig and a reactor temperature of 680 ° F. The conversion at a temperature below 650 ° F was 63.5% by weight. The product was fractionated at about 350 ° F and about 590 ° F to give a diesel blending material fraction. Yields and properties of the diesel mixing material are given in Table IV. As determined according to ASTM D6468, the diesel mixing material was very stable. The aromatic content in the diesel mixing material was 2.3% by weight. The cetane index was quite high (69.1) and the cloud point very low (-50 ° C).

Table IV

Hydrocracking of light FT wax over 3/1 Ni-W-SKVAbOs / Pt-SAPO-11 at LHSV 1 hour · 1.680 ° F, 500 psig and 6.3 MSCF / Bbl Conversion <650 ° F, wt% 63, 5

Yield,% by weight

Ci-C2 Ö23 CVQ 1053 C5-180 ° F 13 ^ 98 1 026460- 38 180-350 ° F 15.63 350-650 ° F 23.72 650 ° F + 36.75 "9ÖÖ 350-590 ° F Properties

% By weight of food 19.1

Specific weight, API 51.1

Viscosity, 40 ° C, cSt 1.94

Cloud point, ° C -50 PNA aromatics, wt% not detected

% reflection, ASTM D6468 @ 150 ° C

1.5 hours ~ 99J

3.0 hours 99J

Cetane index 69.1

Refractive index @ 20 ° C 1.4323

Density, g / ml @ 20 ° C 0.7704

Molecular weight 224

D2887 Dist.,% By weight, ° F

ST / 5 316/350, 10/30 366/415 50 "468 7Ö / 9Ö! 519/572 95 / EP 591/643

Example 4

A low temperature FT wash hydrated at 700-1000 ° F (Table V) was hydrocracked over the same layer bed catalyst system of Example 2. The conditions included a total LHSV of 1.0 hour, a reactor pressure of 300 psig 680 ° F for the upper catalyst and 690 ° F for the lower catalyst and 6.3 MSCF / bbl H * The conversion at a temperature below 650 ° F was 58.2% by weight. The product was fractionated at about 300 ° F and about 650 ° F to give a diesel blending material fraction. Yields and properties of this diesel mixing material are given in Table VL. As determined according to ASTM D6468, the diesel mixing material was very stable. The aromatic content in the diesel mixing material was 4.3% by weight, the olefin content was 1.0% by weight and the content of oxygenation products was 0.5% by weight. The paraffins are equal to the saturated compounds (94.2%) because no significant amounts of the sum of olefins and wettenes were detected with the GC-MS technique. The cetane index was high (67.6) and the cloud point was -44 ° C.

Table V

Feed inspections of 700-1000 ° F hydrotreated FT wax Specific gravity, API 42.3 Sim. Dist, LV%, ° F

ST75 691/804 10/30 824/884 "5" 9-9 70/90 940/974 95 / EP 991/1031

Table VI

Hydrocracking of 700-1000 ° F hydrotreated FT wash over 3/1 Ni-W-SiO 2 -Al 2 O 3 / Pt-SAPO-11 at LHSV1 hour · 1.680 ° F, 300 psig and 6.3 MSCF / Bbl

Conversion <650 ° F,% by weight 58.2

Yield,% by weight

C3 -C4 AJS

C5-180 ° F £4 £ 3 180-350 ° F 15 ^ 53 350-650 ° F ~ 23 ^ 2 650 ° F + "41 ^ C5 + 95.7 350-650 ° F Properties 1026460- 40

% By weight of food 31.1

Specific weight, API 50.1

Viscosity, 40 ° C, cSt 2.027

Cloud point, ° C -44

Nattenes + olefins,% by weight (GC-MS) not detected SFC analysis,% by weight

Aromatics 4.3

Olefins 1.0

Oxygenation products 0.5

Saturated compounds 94.2 PNA aromatics, wt% 0.5

% reflection, ASTM D6468 @ 150 ° C

1.5 hours 99 ^ 2 3.0 hours 99 ^ 2

Cetane index 67.6

Refractive index @ 20 ° C 1.4348

Density, g / ml @ 20 ° C 0.7771

Molecular weight 196

Types of carbon according to ndM,% by weight P / N / A 92.40 / 5.01 / 2.59 D2887 Dist,% by weight, ° F

ST / 5 266/300 10/30 325/396 50 "472 70/90 561/645 95 / EP 667/698

The diesel blend material of Example 4 exhibited excellent stability, as measured for 180 minutes at 150 ° C according to ASTM D6468, just like the diesel blend materials of Examples 2 and 3, with results higher than 99%. The polycyclic aromatic content of the diesel blending material of Example 4 was 0.5% by weight - less than 10% by weight of the total content of unsaturated compounds (5.3%).

1026460-41

Example 5

A Fischer-Tropsch wash at low temperature and a light Fischer-Tropsch condensate at low temperature (Table VD) were processed on conventional hydroprocessing catalysts. 168 cm 3 / hour of the wash and a recycle liquid were hydrocracked over 126 cm 3 of a sulfurized NiW / acidic amorphous SiO 2 -Al 2 C> 3 catalyst. 106 cm 3 / h of the light condensate was mixed with the hydrocracker effluent and the mixture was hydrotreated over 68 cm 3 of a sulfurized NiMo / non-acid alumina catalyst. The effluent from the hydrotreating device was distilled to obtain gas, naphtha, distillate fuel blending materials and the recycle liquid. The operating conditions) yields and product properties are summarized in Table VIII. The hydrocracking reactor is referred to as Rx 1 and the hydrotreating reactor as Rx 2.

Table VII Properties of Fischer-Tropsch feeds

Fischer-Tropsch-Light Fischer-Tropsch-Fischer-Tropsch wax condensate wax

Nutrition of Example 5 5 6

Specific weight, ° API 40.3 53.5

Nitrogen, ppm 1.27 2.36 <0.25

D2887 Dist,% by weight, ° F

St / 5 451/573 91/206 441/545 /Ö / 30 623/725 253/345 587/694 5Ö 79Ö "434 786 70/90 870/973 519/625 880/1009 95 / EP 1010/1068 651/702 1065/1161 15

Example 6 228 cm3 / hour of a low temperature hydrotreated Fischer-Tropsch wax (Table VU) was processed over 300 cm3 of a sulfurized NiW / acidic amorphous SiO2-20 Al2O3 catalyst in reactor 1 (Rx1) and the combined effluent was processed over cm 3 of a Pt / SAPO-11 catalyst in reactor 2 (Rx 2). The Pt / SAPO-11 was bound 1026460-42 with 15% by weight alumina. The Pt / SAPO-11 catalyst is a complete hydroisomerization dewaxing catalyst. The product was distilled to obtain a diesel blending material fraction. The yields, operating conditions and product properties are shown in Table VUL 5

Table Vin

Properties of diesel and jet engine mixing materials at different pressures Example ΓΪ5 ΓΪ5 ΠΓ ΓΪ5 ΓΪ6

Pressure, psig 1002 1002 297 297 298

Temperatures Rx 1 / Rx 2, “F 675/600 675/600 666/600 666/600 600/685 LHSVRx 1 / Rx2 1.3 / 4.0 1.3 / 4.0 1.3 / 4.0 1 , 3 / 4.0 0.76 / 2.3

Return gas flow rate, SCFB 5159 5159 4669 4669 4946

Conversion per pass, LV% 77.8 77.8 77.9 77.9 -

Return fractionation point, ° F 702 702 696 696 - H2 consumption, SCFB 461 46Ï 429 429 26Ö

Cooking range of product, ° F 300-700 300-555 300-700 300-555 300-700 API specific weight 55.7 55.2 49.5

Viscosity @ 40 ° C, cSt 2,055 2,237 2,817

Cloud point, ° C 2 2 -37 N, ppm "« Ü "<ÖÜ" Ö4 "<Ü S, ppm <1 <1 <1 <1 <1 SFC analysis

Aromatics, mass% 1.2 0.9 1.4

Alkenes, mass% 5.4 4.8 2.6

Oxygenation products, mass% 0.2 <0.1 <0.1

Saturated compounds, mass% 93.2 94.3 96.0 JFTOT test @ 260 ° C compliant JFTOT test @ 300 ° C compliant

D6468 stability @ 150 ° C

90 minutes 99.3; 99.6 99.8; 99.7 180 minutes 99.8; 99.8 99.8; 99.8

Peroxide formation, ppm

WeekO ï <ï <

Week 1 <ï ï <ï <ï

Week 2 <10 1 4 10 10 4 46 0 43

Week3 [<ï Π Γ <ΐ Rï

Week 4

Acid number, mg KOH / g 0.06 0.05 0.05

D2887 distillation per% by weight, ° F

0.5 / 5 287/304 285/302 293/309 289/305 285/326 10/20 343/384 310/346 344/385 321/348 357/422 1Ö / 4Ö '420/455 382/392 421 / 465 385/397 476/525 1 488 122 566 ~ 424 5 «" 6Ö / 7Ö 523/565 451/463 548/586 455/467 593/623 "80/90 603/652 491/521 625/663 492/522 652/679 95 / 99.5: 689/761 525/547 685/729 525/548 692/708

Products prepared at 300 psig contained more than 2% by weight of unsaturated compounds, more than 1% by weight of olefins, had less than 1 ppm of sulfur and yet had excellent stabilities in diesel and jet engine fuel tests and excellent resistance to the formation of peroxide. All products contain more than 90% paraffins. Products from the Pt / SAPO-11 catalyst showed a lower olefin content, probably due to the presence of the more active Pt component.

The following is a series of comparative examples illustrating that untreated Fischer-Tropsch products are unstable with respect to peroxide formation and that the conventional hydroprocessing operation produces a product with an extremely low amount of unsaturated compounds that is stable with respect to the formation of peroxide.

Comparative example 7 - Preparation of a fully hydrogenated diesel mixing material

A highly paraffinic diesel blending material was prepared from three separate low-temperature Fischer-Tropsch feeds.

Table IX - Properties of Fischer-Tropsch power supplies Property Nutrition 1 Nutrition 2 Nutrition 3

% By weight in mixture 27.8 23.1 49.1

Specific weight, ° API 56.8 44.9 40.0 1026460-44

Sulfur, ppm <1 <1

Oxygen, ppm according to Neut. Act. 1.58 0.65

Types of chemical compounds,% by weight according to GC-MS

Paraffins. 38.4 62.6 85.3

Alkenes 49.5 28.2 1.6

Alcohols 11.5 7.3 9.3

Other species 0.5 3.9 3.8

Distillation according to D-2887, ° F per wt.% 0.5 / 5 80/199 73/449 521/626 TÖ / 3Ö 209/298 483/551 666/758 ~ 5Ö 364 625 84Ö ~ 7Ö / 9Ö 417/485 691/791 926/1039 95 / 99.5 518/709 872/1074 1095/1184

The mixing material was continuously prepared by feeding the various feeds downstream to a hydroprocessing reactor. The reactor was filled with a catalyst containing alumina, silica, nickel and tungsten. The catalyst was sulfurized before use. The conversion per run was kept at about 80% below the fractionation point of the recycle of 665-710 ° F by adjusting the temperature of the catalyst.

The product of the hydroprocessing reactor was continuously distilled after separation and recycling of hydrogen that did not react to provide a gaseous by-product, a light naphtha fraction, a diesel blending fraction and an unreacted fraction. The unreacted fraction was recycled to the hydroprocessing reactor. The temperatures of the distillation column were adjusted to maintain the flame and cloud points at their intended values of 8 ° C and -18 ° C, respectively.

The feeds were mixed for several hours of continuous operation at 1.4 LHSV to provide the representative product A in the table X.

1 026460-45

Table X - Properties of mixed distillate fuel blend material sample Sample Π) A B

Specific weight, ° API 52.7 52.5

Nitrogen ppm 0.24 0.25

Sulfur, ppm <1 0.61

Water, ppm according to Karl Fischer, ppm 21.5

Pour point, ° C -23 -23

Cloud point, ° C -18 -18

Flash point, ° C 58 59

Auto-ignition temperature, ° F 475 410

Viscosity at 25 ° C, cSt 2,564 2,304

Viscosity at 40 ° C, cSt 1,981 1,784

Cetane number 74 723

Aromatics according to supercritical liquid <1 0.9 dust chromatography, wt%

Neutralization number 0

Asoxide, wt% <0.001

Carbon residue according to Ramsbottom, 0.02% by weight

Corrosion of a Cu strip IA

_____ q Ö3 GC-MS analysis

Paraffins, wt% 100 81.64 i / n ratio of paraffin 2.1 10.2

Oxygen as oxygenation products <6 1226, ppm

Alkenes,% by weight 1732

Average carbon number 14.4 .33.33

Distillation according to D-2887 per wt.%, D-2887 D-86 D-2887 D-86

° F and D-86 per vol.%, ° F

Ö5 / 5 255/300 329/356 256/298 334/360 1026460- 46 IQ / 2Ö 1326/368 1366/393 1329/367 1366 / - 30/40 406/449 419/449 400/429 413 / - 50 " 487 "480" 463 "466 6Ö / 7Ö 523/562 510/539 500/537 - / 519 8Ö / 9Ö 600/637 567/597 574/605 - / 572 95 / 99.5 659/705 615/630 626 / 663 587 / 6Ö4

Oxygen may be present in the sample in the form of organic oxygenation products, measured by gas chromatography-mass spectrometry (GC-MS), dissolved or suspended water, measured by Karl Fischer, or dissolved O 2 from the air.

The oxygenation products content was determined by GC-MS. Oxygenation products in the sample were treated with tetraethoxysilane (TEOS) to increase the sensitivity of the technique. No oxygenation products could be detected in Sample A. It has been determined that the detection limit of the art is 6.5 ppm per oxygenation product. With the molecular weight range of diesel fuel, this corresponds to 0.6 ppm of oxygen as oxygenation products. Given that there are roughly 10 oxygenation compounds in a conventional sample just below this detection limit, the maximum amount of oxygen as oxygenation products in the sample is 6 ppm (0.0006 wt%).

Using data from the solubility of O2 in pure compound

It has been determined that the solubility of O2 from the air in product A is approximately 92 ppm (0.0092% by weight). There are no generally available methods for measuring dissolved O2. The GC-MS analyzes are shown in Table XL

Table XI - GC-MS analysis of distillate fuel blending material Formula N-alkane - Branched alkane - Total alkanes in area% area% carbon number C9H20 "2 ^ 96 W ~ 2j96 C10H22 3 ^ 9 1/24 p3 ÜÏ8 C11H24 3 £ Ö "4 ^ 65 M5 2222 C12H26 1/77 M2 Ü3I C13H28 ~ 5i34 1/75 ζ57 1026460-47 ~ CI4fcü [TÖÖ [Ü34 Γβΐ34 Γϊ / 78 C15H32 ~ 2 ~ 6Ii56 847" 243 "05 ^ 4" 243 1 ^ 5 1048 1/7

CnHje Ü99 "544 ^ 742 ~ 2 $ 9

C18 H38 III "64 * 7f2" 4 ^ 4 C19H40 → 3 ^ 98 7 ^ 58 343 C20H42 → 48.145 133 I32 C21H44 Ö38 332 Tm 634 C22H46 Ö22 ~ 2fiÖ "243 844

Percentage of paraffins 100.00

Percentage olefins 0.00

Average carbon number 15.12

Boiling point of average carbon number, ° F 521

Total i / n ratio of the paraffin in the sample 2.08

As stated above, no oxygenation products were detected in product A. Also, product A contains less than 1% by weight of aromatics. The absence of aromatics further increases the likelihood that product A will oxidize rapidly.

Comparative example 8

Preparation of an Alkenic Diesel Fuel Mixing Material In this example, feed 1 of the Fischer-Tropsch product in Table XI was bypassed around the hydroprocessing unit and fed directly to the distillation column. The same catalysts and conditions used in Example 7, including an LHSV of 1.4, were used and the conditions of the distillation column were adjusted to maintain flame and cloud points in the product as were used in Example 7. The yield of diesel fuel blending material was less, in the neighborhood of 73%, due to the requirement of lowering the end point of the diesel fuel blending material to maintain the cloud point.

The diesel fuel blending material was mixed for several hours of continuous operation to provide the representative product B in Table X. In contrast to the operation where all Fischer-Tropsch streams were supplied to the hydroprocessing unit, the diversion of the light components resulted in lower yields of diesel fuel mixing material due to the lower end point of the diesel. The lower endpoint of the diesel was probably due to the higher concentration of heavy n-paraffins in product B. The GC-MS analysis of product B is shown in Table ΧΠ.

Table ΧΠ - GC-MS analysis of product B

Carbon number 1-olefins n-alkanes isoalkanes alcohols Sum i / n ratio of paraffin ~ Ce WW "ÖjÖ3 ÖÖ3 ~ C, ÖfiÖ -QfiÖ ÖjÖÖ 0 ^ 21 Öi21" Q öfiÖ Ö3Ö ~ m "Ö32 Ö32 ~ Ö, 2 ^ 49" 239 1 ^ 3 Ö3Ï 732 Ö36 335 "432 1,202M9 M4" CI 33I 1 ^ 91 "ξ97" Ö33 12.82 "Ü7" C ^ 335 "436" 432 "Ö39 12.52" 38 ~ C ^ 3 235 "436 "439" Ó3Ö Ï39 ÜÖ8 "c £ Ü68" 439 "432" ÓiÖÖ 10.39 0.86 "0 ^" Ö3Ö "436" 633 ~ ÖjÖÖ 10.39 138

~ C ^ 6 Ö3Ö "436" 432 "Ö3Ö 838 W

"c £ Ö3Ö 436 135 030 7/71 Ö37" Ö3Ö 132 Ï38 "ÖiÖÖ ~ 4fi9" Ö36 Ö; Ö3Ö 134 Ï3Ï "Ö3Ö 135" Ö35

Sum 1732 4032 41.14 132 100.00 10

Percentage of paraffins 81.46

Percentage of olefins 17.52

Average carbon number 13.20

Oxygen as oxygenation products, ppm 1226

Total i / n ratio of the paraffin in the sample 1.02 1 026460-49

These results also show that if a portion of the Fischer-Tropsch product is bypassed along the hydroprocessing reactor and mixed in the final mixing material, significant amounts of olefins are included in the mixing material product. The amount of olefins in the mixed material product is in fact ten times as large as the amount of alcohols. The olefins and oxygenation products represent potential stability problems.

Example 9 Stability measurements 10

Product B was tested for 180 minutes at 150 ° C according to ASTM D6468 and was found to have a stability of 99.3%, indicating that this is extremely stable with regard to the formation of deposits in this test

The products were then tested for the formation of peroxide under accelerated formation according to the methods described in U.S. Pat. Nos. 6162956 and 6180842. The products were tested according to a standard method for measuring the accumulation of peroxides. First a 4 oz sample was placed in a brown bottle and aerated for 3 minutes. An aliquot of the sample was then tested for peroxides according to ASTM D3703. The peroxide content of the samples was measured by methods according to ASTM D3703, with the exception that the Freon solvent was replaced by iso-octane. The sample was then sealed and placed in a 60 ° C oven for 1 week. After this time, the peroxide number was repeated and the sample was returned to the oven. The process continued every week until 4 weeks had elapsed and the final peroxide number was obtained. Table ΧΠΙ contains the tendency to form peroxide.

1 026460-50

Table ΧΠΙ - Tendency to form peroxide [A [1

Initially peroxide number 1.3 8, 2

Peroxide number after 1 week at 60 ° C 1.0 35

Peroxide number after 2 weeks at 60 ° C 1.5 156

Peroxide number after 3 weeks at 60 ° C 1.88 204

Peroxide number after 4 weeks at 60 ° C <5> 5

An additional test of product A was performed at 70 ° C. The initial peroxide number and the peroxide number after 4 weeks are both lower than 1 ppm. These results indicate that product A has significantly better peroxide stability than product B. These test results demonstrate the stability of fully hydrogenated Fischer-Tropsch products at low temperature and the tendency to form very quickly peroxide from distillate fuel blending materials containing Fischer. Contain Tropsch streams that have not been hydroprocessed.

10

Example 10

Effect of trace amounts of olefins on peroxide stability

A further study was conducted to determine the effects of adding small amounts of olefinic condensate to the stable mixed material product A from Table X. A 300-600 ° F portion of the cold condensate at low temperature, feed 1 from Table IX was obtained by distillation. The properties of the 300-600 ° F part of the cold condensate are as follows:

Table XIV - Properties of the 300-600 ° F part of the cold condensate Property Value API Specific weight 65.3

Nitrogen, ppm 0.79

Sulfur, ppm 2.29

Bromine number 48.2 1 02 64 60 - 51

Simulated distillation, D-2887 ° F per wt.% 0.5 / 5% 296/302 10/30% 332/383 10% 393 70/90% 459/523 95 / 99.5% 551/654

A GC-MS analysis of the 300-600 ° F portion of the cold condensate gave these results in weight%:

Table XV - GC-MS analysis of the 300-600 ° F part of the cold condensate Carbon number n-olefins Alkans Alcohols Sum ~ C6 ÖÖÖ "ÖÖÖ öiöö öjöö 0 ÖjÖÖ ÖÖO Π54 Ü4" ow ÖÖÖ "032" 032 "o 13Ö 33Ö ~2 ~ 6 £ 2 12 ^ 7 5β5 Π03 88/75 MM6 5 ^ 28 "33.54" C ^ Ï037 1 ^ 4 "034 16.85 C13 M3: 5J2 039 14.44 C3 5 ^ 5" 4 ^ 9 0.19 ”10.74 C5" pi 13ï "ξδδ 132 cS '13o 1/76" Ö3Ö "336 ~ C3" 533 "035" Ö3Ö "Ï39" Ö34 "Ö35" o3Ö “Ö89" 035 Ö33 "Ööö" Ö48 3¾ "ö3ö" δ3ϊ ^ öö ~ öaê

Sum 56.87 37.10 6.03 100.00 5 1 026460-52

Percentage of paraffins 37.10 Oxygen as oxygenation products, 6769 ppm

Percentage olefins 56.87 Oxygen as primary C 12 -C 24 alcohols, ppm

Average carbon number 12.03 Oxygen as primary C7 -C12 alcohols, ppm

Standard deviation 2.10

Percentage of C12-C24 material 55.02

Example 11

The 300-600 ° F portion of the cold condensate was mixed in various amounts with the stable fuel blend material A of Table X and the blends were evaluated for the formation of peroxide with the following results:

Table XVI - Peroxide formation of mixtures 1-5

Sample volume Cold volume stable Alkenes in the Peroxide result versus weeks of condensate number, ml of mixing material, ml of mixture, wt. store at 60 ° C, ppm. ö p Π Π Γ4 1 o ïöö ö <i <i <ï <ï <ï 1 Ö2 9 ^ 8 <ü <ï <ï <ï ü ÜT ~ 1 Ö5 993 Ö3 <ï <i 6.7 "4 ï 99fi Ö6 ü 2i5 7/7 2ÖiÖ ”37.0 1 2 9fi U3 IJ-liiö-

These results show that the mixing material prepared by hydrotreating the entire portion, without direct mixing of cold condensate, is stable with respect to the formation of peroxide. Mixing materials can only tolerate up to 0.2% by weight of cold condensate (0.012% by weight of oxygenating products as alcohols, determined by GC-MS, and about 0.1% by weight of olefins) and still be considered stable. Mixing materials with more than 0.012% by weight of oxygenation products or 0.1% by weight of olefins showed no satisfactory stability. As the oxygenation products content was increased to more than 0.012% by weight, the peroxide stability of the mixing material decreased rapidly.

1 026460-53

Although the invention has been described in detail and with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope thereof.

1 026460-

Claims (41)

A distillate fuel comprising a Fischer-Tropsch distillate fuel blending material, wherein the Fischer-Tropsch distillate fuel blending material comprises: a) unsaturated compounds in an amount between 2 and 20% by weight; b) paraffins in an amount of 80% by weight or more; c) sulfur in an amount less than 1 ppm; d) a cetane index higher than 60; and e) peroxide precursors in an amount such that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C. The distillate fuel according to claim 1, wherein the peroxide precursors are present in an amount such that less than 4 ppm peroxides are formed after four weeks of storage at 60 ° C. 15 The distillate fuel according to claim 1, wherein the peroxide precursors are present in an amount such that less than 1 ppm peroxides are formed after four weeks of storage at 60 ° C. The distillate fuel of claim 1, wherein about 100% by weight of the distillate fuel is a Fischer-Tropsch distillate fuel blending material. The distillate fuel of claim 1, further comprising a petroleum blending material. 25 The distillate fuel of claim 5, wherein the fuel comprises 5 to 75% by weight of Fischer-Tropsch distillate fuel blending material and 95 to 25% by weight of petroleum blending material The distillate fuel of claim 1, wherein the distillate fuel further comprises nitrogen in an amount of less than 1 ppm. 1026460- The distillate fuel according to claim 1, wherein the unsaturated compounds are present in an amount between 2 and 15% by weight. The distillate fuel according to claim 1, wherein the unsaturated compounds 5 are present in an amount between 5 and 10% by weight. The distillate fuel of claim 1, wherein the distillate fuel satisfies at least one specification for either diesel fuel or jet engine fuel. The distillate fuel of claim 10, wherein the distillate fuel meets at least one specification for a diesel fuel and has a cetane index greater than 60. 12. The distillate fuel according to claim 11, wherein the distillate fuel has a cetane index higher than 65. A distillate fuel according to claim 11, wherein the fuel has a percent reflection according to ASTM D6468 greater than 65% when measured at 150 ° C for 90 minutes. 20 A distillate fuel according to claim 11, wherein the fuel has a percent reflection according to ASTM D6468 greater than 65% when measured at 150 ° C for 180 minutes. Fischer-Tropsch mixing material according to claim 19 as a diesel fuel. The distillate fuel according to claim 11, wherein the fuel has a percent reflection according to ASTM D6468 greater than 99% when measured at 150 ° C for 90 minutes. 16. The distillate fuel according to claim 10, wherein the distillate fuel meets at least one specification for a jet engine fuel and has a success assessment in ASTM D3241 at 260 ° C for 2.5 hours. A distillate fuel according to claim 16, wherein the fuel has a pass assessment in ASTM D3241 at 270 ° C for 2.5 hours. A distillate fuel according to claim 16, wherein the fuel has a pass assessment in ASTM D3241 at 300 ° C for 2.5 hours A Fischer-Tropsch diesel fuel blending material comprising: a) unsaturated compounds in an amount between 2 and 10% by weight, the unsaturated compounds comprising less than 10% by weight of polycyclic aromatics; B) paraffins in an amount of 90% by weight or more; c) sulfur in an amount less than 1 ppm; and d) peroxide precursors in an amount such that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C, the fuel having a cetane index higher than 60; and has a percent reflection according to ASTM D6468 at 150 ° C greater than 99% when measured after 180 minutes. The mixing material of claim 19, wherein the mixing material has a cetane index higher than 65 The mixing material of claim 19, wherein the mixing material has a cetane index higher than 70. 22. A Fischer-Tropsch straahnotor fuel mixing material comprising: a) unsaturated compounds in an amount between 2 and 10% by weight, wherein the unsaturated compounds comprise less than 10% by weight of polycyclic aromatics; b) paraffins in an amount of 90% by weight or more; c) sulfur in an amount less than 1 ppm; d) peroxide precursors in an amount such that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C, e) a smoking point of 30 mm or higher, and f) a success assessment in ASTM D3241 at 260 ° C for 2.5 hours. 1 026460- The mixing material of claim 22, wherein the mixing material has a success assessment in ASTM D3241 at 270 ° C for 2.5 hours. 24. Mixing material according to claim 22, wherein the mixing material has a pass assessment in ASTM D3241 at 300 ° C for 2.5 hours 25. A process for the preparation of a highly paraphimic, moderately unsaturated distillate fuel blending material comprising the steps of: a) converting syngas into a Fischer-Tropsch-fed feed through a Fischer-Tropsch process; b) hydroprocessing the feed obtained via Fischer-Tropsch at a temperature of 525-775 ° F, a pressure lower than 1000 psig and a liquid space velocity per hour higher than 0.25 hours1; and c) recovering a highly paraffinic, moderately unsaturated distillate fuel blending material, the highly paraffinic, moderately unsaturated distillate fuel blending material having between 2 and 20 percent by weight of unsaturated compounds, less than 1 ppm sulfur and peroxide precursors in such an amount that less than 5 ppm peroxides are formed after four weeks of storage at 60 ° C. The method of claim 25, wherein the temperature is 575-725 ° F, the pressure is between 200-500 psig and the fluid space velocity per hour is 0.5-1.5 hours * 1. The method of claim 25, wherein the hydroprocessing reprocesses the feed obtained through Fischer-25 Tropsch by performing an operation selected from the group consisting of reducing the content of sulfur, nitrogen and oxygen in the feed; reducing the content of olefins in the diet; increasing the ratio of iso / normal paraffins in the product to between 0.3 and 10; increasing the production of distillate fuel product by converting heavy species into the feed; and combinations thereof. The method of claim 25, wherein the hydroprocessing produces hydrogen and the produced hydrogen is recovered. 1026460- 29. A method according to claim 26, wherein the hydroprocessing produces hydrogen and the produced hydrogen is used in a process selected from the group consisting of hydrotreating, the reduction of CO2, the production of fuel and combinations thereof. The method of claim 25, wherein the hydroprocessing takes place in the presence of a hydroprocessing catalyst using an acidic carrier. 10 The method of claim 25, further comprising removing at least a portion of the polycyclic aromatics from the highly paraffinic, moderately unsaturated distillate fuel blending material. The method of claim 25, further comprising mixing the feed obtained through Fischer-Tropsch with a petroleum blending material to provide a mixed stream and hydroprocessing the mixed stream A distillate fuel comprising a Fischer-Tropsch distillate fuel blending material, wherein the Fischer-Tropsch distillate fuel blending material is prepared according to a process comprising: a) converting syngas into a feed obtained through Fischer-Tropsch by means of a Fischer-Tropsch process; b) hydroprocessing the feed obtained via Fischer-Tropsch at a temperature of 525-775 ° F, a pressure lower than 1000 psig and a liquid space velocity per hour higher than 0.25 hours 1; and c) recovering a Fischer-Tropsch distillate fuel blend material, wherein the Fischer-Tropsch distillate fuel blend material comprises between 2 and 20 weight percent unsaturated compounds, less than 1 ppm sulfur and peroxide precursors in such an amount that less then 5 ppm peroxides are formed after four weeks of storage at 60 ° C. 1026460- The distillate fuel of claim 33, wherein the fuel meets at least one specification for either diesel fuel or jet engine fuel. 35. The distillate fuel of claim 34, wherein the fuel meets at least one specification for a diesel fuel and has a cetane index greater than 60. The distillate fuel of claim 34, wherein the fuel meets at least one specification for a diesel fuel and has a cetane index greater than 65 The distillate fuel of claim 34, wherein the fuel meets at least one specification for a jet engine fuel and has a pass assessment in ASTM D3241 at 260 ° C for 2.5 hours. 38. Method for operating a diesel engine, applying it The method of operating a diesel engine according to claim 38, wherein the diesel tire dust further comprises a petroleum blending material. A method of operating a jet engine, comprising using the Fischer-Tropsch mixing material according to claim 22 as a jet engine fuel A jet engine operating method according to claim 40, wherein the jet engine tire dust further comprises a petroleum blending material