Method of converting fischer-tropsch products into aromatics-containing jet fuel

Abstract

Processes for converting Fischer-Tropsch products into aromatics are described. The processes involve processing the Fischer-Tropsch effluent or hydrocracked Fischer-Tropsch effluent (or a selected portion thereof) in a separate, low pressure reforming reaction zone. The reforming catalyst promotes cyclization and aromatics production. The processes can include an isomerization process to convert normal paraffins to isoparaffins.

Description

RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 63 / 693,784, filed on Sep. 12, 2024, the entirety of which is incorporated herein by reference.BACKGROUND

[0002] The Fischer-Tropsch process involves converting synthesis gas comprising carbon monoxide and hydrogen to hydrocarbons using a heterogeneous catalyst.

[0003] Fischer-Tropsch synthesis is known to yield a broad mixture of products including primarily paraffins, and some olefins. The individual compounds of such mixture can contain up to about 200 carbons. Typically, the number of carbons is between about 1 and about 150, with an average number of carbons of about 30. Some Fischer-Tropsch processes yield mixtures enriched with C5-C30 alkanes containing a significant quantity of olefins and oxygenated compounds, such as alcohols or acids. Trace amounts of sulfur-containing or nitrogen-containing products or aromatic compounds can be also present. Such mixtures are known as “light Fischer-Tropsch liquids” or “LFTL.” Both typical Fischer-Tropsch products and LFTL are frequently used as raw material for obtaining various petrochemical products, such as lubrication oil, kerosene, or diesel fuels, among others.

[0004] The ASTM D7566 product specifications for aviation turbine fuel containing synthesized hydrocarbons require 8 to 25 vol % aromatic hydrocarbon compounds in the overall Jet A and A1 fuel composition, while all types of synthetic paraffinic kerosene (SPK), as a blending component made from any permitted path, including Fischer-Tropsch hydroprocessing, typically contain a maximum of 0.5 wt % aromatics. Therefore, aromatics need to be added to the SPK to meet the aromatic requirement for Jet A and A1. Additionally, for production of sustainable aviation fuel (SAF) it would be desirable if the aromatics being added came from a non-fossil fuel source.

[0005] Therefore, there is a need for an improved process for partially converting Fischer-Tropsch liquids and waxes derived from non-fossil CO or CO2 in the syngas into aromatics and / or transportation fuels.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is an illustration of one embodiment of a process for converting a Fischer-Tropsch product into aromatic compounds.

[0007] FIG. 2 is an illustration of another embodiment of a process for converting a Fischer-Tropsch product into aromatic compounds.DESCRIPTION

[0008] The present invention meets this need by providing processes for converting Fischer-Tropsch products into aromatics. The processes involve converting a selected portion of the Fischer-Tropsch effluent or hydrocracked Fischer-Tropsch effluent to aromatic compounds in a separate, low pressure reforming reaction zone. The low-pressure reforming reaction zone typically operates at a pressure of 60 psig to less than 400 psig, while typical hydroprocessing reaction zones (e.g., hydrotreating, hydrocracking, and hydroisomeration) operate at a pressure of 500 psi to 1500 psi. The reforming reaction zone comprises a reforming reactor loaded with a catalyst which promotes cyclization and aromatics production.

[0009] The feed to the reforming reaction zone comprises a portion of the Fischer-Tropsch or Fischer-Tropsch / hydrocracking products boiling around the heavy naphtha and kerosene / light distillate range with a molecular composition of approximately C8-C16 n-paraffins and iso-paraffins which would form alkylated mono or bicyclic compounds boiling in the heavy naphtha-jet range. The temperature, pressure, and catalyst composition are selected to produce the needed level of these cyclic compounds while avoiding excessive deactivation or cracking.

[0010] There are significant economic and environmental incentives to convert Fischer-Tropsch liquids to other products. Fischer-Tropsch liquids and wax can be synthesized from biomass, municipal solid waste, biogas, landfill gas, and carbon dioxide combined with hydrogen from a renewable resource. Synthetic paraffinic kerosene (SPK) is blended with aromatics to meet the specifications for Jet A or Jet A1 which require aromatics content. Because SPK contains minimal aromatics and the specifications for Jet A and Jet A1 require aromatics, making the aromatics from Fischer-Tropsch products relieves the blending level limitations of SPK. Aromatics from Fischer-Tropsch products can also be blended with other renewable products, such as gasoline, naphtha, chemicals, and the like. This provides an advantage over petroleum-based products with respect to carbon intensity and carbon footprint.

[0011] One aspect of the invention comprises a method of converting a Fischer-Tropsch product into aromatic compounds. As discussed above, the Fischer-Tropsch product can contain up to about 200 carbons, with the number of carbons typically being between about 1 and about 150, e.g., C5 to C200, or C5 to C150, or C5 to C125, or C5 to C100, or C5 to C75, or C5 to C50, or C5 to C40, or C5 to C35, or C5 to C30) In one embodiment, the method comprises providing a Fischer-Tropsch product stream comprising normal paraffins above C20 (optionally along with some in the C1 to C19 range), and hydrocracking the Fischer-Tropsch product stream in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins. All or a part of the hydrocracked Fischer-Tropsch product stream is reformed in a reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C15 aromatic compounds.

[0012] In some embodiments, reforming the hydrocracked Fischer-Tropsch product stream comprises reforming at least a portion of the hydrocracked Fischer-Tropsch product stream. In some embodiments, the portion of the hydrocracked Fischer-Tropsch product stream comprises C6 to C16 paraffins. In some embodiments, the portion of the hydrocracked Fischer-Tropsch product stream comprises C7 to C12 paraffins.

[0013] In some embodiments. providing the Fischer-Tropsch product stream comprises reacting synthesis gas comprising hydrogen, and carbon monoxide and / or carbon dioxide in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream.

[0014] In some embodiments, the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200 to 750 psig, or both.

[0015] In some embodiments, the Fischer-Tropsch catalyst comprises a supported Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof.

[0016] In some embodiments, the method further comprises separating the hydrocracked Fischer-Tropsch product stream into at least a C6 to C16 paraffin stream comprising C6 to C16 paraffins before reforming the hydrocracked Fischer-Tropsch product stream; and wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C6 to C16 paraffin stream.

[0017] In some embodiments, the method further comprises separating the hydrocracked Fischer-Tropsch product stream into at least a C7 to C12 paraffin stream comprising C7 to C12 paraffins; and wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C7 to C12 paraffin stream.

[0018] In some embodiments, the hydrocracking reaction conditions comprise a temperature in a range of 290° C. to 470° C., or 315° C. to 430° C., or 340° C. to 400° C., or 350° C. to 375° C.; or a pressure in a range of 300 to 1500 psig, or 500 to 1200 psig, 600 to 1000 psig, 700 to 900 psig; or both.

[0019] In some embodiments, the hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof.

[0020] In some embodiments, the reforming reaction conditions comprise a temperature in a range of 400° C. to 600° C., or 400° C. to 550° C., or 450° C. to 600° C., 450° C. to 550° C., or a pressure in a range of 60 psig to less than 400 psig, or both. The pressure may be 60 to 390 psig, or 60 to 380 psig, or 60 to 375 psig, or 60 to 350 psig, or 60 to 325 psig, or 60 to 300 psig, or 60 to 275 psig, or 60 to 250 psig, or 60 to 225 psig, or 60 to 200 psig, or 60 to 175 psig, or 60-150 psig, or 60-100 psig.

[0021] In some embodiments, the reforming catalyst comprises a zeolite based catalyst with greater than 0 up to 1 wt % of a noble metal, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%, or a chlorinated alumina based catalyst with up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%. For example, in some embodiments, the zeolite-based catalyst comprises zeolite L with Pt. Noble metals include, but are not limited to, Pt, Ru, Rh, Pd, Os, Ir, and Au.

[0022] Another aspect of the invention comprises a method of converting a Fischer-Tropsch product into aromatic compounds. In one embodiment, the method comprises providing a Fischer-Tropsch product stream comprising normal paraffins above C5. A first portion of the Fischer-Tropsch product stream comprising C16+ normal paraffins is hydrocracked in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins. A second portion of the Fischer-Tropsch product stream comprising C5 to C16 normal paraffins is reformed in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds.

[0023] In some embodiments, the method further comprises isomerizing the hydrocracked Fischer-Tropsch product stream in an isomerization reaction zone comprising an isomerization reactor in the presence of an isomerization catalyst under isomerization conditions to form an isomerized product stream comprising C4 to C20 normal paraffins and isoparaffins.

[0024] In some embodiments, the method further comprises separating the isomerized product stream into an SPK stream comprising synthetic paraffinic kerosene according to ASTM D5766, a naphtha stream comprising C5 to C8 paraffins, and an unconverted oil stream comprising C21+ paraffins.

[0025] In some embodiments, the method further comprises recycling the unconverted oil stream to the hydrocracking reaction zone. In some embodiments, in the hydrocracking, isomerization, separation and unconverted oil stream recycling loop, the method comprises introducing the first portion of the Fischer-Tropsch product stream between the hydrocracking and isomerization zone.

[0026] In some embodiments, at least a portion of the naphtha stream is reformed in the reforming reaction zone.

[0027] In some embodiments, the isomerization reaction conditions comprise a temperature in a range of 315° C. to 430° C., or a hydrogen partial pressure in a range of 300 psig to 1000 psig, or both.

[0028] In some embodiments, the isomerization catalyst comprises a 10 member-ring molecular-sieve catalyst with a noble metal. Suitable 10 member-ring molecular-sieve catalysts include, but are not limited to, SAPO-11, ZSM-48, ZSM-5, ZSM-11, Beta, ZSM-12 / MTT, ZSM-23 / MTW, or combinations thereof.

[0029] In some embodiments, the wt % of C7 to C20 isoparaffins in the isomerized product stream is greater than a wt % of C7 to C20 normal paraffins in the isomerized product. In some embodiments, the weight ratio of C7 to C20 isoparaffins C7 to C20 normal paraffins is greater than 1:1, or greater than 2:1, or greater than 2.5:1, or greater than 3:1.

[0030] In some embodiments, the second portion comprises C6 to C12 normal paraffins.

[0031] In some embodiments, providing the Fischer-Tropsch product stream comprises reacting synthesis gas comprising hydrogen and carbon monoxide in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream.

[0032] In some embodiments, the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200-750 psig, or both.

[0033] In some embodiments, the Fischer-Tropsch catalyst comprises a supported Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof.

[0034] In some embodiments, the hydrocracking reaction conditions comprise a temperature in a range of 315° C. to 430° C., or a pressure in a range of 300-1000 psig, or both.

[0035] In some embodiments, the hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof.

[0036] In some embodiments, the reforming reaction conditions comprise a temperature in a range of 400° C. to 600° C., or 400° C. to 550° C., or 450° C. to 600° C., 450° C. to 550° C.; or a pressure in a range of 60 psig to less than 400 psig, or both. The pressure may be 60 to 390 psig, or 60 to 380 psig, or 60 to 375 psig, or 60 to 350 psig, or 60 to 325 psig, or 60 to 300 psig, or 60 to 275 psig, or 60 to 250 psig, or 60 to 225 psig, or 60 to 200 psig, or, or 60 to 175 psig, or 60-150 psig, or 60-100 psig.

[0037] In some embodiments, the reforming catalyst comprises a zeolite based catalyst with greater than 0 up to 1 wt % of a noble metal, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%, or a chlorinated alumina based catalyst with greater than 0 up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%. For example, in some embodiments, the zeolite-based catalyst comprises zeolite L with Pt. Noble metals include, but are not limited to, Pt, Ru, Rh, Pd, Os, Ir, and Au.

[0038] FIG. 1 illustrates one process 100 for converting Fischer-Tropsch products into aromatics.

[0039] The synthesis gas 105 comprising hydrogen and carbon monoxide is sent to the Fischer-Tropsch reaction zone 110 comprising a Fischer-Tropsch reactor. The Fischer-Tropsch product stream 115 comprises C20+ normal paraffins.

[0040] The Fischer-Tropsch reaction conditions may comprise a temperature in a range of 150° C. to 300° C., and / or a pressure in a range of 200-750 psig. The Fischer-Tropsch catalyst may comprise a Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof.

[0041] The Fischer-Tropsch product stream 115 is sent to a hydrocracking reaction zone 120 comprising a hydrocracking reactor. The C5 to C20+ normal paraffins are cracked into C1 to C20 isoparaffins and normal paraffins.

[0042] The hydrocracking reaction conditions may comprise a temperature in a range of 315° C. to 430° C., and / or a pressure in a range of 300-1000 psig. The hydrocracking catalyst may comprise Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof.

[0043] The hydrocracked Fischer-Tropsch product stream 125 is sent to a reforming zone 130 comprising a reforming reactor where the C6 to C16 isoparaffins and normal paraffins are converted to C6 to C16 aromatic compounds.

[0044] The reforming reaction conditions may comprise a temperature in a range of 400° C. to 600° C. and / or a pressure in a range of 60 psig to less than 400 psig. The reforming catalyst may comprise a zeolite based catalyst with greater than 0 up to 1 wt % of a noble metal, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%, or a chlorinated alumina based catalyst with up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof, or up to 0.75%, or up to 0.5%, or up to 0.3%, or up to 0.2%, or up to 0.1%.

[0045] The aromatic product stream 135 can be blended with synthetic paraffinic kerosene to form aviation fuel. If the synthetic paraffinic kerosene is also made from Fischer-Tropsch products, it is sustainable aviation fuel.

[0046] FIG. 2 illustrates another process 200 for converting Fischer-Tropsch products into aromatics.

[0047] The synthesis gas 205 is sent to the Fischer-Tropsch reaction zone 210 comprising a Fischer-Tropsch reactor where it is converted to C5+ normal paraffins. The Fischer-Tropsch reaction conditions may be as described above.

[0048] The Fischer-Tropsch product is separated into a first stream 215 comprising C5 to C16 normal paraffins and a second stream 220 comprising C16+ normal paraffins.

[0049] The first stream 215 is sent to a reforming reaction zone 225 comprising a reforming reactor where the C5 to C16 normal paraffins are converted to Co to C16 aromatic compounds. The reforming conditions and catalysts may be as described above.

[0050] The second stream 220 is sent to a hydrocracking reaction zone 235 where the C16+ normal paraffins are cracked into C1 to C20 paraffins. The hydrocracking conditions and catalysts may be as discussed above.

[0051] The hydrocracked stream 240 may be sent to an isomerization reaction zone 245 comprising an isomerization reactor where the C1 to C20 normal paraffins are converted to C4 to C20 normal paraffins and isoparaffins.

[0052] The isomerization reaction conditions comprise a temperature in a range of 315° C. to 430° C., and / or a hydrogen partial pressure in a range of 300 psig to 1000 psig. The isomerization catalyst comprises a molecular sieve of AEL (SAPO-11) or MTT or TON framework type, or of intergrowth structure in the ZSM-48 family, as defined by international zeolite association (IZA), with a noble metal, such as platinum or palladium.

[0053] The isomerized reaction mixture can be separated into a synthetic paraffinic kerosene stream 250 comprising C7 to C20 normal and isoparaffins meeting the ASTM D7566 specification, a naphtha stream 255 comprising C5 to C8 paraffins, and an unconverted oil stream 260 comprising C21+ paraffins.

[0054] The synthetic paraffinic kerosene stream 250 can be blended with the aromatic product stream 230 to form sustainable aviation fuel.

[0055] The naphtha stream 255 can be sent to the reforming reaction zone 225 to form additional aromatic compounds. However, because the naphtha stream is obtained after the isomerization reaction zone, it may contain more isoparaffins than naphtha from the Fischer-Tropsch product, and isoparaffins do not aromatize as easily as normal paraffins. Alternatively, the naphtha stream 255 could be sent to another reforming reaction zone.

[0056] The unconverted oil stream 260 can be recycled to the hydrocracking reaction zone 235.EXAMPLES

[0057] The reforming and recycle data in Examples 1-4 are from computer simulations. Examples 5-6 were actual experiments.Example 1

[0058] From full Fischer-Tropsch liquid, a light F-T oil stream is separated out and recovered to have the composition listed in Table 1 below. The stream is processed in a reforming unit to generate aromatics. The product stream from reforming reactor is further processed in a separation system to remove hydrogen and other light gas, and to recover three separate product streams: a light naphtha reformed stream, a C7 / C8 reformed stream and a heavy aromatic stream. The light naphtha reformed stream is recycled to the reforming unit. At optimal operation conditions, the compositions of product streams are listed in Table 1 below.TABLE 1light F-T oil stream reforming to Aromatics with lightnaphtha product stream recycle. All composition in wt %lightlight naphthaC7 / C8heavyF-T oilreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—0.7C6s2.697.90.8C7s9.11.466.95.0C8s20.00.132.323.3C9s26.929.2C10s25.525.1C11+15.917.4Total n-76.91.77.40.5paraffinTotal iso-4.83.522.90.6paraffinTotal olefin16.20.73.70.1Total cyclo-2.00.12.40.6paraffinTotal0.0194.163.598.2aromaticsExample 2

[0059] The same as Example 1, except that the C7 / C8 reformed stream is recycled instead of the light naphtha reformed stream. The product stream compositions are listed in Table 2.TABLE 2light F-T oil stream reforming to Aromatics with toluene-richreformed product stream recycle. All composition in wt %lightlight naphthaC7 / C8heavyF-T oilreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—3.1C6s2.650.20.8C7s9.145.292.85.0C8s20.01.56.326.2C9s26.928.3C10s25.524.0C11+15.916.6Total n-76.916.73.10.2paraffinTotal iso-4.842.28.40.2paraffinTotal olefin16.23.20.80.0Total cyclo-2.00.50.50.1paraffinTotal0.0137.487.299.4aromaticsExample 3

[0060] The same as Example 1, except that a heavy F-T oil stream is used as feed instead of the light F-T oil stream. The product stream compositions are listed in Table 3.TABLE 3heavy F-T oil stream reforming to Aromatics with light naphthareformed product stream recycle. All composition in wt %heavylight naphthaC7 / C8heavyF-T oilreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—0.7C6s0.495.60.7C7s2.33.438.05.0C8s7.50.361.310.5C9s18.019.6C10s32.328.2C11+39.636.7Total n-80.33.011.10.4paraffinTotal iso-1.96.947.90.5paraffinTotal olefin14.51.16.00.1Total cyclo-3.20.14.60.4paraffinTotal0.0388.930.398.6aromaticsExample 4

[0061] The same as Example 2, except that a heavy F-T oil stream is used as feed instead of the light F-T oil stream. The product stream compositions are listed in Table 3.TABLE 4heavy F-T oil stream reforming to Aromatics with C7 / C8reformed product stream recycle. All composition in wt %heavylight naphthaC7 / C8heavyF-T oilreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—5.0C6s0.468.20.8C7s2.326.389.55.0C8s7.50.49.712.7C9s18.019.7C10s32.327.3C11+39.635.4Total n-80.321.27.90.3paraffinTotal iso-1.957.727.10.6paraffinTotal olefin14.53.92.00.1Total cyclo-3.20.51.20.1paraffinTotal0.0316.761.798.9aromaticsExample 5

[0062] A full Fischer-Tropsch liquid was processed through a hydro-cracking and hydro-isomerization unit. The hydro-processed product was further processed in a separation system to remove hydrogen and other light gas, and to recover two separate product streams: a synthetic-paraffinic-kerosene stream and a unconverted oil stream. The unconverted oil stream was recycled to hydro-cracking while a portion of the SPK stream was processed in a UOP CCR Platforming unit to produce aromatics. The SPK stream had the composition listed in Table 5 below. The reformed product was processed in the same way as described in Example 1. The product stream compositions are listed in Table 5.TABLE 5SPK stream reforming to Aromatics with light naphtha reformedproduct stream recycle. All composition in wt %light naphthaC7 / C8heavySPKreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—0.7C6s0.296.70.8C7s4.42.561.45.0C8s13.00.137.916.0C9s23.224.3C10s28.825.5C11+30.429.3Total n-47.92.88.70.4paraffinTotal iso-51.26.730.60.4paraffinTotal olefin—0.93.70.1Total cyclo-0.80.12.80.3paraffinTotal0.0489.454.298.8aromaticsExample 6

[0063] The same as Example 5, except that the C7 / C8 reformed stream was recycled instead of the light naphtha reformed stream. The product stream compositions are listed in Table 6.TABLE 6SPK stream reforming to Aromatics with C7 / C8 reformedproduct stream recycle. All composition in wt %light naphthaC7 / C8heavySPKreformedreformedaromaticstreamstreamstreamstreamC4 / C5s—4.2C6s0.257.10.8C7s4.437.488.55.0C8s13.01.310.717.8C9s23.224.1C10s28.824.8C11+30.428.3Total n-47.918.24.80.3paraffinTotal iso-51.251.417.00.4paraffinTotal olefin—3.41.30.0Total cyclo-0.80.50.70.1paraffinTotal0.0426.676.299.2aromatics

[0064] It can be seen from the above examples that reforming reaction is effective in generating aromatics with a feed stream from appropriate cuts of a Fischer-Tropsch product stream, a hydrocracked Fischer-Tropsch product stream, or an isomerized product stream. The aromatic-rich product streams also had appropriate molecular weight to serve as kerosene or gasoline blending components to satisfy the corresponding fuel specifications. The examples also demonstrated that configuration change of reforming reaction section could effectively shift the composition of C7 / C8 reformed stream to accommodate specific needs, such as fuel blending or renewable aromatic production. Such shifts are obviously not limited to the demonstrated composition shift on C7 / C8 aromatics, and one skilled in the art could implement alternative configurations to adjust aromatic compositions of a different carbon range.Specific Embodiments

[0065] While the following is described in conjunction with specific embodiments, it will be understood that this description is intended to illustrate and not limit the scope of the preceding description and the appended claims.

[0066] A first embodiment of the invention is a method of converting a Fischer-Tropsch product into aromatic compounds comprising providing a Fischer-Tropsch product stream comprising C20+ normal paraffins; hydrocracking the Fischer-Tropsch product stream in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins; reforming the hydrocracked Fischer-Tropsch product stream in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming at least a portion of the hydrocracked Fischer-Tropsch product stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the portion of the hydrocracked Fischer-Tropsch product stream comprises C6 to C16 paraffins. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the portion of the hydrocracked Fischer-Tropsch product stream comprises C7 to C12 paraffins. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein providing the Fischer-Tropsch product stream comprises reacting synthesis gas comprising hydrogen and carbon monoxide or carbon dioxide or both in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200 to 750 psig, or both; or the Fischer-Tropsch catalyst comprises a Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof; or both. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph further comprising separating the hydrocracked Fischer-Tropsch product stream into at least a C6 to C16 paraffin stream comprising C6 to C16 paraffins before reforming the hydrocracked Fischer-Tropsch product stream; and wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C6 to C16 paraffin stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph further comprising separating the hydrocracked Fischer-Tropsch product stream into at least a C7 to C12 paraffin stream comprising C7 to C12 paraffins; and wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C7 to C12 paraffin stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the hydrocracking reaction conditions comprise a temperature in a range of 290° C. to 470° C., or a pressure in a range of 300 to 1000 psig, or both; or the hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph wherein the reforming reaction conditions comprise a temperature in a range of 400° C. to 600° C., or a pressure in a range of 60 psig to less than 400 psig, or both; or the reforming catalyst comprises a zeolite based catalyst with greater than 0 up to 1 wt % of a noble metal, or a chlorinated alumina based catalyst with greater than 0 up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof; or both.

[0067] A second embodiment of the invention is a method of converting a Fischer-Tropsch product into aromatic compounds comprising providing a Fischer-Tropsch product stream comprising C5+ normal paraffins; hydrocracking a first portion of the Fischer-Tropsch product stream comprising C16+ normal paraffins in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins; reforming a second portion of the Fischer-Tropsch product stream comprising C5 to C16 normal paraffins in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph further comprising isomerizing the hydrocracked Fischer-Tropsch product stream in an isomerization reaction zone comprising an isomerization reactor in the presence of an isomerization catalyst under isomerization conditions to form an isomerized product stream comprising C4 to C20 normal paraffins and isoparaffins. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph further comprising separating the isomerized product stream into an SPK stream comprising synthetic paraffinic kerosene, a naphtha stream comprising C5 to C8 paraffins, and an unconverted oil stream comprising C21+ paraffins. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph further comprising recycling the unconverted oil stream to the hydrocracking reaction zone. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein at least a portion of the naphtha stream is reformed in the reforming reaction zone. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the isomerization reaction conditions comprise a temperature in a range of 315° C. to 430° C., or a hydrogen partial pressure in a range of 300 psig to 1000 psig, or both; or the isomerization catalyst comprises a molecular sieve of AEL or MRE framework with a noble metal; or both. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein a wt % of C7 to C20 isoparaffins in the isomerized product stream is greater than a wt % of C7 to C20 normal paraffins in the isomerized product. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the second portion comprises C6 to C12 normal paraffins. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein providing the Fischer-Tropsch product stream comprises reacting synthesis gas comprising hydrogen and carbon monoxide in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200 to 750 psig, or both; or the Fischer-Tropsch catalyst comprises a Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof; or both. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the hydrocracking reaction conditions comprise a temperature in a range of 290° C. to 470° C., or a pressure in a range of 300 to 1500 psig, or both; or the hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof; or both. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph wherein the reforming reaction conditions comprise a temperature in a range of 400° C. to 600° C., or a pressure in a range of 60 psig to less than 400 psig, or both; or the reforming catalyst comprises a zeolite based catalyst with greater than 0 up to 1 wt % of a noble metal, or a chlorinated alumina based catalyst with greater than 0 up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof; or both.

[0068] A third embodiment of the invention is a method of converting a Fischer-Tropsch product into aromatic compounds comprising providing a Fischer-Tropsch product stream comprising C5+ normal paraffins; isomerizing a first portion of the Fischer-Tropsch product stream in an isomerization reaction zone comprising an isomerization reactor in the presence of an isomerization catalyst under isomerization conditions to form an isomerized product stream comprising C4 to C20 normal paraffins and isoparaffins and C20+ hydocarbons; separating the isomerized product stream into an SPK stream comprising synthetic paraffinic kerosene comprising C9-C16 paraffins, a naphtha stream comprising C5 to C8 paraffins, and an unconverted oil stream comprising C21+ paraffins; hydrocracking the unconverted oil stream in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked oil stream comprising C1 to C20 isoparaffins and normal paraffins; passing the hydrocracked oils stream to the isomerization reaction zone; reforming a second portion of the Fischer-Tropsch product stream comprising C5 to C16 normal paraffins in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds. Without further elaboration, it is believed that using the preceding description that one skilled in the art can utilize the present invention to its fullest extent and easily ascertain the essential characteristics of this invention, without departing from the spirit and scope thereof, to make various changes and modifications of the invention and to adapt it to various usages and conditions. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limiting the remainder of the disclosure in any way whatsoever, and that it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0069] In the foregoing, all temperatures are set forth in degrees Celsius and, all parts and percentages are by weight, unless otherwise indicated.

Claims

1. A method of converting a Fischer-Tropsch product into aromatic compounds comprising:providing a Fischer-Tropsch product stream comprising C20+ normal paraffins;hydrocracking the Fischer-Tropsch product stream in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins; andreforming the hydrocracked Fischer-Tropsch product stream in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds.

2. The method of claim 1 wherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming at least a portion of the hydrocracked Fischer-Tropsch product stream.

3. The method of claim 2 wherein the portion of the hydrocracked Fischer-Tropsch product stream comprises C6 to C16 paraffins.

4. The method of claim 2 wherein the portion of the hydrocracked Fischer-Tropsch product stream comprises C7 to C12 paraffins.

5. The method of claim 1 wherein providing the Fischer-Tropsch product stream comprises:reacting synthesis gas comprising hydrogen and carbon monoxide or carbon dioxide or both in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream; and wherein:the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200 to 750 psig, or both; orthe Fischer-Tropsch catalyst comprises a Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof;or both.

6. The method of claim 1 further comprising:separating the hydrocracked Fischer-Tropsch product stream into at least a C6 to C16 paraffin stream comprising C6 to C16 paraffins before reforming the hydrocracked Fischer-Tropsch product stream; andwherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C6 to C16 paraffin stream.

7. The method of claim 1 further comprising:separating the hydrocracked Fischer-Tropsch product stream into at least a C7 to C12 paraffin stream comprising C7 to C12 paraffins; andwherein reforming the hydrocracked Fischer-Tropsch product stream comprises reforming the C7 to C12 paraffin stream.

8. The method of claim 1 wherein:the hydrocracking reaction conditions comprise a temperature in a range of 290° C. to 470° C., or a pressure in a range of 300 to 1500 psig, or both; orthe hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof;or both.

9. The method of claim 1 wherein:the reforming reaction conditions comprise a temperature in a range of 400° C. to 600° C., or a pressure in a range of 60 psig to less than 400 psig, or both; orthe reforming catalyst comprises a zeolite-based catalyst with greater than 0 up to 1 wt % of a noble metal, or a chlorinated alumina based catalyst with greater than 0 up to 1 wt % of a noble metal, Sn, Ge, Ga, In, Re, or combinations thereof;or both.

10. A method of converting a Fischer-Tropsch product into aromatic compounds comprising:providing a Fischer-Tropsch product stream comprising C5+ normal paraffins,hydrocracking a first portion of the Fischer-Tropsch product stream comprising C16+ normal paraffins in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked Fischer-Tropsch product stream comprising C1 to C20 isoparaffins and normal paraffins; andreforming a second portion of the Fischer-Tropsch product stream comprising C5 to C16 normal paraffins in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds.

11. The method of claim 10 further comprising:isomerizing the hydrocracked Fischer-Tropsch product stream in an isomerization reaction zone comprising an isomerization reactor in the presence of an isomerization catalyst under isomerization conditions to form an isomerized product stream comprising C4 to C20 normal paraffins and isoparaffins.

12. The method of claim 11 further comprising:separating the isomerized product stream into an SPK stream comprising synthetic paraffinic kerosene comprising C9-C16 paraffins, a naphtha stream comprising C5 to C8 paraffins, and an unconverted oil stream comprising C21+ paraffins.

13. The method of claim 12 further comprising:recycling the unconverted oil stream to the hydrocracking reaction zone.

14. The method of claim 12 wherein at least a portion of the naphtha stream is reformed in the reforming reaction zone.

15. The method of claim 11 wherein:the isomerization reaction conditions comprise a temperature in a range of 315° C. to 430° C., or a hydrogen partial pressure in a range of 300 psig to 1000 psig, or both; orthe isomerization catalyst comprises a one-dimensional 10 member-ring molecular-sieve catalyst with a noble metal.

16. The method of claim 11 wherein a wt % of C to C20 isoparaffins in the isomerized product stream is greater than a wt % of C7 to C20 normal paraffins in the isomerized product.

17. The method of claim 10 wherein the second portion comprises C6 to C12 normal paraffins.

18. The method of claim 10 wherein providing the Fischer-Tropsch product stream comprises:reacting synthesis gas comprising hydrogen and carbon monoxide in a Fischer-Tropsch reaction zone comprising a Fischer-Tropsch reactor in the presence of a Fischer-Tropsch catalyst under Fischer-Tropsch reaction conditions to form the Fischer-Tropsch product stream; and wherein:the Fischer-Tropsch reaction conditions comprise a temperature in a range of 150° C. to 300° C., or a pressure in a range of 200 to 750 psig, or both; orthe Fischer-Tropsch catalyst comprises a Fe-, Co-, Ni-, Ru-based catalyst or combinations thereof;or both.

19. The method of claim 10 wherein:the hydrocracking reaction conditions comprise a temperature in a range of 290° C. to 470° C., or a pressure in a range of 300 to 1500 psig, or both; orthe hydrocracking catalyst comprises Y zeolite, beta zeolite, SiO2—Al2O3, noble metals, base metals, or combinations thereof;or both.

20. A method of converting a Fischer-Tropsch product into aromatic compounds comprising:providing a Fischer-Tropsch product stream comprising C5+ normal paraffins;isomerizing a first portion of the Fischer-Tropsch product stream in an isomerization reaction zone comprising an isomerization reactor in the presence of an isomerization catalyst under isomerization conditions to form an isomerized product stream comprising C4 to C20 normal paraffins and isoparaffins and C20+ hydocarbons;separating the isomerized product stream into an SPK stream comprising synthetic paraffinic kerosene comprising C9-C16 paraffins, a naphtha stream comprising C5 to C8 paraffins, and an unconverted oil stream comprising C21+ paraffins;hydrocracking the unconverted oil stream in a hydrocracking reaction zone comprising a hydrocracking reactor in the presence of a hydrocracking catalyst under hydrocracking conditions to form a hydrocracked oil stream comprising C1 to C20 isoparaffins and normal paraffins;passing the hydrocracked oils stream to the isomerization reaction zone;reforming a second portion of the Fischer-Tropsch product stream comprising C5 to C16 normal paraffins in a reforming reaction zone comprising a reforming reactor in the presence of a reforming catalyst under reforming conditions to form an aromatic product stream comprising C6 to C16 aromatic compounds.

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