Production of high performance (mesophase) carbon fiber feedstock.

Abstract

A process is provided for the production of mesophase material capable of producing high performance carbon fibers. The mesophase is produced after processing heavy hydrocarbons to remove impurities by hydrotreating or quinoline solvent, followed by removal of light hydrocarbons using toluene solvent, and then upgrading by a soak visbreaking process to produce a desired amount of mesophase material while preventing coke formation.

Description

[Technical Field]

[0001] (Statement of priority) This application claims priority to U.S. Provisional Patent Application No. 63 / 435,987, filed December 29, 2022, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] The production of carbon fiber from low-cost pitch is known to result in carbon fiber with poor mechanical properties compared to carbon fiber prepared from polyacrylonitrile materials. Carbon fiber is a desirable material with excellent thermal and electrical conductivity. Due to the low cost of the feedstock compared to PAN, there are significant cost savings in the use of carbon fiber made from pitch, due to the high availability of feed from sources such as FCC slurry oil, solvent deasphalted pitch, vacuum tower bottoms, steam cracker heavy pyrolysis oil (tar), and other types of residues.

[0003] The term "pitch" refers to a broad range of products, including both naturally occurring heavy materials and those formed by the thermal polymerization of lighter materials. There are two common grades of carbon fiber produced from pitch. These include the use of isotropic pitch to produce lower-quality, general-purpose carbon fibers. These fibers have low strength and stiffness and moderate thermal and electrical conductivity. These carbon fibers are typically useful for concrete reinforcement, thermal insulation, and water treatment. Another type of carbon fiber made from pitch is from the mesophase derived from pitch, producing high-performance carbon fibers. These carbon fibers have excellent thermal and electrical conductivity along with moderate strength and stiffness. The fibers can be used in energy storage applications such as batteries, fuel cells, and supercapacitor electrodes, as well as in rollers in the film and paper industries and in aircraft brake discs. These fibers can be up to three times more expensive than general-purpose carbon fibers. Obstacles facing the widespread adoption of pitch-based carbon fibers include the high cost of carbon fiber compared to glass fiber and steel. Additionally, pitch-based fibers are very brittle compared to other PAN-based fibers. Potential markets for carbon fibers that can be produced at low cost and have excellent properties include use in the automotive industry and in batteries for electric vehicles.

[0004] Hydrocarbon mesophase feedstocks are difficult to use for preparing carbon fibers due to numerous problems, including breakage during spinning to create fibers and high fiber brittleness. This is due to the lack of optimal, low-cost feedstocks for generating clean mesophase feed for carbon fiber production plants. The present invention creates an optimal feedstock for producing high-performance carbon fibers, thereby improving the mechanical properties of carbon fibers and enabling their widespread adoption for use in composites, such as in the automotive industry, as a replacement for steel components. The reduced weight of carbon fiber composites compared to steel offers significant advantages for their use in vehicles, including electric vehicles. More economical, high-quality precursor materials are also useful in energy storage, specialty asphalt, and reinforced plastics and concrete.

[0005] Current high-quality carbon fibers are prepared from polyacrylonitrile (PAN) precursors. However, the use of PAN fibers for carbon fiber production is expensive, and therefore its use is limited to specialized / high-tech applications such as military aircraft parts. Generating optimal low-cost, high-performance carbon fiber production feedstocks would substantially reduce overall production costs and significantly increase available carbon fiber production, which is desirable for a significant increase in new applications. At the same time, producing high-performance carbon fibers using low-cost hydrocarbon-based feedstocks is an effective means of sequestering carbon and effectively addressing Scope 3 emissions.

[0006] The present disclosure takes the output stream of the described SDA unit and further upgrades it to mesophase to enable high-performance carbon fiber production. The upgrading process essentially involves sending the SDA product stream to a soak-carburetor visbreaking-type process, operating at temperatures above 800°F and with a residence time of greater than two minutes to gradually form the desired amount of mesophase while preventing coke formation. After the desired amount of mesophase is produced, the product stream is fed to a carbon fiber production plant to produce the desired high-performance carbon fiber. Without this final thermal upgrading process described herein, it would only be possible to make general performance carbon fiber (GPCF). Note that this thermal upgrading process can consist of staged heating steps to maximize temperature control. Additionally, there can be one or more separation steps downstream of the thermal upgrading process. Summary of the Invention

[0007] A process for producing a hydrocarbon feed for conversion to carbon fiber is provided, the process comprising: passing an untreated, non-hydrotreated feed to a solvent to remove solid contaminants and coke that are not soluble in the solvent, where the hydrocarbons in the untreated, non-hydrotreated feed are soluble in the solvent; then passing the hydrocarbon-containing solvent through a second solvent to remove lighter components; and producing a stream containing heavier hydrocarbon components that is passed to a thermal treatment step to increase the molecular weight of the heavier hydrocarbon components and produce pitch that can be converted to carbon fiber. The thermal treatment step is a soaker visbreaker process operating at above 800°F for more than two minutes, which results in an increase in the amount of desirable mesophase material without producing coke. The mesophase material can then be converted to carbon fiber.

[0008] In another embodiment of the invention, the feed may be hydrotreated to remove contaminants and then sent to a second solvent to remove lighter components prior to the soak visbreaking step. [Brief explanation of the drawings]

[0009] [Figure 1] 1 shows a simplified flow scheme for producing mesophase material used as a raw material for carbon fibers. [Figure 2] 1 shows an alternative flow scheme for producing mesophase material used as a raw material for carbon fiber. DETAILED DESCRIPTION OF THE INVENTION

[0010] The production of carbon fiber from petroleum residual streams for applications such as aircraft brakes, supercapacitors, automotive steel replacement, and other applications has lower production costs due to low feedstock costs and the high availability of feed components from refinery streams. However, due to other components in this type of petroleum residual stream, carbon fibers produced from petroleum residual streams often exhibit poor mechanical properties compared to polyacrylonitrile (PAN)-based carbon fibers, thereby limiting their market adoption. These other components include natural components in the oil, such as volatile gases, sulfur, nitrogen, and organometallic compounds, as well as any residual inorganic materials added during processing (FCC catalysts, particulates contained in crude oil, etc.). This application provides a method for taking readily available petroleum-based streams and processing them into a feedstock that enables direct carbon fiber production and / or carbon fiber production with improved mechanical properties after additional processing.

[0011] Mesophase pitch is an important and relatively recently recognized member of the pitch family that has optical properties and can be used to make carbon fibers, carbon foams, and other exotic valuable materials.

[0012] When natural or synthetic pitches containing aromatic bases are heated under quiescent conditions at temperatures between 350 and 500 °C, small insoluble liquid spheres begin to appear in the pitch and gradually increase in size as heating continues. Examination by electron diffraction and polarized light techniques shows that these spheres consist of layers of oriented molecules aligned in the same direction. As these spheres continue to grow in size with continued heating, they come into contact with one another and gradually coalesce with one another, producing large clumps of aligned layers. As coalescence continues, regions of aligned molecules much larger than those of the original spheres are formed. These regions combine to form a bulk mesophase, and the transition from one oriented region to another occurs smoothly and continuously, sometimes via gradually curving lamellae and sometimes via more sharply curving lamellae. The differences in orientation between the regions create a complex array of polarized light extinction contours in the bulk mesophase, corresponding to various types of linear discontinuities in molecular alignment. The final size of the oriented regions formed depends on the viscosity of the formed mesophase and the rate of viscosity increase, which in turn depends on the specific pitch and heating rate. At certain pitches, domains with sizes exceeding 200 microns and up to 1000 microns are produced, while at other pitches the viscosity of the mesophase is such that only limited coalescence and structural rearrangement of the layers occurs, so that the final domain size does not exceed 100 microns.

[0013] The highly oriented, optically anisotropic, insoluble material produced by processing pitch in this manner has been given the term "mesophase," and pitches containing such materials are known as "mesophase pitches." When such pitches are heated above their softening point, they become a mixture of two essentially immiscible liquids: one optically anisotropic, oriented mesophase portion and the other isotropic, non-mesophase portion. The term "mesophase" comes from the Greek "meso" or "intermediate" and refers to the pseudocrystalline nature of this highly oriented, optically anisotropic material. Mesophases are essentially "liquid crystals," as evidenced by their X-ray diffraction patterns, due to their ordered, repeating arrangement of atoms and their ability to flow when stress is applied. This seemingly contradictory behavior is due to the relatively weak bonding of carbon atoms in adjacent parallel planes.

[0014] In a sense, mesophase pitch is merely a stop on the thermal condensation of hydrocarbons into coke. As time and temperature increase, the aromatic liquid hydrocarbons undergo thermal polymerization, accompanied by some thermal dealkylation. When thermally treating atmospheric or vacuum residues of aromatic crude oil, the first stop is visbroken crude oil, which has a lower viscosity and molecular weight than the feed. The next stops along the thermal processing path are dominated by thermal polymerization, resulting in petroleum pitch. The end of the line is coke. Mesophase pitch is the penultimate stop. While the thermal process is simple to describe, countless processes have been proposed, or at least patented, for making mesophase.

[0015] The term pitch has been used for many heavy products ranging from residual fractions of crude oil to products of thermal polymerization. As used herein, pitch is intended to refer to highly aromatic materials produced by thermal polymerization and having softening points above 100°C.

[0016] Petroleum pitches have been produced by oil refineries for decades. Perhaps the most widely known materials are A-240 pitch and / or M-50, produced by Ashland Petroleum Company and later Marathon Oil Company, respectively. Such pitches with suitable softening points can be satisfactorily used as impregnation materials for electrodes, anodes, and carbon-carbon composites, such as carbon-carbon fiber composites in aircraft brakes and rocket engine nozzles. These pitches can also be used in the nuclear industry to manufacture fuel rods and control rods for graphite-moderated nuclear reactors. Furthermore, such pitches can be used as starting materials for the production of mesophase pitch, which can be used to produce carbon fiber precursors and carbonized fibers, i.e., carbon fiber and graphite fiber. Carbon foams and other pitch-based products can also be made from mesophase pitch.

[0017] The high strength-to-weight ratio of carbon and graphite fibers, alone or in composites, makes such fibers useful in sporting goods, automotive parts, light aircraft, and some aerospace applications. High thermal conductivity and strength make carbon foams useful in thermal management applications, etc. The final carbon fiber, carbon foam, etc., products are high-value specialty products that depend heavily on the properties of the starting mesophase pitch.

[0018] Pitch formation is a thermal process involving heat-induced polymerization. The product has a higher molecular weight than the feed. In contrast, there are other thermal refining processes that use heat to crack or dehydrate the feed. These processes produce products with lower molecular weights than the feed. Thermal cracking processes such as visbreaking, widely licensed by Universal Oil Products, for example, use high temperatures to thermally crack the high molecular weight components of crude oil to produce its own cutter stock and reduce the viscosity of heavy oil products. Steam cracking of naphtha or other light (usually paraffinic) feeds into olefins is an important method for producing ethylene and other light olefins. Steam and naphtha are mixed together and fed through a heater at supersonic velocities at ultra-high temperatures, such as 850°C, and then quenched. Styrene production is catalytic, using large amounts of superheated steam to heat ethylbenzene feed to a temperature where it can be catalytically and endothermically converted to styrene. The state-of-the-art technology for making mesophase pitch can be summarized as follows: There are many processes, most of which involve relatively long batch processes that result in mesophase formation. Some are continuous and use vigorous mechanical agitation after removing a substantial amount of distillate material using a wiped film evaporator, or agitation by injection of inert gas, all of which are difficult to control and involve high temperatures that can cause the mesophase pitch precursor and pitch product to form coke.

[0019] For this discussion, the unconverted oil stream from a hydrocracking unit provides a very good starting point for the production of carbon fiber. Unconverted oil from a hydrocracking unit often contains high concentrations of heavy polynuclear aromatic compounds, which must be removed from the hydrocracking reaction system to prevent catalyst deactivation reactions. In the drawings of U.S. Pat. No. 8,852,404, line 26 is a concentrated stream of these heavy polynuclear aromatics (HPNA). A typical drag stream from a hydrocracking application (see line 25 in U.S. Pat. No. 8,852,404) also contains some polynuclear aromatics before being concentrated.

[0020] Because the net drag stream from the hydrocracking process has already been severely hydrotreated, this HPNA drag stream is typically low in components such as organosulfur, organonitrogen, and organometallic compounds. Furthermore, this stream does not contain catalyst fines that are often found in other refinery heavy streams (FCC clarified slurry oil (CSO) and other pyrolysis residuals) that have been tested for carbon fiber production. However, while this stream may be free of typical heavy contaminants, there are still significant amounts of undesirable lighter materials present that can degrade the quality of the final carbon fiber.

[0021] Therefore, it is proposed to send this HPNA drag stream to a separation process that can remove these lighter materials. Solvent extraction is a process step that can be used to recover the lighter soluble components while eliminating the insoluble components. Solvent extraction steps can include removing heptane-soluble materials such as maltenes, toluene-soluble materials such as asphaltenes, and quinoline-soluble materials such as beta resins, leaving a heavier stream of mesophase hydrocarbons.

[0022] This heavy product stream from the solvent extraction process now represents an excellent feedstock for mesophase production due to the high concentration of heavy polynuclear aromatic compounds and for subsequent carbon fiber production.

[0023] The heavy product stream is maintained at temperatures above 800°F in a soaker visbreaker drum for more than two minutes to gradually form the desired amount of mesophase material, which can then be fed to a carbon fiber production plant. Visbreaking or pyrolysis achieves moderate conversion of the heavy feed to lighter products, including olefinic naphtha. Coking achieves complete conversion of the heavy feed to lighter products, such as coker naphtha, but the olefin and especially diene content of the naphtha is high enough that further processing is required. Large, complex refineries have specialized equipment required for processing the coker naphtha. Typically, either processing at relatively low temperatures over proprietary catalysts to saturate the dienes or blending with conventional naphtha and hydrotreating at pressures two to three times higher than those required for hydrotreating other refinery naphtha fractions is used. Severe hydrotreating of coker naphtha saturates the olefins and significantly reduces the octane, necessitating further processing, such as in a platinum reformer.

[0024] This absence of heavy contaminants and removal of light components makes the recovered material an excellent feed stream for the production of carbon fibers as described in other patents (U.S. Pat. Nos. 9,222,027 and 10,731,084).

[0025] Figure 1 provides one embodiment of the present invention. Petroleum feed 10 is sent to vessel 15 containing quinoline solvent to remove contaminants. Materials not soluble in quinoline are discharged in line 22. Hydrocarbons soluble in quinoline solvent are sent in stream 20 to a second vessel 25 containing toluene solvent, from which toluene-soluble light hydrocarbons are sent in line 30 for use outside the ongoing process, and toluene-insoluble beta resin stream 35 is sent to a soaker visbreaker reactor 40 operating at temperatures exceeding 425°C (800°F), where the material is held for greater than two minutes. The mesophase material 50, an anisotropic pitch, can now be sent for conversion to carbon fiber.

[0026] Figure 2 provides an embodiment of a process in which treatment with quinoline solvent is not required to remove contaminants because this is addressed through the use of a hydrotreating step. In Figure 2, feed 10 is sent to a hydrocracking unit 60, and the effluent is sent to a separation column 70 to separate product 72 and heavier hydrocarbons 74. A portion of the heavier hydrocarbons is recycled in stream 80, and a second portion of the heavier hydrocarbons is sent to a vessel 30 containing toluene solvent to produce mesophase material 50, which is separated into a light hydrocarbon stream 30 and a heavy hydrocarbon stream 35 that is sent to a soaker visbreaker reactor 40 to produce carbon fiber.

[0027] The raw, non-hydrotreated feed (SDA pitch or CSO) is first treated with quinoline to eliminate any solid contaminants or coke present in the feed. This solid-free oil (quinoline solubles) may or may not require hydrotreating before being treated with toluene to remove the lighter components. The heavy components (beta resin or toluene insolubles) are then sent to a thermal treatment step (soaker visbreaker) to grow / polymerize the beta resin or small mesophase into a larger mosaic mesophase (anisotropic pitch). If an isotropic pitch is desired, the thermal step may be omitted.

[0028] If the starting material has already been hydrotreated (hydrocracker UCO), the initial quinoline and hydrotreating steps may not be necessary since the material is already free of contaminants. In this sequence, the feed is treated with toluene and the toluene insolubles are sent to thermal treatment. [Example]

[0029] In this example, clarified slurry oil (CSO) obtained from fluid catalytic cracking of high molecular weight crude oil was processed using two solvent extraction steps in preparation for further thermal processing. In the first extraction step, quinoline was added to the CSO in a 10:1 mass ratio to dissolve the oil. The solution was placed in an oil bath or controlled heating mantle on a hot plate with vigorous stirring. A thermocouple was inserted into the solution to measure the solution temperature, while a second thermocouple measured the temperature of the oil bath. The solution was heated to 80°C under reflux and mixed at this temperature for 2 hours. After 2 hours, the solution was filtered through a Buchner funnel to separate the quinoline insolubles, which were collected on the filter paper, and the quinoline solubles, which were collected in a filter flask. The quinoline solubles were removed by rotary evaporation. The collected quinoline insolubles and solvent-free quinoline solubles were dried in a vacuum oven at 100°C for 12 hours.

[0030] The purpose of this extraction was to remove ash / catalyst and particulate matter from the CSO feed. If not removed, ash / catalyst and particulate matter contaminants would cause defects in the carbon fiber microstructure, resulting in unacceptable brittleness. The dried, solvent-free quinoline soluble material was then subjected to a second extraction. In the second stage extraction, heptane was added to the dried, solvent-free soluble material from the first stage extraction in a 10:1 mass ratio to dissolve the soluble material. The solution was placed in an oil bath or controlled heating mantle on a hot plate with vigorous stirring. A thermocouple was inserted into the solution to measure the solution temperature, while a second thermocouple measured the oil bath temperature. The solution was heated to 80°C under reflux and mixed at that temperature for 2 hours. After 2 hours, the solution was filtered through a Buchner funnel to separate the heptane-insoluble material, which was collected on the filter paper, and the heptane-soluble material, which was collected in a filter flask. The heptane-soluble material was then rotary evaporated to remove the heptane. The collected heptane-insolubles and solvent-free heptane-solubles are dried in a vacuum oven at 100°C for 12 hours. The dried, solvent-free heptane-insolubles are then subjected to thermal treatment. The purpose of this extraction is to remove any volatiles present in the quinoline-solubles and to concentrate the asphaltenes in the HI. If not removed, the volatile components will cause defects in the carbon fiber microstructure, resulting in unacceptable brittleness.

[0031] The dried, solvent-free heptane insolubles are then treated at above 426° C. for more than 2 minutes. The heavy hydrocarbons present in the material form a mesophase after treatment, which now becomes a suitable component for use as feedstock to carbon fiber production facilities.

[0032] Specific Embodiments While the following description will be given in conjunction with specific embodiments, it will be understood that this description is intended to illustrate, not limit, the scope of the preceding description and the appended claims. Without further elaboration, it is believed that, using the preceding description, one skilled in the art can utilize the present disclosure to its fullest extent and easily ascertain the essential characteristics of the present disclosure, and can make various changes and modifications to the present disclosure to adapt it to various uses and conditions, without departing from the spirit and scope of the present disclosure. Therefore, the preceding preferred specific embodiments are to be construed as merely illustrative, and do not limit the remainder of the disclosure in any way, but are intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0033]

[0010] In the above, all temperatures are set forth in degrees Celsius, and all parts and percentages are by weight unless otherwise indicated. A first embodiment of the present disclosure is a process for producing a hydrocarbon feed for conversion to carbon fiber, the process comprising: sending an untreated, non-hydrotreated feed to be mixed with a first solvent to remove contaminants and coke that are not soluble in the solvent, where the hydrocarbons in the untreated, non-hydrotreated feed are soluble in the first solvent; then sending the hydrocarbon-containing first solvent to a second solvent to remove lighter components; producing a stream comprising heavier hydrocarbon components that is sent to a thermal treatment step to increase the molecular weight of the heavier hydrocarbon components to produce pitch; and then converting the pitch to carbon fiber. An embodiment of the present disclosure is one, any, or all of the preceding embodiments to the first embodiment of this paragraph, in which the first solvent is quinoline. An embodiment of the present disclosure is one, any, or all of the preceding embodiments through the first embodiment of this paragraph, wherein the second solvent is toluene. An embodiment of the present disclosure is one, any, or all of the preceding embodiments through the first embodiment of this paragraph, wherein the heat-treating step is greater than 425°C for greater than 2 minutes. An embodiment of the present disclosure is one, any, or all of the preceding embodiments through the first embodiment of this paragraph, wherein the heat-treating step increases the proportion of heavier hydrocarbon components converted to mesophase while reducing the proportion of coke to produce a product stream comprising said mesophase. An embodiment of the present disclosure is one, any, or all of the preceding embodiments through the first embodiment of this paragraph, further comprising sending the product stream to a carbon fiber production plant to produce carbon fibers having a Young's modulus of at least 200 GPa.An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, in which the raw, non-hydrotreated feed comprises thermally produced pyrolysis oil selected from a steam cracker or pyrolysis unit, or a bio-derived oil derived from a plant, animal, waste grease, algae, or microbial source. An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, in which the raw, non-hydrotreated feed is mixed with a solvent to remove solid contaminants, after which the hydrocarbon-containing solvent is sent to a hydrotreating reactor and then to the second solvent extraction. An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, in which the thermal treatment step is a soaker visbreaker step. An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, in which the heavier hydrocarbon components comprise beta resin or toluene-insoluble hydrocarbons. An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, wherein the carbon fiber has a Young's modulus of at least 200 GPa.An embodiment of the present disclosure is one, any, or all of the preceding through first embodiments of this paragraph, wherein the heavier hydrocarbon components are converted to anisotropic pitch.

[0034] A second embodiment of the present disclosure is a process for producing a hydrocarbon feed for conversion to carbon fiber, comprising: passing a hydrotreated stream to a vessel containing toluene to produce a stream comprising toluene and impurities removed from the hydrotreated pitch and a solvent-insoluble stream; and passing the solvent-insoluble stream to a thermal treatment step to produce an anisotropic pitch.

[0035] A third embodiment of the present disclosure is a process for producing a hydrocarbon feed for conversion to carbon fiber, the process comprising: passing an untreated, non-hydrotreated feed to mix with a first solvent to remove contaminants and coke that are not soluble in the solvent, where the hydrocarbons in the untreated, non-hydrotreated feed are soluble in the first solvent; and then passing the hydrocarbon-containing first solvent through a second solvent to remove lighter components and produce a stream comprising heavier hydrocarbon components that are converted to carbon fiber. An embodiment of the present disclosure is one, any, or all of the preceding embodiment of this paragraph through the first embodiment of this paragraph, wherein the carbon fiber has a Young's modulus of at least 50 GPa.

[0036] A fourth embodiment of the present disclosure is a process for producing a hydrocarbon feed for conversion to carbon fiber, the process comprising: passing an untreated, non-hydrotreated feed to mix with a solvent to separate lighter hydrocarbon components from heavier hydrocarbon components; then passing a stream containing the heavier hydrocarbon components to a solvent to remove contaminants and coke to produce a clean heavier hydrocarbon stream that is not soluble in the solvent; and then converting the heavier hydrocarbon stream to carbon fiber.

Claims

1. 1. A process for producing a hydrocarbon feed for conversion to carbon fiber, the process comprising: passing an untreated, non-hydrotreated feed to mix with a first solvent to remove contaminants and coke that are not soluble in the solvent, wherein the hydrocarbons in the untreated, non-hydrotreated feed are soluble in the first solvent; then passing the hydrocarbon-containing first solvent through a second solvent to remove lighter components; producing a stream containing heavier hydrocarbon components that is passed to a thermal treatment step to increase the molecular weight of the heavier hydrocarbon components to produce pitch; and then converting the pitch to carbon fiber.

2. 10. The process of claim 1, wherein the first solvent is quinoline.

3. 10. The process of claim 1, wherein the second solvent is toluene.

4. 10. The process of claim 1, wherein the heat treatment step increases the proportion of the heavier hydrocarbon components that are converted to mesophase while reducing the proportion of coke to produce a product stream comprising the mesophase.

5. 5. The process of claim 4, further comprising sending the product stream to a carbon fiber production plant to produce carbon fibers having a Young's modulus of at least 200 GPa.

6. 10. The process of claim 1, wherein the raw, non-hydrotreated feed comprises thermally produced pyrolysis oil selected from a steam cracker or pyrolysis unit, or a bio-derived oil derived from a plant, animal, waste grease, algae, or microbial source.

7. 10. The process of claim 1, wherein the raw, non-hydrotreated feed is mixed with the solvent to remove solid contaminants, and then the solvent containing the hydrocarbons is sent to a hydrotreating reactor and then to the second solvent extraction.

8. 10. The process of claim 1, wherein the heat treatment step is a soaker visbreaker step.

9. 10. The process of claim 1, wherein the heavier hydrocarbon component comprises beta resin or toluene-insoluble hydrocarbons.

10. 10. The process of claim 1, wherein the heavier hydrocarbon components are converted to anisotropic pitch.

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