Use of a blend of waste plastics and bio-based raw materials for circular economy polyethylene production.

Abstract

Provided is a continuous process for converting waste plastics into recycling for polyethylene polymerization. This process includes a step of selecting waste plastics containing polyethylene and / or polypropylene, and a step of preparing a blend of the biofeedstock and the selected plastics. The amount of plastic in the blend constitutes 20 wt% or less of the blend. The blend is passed through an FCC unit. Liquefied petroleum gas LPG olefin / paraffin mixture and naphtha are recovered from the FCC unit and can be used for the production of polyethylene.

Description

Technical Field

[0001] (Cross - reference to Related Applications) This application claims priority to U.S. Provisional Application No. 63 / 359,565, filed on July 8, 2022, the entire disclosure of which is hereby incorporated by reference in its entirety.

Background Art

[0002] As part of efforts to combat global warming, the industry is rapidly increasing its activities to produce chemicals and fuels from renewable resources such as bio - based raw materials.

[0003] On the other hand, the world has witnessed a very rapid growth in plastic production. According to the Plastics Europe Market Research Group, the global plastic production volume was 335 million tons in 2016, 348 million tons in 2017, 359 million tons in 2018, and 367 million tons in 2020. According to McKinsey & Company, if the current trajectory continues, the global plastic waste volume is estimated to reach 460 million tons per year by 2030.

[0004] Single - use plastic waste has become an increasingly important environmental problem. At present, there seem to be few options for recycling polyethylene and polypropylene waste plastics into value - added chemical products or fuel products. Currently, only a small amount of polyethylene and polypropylene are recycled via chemical recycling, and these recycled and purified polymer pellets are pyrolyzed in a pyrolysis unit to produce fuels (naphtha, diesel), feedstock for steam crackers, or slack wax. Most (over 80%) are incinerated, landfilled, or discarded.

[0005] Current methods of chemical recycling via pyrolysis cannot have a significant impact on the plastics industry. Current pyrolysis operations produce low-quality fuel components (products in the naphtha and diesel ranges), but these are produced in sufficiently small quantities to be blended into fuel feed. However, to address environmental concerns and recycle the very large quantities of waste polyethylene and waste polypropylene, such simple blending cannot be sustained. The products directly from the pyrolysis units are of such poor quality that they cannot be blended in large quantities into transport fuel.

[0006] Processes for converting waste plastics into hydrocarbon lubricants are known. For example, U.S. Patent No. 3,845,157 discloses the decomposition of waste polyolefins or unused polyolefins to form gaseous products such as ethylene / olefin copolymers, which are then further processed to produce synthetic hydrocarbon lubricants. U.S. Patent No. 4,642,401 discloses the production of liquid hydrocarbons by heating crushed polyolefin waste at temperatures of 150-500°C and pressures of 20-300 bar. U.S. Patent No. 5,849,964 discloses a process for depolymerizing waste plastic materials into volatile and liquid phases. The volatile phase is separated into a gas phase and a condensate. The liquid phase, condensate, and gas phase are purified into liquid fuel components using standard refining techniques. U.S. Patent No. 6,143,940 discloses a procedure for converting waste plastics into a heavy wax composition. U.S. Patent No. 6,150,577 discloses a process for converting waste plastics into lubricating oil. European Patent Application Publication No. 0620264 discloses a process for producing lubricating oil from waste polyolefins or unused polyolefins, comprising thermally decomposing the waste in a fluidized bed to form a waxy product, optionally using a hydrogenation treatment, and then recovering the lubricating oil by catalytic isomerization and fractional distillation.

[0007] Other documents relating to processes for converting waste plastics into lubricants include U.S. Patents 6,288,296, 6,774,272, 6,822,126, 7,834,226, 8,088,961, 8,404,912, and 8,696,994, as well as U.S. Patent Application Publications 2021 / 0130699, 2019 / 0161683, 2016 / 0362609, and 2016 / 0264885. The aforementioned patent documents are incorporated herein by reference in their entirety.

[0008] Globally, recycling and upcycling plastic waste are attracting significant attention as a way to conserve resources and the environment. Mechanical recycling of plastic waste is considerably limited due to the varying types, properties, additives, and contaminants of the collected plastics. Typically, recycled plastics are of lower quality. Chemical recycling, either into starting materials or value-added chemicals, is emerging as a more desirable approach.

[0009] However, a more robust process is needed to industrially and massively chemically recycle single-use plastics and reduce their environmental impact. This improved process should establish a "circular economy" for waste polyethylene and polypropylene plastics, where used waste plastics are effectively recycled as starting materials for polymers or value-added chemicals or fuels. Establishing such a circular economy and utilizing renewable resources such as bio-based raw materials can further enhance the environmental benefits of such recycling processes. [Overview of the project]

[0010] The provided solution is an integrated process for converting plastic waste into recycled polyethylene polymer. This process involves selecting waste plastics to blend with bio-based raw materials, and then feeding the blend of waste plastics and bio-based raw materials into a conversion unit for conversion. This conversion process produces clean monomers and chemical intermediates for ethylene polymerization. The blend contains approximately 20 wt% or less of the selected waste plastics. In one embodiment, the blend is fed into a purification conversion unit, such as an FCC unit.

[0011] The term "bio" refers to biochemical and / or natural chemical substances that exist in nature. Therefore, bio feedstock or bio oil will contain such natural chemical substances. Preferred starting bio feedstocks for blend preparation include triglycerides and fatty acids, plant-derived oils (such as palm oil, canola oil, corn oil, and soybean oil), and animal-derived fats and oils (such as animal fat, lard, schmalz (e.g., chicken fat), and fish oil), as well as mixtures thereof.

[0012] Integrating this process into oil refinery is a key aspect of this process, enabling a circular economy with single-use waste plastics such as polyethylene. Thus, the blend is passed through a refined FCC unit. The blend is passed through at a temperature above its pour point so that it can be pumped into the refined FCC unit. The blend is heated to a temperature above the melting point of the plastic before being injected into the reactor. From the FCC unit, the liquefied petroleum gas C3 olefin / paraffin mixture is recovered. The C3 olefin / paraffin mixture is passed through a steam cracker to produce ethylene, from which polyethylene and polyethylene products can be prepared.

[0013] In another embodiment, a C4 olefin / paraffin mixture is recovered from the FCC unit, similar to the C3 mixture. These two flows are passed together through a steam cracker to produce ethylene. This mixture may optionally also contain naphtha (C5-C8).

[0014] A refinery generally has its own supply of hydrocarbons flowing through its refinery units. A crucial aspect of this process is that it must not negatively impact the refinery's operations. The refinery must still produce valuable chemicals and fuels. Otherwise, integrating this process into an oil refinery would not be a viable solution. Therefore, the flow rate must be carefully monitored.

[0015] The volume of the flow of waste plastic / bioresource blend into the purification unit can consist of any practical or scalable volume % (vol%) of the total flow (total flow rate) into the purification unit. Generally, the blend flow rate can be up to approximately 100 vol% of the total flow rate (i.e., in this maximum case, the blend flow rate is the total flow rate excluding the purification flow rate). In one embodiment, the blend flow rate is up to approximately 50 vol% of the total flow rate (i.e., the purification flow rate plus the blend flow rate).

[0016] Among other factors, the blend of waste plastics and bio-based materials can be adjusted, and this blend has been found to be stable enough to be stored or transported as needed. Furthermore, this blend can be converted into value-added chemicals or fuels in a conversion unit. The combined use of waste plastics and bio-based materials significantly improves the environmental aspects of the conversion and recycling process. In addition, by incorporating the conversion unit as part of a refinery operation, waste plastics can be recycled efficiently and effectively, while also complementing the refinery operation in the preparation of high-value products such as gasoline, jet fuel, base oils, and diesel. However, it has also been found that by adding a refinery operation, clean LPG (propane, propylene, butane, and butene) and naphtha can be efficiently and effectively produced from waste plastics, ultimately leading to the production of polyethylene polymers. Positive economic benefits are realized throughout the entire process, from recycled plastics to polymer products with product quality equivalent to unused polymers, while the use of blends of bio-based materials and waste plastics enhances the environmental aspects of the recycling process. [Brief explanation of the drawing]

[0017] [Figure 1] This illustrates current practices (basic case) of pyrolysis of waste plastics to produce fuel or wax.

[0018] [Figure 2] This process involves preparing a homogeneous liquid blend of plastic and bio-based materials at high temperatures and supplying that blend to a conversion unit.

[0019] [Figure 3] This document details the process for preparing a stable blend unit and how that stable blend is supplied to the conversion unit.

[0020] [Figure 4]It shows the type classification of plastics regarding the recycling of waste plastics.

[0021] [Figure 5] It shows this process in which the prepared blend is passed through the refinery's conversion FCC unit to produce valuable chemicals and chemicals for preparing recycled polyethylene.

[0022] [Figure 6] It shows this process for establishing the circular economy of waste plastics, in which the plastic / bio - oil blend is passed through the FCC feed pretreatment unit before the refinery FCC unit.

[0023] [Figure 7] It shows in a graph the thermogravimetric analysis (TGA) of the thermal stability of polyethylene and polypropylene.

DETAILED DESCRIPTION OF THE INVENTION

[0024] This process provides a method for recycling waste plastics such as polyethylene and / or polypropylene into valuable chemicals and fuels, and virgin polyethylene. Most of the polyethylene and polypropylene polymers are used in disposable plastics and discarded after use. This disposable plastic waste has become an increasingly important environmental problem. At present, there seem to be few options for recycling waste polyethylene and polypropylene into valuable chemicals and fuel products. Currently, only a small amount of polyethylene / polypropylene is recycled via chemical recycling, and these recycled and purified polymer pellets are pyrolyzed in a pyrolysis unit to produce fuels (naphtha, diesel), steam cracker feedstock, or slack wax.

[0025] Ethylene is the most widely produced building block of petrochemicals. Hundreds of millions of tons of ethylene are produced annually through steam cracking. Steam crackers use either gaseous feedstocks (ethane, propane, and / or butane) or liquid feedstocks (naphtha or diesel fuel). Steam cracking is a non-catalytic decomposition process carried out at extremely high temperatures, up to 850°C.

[0026] Polyethylene is widely used in a variety of consumer and industrial products. It is the most common plastic, with over 100 million tons of polyethylene resin produced annually. Its primary use is in packaging (plastic bags, plastic films, geomembranes, bottles, and other containers). Polyethylene is produced in three main forms, all sharing the same chemical formula (C2H4). n However, their molecular structures are different: high-density polyethylene (HDPE, approximately 0.940-0.965 g / m²) -3 ), linear low-density polyethylene (LLDPE, approximately 0.915~0.940 g / cm³) -3 ), low-density polyethylene (LDPE, <0.930 g / cm³) -3 HDPE has a low degree of branching and short side chains, while LDPE has a very high degree of branching and long side chains. LLDPE is a substantially linear polymer with a considerable number of short branches and is usually produced by copolymerization of ethylene and short-chain alpha-olefins.

[0027] Low-density polyethylene (LDPE) is produced by radical polymerization at very high pressures of 1,000 to 3,000 atmospheres and 150 to 300°C. This process uses small amounts of oxygen and / or organic peroxide initiators to produce a highly branched polymer with approximately 4,000 to 40,000 carbon atoms per average polymer molecule. High-density polyethylene (HDPE) is produced at relatively low pressures (10 to 80 atmospheres) and temperatures of 80 to 150°C in the presence of a catalyst. Ziegler-Natta organometallic catalysts (titanium(III) chloride with aluminum alkyl) and Phillips-type catalysts (chromium(IV) oxide supported on silica) are typically used, and this production is carried out via a slurry process using a loop reactor or a gas-phase process using a fluidized bed reactor. Hydrogen is mixed with ethylene to control the polymer chain length. The production conditions for linear low-density polyethylene (LLDPE) are the same as those for HDPE, except for the copolymerization of ethylene with short-chain alpha-olefins (1-butene or 1-hexene).

[0028] Today, due to the inefficiencies and ineffectiveness of the aforementioned recycling efforts, only a small fraction of used polyethylene products are collected for recycling.

[0029] A recycling process is currently available that converts plastic waste back into clean monomers, in which waste plastics and bio-based raw materials are simultaneously converted in a conversion unit. The clean monomers can then be used as polymerization monomers for value-added chemicals, fuels, etc. (e.g., polyethylene recycling). The process involves preparing a novel blend of waste plastics and bio-based raw materials. This blend is converted in a conversion unit, such as a catalytic process unit. The integrated process generates raw materials for producing clean monomers for polymerization. The integrated process produces streams of clean, recycled propane, propylene, butane, and naphtha, which become raw materials for an ethylene steam cracker and ultimately for polyethylene production. Recycling plastic waste does not degrade the quality of the final polyethylene product.

[0030] In parallel, high-quality gasoline, jet, and diesel fuels can be produced from waste plastics in a refinery. The fuel components are upgraded in appropriate refining units through a chemical conversion process. The final transport fuel produced by the integrated process is of high quality and meets fuel quality requirements.

[0031] Figure 1 shows a simplified process diagram of a basic case of a waste plastic pyrolysis process commonly used in the industry today. Generally, waste plastics are sorted together (1). The washed waste plastics 2 are converted into off-gas 4 and pyrolysis oil (liquid products) in a pyrolysis unit 3. The off-gas 4 from the pyrolysis unit is used as fuel to operate the pyrolysis unit. An on-site distillation unit separates the pyrolysis oil to produce naphtha and diesel 5 products, which are sold to the fuel market. The heavy pyrolysis oil fraction 6 is recycled back to the pyrolysis unit 3 to maximize fuel yield. Char 7 is removed from the pyrolysis unit 3. The heavy fraction 6 is rich in long-chain linear hydrocarbons and is very waxy (i.e., it produces paraffinic wax when cooled to ambient temperature). The wax can be separated from the heavy fraction 6 and sold to the wax market.

[0032] The waste plastic / bioresource blend of the present invention offers many advantages compared to the pyrolysis process. In this process, the waste plastic is not pyrolyzed. Rather, the blend of bioresource and waste plastic is directly converted in the conversion unit.

[0033] The blend is prepared in a high-temperature blending unit operating at a temperature exceeding the melting point of plastic (approximately 120-300°C), enabling the creation of a high-temperature, homogeneous liquid blend of plastic and bio-oil. This high-temperature, homogeneous liquid blend of plastic and bio-raw materials can be directly supplied to the conversion unit.

[0034] The preferred range for plastic in the composition blend is about 1 to 20 wt%. In one embodiment, conditions for preparing a high-temperature liquid blend include heating the blend to a temperature above the melting point of the plastic while vigorously mixing it with the bio-based raw materials. Process conditions include heating to 250 to 550°F, a residence time of 5 to 240 minutes at the final heating temperature, and atmospheric pressure of 0 to 10 psig. This can be carried out in open air, preferably in an oxygen-free atmosphere.

[0035] Alternatively, the blend is prepared in a stable blend preparation unit, and the homogeneous liquid blend at high temperature is cooled to ambient temperature in a controlled manner for easy storage and transport. Using this method, the stable blend can be prepared at a remote facility away from the refinery and transported to the refinery unit. The stable blend is then heated to a temperature above the melting point of the plastic and supplied to the refinery conversion unit. The stable blend is a physical mixture of micron-sized plastic particles finely suspended in petroleum-based oil. This mixture is stable, and the plastic particles do not settle or aggregate even during long-term storage.

[0036] The stable blend of the present invention is produced by a two-step process. In the first step, a high-temperature, homogeneous liquid blend of the plastic molten material and the bio-based material is produced. The preferred range of plastic composition in the blend is about 1 to 20 wt%. In one embodiment, conditions for preparing the high-temperature liquid blend include heating the plastic to a temperature above the melting point of the plastic while vigorously mixing it with the bio-based material. Preferred process conditions include heating to 250 to 550°F, a residence time of 5 to 240 minutes at the final heating temperature, and atmospheric pressure of 0 to 10 psig. This can be carried out in open air, preferably in an oxygen-free inert atmosphere.

[0037] In the second step, the high-temperature blend is cooled to a temperature below the melting point of the plastic while being continuously and vigorously mixed with the bio-based raw materials, and then further cooled to a lower temperature, preferably ambient temperature, to produce a stable blend.

[0038] The resulting composition contains a stable blend of waste plastic and bio-based raw materials, and is intended for direct conversion of waste plastic in conversion units such as refining process units. The resulting composition is novel and offers many advantages.

[0039] The stable blend is made from bio-based raw materials and 1-20 wt% plastic waste, where the plastic is mainly polyethylene, polypropylene, and / or polystyrene, and the plastic is in the form of finely dispersed micron-sized particles.

[0040] The significance of heating a blend to a temperature above the melting point of a single plastic becomes clear when using a single plastic. However, if the waste plastic is composed of multiple plastics, the temperature will exceed the melting point of the plastic with the highest melting point. Therefore, the temperature must exceed the melting point of all the plastics. Similarly, if the blend is cooled to a temperature below the melting point of the plastics, that temperature must be below the melting point of all the plastics that make up the blend.

[0041] Implementing these concepts offers several advantages compared to thermal decomposition.

[0042] The stable blend of plastics and bio-based materials can be stored for extended periods at ambient temperature and atmospheric pressure. No polymer aggregation or chemical / physical degradation of the blend is observed during storage. This facilitates the handling of waste plastic materials during storage or transportation.

[0043] Stable blends can be easily handled using standard pumps typically used in refineries or warehouses, or by using pumps equipped with transport tanks. Depending on the blend, it may be necessary to heat the blend to a temperature above its pour point in order to transfer it using a pump or to supply it to a conversion unit within the refinery. No polymer aggregation is observed during heating.

[0044] To supply to the conversion unit, the stable blend is further heated to a temperature above the melting point of the plastic, producing a homogeneous liquid blend of bio-based raw materials and plastic. This high-temperature, homogeneous liquid blend is then supplied directly to the petroleum refining process unit to convert waste plastic and bio-based raw materials into high-value, sustainable products with high yield.

[0045] Furthermore, compared to pyrolysis units, these blend preparation units operate at much lower temperatures (approximately 500°C to 600°C vs. 120°C to 300°C). Therefore, this process is far more energy-efficient than pyrolysis processes for preparing refined raw materials derived from waste plastics.

[0046] The use of the waste plastic / bioresource blend of the present invention further increases the overall yield of hydrocarbons obtained from waste plastics. This increase in yield is significant. The hydrocarbon yield using this blend can reach up to 98%. In contrast, pyrolysis produces a considerable amount of light products, about 10-30 wt%, and about 5-10 wt% char from plastic waste. These light hydrocarbons are used as fuel to operate the pyrolysis plant, as described above. Therefore, the liquid hydrocarbon yield from the pyrolysis plant is up to 70-80%.

[0047] Furthermore, when this blend is passed through a refining unit such as an FCC unit, only small amounts of off-gas are produced. The refining unit uses a (catalytic) catalytic cracking process, which is different from the pyrolysis process used in pyrolysis. Using a catalytic process minimizes the production of undesirable light by-products such as methane and ethane. Efficient product fractionation is performed in the refining unit, and all hydrocarbon product streams can be efficiently utilized to produce high-value materials. In the refinery co-supply, only about 2% of off-gas (H2, methane, ethane, ethylene) is produced. The C3 and C4 streams are captured to produce useful products such as cyclic polymers and / or high-quality fuel products. Therefore, the use of the petroleum / plastic blend of the present invention not only leads to an increase in hydrocarbons from waste plastics, but also results in a more energy-efficient recycling process compared to heat treatment processes such as pyrolysis.

[0048] This process converts large quantities of single-use waste plastics by blending them with bio-based raw material streams and integrating them into an oil refinery operation. The resulting process produces polymer raw materials (naphtha or C3 and C4, for ethylene crackers), as well as high-quality gasoline, jet fuel and diesel, and / or high-quality base oils.

[0049] Generally, this process provides a circular economy for polyethylene plants. Polyethylene is produced through the polymerization of pure ethylene. Clean ethylene can be produced using a steam cracker. A flow of naphtha or either C3 or C4 can be supplied to the steam cracker. The ethylene is then polymerized to produce polyethylene.

[0050] By adding refining operations to upgrade waste plastics into high-value products (gasoline, jet fuel, and diesel, base oils) and to produce clean ethylene for the production of ultimate polyethylene polymers, positive economic benefits are realized throughout the entire process, from recycled plastics to polyethylene products with the same quality as unused polymers. Furthermore, integrating this recycling process with petroleum refining operations achieves a more energy-efficient and effective process while avoiding the problems associated with refining operations.

[0051] The integration of refining operations is also crucial in another respect. Waste plastics contain contaminants such as calcium, magnesium, chlorides, nitrogen, sulfur, dienes, and heavy components, and these products cannot be used in large quantities for blending transport fuels. It has been found that by passing these products through refining units, contaminants can be captured in pre-treatment units, mitigating their adverse effects. Fuel components can be further upgraded in appropriate refining units using chemical conversion processes, and the final transport fuel produced by the integrated process can be of higher quality and meet fuel quality requirements. The integrated process produces a much cleaner and purer ethylene stream for polyethylene production. Mass production of these specifications makes a "circular economy" for recycled plastics possible.

[0052] The carbon entering and leaving the refining process is "transparent," meaning that not all molecules from waste plastics will necessarily recirculate back to the polyolefin plant and become the exact olefin product. Nevertheless, the net "green" carbon entering and leaving the refinery is positive and therefore considered "credit." These integrated processes will significantly reduce the amount of unused raw material required for polyethylene plants.

[0053] Figure 2 shows a method for preparing a high-temperature homogeneous blend of plastic and bio-based materials according to this process. This high-temperature liquid blend can be used for direct injection into a conversion unit. The preferred range for the plastic composition in the blend is about 1 to 20 wt%. When high molecular weight polypropylene (average molecular weight 250,000 or more) or high-density polyethylene (density greater than 0.93 g / cc) is mainly used as waste plastic, for example, at least 50 wt%, the amount of waste plastic used in the blend is more preferably about 10 wt%. This is because it increases the pour point and viscosity of the blend.

[0054] Preferred conditions for preparing the blend include heating the plastic to a temperature above the melting point of the plastic while vigorously mixing it with the bio-based raw materials. Preferred process conditions include heating to a temperature of 250–550°F, a residence time of 5–240 minutes at the final heating temperature, and atmospheric pressure of 0–10 psig. This can be carried out in open air, preferably in an oxygen-free inert atmosphere.

[0055] Referring to Figure 2 of the drawings, a stepwise preparation process for preparing a blend of plastic and bio-based raw materials is shown. The mixed waste plastics are sorted to produce post-use waste plastics 21 containing polyethylene and / or polypropylene. The waste plastics are cleaned (22) and then mixed with bio-based raw material oil 24 in a high-temperature blend preparation unit 23. After mixing in 23, a high-temperature homogeneous blend of plastic and bio-oil is recovered (25). Optionally, a filtration device (not shown) can be added to remove undissolved plastic particles or solid impurities present in the liquid blend. The blend of plastic and bio-oil can then be passed through a catalytic conversion unit 27. In one embodiment of this process, the conversion unit is a refining unit such as an FCC unit. Optionally, the conversion unit can co-process vacuum diesel 20 or conventional raw materials from other refineries.

[0056] Figure 3 shows a method for preparing a stable blend of plastic and oil for use in this process. The stable blend is produced by a two-step process in a stable blend preparation unit. In the first step, a high-temperature, homogeneous liquid blend of the plastic melt and bio-based raw materials is produced. This step is the same as the high-temperature blend preparation described in Figure 2. The preferred range for the plastic composition in the blend is about 1 to 20 wt%. When high molecular weight polypropylene (average molecular weight 250,000 or more) or high-density polyethylene (density greater than 0.93 g / cc) is mainly used as waste plastic, for example, at least 50 wt% of which is waste plastic, the amount of waste plastic used in the blend is more preferably about 10 wt%. This is because it increases the pour point and viscosity of the blend.

[0057] Preferred conditions for preparing a high-temperature homogeneous liquid blend include heating the plastic to a temperature above the melting point of the plastic while vigorously mixing it with the bio-based raw materials. Preferred process conditions include heating to a temperature of 250–550°F, a residence time of 5–240 minutes at the final heating temperature, and atmospheric pressure of 0–10 psig. This can be carried out in open air, preferably in an oxygen-free inert atmosphere.

[0058] In the second step, the high-temperature blend is cooled to a temperature below the melting point of the plastic while being continuously and vigorously mixed. Any diluent can be added during mixing. Further cooling to a lower temperature, preferably to ambient temperature, is performed to produce a stable blend of plastic and oil.

[0059] A stable blend is known to be a close physical mixture of plastic and bio-based materials. The plastic is in a "de-aggregated" state. The plastic maintains a fine dispersion of solid particles in the bio-based materials at temperatures below the melting point of the plastic, especially at ambient temperature. The blend is stable and easy to store and transport. In a refinery, the stable blend can be heated in a preheater to a temperature above the melting point of the plastic to produce a high-temperature, homogeneous liquid blend of plastic and bio-based materials. This high-temperature liquid blend can then be supplied to the refinery unit alone or as a co-feed with conventional refinery materials.

[0060] Figure 3 shows further details of the preparation of a stable blend. The stable blend is produced in a stable blend preparation unit 100 by a two-step process. As illustrated, clean waste 22 is passed through a high-temperature blend preparation unit 23. The selected plastic waste 22 is mixed with bio-based raw material oil 24 and heated in unit 23 to a temperature above the melting point of the plastic. Mixing is often carried out very vigorously. Mixing and heating conditions can generally be heating at temperatures in the range of about 250–550°F with a residence time of 5–240 minutes at the final heating temperature. Heating and mixing can be carried out in open air or in an oxygen-free inert atmosphere. The result is a high-temperature homogeneous liquid blend 101 of plastic and oil. Optionally, a filtration device (not shown) can be added to remove undissolved plastic particles or solid impurities present in the high-temperature homogeneous blend.

[0061] Next, the high-temperature blend 101 is cooled in unit 102 to a temperature below the melting point of the plastic while continuing to mix the blend of plastic and bio-based raw materials. During mixing and cooling, an optional diluent 103 may be added. Cooling is usually continued to ambient temperature to produce a stable blend of plastic and oil 29. In the refinery, the stable blend can be supplied to a preheater 130, which heats the blend to a temperature above the melting point of the plastic to produce a high-temperature, homogeneous mixture of plastic / oil blend 105, which is then supplied to the refining conversion unit 27. Optionally, the conversion unit can co-process vacuum diesel or other conventional refining raw materials.

[0062] The preferred plastic starting material for this process is sorted waste plastic, mainly containing polyethylene and polypropylene (plastic recycling classification types 2, 4, and 5). The pre-sorted waste plastic is washed, shredded or pelletized, and fed to the blending unit. Figure 4 shows the classification of plastic types for waste plastic recycling. Classification types 2, 4, and 5 are high-density polyethylene, low-density polyethylene, and polypropylene, respectively. Polyethylene and polypropylene waste plastics can be used in any combination. In this process, it is preferable to use at least some polyethylene waste plastic. Polystyrene (classification 6) can also be present in limited amounts.

[0063] Proper sorting of waste plastics is crucial to minimize contaminants such as N, Cl, and S. Plastic waste containing polyethylene terephthalate (plastic recycling classification type 1), polyvinyl chloride (plastic recycling classification type 3), and other polymers (plastic recycling classification type 7) needs to be sorted to less than 5%, preferably less than 1%, and most preferably less than 0.1%. This process can tolerate a moderate amount of polystyrene (plastic recycling classification type 6). Waste polystyrene needs to be sorted to less than 20%, preferably less than 10%, and most preferably less than 5%.

[0064] Washing waste plastics can remove metallic contaminants such as sodium, calcium, magnesium, and aluminum, as well as non-metallic contaminants from other waste sources. Non-metallic contaminants include contaminants from Group IV of the periodic table, such as silica; contaminants from Group V, such as phosphorus and nitrogen compounds; contaminants from Group VI, such as sulfur and oxygen compounds; and halogenated contaminants from Group VII, such as fluorides, chlorides, and iodides. Residual metals, non-metallic contaminants, and halides should be removed to less than 50 ppm, preferably less than 30 ppm, and most preferably less than 5 ppm.

[0065] The term "bio" refers to biochemical and / or natural chemical substances that exist in nature. Therefore, bio feedstock or bio oil will contain such natural chemical substances. Preferred starting bio feedstocks for blend preparation include triglycerides and fatty acids, plant-derived oils (such as palm oil, canola oil, corn oil, and soybean oil), and animal-derived fats and oils (such as animal fat, lard, schmalz (e.g., chicken fat), and fish oil), as well as mixtures thereof. In one embodiment, the bio feedstock may include biomass pyrolysis oil prepared by pyrolysis of bio feedstock material.

[0066] The most preferred bio-based raw materials are palm oil and tallow, which have high saturation and an iodine number of 91 or less (i.e., low unsaturation). The iodine number (or iodine value) is a measure of the unsaturation of fats, oils, and waxes. It is determined by measuring the mass (in grams) of iodine consumed by 100g of the substance. A higher number indicates a higher degree of unsaturation of the substance. This is similar to using the bromine number to measure the unsaturation of petroleum samples.

[0067] It has been found that biomaterials containing high iodine-value polyunsaturated fatty acids, such as soybean oil (iodine value 130), do not form a stable blend with plastics. However, a mixture of biomaterials consisting of biomaterials with a low iodine value (≤70) and biomaterials with high iodation (>70) can form a stable blend with plastics. It has been found that a mixture of biomaterials with an iodine value of approximately 95 or less forms a stable blend with plastics. In one embodiment, the mixture of biomaterials has an iodine value of 91 or less.

[0068] Furthermore, blends of plastics and bio-based raw materials can be blended with other diluting hydrocarbons, such as heptane, as needed to alter the properties of the blend, such as viscosity or pour point, making it easier to handle or process. Preferred blend hydrocarbon raw materials include standard petroleum-based raw materials such as vacuum gasoline (VGO), aromatic solvents, or light cycle oil (LCO). In one embodiment, the blend hydrocarbon raw materials include atmospheric gasoline, VGO, or heavy components recovered from other refining operations. In another embodiment, the blend hydrocarbon raw materials include LCO, heavy cycle oil (HCO), FCC naphtha, gasoline, diesel, toluene, or petroleum-derived aromatic solvents. To reduce viscosity, a portion of the liquid FCC product (e.g., naphtha and LCO) can also be recycled into the blend. In one embodiment, no petroleum raw materials are used, and only bio-based raw materials are used for the preparation of the blend and mixing with the blend.

[0069] While we do not wish to be bound by theory, the prepared stable blend is a close physical mixture of plastic and biomaterial for catalytic conversion units. This process produces a stable blend of biomaterial and plastic, in a "de-aggregated" state. This blend is stable and easy to store and transport. At the refinery, the stable blend is preheated to a temperature above the melting point of the plastic to produce a high-temperature, homogeneous liquid blend of plastic and biomaterial, which is then supplied to the conversion unit. Subsequently, both the biomaterial and plastic are simultaneously converted in the conversion unit using a typical refining catalyst containing zeolite and other active ingredients such as silica-alumina, alumina, and clay.

[0070] Catalytic conversion units, such as fluid catalytic cracking (FCC) units, hydrocracking units, and hydrotreatment units, convert a homogeneous liquid blend of plastics and biomaterials at high temperatures using the simultaneous conversion of plastics and biomaterials in the presence of a catalyst. The presence of a catalyst in the conversion unit makes it possible to convert waste plastics into high-value products at operating temperatures lower than typical thermal decomposition temperatures. In hydrotreatment units (hydrocracking units and hydrotreatment units), hydrogen is added to the unit to improve the conversion of plastics.

[0071] Fluid catalytic cracking is a preferred mode of catalytic conversion of stable blends. Catalyst selection is optimized to maximize monomer production for the manufacture of unused plastics.

[0072] The yield of undesirable by-products (off-gas, tar, coke) is lower than in typical pyrolysis processes. This blend may produce additional synergistic effects resulting from the interaction between plastic and bio-based raw materials during the conversion process.

[0073] Blending plastics with bio-based materials enables more efficient recycling of waste plastics, allowing for truly circular and sustainable production of plastics and chemicals. This is far more energy-efficient than current pyrolysis processes and enables recycling with a lower carbon footprint. The improved process will enable the establishment of a much larger circular economy by efficiently converting waste plastics into unused, high-quality ethylene polymers or value-added chemicals and fuels.

[0074] Alternatively, a blend of plastics and bio-based materials can be supplied to a petroleum refining and conversion unit for co-processing with petroleum-based oils. Refining and conversion units such as fluid catalytic cracking (FCC) units, hydrocracking units, and hydrotreatment units are preferred for the simultaneous conversion of plastics, bio-based materials, and petroleum-based oils.

[0075] In such cases, the refinery generally has its own supply of hydrocarbons that flow through the refining unit. For example, the hydrocarbon source can be VGO. The volume of the blend flow into the refining unit, such as an FCC unit, can constitute any practical or tolerable volume % (vol%) of the total flow to the refining unit. Generally, for practical reasons, the blend flow rate can be up to about 50 vol% of the total flow rate (i.e., refining flow rate and blend flow rate). In one embodiment, the blend flow rate is up to about 100 vol% of the total flow rate. The volume % (vol%) of the blend also depends on the final desired product. For chemicals centered on aromatic compounds and xylene, the blend flow rate % (flow%) can be much higher, if not 100%. In another embodiment, the volume flow rate of the blend is up to about 25 vol% of the total flow rate. About 50 vol% has been found to be a very practical amount in terms of impact on the refinery, while also providing excellent results and being tolerable. It is important to avoid adverse effects on the refinery and its products. If the amount of plastic in the final blend (including the plastic / oil blend and co-feed petroleum) exceeds 20 wt% of the final blend, problems may occur in the operation of the FCC unit. The final blend refers to the plastic / oil blend and any co-feed petroleum. The plastic / oil blend can account for up to 100% of the supply to the refining unit by volume.

[0076] In Figure 5, the cracking of the high-temperature blend of plastic / bio-oil 25 can be passed through 26 to the conversion FCC unit 27, either alone or in combination with co-supplied petroleum feedstocks (co-supplied petroleum products). The numbers in Figure 5 are the same as in Figures 2 and 3, and refer to the same streams or units. The FCC unit 27 produces liquefied petroleum gas (LPG) from the C3 and C4 olefin / paraffin streams 31 and 32, as well as naphtha 33 and heavy fractions 30. The C3 olefin / paraffin mixture stream 31, a mixture of propane and propylene, can be sent through 38 to the steam cracker 36 to produce ethylene 37. The ethylene 37 is fed to the ethylene polymerization unit 40 to produce polyethylene, and ultimately to produce polyethylene products 41.

[0077] The C4 stream 32 and at least some of the naphtha 33 can also be sent to the steam cracker 36 via 39 to produce ethylene 37. The ethylene is fed to the ethylene polymerization unit 40 to produce polyethylene, ultimately producing polyethylene product 41. Other hydrocarbon product streams from the FCC unit 27 (such as heavy fraction 30) are sent to a suitable refining unit 34 to be upgraded to clean gasoline, diesel, or jet fuel. The naphtha / gasoline 33 from the FCC unit may be passed directly to the gasoline pool 35, or may be further upgraded before being sent to the gasoline pool (not shown).

[0078] Figure 6 illustrates the integrated process of the present invention as shown in Figure 5, where the blend and the cofeed of the hydrocarbon purification flow 26 are first sent to the fluid catalytic cracking (FCC) feed pretreatment unit 77. In Figure 6, the same numbers as in Figure 5 refer to the same stream or purification unit.

[0079] FCC feed pretreatment units typically use a bimetallic (NiMo or CoMo) alumina catalyst in a fixed-bed reactor, hydrogenating the feed using an H2 gas flow at a reactor temperature of 660-780°F and a pressure of 1,000-2,000 psi. Purified FCC feed pretreatment units are effective in removing sulfur, nitrogen, phosphorus, silica, dienes, and metals that impair the catalytic performance of the FCC unit. Furthermore, this unit hydrogenates aromatics, improving the liquid yield of the FCC unit.

[0080] The pre-treated hydrocarbons from the feed pre-treatment unit 77 can be distilled to produce LPG, naphtha, and heavy fractions. The heavy fractions are sent to the FCC unit 27 to further produce C3, C4, FCC gasoline, and heavy fractions (labeled 31, 32, 33, and 30 respectively). The C4 stream and naphtha from the feed pre-treatment unit can be passed through other upgrade processes within the refinery. The C3 stream 31 can be passed through the steam cracker 36 to produce ethylene 37.

[0081] Steam crackers and ethylene polymerization units are preferably located near the refinery so that the raw materials (propane, butane, naphtha, or propane / propylene mixtures) can be transported via pipeline. In the case of petrochemical plants located far from the refinery, the raw materials can be delivered by truck, barge, railcar, or pipeline.

[0082] The benefits of a circular economy and effective and efficient recycling campaigns will be realized through this integrated process.

[0083] The following examples are provided as illustrations of the blends and processes of the present invention and are not intended to limit them. [Examples]

[0084] [Example 1] Characteristics of plastic samples and bio-based raw materials used for blend preparation Five plastic samples were purchased (low-density polyethylene (LDPE, Plastic A), high-density polyethylene (HDPE, Plastic B), two polypropylene samples with average molecular weights of approximately 12,000 (PP, Plastic C) and approximately 250,000 (PP, Plastic D), and polystyrene (PS, Plastic E)), and their properties were summarized in Table 1. [Table 1]

[0085] The bio-based raw materials used to prepare the blend with the plastic melt included palm oil, animal fat, and soybean oil, whose properties are shown in Table 2. [Table 2]

[0086] Thermogravimetric analysis (TGA) was performed on plastic A (LDPE) and plastic C (polypropylene) to confirm that the plastic materials were thermally stable at temperatures sufficiently higher than the molten material preparation temperature. The TGA results shown in Figure 7 indicate that the LDPE sample was stable up to 800°F and the polypropylene sample was stable up to 700°F.

[0087] [Example 2] Preparation of a stable blend of palm oil and plastic Several blends of palm oil and plastic were prepared by adding plastic pellets (plastics A-D) to palm oil (bioresource #1).

[0088] The following procedure was used: Palm oil (waxy solid) was placed in a beaker at ambient temperature. The palm oil was heated on a heating mantle while being stirred with a magnetic stirrer. The temperature of the palm oil was gradually increased from 270°F to 400°F, and then pre-weighed plastic pellets (solid) were slowly added to the hot palm oil while stirring and heating continued. After the plastic pellets had dissolved, the stirred solution was held at the final temperature for an additional 30 minutes for the LDPE blend and the Plastic C polypropylene blend, and for 60 minutes for the HDPE blend and the Plastic D polypropylene blend. The blend was then cooled to ambient temperature while stirring. Visual observation showed that the mixture was completely homogeneous. After cooling to ambient temperature, the plastic and palm oil blends exhibited the appearance of a waxy solid palm oil, but the curing temperature (or solidification temperature) was different from that of the palm oil at the start of the procedure.

[0089] To assess the handling requirements of the materials, the pour point (according to ASTM D5950-14) and viscosity (according to ASTM D445) of the blends were measured. Furthermore, the content of high-temperature heptane-insoluble substances was measured according to the procedure of ASTM D3279. The high-temperature heptane-insoluble method measures the weight percentage of substances in the oil that are insoluble in high-temperature heptane at 80°C. This method uses a 0.8-micron membrane filter to separate the insoluble substances. The heptane-insoluble content provides information about undissolved plastics in the blend.

[0090] The stability of the materials was observed by visual inspection. The blend of plastic and palm oil was stable, and no changes were observed during the 3-month observation period.

[0091] Table 3 below lists the prepared samples and summarizes their characteristics. [Table 3]

[0092] Pour point and viscosity values ​​are used as guidelines for equipment selection and operating procedures. Blends prepared with added plastics exhibit a moderate increase in pour point and viscosity compared to pure bio-based cases. These changes can be accommodated with minimal or no modifications in typical purification equipment. Blend tanks are heated to a temperature above the pour point to transform the physical state of the blend into an easily transferable liquid. The liquid blend can then be transferred to transport containers or purification units via pumping, gravity discharge, or pressure difference transfer.

[0093] The stable blend remains a physical mixture at temperatures up to 80°C. Plastics were separated from the blend using a high-temperature heptane insolubility test. At 80°C, all the wax in the palm oil dissolved in the heptane solvent (Example 2-1), and the heptane-insoluble solids amounted to only 0.02 wt%. The weight percentage of heptane-insoluble material originates from undissolved plastic filtered through a 0.8 micron membrane filter. The amounts recovered as solid material in Examples 2-2 and 2-4 indicate that the heptane-insoluble solids were 7.6 wt% and 7.8 wt%, respectively, which is approximately the same amount of plastic added for blend preparation. The recovered amounts are 2.2 wt% to 2.4 wt% less, suggesting that the blend may contain very fine particles of submicron size. The heptane insolubility results in Table 3 clearly demonstrate that plastics are a physical mixture of solid particles dispersed in palm oil in the blend at 80°C, and that the majority of the plastic particles can be separated by a 0.8 micron filter.

[0094] [Example 3] Preparation of a stable blend of animal fat and plastic Several blends of animal fat and plastic samples were prepared by adding plastic pellets to the animal fat raw material (bio-raw material #2).

[0095] The procedure described in Example 2 was used to prepare these blends. [Table 4]

[0096] The blend prepared by adding plastic to animal fat showed a moderate increase in pour point and viscosity compared to the pure bio-based case, similar to the results for palm oil shown in Example 2.

[0097] The weight percentage of heptane-insoluble material recovered as solids closely matches the amount of plastic added to the blend preparations. The base case tallow (Example 3-1) contained only 0.04 wt% heptane-insoluble material, while the stable blends (Examples 3-2 and 3-4) contained 7.7 wt% and 8.6 wt% heptane-insoluble solids, respectively, which is approximately the same as the amount of plastic added for blend preparation. The recovered amounts were 1.4 wt% to 2.3 wt% less, suggesting that the blends may contain very fine particles of submicron size. The heptane-insoluble results in Table 4 clearly show that the plastic is a physical mixture of solid particles dispersed in palm oil in the blend at 80°C, and that the majority of the plastic particles can be separated by a 0.8 micron filter.

[0098] [Example 4] Preparation of a blend of soybean oil and plastic (comparative example) We attempted to prepare a blend of soybean oil (biofodine #3) and plastic using plastic pellets (plastics A-D) and the procedure described in Example 2. Surprisingly, the soybean oil and plastic did not form a homogeneous liquid melt at high temperatures when heated together, as was the case with palm oil and animal fat. When the mixture was heated above the melting point of the plastic, the pellets softened and lost their shape. However, instead of forming a homogeneous liquid as in other cases, the plastic melt formed a separate liquid phase from the soybean oil (SBO). Upon cooling, the plastic phase agglomerated, forming large solid pieces of plastic. A possible reason for this is that SBO has a much higher degree of unsaturation. This is evident from its lower H / C ratio compared to animal fat and palm oil, as well as from the measured iodine value. This also explains why most petroleum raw materials, and highly saturated oils and fats, which are determined by their iodine value, readily dissolve plastic. [Table 5]

[0099] [Example 5] Preparation of a blend of soybean oil, palm oil, and plastic A mixture of soybean oil and palm oil in a 1:1 weight ratio (mixed bio-raw material) was prepared. Using this mixed bio-raw material, a blend of palm oil, soybean oil, and plastic was successfully prepared by adding plastic pellets (plastics A and C) to a 1:1 mixture of palm oil and soybean oil (bio-raw material #1 and bio-raw material #3). Therefore, soybean oil can be used as a component of mixed bio-raw materials. The stable blend showed a good shelf life and did not change for several months. These results indicate that soybean oil can also be used as a bio-raw material to prepare a stable blend with plastic by reducing the degree of unsaturation when used with other bio-raw materials.

[0100] This test also indicates the acceptable iodine value for successfully producing stable blends of plastics and biomaterials. The iodine value of a 1:1 mixture of soybean oil and palm oil is estimated to be 91. These results indicate that soybean oil or other highly unsaturated oils can also be used as biomaterials for preparing stable blends with plastics, as long as the overall degree of unsaturation of the mixed biomaterials has an iodine value of 95 or less, preferably 91 or less. [Table 6]

[0101] [Example 6] Preparation of a blend of soybean oil, animal fat, and plastic A 1:1 mixture of soybean oil and animal fat was prepared. Using a mixed bio-raw material, a blend of animal fat, soybean oil, and plastic was successfully prepared by adding plastic pellets (plastics A and C) to a 1:1 mixture of animal fat and soybean oil (bio-raw material #2 and bio-raw material #3). The stable blend showed a good shelf life, with no changes observed for several months. These results again demonstrate that soybean oil can also be used as a bio-raw material to prepare a stable blend with plastic by reducing the degree of unsaturation when used with other bio-raw materials.

[0102] This test also indicates the acceptable iodine value for successfully producing a stable blend of plastics and bio-based materials. The iodine value of a 1:1 mixture of soybean oil and animal fat is estimated to be 88. [Table 7]

[0103] To investigate the effects of processing waste plastics and bio-based materials in an FCC unit, laboratory tests were conducted using a fluid catalytic cracking (FCC) process with stable blends of plastics and bio-based materials. Two FCC catalysts were used in these tests: one was a ZSM-5-containing FCC catalyst made from ZSM-5 zeolite (a 10-membered, medium-pore zeolite), and the other was a USY-containing FCC catalyst made from USY (a 12-membered, medium-pore zeolite). Three bio-based materials were used: palm oil, soybean oil, and animal fat.

[0104] Catalytic catalytic cracking experiments were conducted using an ACE (Advanced Cracking Evaluation) Model C unit manufactured by Kayser Technology Inc. (Texas, USA). The reactor used in the ACE unit was a fixed fluidized bed reactor with an inner diameter of 1.6 cm. Nitrogen was used as the fluidizing gas and was introduced from both the bottom and the top. The fluidizing gas from the top was used to carry the feed injected via a three-way valve from a calibrated syringe feed pump. The experiments were conducted at atmospheric pressure and a temperature of 975°F. In each experiment, a constant amount of feed of 1.5 grams was injected at a rate of 1.2 grams / min for 75 seconds. The catalyst / oil ratio was maintained at 6. After 75 seconds of feed injection, the catalyst was stripped with nitrogen for 525 seconds. During the catalytic catalytic cracking and stripping processes, the liquid product was collected in a sample vial attached to a glass receiver at the end of the reactor outlet and maintained at -15°C. The gaseous product was collected in a sealed stainless steel container (12.6 L) pre-filled with 1 atm of N2. Immediately after feed injection was complete, the gaseous product was mixed with an electric stirrer rotating at 60 rpm. After stripping, the gaseous product was mixed for a further 10 minutes to ensure homogeneity. The final gaseous product was analyzed using a refined gas analyzer (RGA). After the completion of the stripping process, catalytic regeneration was performed in situ in the presence of air at 1300°F. The regenerated exhaust gas passed through a catalytic converter packed with CuO pellets (LECO Inc.) to oxidize CO to CO2. The exhaust gas was then analyzed using an online IR analyzer installed downstream of the catalytic converter. The amount of coke deposited during the decomposition process was calculated from the CO2 concentration measured by the IR analyzer.

[0105] Gaseous products, mainly C1 to C7 hydrocarbons, were decomposed using a Regulatory Gas (RGA). The RGA is a customized Agilent 7890B GC equipped with three detectors: a flame ionization detector (FID) for hydrocarbons and two thermal conductivity detectors for nitrogen and hydrogen. The RGA was also fitted with a methanizer to quantify trace amounts of CO and CO2 in the gaseous products resulting from the decomposition of bio-based raw materials such as soybean oil, palm oil, or animal fat. The gaseous products were classified into dry gas (C2-hydrocarbons and hydrogen) and LPG (C3 and C4 hydrocarbons). CO and CO2 were excluded from the dry gas. Their yields were reported separately. Liquid products were quantified and analyzed using a simulated distillation GC (Agilent 6890) according to the ASTM D2887 method. The liquid products were separated into gasoline (C5~430°F), LCO (430°F~650°F), and HCO (650°F+). The gasoline (C5+ hydrocarbons) in the gaseous product was combined with the gasoline in the liquid product to form the total gasoline. The light components (C5+ hydrocarbons) in the liquid product 5- ) was also subtracted from the liquid product and added back to the C3 and C4 species using an empirical distribution. The mass balance was between 98% and 101% in most experiments.

[0106] Detailed hydrocarbon analysis (DHA) was also performed on the gasoline portion of the liquid product using an Agilent 6890A and Hydrocarbon Expert software from Separation Systems Inc. (Florida) to analyze PONA and octane (RON and MON). DHA analysis was not performed on the gasoline portion of the gaseous product. However, the DHA results still provided valuable information for evaluating the characteristics of the (catalytic) catalytic cracking products.

[0107] [Example 7] Direct conversion of plastics and palm oil via FCC (using ZSM-5 catalyst) Laboratory tests of the fluid catalytic cracking (FCC) process were conducted using stable blends of plastics and biomaterials (Examples 2-2 and 5-1) and an FCC catalyst made of ZSM-5 zeolite. The results are summarized in Table 8. [Table 8]

[0108] The results in Table 8 show that blends of waste plastics and bio-based raw materials (palm oil and soybean oil) are successfully converted with a ZSM-5-containing FCC catalyst. Surprisingly, the medium-pore 10-membered ring ZSM-5 catalyst can convert over 95 wt% of the plastic / biological raw material blend under typical FCC process conditions (Examples 7-1 to 7-3). Due to the high conversion rate, the yields of LCO and HCO are very low. In all of these cases, very high yields of LPG and aromatics are obtained, indicating that this process can be used to produce raw materials for polymer and chemical manufacturing without using petroleum resources.

[0109] Adding 10 wt% plastic to palm oil resulted in only slight changes in the performance of the FCC unit in terms of conversion rate and yields of dry gas and coke. This suggests that co-processing of waste plastics and bio-based materials is readily feasible (Examples 7-1 and 7-2). Blending 10 wt% low-density polyethylene (Plastic A) with palm oil resulted in only a slight increase in coke and dry gas yields, but a significant increase in LPG yield (35 wt% vs. 37 wt%) and total aromatic yield (76 wt% vs. 81 wt% in the gasoline fraction) was observed. The substantial increase in LPG and aromatic yields from the plastic-containing blend was entirely unexpected. This clearly demonstrates that the synergistic effect of bio-based materials and plastic blends increases LPG and aromatic yields.

[0110] Blending 10 wt% of plastic with palm oil and soybean oil (Example 7-3) also consistently yielded high levels of LPG and aromatic compounds.

[0111] These results indicate that the ZSM-5 catalyst, fabricated from medium-pore zeolite, is a preferred catalyst for the production of LPG olefins and aromatic compounds when converting biomaterials / plastic blends.

[0112] The high yield of LPG obtained through this process is significant. LPG and LPG olefins are preferred raw materials for the production of polyethylene and polypropylene.

[0113] The high yield of aromatics from this process is also very important, as these aromatics can be used in the production of polystyrene or polyethylene terephthalate. Another surprising discovery was the selectivity of paraxylene to total xylene. When using the ZSM-5 catalyst, the xylene produced in this process is substantially paraxylene, with a paraxylene selectivity of approximately 61-70% (as a percentage of the total xylene produced). Paraxylene is the most desirable xylene isomer for the production of polyethylene terephthalate polymers.

[0114] This process is more suitable for the manufacture of chemicals, but some of the products can be used in the production of premium gasoline fuel. The gasoline produced by this process has a high octane rating of over 100 due to the high aromatic content in the gasoline fraction. Due to the high conversion rate, the yields of LCO and HCO are low.

[0115] [Example 8] Direct conversion of plastics and palm oil via FCC (using USY catalyst) Laboratory tests of the fluid catalytic cracking (FCC) process were conducted using stable blends of plastic and palm oil (Examples 2-2 and 5-1) and a USY zeolite FCC catalyst. The results are summarized in Table 9. [Table 9]

[0116] The results in Table 9 show that blends of waste plastics and bio-based raw materials (palm oil and soybean oil) are successfully converted with a USY-containing FCC catalyst. The overall conversion rate of the blends is 86–87% under typical FCC process conditions (Examples 8-1 to 8-3). In all of these cases, low dry gas yields (undesirable products) and high LPG, gasoline, and LCO yields (desirable products) are obtained, demonstrating that this process can be used for the simultaneous production of raw materials for chemical manufacturing and premium renewable fuels without using petroleum resources.

[0117] Adding 10 wt% plastic to palm oil resulted in only slight changes to the performance of the FCC unit in terms of conversion rate and yield of dry gas and coke. This indicates that co-processing of waste plastics and bio-based materials is easily feasible (Examples 8-1 and 8-2). Blending 10 wt% low-density polyethylene (Plastic A) with palm oil had only slight effects on the product yields: LPG yield (19.5 wt% vs. 21.3 wt%), gasoline yield (45.4 wt% vs. 44.9 wt%), LCO (10.9 wt% vs. 10.0 wt%), and HCO yield (3.2 wt% vs. 3.3 wt%). However, it was observed that the paraffinic properties of the plastic reduced the gasoline octane rating by 3 points (from 91 to 88).

[0118] Blending 10 wt% of plastic with palm oil and soybean oil (Example 8-3) also consistently yielded high LPG and gasoline production.

[0119] When using the USY catalyst, no synergistic effect between the bio-based raw materials and plastics was observed, nor was the paraxylene selectivity observed with the ZSM-5 catalyst shown in Example 7-2. Compared to the ZSM-5 catalyst (Example 8-2 vs. Example 7-2), the USY catalyst showed a much higher LCO yield (10.0 wt% vs. 1.4 wt%) and a much higher HCO yield (3.3 wt% vs. 0.7 wt%). Furthermore, USY demonstrated much higher coke selectivity (6.7 wt% vs. 1.7 wt%) and lower off-gas yield (2.2 wt% vs. 6.5 wt%). These results indicate that the USY catalyst, fabricated with large-pore zeolite, is a preferred FCC catalyst for the simultaneous production of chemical raw materials and premium fuels.

[0120] Some of the products can be used in the manufacture of premium fuels. The gasoline produced in this process has an octane rating of 91-88. Due to the paraffin properties of plastic, the addition of polyethylene plastic slightly reduces the octane rating. Due to the flexibility of the refinery's blending, this reduction in octane rating can be compensated for by fine-tuning the blend.

[0121] The high yield of LPG obtained through this process is significant. LPG and LPG olefins are preferred raw materials for the production of polyethylene and polypropylene.

[0122] The high yield of aromatics obtained through this process is also important because these aromatics can be used in the production of polystyrene or polyethylene terephthalate.

[0123] [Example 9] Direct conversion of plastics and animal fats via FCC (using ZSM-5 catalyst) Laboratory tests of the fluid catalytic cracking (FCC) process were conducted using stable blends of plastics and biomaterials (Examples 3-2, 3-4, and 6-1) and an FCC catalyst made of ZSM-5 zeolite. The results are summarized in Table 10. [Table 10]

[0124] The results in Table 10 show that blends of waste plastics and bio-based raw materials (tallow and soybean oil) are successfully converted with the ZSM-5-containing FCC catalyst. Similar to co-processing with palm oil, the ZSM-5 catalyst showed very high conversion rates of over 95 wt% of the plastic / biological raw material blend under typical FCC process conditions (Examples 9-1 to 9-4). Due to the high conversion rates, the yields of LCO and HCO were very low. In all of these cases, very high yields of LPG and aromatics were obtained, indicating that this process can be used to produce raw materials for polymer and chemical manufacturing without using petroleum resources.

[0125] Adding 10 wt% polyethylene or polypropylene plastic to tallow resulted in only slight changes in the performance of the FCC unit in terms of conversion rate and yield of dry gas and coke. This suggests that co-processing of waste plastics and bio-based materials is readily feasible (Examples 9-1 vs. 9-2 and 9-3). Unlike the case of palm oil shown in Example 7-2, blending 10 wt% low-density polyethylene (plastic A) and polypropylene (plastic C) with tallow did not result in a synergistic effect on LPG yield and aromatic yield. LPG yield (36.5 wt% vs. 35.5-36.4 wt%) and total aromatic yield (80.6 wt% vs. 80.3-80.6 wt% in the gasoline fraction) were similar to those obtained with co-supplying of plastics.

[0126] Blending 10 wt% of plastic with animal fat and soybean oil (Example 9-4) also consistently yielded high LPG and aromatic compound production, as well as high paraxylene selectivity.

[0127] The high yields of LPG and aromatics shown in Table 10 again demonstrate that the ZSM-5 catalyst, made from medium-pore zeolite, is a preferred catalyst for the production of LPG olefins and aromatic compounds from blends of plastics and bio-based materials (such as animal fat). When using the ZSM-5 catalyst, the xylene produced in this process is substantially para-xylene, with a para-xylene selectivity of approximately 65-67% (as a percentage of the total xylene produced).

[0128] [Example 10] Direct conversion of plastics and animal fats via FCC (using USY catalyst) Laboratory tests of the fluid catalytic cracking (FCC) process were conducted using stable blends of plastic and animal fat bio-based materials (Examples 3-2, 3-4, and 6-1) and a USY zeolite FCC catalyst. The results are summarized in Table 11. [Table 11]

[0129] The results in Table 11 show that blends of waste plastics and bio-based raw materials (tallow and soybean oil) are successfully converted with a USY-containing FCC catalyst. The overall conversion rate of the blends is 85–87% under typical FCC process conditions (Examples 10-1 to 10-4). In all of these cases, low dry gas yields (undesirable products) and high LPG, gasoline, and LCO yields (desirable products) are obtained, demonstrating that this process can be used for the simultaneous production of raw materials for chemical manufacturing and premium fuels without using petroleum resources.

[0130] Adding 10 wt% of plastic to tallow resulted in only slight changes in the performance of the FCC unit in terms of conversion rate and yields of dry gas and coke. This indicates that co-processing of waste plastics and bio-based materials is readily feasible (Examples 10-1, 10-2, and 10-3). Blending 10 wt% of low-density polyethylene (plastic A) or polypropylene (plastic C) with tallow slightly increased the LPG yield (20.1 wt% vs. 21.6–22.6 wt%), but had only slight effects on the yields of other products: gasoline yield (44.6 wt% vs. 43.6–44.3 wt%), LCO (10.5 wt% vs. 10.2–11.0 wt%), and HCO yield (3.5 wt% vs. 3.2–3.3 wt%). No decrease in gasoline octane was observed with polyethylene co-supply, while a 2-point increase in gasoline octane was observed with polypropylene co-supply (88.0 vs. 87.9 vs. 92.3).

[0131] These results indicate that USY catalysts fabricated with large-pore zeolites are preferred catalysts for the simultaneous production of chemical feedstocks and premium renewable fuels.

[0132] Where used in this disclosure, the words “comprises” or “comprising” are intended as open-ended transitional terms meaning to include the indicated elements, but not necessarily to exclude other unindicated elements. The phrases “consists essentially of” or “consisting essentially of” are intended to mean to exclude other elements that are essentially important to the composition. The phrases “consisting of” or “consists of” are intended as transitional terms meaning to exclude everything other than the elements described, except for trace amounts of impurities.

[0133] All patents and publications referenced herein are incorporated herein by reference to the extent that they do not conflict with this specification. It will be understood that the specific structures, functions, and operations of the above embodiments are not necessary for carrying out the invention and are included in the description merely to complete the exemplary embodiments or a subset of embodiments. Furthermore, it will be understood that while specific structures, functions, and operations described in the above-referenced patents and publications can be carried out in combination with the invention, they are not essential for its implementation. Accordingly, it will be understood that the invention can be carried out as specifically described without actually departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A process for converting waste plastic into recycled materials for polyethylene polymerization, (a) A step of selecting waste plastics including polyethylene and / or polypropylene, (b) A step of preparing a blend of biomaterials and selected waste plastics, wherein the biomaterials comprise one or more selected from triglycerides, fatty acids, plant-derived oils, and animal-derived fats and / or oils, and the blend is prepared by mixing the selected waste plastics with the biomaterials at a temperature above the melting point of the waste plastics to obtain a liquid blend, wherein the blend comprises 20 wt% or less of the selected waste plastics, (c) The process of passing the blend through an FCC unit at a temperature exceeding the melting point of the waste plastics in the blend. (d) From the FCC unit, C ３ A process for recovering an olefin / paraffin mixture, (e) C ３ The process of passing an olefin / paraffin mixture through a steam cracker to produce ethylene, The above process, including.

2. The process according to claim 1, wherein gasoline and heavy fractions are recovered from an FCC unit.

3. The process according to claim 1, wherein the blend of (b) is prepared by mixing selected waste plastics with bio-based materials at a temperature in the range of 250°F to 550°F.

4. The process according to claim 1, wherein the blend in (b) is a blend of waste plastic and bio-based raw materials, wherein the waste plastic particles in the blend remain dispersed without settling or agglomerating during storage.

5. The process according to claim 1, wherein ethylene is polymerized to polyethylene.

6. The process according to claim 1, wherein the waste plastics selected in (a) include plastics from classification groups 2, 4, and / or 5.

7. The process according to claim 2, wherein gasoline recovered from an FCC unit is sent to a gasoline blend pool.

8. C ４ The process according to claim 1, wherein the flow and heavy fractions are recovered from the FCC unit distillation column and further processed in a refinery to obtain clean gasoline, diesel, or jet fuel.

9. The process according to claim 1, wherein the volumetric flow rate of the blend flowing to the FCC unit in (c) constitutes a maximum of approximately 100 vol% of the total hydrocarbon flow rate flowing to the FCC unit.

10. The process according to claim 1, wherein the volumetric flow rate of the blend flowing to the FCC unit in (c) constitutes approximately 50 vol% of the total hydrocarbon flow rate flowing to the FCC unit.

11. The process according to claim 10, wherein the blend flow rate constitutes a maximum of approximately 25 vol% of the total flow rate to the FCC unit.

12. The process according to claim 1, wherein the blend of the bio-material and the selected waste plastic in (b) is prepared by heating the mixture of the waste plastic and the bio-material to a temperature above the melting point of the plastic, and then cooling the blend to a temperature below the melting point of the waste plastic.

13. The process according to claim 1, wherein the bio-raw material comprises triglycerides and / or fatty acids.

14. The process according to claim 1, wherein the bio-raw material comprises plant-derived oils and / or animal-derived fats and oils.

15. The process according to claim 14, wherein the plant-derived oil comprises palm oil, canola oil, corn oil, soybean oil, or a mixture thereof.

16. The process according to claim 14, wherein the bio-raw material comprises animal fat, lard, schmaltz, fish oil, or a mixture thereof.

17. The process according to claim 1, wherein the bio-raw material comprises palm oil, animal fat, soybean oil, or a mixture thereof.

18. The process according to claim 1, wherein the bio-raw material includes biomass pyrolysis oil.

19. The process according to claim 1, wherein the bio-raw material includes a bio-raw material or mixed bio-raw material having an iodine value of 95 or less.

20. The process according to claim 19, wherein the iodine value is 91 or less.

21. The process according to claim 19, wherein the bio-raw material comprises a mixture of bio-oil or fat having an iodine value of 70 or less and bio-oil or fat having an iodine value exceeding 70.

22. The process according to claim 1, wherein a stream of petroleum raw materials containing LCO or gasoline is added to reduce the blend viscosity.

23. The process according to claim 1, wherein the blend passed through the FCC unit is mixed with petroleum raw materials.

24. The process according to claim 23, wherein petroleum raw materials constitute 1 to 50 vol% of the mixed blend.

25. The process according to claim 24, wherein the petroleum raw materials include atmospheric pressure diesel, vacuum gasoline (VGO), atmospheric pressure residue, petroleum-derived oil, petroleum-based materials, and / or heavy components recovered from refining operations.

26. The process according to claim 24, wherein the petroleum raw materials include light cycle oil (LCO), heavy cycle oil (HCO), FCC naphtha, gasoline, diesel, toluene, and / or petroleum-derived aromatic solvents.

27. The process according to claim 1, wherein the blend passed through the FCC unit is mixed with a recycled flow containing liquid products from the FCC unit, thereby reducing the viscosity of the blend.

28. The process according to claim 1, wherein ethylene is polymerized to produce polyethylene.

29. A method for producing polyethylene, comprising performing the process described in claim 28 on a blend of biomaterials and waste plastics.

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